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Sample records for reliable change indices

  1. Reliable change indices and standardized regression-based change score norms for evaluating neuropsychological change in children with epilepsy.

    Science.gov (United States)

    Busch, Robyn M; Lineweaver, Tara T; Ferguson, Lisa; Haut, Jennifer S

    2015-06-01

    Reliable change indices (RCIs) and standardized regression-based (SRB) change score norms permit evaluation of meaningful changes in test scores following treatment interventions, like epilepsy surgery, while accounting for test-retest reliability, practice effects, score fluctuations due to error, and relevant clinical and demographic factors. Although these methods are frequently used to assess cognitive change after epilepsy surgery in adults, they have not been widely applied to examine cognitive change in children with epilepsy. The goal of the current study was to develop RCIs and SRB change score norms for use in children with epilepsy. Sixty-three children with epilepsy (age range: 6-16; M=10.19, SD=2.58) underwent comprehensive neuropsychological evaluations at two time points an average of 12 months apart. Practice effect-adjusted RCIs and SRB change score norms were calculated for all cognitive measures in the battery. Practice effects were quite variable across the neuropsychological measures, with the greatest differences observed among older children, particularly on the Children's Memory Scale and Wisconsin Card Sorting Test. There was also notable variability in test-retest reliabilities across measures in the battery, with coefficients ranging from 0.14 to 0.92. Reliable change indices and SRB change score norms for use in assessing meaningful cognitive change in children following epilepsy surgery are provided for measures with reliability coefficients above 0.50. This is the first study to provide RCIs and SRB change score norms for a comprehensive neuropsychological battery based on a large sample of children with epilepsy. Tables to aid in evaluating cognitive changes in children who have undergone epilepsy surgery are provided for clinical use. An Excel sheet to perform all relevant calculations is also available to interested clinicians or researchers. Copyright © 2015 Elsevier Inc. All rights reserved.

  2. Robustness of reliable change indices to variability in Parkinson's disease with mild cognitive impairment.

    Science.gov (United States)

    Turner, T H; Renfroe, J B; Elm, J; Duppstadt-Delambo, A; Hinson, V K

    2016-01-01

    Ability to identify change is crucial for measuring response to interventions and tracking disease progression. Beyond psychometrics, investigations of Parkinson's disease with mild cognitive impairment (PD-MCI) must consider fluctuating medication, motor, and mental status. One solution is to employ 90% reliable change indices (RCIs) from test manuals to account for account measurement error and practice effects. The current study examined robustness of 90% RCIs for 19 commonly used executive function tests in 14 PD-MCI subjects assigned to the placebo arm of a 10-week randomized controlled trial of atomoxetine in PD-MCI. Using 90% RCIs, the typical participant showed spurious improvement on one measure, and spurious decline on another. Reliability estimates from healthy adults standardization samples and PD-MCI were similar. In contrast to healthy adult samples, practice effects were minimal in this PD-MCI group. Separate 90% RCIs based on the PD-MCI sample did not further reduce error rate. In the present study, application of 90% RCIs based on healthy adults in standardization samples effectively reduced misidentification of change in a sample of PD-MCI. Our findings support continued application of 90% RCIs when using executive function tests to assess change in neurological populations with fluctuating status.

  3. Reliable Change Indices and Standardized Regression-Based Change Score Norms for Evaluating Neuropsychological Change in Children with Epilepsy

    Science.gov (United States)

    Busch, Robyn M.; Lineweaver, Tara T.; Ferguson, Lisa; Haut, Jennifer S.

    2015-01-01

    Reliable change index scores (RCIs) and standardized regression-based change score norms (SRBs) permit evaluation of meaningful changes in test scores following treatment interventions, like epilepsy surgery, while accounting for test-retest reliability, practice effects, score fluctuations due to error, and relevant clinical and demographic factors. Although these methods are frequently used to assess cognitive change after epilepsy surgery in adults, they have not been widely applied to examine cognitive change in children with epilepsy. The goal of the current study was to develop RCIs and SRBs for use in children with epilepsy. Sixty-three children with epilepsy (age range 6–16; M=10.19, SD=2.58) underwent comprehensive neuropsychological evaluations at two time points an average of 12 months apart. Practice adjusted RCIs and SRBs were calculated for all cognitive measures in the battery. Practice effects were quite variable across the neuropsychological measures, with the greatest differences observed among older children, particularly on the Children’s Memory Scale and Wisconsin Card Sorting Test. There was also notable variability in test-retest reliabilities across measures in the battery, with coefficients ranging from 0.14 to 0.92. RCIs and SRBs for use in assessing meaningful cognitive change in children following epilepsy surgery are provided for measures with reliability coefficients above 0.50. This is the first study to provide RCIs and SRBs for a comprehensive neuropsychological battery based on a large sample of children with epilepsy. Tables to aid in evaluating cognitive changes in children who have undergone epilepsy surgery are provided for clinical use. An excel sheet to perform all relevant calculations is also available to interested clinicians or researchers. PMID:26043163

  4. The Reliability of EMU FIscal Indicators: Risks and Safeguards

    OpenAIRE

    Fabrizio Balassone; Daniele Franco; Stefania Zotteri

    2007-01-01

    The reliability of EMU�s fiscal indicators has been questioned by recent episodes of large upward deficit revisions. This paper discusses the causes of such revisions in order to identify ways to improve monitoring. The computation of EMU�s deficit indicator involves the assessment of accrued revenue and expenditure and the identification of transactions in financial assets. Both can open margins for opportunistic accounting. However, crosschecks between deficit and changes in gross nomin...

  5. Cognitive outcome and reliable change indices two years following bilateral subthalamic nucleus deep brain stimulation.

    Science.gov (United States)

    Williams, Amy E; Arzola, Gladys Marina; Strutt, Adriana M; Simpson, Richard; Jankovic, Joseph; York, Michele K

    2011-06-01

    Subthalamic nucleus deep brain stimulation (STN-DBS) is currently the treatment of choice for medication-resistant levodopa-related motor complications in patients with Parkinson's disease (PD). While STN-DBS often results in meaningful motor improvements, consensus regarding long-term neuropsychological outcome continues to be debated. We assessed the cognitive outcomes of 19 STN-DBS patients compared to a group of 18 medically-managed PD patients on a comprehensive neuropsychological battery at baseline and two years post-surgery. Patients did not demonstrate changes in global cognitive functioning on screening measures. However, neuropsychological results revealed impairments in nonverbal recall, oral information processing speed, and lexical and semantic fluency in STN-DBS patients compared to PD controls 2 years post-surgery in these preliminary analyses. Additionally, reliable change indices revealed that approximately 50% of STN-DBS patients demonstrated significant declines in nonverbal memory and oral information processing speed compared to 25-30% of PD controls, and 26% of STN-DBS patients declined on lexical fluency compared to 11% of PD patients. Approximately 30% of both groups declined on semantic fluency. The number of STN-DBS patients who converted to dementia 2 years following surgery was not significantly different from the PD participants (32% versus 16%, respectively). Our results suggest that neuropsychological evaluations may identify possible mild cognitive changes following surgery. Copyright © 2011 Elsevier Ltd. All rights reserved.

  6. Evaluating the test-retest reliability of symptom indices associated with the ImPACT post-concussion symptom scale (PCSS).

    Science.gov (United States)

    Merritt, Victoria C; Bradson, Megan L; Meyer, Jessica E; Arnett, Peter A

    2018-05-01

    The Immediate Post-Concussion Assessment and Cognitive Testing (ImPACT) is a commonly used tool in sports concussion assessment. While test-retest reliabilities have been established for the ImPACT cognitive composites, few studies have evaluated the psychometric properties of the ImPACT's Post-Concussion Symptom Scale (PCSS). The purpose of this study was to establish the test-retest reliability of symptom indices associated with the PCSS. Participants included 38 undergraduate students (50.0% male) who underwent neuropsychological testing as part of their participation in their psychology department's research subject pool. The majority of the participants were Caucasian (94.7%) and had no history of concussion (73.7%). All participants completed the ImPACT at two time points, approximately 6 weeks apart. The PCSS was the main outcome measure, and eight symptom indices were calculated (a total symptom score, three symptom summary indices, and four symptom clusters). Pearson correlations (r) and intraclass correlation coefficients (ICCs) were computed as measures of test-retest reliability. Overall, reliabilities ranged from low to high (r = .44 to .80; ICC = .44 to .77). The cognitive symptom cluster exhibited the highest test-retest reliability (r = .80, ICC = .77), followed by the positive symptom total (PST) index, an indicator of the total number of symptoms endorsed (r = .71, ICC = .69). In contrast, the commonly used total symptom score showed lower test-retest reliability (r = .67, ICC = .62). Paired-samples t tests revealed no significant differences between test and retest for any of the symptom variables (all p > .01). Finally, reliable change indices (RCI) were computed to determine whether differences observed between test and retest represented clinically significant change. RCI values were provided for each symptom index at the 80%, 90%, and 95% confidence intervals. These results suggest that evaluating additional symptom

  7. Reliability of temperature signal in various climate indicators from northern Europe.

    Directory of Open Access Journals (Sweden)

    Pertti Hari

    Full Text Available We collected relevant observational and measured annual-resolution time series dealing with climate in northern Europe, focusing in Finland. We analysed these series for the reliability of their temperature signal at annual and seasonal resolutions. Importantly, we analysed all of the indicators within the same statistical framework, which allows for their meaningful comparison. In this framework, we employed a cross-validation procedure designed to reduce the adverse effects of estimation bias that may inflate the reliability of various temperature indicators, especially when several indicators are used in a multiple regression model. In our data sets, timing of phenological observations and ice break-up were connected with spring, tree ring characteristics (width, density, carbon isotopic composition with summer and ice formation with autumn temperatures. Baltic Sea ice extent and the duration of ice cover in different watercourses were good indicators of winter temperatures. Using combinations of various temperature indicator series resulted in reliable temperature signals for each of the four seasons, as well as a reliable annual temperature signal. The results hence demonstrated that we can obtain reliable temperature information over different seasons, using a careful selection of indicators, combining the results with regression analysis, and by determining the reliability of the obtained indicator.

  8. Investigating Reliabilities of Intraindividual Variability Indicators

    Science.gov (United States)

    Wang, Lijuan; Grimm, Kevin J.

    2012-01-01

    Reliabilities of the two most widely used intraindividual variability indicators, "ISD[superscript 2]" and "ISD", are derived analytically. Both are functions of the sizes of the first and second moments of true intraindividual variability, the size of the measurement error variance, and the number of assessments within a burst. For comparison,…

  9. Examining the reliability of ADAS-Cog change scores.

    Science.gov (United States)

    Grochowalski, Joseph H; Liu, Ying; Siedlecki, Karen L

    2016-09-01

    The purpose of this study was to estimate and examine ways to improve the reliability of change scores on the Alzheimer's Disease Assessment Scale, Cognitive Subtest (ADAS-Cog). The sample, provided by the Alzheimer's Disease Neuroimaging Initiative, included individuals with Alzheimer's disease (AD) (n = 153) and individuals with mild cognitive impairment (MCI) (n = 352). All participants were administered the ADAS-Cog at baseline and 1 year, and change scores were calculated as the difference in scores over the 1-year period. Three types of change score reliabilities were estimated using multivariate generalizability. Two methods to increase change score reliability were evaluated: reweighting the subtests of the scale and adding more subtests. Reliability of ADAS-Cog change scores over 1 year was low for both the AD sample (ranging from .53 to .64) and the MCI sample (.39 to .61). Reweighting the change scores from the AD sample improved reliability (.68 to .76), but lengthening provided no useful improvement for either sample. The MCI change scores had low reliability, even with reweighting and adding additional subtests. The ADAS-Cog scores had low reliability for measuring change. Researchers using the ADAS-Cog should estimate and report reliability for their use of the change scores. The ADAS-Cog change scores are not recommended for assessment of meaningful clinical change.

  10. Measuring reliable change in cognition using the Edinburgh Cognitive and Behavioural ALS Screen (ECAS).

    Science.gov (United States)

    Crockford, Christopher; Newton, Judith; Lonergan, Katie; Madden, Caoifa; Mays, Iain; O'Sullivan, Meabhdh; Costello, Emmet; Pinto-Grau, Marta; Vajda, Alice; Heverin, Mark; Pender, Niall; Al-Chalabi, Ammar; Hardiman, Orla; Abrahams, Sharon

    2018-02-01

    Cognitive impairment affects approximately 50% of people with amyotrophic lateral sclerosis (ALS). Research has indicated that impairment may worsen with disease progression. The Edinburgh Cognitive and Behavioural ALS Screen (ECAS) was designed to measure neuropsychological functioning in ALS, with its alternate forms (ECAS-A, B, and C) allowing for serial assessment over time. The aim of the present study was to establish reliable change scores for the alternate forms of the ECAS, and to explore practice effects and test-retest reliability of the ECAS's alternate forms. Eighty healthy participants were recruited, with 57 completing two and 51 completing three assessments. Participants were administered alternate versions of the ECAS serially (A-B-C) at four-month intervals. Intra-class correlation analysis was employed to explore test-retest reliability, while analysis of variance was used to examine the presence of practice effects. Reliable change indices (RCI) and regression-based methods were utilized to establish change scores for the ECAS alternate forms. Test-retest reliability was excellent for ALS Specific, ALS Non-Specific, and ECAS Total scores of the combined ECAS A, B, and C (all > .90). No significant practice effects were observed over the three testing sessions. RCI and regression-based methods produced similar change scores. The alternate forms of the ECAS possess excellent test-retest reliability in a healthy control sample, with no significant practice effects. The use of conservative RCI scores is recommended. Therefore, a change of ≥8, ≥4, and ≥9 for ALS Specific, ALS Non-Specific, and ECAS Total score is required for reliable change.

  11. Assessment and Improving Methods of Reliability Indices in Bakhtar Regional Electricity Company

    Directory of Open Access Journals (Sweden)

    Saeed Shahrezaei

    2013-04-01

    Full Text Available Reliability of a system is the ability of a system to do prospected duties in future and the probability of desirable operation for doing predetermined duties. Power system elements failures data are the main data of reliability assessment in the network. Determining antiseptic parameters is the goal of reliability assessment by using system history data. These parameters help to recognize week points of the system. In other words, the goal of reliability assessment is operation improving and decreasing of the failures and power outages. This paper is developed to assess reliability indices of Bakhtar Regional Electricity Company up to 1393 and the improving methods and their effects on the reliability indices in this network. DIgSILENT Power Factory software is employed for simulation. Simulation results show the positive effect of improving methods in reliability indices of Bakhtar Regional Electricity Company.

  12. Montreal Cognitive Assessment and Mini-Mental State Examination reliable change indices in healthy older adults.

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    Kopecek, Miloslav; Bezdicek, Ondrej; Sulc, Zdenek; Lukavsky, Jiri; Stepankova, Hana

    2017-08-01

    Cognitive tests are used repeatedly to assess the treatment response or progression of cognitive disorders. The Montreal Cognitive Assessment (MoCA) is a valid screening test for mild cognitive impairment. The aim of our study was to establish 90% reliable change indices (RCI) for the MoCA together with the Mini-Mental State Examination (MMSE) in cognitively healthy older adults. We analyzed 197 cognitively healthy and functional independent volunteers aged 60-94 years, who met strict inclusion criteria for four consecutive years. The RCI methods by Chelune and Hsu were used. For 1, 2, and 3 years, the 90% RCI for MoCA using Chelune's formula were -4 ≤, ≥4; -4 ≤, ≥4 and -5 ≤, ≥4 points, respectively, and -3 ≤, ≥3 for the MMSE each year. Ninety percent RCI for MoCA using Hsu's formula ranged from -6 to 0, respectively, and +3 to +8 dependent on the baseline MoCA. Our study demonstrated RCI for the MoCA and MMSE in a 3-year time period that can be used for the estimation of cognitive decline or improvement in clinical settings. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

  13. Reliability of flipper-banded penguins as indicators of climate change.

    Science.gov (United States)

    Saraux, Claire; Le Bohec, Céline; Durant, Joël M; Viblanc, Vincent A; Gauthier-Clerc, Michel; Beaune, David; Park, Young-Hyang; Yoccoz, Nigel G; Stenseth, Nils C; Le Maho, Yvon

    2011-01-13

    In 2007, the Intergovernmental Panel on Climate Change highlighted an urgent need to assess the responses of marine ecosystems to climate change. Because they lie in a high-latitude region, the Southern Ocean ecosystems are expected to be strongly affected by global warming. Using top predators of this highly productive ocean (such as penguins) as integrative indicators may help us assess the impacts of climate change on marine ecosystems. Yet most available information on penguin population dynamics is based on the controversial use of flipper banding. Although some reports have found the effects of flipper bands to be deleterious, some short-term (one-year) studies have concluded otherwise, resulting in the continuation of extensive banding schemes and the use of data sets thus collected to predict climate impact on natural populations. Here we show that banding of free-ranging king penguins (Aptenodytes patagonicus) impairs both survival and reproduction, ultimately affecting population growth rate. Over the course of a 10-year longitudinal study, banded birds produced 41% [corrected] fewer chicks and had a survival rate 16 percentage points [corrected] lower than non-banded birds, demonstrating a massive long-term impact of banding and thus refuting the assumption that birds will ultimately adapt to being banded. Indeed, banded birds still arrived later for breeding at the study site and had longer foraging trips even after 10 years. One of our major findings is that responses of flipper-banded penguins to climate variability (that is, changes in sea surface temperature and in the Southern Oscillation index) differ from those of non-banded birds. We show that only long-term investigations may allow an evaluation of the impact of flipper bands and that every major life-history trait can be affected, calling into question the banding schemes still going on. In addition, our understanding of the effects of climate change on marine ecosystems based on flipper

  14. Seven Reliability Indices for High-Stakes Decision Making: Description, Selection, and Simple Calculation

    Science.gov (United States)

    Smith, Stacey L.; Vannest, Kimberly J.; Davis, John L.

    2011-01-01

    The reliability of data is a critical issue in decision-making for practitioners in the school. Percent Agreement and Cohen's kappa are the two most widely reported indices of inter-rater reliability, however, a recent Monte Carlo study on the reliability of multi-category scales found other indices to be more trustworthy given the type of data…

  15. Establishing reliability of performance indicator of sepak takraw ...

    African Journals Online (AJOL)

    The aim of this study is to establish the necessary reliability in the notational analysis of sepak takraw. Two performance analysts were recruited to help in the collection of the data. The performances were analyzed based on the main performance indicators relevant to the demand of the game. Cronbach's alpha and ...

  16. Reliability Indicators of Urban Electric Network Schemes for Supply of Second and Third Category Consumers

    Directory of Open Access Journals (Sweden)

    M. A. Korotkevich

    2012-01-01

    Full Text Available The paper considers two schemes of the urban distributive electric network for supply of the second and third category consumers for whom indicators of reliability have been determined.As for a network scheme of the 2nd category it has been determined that while installing low-oil and vacuum switches at a distributive point the most remote transformer substation has the highest non-availability  factor which is higher of the corresponding non-availability  factor of the nearest transformer substation by 1,21–1,23 fold  accordingly.As for a network scheme of the 3rd category consumers it has been obtained the data that reliability of consumers receiving supply from bus-bars of transformer substations with 0,38 kW voltage changes  significantly (by 1,2–1,9-fold while changing a breakpoint of the network with 10 kW voltage.

  17. The Test-Retest Reliability of New Generation Power Indices of Wingate All-Out Test

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    Ozgur Ozkaya

    2018-04-01

    Full Text Available Although reliability correlations of traditional power indices of the Wingate test have been well documented, no study has analyzed new generation power indices based on milliseconds obtained from a Peak Bike. The purpose of this study was to investigate the retest reliability of new generation power indices. Thirty-two well-trained male athletes who were specialized in basketball, football, tennis, or track and field volunteered to take part in the study (age: 24.3 ± 2.2 years; body mass: 77 ± 8.3 kg; height: 180.3 ± 6.3 cm. Participants performed two Wingate all-out sessions on two separate days. Intra-class correlation coefficient (ICC, standard error measurement (SEM, smallest real differences (SRD and coefficient of variation (CV scores were analyzed based on the test and retest data. Reliability results of traditional power indices calculated based on 5-s means such as peak power, average power, power drop, and fatigue index ratio were similar with the previous findings in literature (ICC ≥ 0.94; CV ≤ 2.8%; SEM ≤ 12.28; SRD% ≤ 7.7%. New generation power indices such as peak power, average power, lowest power, power drop, fatigue index, power decline, maximum speed as rpm, and amount of total energy expenditure demonstrated high reliability (ICC ≥ 0.94; CV ≤ 4.3%; SEM ≤ 10.36; SRD% ≤ 8.8%. Time to peak power, time at maximum speed, and power at maximum speed showed a moderate level of reliability (ICC ≥ 0.73; CV ≤ 8.9%; SEM ≤ 63.01; SRD% ≤ 22.4%. The results of this study indicate that reliability correlations and SRD% of new generation power and fatigue-related indices are similar with traditional 5-s means. However, new time-related indices are very sensitive and moderately reliable.

  18. An Indication of Reliability of the Two-Level Approach of the AWIN Welfare Assessment Protocol for Horses

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    Irena Czycholl

    2018-01-01

    Full Text Available To enhance feasibility, the Animal Welfare Indicators (AWIN assessment protocol for horses consists of two levels: the first is a visual inspection of a sample of horses performed from a distance, the second a close-up inspection of all horses. The aim was to analyse whether information would be lost if only the first level were performed. In this study, 112 first and 112 second level assessments carried out on a subsequent day by one observer were compared by calculating the Spearman’s Rank Correlation Coefficient (RS, Intraclass Correlation Coefficients (ICC, Smallest Detectable Changes (SDC and Limits of Agreements (LoA. Most indicators demonstrated sufficient reliability between the two levels. Exceptions were the Horse Grimace Scale, the Avoidance Distance Test and the Voluntary Human Approach Test (e.g., Voluntary Human Approach Test: RS: 0.38, ICC: 0.38, SDC: 0.21, LoA: −0.25–0.17, which could, however, be also interpreted as a lack of test-retest reliability. Further disagreement was found for the indicator consistency of manure (RS: 0.31, ICC: 0.38, SDC: 0.36, LoA: −0.38–0.36. For these indicators, an adaptation of the first level would be beneficial. Overall, in this study, the division into two levels was reliable and might therewith have the potential to enhance feasibility in other welfare assessment schemes.

  19. Inter-observer reliability of animal-based welfare indicators included in the Animal Welfare Indicators welfare assessment protocol for dairy goats.

    Science.gov (United States)

    Vieira, A; Battini, M; Can, E; Mattiello, S; Stilwell, G

    2018-01-08

    This study was conducted within the context of the Animal Welfare Indicators (AWIN) project and the underlying scientific motivation for the development of the study was the scarcity of data regarding inter-observer reliability (IOR) of welfare indicators, particularly given the importance of reliability as a further step for developing on-farm welfare assessment protocols. The objective of this study is therefore to evaluate IOR of animal-based indicators (at group and individual-level) of the AWIN welfare assessment protocol (prototype) for dairy goats. In the design of the study, two pairs of observers, one in Portugal and another in Italy, visited 10 farms each and applied the AWIN prototype protocol. Farms in both countries were visited between January and March 2014, and all the observers received the same training before the farm visits were initiated. Data collected during farm visits, and analysed in this study, include group-level and individual-level observations. The results of our study allow us to conclude that most of the group-level indicators presented the highest IOR level ('substantial', 0.85 to 0.99) in both field studies, pointing to a usable set of animal-based welfare indicators that were therefore included in the first level of the final AWIN welfare assessment protocol for dairy goats. Inter-observer reliability of individual-level indicators was lower, but the majority of them still reached 'fair to good' (0.41 to 0.75) and 'excellent' (0.76 to 1) levels. In the paper we explore reasons for the differences found in IOR between the group and individual-level indicators, including how the number of individual-level indicators to be assessed on each animal and the restraining method may have affected the results. Furthermore, we discuss the differences found in the IOR of individual-level indicators in both countries: the Portuguese pair of observers reached a higher level of IOR, when compared with the Italian observers. We argue how the

  20. Phytoplankton community indicators of changes associated with dredging in the Tagus estuary (Portugal)

    International Nuclear Information System (INIS)

    Cabrita, Maria Teresa

    2014-01-01

    This work reports changes in suspended particulate matter, turbidity, dissolved Cr, Ni, Cu, Cd, Hg and Pb concentrations, and phytoplankton biomass and composition during a 5-month period dredging operation, in a trace element contaminated area of the Tagus estuary (Portugal). Phytoplankton biomass, diatom:other groups ratio, benthic:pelagic diatom ratio, Margalef's, Simpson's diversity, Shannon–Wiever's, and Warwick and Clarke's taxonomic diversity and distinctness indices, and individual taxa were investigated as indicators of dredging induced changes. Significant rise in sediment resuspension and trace element mobilisation caused by dredging influenced the community structure but not the overall biomass. Benthic diatom displacement into the water column maintained species diversity, and therefore, none of the indices highlighted community changes. Contrastingly, diatom:other groups ratio and benthic:pelagic diatom ratio were reliable indicators for the assessment of dredging induced changes. A shift in composition towards species less susceptible to trace elements was observed, disclosing some individual taxa as potential indicators. - Highlights: • Phytoplankton community indicators of dredging induced changes were investigated. • Increased resuspension and trace element mobilisation changed community structure. • Diversity indices unsuitable to detect changes because species richness was maintained. • Diatom:other groups and benthic:pelagic diatom ratios were efficient indicators. • Individual taxa may be potential indicators but require site-specific validation. - Diatom:other groups ratio, benthic:pelagic diatom ratio and individual taxa were identified as efficient indicators for the assessment of water quality changes associated with dredging

  1. Inter-rater reliability of nursing home quality indicators in the U.S

    Directory of Open Access Journals (Sweden)

    Roy Jason

    2003-11-01

    Full Text Available Abstract Background In the US, Quality Indicators (QI's profiling and comparing the performance of hospitals, health plans, nursing homes and physicians are routinely published for consumer review. We report the results of the largest study of inter-rater reliability done on nursing home assessments which generate the data used to derive publicly reported nursing home quality indicators. Methods We sampled nursing homes in 6 states, selecting up to 30 residents per facility who were observed and assessed by research nurses on 100 clinical assessment elements contained in the Minimum Data Set (MDS and compared these with the most recent assessment in the record done by facility nurses. Kappa statistics were generated for all data items and derived for 22 QI's over the entire sample and for each facility. Finally, facilities with many QI's with poor Kappa levels were compared to those with many QI's with excellent Kappa levels on selected characteristics. Results A total of 462 facilities in 6 states were approached and 219 agreed to participate, yielding a response rate of 47.4%. A total of 5758 residents were included in the inter-rater reliability analyses, around 27.5 per facility. Patients resembled the traditional nursing home resident, only 43.9% were continent of urine and only 25.2% were rated as likely to be discharged within the next 30 days. Results of resident level comparative analyses reveal high inter-rater reliability levels (most items >.75. Using the research nurses as the "gold standard", we compared composite quality indicators based on their ratings with those based on facility nurses. All but two QI's have adequate Kappa levels and 4 QI's have average Kappa values in excess of .80. We found that 16% of participating facilities performed poorly (Kappa .75 on 12 or more QI's. No facility characteristics were related to reliability of the data on which Qis are based. Conclusion While a few QI's being used for public reporting

  2. The assessment of changes in cognitive functioning: age-, education-, and gender-specific reliable change indices for older adults tested on the CERAD-NP battery: results of the German Study on Ageing, Cognition, and Dementia in Primary Care Patients (AgeCoDe).

    Science.gov (United States)

    Stein, Janine; Luppa, Melanie; Luck, Tobias; Maier, Wolfgang; Wagner, Michael; Daerr, Moritz; van den Bussche, Hendrik; Zimmermann, Thomas; Köhler, Mirjam; Bickel, Horst; Mösch, Edelgard; Weyerer, Siegfried; Kaufeler, Teresa; Pentzek, Michael; Wiese, Birgitt; Wollny, Anja; König, Hans-Helmut; Riedel-Heller, Steffi G

    2012-01-01

    The Consortium to Establish a Registry for Alzheimer's Disease-Neuropsychological (CERAD-NP) battery represents a commonly used neuropsychological instrument to measure cognitive functioning in the elderly. This study provides normative data for changes in cognitive function that normally occur in cognitively healthy individuals to interpret changes in CERAD-NP test scores over longer time periods. Longitudinal cohort study with three assessments at 1.5-year intervals over a period of 3 years. : Primary care medical record registry sample. As part of the German Study on Ageing, Cognition, and Dementia in Primary Care Patients, a sample of 1,450 cognitively healthy general practitioner patients, age 75 years and older, was assessed. Age-, education-, and gender-specific Reliable Change Indices (RCIs) were computed for a 90% confidence interval for selected subtests of the CERAD-NP battery. Across different age, education, and gender subgroups, changes from at least six to nine points in Verbal Fluency, four to eight points in Word List Memory, two to four points in Word List Recall, and one to four points in Word List Recognition indicated significant (i.e. reliable) changes in CERAD-NP test scores at the 90% confidence level. Furthermore, the calculation of RCIs for individual patients is demonstrated. Smaller changes in CERAD-NP test scores can be interpreted with only high uncertainty because of probable measurement error, practice effects, and normal age-related cognitive decline. This study, for the first time, provides age-, education-, and gender-specific CERAD-NP reference values on the basis of RCI methods for the interpretation of cognitive changes in older-age groups.

  3. Reliability concepts applied to cutting tool change time

    Energy Technology Data Exchange (ETDEWEB)

    Patino Rodriguez, Carmen Elena, E-mail: cpatino@udea.edu.c [Department of Industrial Engineering, University of Antioquia, Medellin (Colombia); Department of Mechatronics and Mechanical Systems, Polytechnic School, University of Sao Paulo, Sao Paulo (Brazil); Francisco Martha de Souza, Gilberto [Department of Mechatronics and Mechanical Systems, Polytechnic School, University of Sao Paulo, Sao Paulo (Brazil)

    2010-08-15

    This paper presents a reliability-based analysis for calculating critical tool life in machining processes. It is possible to determine the running time for each tool involved in the process by obtaining the operations sequence for the machining procedure. Usually, the reliability of an operation depends on three independent factors: operator, machine-tool and cutting tool. The reliability of a part manufacturing process is mainly determined by the cutting time for each job and by the sequence of operations, defined by the series configuration. An algorithm is presented to define when the cutting tool must be changed. The proposed algorithm is used to evaluate the reliability of a manufacturing process composed of turning and drilling operations. The reliability of the turning operation is modeled based on data presented in the literature, and from experimental results, a statistical distribution of drilling tool wear was defined, and the reliability of the drilling process was modeled.

  4. Reliability concepts applied to cutting tool change time

    International Nuclear Information System (INIS)

    Patino Rodriguez, Carmen Elena; Francisco Martha de Souza, Gilberto

    2010-01-01

    This paper presents a reliability-based analysis for calculating critical tool life in machining processes. It is possible to determine the running time for each tool involved in the process by obtaining the operations sequence for the machining procedure. Usually, the reliability of an operation depends on three independent factors: operator, machine-tool and cutting tool. The reliability of a part manufacturing process is mainly determined by the cutting time for each job and by the sequence of operations, defined by the series configuration. An algorithm is presented to define when the cutting tool must be changed. The proposed algorithm is used to evaluate the reliability of a manufacturing process composed of turning and drilling operations. The reliability of the turning operation is modeled based on data presented in the literature, and from experimental results, a statistical distribution of drilling tool wear was defined, and the reliability of the drilling process was modeled.

  5. Reliability of a Test Battery Designed for Quickly and Safely Assessing Diverse Indices of Neuromuscular Function

    Science.gov (United States)

    Spiering, Barry A.; Lee, Stuart M. C.; Mulavara, Ajitkumar P.; Bentley, Jason, R.; Buxton, Roxanne E.; Lawrence, Emily L.; Sinka, Joseph; Guilliams, Mark E.; Ploutz-Snyder, Lori L.; Bloomberg, Jacob J.

    2010-01-01

    Spaceflight affects nearly every physiological system. Spaceflight-induced alterations in physiological function translate to decrements in functional performance. Purpose: To develop a test battery for quickly and safely assessing diverse indices of neuromuscular performance. I. Quickly: Battery of tests can be completed in approx.30-40 min. II. Safely: a) No eccentric muscle actions or impact forces. b) Tests present little challenge to postural stability. III. Diverse indices: a) Strength: Excellent reliability (ICC = 0.99) b) Central activation: Very good reliability (ICC = 0.87) c) Power: Excellent reliability (ICC = 0.99) d) Endurance: Total work has excellent reliability (ICC = 0.99) e) Force steadiness: Poor reliability (ICC = 0.20 - 0.60) National

  6. The influence of different error estimates in the detection of postoperative cognitive dysfunction using reliable change indices with correction for practice effects.

    Science.gov (United States)

    Lewis, Matthew S; Maruff, Paul; Silbert, Brendan S; Evered, Lis A; Scott, David A

    2007-02-01

    The reliable change index (RCI) expresses change relative to its associated error, and is useful in the identification of postoperative cognitive dysfunction (POCD). This paper examines four common RCIs that each account for error in different ways. Three rules incorporate a constant correction for practice effects and are contrasted with the standard RCI that had no correction for practice. These rules are applied to 160 patients undergoing coronary artery bypass graft (CABG) surgery who completed neuropsychological assessments preoperatively and 1 week postoperatively using error and reliability data from a comparable healthy nonsurgical control group. The rules all identify POCD in a similar proportion of patients, but the use of the within-subject standard deviation (WSD), expressing the effects of random error, as an error estimate is a theoretically appropriate denominator when a constant error correction, removing the effects of systematic error, is deducted from the numerator in a RCI.

  7. Confidence Estimation of Reliability Indices of the System with Elements Duplication and Recovery

    Directory of Open Access Journals (Sweden)

    I. V. Pavlov

    2017-01-01

    Full Text Available The article considers a problem to estimate a confidence interval of the main reliability indices such as availability rate, mean time between failures, and operative availability (in the stationary state for the model of the system with duplication and independent recovery of elements.Presents a solution of the problem for a situation that often arises in practice, when there are unknown exact values of the reliability parameters of the elements, and only test data of the system or its individual parts (elements, subsystems for reliability are known. It should be noted that the problems of the confidence estimate of reliability indices of the complex systems based on the testing results of their individual elements are fairly common function in engineering practice when designing and running the various engineering systems. The available papers consider this problem, mainly, for non-recovery systems.Describes a solution of this problem for the important particular case when the system elements are duplicated by the reserved elements, and the elements that have failed in the course of system operation are recovered (regardless of the state of other elements.An approximate solution of this problem is obtained for the case of high reliability or "fast recovery" of elements on the assumption that the average recovery time of elements is small as compared to the average time between failures.

  8. Climate Change Indicators

    Science.gov (United States)

    Presents information, charts and graphs showing measured climate changes across 40 indicators related to greenhouse gases, weather and climate, oceans, snow and ice, heath and society, and ecosystems.

  9. Operator adaptation to changes in system reliability under adaptable automation.

    Science.gov (United States)

    Chavaillaz, Alain; Sauer, Juergen

    2017-09-01

    This experiment examined how operators coped with a change in system reliability between training and testing. Forty participants were trained for 3 h on a complex process control simulation modelling six levels of automation (LOA). In training, participants either experienced a high- (100%) or low-reliability system (50%). The impact of training experience on operator behaviour was examined during a 2.5 h testing session, in which participants either experienced a high- (100%) or low-reliability system (60%). The results showed that most operators did not often switch between LOA. Most chose an LOA that relieved them of most tasks but maintained their decision authority. Training experience did not have a strong impact on the outcome measures (e.g. performance, complacency). Low system reliability led to decreased performance and self-confidence. Furthermore, complacency was observed under high system reliability. Overall, the findings suggest benefits of adaptable automation because it accommodates different operator preferences for LOA. Practitioner Summary: The present research shows that operators can adapt to changes in system reliability between training and testing sessions. Furthermore, it provides evidence that each operator has his/her preferred automation level. Since this preference varies strongly between operators, adaptable automation seems to be suitable to accommodate these large differences.

  10. Investigation of reliability indicators of information analysis systems based on Markov’s absorbing chain model

    Science.gov (United States)

    Gilmanshin, I. R.; Kirpichnikov, A. P.

    2017-09-01

    In the result of study of the algorithm of the functioning of the early detection module of excessive losses, it is proven the ability to model it by using absorbing Markov chains. The particular interest is in the study of probability characteristics of early detection module functioning algorithm of losses in order to identify the relationship of indicators of reliability of individual elements, or the probability of occurrence of certain events and the likelihood of transmission of reliable information. The identified relations during the analysis allow to set thresholds reliability characteristics of the system components.

  11. Statistical Primer for Athletic Trainers: The Essentials of Understanding Measures of Reliability and Minimal Important Change.

    Science.gov (United States)

    Riemann, Bryan L; Lininger, Monica R

    2018-01-01

      To describe the concepts of measurement reliability and minimal important change.   All measurements have some magnitude of error. Because clinical practice involves measurement, clinicians need to understand measurement reliability. The reliability of an instrument is integral in determining if a change in patient status is meaningful.   Measurement reliability is the extent to which a test result is consistent and free of error. Three perspectives of reliability-relative reliability, systematic bias, and absolute reliability-are often reported. However, absolute reliability statistics, such as the minimal detectable difference, are most relevant to clinicians because they provide an expected error estimate. The minimal important difference is the smallest change in a treatment outcome that the patient would identify as important.   Clinicians should use absolute reliability characteristics, preferably the minimal detectable difference, to determine the extent of error around a patient's measurement. The minimal detectable difference, coupled with an appropriately estimated minimal important difference, can assist the practitioner in identifying clinically meaningful changes in patients.

  12. Test-Retest Reliability and Minimal Detectable Change of Randomized Dichotic Digits in Learning-Disabled Children: Implications for Dichotic Listening Training.

    Science.gov (United States)

    Mahdavi, Mohammad Ebrahim; Pourbakht, Akram; Parand, Akram; Jalaie, Shohreh

    2018-03-01

    Evaluation of dichotic listening to digits is a common part of many studies for diagnosis and managing auditory processing disorders in children. Previous researchers have verified test-retest relative reliability of dichotic digits results in normal children and adults. However, detecting intervention-related changes in the ear scores after dichotic listening training requires information regarding trial-to-trial typical variation of individual ear scores that is estimated using indices of absolute reliability. Previous studies have not addressed absolute reliability of dichotic listening results. To compare the results of the Persian randomized dichotic digits test (PRDDT) and its relative and absolute indices of reliability between typical achieving (TA) and learning-disabled (LD) children. A repeated measures observational study. Fifteen LD children were recruited from a previously performed study with age range of 7-12 yr. The control group consisted of 15 TA schoolchildren with age range of 8-11 yr. The Persian randomized dichotic digits test was administered on the children under free recall condition in two test sessions 7-12 days apart. We compared the average of the ear scores and ear advantage between TA and LD children. Relative indices of reliability included Pearson's correlation and intraclass correlation (ICC 2,1 ) coefficients and absolute reliability was evaluated by calculation of standard error of measurement (SEM) and minimal detectable change (MDC) using the raw ear scores. The Pearson correlation coefficient indicated that in both groups of children the ear scores of test and retest sessions were strongly and positively (greater than +0.8) correlated. The ear scores showed excellent ICC coefficient of consistency (0.78-0.82) and fair to excellent ICC coefficient of absolute agreement (0.62-0.74) in TA children and excellent ICC coefficients of consistency and absolute agreement in LD children (0.76-0.87). SEM and SEM% of the ear scores in TA

  13. Reliability and usability of tourism climate indices

    Directory of Open Access Journals (Sweden)

    Ghislain Dubois

    2016-04-01

    Full Text Available Abstract Tourism climate indices (TCI are commonly used to describe the climate conditions suitable for tourism activities, from the planning, investment or daily operations perspectives. A substantial amount of research has been carried out, in particular with respect to new indices formulae adapted to specific tourism products, and parameters and their weighting, taking into account surveys on the stated preferences of tourists, especially in terms of comfort. This paper illustrates another field of research, which seeks to better understand the different sources of uncertainty associated with indices. Indeed, slight differences in formula thresholds, variations in computation methods, and also the use of multimodel ensembles create nuances that affect the ways in which indices projections are usually presented. Firstly, we assess the impact of differences in preference surveys on the definition of indices thresholds, in particular for thermal comfort. Secondly, we compare computation methods for France, showing the need to better specify detailed data sources and their use to ensure the comparability of results. Thirdly, using multimodel ensembles for the Mediterranean basin, we assess the uncertainty inherent in long-term projections, which are used in modelling the economic impact of climate change. This paper argues in favour of a more cautious use of tourism comfort indices, with more consideration given to the robustness of data (validation, debiasing, uncertainty assessment, etc. and users’ needs, from the climate services perspective.

  14. Indicators of Ecological Change

    Science.gov (United States)

    2005-03-01

    H. 1990. Strategy for monitoring the effects of land use change on atmospheric CO2 concentrations . In Proceedings of “Global Natural Resource...Working Group in Santiago , Chile , February 1995, ten nations agreed to a comprehensive set of criteria and indicators for forest conservation and...chemistry variables, the concentrations of total and inorganic suspended sediments during baseflow and storm periods were excellent indicators of

  15. Reading for Reliability: Preservice Teachers Evaluate Web Sources about Climate Change

    Science.gov (United States)

    Damico, James S.; Panos, Alexandra

    2016-01-01

    This study examined what happened when 65 undergraduate prospective secondary level teachers across content areas evaluated the reliability of four online sources about climate change: an oil company webpage, a news report, and two climate change organizations with competing views on climate change. The students evaluated the sources at three time…

  16. Reliability and Minimum Detectable Change of Temporal-Spatial, Kinematic, and Dynamic Stability Measures during Perturbed Gait.

    Directory of Open Access Journals (Sweden)

    Christopher A Rábago

    Full Text Available Temporal-spatial, kinematic variability, and dynamic stability measures collected during perturbation-based assessment paradigms are often used to identify dysfunction associated with gait instability. However, it remains unclear which measures are most reliable for detecting and tracking responses to perturbations. This study systematically determined the between-session reliability and minimum detectable change values of temporal-spatial, kinematic variability, and dynamic stability measures during three types of perturbed gait. Twenty young healthy adults completed two identical testing sessions two weeks apart, comprised of an unperturbed and three perturbed (cognitive, physical, and visual walking conditions in a virtual reality environment. Within each session, perturbation responses were compared to unperturbed walking using paired t-tests. Between-session reliability and minimum detectable change values were also calculated for each measure and condition. All temporal-spatial, kinematic variability and dynamic stability measures demonstrated fair to excellent between-session reliability. Minimal detectable change values, normalized to mean values ranged from 1-50%. Step width mean and variability measures demonstrated the greatest response to perturbations with excellent between-session reliability and low minimum detectable change values. Orbital stability measures demonstrated specificity to perturbation direction and sensitivity with excellent between-session reliability and low minimum detectable change values. We observed substantially greater between-session reliability and lower minimum detectable change values for local stability measures than previously described which may be the result of averaging across trials within a session and using velocity versus acceleration data for reconstruction of state spaces. Across all perturbation types, temporal-spatial, orbital and local measures were the most reliable measures with the

  17. Climate change indicators in the United States

    Science.gov (United States)

    2010-04-01

    The U.S. Environmental Protection Agency (EPA) has published this report, Climate Change Indicators in the United States, to help readers interpret a set of important indicators to better understand climate change. The report presents 24 indicators, ...

  18. Village-level supply reliability of surface water irrigation in rural China: effects of climate change

    Science.gov (United States)

    Li, Yanrong; Wang, Jinxia

    2018-06-01

    Surface water, as the largest part of water resources, plays an important role on China's agricultural production and food security. And surface water is vulnerable to climate change. This paper aims to examine the status of the supply reliability of surface water irrigation, and discusses how it is affected by climate change in rural China. The field data we used in this study was collected from a nine-province field survey during 2012 and 2013. Climate data are offered by China's National Meteorological Information Center which contains temperature and precipitation in the past 30 years. A Tobit model (or censored regression model) was used to estimate the influence of climate change on supply reliability of surface water irrigation. Descriptive results showed that, surface water supply reliability was 74 % in the past 3 years. Econometric results revealed that climate variables significantly influenced the supply reliability of surface water irrigation. Specifically, temperature is negatively related with the supply reliability of surface water irrigation; but precipitation positively influences the supply reliability of surface water irrigation. Besides, climate influence differs by seasons. In a word, this paper improves our understanding of the impact of climate change on agriculture irrigation and water supply reliability in the micro scale, and provides a scientific basis for relevant policy making.

  19. Reliability analysis of stiff versus flexible piping

    International Nuclear Information System (INIS)

    Lu, S.C.

    1985-01-01

    The overall objective of this research project is to develop a technical basis for flexible piping designs which will improve piping reliability and minimize the use of pipe supports, snubbers, and pipe whip restraints. The current study was conducted to establish the necessary groundwork based on the piping reliability analysis. A confirmatory piping reliability assessment indicated that removing rigid supports and snubbers tends to either improve or affect very little the piping reliability. The authors then investigated a couple of changes to be implemented in Regulatory Guide (RG) 1.61 and RG 1.122 aimed at more flexible piping design. They concluded that these changes substantially reduce calculated piping responses and allow piping redesigns with significant reduction in number of supports and snubbers without violating ASME code requirements. Furthermore, the more flexible piping redesigns are capable of exhibiting reliability levels equal to or higher than the original stiffer design. An investigation of the malfunction of pipe whip restraints confirmed that the malfunction introduced higher thermal stresses and tended to reduce the overall piping reliability. Finally, support and component reliabilities were evaluated based on available fragility data. Results indicated that the support reliability usually exhibits a moderate decrease as the piping flexibility increases. Most on-line pumps and valves showed an insignificant reduction in reliability for a more flexible piping design

  20. ACSC Indicator: testing reliability for hypertension.

    Science.gov (United States)

    Walker, Robin L; Ghali, William A; Chen, Guanmin; Khalsa, Tej K; Mangat, Birinder K; Campbell, Norm R C; Dixon, Elijah; Rabi, Doreen; Jette, Nathalie; Dhanoa, Robyn; Quan, Hude

    2017-06-26

    With high-quality community-based primary care, hospitalizations for ambulatory care sensitive conditions (ACSC) are considered avoidable. The purpose of this study was to test the inter-physician reliability of judgments of avoidable hospitalizations for one ACSC, uncomplicated hypertension, derived from medical chart review. We applied the Canadian Institute for Health Information's case definition to obtain a random sample of patients who had an ACSC hospitalization for uncomplicated hypertension in Calgary, Alberta. Medical chart review was conducted by three experienced internal medicine specialists. Implicit methods were used to judge avoidability of hospitalization using a validated 5-point scale. There was poor agreement among three physicians raters when judging the avoidability of 82 ACSC hospitalizations for uncomplicated hypertension (κ = 0.092). The κ also remained low when assessing agreement between raters 1 and 3 (κ = 0.092), but the κ was lower (less than chance agreement) for raters 1 and 2 (κ = -0.119) and raters 2 and 3 (κ = -0.008). When the 5-point scale was dichotomized, there was fair agreement among three raters (κ = 0.217). The proportion of ACSC hospitalizations for uncomplicated hypertension that were rated as avoidable was 32.9%, 6.1% and 26.8% for raters 1, 2, and 3, respectively. This study found a low proportion of ACSC hospitalization were rated as avoidable, with poor to fair agreement of judgment between physician raters. This suggests that the validity and utility of this health indicator is questionable. It points to a need to abandon the use of ACSC entirely; or alternatively to work on the development of explicit criteria for judging avoidability of hospitalization for ACSC such as hypertension.

  1. CCME Climate Change Indicators -- Workshop Report

    International Nuclear Information System (INIS)

    2000-01-01

    In an effort to give Canadians a better understanding of the climate change issue, in 1999 the Canadian Council of Ministers of the Environment (CCME) established a Project Working Group to identify and assemble a set of climate change indicators that is scientifically valid, useful and meaningful to the public. To ensure the widest possible participation of experts from all parts of the country the Project Working Group convened a two-day workshop in Toronto to take place on the 6th and 7th of November 2000. The outcome of the workshop, summarized in this report, resulted in a 'Made in Canada' framework of indicators for climate change impacts, divided into five categories: physical environment, personal health and safety, jobs and economic well-being, social and community well-being, and eco-system health. The report contains highlights of the discussions. There are seven appendices containing, respectively, a series of pre-workshop suggestions for indicators (Appendix A), the workshop agenda and backgrounder (Appendix B), a list of participants (Appendix C), presentation slides on the Canada country study (Appendix D), existing and proposed climate change indicators (Appendix E), presentation slides on communication issues (Appendix F), and notes summarizing small group discussions, including assessment of the level of interest demonstrated and opinions expressed by group members about the utility and value of each of the proposed indicators (Appendix G)

  2. Changes of Some Indices of Low Flow affected by Climate Change in the Tang Panj Sezar Basin

    Directory of Open Access Journals (Sweden)

    M. Mozayyan

    2016-10-01

    different variations for different months, also within a month for different GCMs. Based on the results of low flow indices, in most cases, the three indices of Q70, Q90, and Q95 will show incremental changes in the future compared to the past. Also, the domain simulation by 10 GCMs for all three indices is maximum in Tang Panj Sezar and less for other sub catchments, which is related to better performance of IHACRES model in smaller sub catchments. In order to investigate the uncertainty of type changes in different indices in every sub catchment, changes in any of the indices were considered based on the median of GCMs. To achieve the correct type of changes in low flow indices, the amount of error in a simulation of the indices of IHACRES rainfall-runoff model should also be taken into consideration. Therefore, considering the error, the three indices Q70, Q90 and Q95 in all sub catchments (except for Tang Panj Sezar will have the relative increase in the future period. The improvement of low flow state in the future period is related to the changes occurred in the state of climate scenarios. As the results indicated, most often, there is an increase in rainfall in dry seasons. Also, in different months of the wet season wet season, if the result of changes in quantity of rainfall is incremental, it can lead to an increase in river flow through groundwater recharge. On the other hand due to the limestone and karst forms in most of the basin area, water storage ability and increase the amount of river flow during low water season in this area is expected. The study on rainfall quantity in Tang Panj Sezar sub catchment also indicated that, there will be no significant increase or decrease in the quantity of rainfall in the dry season. Thus, it is expected that there will not be significant changes in low flow indices. In this sub catchment, changes in various low flow indices do not match perfectly, so more difficult to obtain reliable results. With regard to incremental

  3. 18 CFR 39.10 - Changes to an Electric Reliability Organization Rule or Regional Entity Rule.

    Science.gov (United States)

    2010-04-01

    ... RULES CONCERNING CERTIFICATION OF THE ELECTRIC RELIABILITY ORGANIZATION; AND PROCEDURES FOR THE ESTABLISHMENT, APPROVAL, AND ENFORCEMENT OF ELECTRIC RELIABILITY STANDARDS § 39.10 Changes to an Electric... Reliability Organization Rule or Regional Entity Rule. 39.10 Section 39.10 Conservation of Power and Water...

  4. Reliability, standard error, and minimum detectable change of clinical pressure pain threshold testing in people with and without acute neck pain.

    Science.gov (United States)

    Walton, David M; Macdermid, Joy C; Nielson, Warren; Teasell, Robert W; Chiasson, Marco; Brown, Lauren

    2011-09-01

    Clinical measurement. To evaluate the intrarater, interrater, and test-retest reliability of an accessible digital algometer, and to determine the minimum detectable change in normal healthy individuals and a clinical population with neck pain. Pressure pain threshold testing may be a valuable assessment and prognostic indicator for people with neck pain. To date, most of this research has been completed using algometers that are too resource intensive for routine clinical use. Novice raters (physiotherapy students or clinical physiotherapists) were trained to perform algometry testing over 2 clinically relevant sites: the angle of the upper trapezius and the belly of the tibialis anterior. A convenience sample of normal healthy individuals and a clinical sample of people with neck pain were tested by 2 different raters (all participants) and on 2 different days (healthy participants only). Intraclass correlation coefficient (ICC), standard error of measurement, and minimum detectable change were calculated. A total of 60 healthy volunteers and 40 people with neck pain were recruited. Intrarater reliability was almost perfect (ICC = 0.94-0.97), interrater reliability was substantial to near perfect (ICC = 0.79-0.90), and test-retest reliability was substantial (ICC = 0.76-0.79). Smaller change was detectable in the trapezius compared to the tibialis anterior. This study provides evidence that novice raters can perform digital algometry with adequate reliability for research and clinical use in people with and without neck pain.

  5. Reliability of Coulomb stress changes inferred from correlated uncertainties of finite-fault source models

    KAUST Repository

    Woessner, J.

    2012-07-14

    Static stress transfer is one physical mechanism to explain triggered seismicity. Coseismic stress-change calculations strongly depend on the parameterization of the causative finite-fault source model. These models are uncertain due to uncertainties in input data, model assumptions, and modeling procedures. However, fault model uncertainties have usually been ignored in stress-triggering studies and have not been propagated to assess the reliability of Coulomb failure stress change (ΔCFS) calculations. We show how these uncertainties can be used to provide confidence intervals for co-seismic ΔCFS-values. We demonstrate this for the MW = 5.9 June 2000 Kleifarvatn earthquake in southwest Iceland and systematically map these uncertainties. A set of 2500 candidate source models from the full posterior fault-parameter distribution was used to compute 2500 ΔCFS maps. We assess the reliability of the ΔCFS-values from the coefficient of variation (CV) and deem ΔCFS-values to be reliable where they are at least twice as large as the standard deviation (CV ≤ 0.5). Unreliable ΔCFS-values are found near the causative fault and between lobes of positive and negative stress change, where a small change in fault strike causes ΔCFS-values to change sign. The most reliable ΔCFS-values are found away from the source fault in the middle of positive and negative ΔCFS-lobes, a likely general pattern. Using the reliability criterion, our results support the static stress-triggering hypothesis. Nevertheless, our analysis also suggests that results from previous stress-triggering studies not considering source model uncertainties may have lead to a biased interpretation of the importance of static stress-triggering.

  6. Reliability, validity and sensitivity to change of neurogenic bowel dysfunction score in patients with spinal cord injury

    DEFF Research Database (Denmark)

    Erdem, D.; Hava, D.; Keskinoglu, P.

    2017-01-01

    cord injury (SCI). The reliability of NBD score was assessed by test-retest reliability and internal consistency. Cronbach's alpha coefficient was calculated to determine internal consistency. The construct validity was evaluated by exploring correlations between the NBD score and SF-36 scales, patient...... assessment of impact of NBD on quality of life (QoL) and the physician global assessment (PGA). The Global Rating of Change (GRC) scale was used to assess the change of NBD to investigate the sensitivity of the score to change. Results: Cronbach's alpha coefficient was 0.547. In test-retest reliability...

  7. Assessment of reliability, validity, responsiveness and minimally important change of the German Hip dysfunction and osteoarthritis outcome score (HOOS) in patients with osteoarthritis of the hip.

    Science.gov (United States)

    Arbab, Dariusch; van Ochten, Johannes H M; Schnurr, Christoph; Bouillon, Bertil; König, Dietmar

    2017-12-01

    Patient-reported outcome measures are a critical tool in evaluating the efficacy of orthopedic procedures. The intention of this study was to evaluate reliability, validity, responsiveness and minimally important change of the German version of the Hip dysfunction and osteoarthritis outcome score (HOOS). The German HOOS was investigated in 251 consecutive patients before and 6 months after total hip arthroplasty. All patients completed HOOS, Oxford-Hip Score, Short-Form (SF-36) and numeric scales for pain and disability. Test-retest reliability, internal consistency, floor and ceiling effects, construct validity and minimal important change were analyzed. The German HOOS demonstrated excellent test-retest reliability with intraclass correlation coefficient values > 0.7. Cronbach´s alpha values demonstrated strong internal consistency. As hypothesized, HOOS subscales strongly correlated with corresponding OHS and SF-36 domains. All subscales showed excellent (effect size/standardized response means > 0.8) responsiveness between preoperative assessment and postoperative follow-up. The HOOS and all subdomains showed higher changes than the minimal detectable change which indicates true changes. The German version of the HOOS demonstrated good psychometric properties. It proved to be valid, reliable and responsive to the changes instrument for use in patients with hip osteoarthritis undergoing total hip replacement.

  8. Comparison of reliability of five patellar position indices at various stifle joint angles in pelvic limbs obtained from cadavers of red foxes (Vulpes vulpes)

    DEFF Research Database (Denmark)

    Miles, James E; Nielsen, Dorte H; Jensen, Bente Rona

    2012-01-01

    To compare 5 patellar position indices at various stifle joint angles in cadavers of red foxes, determine measurement reliability, and assess the suitability of these indices for clinical use.......To compare 5 patellar position indices at various stifle joint angles in cadavers of red foxes, determine measurement reliability, and assess the suitability of these indices for clinical use....

  9. Time-dependent reliability sensitivity analysis of motion mechanisms

    International Nuclear Information System (INIS)

    Wei, Pengfei; Song, Jingwen; Lu, Zhenzhou; Yue, Zhufeng

    2016-01-01

    Reliability sensitivity analysis aims at identifying the source of structure/mechanism failure, and quantifying the effects of each random source or their distribution parameters on failure probability or reliability. In this paper, the time-dependent parametric reliability sensitivity (PRS) analysis as well as the global reliability sensitivity (GRS) analysis is introduced for the motion mechanisms. The PRS indices are defined as the partial derivatives of the time-dependent reliability w.r.t. the distribution parameters of each random input variable, and they quantify the effect of the small change of each distribution parameter on the time-dependent reliability. The GRS indices are defined for quantifying the individual, interaction and total contributions of the uncertainty in each random input variable to the time-dependent reliability. The envelope function method combined with the first order approximation of the motion error function is introduced for efficiently estimating the time-dependent PRS and GRS indices. Both the time-dependent PRS and GRS analysis techniques can be especially useful for reliability-based design. This significance of the proposed methods as well as the effectiveness of the envelope function method for estimating the time-dependent PRS and GRS indices are demonstrated with a four-bar mechanism and a car rack-and-pinion steering linkage. - Highlights: • Time-dependent parametric reliability sensitivity analysis is presented. • Time-dependent global reliability sensitivity analysis is presented for mechanisms. • The proposed method is especially useful for enhancing the kinematic reliability. • An envelope method is introduced for efficiently implementing the proposed methods. • The proposed method is demonstrated by two real planar mechanisms.

  10. Prediction of software operational reliability using testing environment factors

    International Nuclear Information System (INIS)

    Jung, Hoan Sung; Seong, Poong Hyun

    1995-01-01

    A number of software reliability models have been developed to estimate and to predict software reliability. However, there are no established standard models to quantify software reliability. Most models estimate the quality of software in reliability figures such as remaining faults, failure rate, or mean time to next failure at the testing phase, and they consider them ultimate indicators of software reliability. Experience shows that there is a large gap between predicted reliability during development and reliability measured during operation, which means that predicted reliability, or so-called test reliability, is not operational reliability. Customers prefer operational reliability to test reliability. In this study, we propose a method that predicts operational reliability rather than test reliability by introducing the testing environment factor that quantifies the changes in environments

  11. Establishing reliable cognitive change in children with epilepsy: The procedures and results for a sample with epilepsy

    NARCIS (Netherlands)

    van Iterson, L.; Augustijn, P.B.; de Jong, P.F.; van der Leij, A.

    2013-01-01

    The goal of this study was to investigate reliable cognitive change in epilepsy by developing computational procedures to determine reliable change index scores (RCIs) for the Dutch Wechsler Intelligence Scales for Children. First, RCIs were calculated based on stability coefficients from a

  12. Vulnerability of Agriculture to Climate Change as Revealed by Relationships between Simulated Crop Yield and Climate Change Indices

    Science.gov (United States)

    King, A. W.; Absar, S. M.; Nair, S.; Preston, B. L.

    2012-12-01

    vulnerability analysis. They also contribute to considerations of adaptation, focusing attention on adapting to increased variability in yield rather than just reductions in yield. For example, in the face of increased variability or reduced reliability, hedging and risk spreading strategies may be more important than technological innovations such as drought-resistant crops or other optimization strategies. Our findings also have implications for the choice and application of climate extreme indices, demands on models used to project climate change and the development of next generation integrated assessment models (IAM) that incorporate the agricultural sector, and especially adaption within that sector, in energy and broader more general markets.

  13. Improving the reliability of fishery predictions under climate change

    DEFF Research Database (Denmark)

    Brander, Keith

    2015-01-01

    The increasing number of publications assessing impacts of climate change on marine ecosystems and fisheries attests to rising scientific and public interest. A selection of recent papers, dealing more with biological than social and economic aspects, is reviewed here, with particular attention...... to the reliability of projections of climate impacts on future fishery yields. The 2014 Intergovernmental Panel on Climate Change (IPCC) report expresses high confidence in projections that mid- and high-latitude fish catch potential will increase by 2050 and medium confidence that low-latitude catch potential...... understanding of climate impacts, such as how to improve coupled models from physics to fish and how to strengthen confidence in analysis of time series...

  14. Assessing Changes in the Reliability of the U.S. Electric Power System

    Energy Technology Data Exchange (ETDEWEB)

    Larsen, Peter H. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Stanford Univ., CA (United States). Dept. of Physics; LaCommare, Kristina H. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Eto, Joseph H. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Sweeney, James L. [Stanford Univ., CA (United States)

    2015-08-01

    Over the past 15 years, the most well-publicized efforts to assess trends in U.S. electric power system reliability have focused only on a subset of all power interruption events (see, for example, Amin 2008 and Campbell 2012)—namely, only the very largest events, which trigger immediate emergency reporting to federal agencies and industry regulators. Anecdotally, these events are thought by many to represent no more than 10% of the power interruptions experienced annually by electricity consumers. Moreover, a review of these emergency reports has identified shortcomings in relying on these data as reliable sources for assessing trends, even with the reliability events they report (Fisher et al. 2012). Recent work has begun to address these limitations by examining trends in reliability data collected annually by electricity distribution companies (Eto et al. 2012). In principle, all power interruptions experienced by electricity customers, regardless of size, are recorded by the distribution utility. Moreover, distribution utilities have a long history of recording this information, often in response to mandates from state public utility commissions (Eto et al. 2006). Thus, studies that rely on reliability data collected by distribution utilities can, in principle, provide a more complete basis upon which to assess trends or changes in reliability over time.

  15. Validation of Land Cover Products Using Reliability Evaluation Methods

    Directory of Open Access Journals (Sweden)

    Wenzhong Shi

    2015-06-01

    Full Text Available Validation of land cover products is a fundamental task prior to data applications. Current validation schemes and methods are, however, suited only for assessing classification accuracy and disregard the reliability of land cover products. The reliability evaluation of land cover products should be undertaken to provide reliable land cover information. In addition, the lack of high-quality reference data often constrains validation and affects the reliability results of land cover products. This study proposes a validation schema to evaluate the reliability of land cover products, including two methods, namely, result reliability evaluation and process reliability evaluation. Result reliability evaluation computes the reliability of land cover products using seven reliability indicators. Process reliability evaluation analyzes the reliability propagation in the data production process to obtain the reliability of land cover products. Fuzzy fault tree analysis is introduced and improved in the reliability analysis of a data production process. Research results show that the proposed reliability evaluation scheme is reasonable and can be applied to validate land cover products. Through the analysis of the seven indicators of result reliability evaluation, more information on land cover can be obtained for strategic decision-making and planning, compared with traditional accuracy assessment methods. Process reliability evaluation without the need for reference data can facilitate the validation and reflect the change trends of reliabilities to some extent.

  16. Establishing Reliable Cognitive Change in Children with Epilepsy: The Procedures and Results for a Sample with Epilepsy

    Science.gov (United States)

    van Iterson, Loretta; Augustijn, Paul B.; de Jong, Peter F.; van der Leij, Aryan

    2013-01-01

    The goal of this study was to investigate reliable cognitive change in epilepsy by developing computational procedures to determine reliable change index scores (RCIs) for the Dutch Wechsler Intelligence Scales for Children. First, RCIs were calculated based on stability coefficients from a reference sample. Then, these RCIs were applied to a…

  17. Evidence-Based Indicators of Neuropsychological Change in the Individual Patient: Relevant Concepts and Methods

    Science.gov (United States)

    Duff, Kevin

    2012-01-01

    Repeated assessments are a relatively common occurrence in clinical neuropsychology. The current paper will review some of the relevant concepts (e.g., reliability, practice effects, alternate forms) and methods (e.g., reliable change index, standardized based regression) that are used in repeated neuropsychological evaluations. The focus will be on the understanding and application of these concepts and methods in the evaluation of the individual patient through examples. Finally, some future directions for assessing change will be described. PMID:22382384

  18. RTE - Reliability report 2016

    International Nuclear Information System (INIS)

    2017-06-01

    Every year, RTE produces a reliability report for the past year. This document lays out the main factors that affected the electrical power system's operational reliability in 2016 and the initiatives currently under way intended to ensure its reliability in the future. Within a context of the energy transition, changes to the European interconnected network mean that RTE has to adapt on an on-going basis. These changes include the increase in the share of renewables injecting an intermittent power supply into networks, resulting in a need for flexibility, and a diversification in the numbers of stakeholders operating in the energy sector and changes in the ways in which they behave. These changes are dramatically changing the structure of the power system of tomorrow and the way in which it will operate - particularly the way in which voltage and frequency are controlled, as well as the distribution of flows, the power system's stability, the level of reserves needed to ensure supply-demand balance, network studies, assets' operating and control rules, the tools used and the expertise of operators. The results obtained in 2016 are evidence of a globally satisfactory level of reliability for RTE's operations in somewhat demanding circumstances: more complex supply-demand balance management, cross-border schedules at interconnections indicating operation that is closer to its limits and - most noteworthy - having to manage a cold spell just as several nuclear power plants had been shut down. In a drive to keep pace with the changes expected to occur in these circumstances, RTE implemented numerous initiatives to ensure high levels of reliability: - maintaining investment levels of euro 1.5 billion per year; - increasing cross-zonal capacity at borders with our neighbouring countries, thus bolstering the security of our electricity supply; - implementing new mechanisms (demand response, capacity mechanism, interruptibility, etc.); - involvement in tests or projects

  19. Multi-station basis for Polar Cap (PC) indices: ensuring credibility and operational reliability

    Science.gov (United States)

    Stauning, Peter

    2018-02-01

    The Polar Cap (PC) indices, PCN (North) and PCS (South) are based on polar geomagnetic observations from Qaanaaq (Thule) and Vostok, respectively, processed to measure the transpolar plasma convection that may seriously affect space weather conditions. To establish reliable space weather forecasts based on PC indices, and also to ensure credibility of their use for scientific analyses of solar wind-magnetosphere interactions, additional sources of data for the PC indices are investigated. In the search for alternative index sources, objective quality criteria are established here to be used for the selection among potential candidates. These criteria are applied to existing PC index series to establish a quality scale. In the Canadian region, the data from Resolute Bay magnetometer are shown to provide alternative PCN indices of adequate quality. In Antarctica, the data from Concordia Dome-C observatory are shown to provide basis for alternative PCS indices. In examples to document the usefulness of these alternative index sources it is shown that PCN indices in a real-time version based on magnetometer data from Resolute Bay could have given 6 h of early warning, of which the last 2 h were "red alert", up to the onset of the strong substorm event on 13 March 1989 that caused power outage in Quebec. The alternative PCS indices based on data from Dome-C have helped to disclose that presently available Vostok-based PCS index values are corrupted throughout most of 2011.

  20. Incorporating Cyber Layer Failures in Composite Power System Reliability Evaluations

    Directory of Open Access Journals (Sweden)

    Yuqi Han

    2015-08-01

    Full Text Available This paper proposes a novel approach to analyze the impacts of cyber layer failures (i.e., protection failures and monitoring failures on the reliability evaluation of composite power systems. The reliability and availability of the cyber layer and its protection and monitoring functions with various topologies are derived based on a reliability block diagram method. The availability of the physical layer components are modified via a multi-state Markov chain model, in which the component protection and monitoring strategies, as well as the cyber layer topology, are simultaneously considered. Reliability indices of composite power systems are calculated through non-sequential Monte-Carlo simulation. Case studies demonstrate that operational reliability downgrades in cyber layer function failure situations. Moreover, protection function failures have more significant impact on the downgraded reliability than monitoring function failures do, and the reliability indices are especially sensitive to the change of the cyber layer function availability in the range from 0.95 to 1.

  1. Reliability and sensitivity to change of the timed standing balance test in children with down syndrome

    Directory of Open Access Journals (Sweden)

    Vencita Priyanka Aranha

    2016-01-01

    Full Text Available Objective: To estimate the reliability and sensitivity to change of the timed standing balance test in children with Down syndrome (DS. Methods: It was a nonblinded, comparison study with a convenience sample of subjects consisting of children with DS (n = 9 aged 8–17 years. The main outcome measure was standing balance which was assessed using timed standing balance test, the time required to maintain in four conditions, eyes open static, eyes closed static, eyes open dynamic, and eyes closed dynamic. Results: Relative reliability was excellent for all four conditions with an Interclass Correlation Coefficient (ICC ranging from 0.91 to 0.93. The variation between repeated measurements for each condition was minimal with standard error of measurement (SEM of 0.21–0.59 s, suggestive of excellent absolute reliability. The sensitivity to change as measured by smallest real change (SRC was 1.27 s for eyes open static, 1.63 s for eyes closed static, 0.58 s for eyes open dynamic, and 0.61 s for eyes closed static. Conclusions: Timed standing balance test is an easy to administer test and sensitive to change with strong absolute and relative reliabilities, an important first step in establishing its utility as a clinical balance measure in children with DS.

  2. Measuring disability: a systematic review of the validity and reliability of the Global Activity Limitations Indicator (GALI).

    Science.gov (United States)

    Van Oyen, Herman; Bogaert, Petronille; Yokota, Renata T C; Berger, Nicolas

    2018-01-01

    GALI or Global Activity Limitation Indicator is a global survey instrument measuring participation restriction. GALI is the measure underlying the European indicator Healthy Life Years (HLY). Gali has a substantial policy use within the EU and its Member States. The objective of current paper is to bring together what is known from published manuscripts on the validity and the reliability of GALI. Following the PRISMA guidelines, two search strategies (PUBMED, Google Scholar) were combined to identify manuscripts published in English with publication date 2000 or beyond. Articles were classified as reliability studies, concurrent or predictive validity studies, in national or international populations. Four cross-sectional studies (of which 2 international) studied how GALI relates to other health measures (concurrent validity). A dose-response effect by GALI severity level on the association with the other health status measures was observed in the national studies. The 2 international studies (SHARE, EHIS) concluded that the odds of reporting participation restriction was higher in subjects with self-reported or observed functional limitations. In SHARE, the size of the Odds Ratio's (ORs) in the different countries was homogeneous, while in EHIS the size of the ORs varied more strongly. For the predictive validity, subjects were followed over time (4 studies of which one international). GALI proved, both in national and international data, to be a consistent predictor of future health outcomes both in terms of mortality and health care expenditure. As predictors of mortality, the two distinct health concepts, self-rated health and GALI, acted independently and complementary of each other. The one reliability study identified reported a sufficient reliability of GALI. GALI as inclusive one question instrument fits all conceptual characteristics specified for a global measure on participation restriction. In none of the studies, included in the review, there was

  3. Neither self-reported ethnicity nor declared family origin are reliable indicators of genomic ancestry.

    Science.gov (United States)

    Ramos, Bruna Ribeiro de Andrade; D'Elia, Maria Paula Barbieri; Amador, Marcos Antônio Trindade; Santos, Ney Pereira Carneiro; Santos, Sidney Emanuel Batista; da Cruz Castelli, Erick; Witkin, Steven S; Miot, Hélio Amante; Miot, Luciane Donida Bartoli; da Silva, Márcia Guimarães

    2016-06-01

    Ancestry information can be useful in investigations of diseases with a genetic or infectious background. As the Brazilian population is highly admixed physical traits tend to be poor indicators of ancestry. The assessment of ancestry by ancestry informative markers (AIMs) can exclude the subjectivity of self-declared ethnicity and reported family origin. We aimed to evaluate the reliability of self-reported ethnicity or reported family origin as indicators of genomic ancestry in a female population from the Southeast of Brazil. Two cohorts were included: 404 women asked to self-report their ethnicity (Pop1) and 234 women asked to report their family's origin (Pop2). Identification of AIMs was performed using a panel of 61 markers and results were plotted against parental populations-Amerindian, Western European and Sub-Saharan African-using Structure v2.3.4. In Pop1 57.4 % of women self-reported as white, 34.6 % as brown and 8.0 % as black. Median global European, Amerindian and African contributions were 66.8, 12.6 and 16.6 %. In Pop2, 66.4 % of women declared European origin, 23.9 % African origin and 26.9 % Amerindian. Median global European, Amerindian and African contributions were 80.8, 7.3 and 7.6 %, respectively. Only 31.0 and 21.0 % of the global variation in African and European contributions, respectively, could be explained by self-reported ethnicity and reported family origin only accounted for 20.0 and 5.0 % of the variations observed in African and European ancestries, respectively. Amerindian ancestry did not influence self-reported ethnicity or declared family origin. Neither self-reported ethnicity nor declared family origin are reliable indicators of genomic ancestry in these Brazilian populations.

  4. Reliability, validity and minimal detectable change of the Mini-BESTest in Greek participants with chronic stroke.

    Science.gov (United States)

    Lampropoulou, Sofia I; Billis, Evdokia; Gedikoglou, Ingrid A; Michailidou, Christina; Nowicky, Alexander V; Skrinou, Dimitra; Michailidi, Fotini; Chandrinou, Danae; Meligkoni, Margarita

    2018-02-23

    This study aimed to investigate the psychometric characteristics of reliability, validity and ability to detect change of a newly developed balance assessment tool, the Mini-BESTest, in Greek patients with stroke. A prospective, observational design study with test-retest measures was conducted. A convenience sample of 21 Greek patients with chronic stroke (14 male, 7 female; age of 63 ± 16 years) was recruited. Two independent examiners administered the scale, for the inter-rater reliability, twice within 10 days for the test-retest reliability. Bland Altman Analysis for repeated measures assessed the absolute reliability and the Standard Error of Measurement (SEM) and the Minimum Detectable Change at 95% confidence interval (MDC 95% ) were established. The Greek Mini-BESTest (Mini-BESTest GR ) was correlated with the Greek Berg Balance Scale (BBS GR ) for assessing the concurrent validity and with the Timed Up and Go (TUG), the Functional Reach Test (FRT) and the Greek Falls Efficacy Scale-International (FES-I GR ) for the convergent validity. The Mini-BESTestGR demonstrated excellent inter-rater reliability (ICC (95%CI) = 0.997 (0.995-0.999, SEM = 0.46) with the scores of two raters within the limits of agreement (mean dif  = -0.143 ± 0.727, p > 0.05) and test-retest reliability (ICC (95%CI) = 0.966 (0.926-0.988), SEM = 1.53). Additionally, the Mini-BESTest GR yielded very strong to moderate correlations with BBS GR (r = 0.924, p reliability and the equally good validity of the Mini-BESTest GR , strongly support its utility in Greek people with chronic stroke. Its ability to identify clinically meaningful changes and falls risk need further investigation.

  5. Test-retest reliability and minimal detectable change of two simplified 3-point balance measures in patients with stroke.

    Science.gov (United States)

    Chen, Yi-Miau; Huang, Yi-Jing; Huang, Chien-Yu; Lin, Gong-Hong; Liaw, Lih-Jiun; Lee, Shih-Chieh; Hsieh, Ching-Lin

    2017-10-01

    The 3-point Berg Balance Scale (BBS-3P) and 3-point Postural Assessment Scale for Stroke Patients (PASS-3P) were simplified from the BBS and PASS to overcome the complex scoring systems. The BBS-3P and PASS-3P were more feasible in busy clinical practice and showed similarly sound validity and responsiveness to the original measures. However, the reliability of the BBS-3P and PASS-3P is unknown limiting their utility and the interpretability of scores. We aimed to examine the test-retest reliability and minimal detectable change (MDC) of the BBS-3P and PASS-3P in patients with stroke. Cross-sectional study. The rehabilitation departments of a medical center and a community hospital. A total of 51 chronic stroke patients (64.7% male). Both balance measures were administered twice 7 days apart. The test-retest reliability of both the BBS-3P and PASS-3P were examined by intraclass correlation coefficients (ICC). The MDC and its percentage over the total score (MDC%) of each measure was calculated for examining the random measurement errors. The ICC values of the BBS-3P and PASS-3P were 0.99 and 0.97, respectively. The MDC% (MDC) of the BBS-3P and PASS-3P were 9.1% (5.1 points) and 8.4% (3.0 points), respectively, indicating that both measures had small and acceptable random measurement errors. Our results showed that both the BBS-3P and the PASS-3P had good test-retest reliability, with small and acceptable random measurement error. These two simplified 3-level balance measures can provide reliable results over time. Our findings support the repeated administration of the BBS-3P and PASS-3P to monitor the balance of patients with stroke. The MDC values can help clinicians and researchers interpret the change scores more precisely.

  6. The reliability, minimal detectable change and concurrent validity of a gravity-based bubble inclinometer and iphone application for measuring standing lumbar lordosis.

    Science.gov (United States)

    Salamh, Paul A; Kolber, Morey

    2014-01-01

    To investigate the reliability, minimal detectable change (MDC90) and concurrent validity of a gravity-based bubble inclinometer (inclinometer) and iPhone® application for measuring standing lumbar lordosis. Two investigators used both an inclinometer and an iPhone® with an inclinometer application to measure lumbar lordosis of 30 asymptomatic participants. ICC models 3,k and 2,k were used for the intrarater and interrater analysis, respectively. Good interrater and intrarater reliability was present for the inclinometer with Intraclass Correlation Coefficients (ICC) of 0.90 and 0.85, respectively and the iPhone® application with ICC values of 0.96 and 0.81. The minimal detectable change (MDC90) indicates that a change greater than or equal to 7° and 6° is needed to exceed the threshold of error using the iPhone® and inclinometer, respectively. The concurrent validity between the two instruments was good with a Pearson product-moment coefficient of correlation (r) of 0.86 for both raters. Ninety-five percent limits of agreement identified differences ranging from 9° greater in regards to the iPhone® to 8° less regarding the inclinometer. Both the inclinometer and iPhone® application possess good interrater reliability, intrarater reliability and concurrent validity for measuring standing lumbar lordosis. This investigation provides preliminary evidence to suggest that smart phone applications may offer clinical utility comparable to inclinometry for quantifying standing lumbar lordosis. Clinicians should recognize potential individual differences when using these devices interchangeably.

  7. Reliability of mandibular canines as indicators for sexual dichotomy.

    Science.gov (United States)

    Hosmani, Jagadish V; Nayak, Ramakant S; Kotrashetti, Vijayalakshmi S; S, Pradeep; Babji, Deepa

    2013-02-01

    Amongst the various calcified structures in the human body, teeth have gained lot of popularity in estimating the sex of an individual as they are highly resistant to destruction and decomposition. Using permanent mandibular canines many researchers have predicted a high level of accuracy in identifying the sex correctly. The purpose of our study was to gauge the effectiveness of mandibular canines in discerning sex. Fifty dental casts each of males and females were utilized for the study. Mesio-distal dimension and inter-canine distance of mandibular right and left canine was recorded using digital vernier caliper and mandibular canine index was calculated. The mean value of mesio-distal dimensions of right and left mandibular canine was slightly greater in males compared to females. The mandibular canine index was equal in both sexes. Inter-canine distance was marginally higher in males compared to females. Despite of higher values in males none of the parameters were statistically significant. The results herein bolster contemporary studies that mesio-distal dimensions of mandibular canines and mandibular canine index do not reflect sexual dimorphism and that its application should be discontinued in sex prediction among Indian populations. How to cite this article: Hosmani J V, Nayak R S, Kotrashetti V S, Pradeep S, Babji D. Reliability of Mandibular Canines as Indicators for Sexual Dichotomy. J Int Oral Health 2013; 5(1):1-7.

  8. The changing Chinese SEA indicator guidelines

    DEFF Research Database (Denmark)

    Gao, Jingjing; Christensen, Per; Kørnøv, Lone

    2014-01-01

    general trends in the development of SEA and other environmental policies in a recent, Chinese context. Beside a more top-down, intentional approach specifying indicators for different sectors based on Chinese experiences from the preceding years, another significant change, following the new guidelines...

  9. Frontiers of reliability

    CERN Document Server

    Basu, Asit P; Basu, Sujit K

    1998-01-01

    This volume presents recent results in reliability theory by leading experts in the world. It will prove valuable for researchers, and users of reliability theory. It consists of refereed invited papers on a broad spectrum of topics in reliability. The subjects covered include Bayesian reliability, Bayesian reliability modeling, confounding in a series system, DF tests, Edgeworth approximation to reliability, estimation under random censoring, fault tree reduction for reliability, inference about changes in hazard rates, information theory and reliability, mixture experiment, mixture of Weibul

  10. Communicating global climate change using simple indices: an update

    Energy Technology Data Exchange (ETDEWEB)

    Drost, Frank; Karoly, David [University of Melbourne, School of Earth Sciences, Melbourne, VIC (Australia); Braganza, Karl [National Climate Centre, Bureau of Meteorology, Melbourne, VIC (Australia)

    2012-08-15

    Previous studies have shown that there are several indices of global-scale temperature variations, in addition to global-mean surface air temperature, that are useful for distinguishing natural internal climate variations from anthropogenic climate change. Appropriately defined, such indices have the ability to capture spatio-temporal information in a similar manner to optimal fingerprints of climate change. These indices include the contrast between the average temperatures over land and over oceans, the Northern Hemisphere meridional temperature gradient, the temperature contrast between the Northern and Southern Hemisphere and the magnitude of the annual cycle of average temperatures over land. They contain information independent of the global-mean temperature for internal climate variations at decadal time scales and represent different aspects of the climate system, yet they show common responses to anthropogenic climate change. In addition, the ratio of average temperature changes over land to those over the oceans should be nearly constant for transient climate change. Hence, supplementing analysis of global-mean surface temperature with analyses of these indices can strengthen results of attribution studies of causes of observed climate variations. In this study, we extend the previous work by including the last 10 years of observational data and the CMIP3 climate model simulations analysed for the IPCC AR4. We show that observed changes in these indices over the last 10 years provide increased evidence of an anthropogenic influence on climate. We also show the usefulness of these indices for evaluating the performance of climate models in simulating large-scale variability of surface temperature. (orig.)

  11. Follow-up of CT-derived airway wall thickness: Correcting for changes in inspiration level improves reliability

    Energy Technology Data Exchange (ETDEWEB)

    Pompe, Esther, E-mail: e.pompe@umcutrecht.nl [Department of Respiratory Medicine, University Medical Center Utrecht, Utrecht (Netherlands); Rikxoort, Eva M. van [Department of Radiology, Radboud University Medical Center, Nijmegen (Netherlands); Mets, Onno M. [Department of Radiology, University Medical Center Utrecht, Utrecht (Netherlands); Charbonnier, Jean-Paul [Department of Radiology, Radboud University Medical Center, Nijmegen (Netherlands); Kuhnigk, Jan-Martin [Institute for Medical Image Computing, Fraunhofer MEVIS, Bremen (Germany); Koning, Harry J. de [Department of Public Health, Erasmus Medical Center, Rotterdam (Netherlands); Oudkerk, Matthijs [University of Groningen, University Medical Center Groningen, Groningen, Department of Radiology (Netherlands); Vliegenthart, Rozemarijn [University of Groningen, University Medical Center Groningen, Groningen, Department of Radiology (Netherlands); University of Groningen, University Medical Center Groningen, Center for Medical Imaging-North East Netherlands, Groningen (Netherlands); Zanen, Pieter; Lammers, Jan-Willem J. [Department of Respiratory Medicine, University Medical Center Utrecht, Utrecht (Netherlands); Ginneken, Bram van [Department of Radiology, Radboud University Medical Center, Nijmegen (Netherlands); Jong, Pim A. de; Mohamed Hoesein, Firdaus A.A. [Department of Radiology, University Medical Center Utrecht, Utrecht (Netherlands)

    2016-11-15

    Objectives: Airway wall thickness (AWT) is affected by changes in lung volume. This study evaluated whether correcting AWT on computed tomography (CT) for differences in inspiration level improves measurement agreement, reliability, and power to detect changes over time. Methods: Participants of the Dutch-Belgian lung cancer screening trial who underwent 3-month repeat CT for an indeterminate pulmonary nodule were included. AWT on CT was calculated by the square root of the wall area at a theoretical airway with an internal perimeter of 10 mm (Pi10). The scan with the highest lung volume was labelled as the reference scan and the scan with the lowest lung volume was labelled as the comparison scan. Pi10 derived from the comparison scan was corrected by multiplying it with the ratio of CT lung volume of the comparison scan to CT lung volume on the reference scan. Agreement of uncorrected and corrected Pi10 was studied with the Bland-Altman method, reliability with intra-class correlation coefficients (ICC), and power to detect changes over time was calculated. Results: 315 male participants were included. Limit of agreement and reliability for Pi10 was −0.61 to 0.57 mm (ICC = 0.87), which improved to −0.38 to 0.37 mm (ICC = 0.94) after correction for inspiration level. To detect a 15% change over 3 months, 71 subjects are needed for Pi10 and 26 subjects for Pi10 adjusted for inspiration level. Conclusions: Correcting Pi10 for differences in inspiration level improves reliability, agreement, and power to detect changes over time.

  12. INTER-RATER RELIABILITY FOR MOVEMENT PATTERN ANALYSIS (MPA: MEASURING PATTERNING OF BEHAVIORS VERSUS DISCRETE BEHAVIOR COUNTS AS INDICATORS OF DECISION-MAKING STYLE

    Directory of Open Access Journals (Sweden)

    Brenda L Connors

    2014-06-01

    Full Text Available The unique yield of collecting observational data on human movement has received increasing attention in a number of domains, including the study of decision-making style. As such, interest has grown in the nuances of core methodological issues, including the best ways of assessing inter-rater reliability. In this paper we focus on one key topic – the distinction between establishing reliability for the patterning of behaviors as opposed to the computation of raw counts – and suggest that reliability for each be compared empirically rather than determined a priori. We illustrate by assessing inter-rater reliability for key outcome measures derived from Movement Pattern Analysis (MPA, an observational methodology that records body movements as indicators of decision-making style with demonstrated predictive validity. While reliability ranged from moderate to good for raw counts of behaviors reflecting each of two Overall Factors generated within MPA (Assertion and Perspective, inter-rater reliability for patterning (proportional indicators of each factor was significantly higher and excellent (ICC = .89. Furthermore, patterning, as compared to raw counts, provided better prediction of observable decision-making process assessed in the laboratory. These analyses support the utility of using an empirical approach to inform the consideration of measuring discrete behavioral counts versus patterning of behaviors when determining inter-rater reliability of observable behavior. They also speak to the substantial reliability that may be achieved via application of theoretically grounded observational systems such as MPA that reveal thinking and action motivations via visible movement patterns.

  13. The effect of a graphical interpretation of a statistic trend indicator (Trigg's Tracking Variable) on the detection of simulated changes.

    Science.gov (United States)

    Kennedy, R R; Merry, A F

    2011-09-01

    Anaesthesia involves processing large amounts of information over time. One task of the anaesthetist is to detect substantive changes in physiological variables promptly and reliably. It has been previously demonstrated that a graphical trend display of historical data leads to more rapid detection of such changes. We examined the effect of a graphical indication of the magnitude of Trigg's Tracking Variable, a simple statistically based trend detection algorithm, on the accuracy and latency of the detection of changes in a micro-simulation. Ten anaesthetists each viewed 20 simulations with four variables displayed as the current value with a simple graphical trend display. Values for these variables were generated by a computer model, and updated every second; after a period of stability a change occurred to a new random value at least 10 units from baseline. In 50% of the simulations an indication of the rate of change was given by a five level graphical representation of the value of Trigg's Tracking Variable. Participants were asked to indicate when they thought a change was occurring. Changes were detected 10.9% faster with the trend indicator present (mean 13.1 [SD 3.1] cycles vs 14.6 [SD 3.4] cycles, 95% confidence interval 0.4 to 2.5 cycles, P = 0.013. There was no difference in accuracy of detection (median with trend detection 97% [interquartile range 95 to 100%], without trend detection 100% [98 to 100%]), P = 0.8. We conclude that simple statistical trend detection may speed detection of changes during routine anaesthesia, even when a graphical trend display is present.

  14. Reliability and validity of the Tilburg Frailty Indicator (TFI) among Chinese community-dwelling older people.

    Science.gov (United States)

    Dong, Lijuan; Liu, Na; Tian, Xiaoyu; Qiao, Xiaoxia; Gobbens, Robbert J J; Kane, Robert L; Wang, Cuili

    2017-11-01

    To translate the Tilburg Frailty Indicator (TFI) into Chinese and assess its reliability and validity. A sample of 917 community-dwelling older people, aged ≥60 years, in a Chinese city was included between August 2015 and March 2016. Construct validity was assessed using alternative measures corresponding to the TFI items, including self-rated health status (SRH), unintentional weight loss, walking speed, timed-up-and-go tests (TUGT), making telephone calls, grip strength, exhaustion, Short Portable Mental Status Questionnaire (SPMSQ), Geriatric Depression scale (GDS-15), emotional role, Adaptability Partnership Growth Affection and Resolve scale (APGAR) and Social Support Rating Scale (SSRS). Fried's phenotype and frailty index were measured to evaluate criterion validity. Adverse health outcomes (ADL and IADL disability, healthcare utilization, GDS-15, SSRS) were used to assess predictive (concurrent) validity. The internal consistency reliability was good (Cronbach's α=0.71). The test-retest reliability was strong (r=0.88). Kappa coefficients showed agreements between the TFI items and corresponding alternative measures. Alternative measures correlated as expected with the three domains of TFI, with an exclusion that alternative psychological measures had similar correlations with psychological and physical domains of the TFI. The Chinese TFI had excellent criterion validity with the AUCs regarding physical phenotype and frailty index of 0.87 and 0.86, respectively. The predictive (concurrent) validities of the adverse health outcomes and healthcare utilization were acceptable (AUCs: 0.65-0.83). The Chinese TFI has good validity and reliability as an integral instrument to measure frailty of older people living in the community in China. Copyright © 2017 Elsevier B.V. All rights reserved.

  15. Regionalisation of Hydrological Indices to Assess Land-Use Change Impacts in the Tropical Andes

    Science.gov (United States)

    Buytaert, W.; Ochoa Tocachi, B. F.

    2014-12-01

    Andean ecosystems are major water sources for cities and communities located in the Tropical Andes; however, there is a considerable lack of knowledge about their hydrology. Two problems are especially important: (i) the lack of monitoring to assess the impacts of historical land-use and cover change and degradation (LUCCD) at catchment scale, and (ii) the high variability in climatic and hydrological conditions that complicate the evaluation of land management practices. This study analyses how a reliable LUCCD impacts assessment can be performed in an environment of high variability combined with data-scarcity and low-quality records. We use data from participatory hydrological monitoring activities in 20 catchments distributed along the tropical Andes. A set of 46 hydrological indices is calculated and regionalized by relating them to 42 physical catchment properties. Principal Component Analysis (PCA) is performed to maximise available data while minimising redundancy in the sets of variables. Hydrological model parameters are constrained by estimated indices, and different behavioural predictions are assembled to provide a generalised response on which we assess LUCCD impacts. Results from this methodology show that the attributed effects of LUCCD in pair-wise catchment comparisons may be overstated or hidden by different sources of uncertainty, including measurement inaccuracies and model structural errors. We propose extrapolation and evaluation in ungauged catchments as a way to regionalize LUCCD predictions and to provide statistically significant conclusions in the Andean region. These estimations may deliver reliable knowledge to evaluate the hydrological impact of different watershed management practices.

  16. Effect of Climate Change on Reliability of Rainwater Harvesting Systems for Kabarole District, Uganda

    Directory of Open Access Journals (Sweden)

    Violet Kisakye

    2018-01-01

    Full Text Available This paper assesses the effect of climate change on reliability of rainwater harvesting systems for Kabarole district, Uganda, as predicted by 6 best performing global circulation models (GCMs. A daily water balance model was used to simulate the performance of a rainwater harvesting system using historical daily rainfall data for 20 years. The GCMs used to generate daily rainfall projections for 2025–2055 and 2060–2090 periods included; ACCESS1-0, BCC-CSM-1-M, CNRM-CM5, HADGEM2-CC, HADGEM2-ES and MIROC5. Analysis was based on the Ugandan weather seasons which included March, April, May (MAM and September, October, November (SON rain seasons in addition to December, January, February (DJF and June, July, August (JJA dry seasons. While an increase in reliability is predicted for the SON season, the worst-case scenario is projected during the MAM season with a reliability reduction of over 40% for the 2055–2090 period. This corresponds to a 27% reduction in water security for the same period. The DJF season is also expected to experience reduced water security by 1–8% for 2025–2055 and 2060–2090 with a 0.5 m3 tank size. Therefore, some form of extra harvesting surface and increased tank size will be required to maintain 80% systems reliability considering climate change.

  17. How reliable are geometry-based building indices as thermal performance indicators?

    International Nuclear Information System (INIS)

    Rodrigues, Eugénio; Amaral, Ana Rita; Gaspar, Adélio Rodrigues; Gomes, Álvaro

    2015-01-01

    Highlights: • Geometry-based building indices are tested in different European climate regions. • Building design programs are used to randomly generate sets of simulation models. • Some indices correlate in specific climates and design programs. • Shape-based Relative Compactness presented the best correlation of all indices. • Window-to-Surface Ratio was the window-based index with best correlation. - Abstract: Architects and urban planners have been relying on geometry-based indices to design more energy efficient buildings for years. The advantage of such indices is their ease of use and capability to capture the relation of a few geometric variables with the building’s performance. However, such relation is usually found using only a few simple building models and considering only a few climate regions. This paper presents the analysis of six geometry-based building indices to determine their adequacy in eight different climate regions in Europe. For each location, three residential building design programs were used as building specifications. Two algorithms were employed to randomly generate and assess the thermal performance of three sets of 500 alternative building models. The results show that geometry-based indices only correlate with the buildings’ thermal performance according to specific climate regions and building design programs

  18. Reliability Worth Analysis of Distribution Systems Using Cascade Correlation Neural Networks

    DEFF Research Database (Denmark)

    Heidari, Alireza; Agelidis, Vassilios; Pou, Josep

    2018-01-01

    Reliability worth analysis is of great importance in the area of distribution network planning and operation. The reliability worth's precision can be affected greatly by the customer interruption cost model used. The choice of the cost models can change system and load point reliability indices....... In this study, a cascade correlation neural network is adopted to further develop two cost models comprising a probabilistic distribution model and an average or aggregate model. A contingency-based analytical technique is adopted to conduct the reliability worth analysis. Furthermore, the possible effects...

  19. An Introduction To Reliability

    International Nuclear Information System (INIS)

    Park, Kyoung Su

    1993-08-01

    This book introduces reliability with definition of reliability, requirement of reliability, system of life cycle and reliability, reliability and failure rate such as summary, reliability characteristic, chance failure, failure rate which changes over time, failure mode, replacement, reliability in engineering design, reliability test over assumption of failure rate, and drawing of reliability data, prediction of system reliability, conservation of system, failure such as summary and failure relay and analysis of system safety.

  20. Reliability and Validity of a New Test of Change-of-Direction Speed for Field-Based Sports: the Change-of-Direction and Acceleration Test (CODAT).

    Science.gov (United States)

    Lockie, Robert G; Schultz, Adrian B; Callaghan, Samuel J; Jeffriess, Matthew D; Berry, Simon P

    2013-01-01

    Field sport coaches must use reliable and valid tests to assess change-of-direction speed in their athletes. Few tests feature linear sprinting with acute change- of-direction maneuvers. The Change-of-Direction and Acceleration Test (CODAT) was designed to assess field sport change-of-direction speed, and includes a linear 5-meter (m) sprint, 45° and 90° cuts, 3- m sprints to the left and right, and a linear 10-m sprint. This study analyzed the reliability and validity of this test, through comparisons to 20-m sprint (0-5, 0-10, 0-20 m intervals) and Illinois agility run (IAR) performance. Eighteen Australian footballers (age = 23.83 ± 7.04 yrs; height = 1.79 ± 0.06 m; mass = 85.36 ± 13.21 kg) were recruited. Following familiarization, subjects completed the 20-m sprint, CODAT, and IAR in 2 sessions, 48 hours apart. Intra-class correlation coefficients (ICC) assessed relative reliability. Absolute reliability was analyzed through paired samples t-tests (p ≤ 0.05) determining between-session differences. Typical error (TE), coefficient of variation (CV), and differences between the TE and smallest worthwhile change (SWC), also assessed absolute reliability and test usefulness. For the validity analysis, Pearson's correlations (p ≤ 0.05) analyzed between-test relationships. Results showed no between-session differences for any test (p = 0.19-0.86). CODAT time averaged ~6 s, and the ICC and CV equaled 0.84 and 3.0%, respectively. The homogeneous sample of Australian footballers meant that the CODAT's TE (0.19 s) exceeded the usual 0.2 x standard deviation (SD) SWC (0.10 s). However, the CODAT is capable of detecting moderate performance changes (SWC calculated as 0.5 x SD = 0.25 s). There was a near perfect correlation between the CODAT and IAR (r = 0.92), and very large correlations with the 20-m sprint (r = 0.75-0.76), suggesting that the CODAT was a valid change-of-direction speed test. Due to movement specificity, the CODAT has value for field sport

  1. Is qPCR a Reliable Indicator of Cyanotoxin Risk in Freshwater?

    Science.gov (United States)

    Pacheco, Ana Beatriz F.; Guedes, Iame A.; Azevedo, Sandra M.F.O.

    2016-01-01

    The wide distribution of cyanobacteria in aquatic environments leads to the risk of water contamination by cyanotoxins, which generate environmental and public health issues. Measurements of cell densities or pigment contents allow both the early detection of cellular growth and bloom monitoring, but these methods are not sufficiently accurate to predict actual cyanobacterial risk. To quantify cyanotoxins, analytical methods are considered the gold standards, but they are laborious, expensive, time-consuming and available in a limited number of laboratories. In cyanobacterial species with toxic potential, cyanotoxin production is restricted to some strains, and blooms can contain varying proportions of both toxic and non-toxic cells, which are morphologically indistinguishable. The sequencing of cyanobacterial genomes led to the description of gene clusters responsible for cyanotoxin production, which paved the way for the use of these genes as targets for PCR and then quantitative PCR (qPCR). Thus, the quantification of cyanotoxin genes appeared as a new method for estimating the potential toxicity of blooms. This raises a question concerning whether qPCR-based methods would be a reliable indicator of toxin concentration in the environment. Here, we review studies that report the parallel detection of microcystin genes and microcystin concentrations in natural populations and also a smaller number of studies dedicated to cylindrospermopsin and saxitoxin. We discuss the possible issues associated with the contradictory findings reported to date, present methodological limitations and consider the use of qPCR as an indicator of cyanotoxin risk. PMID:27338471

  2. Is qPCR a Reliable Indicator of Cyanotoxin Risk in Freshwater?

    Directory of Open Access Journals (Sweden)

    Ana Beatriz F. Pacheco

    2016-06-01

    Full Text Available The wide distribution of cyanobacteria in aquatic environments leads to the risk of water contamination by cyanotoxins, which generate environmental and public health issues. Measurements of cell densities or pigment contents allow both the early detection of cellular growth and bloom monitoring, but these methods are not sufficiently accurate to predict actual cyanobacterial risk. To quantify cyanotoxins, analytical methods are considered the gold standards, but they are laborious, expensive, time-consuming and available in a limited number of laboratories. In cyanobacterial species with toxic potential, cyanotoxin production is restricted to some strains, and blooms can contain varying proportions of both toxic and non-toxic cells, which are morphologically indistinguishable. The sequencing of cyanobacterial genomes led to the description of gene clusters responsible for cyanotoxin production, which paved the way for the use of these genes as targets for PCR and then quantitative PCR (qPCR. Thus, the quantification of cyanotoxin genes appeared as a new method for estimating the potential toxicity of blooms. This raises a question concerning whether qPCR-based methods would be a reliable indicator of toxin concentration in the environment. Here, we review studies that report the parallel detection of microcystin genes and microcystin concentrations in natural populations and also a smaller number of studies dedicated to cylindrospermopsin and saxitoxin. We discuss the possible issues associated with the contradictory findings reported to date, present methodological limitations and consider the use of qPCR as an indicator of cyanotoxin risk.

  3. Extreme storms, sea level rise, and coastal change: implications for infrastructure reliability in the Gulf of Mexico

    Science.gov (United States)

    Anarde, K.; Kameshwar, S.; Irza, N.; Lorenzo-Trueba, J.; Nittrouer, J. A.; Padgett, J.; Bedient, P. B.

    2016-12-01

    Predicting coastal infrastructure reliability during hurricane events is important for risk-based design and disaster planning, such as delineating viable emergency response routes. Previous research has focused on either infrastructure vulnerability to coastal flooding or the impact of changing sea level and landforms on surge dynamics. Here we investigate the combined impact of sea level, morphology, and coastal flooding on the reliability of highway bridges - the only access points between barrier islands and mainland communities - during future extreme storms. We forward model coastal flooding for static projections of geomorphic change using ADCIRC+SWAN. First-order parameters that are adjusted include sea level and elevation. These are varied for each storm simulation to evaluate relative impact on the reliability of bridges surrounding Freeport, TX. Simulated storms include both synthetic and historical events, which are classified by intensity using the storm's integrated kinetic energy, a metric for surge generation potential. Reliability is estimated through probability of failure - given wave and surge loads - and time inundated. Findings include that: 1) bridge reliability scales inversely with surge height, and 2) sea level rise reduces bridge reliability due to a monotonic increase in surge height. The impact of a shifting landscape on bridge reliability is more complex: barrier island rollback can increase or decrease inundation times for storms of different intensity due to changes in wind-setup and back-barrier bay interactions. Initial storm surge readily inundates the coastal landscape during large intensity storms, however the draining of inland bays following storm passage is significantly impeded by the barrier. From a coastal engineering standpoint, we determine that to protect critical infrastructure, efforts now implemented that nourish low-lying barriers may be enhanced by also armoring back-bay coastlines and elevating bridge approach

  4. Transmission cost allocation based on power flow tracing considering reliability benefit

    International Nuclear Information System (INIS)

    Leepreechanon, N.; Singharerg, S.; Padungwech, W.; Nakawiro, W.; Eua-Arporn, B.; David, A.K.

    2007-01-01

    Power transmission networks must be able to accommodate the continuously growing demand for reliable and economical electricity. This paper presented a method to allocate transmission use and reliability cost to both generators and end-consumers. Although transmission cost allocation methods change depending on the local context of the electric power industry, there is a common principle that transmission line capacity should be properly allocated to accommodate actual power delivery with an adequate reliability margin. The method proposed in this paper allocates transmission embedded cost to both generators and loads in an equitable manner, incorporating probability indices to allocate transmission reliability margin among users in both supply and demand sides. The application of the proposed method was illustrated using Bialek's tracing method on a multiple-circuit, six-bus transmission system. Probabilistic indices known as the transmission internal reliability margin (TIRM) and transmission external reliability margin (TERM) decomposed from the transmission reliability margin (TRM) were introduced, making true cost of using overall transmission facilities. 6 refs., 11 tabs., 5 figs

  5. Track 2- major components reliability and materials issues. Some performance indicators of PWR steam generators

    International Nuclear Information System (INIS)

    Milivojevic, S.; Spasojevic, D.; Riznic, J.

    2001-01-01

    The monitoring of operational performance is a crucial aspect of the management of equipment operation and maintenance in many industries, including nuclear and thermal power plants. Monitoring involves the collection and analysis of data on the operation. In these paper an analysis was made of steam generators in operation, i.e., their malfunctions during the plant life cycle with the aim of studying the characteristics of failure rate and repair rate. These values are necessary parameters if we are to determine the reliability and availability of the steam generator as a basis for the analysis of its effect on the safety and efficiency of the nuclear power plant. We analyzed IAEA available data for period from 1971 to 1998. Each steam generator was monitored individually during plants' lifetime. The data on steam generator failures were presented in uniform format, allowing the consistency in failure classification and data reporting. Operational presence of the analyzed steam generators is given for each calendar year and each lifetime year: the failure rate l and repair rate m with associated boundaries are calculated. The general trends in calendar years performance indicators (μ) of steam generators is investigated. The distributions of lifetime l and m are formed, as a complement to the analysis of calendar years performance indicators. With aspect of steam generators influence on reliability and availability of nuclear power plants, the empirical probability distribution for failure rates and repair rates are also constructed. (author)

  6. The two errors of using the within-subject standard deviation (WSD) as the standard error of a reliable change index.

    Science.gov (United States)

    Maassen, Gerard H

    2010-08-01

    In this Journal, Lewis and colleagues introduced a new Reliable Change Index (RCI(WSD)), which incorporated the within-subject standard deviation (WSD) of a repeated measurement design as the standard error. In this note, two opposite errors in using WSD this way are demonstrated. First, being the standard error of measurement of only a single assessment makes WSD too small when practice effects are absent. Then, too many individuals will be designated reliably changed. Second, WSD can grow unlimitedly to the extent that differential practice effects occur. This can even make RCI(WSD) unable to detect any reliable change.

  7. Assessing changes in drought characteristics with standardized indices

    Science.gov (United States)

    Vidal, Jean-Philippe; Najac, Julien; Martin, Eric; Franchistéguy, Laurent; Soubeyroux, Jean-Michel

    2010-05-01

    Standardized drought indices like the Standardized Precipitation Index (SPI) are more and more frequently adopted for drought reconstruction, monitoring and forecasting, and the SPI has been recently recommended by the World Meteorological Organization to characterize meteorological droughts. Such indices are based on the statistical distribution of a hydrometeorological variable (e.g., precipitation) in a given reference climate, and a drought event is defined as a period with continuously negative index values. Because of the way these indices are constructed, some issues may arise when using them in a non-stationnary climate. This work thus aims at highlighting such issues and demonstrating the different ways these indices may - or may not - be applied and interpreted in the context of an anthropogenic climate change. Three major points are detailed through examples taken from both a high-resolution gridded reanalysis dataset over France and transient projections from the ARPEGE general circulation model downscaled over France. The first point deals with the choice of the reference climate, and more specifically its type (from observations/reanalysis or from present-day modelled climate) and its record period. Second, the interpretation of actual changes are closely linked with the type of the selected drought feature over a future period: mean index value, under-threshold frequency, or drought event characteristics (number, mean duration and magnitude, seasonality, etc.). Finally, applicable approaches as well as related uncertainties depend on the availability of data from a future climate, whether in the form of a fully transient time series from present-day or only a future time slice. The projected evolution of drought characteristics under climate change must inform present decisions on long-term water resources planning. An assessment of changes in drought characteristics should therefore provide water managers with appropriate information that can help

  8. Global Malmquist indices of productivity change in Egyptian wheat production

    Energy Technology Data Exchange (ETDEWEB)

    Elasraag, Y.H.; Alarcón, S.

    2017-07-01

    This study aims to measure the total factor productivity of the main govern orates of wheat production in Egypt during the time period 1990-2012 and decompose it into technical change, efficiency change and scale change. We used Global Malmquist TFP index as a non-parametric approach. The results indicated that the contribution of technical change component is more important than the efficiency change component. In fact technical change rose, 25.7%, while efficiency change presented a little decline, 3.7%. The decomposition of efficiency change indicated that the main problem of wheat production in Egypt was scale efficiency that worsened by 5.5%.

  9. Will male advertisement be a reliable indicator of paternal care, if offspring survival depends on male care?

    Science.gov (United States)

    Kelly, Natasha B; Alonzo, Suzanne H

    2009-09-07

    Existing theory predicts that male signalling can be an unreliable indicator of paternal care, but assumes that males with high levels of mating success can have high current reproductive success, without providing any parental care. As a result, this theory does not hold for the many species where offspring survival depends on male parental care. We modelled male allocation of resources between advertisement and care for species with male care where males vary in quality, and the effect of care and advertisement on male fitness is multiplicative rather than additive. Our model predicts that males will allocate proportionally more of their resources to whichever trait (advertisement or paternal care) is more fitness limiting. In contrast to previous theory, we find that male advertisement is always a reliable indicator of paternal care and male phenotypic quality (e.g. males with higher levels of advertisement never allocate less to care than males with lower levels of advertisement). Our model shows that the predicted pattern of male allocation and the reliability of male signalling depend very strongly on whether paternal care is assumed to be necessary for offspring survival and how male care affects offspring survival and male fitness.

  10. Wildlife as biological indicators for assessing impacts of climate change

    International Nuclear Information System (INIS)

    Diamond, A.W.

    1990-01-01

    Estimates of the impacts of climate change on wildlife are necessarily constrained by knowledge of the effects of climate on wildlife. A review is presented of the better-known impacts of climate on wildlife, examining their utility as ecological indicators. The most obvious feature of any species is its geographic distribution, or range. Climate may affect distribution indirectly through effects on habitat, directly through physiological effects, or most probably, through both. Impacts can include changes in distribution of habitat, changes in distribution of species, and changes in migration routes. Direct effects of climate include timing and success of breeding, timing and success of migration, winter survival, and extreme events. Distribution changes are powerful integrators of ecosystem-level events, but poor indicators of particular changes. Changes in the timing of migration, and the phenology of breeding, are more directly determined by weather events and hence will be better indicators of changing climate. Detailed knowledge of effects of climate on timing and success of breeding is available for only a few species, and has not been carefully synthesized with a view to using such variables as climatic indicators. Temperature maxima and minima, frost-free and degree days, and estimates of precipitation on finer scales, both temporal and geographic, are needed to predict the effects of climate change on wildlife. 48 refs

  11. Reliability and validity of the de Morton Mobility Index in individuals with sub-acute stroke.

    Science.gov (United States)

    Braun, Tobias; Marks, Detlef; Thiel, Christian; Grüneberg, Christian

    2018-02-04

    To establish the validity and reliability of the de Morton Mobility Index (DEMMI) in patients with sub-acute stroke. This cross-sectional study was performed in a neurological rehabilitation hospital. We assessed unidimensionality, construct validity, internal consistency reliability, inter-rater reliability, minimal detectable change and possible floor and ceiling effects of the DEMMI in adult patients with sub-acute stroke. The study included a total sample of 121 patients with sub-acute stroke. We analysed validity (n = 109) and reliability (n = 51) in two sub-samples. Rasch analysis indicated unidimensionality with an overall fit to the model (chi-square = 12.37, p = 0.577). All hypotheses on construct validity were confirmed. Internal consistency reliability (Cronbach's alpha = 0.94) and inter-rater reliability (intraclass correlation coefficient = 0.95; 95% confidence interval: 0.92-0.97) were excellent. The minimal detectable change with 90% confidence was 13 points. No floor or ceiling effects were evident. These results indicate unidimensionality, sufficient internal consistency reliability, inter-rater reliability, and construct validity of the DEMMI in patients with a sub-acute stroke. Advantages of the DEMMI in clinical application are the short administration time, no need for special equipment and interval level data. The de Morton Mobility Index, therefore, may be a useful performance-based bedside test to measure mobility in individuals with a sub-acute stroke across the whole mobility spectrum. Implications for Rehabilitation The de Morton Mobility Index (DEMMI) is an unidimensional measurement instrument of mobility in individuals with sub-acute stroke. The DEMMI has excellent internal consistency and inter-rater reliability, and sufficient construct validity. The minimal detectable change of the DEMMI with 90% confidence in stroke rehabilitation is 13 points. The lack of any floor or ceiling effects on hospital admission indicates

  12. Environmental health indicators of climate change for the United States: findings from the State Environmental Health Indicator Collaborative.

    Science.gov (United States)

    English, Paul B; Sinclair, Amber H; Ross, Zev; Anderson, Henry; Boothe, Vicki; Davis, Christine; Ebi, Kristie; Kagey, Betsy; Malecki, Kristen; Shultz, Rebecca; Simms, Erin

    2009-11-01

    To develop public health adaptation strategies and to project the impacts of climate change on human health, indicators of vulnerability and preparedness along with accurate surveillance data on climate-sensitive health outcomes are needed. We researched and developed environmental health indicators for inputs into human health vulnerability assessments for climate change and to propose public health preventative actions. We conducted a review of the scientific literature to identify outcomes and actions that were related to climate change. Data sources included governmental and nongovernmental agencies and the published literature. Sources were identified and assessed for completeness, usability, and accuracy. Priority was then given to identifying longitudinal data sets that were applicable at the state and community level. We present a list of surveillance indicators for practitioners and policy makers that include climate-sensitive health outcomes and environmental and vulnerability indicators, as well as mitigation, adaptation, and policy indicators of climate change. A review of environmental health indicators for climate change shows that data exist for many of these measures, but more evaluation of their sensitivity and usefulness is needed. Further attention is necessary to increase data quality and availability and to develop new surveillance databases, especially for climate-sensitive morbidity.

  13. Extracting information from an ensemble of GCMs to reliably assess future global runoff change

    NARCIS (Netherlands)

    Sperna Weiland, F.C.; Beek, L.P.H. van; Weerts, A.H.; Bierkens, M.F.P.

    2011-01-01

    Future runoff projections derived from different global climate models (GCMs) show large differences. Therefore, within this study the, information from multiple GCMs has been combined to better assess hydrological changes. For projections of precipitation and temperature the Reliability ensemble

  14. Follow-up of CT-derived airway wall thickness : Correcting for changes in inspiration level improves reliability

    NARCIS (Netherlands)

    Pompe, Esther; van Rikxoort, Eva M; Mets, Onno M; Charbonnier, Jean-Paul; Kuhnigk, Jan-Martin; de Koning, Harry J; Oudkerk, Matthijs; Vliegenthart, Rozemarijn; Zanen, Pieter; Lammers, Jan-Willem J; van Ginneken, Bram; de Jong, Pim A; Mohamed Hoesein, Firdaus A A

    2016-01-01

    OBJECTIVES: Airway wall thickness (AWT) is affected by changes in lung volume. This study evaluated whether correcting AWT on computed tomography (CT) for differences in inspiration level improves measurement agreement, reliability, and power to detect changes over time. METHODS: Participants of the

  15. Follow-up of CT-derived airway wall thickness : Correcting for changes in inspiration level improves reliability

    NARCIS (Netherlands)

    Pompe, Esther; van Rikxoort, Eva M.; Mets, Onno M.; Charbonnier, Jean-Paul; Kuhnigk, Jan-Martin; de Koning, Harry J.; Oudkerk, Matthijs; Vliegenthart, Rozemarijn; Zanen, Pieter; Lammers, Jan-Willem J.; van Ginneken, Bram; de Jong, Pim A.; Hoesein, Firdaus A. A. Mohamed

    2016-01-01

    Objectives: Airway wall thickness (AWT) is affected by changes in lung volume. This study evaluated whether correcting AWT on computed tomography (CT) for differences in inspiration level improves measurement agreement, reliability, and power to detect changes over time. Methods: Participants of the

  16. Reliability, validity, and sensitivity to change of the lower extremity functional scale in individuals affected by stroke.

    Science.gov (United States)

    Verheijde, Joseph L; White, Fred; Tompkins, James; Dahl, Peder; Hentz, Joseph G; Lebec, Michael T; Cornwall, Mark

    2013-12-01

    To investigate reliability, validity, and sensitivity to change of the Lower Extremity Functional Scale (LEFS) in individuals affected by stroke. The secondary objective was to test the validity and sensitivity of a single-item linear analog scale (LAS) of function. Prospective cohort reliability and validation study. A single rehabilitation department in an academic medical center. Forty-three individuals receiving neurorehabilitation for lower extremity dysfunction after stroke were studied. Their ages ranged from 32 to 95 years, with a mean of 70 years; 77% were men. Test-retest reliability was assessed by calculating the classical intraclass correlation coefficient, and the Bland-Altman limits of agreement. Validity was assessed by calculating the Pearson correlation coefficient between the instruments. Sensitivity to change was assessed by comparing baseline scores with end of treatment scores. Measurements were taken at baseline, after 1-3 days, and at 4 and 8 weeks. The LEFS, Short-Form-36 Physical Function Scale, Berg Balance Scale, Six-Minute Walk Test, Five-Meter Walk Test, Timed Up-and-Go test, and the LAS of function were used. The test-retest reliability of the LEFS was found to be excellent (ICC = 0.96). Correlated with the 6 other measures of function studied, the validity of the LEFS was found to be moderate to high (r = 0.40-0.71). Regarding the sensitivity to change, the mean LEFS scores from baseline to study end increased 1.2 SD and for LAS 1.1 SD. LEFS exhibits good reliability, validity, and sensitivity to change in patients with lower extremity impairments secondary to stroke. Therefore, the LEFS can be a clinically efficient outcome measure in the rehabilitation of patients with subacute stroke. The LAS is shown to be a time-saving and reasonable option to track changes in a patient's functional status. Copyright © 2013 American Academy of Physical Medicine and Rehabilitation. Published by Elsevier Inc. All rights reserved.

  17. Reliability of drivers in urban intersections.

    Science.gov (United States)

    Gstalter, Herbert; Fastenmeier, Wolfgang

    2010-01-01

    The concept of human reliability has been widely used in industrial settings by human factors experts to optimise the person-task fit. Reliability is estimated by the probability that a task will successfully be completed by personnel in a given stage of system operation. Human Reliability Analysis (HRA) is a technique used to calculate human error probabilities as the ratio of errors committed to the number of opportunities for that error. To transfer this notion to the measurement of car driver reliability the following components are necessary: a taxonomy of driving tasks, a definition of correct behaviour in each of these tasks, a list of errors as deviations from the correct actions and an adequate observation method to register errors and opportunities for these errors. Use of the SAFE-task analysis procedure recently made it possible to derive driver errors directly from the normative analysis of behavioural requirements. Driver reliability estimates could be used to compare groups of tasks (e.g. different types of intersections with their respective regulations) as well as groups of drivers' or individual drivers' aptitudes. This approach was tested in a field study with 62 drivers of different age groups. The subjects drove an instrumented car and had to complete an urban test route, the main features of which were 18 intersections representing six different driving tasks. The subjects were accompanied by two trained observers who recorded driver errors using standardized observation sheets. Results indicate that error indices often vary between both the age group of drivers and the type of driving task. The highest error indices occurred in the non-signalised intersection tasks and the roundabout, which exactly equals the corresponding ratings of task complexity from the SAFE analysis. A comparison of age groups clearly shows the disadvantage of older drivers, whose error indices in nearly all tasks are significantly higher than those of the other groups

  18. A generic Approach for Reliability Predictions considering non-uniformly Deterioration Behaviour

    International Nuclear Information System (INIS)

    Krause, Jakob; Kabitzsch, Klaus

    2012-01-01

    Predictive maintenance offers the possibility to prognosticate the remaining time until a maintenance action of a machine has to be scheduled. Unfortunately, current predictive maintenance solutions are only suitable for very specific use cases like reliability predictions based on vibration monitoring. Furthermore, they do not consider the fact that machines may deteriorate non-uniformly, depending on external influences (e.g., the work piece material in a milling machine or the changing fruit acid concentration in a bottling plant). In this paper two concepts for a generic predictive maintenance solution which also considers non-uniformly aging behaviour are introduced. The first concept is based on system models representing the health state of a technical system. As these models are usually statically (viz. without a timely dimension) their coefficients are determined periodically and the resulting time series is used as aging indicator. The second concept focuses on external influences (contexts) which change the behaviour of the previous mentioned aging indicators in order to increase the accuracy of reliability predictions. Therefore, context-depended time series models are determined and used to predict machine reliability. Both concepts were evaluated on data of an air ventilation system. Thereby, it could be shown that they are suitable to determine aging indicators in a generic way and to incorporate external influences in the reliability prediction. Through this, the quality of reliability predictions can be significantly increased. In reality this leads to a more accurate scheduling of maintenance actions. Furthermore, the generic character of the solutions makes the concepts suitable for a wide range of aging processes.

  19. A study of operational and testing reliability in software reliability analysis

    International Nuclear Information System (INIS)

    Yang, B.; Xie, M.

    2000-01-01

    Software reliability is an important aspect of any complex equipment today. Software reliability is usually estimated based on reliability models such as nonhomogeneous Poisson process (NHPP) models. Software systems are improving in testing phase, while it normally does not change in operational phase. Depending on whether the reliability is to be predicted for testing phase or operation phase, different measure should be used. In this paper, two different reliability concepts, namely, the operational reliability and the testing reliability, are clarified and studied in detail. These concepts have been mixed up or even misused in some existing literature. Using different reliability concept will lead to different reliability values obtained and it will further lead to different reliability-based decisions made. The difference of the estimated reliabilities is studied and the effect on the optimal release time is investigated

  20. Sensitivity of health sector indicators' response to climate change in Ghana.

    Science.gov (United States)

    Dovie, Delali B K; Dzodzomenyo, Mawuli; Ogunseitan, Oladele A

    2017-01-01

    There is accumulating evidence that the emerging burden of global climate change threatens the fidelity of routine indicators for disease detection and management of risks to public health. The threat partially reflects the conservative character of the health sector and the reluctance to adopt new indicators, despite the growing awareness that existing environmental health indicators were developed to respond to risks that may no longer be relevant, and are too simplistic to also act as indicators for newer global-scale risk factors. This study sought to understand the scope of existing health indicators, while aiming to discover new indicators for building resilience against three climate sensitive diseases (cerebro spinal meningitis, malaria and diarrhea). Therefore, new potential indicators derived from human and biophysical origins were developed to complement existing health indicators, thereby creating climate-sensitive battery of robust composite indices of resilience in health planning. Using Ghana's health sector as a case study systematic international literature review, national expert consultation, and focus group outcomes yielded insights into the relevance, sensitivity and impacts of 45 indicators in 11 categories in responding to climate change. In total, 65% of the indicators were sensitive to health impacts of climate change; 24% acted directly; 31% synergistically; and 45% indirectly, with indicator relevance strongly associated with type of health response. Epidemiological indicators (e.g. morbidity) and health demographic indicators (e.g. population structure) require adjustments with external indicators (e.g. biophysical, policy) to be resilient to climate change. Therefore, selective integration of social and ecological indicators with existing public health indicators improves the fidelity of the health sector to adopt more robust planning of interdependent systems to build resilience. The study highlights growing uncertainties in

  1. Developing Health-Related Indicators of Climate Change: Australian Stakeholder Perspectives.

    Science.gov (United States)

    Navi, Maryam; Hansen, Alana; Nitschke, Monika; Hanson-Easey, Scott; Pisaniello, Dino

    2017-05-22

    Climate-related health indicators are potentially useful for tracking and predicting the adverse public health effects of climate change, identifying vulnerable populations, and monitoring interventions. However, there is a need to understand stakeholders' perspectives on the identification, development, and utility of such indicators. A qualitative approach was used, comprising semi-structured interviews with key informants and service providers from government and non-government stakeholder organizations in South Australia. Stakeholders saw a need for indicators that could enable the monitoring of health impacts and time trends, vulnerability to climate change, and those which could also be used as communication tools. Four key criteria for utility were identified, namely robust and credible indicators, specificity, data availability, and being able to be spatially represented. The variability of risk factors in different regions, lack of resources, and data and methodological issues were identified as the main barriers to indicator development. This study demonstrates a high level of stakeholder awareness of the health impacts of climate change, and the need for indicators that can inform policy makers regarding interventions.

  2. The changing Chinese SEA indicator guidelines: Top-down or bottom-up?

    International Nuclear Information System (INIS)

    Gao, Jingjing; Christensen, Per; Kørnøv, Lone

    2014-01-01

    In the last decades, China has introduced a set of indicators to guide the Strategic Environmental Assessment (SEA) practice. The most recent indicator system proposed in 2009 is based on sector-specific guidelines and it found its justification in past negative experiences with more general guidelines (from 2003), which were mostly inspired by, or copied from, international experiences. Based on interviews with practitioners, researchers and administrators, we map and analyse the change in the national guidelines. This analysis is based on a description of the indicators that makes it possible to discern different aggregation levels of indicators and then trace the changes occurring under two sets of guidelines. The analysis also reveals the reasons and rationales behind the changes found in the guidelines. This analysis is inspired by implementation theory and a description of some of the more general trends in the development of SEA and other environmental policies in a recent Chinese context. Beside a more top-down, intentional approach specifying indicators for different sectors based on Chinese experiences from the preceding years, another significant change, following the new guidelines, is a more bottom-up approach which gives more discretion to practitioners. This entails a call for practitioners to make decisions on indicators, which involves an interpretation of the ones present in sector guidance. Highlights: • Focusing on the new Chinese national SEA guidelines proposed in 2009 • Mapping and analysing the most recent change in the indicator system • Revealing the reasons and rationales behind the changes found in the new guidelines • A top-down intention specifying indicators for different sectors • A bottom-up effect in giving discretion and interpretation of using indicators

  3. The changing Chinese SEA indicator guidelines: Top-down or bottom-up?

    Energy Technology Data Exchange (ETDEWEB)

    Gao, Jingjing, E-mail: Jingjing@plan.aau.dk; Christensen, Per; Kørnøv, Lone

    2014-01-15

    In the last decades, China has introduced a set of indicators to guide the Strategic Environmental Assessment (SEA) practice. The most recent indicator system proposed in 2009 is based on sector-specific guidelines and it found its justification in past negative experiences with more general guidelines (from 2003), which were mostly inspired by, or copied from, international experiences. Based on interviews with practitioners, researchers and administrators, we map and analyse the change in the national guidelines. This analysis is based on a description of the indicators that makes it possible to discern different aggregation levels of indicators and then trace the changes occurring under two sets of guidelines. The analysis also reveals the reasons and rationales behind the changes found in the guidelines. This analysis is inspired by implementation theory and a description of some of the more general trends in the development of SEA and other environmental policies in a recent Chinese context. Beside a more top-down, intentional approach specifying indicators for different sectors based on Chinese experiences from the preceding years, another significant change, following the new guidelines, is a more bottom-up approach which gives more discretion to practitioners. This entails a call for practitioners to make decisions on indicators, which involves an interpretation of the ones present in sector guidance. Highlights: • Focusing on the new Chinese national SEA guidelines proposed in 2009 • Mapping and analysing the most recent change in the indicator system • Revealing the reasons and rationales behind the changes found in the new guidelines • A top-down intention specifying indicators for different sectors • A bottom-up effect in giving discretion and interpretation of using indicators.

  4. Reliability of standing weight-bearing (0.25T) MR imaging findings and positional changes in the lumbar spine

    Energy Technology Data Exchange (ETDEWEB)

    Hansen, Bjarke B.; Bliddal, Henning [Department of Reumatology, Copenhagen University Hospital, The Parker Institute, Koebenhavn Oe (Denmark); Hansen, Philip; Christensen, Anders F.; Trampedach, Charlotte; Rasti, Zoreh; Boesen, Mikael [Copenhagen University Hospital, Department of Radiology, Koebenhavn Oe (Denmark)

    2018-01-15

    To test the reliability and absolute agreement of common degenerative findings in standing positional magnetic resonance imaging (pMRI). Low back pain patients with and without sciatica were consecutively enrolled to undergo a supine and standing pMRI. Three readers independently evaluated the standing pMRI for herniation, spinal stenosis, spondylolisthesis, HIZ lesions and facet joint effusion. The evaluation included a semi-quantitative grading of spinal stenosis, foraminal stenosis and spinal nerve root compression. The standing pMRI images were evaluated with full access to supine MRI. In case lower grades or the degenerative findings were not present in the supine images, this was reported separately as position-dependent changes. A subsample of 20 pMRI examinations was reevaluated after two months. The reproducibility was assessed by inter- and intra-reader reliability (kappa statistic) and absolute agreement between readers. Fifty-six patients were included in this study. There was fair-to-substantial inter-reader reliability (κ 0.47 to 0.82) and high absolute agreement (72.3% to 99.1%) for the pMRI findings. The intra-reader assessment showed similar reliability and agreement (κ 0.36 to 0.85; absolute agreement: 62.5% to 98.8%). Positional changes between the supine and standing position showed a fair-to-moderate inter- and intra-reader reliability (κ 0.25 to 0.52; absolute agreement: 97.0% to 99.1). Evaluation of the lumbar spine for degenerative findings by standing pMRI has acceptable reproducibility; however, positional changes from the supine to the standing position as an independent outcome should be interpreted with caution because of lower reliability, which calls for further standardisation. (orig.)

  5. Reliability of standing weight-bearing (0.25T) MR imaging findings and positional changes in the lumbar spine

    International Nuclear Information System (INIS)

    Hansen, Bjarke B.; Bliddal, Henning; Hansen, Philip; Christensen, Anders F.; Trampedach, Charlotte; Rasti, Zoreh; Boesen, Mikael

    2018-01-01

    To test the reliability and absolute agreement of common degenerative findings in standing positional magnetic resonance imaging (pMRI). Low back pain patients with and without sciatica were consecutively enrolled to undergo a supine and standing pMRI. Three readers independently evaluated the standing pMRI for herniation, spinal stenosis, spondylolisthesis, HIZ lesions and facet joint effusion. The evaluation included a semi-quantitative grading of spinal stenosis, foraminal stenosis and spinal nerve root compression. The standing pMRI images were evaluated with full access to supine MRI. In case lower grades or the degenerative findings were not present in the supine images, this was reported separately as position-dependent changes. A subsample of 20 pMRI examinations was reevaluated after two months. The reproducibility was assessed by inter- and intra-reader reliability (kappa statistic) and absolute agreement between readers. Fifty-six patients were included in this study. There was fair-to-substantial inter-reader reliability (κ 0.47 to 0.82) and high absolute agreement (72.3% to 99.1%) for the pMRI findings. The intra-reader assessment showed similar reliability and agreement (κ 0.36 to 0.85; absolute agreement: 62.5% to 98.8%). Positional changes between the supine and standing position showed a fair-to-moderate inter- and intra-reader reliability (κ 0.25 to 0.52; absolute agreement: 97.0% to 99.1). Evaluation of the lumbar spine for degenerative findings by standing pMRI has acceptable reproducibility; however, positional changes from the supine to the standing position as an independent outcome should be interpreted with caution because of lower reliability, which calls for further standardisation. (orig.)

  6. Reliability of standing weight-bearing (0.25T) MR imaging findings and positional changes in the lumbar spine.

    Science.gov (United States)

    Hansen, Bjarke B; Hansen, Philip; Christensen, Anders F; Trampedach, Charlotte; Rasti, Zoreh; Bliddal, Henning; Boesen, Mikael

    2018-01-01

    To test the reliability and absolute agreement of common degenerative findings in standing positional magnetic resonance imaging (pMRI). Low back pain patients with and without sciatica were consecutively enrolled to undergo a supine and standing pMRI. Three readers independently evaluated the standing pMRI for herniation, spinal stenosis, spondylolisthesis, HIZ lesions and facet joint effusion. The evaluation included a semi-quantitative grading of spinal stenosis, foraminal stenosis and spinal nerve root compression. The standing pMRI images were evaluated with full access to supine MRI. In case lower grades or the degenerative findings were not present in the supine images, this was reported separately as position-dependent changes. A subsample of 20 pMRI examinations was reevaluated after two months. The reproducibility was assessed by inter- and intra-reader reliability (kappa statistic) and absolute agreement between readers. Fifty-six patients were included in this study. There was fair-to-substantial inter-reader reliability (κ 0.47 to 0.82) and high absolute agreement (72.3% to 99.1%) for the pMRI findings. The intra-reader assessment showed similar reliability and agreement (κ 0.36 to 0.85; absolute agreement: 62.5% to 98.8%). Positional changes between the supine and standing position showed a fair-to-moderate inter- and intra-reader reliability (κ 0.25 to 0.52; absolute agreement: 97.0% to 99.1). Evaluation of the lumbar spine for degenerative findings by standing pMRI has acceptable reproducibility; however, positional changes from the supine to the standing position as an independent outcome should be interpreted with caution because of lower reliability, which calls for further standardisation.

  7. Assessment of weather indicators for possible climate change

    International Nuclear Information System (INIS)

    Maqssood, H.; Ahmed, S.I.

    2014-01-01

    From 20 century onwards, a great concern has been expressed regarding global climate change. This study attempts to perform detailed analysis of temperature and precipitation for Karachi city of Pakistan, to assess the possible climate change, using two data sets (51-year data: 1961-2012 and 31-year data: 1981-2012) for different parameters. Trends were generated using linear regression (LR) and Mann-Kendall (MK), which depicted that daily and annual temperatures were increasing, with changes in minimum temperature being more significant than maximum temperature. Analyses also showed increase in extreme temperature at night and during winter, showing that urbanization was a major factor, as the heat from buildings trapped in between dissipates at nights. The daily and monthly precipitation levels increased in contrast to annual precipitation trend, which is justified by the averaged monthly analysis showing that decreasing trends were much more significant than increasing trends. In addition, monthly precipitation showed an increase of 4.3 mm, using LR and MK test. It can be noticed that two extreme winter months (December and January) and two extreme hot months (May and October) received increased rainfall. However, statistical analyses showed overall annual decrease in rainfall. Furthermore, decadal analysis indicated sinusoidal behaviour of change in climate indicators; making climatic change evident but cyclic in nature. (author)

  8. Greenhouse gas emissions considered responsible for climate change: Environmental indicators

    International Nuclear Information System (INIS)

    Vialetto, G.; Venanzi, M.; Gaudioso, D.

    1993-09-01

    This paper concerns the more significant environmental indicators related to the emissions of radiatively and chemically/photochemically active trace gases. Reference is made to the preliminary work of the Intergovernmental Panel on Climate Change (IPCC) and to the proposals made in the framework of the international negotiation on climate change. Aiming to contribute to the definition of a national strategy for the reduction of greenhouse gases emissions, this paper proposes a possible application of the indicators. The calculation of the indicators is based on the emission estimate performed by ENEA (Italian National Agency for Energy, New Technologies and the Environment) for the Report on the State of the Environment edited by the Italian Ministry of the Environment. Finally, the paper suggests an application of such indicators for the international negotiation, in the framework of the Italian proposal for the Convention on climate change

  9. Visual-Haptic Integration: Cue Weights are Varied Appropriately, to Account for Changes in Haptic Reliability Introduced by Using a Tool

    Directory of Open Access Journals (Sweden)

    Chie Takahashi

    2011-10-01

    Full Text Available Tools such as pliers systematically change the relationship between an object's size and the hand opening required to grasp it. Previous work suggests the brain takes this into account, integrating visual and haptic size information that refers to the same object, independent of the similarity of the ‘raw’ visual and haptic signals (Takahashi et al., VSS 2009. Variations in tool geometry also affect the reliability (precision of haptic size estimates, however, because they alter the change in hand opening caused by a given change in object size. Here, we examine whether the brain appropriately adjusts the weights given to visual and haptic size signals when tool geometry changes. We first estimated each cue's reliability by measuring size-discrimination thresholds in vision-alone and haptics-alone conditions. We varied haptic reliability using tools with different object-size:hand-opening ratios (1:1, 0.7:1, and 1.4:1. We then measured the weights given to vision and haptics with each tool, using a cue-conflict paradigm. The weight given to haptics varied with tool type in a manner that was well predicted by the single-cue reliabilities (MLE model; Ernst and Banks, 2002. This suggests that the process of visual-haptic integration appropriately accounts for variations in haptic reliability introduced by different tool geometries.

  10. [Assessment of the validity and reliability of the processes of change scale based on the transtheoretical model of vegetable consumption behavior in Japanese male workers].

    Science.gov (United States)

    Kushida, Osamu; Murayama, Nobuko

    2012-12-01

    A core construct of the Transtheoretical model is that the processes and stages of change are strongly related to observable behavioral changes. We created the Processes of Change Scale of vegetable consumption behavior and examined the validity and reliability of this scale. In September 2009, a self-administered questionnaire was administered to male Japanese employees, aged 20-59 years, working at 20 worksites in Niigata City in Japan. The stages of change (precontempration, contemplation, preparation, action, and maintenance stage) were measured using 2 items that assessed participants' current implementation of the target behavior (eating 5 or more servings of vegetables per day) and their readiness to change their habits. The Processes of Change Scale of vegetable consumption behavior comprised 10 items assessing 5 cognitive processes (consciousness raising, emotional arousal, environmental reevaluation, self-reevaluation, and social liberation) and 5 behavioral processes (commitment, rewards, helping relationships, countering, and environment control). Each item was selected from an existing scale. Decisional balance (pros [2 items] and cons [2 items]), and self-efficacy (3 items) were also assessed, because these constructs were considered to be relevant to the processes of change. The internal consistency reliability of the scale was examined using Cronbach's alpha. Its construct validity was examined using a factor analysis of the processes of change, decisional balance, and self-efficacy variables, while its criterion-related validity was determined by assessing the association between the scale scores and the stages of change. The data of 527 (out of 600) participants (mean age, 41.1 years) were analyzed. Results indicated that the Processes of Change Scale had sufficient internal consistency reliability (Cronbach's alpha: cognitive processes=0.722, behavioral processes=0.803). The processes of change were divided into 2 factors: "consciousness raising

  11. Method matters: Understanding diagnostic reliability in DSM-IV and DSM-5.

    Science.gov (United States)

    Chmielewski, Michael; Clark, Lee Anna; Bagby, R Michael; Watson, David

    2015-08-01

    Diagnostic reliability is essential for the science and practice of psychology, in part because reliability is necessary for validity. Recently, the DSM-5 field trials documented lower diagnostic reliability than past field trials and the general research literature, resulting in substantial criticism of the DSM-5 diagnostic criteria. Rather than indicating specific problems with DSM-5, however, the field trials may have revealed long-standing diagnostic issues that have been hidden due to a reliance on audio/video recordings for estimating reliability. We estimated the reliability of DSM-IV diagnoses using both the standard audio-recording method and the test-retest method used in the DSM-5 field trials, in which different clinicians conduct separate interviews. Psychiatric patients (N = 339) were diagnosed using the SCID-I/P; 218 were diagnosed a second time by an independent interviewer. Diagnostic reliability using the audio-recording method (N = 49) was "good" to "excellent" (M κ = .80) and comparable to the DSM-IV field trials estimates. Reliability using the test-retest method (N = 218) was "poor" to "fair" (M κ = .47) and similar to DSM-5 field-trials' estimates. Despite low test-retest diagnostic reliability, self-reported symptoms were highly stable. Moreover, there was no association between change in self-report and change in diagnostic status. These results demonstrate the influence of method on estimates of diagnostic reliability. (c) 2015 APA, all rights reserved).

  12. Stochastic modeling for reliability shocks, burn-in and heterogeneous populations

    CERN Document Server

    Finkelstein, Maxim

    2013-01-01

    Focusing on shocks modeling, burn-in and heterogeneous populations, Stochastic Modeling for Reliability naturally combines these three topics in the unified stochastic framework and presents numerous practical examples that illustrate recent theoretical findings of the authors.  The populations of manufactured items in industry are usually heterogeneous. However, the conventional reliability analysis is performed under the implicit assumption of homogeneity, which can result in distortion of the corresponding reliability indices and various misconceptions. Stochastic Modeling for Reliability fills this gap and presents the basics and further developments of reliability theory for heterogeneous populations. Specifically, the authors consider burn-in as a method of elimination of ‘weak’ items from heterogeneous populations. The real life objects are operating in a changing environment. One of the ways to model an impact of this environment is via the external shocks occurring in accordance with some stocha...

  13. Test-retest reliability and smallest detectable change of the Bristol Impact of Hypermobility (BIoH) questionnaire.

    Science.gov (United States)

    Palmer, S; Manns, S; Cramp, F; Lewis, R; Clark, E M

    2017-12-01

    The Bristol Impact of Hypermobility (BIoH) questionnaire is a patient-reported outcome measure developed in conjunction with adults with Joint Hypermobility Syndrome (JHS). It has demonstrated strong concurrent validity with the Short Form-36 (SF-36) physical component score but other psychometric properties have yet to be established. This study aimed to determine its test-retest reliability and smallest detectable change (SDC). A test-retest reliability study. Participants were recruited from the Hypermobility Syndromes Association, a patient organisation in the United Kingdom. Recruitment packs were sent to 1080 adults who had given permission to be contacted about research. BIoH and SF-36 questionnaires were administered at baseline and repeated two weeks later. An 11-point global rating of change scale (-5 to +5) was also administered at two weeks. Test-retest analysis and calculation of the SDC was conducted on 'stable' patients (defined as global rating of change -1 to +1). 462 responses were received. 233 patients reported a 'stable' condition and were included in analysis (95% women; mean (SD) age 44.5 (13.9) years; BIoH score 223.6 (54.0)). The BIoH questionnaire demonstrated excellent test-retest reliability (ICC 0.923, 95% CI 0.900-0.940). The SDC was 42 points (equivalent to 19% of the mean baseline score). The SF-36 physical and mental component scores demonstrated poorer test-retest reliability and larger SDCs (as a proportion of the mean baseline scores). The results provide further evidence of the potential of the BIoH questionnaire to underpin research and clinical practice for people with JHS. Copyright © 2017 Elsevier Ltd. All rights reserved.

  14. Projecting the potential evapotranspiration by coupling different formulations and input data reliabilities: The possible uncertainty source for climate change impacts on hydrological regime

    Science.gov (United States)

    Wang, Weiguang; Li, Changni; Xing, Wanqiu; Fu, Jianyu

    2017-12-01

    Representing atmospheric evaporating capability for a hypothetical reference surface, potential evapotranspiration (PET) determines the upper limit of actual evapotranspiration and is an important input to hydrological models. Due that present climate models do not give direct estimates of PET when simulating the hydrological response to future climate change, the PET must be estimated first and is subject to the uncertainty on account of many existing formulae and different input data reliabilities. Using four different PET estimation approaches, i.e., the more physically Penman (PN) equation with less reliable input variables, more empirical radiation-based Priestley-Taylor (PT) equation with relatively dependable downscaled data, the most simply temperature-based Hamon (HM) equation with the most reliable downscaled variable, and downscaling PET directly by the statistical downscaling model, this paper investigated the differences of runoff projection caused by the alternative PET methods by a well calibrated abcd monthly hydrological model. Three catchments, i.e., the Luanhe River Basin, the Source Region of the Yellow River and the Ganjiang River Basin, representing a large climatic diversity were chosen as examples to illustrate this issue. The results indicated that although similar monthly patterns of PET over the period 2021-2050 for each catchment were provided by the four methods, the magnitudes of PET were still slightly different, especially for spring and summer months in the Luanhe River Basin and the Source Region of the Yellow River with relatively dry climate feature. The apparent discrepancy in magnitude of change in future runoff and even the diverse change direction for summer months in the Luanhe River Basin and spring months in the Source Region of the Yellow River indicated that the PET method related uncertainty occurred, especially in the Luanhe River Basin and the Source Region of the Yellow River with smaller aridity index. Moreover, the

  15. Ultrasound assessment for grading structural tendon changes in supraspinatus tendinopathy: an inter-rater reliability study

    DEFF Research Database (Denmark)

    Ingwersen, Kim Gordon; Hjarbæk, John; Eshøj, Henrik

    2016-01-01

    Aim To evaluate the inter-rater reliability of measuring structural changes in the tendon of patients, clinically diagnosed with supraspinatus tendinopathy (cases) and healthy participants (controls), on ultrasound (US) images captured by standardised procedures. Methods A total of 40 participant...

  16. Impact of Climate Change on Natural Snow Reliability, Snowmaking Capacities, and Wind Conditions of Ski Resorts in Northeast Turkey: A Dynamical Downscaling Approach

    Directory of Open Access Journals (Sweden)

    Osman Cenk Demiroglu

    2016-04-01

    Full Text Available Many ski resorts worldwide are going through deteriorating snow cover conditions due to anthropogenic warming trends. As the natural and the artificially supported, i.e., technical, snow reliability of ski resorts diminish, the industry approaches a deadlock. For this reason, impact assessment studies have become vital for understanding vulnerability of ski tourism. This study considers three resorts at one of the rapidly emerging ski destinations, Northeast Turkey, for snow reliability analyses. Initially one global circulation model is dynamically downscaled by using the regional climate model RegCM4.4 for 1971–2000 and 2021–2050 periods along the RCP4.5 greenhouse gas concentration pathway. Next, the projected climate outputs are converted into indicators of natural snow reliability, snowmaking capacity, and wind conditions. The results show an overall decline in the frequencies of naturally snow reliable days and snowmaking capacities between the two periods. Despite the decrease, only the lower altitudes of one ski resort would face the risk of losing natural snow reliability and snowmaking could still compensate for forming the base layer before the critical New Year’s week. On the other hand, adverse high wind conditions improve as to reduce the number of lift closure days at all resorts. Overall, this particular region seems to be relatively resilient against climate change.

  17. Gad1 mRNA as a reliable indicator of altered GABA release from orexigenic neurons in the hypothalamus.

    Science.gov (United States)

    Dicken, Matthew S; Hughes, Alexander R; Hentges, Shane T

    2015-11-01

    The strength of γ-aminobutyric acid (GABA)-mediated inhibitory synaptic input is a principle determinant of neuronal activity. However, because of differences in the number of GABA afferent inputs and the sites of synapses, it is difficult to directly assay for altered GABA transmission between specific cells. The present study tested the hypothesis that the level of mRNA for the GABA synthetic enzyme glutamate decarboxylase (GAD) can provide a reliable proxy for GABA release. This was tested in a mouse hypothalamic circuit important in the regulation of energy balance. Fluorescent in situ hybridization results show that the expression of Gad1 mRNA (encoding the GAD67 enzyme) was increased in hypothalamic neuropeptide Y/agouti-related peptide (NPY/AgRP) neurons after an overnight fast, consistent with the ability of GABA from these neurons to stimulate food intake. Optogenetic studies confirmed that the observed increase in Gad1 mRNA correlated with an increase in the probability of GABA release from NPY/AgRP neurons onto downstream proopiomelanocortin neurons. Likewise, there was an increase in the readily releasable pool of GABA in NPY/AgRP neurons. Selective inhibition of GAD activity in NPY/AgRP neurons decreased GABA release, indicating that GAD67 activity, which is largely dictated by expression level, is a key determinant of GABA release. Altogether, it appears that Gad expression may be a reliable proxy of altered GABAergic transmission. Examining changes in Gad mRNA as a proxy for GABA release may be particularly helpful when the downstream targets are not known or when limited tools exist for detecting GABA release at a particular synapse. © 2015 Federation of European Neuroscience Societies and John Wiley & Sons Ltd.

  18. Usefulness of the Reliable Change Index for psychology and psychiatry in clinical practice: a case report of cognitive-behavioral therapy

    Directory of Open Access Journals (Sweden)

    Danielle de Souza Costa

    2015-10-01

    Full Text Available Objective: The reliable change index (RCI is a simple statistical computation which estimate if changes in two psychometric measures are probably due to measurement error or can be accounted by other factor, as a clinical intervention. Despite its clinical usefulness, the method is underutilized by psychiatrists and psychologists. We consider the use of the RCI in clinical practice by a case report of cognitive-behavioral therapy. Method: a female patient of 40 years old sought cognitive-behavioral therapy due to symptoms of depression. We structured the intervention in 16 sessions and used Beck Depression Inventory II (BDI-II for the assessment of depressive symptoms and answered in each session. Using published data about the BDI-II reliability and its standard deviation, we calculated the RCI before and after the intervention. Results and conclusions: The patient started the treatment with moderate to severe symptoms of depression and showed almost a linear decrease of the symptoms along the sections. Although no reliable change could be associated with the first month of treatment, starting at the second month, we documented a reliable decrease in the depressive symptoms from session 4 to 16. The RCI index it’s a useful method to assess if changes in psychometric measures may represent real change or occur by measurement error.

  19. A Recommended Set of Key Arctic Indicators

    Science.gov (United States)

    Stanitski, D.; Druckenmiller, M.; Fetterer, F. M.; Gerst, M.; Intrieri, J. M.; Kenney, M. A.; Meier, W.; Overland, J. E.; Stroeve, J.; Trainor, S.

    2017-12-01

    The Arctic is an interconnected and environmentally sensitive system of ice, ocean, land, atmosphere, ecosystems, and people. From local to pan-Arctic scales, the area has already undergone major changes in physical and societal systems and will continue at a pace that is greater than twice the global average. Key Arctic indicators can quantify these changes. Indicators serve as the bridge between complex information and policy makers, stakeholders, and the general public, revealing trends and information people need to make important socioeconomic decisions. This presentation evaluates and compiles more than 70 physical, biological, societal and economic indicators into an approachable summary that defines the changing Arctic. We divided indicators into "existing," "in development," "possible," and "aspirational". In preparing a paper on Arctic Indicators for a special issue of the journal Climatic Change, our group established a set of selection criteria to identify indicators to specifically guide decision-makers in their responses to climate change. A goal of the analysis is to select a manageable composite list of recommended indicators based on sustained, reliable data sources with known user communities. The selected list is also based on the development of a conceptual model that identifies components and processes critical to our understanding of the Arctic region. This list of key indicators is designed to inform the plans and priorities of multiple groups such as the U.S. Global Change Research Program (USGCRP), Interagency Arctic Research Policy Committee (IARPC), and the Arctic Council.

  20. FAMILIARISATION AND RELIABILITY OF SPRINT TEST INDICES DURING LABORATORY AND FIELD ASSESSMENT

    Directory of Open Access Journals (Sweden)

    Andrew Galbraith

    2009-12-01

    Full Text Available The aim of the study was to assess the reliability of sprint performance in both field and laboratory conditions. Twenty-one male (mean ± s: 19 ± 1 years, 1.79 ± 0.07 m, 77.6 ± 7.1 kg and seventeen female team sport players (mean ± s: 21 ± 4 years, 1.68 ± 0. 07 m, 62.7 ± 4.7 kg performed a maximal 20-metre sprint running test on eight separate occasions. Four trials were conducted on a non-motorised treadmill in the laboratory; the other four were conducted outdoors on a hard-court training surface with time recorded by single-beam photocells. Trials were conducted in random order with no familiarisation prior to testing. There was a significant difference between times recorded during outdoor field trials (OFT and indoor laboratory trials (ILT using a non-motorised treadmill (3.47 ± 0.53 vs. 6.06 ±1.17s; p < 0.001. The coefficient of variation (CV for time was 2.55-4.22% for OFT and 5.1-7.2% for ILT. During ILT peak force (420.9 ± 87.7N, mean force (147.2 ± 24.7N, peak power (1376.8 ± 451.9W and mean power (514.8 ± 164.4W, and were measured. The CV for all ILT variables was highest during trial 1-2 comparison. The CV (95% confidence interval for the trial 3-4 comparison yielded: 9.4% (7.7-12. 1%, 7.9% (6.4-10.2%, 10.1% (8.2-13.1% and 6.2% (5.1-8.0% for PF, MF, PP and MP and respectively. The results indicate that reliable data can be derived for single maximal sprint measures, using fixed distance protocols. However, significant differences in time/speed over 20-m exist between field and laboratory conditions. This is primarily due to the frictional resistance in the non- motorised treadmill. Measures of force and power during ILT require at least 3 familiarisations to reduce variability in test scores

  1. Distribution system reliability evaluation using credibility theory | Xu ...

    African Journals Online (AJOL)

    In this paper, a hybrid algorithm based on fuzzy simulation and Failure Mode and Effect Analysis (FMEA) is applied to determine fuzzy reliability indices of distribution system. This approach can obtain fuzzy expected values and their variances of reliability indices, and the credibilities of reliability indices meeting specified ...

  2. How reliably can climate change and mitigation policy impacts on electric utilities be assessed?

    International Nuclear Information System (INIS)

    Dowlatabadi, H.; Kopp, R.J.; Palmer, K.; De Witt, D.

    1993-01-01

    Numerous mechanisms link climate change and electric utilities. Electricity generation releases radiatively active trace substances (RATS). Significant changes in atmospheric concentration of RATS can lead to a change in regional and global climate regimes. Mitigation action designed to prevent or limit climate change is possible through curbing emissions. Climate change and related mitigation actions impact on electric utilities. Foresight in electric utility planning requires reliable predictions of how the utilities may be affected in the decades ahead. In this paper the impacts of climate change and mitigation policies are noted, and our ability to assess these is reviewed. To this end a suite of models exploring supply and demand questions have been developed. The overall conclusion of the study is that the demand-side uncertainties dominate other unknowns and need to be better characterized and understood. (author)

  3. The transparency, reliability and utility of tropical rainforest land-use and land-cover change models.

    Science.gov (United States)

    Rosa, Isabel M D; Ahmed, Sadia E; Ewers, Robert M

    2014-06-01

    Land-use and land-cover (LULC) change is one of the largest drivers of biodiversity loss and carbon emissions globally. We use the tropical rainforests of the Amazon, the Congo basin and South-East Asia as a case study to investigate spatial predictive models of LULC change. Current predictions differ in their modelling approaches, are highly variable and often poorly validated. We carried out a quantitative review of 48 modelling methodologies, considering model spatio-temporal scales, inputs, calibration and validation methods. In addition, we requested model outputs from each of the models reviewed and carried out a quantitative assessment of model performance for tropical LULC predictions in the Brazilian Amazon. We highlight existing shortfalls in the discipline and uncover three key points that need addressing to improve the transparency, reliability and utility of tropical LULC change models: (1) a lack of openness with regard to describing and making available the model inputs and model code; (2) the difficulties of conducting appropriate model validations; and (3) the difficulty that users of tropical LULC models face in obtaining the model predictions to help inform their own analyses and policy decisions. We further draw comparisons between tropical LULC change models in the tropics and the modelling approaches and paradigms in other disciplines, and suggest that recent changes in the climate change and species distribution modelling communities may provide a pathway that tropical LULC change modellers may emulate to further improve the discipline. Climate change models have exerted considerable influence over public perceptions of climate change and now impact policy decisions at all political levels. We suggest that tropical LULC change models have an equally high potential to influence public opinion and impact the development of land-use policies based on plausible future scenarios, but, to do that reliably may require further improvements in the

  4. The OMERACT Psoriatic Arthritis Magnetic Resonance Imaging Score (PsAMRIS) is reliable and sensitive to change: results from an OMERACT workshop

    DEFF Research Database (Denmark)

    Bøyesen, Pernille; McQueen, Fiona M; Gandjbakhch, Frédérique

    2011-01-01

    The aim of this multireader exercise was to assess the reliability and sensitivity to change of the psoriatic arthritis magnetic resonance imaging score (PsAMRIS) in PsA patients followed for 1 year.......The aim of this multireader exercise was to assess the reliability and sensitivity to change of the psoriatic arthritis magnetic resonance imaging score (PsAMRIS) in PsA patients followed for 1 year....

  5. Development and validation of a system of assimilation indices: A mixed method approach to understand change in psychotherapy.

    Science.gov (United States)

    Neto, David D; Baptista, Telmo M; Dent-Brown, Kim

    2015-06-01

    Assimilation is an important process in understanding change in psychotherapy. Similar to other psychological processes, assimilation may be traceable in the speech of clients by attending to its signs or indices. In the present research, we aimed to build a system of indices of assimilation. This research follows a mixed method design. The indices were derived through qualitative analysis, using grounded theory. Subsequently, the indices were adjusted quantitatively and applied to 30 single psychotherapy sessions of adult clients with depression and 11 therapists. Forty-two indices were found and grouped into the following five process categories of assimilation: external distress, pain, noticing, decentring and action. The indices showed good inter-rater reliability and internal consistency. Except for noticing, all process categories correlated significantly with each other according to conceptual proximity. The system of indices also showed convergent validity with an existing coding system of assimilation for two process categories. The results suggest that the system of indices is a useful approach for understanding assimilation. The consideration of assimilation in a continuous fashion through sub-processes may help to extend our knowledge of this process and provide a tool for clinical practice. Assimilation is an important process in understanding change in psychotherapy in the sense that it takes into account insight and action-related processes. Clients convey in their speech signs or indices of the assimilation process which can be observed both in the style and content of their utterances. Using these indices, therapists can continuously assess assimilation and use this information in choosing interventions. Limitations: This study follows a cross-sectional design and does not allow consideration of the predictive value of the indices. The outcome of the therapy was not taken into account, which restricts validity considerations to the comparison with

  6. power system reliability in supplying nuclear reactors

    International Nuclear Information System (INIS)

    Gad, M.M.M.

    2007-01-01

    this thesis presents a simple technique for deducing minimal cut set (MCS) from the defined minimal path set (MPS) of generic distribution system and this technique have been used to evaluate the basic reliability indices of Egypt's second research reactor (ETRR-2) electrical distribution network. the alternative system configurations are then studied to evaluate their impact on service reliability. the proposed MCS approach considers both sustained and temporary outage. the temporary outage constitutes an important parameter in characterizing the system reliability indices for critical load point in distribution system. it is also consider the power quality impact on the reliability indices

  7. Estimating changes in unrecorded alcohol consumption in Norway using indicators of harm.

    Science.gov (United States)

    Norström, T

    1998-10-01

    To assess the value of using indicators of alcohol-related harm to estimate changes in unrecorded per capita consumption of alcohol. Unrecorded consumption was estimated from the discrepancy between the observed changes in a number of alcohol-related harm indicators and the changes that would be expected from changes in recorded consumption. The results were compared with estimates of unrecorded consumption from survey data. Four indicators of alcohol-related harm were used: alcohol-related mortality, assaults, drunken driving, and suicide. Estimates of unrecorded consumption from survey data for five different years were used as benchmarks. The best performing indicators were alcohol-related mortality, suicide and assaults, in that order. Combining these indicators yielded a prediction error averaging 12% in comparison with the benchmarks. The method seems worthy of further applications, but it should be regarded as a supplement rather than as a substitute for other approaches.

  8. An indicator of the impact of climatic change on European bird populations.

    Directory of Open Access Journals (Sweden)

    Richard D Gregory

    Full Text Available Rapid climatic change poses a threat to global biodiversity. There is extensive evidence that recent climatic change has affected animal and plant populations, but no indicators exist that summarise impacts over many species and large areas. We use data on long-term population trends of European birds to develop such an indicator. We find a significant relationship between interspecific variation in population trend and the change in potential range extent between the late 20(th and late 21(st centuries, forecasted by climatic envelope models. Our indicator measures divergence in population trend between bird species predicted by climatic envelope models to be favourably affected by climatic change and those adversely affected. The indicator shows a rapid increase in the past twenty years, coinciding with a period of rapid warming.

  9. Indigenous community health and climate change: integrating biophysical and social science indicators

    Science.gov (United States)

    Donatuto, Jamie; Grossman, Eric E.; Konovsky, John; Grossman, Sarah; Campbell, Larry W.

    2014-01-01

    This article describes a pilot study evaluating the sensitivity of Indigenous community health to climate change impacts on Salish Sea shorelines (Washington State, United States and British Columbia, Canada). Current climate change assessments omit key community health concerns, which are vital to successful adaptation plans, particularly for Indigenous communities. Descriptive scaling techniques, employed in facilitated workshops with two Indigenous communities, tested the efficacy of ranking six key indicators of community health in relation to projected impacts to shellfish habitat and shoreline archaeological sites stemming from changes in the biophysical environment. Findings demonstrate that: when shellfish habitat and archaeological resources are impacted, so is Indigenous community health; not all community health indicators are equally impacted; and, the community health indicators of highest concern are not necessarily the same indicators most likely to be impacted. Based on the findings and feedback from community participants, exploratory trials were successful; Indigenous-specific health indicators may be useful to Indigenous communities who are assessing climate change sensitivities and creating adaptation plans.

  10. The Portuguese version of the Outcome Questionnaire (OQ-45): Normative data, reliability, and clinical significance cut-offs scores.

    Science.gov (United States)

    Machado, Paulo P P; Fassnacht, Daniel B

    2015-12-01

    The Outcome Questionnaire (OQ-45) is one of the most extensively used standardized self-report instruments to monitor psychotherapy outcomes. The questionnaire is designed specifically for the assessment of change during psychotherapy treatments. Therefore, it is crucial to provide norms and clinical cut-off values for clinicians and researchers. The current study aims at providing study provides norms, reliability indices, and clinical cut-off values for the Portuguese version of the scale. Data from two large non-clinical samples (high school/university, N = 1,669; community, N = 879) and one clinical sample (n = 201) were used to investigate psychometric properties and derive normative data for all OQ-45 subscales and the total score. Significant and substantial differences were found for all subscales between the clinical and non-clinical sample. The Portuguese version also showed adequate reliabilities (internal consistency, test-retest), which were comparable to the original version. To assess individual clinical change, clinical cut-off values and reliable change indices were calculated allowing clinicians and researchers to monitor and evaluate clients' individual change. The Portuguese version of the OQ-45 is a reliable instrument with comparable Portuguese norms and cut-off scores to those from the original version. This allows clinicians and researchers to use this instrument for evaluating change and outcome in psychotherapy. This study provides norms for non-clinical and clinical Portuguese samples and investigates the reliability (internal consistency and test-retest) of the OQ-45. Cut-off values and reliable change index are provided allowing clinicians to evaluate clinical change and clients' response to treatment, monitoring the quality of mental health care services. These can be used, in routine clinical practice, as benchmarks for treatment progress and to empirically base clinical decisions such as continuation of treatment or considering

  11. French power system reliability report 2008

    International Nuclear Information System (INIS)

    Tesseron, J.M.

    2009-06-01

    / consumption), structure of the system and its design rules, other material measures contributing to operation; 5 - Evolution of measures contributing to reliability in the organizational and human domain: reliability culture, management of the human factor, training, iso 9001 certification - management system, feedback (organisation of feedback, evolution of the ESS scale), performance monitoring, crisis organisation, other organizational measures contributing to reliability; 6 - Lessons drawn from the year's events: lessons drawn from the ESS and from their analysis, feedback other than ESS, noteworthy facts concerning other power systems; 7 - reliability-related indicators: CRE chart of key indicators, RTE internal indicators, indicators for external communication on reliability; 8 - Progress actions underway: actions with the partners concerned (TSOS, users, etc.), main lines of research; 9 - RTE regulation and monitoring system: reliability audit programme, reliability audits; 10 - Conclusion and recommendations

  12. Human factor reliability program

    International Nuclear Information System (INIS)

    Knoblochova, L.

    2017-01-01

    The human factor's reliability program was at Slovenske elektrarne, a.s. (SE) nuclear power plants. introduced as one of the components Initiatives of Excellent Performance in 2011. The initiative's goal was to increase the reliability of both people and facilities, in response to 3 major areas of improvement - Need for improvement of the results, Troubleshooting support, Supporting the achievement of the company's goals. The human agent's reliability program is in practice included: - Tools to prevent human error; - Managerial observation and coaching; - Human factor analysis; -Quick information about the event with a human agent; -Human reliability timeline and performance indicators; - Basic, periodic and extraordinary training in human factor reliability(authors)

  13. A confirmatory study of the Combined Index of Severity of Fibromyalgia (ICAF*: factorial structure, reliability and sensitivity to change

    Directory of Open Access Journals (Sweden)

    Rejas Javier

    2011-06-01

    Full Text Available Abstract Background Fibromyalgia (FM is a complex syndrome that affects many aspects of the patients life and it is very difficult to evaluate in clinical practice. A recent study has developed the Combined Index of Severity of Fibromyalgia (ICAF, an instrument that evaluates diverse aspects of FM and offers five indices: emotional, physical, active coping, passive coping and total. The objective of this study is to confirm the structure of the ICAF, check its test-retest reliability, assess its sensitivity to change, and compare the results obtained in a sample of patients with fibromyalgia with another sample of healthy controls. Methods A total of 232 patients took part in the study, 228 women and 4 men, with a mean age of 47.73 years of age (SD = 8.61 and a time of disease evolution since diagnosis of 4.28 years (SD = 4.03. The patients from the FM group completed the ICAF. Between one and two weeks later, they again attended the clinic and complete the 59 items on the ICAF (retest and immediately afterwards they began treatment (according to daily clinical practice criteria. A sample of healthy subjects was also studied as a control group: 110 people were included (106 women and 4 men with a mean age of 46.01 years of age (SD = 9.35. The study was conducted in Spain. Results The results obtained suggest that the four-factor model obtained in the previous study adequately fits the data obtained in this study. The test-retest reliability and internal consistency were all significant and show a high degree of correlation for all the factors as well as in overall score. With the exception of the passive coping factor, all the other scores, including the overall score, were sensitive to change after the therapeutic intervention. The ICAF scores of the patients with fibromyalgia compared with those of the control group were markedly different. Conclusions The findings suggest that the ICAF is a valid, reliable, sensitive to change instrument with

  14. A confirmatory study of the Combined Index of Severity of Fibromyalgia (ICAF*): factorial structure, reliability and sensitivity to change

    Science.gov (United States)

    2011-01-01

    Background Fibromyalgia (FM) is a complex syndrome that affects many aspects of the patients life and it is very difficult to evaluate in clinical practice. A recent study has developed the Combined Index of Severity of Fibromyalgia (ICAF), an instrument that evaluates diverse aspects of FM and offers five indices: emotional, physical, active coping, passive coping and total. The objective of this study is to confirm the structure of the ICAF, check its test-retest reliability, assess its sensitivity to change, and compare the results obtained in a sample of patients with fibromyalgia with another sample of healthy controls. Methods A total of 232 patients took part in the study, 228 women and 4 men, with a mean age of 47.73 years of age (SD = 8.61) and a time of disease evolution since diagnosis of 4.28 years (SD = 4.03). The patients from the FM group completed the ICAF. Between one and two weeks later, they again attended the clinic and complete the 59 items on the ICAF (retest) and immediately afterwards they began treatment (according to daily clinical practice criteria). A sample of healthy subjects was also studied as a control group: 110 people were included (106 women and 4 men) with a mean age of 46.01 years of age (SD = 9.35). The study was conducted in Spain. Results The results obtained suggest that the four-factor model obtained in the previous study adequately fits the data obtained in this study. The test-retest reliability and internal consistency were all significant and show a high degree of correlation for all the factors as well as in overall score. With the exception of the passive coping factor, all the other scores, including the overall score, were sensitive to change after the therapeutic intervention. The ICAF scores of the patients with fibromyalgia compared with those of the control group were markedly different. Conclusions The findings suggest that the ICAF is a valid, reliable, sensitive to change instrument with the added advantage

  15. Reliability of pulse waveform separation analysis: effects of posture and fasting.

    Science.gov (United States)

    Stoner, Lee; Credeur, Daniel; Fryer, Simon; Faulkner, James; Lambrick, Danielle; Gibbs, Bethany Barone

    2017-03-01

    Oscillometric pulse wave analysis devices enable, with relative simplicity and objectivity, the measurement of central hemodynamic parameters. The important parameters are central blood pressures and indices of arterial wave reflection, including wave separation analysis (backward pressure component Pb and reflection magnitude). This study sought to determine whether the measurement precision (between-day reliability) of Pb and reflection magnitude: exceeds the criterion for acceptable reliability; and is affected by posture (supine, seated) and fasting state. Twenty healthy adults (50% female, 27.9 years, 24.2 kg/m) were tested on six different mornings: 3 days fasted, 3 days nonfasted condition. On each occasion, participants were tested in supine and seated postures. Oscillometric pressure waveforms were recorded on the left upper arm. The criterion intra-class correlation coefficient value of 0.75 was exceeded for Pb (0.76) and reflection magnitude (0.77) when participants were assessed under the combined supine-fasted condition. The intra-class correlation coefficient was lowest for Pb in seated-nonfasted condition (0.57), and lowest for reflection magnitude in the seated-fasted condition (0.56). For Pb, the smallest detectible change that must be exceeded in order for a significant change to occur in an individual was 2.5 mmHg, and for reflection magnitude, the smallest detectable change was 8.5%. Assessments of Pb and reflection magnitude are as follows: exceed the criterion for acceptable reliability; and are most reliable when participants are fasted in a supine position. The demonstrated reliability suggests sufficient precision to detect clinically meaningful changes in reflection magnitude and Pb.

  16. Child nutritional status in contexts of urban poverty: a reliable indicator of family health?

    Directory of Open Access Journals (Sweden)

    Juliana Huergo

    2016-03-01

    Full Text Available This work questions the premise that the nutritional status of children under six years of age is a reliable indicator of family health. To do so, a research strategy based in case studies was carried out, following a qualitative design (participant observation and semistructured interviews using intentional sampling and framed within the interpretivist paradigm. The anthropometric measurements of 20 children under six years of age attending the local Child Care Center in Villa La Tela, Córdoba were evaluated. Nutritional status was understood as an object that includes socially determined biological processes, and was therefore posited analytically as a cross between statistical data and its social determination. As a statistic, child nutritional status is merely descriptive; to assist in the understanding of its social determination, it must be placed in dialectical relationship with the spheres of sociability proposed to analyze the reproduction of health problems.

  17. [Child nutritional status in contexts of urban poverty: a reliable indicator of family health?

    Science.gov (United States)

    Huergo, Juliana; Casabona, Eugenia Lourdes

    2016-03-01

    This work questions the premise that the nutritional status of children under six years of age is a reliable indicator of family health. To do so, a research strategy based in case studies was carried out, following a qualitative design (participant observation and semistructured interviews using intentional sampling) and framed within the interpretivist paradigm. The anthropometric measurements of 20 children under six years of age attending the local Child Care Center in Villa La Tela, Córdoba were evaluated. Nutritional status was understood as an object that includes socially determined biological processes, and was therefore posited analytically as a cross between statistical data and its social determination. As a statistic, child nutritional status is merely descriptive; to assist in the understanding of its social determination, it must be placed in dialectical relationship with the spheres of sociability proposed to analyze the reproduction of health problems.

  18. Simplified Asset Indices to Measure Wealth and Equity in Health Programs: A Reliability and Validity Analysis Using Survey Data From 16 Countries.

    Science.gov (United States)

    Chakraborty, Nirali M; Fry, Kenzo; Behl, Rasika; Longfield, Kim

    2016-03-01

    Social franchising programs in low- and middle-income countries have tried using the standard wealth index, based on the Demographic and Health Survey (DHS) questionnaire, in client exit interviews to assess clients' relative wealth compared with the national wealth distribution to ensure equity in service delivery. The large number of survey questions required to capture the wealth index variables have proved cumbersome for programs. Using an adaptation of the Delphi method, we developed shortened wealth indices and in February 2015 consulted 15 stakeholders in equity measurement. Together, we selected the best of 5 alternative indices, accompanied by 2 measures of agreement (percent agreement and Cohen's kappa statistic) comparing wealth quintile assignment in the new indices to the full DHS index. The panel agreed that reducing the number of assets was more important than standardization across countries because a short index would provide strong indication of client wealth and be easier to collect and use in the field. Additionally, the panel agreed that the simplified index should be highly correlated with the DHS for each country (kappa ≥ 0.75) for both national and urban-specific samples. We then revised indices for 16 countries and selected the minimum number of questions and question options required to achieve a kappa statistic ≥ 0.75 for both national and urban populations. After combining the 5 wealth quintiles into 3 groups, which the expert panel deemed more programmatically meaningful, reliability between the standard DHS wealth index and each of 3 simplified indices was high (median kappa = 0.81, 086, and 0.77, respectively, for index B that included only the common questions from the DHS VI questionnaire, index D that included the common questions plus country-specific questions, and index E that found the shortest list of common and country-specific questions that met the minimum reliability criteria of kappa ≥ 0.75). Index E was the

  19. Simplified Asset Indices to Measure Wealth and Equity in Health Programs: A Reliability and Validity Analysis Using Survey Data From 16 Countries

    Science.gov (United States)

    Chakraborty, Nirali M; Fry, Kenzo; Behl, Rasika; Longfield, Kim

    2016-01-01

    ABSTRACT Background: Social franchising programs in low- and middle-income countries have tried using the standard wealth index, based on the Demographic and Health Survey (DHS) questionnaire, in client exit interviews to assess clients’ relative wealth compared with the national wealth distribution to ensure equity in service delivery. The large number of survey questions required to capture the wealth index variables have proved cumbersome for programs. Methods: Using an adaptation of the Delphi method, we developed shortened wealth indices and in February 2015 consulted 15 stakeholders in equity measurement. Together, we selected the best of 5 alternative indices, accompanied by 2 measures of agreement (percent agreement and Cohen’s kappa statistic) comparing wealth quintile assignment in the new indices to the full DHS index. The panel agreed that reducing the number of assets was more important than standardization across countries because a short index would provide strong indication of client wealth and be easier to collect and use in the field. Additionally, the panel agreed that the simplified index should be highly correlated with the DHS for each country (kappa ≥ 0.75) for both national and urban-specific samples. We then revised indices for 16 countries and selected the minimum number of questions and question options required to achieve a kappa statistic ≥ 0.75 for both national and urban populations. Findings: After combining the 5 wealth quintiles into 3 groups, which the expert panel deemed more programmatically meaningful, reliability between the standard DHS wealth index and each of 3 simplified indices was high (median kappa = 0.81, 086, and 0.77, respectively, for index B that included only the common questions from the DHS VI questionnaire, index D that included the common questions plus country-specific questions, and index E that found the shortest list of common and country-specific questions that met the minimum reliability

  20. Investigating the Intersession Reliability of Dynamic Brain-State Properties.

    Science.gov (United States)

    Smith, Derek M; Zhao, Yrian; Keilholz, Shella D; Schumacher, Eric H

    2018-06-01

    Dynamic functional connectivity metrics have much to offer to the neuroscience of individual differences of cognition. Yet, despite the recent expansion in dynamic connectivity research, limited resources have been devoted to the study of the reliability of these connectivity measures. To address this, resting-state functional magnetic resonance imaging data from 100 Human Connectome Project subjects were compared across 2 scan days. Brain states (i.e., patterns of coactivity across regions) were identified by classifying each time frame using k means clustering. This was done with and without global signal regression (GSR). Multiple gauges of reliability indicated consistency in the brain-state properties across days and GSR attenuated the reliability of the brain states. Changes in the brain-state properties across the course of the scan were investigated as well. The results demonstrate that summary metrics describing the clustering of individual time frames have adequate test/retest reliability, and thus, these patterns of brain activation may hold promise for individual-difference research.

  1. An Adaptive Classification Strategy for Reliable Locomotion Mode Recognition

    Directory of Open Access Journals (Sweden)

    Ming Liu

    2017-09-01

    Full Text Available Algorithms for locomotion mode recognition (LMR based on surface electromyography and mechanical sensors have recently been developed and could be used for the neural control of powered prosthetic legs. However, the variations in input signals, caused by physical changes at the sensor interface and human physiological changes, may threaten the reliability of these algorithms. This study aimed to investigate the effectiveness of applying adaptive pattern classifiers for LMR. Three adaptive classifiers, i.e., entropy-based adaptation (EBA, LearnIng From Testing data (LIFT, and Transductive Support Vector Machine (TSVM, were compared and offline evaluated using data collected from two able-bodied subjects and one transfemoral amputee. The offline analysis indicated that the adaptive classifier could effectively maintain or restore the performance of the LMR algorithm when gradual signal variations occurred. EBA and LIFT were recommended because of their better performance and higher computational efficiency. Finally, the EBA was implemented for real-time human-in-the-loop prosthesis control. The online evaluation showed that the applied EBA effectively adapted to changes in input signals across sessions and yielded more reliable prosthesis control over time, compared with the LMR without adaptation. The developed novel adaptive strategy may further enhance the reliability of neurally-controlled prosthetic legs.

  2. Electrical system design and reliability at Ontario Hydro nuclear generating stations

    Energy Technology Data Exchange (ETDEWEB)

    Royce, C. J. [Ontario Hydro, 700 University Avenue, Toronto, Ontario M5G 1X6 (Canada)

    1986-02-15

    This paper provides an overview of design practice and the predicted and actual reliability of electrical station service Systems at Ontario Nuclear Generating Stations. Operational experience and licensing changes have indicated the desirability of improving reliability in certain instances. For example, the requirement to start large emergency coolant injection pumps resulted in the turbine generator units in a multi-unit station being used as a back-up power supply. Results of reliability analyses are discussed. To mitigate the effects of common mode events Ontario Hydro adopted a 'two group' approach to the design of safety related Systems. This 'two group' approach is reviewed and a single fully environmentally qualified standby power supply is proposed for future use. (author)

  3. Technological advances and changing indications for lumbar puncture in neurological disorders

    NARCIS (Netherlands)

    Costerus, Joost M.; Brouwer, Matthijs C.; van de Beek, Diederik

    2018-01-01

    Technological advances have changed the indications for and the way in which lumbar puncture is done. Suspected CNS infection remains the most common indication for lumbar puncture, but new molecular techniques have broadened CSF analysis indications, such as the determination of neuronal

  4. Reliability of an instrument to determine lower limb comfort in professional football

    Directory of Open Access Journals (Sweden)

    Michael Kinchington

    2010-06-01

    Full Text Available Michael Kinchington1, Kevin Ball1, Geraldine Naughton21School of Human Movement, Recreation and Performance, Victoria University, Melbourne, Australia; 2The Centre of Physical Activity Across the Lifespan (COPAAL, Australian Catholic University, Victoria, AustraliaAims and Objectives: This study extends previous work in the field of injury awareness using a novel lower limb comfort index (LLCI, which was developed to assess comfort in professional football. Participants rated comfort for designated anatomical segments of the lower limb utilizing a seven point Likert scale. The aims of the study were (i to assess the reliability of the LLCI in a competitive football environment (Australian Rules and Rugby League, and (ii to assess whether LLCI measurements were responsive to changes in lower limb comfort over time.Methods and Results: The reliability of the LLCI was observed in two professional football environments: Training Week (mean difference 0.1 point, intra-class correlation coefficient, ICC 0.99 for n = 41 participants; and Match Day (mean difference 0.2 points, ICC 0.97 for n = 22 players. Measurements of lower limb comfort were responsive to changes in comfort over time. Within-player differences were not significant for periods 0–8 hrs (P > 0.05 but, generally, significant for time periods 0–24 hrs (P < 0.05, and significant between 24–96 hrs (P < 0.01. The results indicate that the LLCI was reliable when tested for repeated measures and indicated how the index measures lower limb comfort changes over time.Conclusion: This study shows that the use of a lower limb comfort index, when used in a competitive football environment, is both reliable and responsive to change during both a training week and under match day conditions.Keywords: lower limb comfort, musculoskeletal, football, injury

  5. Reliability, validity, and minimal detectable change of the push-off test scores in assessing upper extremity weight-bearing ability.

    Science.gov (United States)

    Mehta, Saurabh P; George, Hannah R; Goering, Christian A; Shafer, Danielle R; Koester, Alan; Novotny, Steven

    2017-11-01

    Clinical measurement study. The push-off test (POT) was recently conceived and found to be reliable and valid for assessing weight bearing through injured wrist or elbow. However, further research with larger sample can lend credence to the preliminary findings supporting the use of the POT. This study examined the interrater reliability, construct validity, and measurement error for the POT in patients with wrist conditions. Participants with musculoskeletal (MSK) wrist conditions were recruited. The performance on the POT, grip isometric strength of wrist extensors was assessed. The shortened version of the Disabilities of the Arm, Shoulder and Hand and numeric pain rating scale were completed. The intraclass correlation coefficient assessed interrater reliability of the POT. Pearson correlation coefficients (r) examined the concurrent relationships between the POT and other measures. The standard error of measurement and the minimal detectable change at 90% confidence interval were assessed as measurement error and index of true change for the POT. A total of 50 participants with different elbow or wrist conditions (age: 48.1 ± 16.6 years) were included in this study. The results of this study strongly supported the interrater reliability (intraclass correlation coefficient: 0.96 and 0.93 for the affected and unaffected sides, respectively) of the POT in patients with wrist MSK conditions. The POT showed convergent relationships with the grip strength on the injured side (r = 0.89) and the wrist extensor strength (r = 0.7). The POT showed smaller standard error of measurement (1.9 kg). The minimal detectable change at 90% confidence interval for the POT was 4.4 kg for the sample. This study provides additional evidence to support the reliability and validity of the POT. This is the first study that provides the values for the measurement error and true change on the POT scores in patients with wrist MSK conditions. Further research should examine the

  6. Development of key indicators to quantify the health impacts of climate change on Canadians.

    Science.gov (United States)

    Cheng, June J; Berry, Peter

    2013-10-01

    This study aimed at developing a list of key human health indicators for quantifying the health impacts of climate change in Canada. A literature review was conducted in OVID Medline to identify health morbidity and mortality indicators currently used to quantify climate change impacts. Public health frameworks and other studies of climate change indicators were reviewed to identify criteria with which to evaluate the list of proposed key indicators and a rating scale was developed. Total scores for each indicator were calculated based on the rating scale. A total of 77 health indicators were identified from the literature. After evaluation using the chosen criteria, 8 indicators were identified as the best for use. They include excess daily all-cause mortality due to heat, premature deaths due to air pollution (ozone and particulate matter 2.5), preventable deaths from climate change, disability-adjusted life years lost from climate change, daily all-cause mortality, daily non-accidental mortality, West Nile Disease incidence, and Lyme borreliosis incidence. There is need for further data and research related to health effect quantification in the area of climate change.

  7. The reliability and internal consistency of one-shot and flicker change detection for measuring individual differences in visual working memory capacity.

    Science.gov (United States)

    Pailian, Hrag; Halberda, Justin

    2015-04-01

    We investigated the psychometric properties of the one-shot change detection task for estimating visual working memory (VWM) storage capacity-and also introduced and tested an alternative flicker change detection task for estimating these limits. In three experiments, we found that the one-shot whole-display task returns estimates of VWM storage capacity (K) that are unreliable across set sizes-suggesting that the whole-display task is measuring different things at different set sizes. In two additional experiments, we found that the one-shot single-probe variant shows improvements in the reliability and consistency of K estimates. In another additional experiment, we found that a one-shot whole-display-with-click task (requiring target localization) also showed improvements in reliability and consistency. The latter results suggest that the one-shot task can return reliable and consistent estimates of VWM storage capacity (K), and they highlight the possibility that the requirement to localize the changed target is what engenders this enhancement. Through a final series of four experiments, we introduced and tested an alternative flicker change detection method that also requires the observer to localize the changing target and that generates, from response times, an estimate of VWM storage capacity (K). We found that estimates of K from the flicker task correlated with estimates from the traditional one-shot task and also had high reliability and consistency. We highlight the flicker method's ability to estimate executive functions as well as VWM storage capacity, and discuss the potential for measuring multiple abilities with the one-shot and flicker tasks.

  8. Prediction of safety critical software operational reliability from test reliability using testing environment factors

    International Nuclear Information System (INIS)

    Jung, Hoan Sung; Seong, Poong Hyun

    1999-01-01

    It has been a critical issue to predict the safety critical software reliability in nuclear engineering area. For many years, many researches have focused on the quantification of software reliability and there have been many models developed to quantify software reliability. Most software reliability models estimate the reliability with the failure data collected during the test assuming that the test environments well represent the operation profile. User's interest is however on the operational reliability rather than on the test reliability. The experiences show that the operational reliability is higher than the test reliability. With the assumption that the difference in reliability results from the change of environment, from testing to operation, testing environment factors comprising the aging factor and the coverage factor are developed in this paper and used to predict the ultimate operational reliability with the failure data in testing phase. It is by incorporating test environments applied beyond the operational profile into testing environment factors. The application results show that the proposed method can estimate the operational reliability accurately. (Author). 14 refs., 1 tab., 1 fig

  9. Computation of reliable textural indices from multimodal brain MRI: suggestions based on a study of patients with diffuse intrinsic pontine glioma

    Science.gov (United States)

    Goya-Outi, Jessica; Orlhac, Fanny; Calmon, Raphael; Alentorn, Agusti; Nioche, Christophe; Philippe, Cathy; Puget, Stéphanie; Boddaert, Nathalie; Buvat, Irène; Grill, Jacques; Frouin, Vincent; Frouin, Frederique

    2018-05-01

    Few methodological studies regarding widely used textural indices robustness in MRI have been reported. In this context, this study aims to propose some rules to compute reliable textural indices from multimodal 3D brain MRI. Diagnosis and post-biopsy MR scans including T1, post-contrast T1, T2 and FLAIR images from thirty children with diffuse intrinsic pontine glioma (DIPG) were considered. The hybrid white stripe method was adapted to standardize MR intensities. Sixty textural indices were then computed for each modality in different regions of interest (ROI), including tumor and white matter (WM). Three types of intensity binning were compared : constant bin width and relative bounds; constant number of bins and relative bounds; constant number of bins and absolute bounds. The impact of the volume of the region was also tested within the WM. First, the mean Hellinger distance between patient-based intensity distributions decreased by a factor greater than 10 in WM and greater than 2.5 in gray matter after standardization. Regarding the binning strategy, the ranking of patients was highly correlated for 188/240 features when comparing with , but for only 20 when comparing with , and nine when comparing with . Furthermore, when using or texture indices reflected tumor heterogeneity as assessed visually by experts. Last, 41 features presented statistically significant differences between contralateral WM regions when ROI size slightly varies across patients, and none when using ROI of the same size. For regions with similar size, 224 features were significantly different between WM and tumor. Valuable information from texture indices can be biased by methodological choices. Recommendations are to standardize intensities in MR brain volumes, to use intensity binning with constant bin width, and to define regions with the same volumes to get reliable textural indices.

  10. The use of adaptable automation: Effects of extended skill lay-off and changes in system reliability.

    Science.gov (United States)

    Sauer, Juergen; Chavaillaz, Alain

    2017-01-01

    This experiment aimed to examine how skill lay-off and system reliability would affect operator behaviour in a simulated work environment under wide-range and large-choice adaptable automation comprising six different levels. Twenty-four participants were tested twice during a 2-hr testing session, with the second session taking place 8 months after the first. In the middle of the second testing session, system reliability changed. The results showed that after the retention interval trust increased and self-confidence decreased. Complacency was unaffected by the lay-off period. Diagnostic speed slowed down after the retention interval but diagnostic accuracy was maintained. No difference between experimental conditions was found for automation management behaviour (i.e. level of automation chosen and frequency of switching between levels). There were few effects of system reliability. Overall, the findings showed that subjective measures were more sensitive to the impact of skill lay-off than objective behavioural measures. Copyright © 2016 Elsevier Ltd. All rights reserved.

  11. Overall Key Performance Indicator to Optimizing Operation of High-Pressure Homogenizers for a Reliable Quantification of Intracellular Components in Pichia pastoris.

    Science.gov (United States)

    Garcia-Ortega, Xavier; Reyes, Cecilia; Montesinos, José Luis; Valero, Francisco

    2015-01-01

    The most commonly used cell disruption procedures may present lack of reproducibility, which introduces significant errors in the quantification of intracellular components. In this work, an approach consisting in the definition of an overall key performance indicator (KPI) was implemented for a lab scale high-pressure homogenizer (HPH) in order to determine the disruption settings that allow the reliable quantification of a wide sort of intracellular components. This innovative KPI was based on the combination of three independent reporting indicators: decrease of absorbance, release of total protein, and release of alkaline phosphatase activity. The yeast Pichia pastoris growing on methanol was selected as model microorganism due to it presents an important widening of the cell wall needing more severe methods and operating conditions than Escherichia coli and Saccharomyces cerevisiae. From the outcome of the reporting indicators, the cell disruption efficiency achieved using HPH was about fourfold higher than other lab standard cell disruption methodologies, such bead milling cell permeabilization. This approach was also applied to a pilot plant scale HPH validating the methodology in a scale-up of the disruption process. This innovative non-complex approach developed to evaluate the efficacy of a disruption procedure or equipment can be easily applied to optimize the most common disruption processes, in order to reach not only reliable quantification but also recovery of intracellular components from cell factories of interest.

  12. Development of an indicator to monitor mediterranean wetlands.

    Science.gov (United States)

    Sanchez, Antonio; Abdul Malak, Dania; Guelmami, Anis; Perennou, Christian

    2015-01-01

    Wetlands are sensitive ecosystems that are increasingly subjected to threats from anthropogenic factors. In the last decades, coastal Mediterranean wetlands have been suffering considerable pressures from land use change, intensification of urban growth, increasing tourism infrastructure and intensification of agricultural practices. Remote sensing (RS) and Geographic Information Systems (GIS) techniques are efficient tools that can support monitoring Mediterranean coastal wetlands on large scales and over long periods of time. The study aims at developing a wetland indicator to support monitoring Mediterranean coastal wetlands using these techniques. The indicator makes use of multi-temporal Landsat images, land use reference layers, a 50m numerical model of the territory (NMT) and Corine Land Cover (CLC) for the identification and mapping of wetlands. The approach combines supervised image classification techniques making use of vegetation indices and decision tree analysis to identify the surface covered by wetlands at a given date. A validation process is put in place to compare outcomes with existing local wetland inventories to check the results reliability. The indicator´s results demonstrate an improvement in the level of precision of change detection methods achieved by traditional tools providing reliability up to 95% in main wetland areas. The results confirm that the use of RS techniques improves the precision of wetland detection compared to the use of CLC for wetland monitoring and stress the strong relation between the level of wetland detection and the nature of the wetland areas and the monitoring scale considered.

  13. Mountains as early warning indicators of climate change

    Science.gov (United States)

    Williams, M. W.

    2015-12-01

    The panoramic splendor and complexity of mountain environments have inspired and challenged humans for centuries. These areas have been variously perceived as physical structures to be conquered, as sites of spiritual inspiration, and as some of the last untamed natural places on Earth. In our time, the perception that "mountains are forever" may provide solace to those seeking stability in a rapidly changing world. However, changes in the hydrology and in the abundance and species composition of the native flora and fauna of mountain ecosystems are potential bellwethers of global change, because these systems have a propensity to amplify environmental changes within specific portions of this landscape. Mountain areas are thus sentinels of climate change. We are seeing effects today in case histories I present from the Himalaya's, Andes, Alps, and Rocky Mountains. Furthermore, these ecosystem changes are occurring in mountain areas before they occur in downstream ecosystems. Thus, mountains are early warning indicators of perturbations such as climate change. The sensitivity of mountain ecosystems begs for enhanced protection and worldwide protection. Our understanding of the processes that control mountain ecosystems—climate interactions, snowmelt runoff, biotic diversity, nutrient cycling—is much less developed compared to downstream ecosystems where human habitation and development has resulted in large investments in scientific knowledge to sustain health and agriculture. To address these deficiencies, I propose the formation of an international mountain research consortium.

  14. Building and integrating reliability models in a Reliability-Centered-Maintenance approach

    International Nuclear Information System (INIS)

    Verite, B.; Villain, B.; Venturini, V.; Hugonnard, S.; Bryla, P.

    1998-03-01

    Electricite de France (EDF) has recently developed its OMF-Structures method, designed to optimize preventive maintenance of passive structures such as pipes and support, based on risk. In particular, reliability performances of components need to be determined; it is a two-step process, consisting of a qualitative sort followed by a quantitative evaluation, involving two types of models. Initially, degradation models are widely used to exclude some components from the field of preventive maintenance. The reliability of the remaining components is then evaluated by means of quantitative reliability models. The results are then included in a risk indicator that is used to directly optimize preventive maintenance tasks. (author)

  15. Development of key indicators to quantify the health impacts of climate change on Canadians

    OpenAIRE

    Cheng, June J.; Berry, Peter

    2013-01-01

    Objectives This study aimed at developing a list of key human health indicators for quantifying the health impacts of climate change in Canada. Methods A literature review was conducted in OVID Medline to identify health morbidity and mortality indicators currently used to quantify climate change impacts. Public health frameworks and other studies of climate change indicators were reviewed to identify criteria with which to evaluate the list of proposed key indicators and a rating scale was d...

  16. Test-retest reliability of cognitive EEG

    Science.gov (United States)

    McEvoy, L. K.; Smith, M. E.; Gevins, A.

    2000-01-01

    OBJECTIVE: Task-related EEG is sensitive to changes in cognitive state produced by increased task difficulty and by transient impairment. If task-related EEG has high test-retest reliability, it could be used as part of a clinical test to assess changes in cognitive function. The aim of this study was to determine the reliability of the EEG recorded during the performance of a working memory (WM) task and a psychomotor vigilance task (PVT). METHODS: EEG was recorded while subjects rested quietly and while they performed the tasks. Within session (test-retest interval of approximately 1 h) and between session (test-retest interval of approximately 7 days) reliability was calculated for four EEG components: frontal midline theta at Fz, posterior theta at Pz, and slow and fast alpha at Pz. RESULTS: Task-related EEG was highly reliable within and between sessions (r0.9 for all components in WM task, and r0.8 for all components in the PVT). Resting EEG also showed high reliability, although the magnitude of the correlation was somewhat smaller than that of the task-related EEG (r0.7 for all 4 components). CONCLUSIONS: These results suggest that under appropriate conditions, task-related EEG has sufficient retest reliability for use in assessing clinical changes in cognitive status.

  17. Does Changing Examiner Stations During UK Postgraduate Surgery Objective Structured Clinical Examinations Influence Examination Reliability and Candidates' Scores?

    Science.gov (United States)

    Brennan, Peter A; Croke, David T; Reed, Malcolm; Smith, Lee; Munro, Euan; Foulkes, John; Arnett, Richard

    2016-01-01

    Objective structured clinical examinations (OSCE) are widely used for summative assessment in surgery. Despite standardizing these as much as possible, variation, including examiner scoring, can occur which may affect reliability. In study of a high-stakes UK postgraduate surgical OSCE, we investigated whether examiners changing stations once during a long examining day affected marking, reliability, and overall candidates' scores compared with examiners who examined the same scenario all day. An observational study of 18,262 examiner-candidate interactions from the UK Membership of the Royal College of Surgeons examination was carried at 3 Surgical Colleges across the United Kingdom. Scores between examiners were compared using analysis of variance. Examination reliability was assessed with Cronbach's alpha, and the comparative distribution of total candidates' scores for each day was evaluated using t-tests of unit-weighted z scores. A significant difference was found in absolute scores differences awarded in the morning and afternoon sessions between examiners who changed stations at lunchtime and those who did not (p design and examiner experience in surgical OSCEs and beyond. Copyright © 2016 Association of Program Directors in Surgery. Published by Elsevier Inc. All rights reserved.

  18. Single-leg lateral, horizontal, and vertical jump assessment: reliability, interrelationships, and ability to predict sprint and change-of-direction performance.

    Science.gov (United States)

    Meylan, Cesar; McMaster, Travis; Cronin, John; Mohammad, Nur Ikhwan; Rogers, Cailyn; Deklerk, Melissa

    2009-07-01

    The purposes of this study were to determine the reliability of unilateral vertical, horizontal, and lateral countermovement jump assessments, the interrelationship between these tests, and their usefulness as predictors of sprint (10 m) and change-of-direction (COD) performance for 80 men and women physical education students. Jump performance was assessed on a contact mat and sprint, and COD performances were assessed using timing lights. With regard to the reliability statistics, the largest coefficient of variation (CV) was observed for the vertical jump (CV = 6.7-7.2%) of both genders, whereas the sprint and COD assessments had smallest variability (CV = 0.8 to 2.8%). All intraclass correlation coefficients (ICC) were greater than 0.85, except for the men's COD assessment with the alternate leg. The shared variance between the single-leg vertical, horizontal, and lateral jumps for men and women was less than 50%, indicating that the jumps are relatively independent of one another and represent different leg strength/power qualities. The ability of the jumps to predict sprint and COD performance was limited (R2 < 43%). It would seem that the ability to change direction with 1 leg is relatively independent of a COD with the other leg, especially in the women (R < 30%) of this study. However, if 1 jump assessment were selected to predict sprint and COD performance in a test battery, the single-leg horizontal countermovement jump would seem the logical choice, given the results of this study. Many of the findings in this study have interesting diagnostic and training implications for the strength and conditioning coach.

  19. Reliability of construction materials

    International Nuclear Information System (INIS)

    Merz, H.

    1976-01-01

    One can also speak of reliability with respect to materials. While for reliability of components the MTBF (mean time between failures) is regarded as the main criterium, this is replaced with regard to materials by possible failure mechanisms like physical/chemical reaction mechanisms, disturbances of physical or chemical equilibrium, or other interactions or changes of system. The main tasks of the reliability analysis of materials therefore is the prediction of the various failure reasons, the identification of interactions, and the development of nondestructive testing methods. (RW) [de

  20. Indicators of climate change in Idaho: An assessment framework for coupling biophysical change and social perception

    Science.gov (United States)

    Climate change is well documented at the global scale, but local and regional changes are not as well understood. Finer, local-to-regional scale information is needed for creating specific, place-based planning and adaption efforts. Here we detail the development of an indicator-focused climate chan...

  1. Impact of climate change in Switzerland on socioeconomic snow indices

    Science.gov (United States)

    Schmucki, Edgar; Marty, Christoph; Fierz, Charles; Weingartner, Rolf; Lehning, Michael

    2017-02-01

    Snow is a key element for many socioeconomic activities in mountainous regions. Due to the sensitivity of the snow cover to variations of temperature and precipitation, major changes caused by climate change are expected to happen. We analyze the evolution of some key snow indices under future climatic conditions. Ten downscaled and postprocessed climate scenarios from the ENSEMBLES database have been used to feed the physics-based snow model SNOWPACK. The projected snow cover has been calculated for 11 stations representing the diverse climates found in Switzerland. For the first time, such a setup is used to reveal changes in frequently applied snow indices and their implications on various socioeconomic sectors. Toward the end of the twenty-first century, a continuous snow cover is likely only guaranteed at high elevations above 2000 m a.s.l., whereas at mid elevations (1000-1700 m a.s.l.), roughly 50 % of all winters might be characterized by an ephemeral snow cover. Low elevations (below 500 m a.s.l.) are projected to experience only 2 days with snowfall per year and show the strongest relative reductions in mean winter snow depth of around 90 %. The range of the mean relative reductions of the snow indices is dominated by uncertainties from different GCM-RCM projections and amounts to approximately 30 %. Despite these uncertainties, all snow indices show a clear decrease in all scenario periods and the relative reductions increase toward lower elevations. These strong reductions can serve as a basis for policy makers in the fields of tourism, ecology, and hydropower.

  2. Distribution System Reliability Analysis for Smart Grid Applications

    Science.gov (United States)

    Aljohani, Tawfiq Masad

    Reliability of power systems is a key aspect in modern power system planning, design, and operation. The ascendance of the smart grid concept has provided high hopes of developing an intelligent network that is capable of being a self-healing grid, offering the ability to overcome the interruption problems that face the utility and cost it tens of millions in repair and loss. To address its reliability concerns, the power utilities and interested parties have spent extensive amount of time and effort to analyze and study the reliability of the generation and transmission sectors of the power grid. Only recently has attention shifted to be focused on improving the reliability of the distribution network, the connection joint between the power providers and the consumers where most of the electricity problems occur. In this work, we will examine the effect of the smart grid applications in improving the reliability of the power distribution networks. The test system used in conducting this thesis is the IEEE 34 node test feeder, released in 2003 by the Distribution System Analysis Subcommittee of the IEEE Power Engineering Society. The objective is to analyze the feeder for the optimal placement of the automatic switching devices and quantify their proper installation based on the performance of the distribution system. The measures will be the changes in the reliability system indices including SAIDI, SAIFI, and EUE. The goal is to design and simulate the effect of the installation of the Distributed Generators (DGs) on the utility's distribution system and measure the potential improvement of its reliability. The software used in this work is DISREL, which is intelligent power distribution software that is developed by General Reliability Co.

  3. Reliability models for Space Station power system

    Science.gov (United States)

    Singh, C.; Patton, A. D.; Kim, Y.; Wagner, H.

    1987-01-01

    This paper presents a methodology for the reliability evaluation of Space Station power system. The two options considered are the photovoltaic system and the solar dynamic system. Reliability models for both of these options are described along with the methodology for calculating the reliability indices.

  4. Relative and Absolute Reliability of Timed Up and Go Test in Community Dwelling Older Adult and Healthy Young People

    Directory of Open Access Journals (Sweden)

    Farhad Azadi

    2014-01-01

    Full Text Available Objectives: Relative and absolute reliability are psychometric properties of the test that many clinical decisions are based on them. In many cases, only relative reliability takes into consideration while the absolute reliability is also very important. Methods & Materials: Eleven community-dwelling older adults aged 65 years and older (69.64±3.58 and 20 healthy young in the age range 20 to 35 years (28.80±4.15 using three versions of Timed Up and Go test were evaluated twice with an interval of 2 to 5 days. Results: Generally, the non-homogeneity of the study population was stratified to increase the Intra-class Correlation Coefficient (ICC this coefficient in elderly people is greater than young people and with a secondary task is reduced. In This study, absolute reliability indices using different data sources and equations lead to in more or less similar results. At general, in test–retest situations, the elderly more than the young people must be changed to be interpreted as a real change, not random. The random error contribution is slightly greater in elderly than young and with a secondary task is increased.It seems, heterogeneity leads to moderation in absolute reliability indices. Conclusion: In relative reliability studies, researchers and clinicians should pay attention to factors such as homogeneity of population and etc. As well as, absolute reliability beside relative reliability is needed and necessary in clinical decision making.

  5. Reliability of wind turbine subassemblies

    NARCIS (Netherlands)

    Spinato, F.; Tavner, P.J.; Bussel, van G.J.W.; Koutoulakos, E.

    2009-01-01

    We have investigated the reliability of more than 6000 modern onshore wind turbines and their subassemblies in Denmark and Germany over 11 years and particularly changes in reliability of generators, gearboxes and converters in a subset of 650 turbines in Schleswig Holstein, Germany. We first start

  6. Optimal Reliability-Based Code Calibration

    DEFF Research Database (Denmark)

    Sørensen, John Dalsgaard; Kroon, I. B.; Faber, Michael Havbro

    1994-01-01

    Calibration of partial safety factors is considered in general, including classes of structures where no code exists beforehand. The partial safety factors are determined such that the difference between the reliability for the different structures in the class considered and a target reliability...... level is minimized. Code calibration on a decision theoretical basis is also considered and it is shown how target reliability indices can be calibrated. Results from code calibration for rubble mound breakwater designs are shown....

  7. Reliability and validity of the Dutch version of the Readiness to Change Questionnaire.

    Science.gov (United States)

    Defuentes-Merillas, L; Dejong, C A J; Schippers, G M

    2002-01-01

    The aim of the present study was to evaluate the psychometric properties of the Dutch version of the Readiness to Change Questionnaire (RCQ-D). The subjects were 246 excessive drinkers admitted to an addiction treatment centre and 54 offenders convicted of an alcohol-related crime in The Netherlands. The factor structure of the RCQ-D for the two samples combined was found to be consistent with the three-factor structure established for the original RCQ. The reliability of the items for each scale was found to be satisfactory. Allocated stage of change showed significant differences between the different subsamples. As expected, the scale scores for adjacent stages of change showed significantly higher inter-correlations than the scale scores for non-adjacent stages. Additionally, the negatively formulated items from the pre-contemplation scale were reformulated positively and their internal consistency tested among the offender sample. The positively formulated pre-contemplation items showed a higher alpha value than the negatively formulated items. We therefore suggest that the positively formulated items should replace the negatively formulated ones.

  8. On Bayesian System Reliability Analysis

    Energy Technology Data Exchange (ETDEWEB)

    Soerensen Ringi, M

    1995-05-01

    The view taken in this thesis is that reliability, the probability that a system will perform a required function for a stated period of time, depends on a person`s state of knowledge. Reliability changes as this state of knowledge changes, i.e. when new relevant information becomes available. Most existing models for system reliability prediction are developed in a classical framework of probability theory and they overlook some information that is always present. Probability is just an analytical tool to handle uncertainty, based on judgement and subjective opinions. It is argued that the Bayesian approach gives a much more comprehensive understanding of the foundations of probability than the so called frequentistic school. A new model for system reliability prediction is given in two papers. The model encloses the fact that component failures are dependent because of a shared operational environment. The suggested model also naturally permits learning from failure data of similar components in non identical environments. 85 refs.

  9. On Bayesian System Reliability Analysis

    International Nuclear Information System (INIS)

    Soerensen Ringi, M.

    1995-01-01

    The view taken in this thesis is that reliability, the probability that a system will perform a required function for a stated period of time, depends on a person's state of knowledge. Reliability changes as this state of knowledge changes, i.e. when new relevant information becomes available. Most existing models for system reliability prediction are developed in a classical framework of probability theory and they overlook some information that is always present. Probability is just an analytical tool to handle uncertainty, based on judgement and subjective opinions. It is argued that the Bayesian approach gives a much more comprehensive understanding of the foundations of probability than the so called frequentistic school. A new model for system reliability prediction is given in two papers. The model encloses the fact that component failures are dependent because of a shared operational environment. The suggested model also naturally permits learning from failure data of similar components in non identical environments. 85 refs

  10. Comparison between visual half-field performance and cerebral blood flow changes as indicators of language dominance.

    Science.gov (United States)

    Krach, S; Chen, L M; Hartje, W

    2006-03-01

    The determination of hemispheric language dominance (HLD) can be accomplished in two ways. One approach relies on hemispheric differences in cerebral blood flow velocity (CBFV) changes during language activity, while the other approach makes use of performance differences between the left and right visual field when verbal stimuli are presented in a tachistoscopic visual field paradigm. Since both methodologically different approaches claim to assess functional HLD, it seems plausible to expect that the respective laterality indices (LI) would correspond. To test this expectation we measured language lateralisation in 58 healthy right-handed, left-handed, and ambidextrous subjects with both approaches. CBFV changes were recorded with functional transcranial Doppler sonography (fTCD). We applied a lexical decision task with bilateral visual field presentation of abstract nouns and, in addition, a task of mental word generation. In the lexical decision task, a highly significant right visual field advantage was observed for number of correct responses and reaction times, while at the same time and contrary to expectation the increase of CBFV was significantly higher in the right than left hemisphere. During mental word generation, the acceleration of CBF was significantly higher in the left hemisphere. A comparison between individual LI derived from CBF measurement during mental word generation and from visual field performances in the lexical decision task showed a moderate correspondence in classifying the subjects' HLD. However, the correlation between the corresponding individual LI was surprisingly low and not significant. The results are discussed with regard to the issue of a limited reliability of behavioural LI on the one hand and the possibility of a fundamental difference between the behavioural and the physiological indicators of laterality on the other hand.

  11. An Impact of Thermodynamic Processes in Human Bodies on Performance Reliability of Individuals

    Directory of Open Access Journals (Sweden)

    Smalko Zbigniew

    2015-01-01

    Full Text Available The article presents the problem of the influence of thermodynamic factors on human fallibility in different zones of thermal discomfort. Describes the processes of energy in the human body. Been given a formal description of the energy balance of the human body thermoregulation. Pointed to human reactions to temperature changes of internal and external environment, including reactions associated with exercise. The methodology to estimate and determine the reliability of indicators of human basal acting in different zones of thermal discomfort. The significant effect of thermodynamic factors on the reliability and security ofperson.

  12. Fine roots and ectomycorrhizas as indicators of environmental change

    Czech Academy of Sciences Publication Activity Database

    Cudlín, Pavel; Kieliszewska-Rokicka, B.; Rudawska, M.; Grebenc, T.; Alberton, O.; Lehto, T.; Bakker, M. R.; Borja, I.; Konopka, B.; Leski, T.; Kraigher, H.; Kuyper, T. W.

    2007-01-01

    Roč. 141, č. 3 (2007), s. 406-425 ISSN 1126-3504 R&D Projects: GA MŠk OC E38.001 Institutional research plan: CEZ:AV0Z60870520 Keywords : Environmental change * indicators * meta-analysis * temperate and boreal zones * woody plants Subject RIV: EH - Ecology, Behaviour Impact factor: 0.750, year: 2007

  13. Safety, reliability and worker satisfaction during organizational change

    NARCIS (Netherlands)

    Zwetsloot, G.I.J.M.; Drupsteen, L.; Vroome, E.M.M. de

    2014-01-01

    The research presented in this paper was carried out in four process industry plants in the Netherlands, to identify factors that have the potential to increase safety and reliability while maintaining or improving job satisfaction. The data used were gathered as part of broader trajectories in

  14. Climate Change Impacts and Responses: Societal Indicators for the National Climate Assessment

    Science.gov (United States)

    Kenney, Melissa A.; Chen, Robert S.; Maldonado, Julie; Quattrochi, Dale

    2011-01-01

    The Climate Change Impacts and Responses: Societal Indicators for the National Climate Assessment workshop, sponsored by the National Aeronautics and Space Administration (NASA) for the National Climate Assessment (NCA), was held on April 28-29, 2011 at The Madison Hotel in Washington, DC. A group of 56 experts (see list in Appendix B) convened to share their experiences. Participants brought to bear a wide range of disciplinary expertise in the social and natural sciences, sector experience, and knowledge about developing and implementing indicators for a range of purposes. Participants included representatives from federal and state government, non-governmental organizations, tribes, universities, and communities. The purpose of the workshop was to assist the NCA in developing a strategic framework for climate-related physical, ecological, and socioeconomic indicators that can be easily communicated with the U.S. population and that will support monitoring, assessment, prediction, evaluation, and decision-making. The NCA indicators are envisioned as a relatively small number of policy-relevant integrated indicators designed to provide a consistent, objective, and transparent overview of major variations in climate impacts, vulnerabilities, adaptation, and mitigation activities across sectors, regions, and timeframes. The workshop participants were asked to provide input on a number of topics, including: (1) categories of societal indicators for the NCA; (2) alternative approaches to constructing indicators and the better approaches for NCA to consider; (3) specific requirements and criteria for implementing the indicators; and (4) sources of data for and creators of such indicators. Socioeconomic indicators could include demographic, cultural, behavioral, economic, public health, and policy components relevant to impacts, vulnerabilities, and adaptation to climate change as well as both proactive and reactive responses to climate change. Participants provided

  15. Spot market natural gas strategies and reliability dealing with changing industry conditions

    International Nuclear Information System (INIS)

    McClure, D.C.

    1992-01-01

    Many in the energy industry thought the natural gas buying game had finally settled down to a predictable pattern in the 90's. After a tumultuous decade in the 80's they are ready to turn their attention to new challenges such as electricity wheeling and cogeneration. They were wrong. There is plenty of change left in the natural gas industry for the rest of the century. This growth will dramatically increase the number of options available to Energy Buyers, giving them new flexibility to design programs that meet goals for cost reduction, supply reliability, and administrative effort. However, with new options also come the responsibility for choices. Energy Managers of well designed gas programs will make these choices after careful consideration of the pro's and con's of each option. In short, the effective Buyer will develop a natural gas strategy. This report will begin by reviewing the basic types of change occurring in the industry, and then discuss some of the varied strategy options available to the Energy Buyer

  16. Bulk electric system reliability evaluation incorporating wind power and demand side management

    Science.gov (United States)

    Huang, Dange

    Electric power systems are experiencing dramatic changes with respect to structure, operation and regulation and are facing increasing pressure due to environmental and societal constraints. Bulk electric system reliability is an important consideration in power system planning, design and operation particularly in the new competitive environment. A wide range of methods have been developed to perform bulk electric system reliability evaluation. Theoretically, sequential Monte Carlo simulation can include all aspects and contingencies in a power system and can be used to produce an informative set of reliability indices. It has become a practical and viable tool for large system reliability assessment technique due to the development of computing power and is used in the studies described in this thesis. The well-being approach used in this research provides the opportunity to integrate an accepted deterministic criterion into a probabilistic framework. This research work includes the investigation of important factors that impact bulk electric system adequacy evaluation and security constrained adequacy assessment using the well-being analysis framework. Load forecast uncertainty is an important consideration in an electrical power system. This research includes load forecast uncertainty considerations in bulk electric system reliability assessment and the effects on system, load point and well-being indices and reliability index probability distributions are examined. There has been increasing worldwide interest in the utilization of wind power as a renewable energy source over the last two decades due to enhanced public awareness of the environment. Increasing penetration of wind power has significant impacts on power system reliability, and security analyses become more uncertain due to the unpredictable nature of wind power. The effects of wind power additions in generating and bulk electric system reliability assessment considering site wind speed

  17. Current status of biological indicators to detect and quantify previous exposures to radiation. Biological Indicators Working Group

    International Nuclear Information System (INIS)

    Lushbaugh, C.; Eisele, G.; Burr, W. Jr.; Hubner, K.; Wachholz, B.

    1991-01-01

    Hematologic changes following whole-body exposure to gamma or x-ray radiation have been used to estimate dose. The usefulness of this biological indicator is limited because of the recovery of these cells with time, thus making it unsuitable for estimation of dose years after exposure. The same is true for spermatogenic indicators; recovery and restoration of sperm numbers and fertility makes this biological indicator impractical for assessing radiation dose decades after radiation exposure. As noted in the text of the report, immunological concepts are in a state of rapid development, and it is possible that improved methods for applying immunologic procedures as biological indicators of radiation may be developed in the future. However, at the time, immunological indicators are not useful, even in an early time period, for quantitating radiation dose after total-body irradiation. A semiquantitative effect is observable in the early phase after total-body irradiation over a period of days to weeks, but there is little data available to indicate whether any of the immunological parameters can be indicative of a dose when the test is applied several years after radiation exposure. More detailed information regarding immunological indicators for estimating irradiation dose has been summarized elsewhere (Wasserman 1986). There is good agreement that ionizing radiation causes biochemical changes in the body; however, attempts to apply these changes to provide a reliable biological dosimetry system have not been particularly successful. The status of this research has been summarized by Gerber (1986). One of the difficulties has been the problem of establishing clear dose-effect relationships in humans. The lack of specificity in the response for radiation is another problem

  18. Reliability of maximal isometric knee strength testing with modified hand-held dynamometry in patients awaiting total knee arthroplasty: useful in research and individual patient settings? A reliability study

    Directory of Open Access Journals (Sweden)

    Koblbauer Ian FH

    2011-10-01

    Full Text Available Abstract Background Patients undergoing total knee arthroplasty (TKA often experience strength deficits both pre- and post-operatively. As these deficits may have a direct impact on functional recovery, strength assessment should be performed in this patient population. For these assessments, reliable measurements should be used. This study aimed to determine the inter- and intrarater reliability of hand-held dynamometry (HHD in measuring isometric knee strength in patients awaiting TKA. Methods To determine interrater reliability, 32 patients (81.3% female were assessed by two examiners. Patients were assessed consecutively by both examiners on the same individual test dates. To determine intrarater reliability, a subgroup (n = 13 was again assessed by the examiners within four weeks of the initial testing procedure. Maximal isometric knee flexor and extensor strength were tested using a modified Citec hand-held dynamometer. Both the affected and unaffected knee were tested. Reliability was assessed using the Intraclass Correlation Coefficient (ICC. In addition, the Standard Error of Measurement (SEM and the Smallest Detectable Difference (SDD were used to determine reliability. Results In both the affected and unaffected knee, the inter- and intrarater reliability were good for knee flexors (ICC range 0.76-0.94 and excellent for knee extensors (ICC range 0.92-0.97. However, measurement error was high, displaying SDD ranges between 21.7% and 36.2% for interrater reliability and between 19.0% and 57.5% for intrarater reliability. Overall, measurement error was higher for the knee flexors than for the knee extensors. Conclusions Modified HHD appears to be a reliable strength measure, producing good to excellent ICC values for both inter- and intrarater reliability in a group of TKA patients. High SEM and SDD values, however, indicate high measurement error for individual measures. This study demonstrates that a modified HHD is appropriate to

  19. Interrater and Test-Retest Reliability and Minimal Detectable Change of the Balance Evaluation Systems Test (BESTest) and Subsystems With Community-Dwelling Older Adults.

    Science.gov (United States)

    Wang-Hsu, Elizabeth; Smith, Susan S

    2017-01-10

    Falls are a common cause of injuries and hospital admissions in older adults. Balance limitation is a potentially modifiable factor contributing to falls. The Balance Evaluation Systems Test (BESTest), a clinical balance measure, categorizes balance into 6 underlying subsystems. Each of the subsystems is scored individually and summed to obtain a total score. The reliability of the BESTest and its individual subsystems has been reported in patients with various neurological disorders and cancer survivors. However, the reliability and minimal detectable change (MDC) of the BESTest with community-dwelling older adults have not been reported. The purposes of our study were to (1) determine the interrater and test-retest reliability of the BESTest total and subsystem scores; and (2) estimate the MDC of the BESTest and its individual subsystem scores with community-dwelling older adults. We used a prospective cohort methodological design. Community-dwelling older adults (N = 70; aged 70-94 years; mean = 85.0 [5.5] years) were recruited from a senior independent living community. Trained testers (N = 3) administered the BESTest. All participants were tested with the BESTest by the same tester initially and then retested 7 to 14 days later. With 32 of the participants, a second tester concurrently scored the retest for interrater reliability. Testers were blinded to each other's scores. Intraclass correlation coefficients [ICC(2,1)] were used to determine the interrater and test-retest reliability. Test-retest reliability was also analyzed using method error and the associated coefficients of variation (CVME). MDC was calculated using standard error of measurement. Interrater reliability (N = 32) of the BESTest total score was ICC(2, 1) = 0.97 (95% confidence interval [CI], 0.94-0.99). The ICCs for the individual subsystem scores ranged from 0.85 to 0.94. Test-retest reliability (N = 70) of the BESTest total score was ICC(2,1) = 0.93 (95% CI, 0.89-0.96). ICCs for the

  20. Predicting hydrological response to forest changes by simple statistical models: the selection of the best indicator of forest changes with a hydrological perspective

    Science.gov (United States)

    Ning, D.; Zhang, M.; Ren, S.; Hou, Y.; Yu, L.; Meng, Z.

    2017-01-01

    Forest plays an important role in hydrological cycle, and forest changes will inevitably affect runoff across multiple spatial scales. The selection of a suitable indicator for forest changes is essential for predicting forest-related hydrological response. This study used the Meijiang River, one of the headwaters of the Poyang Lake as an example to identify the best indicator of forest changes for predicting forest change-induced hydrological responses. Correlation analysis was conducted first to detect the relationships between monthly runoff and its predictive variables including antecedent monthly precipitation and indicators for forest changes (forest coverage, vegetation indices including EVI, NDVI, and NDWI), and by use of the identified predictive variables that were most correlated with monthly runoff, multiple linear regression models were then developed. The model with best performance identified in this study included two independent variables -antecedent monthly precipitation and NDWI. It indicates that NDWI is the best indicator of forest change in hydrological prediction while forest coverage, the most commonly used indicator of forest change is insignificantly related to monthly runoff. This highlights the use of vegetation index such as NDWI to indicate forest changes in hydrological studies. This study will provide us with an efficient way to quantify the hydrological impact of large-scale forest changes in the Meijiang River watershed, which is crucial for downstream water resource management and ecological protection in the Poyang Lake basin.

  1. Reliability Standards of Complex Engineering Systems

    Science.gov (United States)

    Galperin, E. M.; Zayko, V. A.; Gorshkalev, P. A.

    2017-11-01

    Production and manufacture play an important role in today’s modern society. Industrial production is nowadays characterized by increased and complex communications between its parts. The problem of preventing accidents in a large industrial enterprise becomes especially relevant. In these circumstances, the reliability of enterprise functioning is of particular importance. Potential damage caused by an accident at such enterprise may lead to substantial material losses and, in some cases, can even cause a loss of human lives. That is why industrial enterprise functioning reliability is immensely important. In terms of their reliability, industrial facilities (objects) are divided into simple and complex. Simple objects are characterized by only two conditions: operable and non-operable. A complex object exists in more than two conditions. The main characteristic here is the stability of its operation. This paper develops the reliability indicator combining the set theory methodology and a state space method. Both are widely used to analyze dynamically developing probability processes. The research also introduces a set of reliability indicators for complex technical systems.

  2. The reliability of the Associate Platinum digital foot scanner in measuring previously developed footprint characteristics: a technical note.

    Science.gov (United States)

    Papuga, M Owen; Burke, Jeanmarie R

    2011-02-01

    An ink pad and paper, pressure-sensitive platforms, and photography have previously been used to collect footprint data used in clinical assessment. Digital scanners have been widely used more recently to collect such data. The purpose of this study was to evaluate the intra- and interrater reliability of a flatbed digital image scanning technology to capture footprint data. This study used a repeated-measures design on 32 (16 male 16 female) healthy subjects. The following measured indices of footprint were recorded from 2-dimensional images of the plantar surface of the foot recorded with an Associate Platinum (Foot Levelers Inc, Roanoke, VA) digital foot scanner: Staheli index, Chippaux-Smirak index, arch angle, and arch index. Intraclass correlation coefficient (ICC) values were calculated to evaluate intrarater, interday, and interclinician reliability. The ICC values for intrarater reliability were greater than or equal to .817, indicating an excellent level of reproducibility in assessing the collected images. Analyses of variance revealed that there were no significant differences between raters for each index (P > .05). The ICC values also indicated excellent reliability (.881-.971) between days and clinicians in all but one of the indices of footprint, arch angle (.689), with good reliability between clinicians. The full-factorial analysis of variance model did not reveal any interaction effects (P > .05), which indicated that indices of footprint were not changing across days and clinicians. Scanning technology used in this study demonstrated good intra- and interrater reliability measurements of footprint indices, as demonstrated by high ICC values. Copyright © 2011 National University of Health Sciences. Published by Mosby, Inc. All rights reserved.

  3. Aerospace reliability applied to biomedicine.

    Science.gov (United States)

    Lalli, V. R.; Vargo, D. J.

    1972-01-01

    An analysis is presented that indicates that the reliability and quality assurance methodology selected by NASA to minimize failures in aerospace equipment can be applied directly to biomedical devices to improve hospital equipment reliability. The Space Electric Rocket Test project is used as an example of NASA application of reliability and quality assurance (R&QA) methods. By analogy a comparison is made to show how these same methods can be used in the development of transducers, instrumentation, and complex systems for use in medicine.

  4. Linear trend and abrupt changes of climate indices in the arid region of northwestern China

    Science.gov (United States)

    Wang, Huaijun; Pan, Yingping; Chen, Yaning; Ye, Zhengwei

    2017-11-01

    In recent years, climate extreme events have caused increasing direct economic and social losses in the arid region of northwestern China. Based on daily temperature and precipitation data from 1960 to 2010, this paper discussed the linear trend and abrupt changes of climate indices. The general evolution was obtained by the empirical orthogonal function (EOF), the Mann-Kendall test, and the distribution-free cumulative sum chart (CUSUM) test. The results are as follows: (1) climate showed a warming trend at annual and seasonal scale, with all temperature indices exhibiting statistically significant changes. The warm indices have increased, with 1.37%days/decade of warm days (TX90p), 0.17 °C/decade of warmest days (TXx) and 1.97 days/decade of warm spell duration indicator (WSDI), respectively. The cold indices have decreased, with - 1.89%days/decade, 0.65 °C/decade and - 0.66 days/decade for cold nights (TN10p), coldest nights (TNn) and cold spell duration indicator (CSDI), respectively. The precipitation indices have also increased significantly, coupled with the changes of magnitude (max 1-day precipitation amount (RX1day)), frequency (rain day (R0.1)), and duration (consecutive dry days (CDD)). (2) Abrupt changes of the annual regional precipitation indices and the minimum temperature indices were observed around 1986, and that of the maximum temperature indices were observed in 1996. (3) The EOF1 indicated the overall coherent distribution for the whole study area, and its principal component (PC1) was also observed, showing a significant linear trend with an abrupt change, which were in accordance with the regional observation results. EOF2 and EOF3 show contrasts between the southern and northern study areas, and between the eastern and western study areas, respectively, whereas no significant tendency was observed for their PCs. Hence, the climate indices have changed significantly, with linear trends and abrupt changes noted for all climate indices

  5. Problem of nuclear power plant reliability

    International Nuclear Information System (INIS)

    Popyrin, L.S.; Nefedov, Yu.V.

    1989-01-01

    The problem of substantiation of rational and methods of ensurance of NPP reliability at the stage of its designing has been studied. It is shown that the optimal level of NPP reliability is determined by coordinating solution of the proiblems for optimization of reliability of power industry, heat and power supply and nuclear power generation systems comprising NPP, and problems of reliability optimization of NPP proper, as a complex engineering system. The conclusion is made that the greatest attention should be paid to the development of mathematical models of reliability, taking into account different methods of equipment redundancy, as well as dependence of failures on barious factors, improvement of NPP reliability indices, development of data base, working out of the complec of consistent standards of reliability. 230 refs.; 2 figs.; 1 tab

  6. Practice effects and test-re-test reliability of the Five Digit Test in patients with stroke over four serial assessments.

    Science.gov (United States)

    Chiu, En-Chi; Koh, Chia-Lin; Tsai, Chia-Yin; Lu, Wen-Shian; Sheu, Ching-Fan; Hsueh, I-Ping; Hsieh, Ching-Lin

    2014-01-01

    To investigate practice effect and test-re-test reliability of the Five Digit Test (FDT) over four serial assessments in patients with stroke. Single-group repeated measures design. Twenty-five patients with stroke were administered the FDT in four consecutive assessments every 2 weeks. The FDT contains four parts with five indices: 'basic measures of attention and processing speed', 'selective attention', 'alternating attention', 'ability of inhibition' and 'ability of switching'. The five indices of the FDT showed trivial-to-small practice effects (Cohen's d = 0.03-0.47) and moderate-to-excellent test-re-test reliability (intra-class correlation coefficient = 0.59-0.97). Practice effects of the five indices all appeared cumulative, but one index, 'basic measures of attention and processing speed', reached a plateau after the second assessment. The minimum and maximum values of the 90% confidence interval (CI) of reliable change index modified for practice (RCIp) for this index were [-17.6, 11.2]. One of five indices of the FDT reached a plateau, whose minimum and maximum values of the 90% CI RCIp are useful to determine whether the change in an individual's score is real. However, clinicians and researchers should be cautious when interpreting the test results of these four indices over repeated assessments.

  7. Risk-based plant performance indicators

    International Nuclear Information System (INIS)

    Boccio, J.L.; Azarm, M.A.; Hall, R.E.

    1991-01-01

    Tasked by the 1979 President's Commission on the Accident at Three Mile Island, the U.S. nuclear power industry has put into place a performance indicator program as one means for showing a demonstrable record of achievement. Largely through the efforts of the Institute of Nuclear Power Operations (INPO), plant performance data has, since 1983, been collected and analyzed to aid utility management in measuring their plants' performance progress. The U.S. Nuclear Regulatory Commission (NRC) has also developed a set of performance indicators. This program, conducted by NRC's Office for the Analysis and Evaluation of Operational Data (AEOD), is structured to present information on plant operational performance in a manner that could enhance the staff's ability to recognize changes in the safety performance. Both organizations recognized that performance indicators have limitations and could be subject to misinterpretation and misuse with the potential for an adverse impact on safety. This paper reports on performance indicators presently in use, e.g., unplanned automatic scrams, unplanned safety system actuation, safety system failures, etc., which are logically related to safety. But, a reliability/risk-based method for evaluating either individual indicators or an aggregated set of indicators is not yet available

  8. Field reliability of electronic systems

    International Nuclear Information System (INIS)

    Elm, T.

    1984-02-01

    This report investigates, through several examples from the field, the reliability of electronic units in a broader sense. That is, it treats not just random parts failure, but also inadequate reliability design and (externally and internally) induced failures. The report is not meant to be merely an indication of the state of the art for the reliability prediction methods we know, but also as a contribution to the investigation of man-machine interplay in the operation and repair of electronic equipment. The report firmly links electronics reliability to safety and risk analyses approaches with a broader, system oriented view of reliability prediction and with postfailure stress analysis. It is intended to reveal, in a qualitative manner, the existence of symptom and cause patterns. It provides a background for further investigations to identify the detailed mechanisms of the faults and the remedical actions and precautions for achieving cost effective reliability. (author)

  9. Comparison of clay mineral stratigraphy to other proxy palaeoclimate indicators in the Mesozoic of NW Europe.

    Science.gov (United States)

    Ruffell, Alastair; McKinley, Jennifer M; Worden, Richard H

    2002-04-15

    This paper reviews the opportunities and pitfalls associated with using clay mineralogical analysis in palaeoclimatic reconstructions. Following this, conjunctive methods of improving the reliability of clay mineralogical analysis are reviewed. The Mesozoic succession of NW Europe is employed as a case study. This demonstrates the relationship between clay mineralogy and palaeoclimate. Proxy analyses may be integrated with clay mineralogical analysis to provide an assessment of aridity-humidity contrasts in the hinterland climate. As an example, the abundance of kaolinite through the Mesozoic shows that, while interpretations may be difficult, the Mesozoic climate of NW Europe was subject to great changes in rates of continental precipitation. We may compare sedimentological (facies, mineralogy, geochemistry) indicators of palaeoprecipitation with palaeotemperature estimates. The integration of clay mineralogical analyses with other sedimentological proxy indicators of palaeoclimate allows differentiation of palaeoclimatic effects from those of sea-level and tectonic change. We may also observe how widespread palaeoclimate changes were; whether they were diachronous or synchronous; how climate, sea level and tectonics interact to control sedimentary facies and what palaeoclimate indicators are reliable.

  10. Is air-displacement plethysmography a reliable method of detecting ongoing changes in percent body fat within obese children involved in a weight management program?

    DEFF Research Database (Denmark)

    Ewane, Cecile; McConkey, Stacy A; Kreiter, Clarence D

    2010-01-01

    (percent body fat) over time. The gold standard method, hydrodensitometry, has severe limitations for the pediatric population. OBJECTIVE: This study examines the reliability of air-displacement plethysmography (ADP) in detecting percent body fat changes within obese children over time. METHODS: Percent...... body fat by ADP, weight, and body mass index (BMI) were measured for eight obese children aged 5-12 years enrolled in a weight management program over a 12-month period. These measurements were taken at initial evaluation, 1.5 months, 3 months, 6 months, and 12 months to monitor the progress...... of the subjects and detect any changes in these measures over time. Statistical analysis was used to determine the reliability of the data collected. RESULTS: The reliability estimate for percent body fat by ADP was 0.78. This was much lower than the reliability of BMI, 0.98, and weight measurements, 0...

  11. Reliability of a patient survey assessing cost-related changes in health care use among high deductible health plan enrollees

    Directory of Open Access Journals (Sweden)

    Galbraith Alison A

    2011-05-01

    Full Text Available Abstract Background Recent increases in patient cost-sharing for health care have lent increasing importance to monitoring cost-related changes in health care use. Despite the widespread use of survey questions to measure changes in health care use and related behaviors, scant data exists on the reliability of such questions. Methods We administered a cross-sectional survey to a stratified random sample of families in a New England health plan's high deductible health plan (HDHP with ≥ $500 in annualized out-of-pocket expenditures. Enrollees were asked about their knowledge of their plan, information seeking, behavior change associated with having a deductible, experience of delay in care due in part to cost, and hypothetical delay in care due in part to cost. Initial respondents were mailed a follow-up survey within two weeks of each family returning the original survey. We computed several agreement statistics to measure the test-retest reliability for select questions. We also conducted continuity adjusted chi-square, and McNemar tests in both the original and follow-up samples to measure the degree to which our results could be reproduced. Analyses were stratified by self-reported income. Results The test-retest reliability was moderate for the majority of questions (0.41 - 0.60 and the level of test-retest reliability did not differ substantially across each of the broader domains of questions. The observed proportions of respondents with delayed or foregone pediatric, adult, or any family care were similar when comparing the original and follow-up surveys. In the original survey, respondents in the lower-income group were more likely to delay or forego pediatric care, adult care, or any family care. All of the tests comparing income groups in the follow-up survey produced the same result as in the original survey. Conclusions In this population of HDHP beneficiaries, we found that survey questions concerning plan knowledge, information

  12. Reliability of ultrasound thickness measurement of the abdominal muscles during clinical isometric endurance tests.

    Science.gov (United States)

    ShahAli, Shabnam; Arab, Amir Massoud; Talebian, Saeed; Ebrahimi, Esmaeil; Bahmani, Andia; Karimi, Noureddin; Nabavi, Hoda

    2015-07-01

    The study was designed to evaluate the intra-examiner reliability of ultrasound (US) thickness measurement of abdominal muscles activity when supine lying and during two isometric endurance tests in subjects with and without Low back pain (LBP). A total of 19 women (9 with LBP, 10 without LBP) participated in the study. Within-day reliability of the US thickness measurements at supine lying and the two isometric endurance tests were assessed in all subjects. The intra-class correlation coefficient (ICC) was used to assess the relative reliability of thickness measurement. The standard error of measurement (SEM), minimal detectable change (MDC) and the coefficient of variation (CV) were used to evaluate the absolute reliability. Results indicated high ICC scores (0.73-0.99) and also small SEM and MDC scores for within-day reliability assessment. The Bland-Altman plots of agreement in US measurement of the abdominal muscles during the two isometric endurance tests demonstrated that 95% of the observations fall between the limits of agreement for test and retest measurements. Together the results indicate high intra-tester reliability for the US measurement of the thickness of abdominal muscles in all the positions tested. According to the study's findings, US imaging can be used as a reliable method for assessment of abdominal muscles activity in supine lying and the two isometric endurance tests employed, in participants with and without LBP. Copyright © 2014 Elsevier Ltd. All rights reserved.

  13. Tracking and unpacking rapid Arctic change: Indicators of community health and sustainability in northern Alaska and links to cryospheric change

    Science.gov (United States)

    Eicken, H.; Sam, J. M.; Mueller-stoffels, M.; Lovecraft, A. L.; Fresco, N. L.

    2017-12-01

    Tracking and responding to rapid Arctic change benefits from time series of indicator variables that describe the state of the system and can inform anticipatory action. A key challenge is to identify and monitor sets of indicators that capture relevant variability, trends, and transitions in social-environmental systems. We present findings from participatory scenarios focused on community health and sustainability in northern Alaska. In a series of workshops in 2015 and 2016 (Kotzebue workshop photo shown below), over 50 experts, mostly local, identified determinants of community health and sustainability by 2040 in the Northwest Arctic and North Slope Boroughs, Alaska. Drawing on further research, an initial set of factors and uncertainties was refined and prioritized into a total of 20 key drivers, ranging from governance issues to socio-economic and environmental factors. The research team then developed sets of future projections that describe plausible outcomes by mid-century for each of these drivers. A plausibility and consistency analysis of all pairwise combinations of these projections (following Mueller-Stoffels and Eicken, In: North by 2020 - Perspectives on Alaska's Changing Social-Ecological Systems, University of Alaska Press, 2011) resulted in the identification of robust scenarios. The latter were further reviewed by workshop participants, and a set of indicator variables, including indicators of relevant cryospheric change, was identified to help track trajectories towards plausible future states. Publically accessible recorded data only exist for a subset of the more than 70 indicators, reaching back a few years to several decades. For several indicators, the sampling rate or time series length are insufficient for tracking of and response to change. A core set of variables has been identified that meets indicator requirements and can serve as a tool for Alaska Arctic communities in adapting to or mitigating rapid change affecting community

  14. Reliability analysis of the epidural spinal cord compression scale.

    Science.gov (United States)

    Bilsky, Mark H; Laufer, Ilya; Fourney, Daryl R; Groff, Michael; Schmidt, Meic H; Varga, Peter Paul; Vrionis, Frank D; Yamada, Yoshiya; Gerszten, Peter C; Kuklo, Timothy R

    2010-09-01

    The evolution of imaging techniques, along with highly effective radiation options has changed the way metastatic epidural tumors are treated. While high-grade epidural spinal cord compression (ESCC) frequently serves as an indication for surgical decompression, no consensus exists in the literature about the precise definition of this term. The advancement of the treatment paradigms in patients with metastatic tumors for the spine requires a clear grading scheme of ESCC. The degree of ESCC often serves as a major determinant in the decision to operate or irradiate. The purpose of this study was to determine the reliability and validity of a 6-point, MR imaging-based grading system for ESCC. To determine the reliability of the grading scale, a survey was distributed to 7 spine surgeons who participate in the Spine Oncology Study Group. The MR images of 25 cervical or thoracic spinal tumors were distributed consisting of 1 sagittal image and 3 axial images at the identical level including T1-weighted, T2-weighted, and Gd-enhanced T1-weighted images. The survey was administered 3 times at 2-week intervals. The inter- and intrarater reliability was assessed. The inter- and intrarater reliability ranged from good to excellent when surgeons were asked to rate the degree of spinal cord compression using T2-weighted axial images. The T2-weighted images were superior indicators of ESCC compared with T1-weighted images with and without Gd. The ESCC scale provides a valid and reliable instrument that may be used to describe the degree of ESCC based on T2-weighted MR images. This scale accounts for recent advances in the treatment of spinal metastases and may be used to provide an ESCC classification scheme for multicenter clinical trial and outcome studies.

  15. Reliability of measuring abductor hallucis muscle parameters using two different diagnostic ultrasound machines

    Directory of Open Access Journals (Sweden)

    Cameron Alyse FM

    2009-11-01

    Full Text Available Abstract Background Diagnostic ultrasound provides a method of analysing soft tissue structures of the musculoskeletal system effectively and reliably. The aim of this study was to evaluate within and between session reliability of measuring muscle dorso-plantar thickness, medio-lateral length and cross-sectional area, of the abductor hallucis muscle using two different ultrasound machines, a higher end Philips HD11 Ultrasound machine and clinically orientated Chison 8300 Deluxe Digital Portable Ultrasound System. Methods The abductor hallucis muscle of both the left and right feet of thirty asymptomatic participants was imaged and then measured using both ultrasound machines. Interclass correlation coefficients (ICC with 95% confidence intervals (CI were used to calculate both within and between session intra-tester reliability. Standard error of the measurement (SEM calculations were undertaken to assess difference between the actual measured score across trials and the smallest real difference (SRD was calculated from the SEM to indicate the degree of change that would exceed the expected trial to trial variability. Results The ICCs, SEM and SRD for dorso-plantar thickness and medial-lateral length were shown to have excellent to high within and between-session reliability for both ultrasound machines. The between-session reliability indices for cross-sectional area were acceptable for both ultrasound machines. Conclusion The results of the current study suggest that regardless of the type ultrasound machine, intra-tester reliability for the measurement the abductor hallucis muscle parameters is very high.

  16. Reliability tasks from prediction to field use

    International Nuclear Information System (INIS)

    Guyot, Christian.

    1975-01-01

    This tutorial paper is part of a series intended to sensitive on reliability prolems. Reliability probabilistic concept, is an important parameter of availability. Reliability prediction is an estimation process for evaluating design progress. It is only by the application of a reliability program that reliability objectives can be attained through the different stages of work: conception, fabrication, field use. The user is mainly interested in operational reliability. Indication are given on the support and the treatment of data in the case of electronic equipment at C.E.A. Reliability engineering requires a special state of mind which must be formed and developed in a company in the same way as it may be done for example for safety [fr

  17. Reliability and sensitivity to change of the OMERACT rheumatoid arthritis magnetic resonance imaging score in a multireader, longitudinal setting

    DEFF Research Database (Denmark)

    Haavardsholm, ea; Østergaard, Mikkel; Kvan, NP

    2005-01-01

    OBJECTIVE: To assess the intra- and interreader reliability and the sensitivity to change of the Outcome Measures in Rheumatology Clinical Trials (OMERACT) Rheumatoid Arthritis Magnetic Resonance Imaging Score (RAMRIS) system on digital images of the wrist joints of patients with early or establi...

  18. Some remarks on software reliability

    International Nuclear Information System (INIS)

    Gonzalez Hernando, J.; Sanchez Izquierdo, J.

    1978-01-01

    Trend in modern NPPCI is toward a broad use of programmable elements. Some aspects concerning present status of programmable digital systems reliability are reported. Basic differences between software and hardware concept require a specific approach in all the reliability topics concerning software systems. The software reliability theory was initialy developed upon hardware models analogies. At present this approach is changing and specific models are being developed. The growing use of programmable systems necessitates emphasizing the importance of more adequate regulatory requirements to include this technology in NPPCI. (author)

  19. Variable reliability of surrogate measures of insulin sensitivity after Roux-en-Y gastric bypass

    DEFF Research Database (Denmark)

    Bojsen-Møller, Kirstine N; Dirksen, Carsten; Svane, Maria Saur

    2017-01-01

    ) are frequently used, but have not been validated after RYGB. Our aim was to evaluate whether surrogate indices reliably estimate changes in insulin sensitivity after RYGB. Four fasting (inverse-HOMA-IR, HOMA2-%S, QUICKI, revised-QUICKI) and three OGTT-derived surrogates (Matsuda, Gutt, OGIS) were compared...... postoperatively. Post-RYGB changes in inverse-HOMA-IR and HOMA2-%S did not correlate with changes in Rd at any visit, but were comparable to changes in HISI at 1 week. Changes in QUICKI and revised-QUICKI correlated with Rd/I after surgery. Changes in Matsuda and Gutt did not correlate with changes in Rd/I and Rd...

  20. Reliability of change in lumbar MRI findings over time in patients with and without disc prosthesis - comparing two different image evaluation methods

    International Nuclear Information System (INIS)

    Berg, Linda; Espeland, Ansgar; Gjertsen, Oeivind; Hellum, Christian; Neckelmann, Gesche; Johnsen, Lars G.; Eide, Geir E.

    2012-01-01

    To assess the reliability of change in lumbar magnetic resonance imaging (MRI) findings evaluated retrospectively by direct comparison of images and by non-comparison. Pre-treatment and 2-year follow-up MRI was performed in 126 patients randomized to disc prosthesis surgery or non-surgical treatment. Two experienced radiologists independently evaluated progress and regress for Modic changes, disc findings, and facet arthropathy (FA) at L3/L4, L4/L5, and L5/S1, both by non-comparison and by comparison of initial and follow-up images. FA was evaluated at all levels, and other findings at non-operated levels. We calculated prevalence- and bias-adjusted kappa (PABAK) values for interobserver agreement. The impact of an adjacent prosthesis (which causes artefacts) and image evaluation method on PABAK was assessed using generalized estimating equations. Image comparison indicated good interobserver agreement on progress and regress (PABAK 0.63-1.00) for Modic changes, posterior high-intensity zone, disc height, and disc contour at L3-S1 and for nucleus pulposus signal and FA at L3/L4; and moderate interobserver agreement (PABAK 0.46-0.59) on decreasing nucleus signal and increasing FA at L4-S1. Image comparison indicated lower (but fair) interobserver agreement (PABAK 0.29) only for increasing FA at L5/S1 in patients with prosthesis in L4/L5 and/or L5/S1. An adjacent prosthesis had no overall impact on PABAK values (p ≥ 0.22). Comparison yielded higher PABAK values than non-comparison (p < 0.001). Regarding changes in lumbar MRI findings over time, comparison of images can provide moderate or good interobserver agreement, and better agreement than non-comparison. An adjacent prosthesis may not reduce agreement on change for most findings. (orig.)

  1. Comparison of reliability and responsiveness of patient-reported clinical outcome measures in knee osteoarthritis rehabilitation.

    Science.gov (United States)

    Williams, Valerie J; Piva, Sara R; Irrgang, James J; Crossley, Chad; Fitzgerald, G Kelley

    2012-08-01

    Secondary analysis, pretreatment-posttreatment observational study. To compare the reliability and responsiveness of the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), the Knee Outcome Survey activities of daily living subscale (KOS-ADL), and the Lower Extremity Functional Scale (LEFS) in individuals with knee osteoarthritis (OA). The WOMAC is the current standard in patient-reported measures of function in patients with knee OA. The KOS-ADL and LEFS were designed for potential use in patients with knee OA. If the KOS-ADL and LEFS are to be considered viable alternatives to the WOMAC for measuring patient-reported function in individuals with knee OA, they should have measurement properties comparable to the WOMAC. It would also be important to determine whether either of these instruments may be superior to the WOMAC in terms of reliability or responsiveness in this population. Data from 168 subjects with knee OA, who participated in a rehabilitation program, were used in the analyses. Reliability and responsiveness of each outcome measure were estimated at follow-ups of 2, 6, and 12 months. Reliability was estimated by calculating the intraclass correlation coefficient (ICC2,1) for subjects who were unchanged in status from baseline at each follow-up time, based on a global rating of change score. To examine responsiveness, the standard error of the measurement, minimal detectable change, minimal clinically important difference, and the Guyatt responsiveness index were calculated for each outcome measure at each follow-up time. All 3 outcome measures demonstrated reasonable reliability and responsiveness to change. Reliability and responsiveness tended to decrease somewhat with increasing follow-up time. There were no substantial differences between outcome measures for reliability or any of the 3 measures of responsiveness at any follow-up time. The results do not indicate that one outcome measure is more reliable or responsive than

  2. The use of specialisation indices to predict vulnerability of coral-feeding butterflyfishes to environmental change

    KAUST Repository

    Lawton, Rebecca J.

    2011-07-14

    In the absence of detailed assessments of extinction risk, ecological specialisation is often used as a proxy of vulnerability to environmental disturbances and extinction risk. Numerous indices can be used to estimate specialisation; however, the utility of these different indices to predict vulnerability to future environmental change is unknown. Here we compare the performance of specialisation indices using coral-feeding butterflyfishes as a model group. Our aims were to 1) quantify the dietary preferences of three butterflyfish species across habitats with differing levels of resource availability; 2) investigate how estimates of dietary specialisation vary with the use of different specialisation indices; 3) determine which specialisation indices best inform predictions of vulnerability to environmental change; and 4) assess the utility of resource selection functions to inform predictions of vulnerability to environmental change. The relative level of dietary specialisation estimated for all three species varied when different specialisation indices were used, indicating that the choice of index can have a considerable impact upon estimates of specialisation. Specialisation indices that do not consider resource abundance may fail to distinguish species that primarily use common resources from species that actively target resources disproportionately more than they are available. Resource selection functions provided the greatest insights into the potential response of species to changes in resource availability. Examination of resource selection functions, in addition to specialisation indices, indicated that Chaetodon trifascialis was the most specialised feeder, with highly conserved dietary preferences across all sites, suggesting that this species is highly vulnerable to the impacts of climate-induced coral loss on reefs. Our results indicate that vulnerability assessments based on some specialisation indices may be misleading and the best estimates of

  3. Reliability of electronic systems

    International Nuclear Information System (INIS)

    Roca, Jose L.

    2001-01-01

    Reliability techniques have been developed subsequently as a need of the diverse engineering disciplines, nevertheless they are not few those that think they have been work a lot on reliability before the same word was used in the current context. Military, space and nuclear industries were the first ones that have been involved in this topic, however not only in these environments it is that it has been carried out this small great revolution in benefit of the increase of the reliability figures of the products of those industries, but rather it has extended to the whole industry. The fact of the massive production, characteristic of the current industries, drove four decades ago, to the fall of the reliability of its products, on one hand, because the massively itself and, for other, to the recently discovered and even not stabilized industrial techniques. Industry should be changed according to those two new requirements, creating products of medium complexity and assuring an enough reliability appropriated to production costs and controls. Reliability began to be integral part of the manufactured product. Facing this philosophy, the book describes reliability techniques applied to electronics systems and provides a coherent and rigorous framework for these diverse activities providing a unifying scientific basis for the entire subject. It consists of eight chapters plus a lot of statistical tables and an extensive annotated bibliography. Chapters embrace the following topics: 1- Introduction to Reliability; 2- Basic Mathematical Concepts; 3- Catastrophic Failure Models; 4-Parametric Failure Models; 5- Systems Reliability; 6- Reliability in Design and Project; 7- Reliability Tests; 8- Software Reliability. This book is in Spanish language and has a potentially diverse audience as a text book from academic to industrial courses. (author)

  4. Test-retest and between-site reliability in a multicenter fMRI study.

    Science.gov (United States)

    Friedman, Lee; Stern, Hal; Brown, Gregory G; Mathalon, Daniel H; Turner, Jessica; Glover, Gary H; Gollub, Randy L; Lauriello, John; Lim, Kelvin O; Cannon, Tyrone; Greve, Douglas N; Bockholt, Henry Jeremy; Belger, Aysenil; Mueller, Bryon; Doty, Michael J; He, Jianchun; Wells, William; Smyth, Padhraic; Pieper, Steve; Kim, Seyoung; Kubicki, Marek; Vangel, Mark; Potkin, Steven G

    2008-08-01

    In the present report, estimates of test-retest and between-site reliability of fMRI assessments were produced in the context of a multicenter fMRI reliability study (FBIRN Phase 1, www.nbirn.net). Five subjects were scanned on 10 MRI scanners on two occasions. The fMRI task was a simple block design sensorimotor task. The impulse response functions to the stimulation block were derived using an FIR-deconvolution analysis with FMRISTAT. Six functionally-derived ROIs covering the visual, auditory and motor cortices, created from a prior analysis, were used. Two dependent variables were compared: percent signal change and contrast-to-noise-ratio. Reliability was assessed with intraclass correlation coefficients derived from a variance components analysis. Test-retest reliability was high, but initially, between-site reliability was low, indicating a strong contribution from site and site-by-subject variance. However, a number of factors that can markedly improve between-site reliability were uncovered, including increasing the size of the ROIs, adjusting for smoothness differences, and inclusion of additional runs. By employing multiple steps, between-site reliability for 3T scanners was increased by 123%. Dropping one site at a time and assessing reliability can be a useful method of assessing the sensitivity of the results to particular sites. These findings should provide guidance toothers on the best practices for future multicenter studies.

  5. GPS IPW as a Meteorological Parameter and Climate Global Change Indicator

    Science.gov (United States)

    Kruczyk, M.; Liwosz, T.

    2011-12-01

    exaggerate). Especially intriguing are relatively unique shape of such series in different climates. Long lasting changes in weather conditions: 'dry' and 'wet' years are also visible. The longer and more uniform our series are the better chance to estimate the magnitude of climatological IWV changes. Homogenous ZTD solution during long period is great concern in this approach (problems with GPS strategy and reference system changes). In case of continental network (EUREF Permanent Network) reliable data we get only after reprocessing. Simple sinusoidal model has been adjusted to the IPW series (LS method) for selected stations (mainly Europe but also other continents - IGS stations), every year separately. Not only amplitudes but also phases of annual signal differ from year to year. Longer IPW series (up to 14 years) searched for some climatological signal sometimes reveal weak steady trend. Large number of GPS permanent stations, relative easiness of IPW derivation (only and surface meteo data needed apart from GPS solution) and water vapour significance in water cycle and global climate make this GPS IPW promising element of global environmental change monitoring.

  6. Evaluating Living Standard Indicators

    Directory of Open Access Journals (Sweden)

    Birčiaková Naďa

    2015-09-01

    Full Text Available This paper deals with the evaluation of selected available indicators of living standards, divided into three groups, namely economic, environmental, and social. We have selected six countries of the European Union for analysis: Bulgaria, the Czech Republic, Hungary, Luxembourg, France, and Great Britain. The aim of this paper is to evaluate indicators measuring living standards and suggest the most important factors which should be included in the final measurement. We have tried to determine what factors influence each indicator and what factors affect living standards. We have chosen regression analysis as our main method. From the study of factors, we can deduce their impact on living standards, and thus the value of indicators of living standards. Indicators with a high degree of reliability include the following factors: size and density of population, health care and spending on education. Emissions of carbon dioxide in the atmosphere also have a certain lower degree of reliability.

  7. Long-term reliability evaluation of nuclear containments with tendon force degradation

    International Nuclear Information System (INIS)

    Kim, Sang-Hyo; Choi, Moon-Seock; Joung, Jung-Yeun; Kim, Kun-Soo

    2013-01-01

    Highlights: • A probabilistic model on long-term degradation of tendon force is developed. • By using the model, we performed reliability evaluation of nuclear containment. • The analysis is also performed for the case with the strict maintenance programme. • We showed how to satisfy the target safety in the containments facing life extension. - Abstract: The long-term reliability of nuclear containment is important for operating nuclear power plants. In particular, long-term reliability should be clarified when the service life of nuclear containment is being extended. This study focuses not only on determining the reliability of nuclear containment but also presenting the reliability improvement by strengthening the containment itself or by running a strict maintenance programme. The degradation characteristics of tendon force are estimated from the data recorded during in-service inspection of containments. A reliability analysis is conducted for a limit state of through-wall cracking, which is conservative, but most crucial limit state. The results of this analysis indicate that reliability is the lowest at 3/4 height of the containment wall. Therefore, this location is the most vulnerable for the specific limit state considered in this analysis. Furthermore, changes in structural reliability owing to an increase in the number of inspecting tendons are analysed for verifying the effect of the maintenance program's intensity on expected containment reliability. In the last part of this study, an example of obtaining target reliability of nuclear containment by strengthening its structural resistance is presented. A case study is conducted for exemplifying the effect of strengthening work on containment reliability, especially during extended service life

  8. Operational safety performance indicator system - a management tool for the self assessment of safety and reliability of nuclear power plants

    International Nuclear Information System (INIS)

    Anil Kumar; Mandowara, S.L.; Mittal, S.

    2006-01-01

    Operational Safety Performance Indicator system is one of the self assessment tools for station management to monitor safety and reliability of nuclear power plants. It provides information to station management about the performance of various areas of the plants by means of different colours of relevant performance indicators. Such systems have been implemented at many nuclear power plants in the world and have been considered as strength during WANO Peer Review. IAEA had a Coordinated Research Programme (CRP) on this with several countries participating including India. In NPCIL this system has been implemented in KAPS about a year back and found very useful in identifying areas which needs to be given more attention. Based on the KAPS feedback Implementation of this system has been taken up in RAPS-3 and 4 and KGS-l and 2. (author)

  9. Dynamic k-out-of-n system reliability with component partnership

    International Nuclear Information System (INIS)

    Coit, David W.; Chatwattanasiri, Nida; Wattanapongsakorn, Naruemon; Konak, Abdullah

    2015-01-01

    This paper describes a new k-out-of-n system reliability model that is appropriate for certain design problems when the minimum number of required components, k, changes dynamically in response to failures to maximize the utility of the available collection of functioning components. This new model shares some distinct similarities with weighted k-out-of-n models and for some problems they produce the same result. However, there are subtle and distinct differences, and in practice, there are some complex applications have not been properly explained or modeled by traditional or extended k-out-of-n system models. For this application, components are arranged in a k-out-of-n configuration of heterogeneous components with different performance levels. Component performance is indicated by a component-specific component partnership level; the fewer partners required to operate successfully implies higher performance. The components can work collectively with partners at the same level to maintain system reliability, or they can create a partnership group with components at higher performance levels which serve as replacements to provide the necessary number of working components. When components fail, the dynamic k-out-of-n configuration maintains reliability of the system with changing k by having components create partnerships with other components at the same level or above. To demonstrate the model, a system replacement maintenance policy based on a replacement interval variable is applied to an example system to obtain the optimal replacement time. - Highlights: • A new k-out-of-n system reliability model is presented. • Components can form partnerships with other components. • The new k-out-of-n model is presented with a dynamic or changing k. • The new model is for systems with components that must work together in a group

  10. CSF lactate alone is not a reliable indicator of bacterial ventriculitis in patients with ventriculostomies.

    Science.gov (United States)

    Hill, Emily; Bleck, Thomas P; Singh, Kamaljit; Ouyang, Bichun; Busl, Katharina M

    2017-06-01

    In a febrile patient with a ventriculostomy, diagnosing or excluding bacterial or microbial ventriculitis is difficult, as conventional markers in analysis of cerebrospinal fluid (CSF) are not applicable due to presence of blood and inflammation. CSF lactate has been shown to be a useful indicator of bacterial meningitis in CSF obtained via lumbar puncture, but little and heterogenous data exist on patients with ventriculostomies. We reviewed all CSF analyses obtained via ventriculostomy in patients admitted to our tertiary medical center between 2008 and 2013, and constructed receiver operating characteristic (ROC) curves to evaluate the accuracy of CSF lactate concentration in discriminating a positive CSF culture from a negative one in setting of ventriculostomy and prophylactic antibiosis. Among 467 CSF lactate values, there were 22 corresponding CSF cultures with bacterial growth. Sensitivities and specificities for CSF lactate at threshold values 3, 4, 5 and 6mmol/L showed sensitivity and specificity greater than 70% for CSF lactate threshold 4mmol/L. The lowest threshold value of 3mmol/L resulted in higher sensitivity of 81.8%, and the highest chosen threshold value resulted in high specificity of 94.2%, but these values had poor corresponding specificity and sensitivity, respectively. The area under the curve was 0.82 (95% CI 0.72, 0.91). Our data from a large sample of CSF studies in patients with ventriculostomy indicate that no single value of CSF lactate provided both sensitivity and specificity high enough to be regarded as reliable test. Copyright © 2017 Elsevier B.V. All rights reserved.

  11. Accelerator Availability and Reliability Issues

    Energy Technology Data Exchange (ETDEWEB)

    Steve Suhring

    2003-05-01

    Maintaining reliable machine operations for existing machines as well as planning for future machines' operability present significant challenges to those responsible for system performance and improvement. Changes to machine requirements and beam specifications often reduce overall machine availability in an effort to meet user needs. Accelerator reliability issues from around the world will be presented, followed by a discussion of the major factors influencing machine availability.

  12. Technological advances and changing indications for lumbar puncture in neurological disorders.

    Science.gov (United States)

    Costerus, Joost M; Brouwer, Matthijs C; van de Beek, Diederik

    2018-03-01

    Technological advances have changed the indications for and the way in which lumbar puncture is done. Suspected CNS infection remains the most common indication for lumbar puncture, but new molecular techniques have broadened CSF analysis indications, such as the determination of neuronal autoantibodies in autoimmune encephalitis. New screening techniques have increased sensitvity for pathogen detection and can be used to identify pathogens that were previously unknown to cause CNS infections. Evidence suggests that potential treatments for neurodegenerative diseases, such as Alzheimer's disease, will rely on early detection of the disease with the use of CSF biomarkers. In addition to being used as a diagnostic tool, lumbar puncture can also be used to administer intrathecal treatments as shown by studies of antisense oligonucleotides in patients with spinal muscular atrophy. Lumbar puncture is generally a safe procedure but complications can occur, ranging from minor (eg, back pain) to potentially devastating (eg, cerebral herniation). Evidence that an atraumatic needle tip design reduces complications of lumbar puncture is compelling, and reinforces the need to change clinical practice. Copyright © 2018 Elsevier Ltd. All rights reserved.

  13. Reliability evaluation of power systems

    CERN Document Server

    Billinton, Roy

    1996-01-01

    The Second Edition of this well-received textbook presents over a decade of new research in power system reliability-while maintaining the general concept, structure, and style of the original volume. This edition features new chapters on the growing areas of Monte Carlo simulation and reliability economics. In addition, chapters cover the latest developments in techniques and their application to real problems. The text also explores the progress occurring in the structure, planning, and operation of real power systems due to changing ownership, regulation, and access. This work serves as a companion volume to Reliability Evaluation of Engineering Systems: Second Edition (1992).

  14. Neuronal Oscillations Indicate Sleep-dependent Changes in the Cortical Memory Trace.

    Science.gov (United States)

    Köster, Moritz; Finger, Holger; Kater, Maren-Jo; Schenk, Christoph; Gruber, Thomas

    2017-04-01

    Sleep promotes the consolidation of newly acquired associative memories. Here we used neuronal oscillations in the human EEG to investigate sleep-dependent changes in the cortical memory trace. The retrieval activity for object-color associations was assessed immediately after encoding and after 3 hr of sleep or wakefulness. Sleep had beneficial effects on memory performance and led to reduced event-related theta and gamma power during the retrieval of associative memories. Furthermore, event-related alpha suppression was attenuated in the wake group for memorized and novel stimuli. There were no sleep-dependent changes in retrieval activity for missed items or items retrieved without color. Thus, the sleep-dependent reduction in theta and gamma oscillations was specific for the retrieval of associative memories. In line with theoretical accounts on sleep-dependent memory consolidation, decreased theta may indicate reduced mediotemporal activity because of a transfer of information into neocortical networks during sleep, whereas reduced parietal gamma may reflect effects of synaptic downscaling. Changes in alpha suppression in the wake group possibly index reduced attentional resources that may also contribute to a lower memory performance in this group. These findings indicate that the consolidation of associative memories during sleep is associated with profound changes in the cortical memory trace and relies on multiple neuronal processes working in concert.

  15. Reliability of Power Units in Poland and the World

    Directory of Open Access Journals (Sweden)

    Józef Paska

    2015-09-01

    Full Text Available One of a power system’s subsystems is the generation subsystem consisting of power units, the reliability of which to a large extent determines the reliability of the power system and electricity supply to consumers. This paper presents definitions of the basic indices of power unit reliability used in Poland and in the world. They are compared and analysed on the basis of data published by the Energy Market Agency (Poland, NERC (North American Electric Reliability Corporation – USA, and WEC (World Energy Council. Deficiencies and the lack of a unified national system for collecting and processing electric power equipment unavailability data are also indicated.

  16. High intertester reliability of the cumulated ambulation score for the evaluation of basic mobility in patients with hip fracture

    DEFF Research Database (Denmark)

    Kristensen, Morten Tange; Andersen, Lene; Bech-Jensen, Rie

    2009-01-01

    OBJECTIVE: To examine the intertester reliability of the three activities of the Cumulated Ambulation Score (CAS) and the total CAS, and to define limits for the smallest change in basic mobility that indicates a real change in patients with hip fracture. DESIGN: An intertester reliability study....... SETTING: An acute 20-bed orthopaedic hip fracture unit. SUBJECTS: Fifty consecutive patients with a median age of 83 (25-75% quartile, 68-86) years. INTERVENTIONS: The CAS, which describes the patient's independency in three activities - (1) getting in and out of bed, (2) sit to stand from a chair, and (3...

  17. Test-Retest Reliability of Measurements of Hand-Grip Strength Obtained by Dynamometry from Older Adults: A Systematic Review of Research in the PubMed Database.

    Science.gov (United States)

    Bohannon, R W

    2017-01-01

    A systematic review was performed to summarize literature describing the test-retest reliability of grip strength measures obtained from older adults. Relevant literature was identified via a PubMed search. Seventeen articles were deemed appropriate based on inclusion and exclusion criteria. The relative test-retest reliability of grip strength measures obtained by dynamometry was good to excellent (intra-class correlation coefficients > 0.80) in all but 3 studies, which involved older adults with severe dementia. Absolute reliability, as indicated by summary statistics such as the minimum detectable change (95%), was more variable. As a percentage, that change ranged from 14.5% to 98.5%. Consequently, clinicians can be confident in the relative reliability of grip strength measures obtained from at risk older adults. However, relatively large percentage changes in grip strength may be necessary to conclude with confidence that a real change has occurred over time in some populations.

  18. Identifying marine pelagic ecosystem management objectives and indicators

    DEFF Research Database (Denmark)

    Trenkel, Verena M.; Hintzen, Niels T.; Farnsworth, Keith D.

    2015-01-01

    . Overall 26 objectives were proposed, with 58% agreement in proposed objectives between two workshops. Based on published evidence for pressure-state links, examples of operational objectives and suitable indicators for each of the 26 objectives were then selected. It is argued that given the strong......International policy frameworks such as the Common Fisheries Policy and the European Marine Strategy Framework Directive define high-level strategic goals for marine ecosystems. Strategic goals are addressed via general and operational management objectives. To add credibility and legitimacy...... scale in some cases. In the evidence-based approach used in this study, the selection of species or region specific operational objectives and indicators was based on demonstrated pressure-state links. Hence observed changes in indicators can reliably inform on appropriate management measures. (C) 2015...

  19. A reliability analysis of the revised competitiveness index.

    Science.gov (United States)

    Harris, Paul B; Houston, John M

    2010-06-01

    This study examined the reliability of the Revised Competitiveness Index by investigating the test-retest reliability, interitem reliability, and factor structure of the measure based on a sample of 280 undergraduates (200 women, 80 men) ranging in age from 18 to 28 years (M = 20.1, SD = 2.1). The findings indicate that the Revised Competitiveness Index has high test-retest reliability, high inter-item reliability, and a stable factor structure. The results support the assertion that the Revised Competitiveness Index assesses competitiveness as a stable trait rather than a dynamic state.

  20. Reliability worth assessment of radial systems with distributed generation

    OpenAIRE

    Bellart Llavall, Francesc Xavier

    2010-01-01

    With recent advances in technology, utilities generation (DG) on the distribution systems. Reliability worth is very important in power system planning and operation. Having a DG ensures reli increase the reliability worth. This research project presents the study of a radial distribution system and the impact of placing DG in order to increase the reliability worth. where a DG have to be placed. The reliability improvement is measured by different reliability indices tha...

  1. High-Reliability Health Care: Getting There from Here

    Science.gov (United States)

    Chassin, Mark R; Loeb, Jerod M

    2013-01-01

    Context Despite serious and widespread efforts to improve the quality of health care, many patients still suffer preventable harm every day. Hospitals find improvement difficult to sustain, and they suffer “project fatigue” because so many problems need attention. No hospitals or health systems have achieved consistent excellence throughout their institutions. High-reliability science is the study of organizations in industries like commercial aviation and nuclear power that operate under hazardous conditions while maintaining safety levels that are far better than those of health care. Adapting and applying the lessons of this science to health care offer the promise of enabling hospitals to reach levels of quality and safety that are comparable to those of the best high-reliability organizations. Methods We combined the Joint Commission's knowledge of health care organizations with knowledge from the published literature and from experts in high-reliability industries and leading safety scholars outside health care. We developed a conceptual and practical framework for assessing hospitals’ readiness for and progress toward high reliability. By iterative testing with hospital leaders, we refined the framework and, for each of its fourteen components, defined stages of maturity through which we believe hospitals must pass to reach high reliability. Findings We discovered that the ways that high-reliability organizations generate and maintain high levels of safety cannot be directly applied to today's hospitals. We defined a series of incremental changes that hospitals should undertake to progress toward high reliability. These changes involve the leadership's commitment to achieving zero patient harm, a fully functional culture of safety throughout the organization, and the widespread deployment of highly effective process improvement tools. Conclusions Hospitals can make substantial progress toward high reliability by undertaking several specific

  2. Developing a National Climate Indicators System to Track Climate Changes, Impacts, Vulnerabilities, and Preparedness

    Science.gov (United States)

    Kenney, M. A.; Janetos, A. C.; Arndt, D.; Chen, R. S.; Pouyat, R.; Anderson, S. M.

    2013-12-01

    The National Climate Assessment (NCA) is being conducted under the auspices of the U.S. Global Change Research Program (USGCRP), pursuant to the Global Change Research Act of 1990, Section 106, which requires a report to Congress every 4 years. Part of the vision, which is now under development, for the sustained National Climate Assessment (NCA) process is a system of physical, ecological, and societal indicators that communicate key aspects of the physical climate, climate impacts, vulnerabilities, and preparedness for the purpose of informing both decision makers and the public with scientifically valid information that is useful to inform decision-making processes such as the development and implementation of climate adaptation strategies in a particular sector or region. These indicators will be tracked as a part of ongoing assessment activities, with adjustments as necessary to adapt to changing conditions and understanding. The indicators will be reviewed and updated so that the system adapts to new information. The NCA indicator system is not intended to serve as a vehicle for documenting rigorous cause and effect relationships. It is reasonable, however, for it to serve as a guide to those factors that affect the evolution of variability and change in the climate system, the resources and sectors of concern that are affected by it, and how society chooses to respond. Different components of the end-to-end climate issue serve as categories within which to organize an end-to-end system of indicators: Greenhouse Gas Emissions and Sinks, Atmospheric Composition, Physical Climate Variability and Change, Sectors and Resources of Concern, and Adaptation and Mitigation Responses. This framing has several advantages. It can be used to identify the different components of the end-to-end climate issue that both decision-makers and researchers are interested in. It is independent of scale, and therefore allows the indicators themselves to be described at spatial

  3. Prediction of software operational reliability using testing environment factor

    International Nuclear Information System (INIS)

    Jung, Hoan Sung

    1995-02-01

    Software reliability is especially important to customers these days. The need to quantify software reliability of safety-critical systems has been received very special attention and the reliability is rated as one of software's most important attributes. Since the software is an intellectual product of human activity and since it is logically complex, the failures are inevitable. No standard models have been established to prove the correctness and to estimate the reliability of software systems by analysis and/or testing. For many years, many researches have focused on the quantification of software reliability and there are many models developed to quantify software reliability. Most software reliability models estimate the reliability with the failure data collected during the test assuming that the test environments well represent the operation profile. User's interest is on the operational reliability rather than on the test reliability, however. The experiences show that the operational reliability is higher than the test reliability. With the assumption that the difference in reliability results from the change of environment, testing environment factor comprising the aging factor and the coverage factor are defined in this work to predict the ultimate operational reliability with the failure data. It is by incorporating test environments applied beyond the operational profile into testing environment factor Test reliability can also be estimated with this approach without any model change. The application results are close to the actual data. The approach used in this thesis is expected to be applicable to ultra high reliable software systems that are used in nuclear power plants, airplanes, and other safety-critical applications

  4. Reliability analysis of shutdown system

    International Nuclear Information System (INIS)

    Kumar, C. Senthil; John Arul, A.; Pal Singh, Om; Suryaprakasa Rao, K.

    2005-01-01

    This paper presents the results of reliability analysis of Shutdown System (SDS) of Indian Prototype Fast Breeder Reactor. Reliability analysis carried out using Fault Tree Analysis predicts a value of 3.5 x 10 -8 /de for failure of shutdown function in case of global faults and 4.4 x 10 -8 /de for local faults. Based on 20 de/y, the frequency of shutdown function failure is 0.7 x 10 -6 /ry, which meets the reliability target, set by the Indian Atomic Energy Regulatory Board. The reliability is limited by Common Cause Failure (CCF) of actuation part of SDS and to a lesser extent CCF of electronic components. The failure frequency of individual systems is -3 /ry, which also meets the safety criteria. Uncertainty analysis indicates a maximum error factor of 5 for the top event unavailability

  5. Unobtrusive Indicators of Cultural Change: Neckties, Girdles, Marijuana, Garbage, Magazines, and Urban Sprawl.

    Science.gov (United States)

    Felson, Marcus

    1983-01-01

    Different types of time-series data sets can be used to identify cultural change and continuity. Indicators, including musical instruments, clothing, sporting goods, drugs, garbage, telephones, and magazines, are used to study social change since World War II. (Author/RM)

  6. The Berg Balance Scale has high intra- and inter-rater reliability but absolute reliability varies across the scale: a systematic review.

    Science.gov (United States)

    Downs, Stephen; Marquez, Jodie; Chiarelli, Pauline

    2013-06-01

    What is the intra-rater and inter-rater relative reliability of the Berg Balance Scale? What is the absolute reliability of the Berg Balance Scale? Does the absolute reliability of the Berg Balance Scale vary across the scale? Systematic review with meta-analysis of reliability studies. Any clinical population that has undergone assessment with the Berg Balance Scale. Relative intra-rater reliability, relative inter-rater reliability, and absolute reliability. Eleven studies involving 668 participants were included in the review. The relative intrarater reliability of the Berg Balance Scale was high, with a pooled estimate of 0.98 (95% CI 0.97 to 0.99). Relative inter-rater reliability was also high, with a pooled estimate of 0.97 (95% CI 0.96 to 0.98). A ceiling effect of the Berg Balance Scale was evident for some participants. In the analysis of absolute reliability, all of the relevant studies had an average score of 20 or above on the 0 to 56 point Berg Balance Scale. The absolute reliability across this part of the scale, as measured by the minimal detectable change with 95% confidence, varied between 2.8 points and 6.6 points. The Berg Balance Scale has a higher absolute reliability when close to 56 points due to the ceiling effect. We identified no data that estimated the absolute reliability of the Berg Balance Scale among participants with a mean score below 20 out of 56. The Berg Balance Scale has acceptable reliability, although it might not detect modest, clinically important changes in balance in individual subjects. The review was only able to comment on the absolute reliability of the Berg Balance Scale among people with moderately poor to normal balance. Copyright © 2013 Australian Physiotherapy Association. Published by .. All rights reserved.

  7. On the Simulation-Based Reliability of Complex Emergency Logistics Networks in Post-Accident Rescues.

    Science.gov (United States)

    Wang, Wei; Huang, Li; Liang, Xuedong

    2018-01-06

    This paper investigates the reliability of complex emergency logistics networks, as reliability is crucial to reducing environmental and public health losses in post-accident emergency rescues. Such networks' statistical characteristics are analyzed first. After the connected reliability and evaluation indices for complex emergency logistics networks are effectively defined, simulation analyses of network reliability are conducted under two different attack modes using a particular emergency logistics network as an example. The simulation analyses obtain the varying trends in emergency supply times and the ratio of effective nodes and validates the effects of network characteristics and different types of attacks on network reliability. The results demonstrate that this emergency logistics network is both a small-world and a scale-free network. When facing random attacks, the emergency logistics network steadily changes, whereas it is very fragile when facing selective attacks. Therefore, special attention should be paid to the protection of supply nodes and nodes with high connectivity. The simulation method provides a new tool for studying emergency logistics networks and a reference for similar studies.

  8. Effect of knee angle on neuromuscular assessment of plantar flexor muscles: A reliability study

    Science.gov (United States)

    Cornu, Christophe; Jubeau, Marc

    2018-01-01

    Introduction This study aimed to determine the intra- and inter-session reliability of neuromuscular assessment of plantar flexor (PF) muscles at three knee angles. Methods Twelve young adults were tested for three knee angles (90°, 30° and 0°) and at three time points separated by 1 hour (intra-session) and 7 days (inter-session). Electrical (H reflex, M wave) and mechanical (evoked and maximal voluntary torque, activation level) parameters were measured on the PF muscles. Intraclass correlation coefficients (ICC) and coefficients of variation were calculated to determine intra- and inter-session reliability. Results The mechanical measurements presented excellent (ICC>0.75) intra- and inter-session reliabilities regardless of the knee angle considered. The reliability of electrical measurements was better for the 90° knee angle compared to the 0° and 30° angles. Conclusions Changes in the knee angle may influence the reliability of neuromuscular assessments, which indicates the importance of considering the knee angle to collect consistent outcomes on the PF muscles. PMID:29596480

  9. On the Simulation-Based Reliability of Complex Emergency Logistics Networks in Post-Accident Rescues

    Science.gov (United States)

    Wang, Wei; Huang, Li; Liang, Xuedong

    2018-01-01

    This paper investigates the reliability of complex emergency logistics networks, as reliability is crucial to reducing environmental and public health losses in post-accident emergency rescues. Such networks’ statistical characteristics are analyzed first. After the connected reliability and evaluation indices for complex emergency logistics networks are effectively defined, simulation analyses of network reliability are conducted under two different attack modes using a particular emergency logistics network as an example. The simulation analyses obtain the varying trends in emergency supply times and the ratio of effective nodes and validates the effects of network characteristics and different types of attacks on network reliability. The results demonstrate that this emergency logistics network is both a small-world and a scale-free network. When facing random attacks, the emergency logistics network steadily changes, whereas it is very fragile when facing selective attacks. Therefore, special attention should be paid to the protection of supply nodes and nodes with high connectivity. The simulation method provides a new tool for studying emergency logistics networks and a reference for similar studies. PMID:29316614

  10. The relative and absolute reliability of the Functional Independence and Difficulty Scale in community-dwelling frail elderly Japanese people using long-term care insurance services.

    Science.gov (United States)

    Saito, Takashi; Izawa, Kazuhiro P; Watanabe, Shuichiro

    2017-06-01

    The newly developed Functional Independence and Difficulty Scale is a tool for assessing the performance of basic activities of daily living in terms of both independence and difficulty. The reliability of this new scale has not been assessed. The aim of this study was to examine the relative reliability and absolute reliability of the newly developed scale in community-dwelling frail elderly people in Japan. Participants were 47 community-dwelling elderly subjects (22 for assessing test-retest reliability and 25 for assessing inter-rater reliability). As relative reliability indices, intra-class correlation coefficients were used. From an absolute reliability perspective, we conducted Bland-Altman analysis and calculated the limit of agreement or minimal detectable change to determine the acceptable range of error. Intra-class correlation coefficients for test-retest and inter-rater reliability were 0.90 (P reliability was -5.2 to 1.8, representing an increase of over six points for improvement and a decrease of over two points for decline of basic activities of daily living ability. The minimal detectable change for inter-rater reliability was 3.7, indicating that a three-point difference might be existed between difference raters. The results of this study demonstrated that the FIDS appeared to be a reliable instrument for use in Japanese community-dwelling frail elderly people. While further research using a large and more diverse sample of participants is needed, our findings support the use of FIDS in clinical practice or clinical research targeting frail elderly Japanese people.

  11. Utilizing the social media data to validate 'climate change' indices

    Science.gov (United States)

    Molodtsova, T.; Kirilenko, A.; Stepchenkova, S.

    2013-12-01

    Reporting the observed and modeled changes in climate to public requires the measures understandable by the general audience. E.g., the NASA GISS Common Sense Climate Index (Hansen et al., 1998) reports the change in climate based on six practically observable parameters such as the air temperature exceeding the norm by one standard deviation. The utility of the constructed indices for reporting climate change depends, however, on an assumption that the selected parameters are felt and connected with the changing climate by a non-expert, which needs to be validated. Dynamic discussion of climate change issues in social media may provide data for this validation. We connected the intensity of public discussion of climate change in social networks with regional weather variations for the territory of the USA. We collected the entire 2012 population of Twitter microblogging activity on climate change topic, accumulating over 1.8 million separate records (tweets) globally. We identified the geographic location of the tweets and associated the daily and weekly intensity of twitting with the following parameters of weather for these locations: temperature anomalies, 'hot' temperature anomalies, 'cold' temperature anomalies, heavy rain/snow events. To account for non-weather related events we included the articles on climate change from the 'prestige press', a collection of major newspapers. We found that the regional changes in parameters of weather significantly affect the number of tweets published on climate change. This effect, however, is short-lived and varies throughout the country. We found that in different locations different weather parameters had the most significant effect on climate change microblogging activity. Overall 'hot' temperature anomalies had significant influence on climate change twitting intensity.

  12. Reliability parameters of distribution networks components

    Energy Technology Data Exchange (ETDEWEB)

    Gono, R.; Kratky, M.; Rusek, S.; Kral, V. [Technical Univ. of Ostrava (Czech Republic)

    2009-03-11

    This paper presented a framework for the retrieval of parameters from various heterogenous power system databases. The framework was designed to transform the heterogenous outage data in a common relational scheme. The framework was used to retrieve outage data parameters from the Czech and Slovak republics in order to demonstrate the scalability of the framework. A reliability computation of the system was computed in 2 phases representing the retrieval of component reliability parameters and the reliability computation. Reliability rates were determined using component reliability and global reliability indices. Input data for the reliability was retrieved from data on equipment operating under similar conditions, while the probability of failure-free operations was evaluated by determining component status. Anomalies in distribution outage data were described as scheme, attribute, and term differences. Input types consisted of input relations; transformation programs; codebooks; and translation tables. The system was used to successfully retrieve data from 7 distributors in the Czech Republic and Slovak Republic between 2000-2007. The database included 301,555 records. Data were queried using SQL language. 29 refs., 2 tabs., 2 figs.

  13. Development of ecological indicators of climate change based on lichen functional diversity

    OpenAIRE

    Matos, Paula Sofia Antunes

    2016-01-01

    Growing evidence shows us that climate has changed in the recent decades, and the scenario for the future will most likely worsen. A set of climate variables is being developed to monitor climate change, but this is not enough to keep track its effects on ecosystems. It’s imperative to understand and quantify how ecosystems functioning are affected by and respond to these changes, and ecological indicators based on biodiversity metrics are one of the tools to do this. The...

  14. Photovoltaic and Wind Turbine Integration Applying Cuckoo Search for Probabilistic Reliable Optimal Placement

    Directory of Open Access Journals (Sweden)

    R. A. Swief

    2018-01-01

    Full Text Available This paper presents an efficient Cuckoo Search Optimization technique to improve the reliability of electrical power systems. Various reliability objective indices such as Energy Not Supplied, System Average Interruption Frequency Index, System Average Interruption, and Duration Index are the main indices indicating reliability. The Cuckoo Search Optimization (CSO technique is applied to optimally place the protection devices, install the distributed generators, and to determine the size of distributed generators in radial feeders for reliability improvement. Distributed generator affects reliability and system power losses and voltage profile. The volatility behaviour for both photovoltaic cells and the wind turbine farms affect the values and the selection of protection devices and distributed generators allocation. To improve reliability, the reconfiguration will take place before installing both protection devices and distributed generators. Assessment of consumer power system reliability is a vital part of distribution system behaviour and development. Distribution system reliability calculation will be relayed on probabilistic reliability indices, which can expect the disruption profile of a distribution system based on the volatility behaviour of added generators and load behaviour. The validity of the anticipated algorithm has been tested using a standard IEEE 69 bus system.

  15. Power system reliability analysis using fault trees

    International Nuclear Information System (INIS)

    Volkanovski, A.; Cepin, M.; Mavko, B.

    2006-01-01

    The power system reliability analysis method is developed from the aspect of reliable delivery of electrical energy to customers. The method is developed based on the fault tree analysis, which is widely applied in the Probabilistic Safety Assessment (PSA). The method is adapted for the power system reliability analysis. The method is developed in a way that only the basic reliability parameters of the analysed power system are necessary as an input for the calculation of reliability indices of the system. The modeling and analysis was performed on an example power system consisting of eight substations. The results include the level of reliability of current power system configuration, the combinations of component failures resulting in a failed power delivery to loads, and the importance factors for components and subsystems. (author)

  16. Physical soil quality indicators for monitoring British soils

    Science.gov (United States)

    Corstanje, Ron; Mercer, Theresa G.; Rickson, Jane R.; Deeks, Lynda K.; Newell-Price, Paul; Holman, Ian; Kechavarsi, Cedric; Waine, Toby W.

    2017-09-01

    Soil condition or quality determines its ability to deliver a range of functions that support ecosystem services, human health and wellbeing. The increasing policy imperative to implement successful soil monitoring programmes has resulted in the demand for reliable soil quality indicators (SQIs) for physical, biological and chemical soil properties. The selection of these indicators needs to ensure that they are sensitive and responsive to pressure and change, e.g. they change across space and time in relation to natural perturbations and land management practices. Using a logical sieve approach based on key policy-related soil functions, this research assessed whether physical soil properties can be used to indicate the quality of British soils in terms of their capacity to deliver ecosystem goods and services. The resultant prioritised list of physical SQIs was tested for robustness, spatial and temporal variability, and expected rate of change using statistical analysis and modelling. Seven SQIs were prioritised: soil packing density, soil water retention characteristics, aggregate stability, rate of soil erosion, depth of soil, soil structure (assessed by visual soil evaluation) and soil sealing. These all have direct relevance to current and likely future soil and environmental policy and are appropriate for implementation in soil monitoring programmes.

  17. Physical soil quality indicators for monitoring British soils

    Directory of Open Access Journals (Sweden)

    R. Corstanje

    2017-09-01

    Full Text Available Soil condition or quality determines its ability to deliver a range of functions that support ecosystem services, human health and wellbeing. The increasing policy imperative to implement successful soil monitoring programmes has resulted in the demand for reliable soil quality indicators (SQIs for physical, biological and chemical soil properties. The selection of these indicators needs to ensure that they are sensitive and responsive to pressure and change, e.g. they change across space and time in relation to natural perturbations and land management practices. Using a logical sieve approach based on key policy-related soil functions, this research assessed whether physical soil properties can be used to indicate the quality of British soils in terms of their capacity to deliver ecosystem goods and services. The resultant prioritised list of physical SQIs was tested for robustness, spatial and temporal variability, and expected rate of change using statistical analysis and modelling. Seven SQIs were prioritised: soil packing density, soil water retention characteristics, aggregate stability, rate of soil erosion, depth of soil, soil structure (assessed by visual soil evaluation and soil sealing. These all have direct relevance to current and likely future soil and environmental policy and are appropriate for implementation in soil monitoring programmes.

  18. Selecting and applying indicators of ecosystem collapse for risk assessments.

    Science.gov (United States)

    Rowland, Jessica A; Nicholson, Emily; Murray, Nicholas J; Keith, David A; Lester, Rebecca E; Bland, Lucie M

    2018-03-12

    Ongoing ecosystem degradation and transformation are key threats to biodiversity. Measuring ecosystem change towards collapse relies on monitoring indicators that quantify key ecological processes. Yet little guidance is available on selecting and implementing indicators for ecosystem risk assessment. Here, we reviewed indicator use in ecological studies of decline towards collapse in marine pelagic and temperate forest ecosystems. We evaluated the use of indicator selection methods, indicator types (geographic distribution, abiotic, biotic), methods of assessing multiple indicators, and temporal quality of time series. We compared these ecological studies to risk assessments in the International Union for the Conservation of Nature Red List of Ecosystems (RLE), where indicators are used to estimate ecosystem collapse risk. We found that ecological studies and RLE assessments rarely reported how indicators were selected, particularly in terrestrial ecosystems. Few ecological studies and RLE assessments quantified ecosystem change with all three indicator types, and indicators types used varied between marine and terrestrial ecosystem. Several studies used indices or multivariate analyses to assess multiple indicators simultaneously, but RLE assessments did not, as RLE guidelines advise against them. Most studies and RLE assessments used time series spanning at least 30 years, increasing the chance of reliably detecting change. Limited use of indicator selection protocols and infrequent use of all three indicator types may hamper the ability to accurately detect changes. To improve the value of risk assessments for informing policy and management, we recommend using: (i) explicit protocols, including conceptual models, to identify and select indicators; (ii) a range of indicators spanning distributional, abiotic and biotic features; (iii) indices and multivariate analyses with extreme care until guidelines are developed; (iv) time series with sufficient data to

  19. Test-Retest Reliability of Isokinetic Knee Strength Measurements in Children Aged 8 to 10 Years.

    Science.gov (United States)

    Fagher, Kristina; Fritzson, Annelie; Drake, Anna Maria

    Isokinetic dynamometry is a useful tool to objectively assess muscle strength of children and adults in athletic and rehabilitative settings. This study examined test-retest reliability of isokinetic knee strength measurements in children aged 8 to 10 years and defined limits for the minimum difference (MD) in strength that indicates a clinically important change. Isokinetic knee strength measurements (using the Biodex System 4) in children will provide reliable results. Descriptive laboratory study. In 22 healthy children, 5 maximal concentric (CON) knee extensor (KE) and knee flexor (KF) contractions at 2 angular velocities (60 deg/s and 180 deg/s) and 5 maximal eccentric (ECC) KE/KF contractions at 60 deg/s were assessed 7 days apart. The intraclass correlation coefficient (ICC 2.1 ) was used to examine relative reliability, and the MD was calculated on the basis of standard error of measurement. ICCs for CON KE/KF peak torque measurements were fair to excellent (range, 0.49-0.81). The MD% values for CON KE and KF ranged from 31% to 37% at 60 deg/s and from 34% to 39% at 180 deg/s. ICCs in the ECC mode were good (range, 0.60-0.70), but associated MD% values were high (>50%). There was no systematic error for CON KE/KF and ECC KE strength measurements at 60 deg/s, but systematic error was found for all other measurements. The dynamometer provides a reliable analysis of isokinetic CON knee strength measurements at 60 deg/s in children aged 8 to 10 years. Measurements at 180 deg/s and in the ECC mode were not reliable, indicating a need for more familiarization prior to testing. The MD values may help clinicians to determine whether a change in knee strength is due to error or intervention.

  20. Sensitive Indicators of Zonal Stipa Species to Changing Temperature and Precipitation in Inner Mongolia Grassland, China

    Science.gov (United States)

    Lv, Xiaomin; Zhou, Guangsheng; Wang, Yuhui; Song, Xiliang

    2016-01-01

    Climate change often induces shifts in plant functional traits. However, knowledge related to sensitivity of different functional traits and sensitive indicator representing plant growth under hydrothermal change remains unclear. Inner Mongolia grassland is predicted to be one of the terrestrial ecosystems which are most vulnerable to climate change. In this study, we analyzed the response of four zonal Stipa species (S. baicalensis, S. grandis, S. breviflora, and S. bungeana) from Inner Mongolia grassland to changing temperature (control, increased 1.5, 2, 4, and 6°C), precipitation (decreased 30 and 15%, control, increased 15 and 30%) and their combined effects via climate control chambers. The relative change of functional traits in the unit of temperature and precipitation change was regarded as sensitivity coefficient and sensitive indicators were examined by pathway analysis. We found that sensitivity of the four Stipa species to changing temperature and precipitation could be ranked as follows: S. bungeana > S. grandis > S. breviflora > S. baicalensis. In particular, changes in leaf area, specific leaf area and root/shoot ratio could account for 86% of the changes in plant biomass in the four Stipa species. Also these three measurements were more sensitive to hydrothermal changes than the other functional traits. These three functional indicators reflected the combination of plant production capacity (leaf area), adaptive strategy (root/shoot ratio), instantaneous environmental effects (specific leaf area), and cumulative environmental effects (leaf area and root/shoot ratio). Thus, leaf area, specific leaf area and root/shoot ratio were chosen as sensitive indicators in response to changing temperature and precipitation for Stipa species. These results could provide the basis for predicting the influence of climate change on Inner Mongolia grassland based on the magnitude of changes in sensitive indicators. PMID:26904048

  1. Thermal properties and reliability of eutectic mixture of stearic acid-acetamide as phase change material for latent heat storage

    International Nuclear Information System (INIS)

    Ma, Guixiang; Han, Lipeng; Sun, Jinhe; Jia, Yongzhong

    2017-01-01

    Highlights: • The system of stearic acid-acetamide binary mixtures were studied as phase change material. • The eutectic mixtures featured low melting temperatures and high latent heats of fusion for latent heat storage. • Solid-liquid phase diagrams for the system were constructed. • Negligible change in stability after 500 heating/cooling cycles. - Abstract: The thermal properties and reliability of the stearic acid (SA) with acetamide (AC) binary mixture were characterized using differential scanning calorimetry (DSC), powder X-ray diffraction (XRD), thermogravimetric analysis (TG) and Fourier transform infrared spectroscopy (FT-IR). The phase diagrams for the SA-AC binary mixture with AC in the metastable and the stable form were constructed. The eutectic system with stable AC is 0.604 mol fraction SA, and displayed a melting temperature (T m ) of 64.55 °C and latent heat of melting (ΔH m ) of 193.87 J·g −1 . The eutectic systems with metastable AC are 0.397 and 0.604 mol fraction SA. The melting temperatures are 62.23 °C and 62.54 °C, and latent heats of fusion are 222.10 J·g −1 and 194.28 J·g −1 , respectively. Following accelerated thermal cycling tests, TG and FT-IR analysis indicate that the eutectic mixture (χ SA = 0.397) with the metastable AC has good cyclic and thermal stability. The results show that the SA-AC eutectic mixture use as phase change material (PCM) possess good prospect for low temperature thermal energy storage (TES) applications.

  2. Cumulative trauma disorders in the upper extremities: reliability of the postural and repetitive risk-factors index.

    Science.gov (United States)

    James, C P; Harburn, K L; Kramer, J F

    1997-08-01

    This study addresses test-retest reliability of the Postural and Repetitive Risk-Factors Index (PRRI) for work-related upper body injuries. This assessment was developed by the present authors. A repeated measures design was used to assess the test-retest reliability of a videotaped work-site assessment of subjects' movements. Ten heavy users of video display terminals (VDTs) from a local banking industry participated in the study. The 10 subjects' movements were videotaped for 2 hours on each of 2 separate days, while working on-site at their VDTs. The videotaped assessment, which utilized known postural risk factors for developing musculoskeletal disorder, pain, and discomfort in heavy VDT users (ie, repetitiveness, awkward and static postures, and contraction time), was called the PRRI. The videotaped movement assessments were subsequently analyzed in 15-minute sessions (five sessions per 2-hour videotape, which produced a total of 10 sessions over the 2 testing days), and each session was chosen randomly from the videotape. The subjects' movements were given a postural risk score according to the criteria in the PRRI. Each subject was therefore tested a total of 10 times (ie, 10 sessions), over two days. The maximum PRRI score for both sides of the body was 216 points. Reliability coefficients (RCs) for the PRRI scores were calculated, and the reliability of any one session met the minimum criterion for excellent reliability, which was .75. A two-way analysis of variance (ANOVA) confirmed that there was no statistically significant difference between sessions (p < .05). Calculations using the standard error of measurement (SEM) indicated that an individual tested once, on one day and with a PRRI score of 25, required a change of at least 8 points in order to be confident that a true change in score had occurred. The significant results from the reliability tests indicated that the PRRI was a reliable measurement tool that could be used by occupational health

  3. impact of climate change on reservoir reliability abstract résumé

    African Journals Online (AJOL)

    Prof. Adipala Ekwamu

    Research and observations indicate that increases in atmospheric carbon dioxide (CO2) are raising global and regional temperatures, and producing changes in other climate variables that drive the terrestrial hydrological cycle, most notably precipitation and potential evaporation. This paper presents results of a study ...

  4. Impedance Changes Indicate Proximal Ventriculoperitoneal Shunt Obstruction In Vitro.

    Science.gov (United States)

    Basati, Sukhraaj; Tangen, Kevin; Hsu, Ying; Lin, Hanna; Frim, David; Linninger, Andreas

    2015-12-01

    Extracranial cerebrospinal fluid (CSF) shunt obstruction is one of the most important problems in hydrocephalus patient management. Despite ongoing research into better shunt design, robust and reliable detection of shunt malfunction remains elusive. The authors present a novel method of correlating degree of tissue ingrowth into ventricular CSF drainage catheters with internal electrical impedance. The impedance based sensor is able to continuously monitor shunt patency using intraluminal electrodes. Prototype obstruction sensors were fabricated for in-vitro analysis of cellular ingrowth into a shunt under static and dynamic flow conditions. Primary astrocyte cell lines and C6 glioma cells were allowed to proliferate up to 7 days within a shunt catheter and the impedance waveform was observed. During cell ingrowth a significant change in the peak-to-peak voltage signal as well as the root-mean-square voltage level was observed, allowing the impedance sensor to potentially anticipate shunt malfunction long before it affects fluid drainage. Finite element modeling was employed to demonstrate that the electrical signal used to monitor tissue ingrowth is contained inside the catheter lumen and does not endanger tissue surrounding the shunt. These results may herald the development of "next generation" shunt technology that allows prediction of malfunction before it affects patient outcome.

  5. Changes in Social Exclusion Indicators and Psychological Distress Among Homeless People Over a 2.5-Year Period.

    Science.gov (United States)

    Van Straaten, Barbara; Rodenburg, Gerda; Van der Laan, Jorien; Boersma, Sandra N; Wolf, Judith R L M; Van de Mheen, Dike

    2018-01-01

    Although homelessness is inherently associated with social exclusion, homeless individuals are rarely included in conventional studies on social exclusion. Use of longitudinal survey data from a cohort study on homeless people in four major Dutch cities ( n  = 378) allowed to examine: changes in indicators of social exclusion among homeless people over a 2.5-year period after reporting to the social relief system, and associations between changes in indicators of social exclusion and changes in psychological distress. Multinomial logistic regression analysis was applied to investigate the associations between changes in indicators of social exclusion and changes in psychological distress. Improvements were found in various indicators of social exclusion, whereas financial debts showed no significant improvement. Changes in unmet care needs, health insurance, social support from family and relatedness to others were related to changes in psychological distress. This study demonstrated improvements in various indicators of social exclusion among homeless people over a period of 2.5 years, and sheds light on the concept of social exclusion in relation to homelessness.

  6. Reliability enhancement of portal frame structure by finite element synthesis

    International Nuclear Information System (INIS)

    Nakagiri, S.

    1989-01-01

    The stochastic finite element methods have been applied to the evaluation of structural response and reliability of uncertain structural systems. The structural reliability index of the advanced first-order second moment (AFOSM) method is a candidate of the measure of assessing structural safety and reliability. The reliability index can be evaluated when a baseline design of structures under interest is proposed and the covariance matrix of the probabilistic variables is acquired to represent uncertainties involved in the structure systems. The reliability index thus evaluated is not assured the largest one for the structure. There is left a possibility to enhance the structural reliability for the given covariance matrix by changing the baseline design. From such a viewpoint of structural optimization, some ideas have been proposed to maximize the reliability or to minimize the failure probability of uncertain structural systems. A method of changing the design is proposed to increase the reliability index from its baseline value to another desired value. The reliability index in this paper is calculated mainly by the method of Lagrange multiplier

  7. Reliability analysis for manual radiographic measures of rotatory subluxation or lateral listhesis in adult scoliosis.

    Science.gov (United States)

    Freedman, Brett A; Horton, William C; Rhee, John M; Edwards, Charles C; Kuklo, Timothy R

    2009-03-15

    Retrospective observational study. To define the inter- and intraobserver reliability of 3 measures of rotatory subluxation (RS) in adult scoliosis (AS). RS is a hallmark of AS. To accurately track this measure, one must know its reliability. Reliability testing has not been performed. PA 36" films of 29 AS patients were collected from one surgeon's practice. Three observers on 2 separate occasions measured all levels with >or=3-mm RS (60 levels, 360 measurements) on the convexity of the involved segment using 3 different techniques-midbody (MB), endplate (EP), and centroid (C). These data were then analyzed to determine the intraclass correlation coefficient (ICC) for inter- and intraobserver reliability. The thoracolumbar/lumbar curve (average 58 degrees ) was the major curve for the majority (62%) of patients. RS at L3/4 was most common (35%). The overall inter- and intraobserver reliability was good-excellent for all methods, but the centroid method consistently had the highest ICC. ICC correlated with observer experience. Moderate-severe arthritic change (present in 55%) and poor image quality (52%) decreased ICC, but it still remained good-excellent for each measure. The reproducibility coefficient for each measure was 4 mm for MB and 2.8 mm for C and EP. MB, EP, and C are reliable techniques to measure RS even in elderly arthritic spines, but the methods inherently produce different values for a given level. The centroid method is most reliable and least influenced by experience. The EP method is easy to perform and very reliable. Spine surgeons should pick their preferred method and apply it consistently. Changes >3 mm suggest RS progression. RS may be a useful measure in addition to Cobb angle in AS. Having defined measurement reliability, the role of RS progression in surgical indications and patient outcomes can be evaluated.

  8. Reliability of power system with open access

    International Nuclear Information System (INIS)

    Ehsani, A.; Ranjbar, A. M.; Fotuhi Firuzabad, M.; Ehsani, M.

    2003-01-01

    Recently, in many countries, electric utility industry is undergoing considerable changes in regard to its structure and regulation. It can be clearly seen that the thrust towards privatization and deregulation or re regulation of the electric utility industry will introduce numerous reliability problems that will require new criteria and analytical tools that recognize the residual uncertainties in the new environment. In this paper, different risks and uncertainties in competitive electricity markets are briefly introduced; the approach of customers, operators, planners, generation bodies and network providers to the reliability of deregulated system is studied; the impact of dispersed generation on system reliability is evaluated; and finally, the reliability cost/reliability worth issues in the new competitive environment are considered

  9. Reliability of coded data to identify earliest indications of cognitive decline, cognitive evaluation and Alzheimer's disease diagnosis: a pilot study in England.

    Science.gov (United States)

    Dell'Agnello, Grazia; Desai, Urvi; Kirson, Noam Y; Wen, Jody; Meiselbach, Mark K; Reed, Catherine C; Belger, Mark; Lenox-Smith, Alan; Martinez, Carlos; Rasmussen, Jill

    2018-03-22

    Evaluate the reliability of using diagnosis codes and prescription data to identify the timing of symptomatic onset, cognitive assessment and diagnosis of Alzheimer's disease (AD) among patients diagnosed with AD. This was a retrospective cohort study using the UK Clinical Practice Research Datalink (CPRD). The study cohort consisted of a random sample of 50 patients with first AD diagnosis in 2010-2013. Additionally, patients were required to have a valid text-field code and a hospital episode or a referral in the 3 years before the first AD diagnosis. The earliest indications of cognitive impairment, cognitive assessment and AD diagnosis were identified using two approaches: (1) using an algorithm based on diagnostic codes and prescription drug information and (2) using information compiled from manual review of both text-based and coded data. The reliability of the code-based algorithm for identifying the earliest dates of the three measures described earlier was evaluated relative to the comprehensive second approach. Additionally, common cognitive assessments (with and without results) were described for both approaches. The two approaches identified the same first dates of cognitive symptoms in 33 (66%) of the 50 patients, first cognitive assessment in 29 (58%) patients and first AD diagnosis in 43 (86%) patients. Allowing for the dates from the two approaches to be within 30 days, the code-based algorithm's success rates increased to 74%, 70% and 94%, respectively. Mini-Mental State Examination was the most commonly observed cognitive assessment in both approaches; however, of the 53 tests performed, only 19 results were observed in the coded data. The code-based algorithm shows promise for identifying the first AD diagnosis. However, the reliability of using coded data to identify earliest indications of cognitive impairment and cognitive assessments is questionable. Additionally, CPRD is not a recommended data source to identify results of cognitive

  10. Test-Retest Reliability of the Short-Form Survivor Unmet Needs Survey.

    Science.gov (United States)

    Taylor, Karen; Bulsara, Max; Monterosso, Leanne

    2018-01-01

    Reliable and valid needs assessment measures are important assessment tools in cancer survivorship care. A new 30-item short-form version of the Survivor Unmet Needs Survey (SF-SUNS) was developed and validated with cancer survivors, including hematology cancer survivors; however, test-retest reliability has not been established. The objective of this study was to assess the test-retest reliability of the SF-SUNS with a cohort of lymphoma survivors ( n = 40). Test-retest reliability of the SF-SUNS was conducted at two time points: baseline (time 1) and 5 days later (time 2). Test-retest data were collected from lymphoma cancer survivors ( n = 40) in a large tertiary cancer center in Western Australia. Intraclass correlation analyses compared data at time 1 (baseline) and time 2 (5 days later). Cronbach's alpha analyses were performed to assess the internal consistency at both time points. The majority (23/30, 77%) of items achieved test-retest reliability scores 0.45-0.74 (fair to good). A high degree of overall internal consistency was demonstrated (time 1 = 0.92, time 2 = 0.95), with scores 0.65-0.94 across subscales for both time points. Mixed test-retest reliability of the SF-SUNS was established. Our results indicate the SF-SUNS is responsive to the changing needs of lymphoma cancer survivors. Routine use of cancer survivorship specific needs-based assessments is required in oncology care today. Nurses are well placed to administer these assessments and provide tailored information and resources. Further assessment of test-retest reliability in hematology and other cancer cohorts is warranted.

  11. Effect of climate change on environmental flow indicators in the narew basin, poland.

    Science.gov (United States)

    Piniewski, Mikołaj; Laizé, Cédric L R; Acreman, Michael C; Okruszko, Tomasz; Schneider, Christof

    2014-01-01

    Environmental flows-the quantity of water required to maintain a river ecosystem in its desired state-are of particular importance in areas of high natural value. Water-dependent ecosystems are exposed to the risk of climate change through altered precipitation and evaporation. Rivers in the Narew basin in northeastern Poland are known for their valuable river and wetland ecosystems, many of them in pristine or near-pristine condition. The objective of this study was to assess changes in the environmental flow regime of the Narew river system, caused by climate change, as simulated by hydrological models with different degrees of physical characterization and spatial aggregation. Two models were assessed: the river basin scale model Soil and Water Assessment Tool (SWAT) and the continental model of water availability and use WaterGAP. Future climate change scenarios were provided by two general circulation models coupled with the A2 emission scenario: IPSL-CM4 and MIROC3.2. To assess the impact of climate change on environmental flows, a method based conceptually on the "range of variability" approach was used. The results indicate that the environmental flow regime in the Narew basin is subject to climate change risk, whose magnitude and spatial variability varies with climate model and hydrological modeling scale. Most of the analyzed sites experienced moderate impacts for the Generic Environmental Flow Indicator (GEFI), the Floodplain Inundation Indicator, and the River Habitat Availability Indicator. The consistency between SWAT and WaterGAP for GEFI was medium: in 55 to 66% of analyzed sites, the models suggested the same level of impact. Hence, we suggest that state-of-the-art, high-resolution, global- or continental-scale models, such as WaterGAP, could be useful tools for water management decision-makers and wetland conservation practitioners, whereas models such as SWAT should serve as a complementary tool for more specific, smaller-scale, local

  12. Reliability and minimal detectable change of a modified passive neck flexion test in patients with chronic nonspecific neck pain and asymptomatic subjects.

    Science.gov (United States)

    López-de-Uralde-Villanueva, Ibai; Acuyo-Osorio, Mario; Prieto-Aldana, María; La Touche, Roy

    2017-04-01

    The Passive Neck Flexion Test (PNFT) can diagnose meningitis and potential spinal disorders. Little evidence is available concerning the use of a modified version of the PNFT (mPNFT) in patients with chronic nonspecific neck pain (CNSNP). To assess the reliability of the mPNFT in subjects with and without CNSNP. The secondary objective was to assess the differences in the symptoms provoked by the mPNFT between these two populations. We used repeated measures concordance design for the main objective and cross-sectional design for the secondary objective. A total of 30 asymptomatic subjects and 34 patients with CNSNP were recruited. The following measures were recorded: the range of motion at the onset of symptoms (OS-mPNFT), the range of motion at the submaximal pain (SP-mPNFT), and evoked pain intensity on the mPNFT (VAS-mPNFT). Good to excellent reliability was observed for OS-mPNFT and SP-mPNFT in the asymptomatic group (intra-examiner reliability: 0.95-0.97; inter-examiner reliability: 0.86-0.90; intra-examiner test-retest reliability: 0.84-0.87). In the CNSNP group, a good to excellent reliability was obtained for the OS-mPNFT (intra-examiner reliability: 0.89-0.96; inter-examiner reliability: 0.83-0.86; intra-examiner test-retest reliability: 0.83-0.85) and the SP-PNFT (intra-examiner reliability: 0.94-0.98; inter-examiner reliability: 0.80-0.82; intra-examiner test-retest reliability: 0.88-0.91). The CNSNP group showed statistically significant differences in OS-mPNFT (t = 4.92; P reliable tool regardless of the examiner and the time factor. Patients with CNSNP have a decrease range of motion and more pain than asymptomatic subjects in the mPNFT. This exceeds the minimal detectable changes for OS-mPNFT and VAS-mPNFT. Copyright © 2017 Elsevier Ltd. All rights reserved.

  13. Visual-Haptic Integration: Cue Weights are Varied Appropriately, to Account for Changes in Haptic Reliability Introduced by Using a Tool

    OpenAIRE

    Chie Takahashi; Simon J Watt

    2011-01-01

    Tools such as pliers systematically change the relationship between an object's size and the hand opening required to grasp it. Previous work suggests the brain takes this into account, integrating visual and haptic size information that refers to the same object, independent of the similarity of the ‘raw’ visual and haptic signals (Takahashi et al., VSS 2009). Variations in tool geometry also affect the reliability (precision) of haptic size estimates, however, because they alter the change ...

  14. Reliability assurance for regulation of advanced reactors

    International Nuclear Information System (INIS)

    Fullwood, R.; Lofaro, R.; Samanta, P.

    1992-01-01

    The advanced nuclear power plants must achieve higher levels of safety than the first generation of plants. Showing that this is indeed true provides new challenges to reliability and risk assessment methods in the analysis of the designs employing passive and semi-passive protection. Reliability assurance of the advanced reactor systems is important for determining the safety of the design and for determining the plant operability. Safety is the primary concern, but operability is considered indicative of good and safe operation. this paper discusses several concerns for reliability assurance of the advanced design encompassing reliability determination, level of detail required in advanced reactor submittals, data for reliability assurance, systems interactions and common cause effects, passive component reliability, PRA-based configuration control system, and inspection, training, maintenance and test requirements. Suggested approaches are provided for addressing each of these topics

  15. Reliability assurance for regulation of advanced reactors

    International Nuclear Information System (INIS)

    Fullwood, R.; Lofaro, R.; Samanta, P.

    1991-01-01

    The advanced nuclear power plants must achieve higher levels of safety than the first generation of plants. Showing that this is indeed true provides new challenges to reliability and risk assessment methods in the analysis of the designs employing passive and semi-passive protection. Reliability assurance of the advanced reactor systems is important for determining the safety of the design and for determining the plant operability. Safety is the primary concern, but operability is considered indicative of good and safe operation. This paper discusses several concerns for reliability assurance of the advanced design encompassing reliability determination, level of detail required in advanced reactor submittals, data for reliability assurance, systems interactions and common cause effects, passive component reliability, PRA-based configuration control system, and inspection, training, maintenance and test requirements. Suggested approaches are provided for addressing each of these topics

  16. Generation reliability assessment in oligopoly power market using Monte Carlo simulation

    International Nuclear Information System (INIS)

    Haroonabadi, H.; Haghifam, M.R.

    2007-01-01

    This paper addressed issues regarding power generation reliability assessment (HLI) in deregulated power pool markets. Most HLI reliability evaluation methods are based on the loss of load (LOLE) approach which is among the most suitable indices to describe the level of generation reliability. LOLE refers to the time in which load is greater than the amount of available generation. While most reliability assessments deal only with power system constraints, this study considered HLI reliability assessment in an oligopoly power market using Monte Carlo simulation (MCS). It evaluated the sensitivity of the reliability index to different reserve margins and future margins. The reliability index was determined by intersecting the offer and demand curves of power plants and comparing them to other parameters. The paper described the fundamentals of an oligopoly power pool market and proposed an algorithm for HLI reliability assessment for such a market. The proposed method was assessed on the IEEE-Reliability Test System with satisfactory results. In all cases, generation reliability indices were evaluated with different reserve margins and various load levels. 19 refs., 7 figs., 1 appendix

  17. Macroscopic travel time reliability diagrams for freeway networks

    NARCIS (Netherlands)

    Tu, H.; Li, H.; Van Lint, J.W.C.; Knoop, V.L.; Sun, L.

    2013-01-01

    Travel time reliability is considered to be one of the key indicators of transport system performance. Knowledge of the mechanisms of travel time unreliability enables the derivation of explanatory models with which travel time reliability can be predicted and utilized in traffic management.

  18. Reliability of psychophysiological responses across multiple motion sickness stimulation tests

    Science.gov (United States)

    Stout, C. S.; Toscano, W. B.; Cowings, P. S.

    1995-01-01

    Although there is general agreement that a high degree of variability exists between subjects in their autonomic nervous system responses to motion sickness stimulation, very little evidence exists that examines the reproducibility of autonomic responses within subjects during motion sickness stimulation. Our objectives were to examine the reliability of autonomic responses and symptom levels across five testing occasions using the (1) final minute of testing, (2) change in autonomic response and the change in symptom level, and (3) strength of the relationship between the change in symptom level and the change in autonomic responses across the entire motion sickness test. The results indicate that, based on the final minute of testing, the autonomic responses of heart rate, blood volume pulse, and respiration rate are moderately stable across multiple tests. Changes in heart rate, blood volume pulse, respiration rate, and symptoms throughout the test duration are less stable across the tests. Finally, autonomic responses and symptom levels are significantly related across the entire motion sickness test.

  19. Photovoltaic and Wind Turbine Integration Applying Cuckoo Search for Probabilistic Reliable Optimal Placement

    OpenAIRE

    R. A. Swief; T. S. Abdel-Salam; Noha H. El-Amary

    2018-01-01

    This paper presents an efficient Cuckoo Search Optimization technique to improve the reliability of electrical power systems. Various reliability objective indices such as Energy Not Supplied, System Average Interruption Frequency Index, System Average Interruption, and Duration Index are the main indices indicating reliability. The Cuckoo Search Optimization (CSO) technique is applied to optimally place the protection devices, install the distributed generators, and to determine the size of ...

  20. Changes in a suite of indicators of extreme temperature and precipitation under 1.5 and 2 degrees warming

    Science.gov (United States)

    Aerenson, Travis; Tebaldi, Claudia; Sanderson, Ben; Lamarque, Jean-François

    2018-03-01

    Following the 2015 Paris agreement, the Intergovernmental Panel on Climate Change was tasked with assessing climate change impacts and mitigation options for a world that limits warming to 1.5 °C in a special report. To aid the scientific assessment process three low-warming ensembles were generated over the 21st century based on the Paris targets using NCAR-DOE community model, CESM1-CAM5. This study used those simulation results and computed ten extreme climate indices, from definitions created by the Expert Team on Climate Change Detection and Indices, to determine if the three different scenarios cause different intensity and frequency of extreme precipitation or temperature over the 21st century. After computing the indices, statistical tests were used to determine if significant changes affect their characteristics. It was found that at the grid point level significant changes emerge in all scenarios, for nearly all indices. The temperature indices show widespread significant change, while the behavior of precipitation indices reflects the larger role that internal variability plays, even by the end of the century. Nonetheless differences can be assessed, in substantial measure for many of these indices: changes in nearly all indices have a strong correlation to global mean temperature, so that scenarios and times with greater temperature change experience greater index changes for many regions. This is particularly true of the temperature-related indices, but can be assessed for some regions also for the indices related to precipitation intensity. These results thus show that even for scenarios that are separated by only half of a degree in global average temperature, the statistics of extremes are significantly different.

  1. Reliability engineering

    International Nuclear Information System (INIS)

    Lee, Chi Woo; Kim, Sun Jin; Lee, Seung Woo; Jeong, Sang Yeong

    1993-08-01

    This book start what is reliability? such as origin of reliability problems, definition of reliability and reliability and use of reliability. It also deals with probability and calculation of reliability, reliability function and failure rate, probability distribution of reliability, assumption of MTBF, process of probability distribution, down time, maintainability and availability, break down maintenance and preventive maintenance design of reliability, design of reliability for prediction and statistics, reliability test, reliability data and design and management of reliability.

  2. The Reliable Change Index (RCI) of the WHO-5 in primary prevention of mental disorders. A measurement-based pilot study in positive psychiatry

    DEFF Research Database (Denmark)

    Bech, Per; Lindberg, Lone; Moeller, Stine B

    2018-01-01

    with the removal of the stressor. We have focused on a measurement-based method to prevent the development of an adjustment disorder. AIM: The aim of this study has been to analyze from an ongoing Worklife Barometer Survey in which the World Health Organization Well-Being Scale (WHO-5) has been applied to prevent...... distress leading to an adjustment disorder. METHODS: Persons identified with a decrease of 15 points in their repeatedly WHO-5 ratings over three months were through a brief psychological intervention by experienced psychologists. The Reliable Change Index (RCI) was used to determine the clinically...... meaningful change in the WHO-5 ratings. RESULTS: Within the group who received the psychological intervention (N = 1338), 35% of the persons were identified by the RCI analysis to have developed a clinically reliable change in the WHO-5 at the time of the intervention. The remaining 65% of the persons...

  3. Assessment of the Reliability of Concrete Bridges

    DEFF Research Database (Denmark)

    Middleton, C. R.; Thoft-Christensen, Palle

    Although there has been a considerable amount of research into different aspects of concrete bridge reliability, it has still not been widely adopted in professional practice other than in the development and calibration of codes. This situation appears to be changing as there has been a signific......Although there has been a considerable amount of research into different aspects of concrete bridge reliability, it has still not been widely adopted in professional practice other than in the development and calibration of codes. This situation appears to be changing as there has been...... adopted to assist in achieving this goal. Rather than review the specific research on this subject this paper examines a number of key issues related to the practical application of reliability analysis to the assessment of concrete bridges....

  4. Inter-examiner reliability of a standardized Ultra-sonographic method for classification of changes related to supraspinatus tendinopathy – a pilot study

    DEFF Research Database (Denmark)

    Larsen, Camilla Marie; Ingwersen, Kim Gordon; Hjarnbæk, John

    2015-01-01

    Inter-examiner reliability of a standardized Ultra-sonographic method for classification of changes related to supraspinatus tendinopathy – a pilot study Ingwersen KG1, 2, Hjarbaek J3, Eshøj H1, Larsen CM1, 4, Vobbe J5, Juul-Kristensen B1, 6 1Institute of Sports Science and Clinical Biomechanics......, University of Southern Denmark, Odense, Denmark. 2Physiotherapy Department, Hospital Lillebaelt, Vejle Hospital, Vejle, Denmark 3Department of Radiology, Musculoskeletal section, Odense University Hospital, Odense, Denmark 4Health Sciences Research Centre, University College Lillebaelt, Odense Denmark 5...... athletes. For optimizing rehabilitation to the different stages of tendinopathy (1) ultra-sonography (US) may be used. Reliability of such method for RT is lacking. Aims. To develop and test inter-examiner reliability of US for classifying RT. Materials and Methods. A three-phased standardized protocol...

  5. Soil and periphyton indicators of anthropogenic water-quality changes in a rainfall-driven wetland

    Science.gov (United States)

    McCormick, P.V.

    2011-01-01

    Surface soils and periphyton communities were sampled across an oligotrophic, soft-water wetland to document changes associated with pulsed inputs of nutrient- and mineral-rich canal drainage waters. A gradient of canal-water influence was indicated by the surface-water specific conductance, which ranged between 743 and 963 ??S cm-1 in the canals to as low as 60 ??S cm-1 in the rainfall-driven wetland interior. Changes in soil chemistry and periphyton taxonomic composition across this gradient were described using piecewise regressions models. The greatest increase in soil phosphorus (P) concentration occurred at sites closest to the canal while soil mineral (sulfur, calcium) concentrations increased most rapidly at the lower end of the gradient. Multiple periphyton shifts occurred at the lower end of the gradient and included; (1) a decline in desmids and non-desmid filamentous chlorophytes, and their replacement by a diatom-dominated community; (2) the loss of soft-water diatom indicator species and their replacement by hard-water species. Increased dominance by cyanobacteria and eutrophic diatom indicators occurred closer to the canals. Soil and periphyton changes indicated four zones of increasing canal influence across the wetland: (1) a zone of increasing mineral concentrations where soft-water taxa remained dominant; (2) a transition towards hard-water, oligotrophic diatoms as mineral concentrations increased further; (3) a zone of dominance by these hard-water species; (4) a zone of rapidly increasing P concentrations and dominance by eutrophic taxa. In contrast to conclusions drawn from routine water-chemistry monitoring, measures of chemical and biological change presented here indicate that most of this rainfall-driven peatland receives some influence from canal discharges. These changes are multifaceted and induced by shifts in multiple chemical constituents. ?? 2010 US Government.

  6. Test-retest reliability and four-week changes in cardiopulmonary fitness in stroke patients: evaluation using a robotics-assisted tilt table.

    Science.gov (United States)

    Saengsuwan, Jittima; Berger, Lucia; Schuster-Amft, Corina; Nef, Tobias; Hunt, Kenneth J

    2016-09-06

    Exercise testing devices for evaluating cardiopulmonary fitness in patients with severe disability after stroke are lacking, but we have adapted a robotics-assisted tilt table (RATT) for cardiopulmonary exercise testing (CPET). Using the RATT in a sample of patients after stroke, this study aimed to investigate test-retest reliability and repeatability of CPET and to prospectively investigate changes in cardiopulmonary outcomes over a period of four weeks. Stroke patients with all degrees of disability underwent 3 separate CPET sessions: 2 tests at baseline (TB1 and TB2) and 1 test at follow up (TF). TB1 and TB2 were at least 24 h apart. TB2 and TF were 4 weeks apart. A RATT equipped with force sensors in the thigh cuffs, a work rate estimation algorithm and a real-time visual feedback system was used to guide the patients' exercise work rate during CPET. Test-retest reliability and repeatability of CPET variables were analysed using paired t-tests, the intraclass correlation coefficient (ICC), the coefficient of variation (CoV), and Bland and Altman limits of agreement. Changes in cardiopulmonary fitness during four weeks were analysed using paired t-tests. Seventeen sub-acute and chronic stroke patients (age 62.7 ± 10.4 years [mean ± SD]; 8 females) completed the test sessions. The median time post stroke was 350 days. There were 4 severely disabled, 1 moderately disabled and 12 mildly disabled patients. For test-retest, there were no statistically significant differences between TB1 and TB2 for most CPET variables. Peak oxygen uptake, peak heart rate, peak work rate and oxygen uptake at the ventilatory anaerobic threshold (VAT) and respiratory compensation point (RCP) showed good to excellent test-retest reliability (ICC 0.65-0.94). For all CPET variables, CoV was 4.1-14.5 %. The mean difference was close to zero in most of the CPET variables. There were no significant changes in most cardiopulmonary performance parameters during the 4-week period

  7. Criteria for the Evaluation and Selection of Radiation-Induced Metabolic Changes as Biochemical Indicators of Radiation Damage

    Energy Technology Data Exchange (ETDEWEB)

    Altman, K. I. [Departments of Experimental Radiology, Radiation Biology, Biophysics and Biochemistry, University of Rochester, School of Medicine and Dentistry, Rochester, NY (United States)

    1971-03-15

    There are several reasons which prompt a search for suitable biochemical indicators of radiation damage in man. Perhaps the most compelling of these reasons is the urgent need for estimates of exposure doses in cases of accidental exposures of human subjects to ionizing radiations under conditions which preclude a reliable assessment of the exposure dose by the usual physical means. At worst, a biochemical estimate of the dose would provide an independent means of obtaining information otherwise based solely on physical considerations and assumptions. In addition, a biochemical estimate of radiation injury may also, under ideal circumstances, serve as a guide to the attending physician in chosing the type of therapy most efficacious and least likely to lead to complications in the near as well as more distant future. The availability of biochemical indicators capable of revealing with some degree of accuracy the impairment of function of a particular organ would be a helpful adjunct in making decisions concerning the therapeutic approach to be adopted. The latter aspect would be of considerable interest in acute, accidental radiation exposures since under these circumstances radiation exposures are frequently of the partial-body type. An estimate of radiation injury by means of biochemical indicators should also prove useful in cases of protracted or chronic exposures to radiation, the source of which may be either external or internal. The use of biochemical indicators under these conditions of radiation exposure may, in general, aid 'case-finding' efforts and, in a more specific way, may help in pin-pointing discrete organ dysfunctions. In evaluating the suitability of radiation-induced metabolic changes for application as biochemical indicators of radiation damage, the following general criteria may be set forth: (1) the biochemical response to irradiation must be dose-dependent within a certain, sufficiently wide range in order to be useful; (2) the sensitivity

  8. Validity and Reliability of 10-Hz Global Positioning System to Assess In-line Movement and Change of Direction.

    Science.gov (United States)

    Nikolaidis, Pantelis T; Clemente, Filipe M; van der Linden, Cornelis M I; Rosemann, Thomas; Knechtle, Beat

    2018-01-01

    The objectives of the present study were to examine the validity and reliability of the 10 Hz Johan GPS unit in assessing in-line movement and change of direction. The validity was tested against the criterion measure of 200 m track-and-field (track-and-field athletes, n = 8) and 20 m shuttle run endurance test (female soccer players, n = 20). Intra-unit and inter-unit reliability was tested by intra-class correlation coefficient (ICC) and coefficient of variation (CV), respectively. An analysis of variance examined differences between the GPS measurement and five laps of 200 m at 15 km/h, and t -test examined differences between the GPS measurement and 20 m shuttle run endurance test. The difference between the GPS measurement and 200 m distance ranged from -0.13 ± 3.94 m (95% CI -3.42; 3.17) in the first lap to 2.13 ± 2.64 m (95% CI -0.08; 4.33) in the fifth lap. A good intra-unit reliability was observed in 200 m (ICC = 0.833, 95% CI 0.535; 0.962). Inter-unit CV ranged from 1.31% (fifth lap) to 2.20% (third lap). The difference between the GPS measurement and 20 m shuttle run endurance test ranged from 0.33 ± 4.16 m (95% CI -10.01; 10.68) in 11.5 km/h to 9.00 ± 5.30 m (95% CI 6.44; 11.56) in 8.0 km/h. A moderate intra-unit reliability was shown in the second and third stage of the 20 m shuttle run endurance test (ICC = 0.718, 95% CI 0.222;0.898) and good reliability in the fifth, sixth, seventh and eighth (ICC = 0.831, 95% CI -0.229;0.996). Inter-unit CV ranged from 2.08% (11.5 km/h) to 3.92% (8.5 km/h). Based on these findings, it was concluded that the 10 Hz Johan system offers an affordable valid and reliable tool for coaches and fitness trainers to monitor training and performance.

  9. The Achievement of Therapeutic Objectives Scale: Interrater Reliability and Sensitivity to Change in Short-Term Dynamic Psychotherapy and Cognitive Therapy

    Science.gov (United States)

    Valen, Jakob; Ryum, Truls; Svartberg, Martin; Stiles, Tore C.; McCullough, Leigh

    2011-01-01

    This study examined interrater reliability and sensitivity to change of the Achievement of Therapeutic Objectives Scale (ATOS; McCullough, Larsen, et al., 2003) in short-term dynamic psychotherapy (STDP) and cognitive therapy (CT). The ATOS is a process scale originally developed to assess patients' achievements of treatment objectives in STDP,…

  10. High-reliability health care: getting there from here.

    Science.gov (United States)

    Chassin, Mark R; Loeb, Jerod M

    2013-09-01

    Despite serious and widespread efforts to improve the quality of health care, many patients still suffer preventable harm every day. Hospitals find improvement difficult to sustain, and they suffer "project fatigue" because so many problems need attention. No hospitals or health systems have achieved consistent excellence throughout their institutions. High-reliability science is the study of organizations in industries like commercial aviation and nuclear power that operate under hazardous conditions while maintaining safety levels that are far better than those of health care. Adapting and applying the lessons of this science to health care offer the promise of enabling hospitals to reach levels of quality and safety that are comparable to those of the best high-reliability organizations. We combined the Joint Commission's knowledge of health care organizations with knowledge from the published literature and from experts in high-reliability industries and leading safety scholars outside health care. We developed a conceptual and practical framework for assessing hospitals' readiness for and progress toward high reliability. By iterative testing with hospital leaders, we refined the framework and, for each of its fourteen components, defined stages of maturity through which we believe hospitals must pass to reach high reliability. We discovered that the ways that high-reliability organizations generate and maintain high levels of safety cannot be directly applied to today's hospitals. We defined a series of incremental changes that hospitals should undertake to progress toward high reliability. These changes involve the leadership's commitment to achieving zero patient harm, a fully functional culture of safety throughout the organization, and the widespread deployment of highly effective process improvement tools. Hospitals can make substantial progress toward high reliability by undertaking several specific organizational change initiatives. Further research

  11. Preparing for climate change regulation : an assessment of the current state of date reliability in the Canadian electrical industry

    International Nuclear Information System (INIS)

    Schuh, C.

    2003-01-01

    This presentation provided an overview of current Canadian greenhouse gas (GHG) reporting requirements, predictions about GHG regulations, and the current state of GHGs data reliability in the Canadian electrical industry. The author argued that while potential management strategies are necessary, they are not sufficient to meet Kyoto or similar types of initiatives because they do not provide incentives for reductions, they do not establish accountability, nor do they encourage reliable data. It was predicted that the first climate change regulation will be a sectoral agreement enacted at the federal/provincial level. It was also predicted that future regulations will include a requirement to report GHG emissions in a reliable manner and that regulators will use the data to track performance. The final prediction was that the onus will be on the companies to prove that the data is reliable as regulators will have limited resources to check the data. It was noted that the current state of data is not suitable for analytical testing because of a lack of clear definitions, a lack of industry comparison, inability to compare between companies, inability to compare between different types of power generation, and the inability to compare between years. It was suggested that data reliability could be improved by having the regulators review and monitor the reported data, or by having a third party review and provide assurance on the reported data. It was concluded that there will have to be agreement at the industry level on common measurement and calculation methodology, as well as an agreement on a common scope of reporting. 4 figs

  12. Changes of indicators of high-speed and high-speed and power preparedness at volleyball players of 12–13 years old

    Directory of Open Access Journals (Sweden)

    Oleg Shevchenko

    2016-04-01

    Full Text Available Purpose: to define changes of indicators of high-speed and high-speed and power preparedness of volleyball players of 12–13 years old. Material & Methods: the test exercises, which are recommended by the training program of CYSS on volleyball, were used for the definition of the level of development of high-speed and high-speed and power abilities of volleyball players. 25 young volleyball players from the group of the previous basic preparation took part in the experiment. Sports experience of sportsmen is 3–4 years. The analysis of scientifically-methodical literature, pedagogical testing, pedagogical experiment, methods of mathematical statistics were carried out. Results: the analyzed level of high-speed and high-speed and power abilities of volleyball players. Conclusions: the results had reliable changes (t=2,2–2,4 at р<0,05 of the level of high-speed and high-speed and power abilities of volleyball players of 12–13years old in the experimental group at the end of the experiment, except run on 30 m that demonstrates a positive influence of application of special exercises in the educational-training process.

  13. Cost-effective solutions to maintaining smart grid reliability

    Science.gov (United States)

    Qin, Qiu

    As the aging power systems are increasingly working closer to the capacity and thermal limits, maintaining an sufficient reliability has been of great concern to the government agency, utility companies and users. This dissertation focuses on improving the reliability of transmission and distribution systems. Based on the wide area measurements, multiple model algorithms are developed to diagnose transmission line three-phase short to ground faults in the presence of protection misoperations. The multiple model algorithms utilize the electric network dynamics to provide prompt and reliable diagnosis outcomes. Computational complexity of the diagnosis algorithm is reduced by using a two-step heuristic. The multiple model algorithm is incorporated into a hybrid simulation framework, which consist of both continuous state simulation and discrete event simulation, to study the operation of transmission systems. With hybrid simulation, line switching strategy for enhancing the tolerance to protection misoperations is studied based on the concept of security index, which involves the faulted mode probability and stability coverage. Local measurements are used to track the generator state and faulty mode probabilities are calculated in the multiple model algorithms. FACTS devices are considered as controllers for the transmission system. The placement of FACTS devices into power systems is investigated with a criterion of maintaining a prescribed level of control reconfigurability. Control reconfigurability measures the small signal combined controllability and observability of a power system with an additional requirement on fault tolerance. For the distribution systems, a hierarchical framework, including a high level recloser allocation scheme and a low level recloser placement scheme, is presented. The impacts of recloser placement on the reliability indices is analyzed. Evaluation of reliability indices in the placement process is carried out via discrete event

  14. Reliability of Autonomic Responses and Malaise Across Multiple Motion Sickness Stimulation Tests

    Science.gov (United States)

    Stout, Cynthia S.; Toscano, William B.; Cowings, Patricia S.

    1993-01-01

    There is general agreement that a high degree of variability exists between subjects in their autonomic nervous system responses to motion sickness stimulation. Additionally, a paucity of data exists that examines the variability within an individual across repeated motion sickness tests. Investigators have also examined the relationship of autonomic responses to motion sickness development. These investigations have used analyses at discrete points in time to describe this relationship. This approach fails to address the time course of autonomic responses and malaise development throughout the motion sickness test. Our objectives were to examine the reliability of autonomic responses and malaise using the final minute of the motion sickness test across five testing occasions, to examine the reliability of the change in autonomic responses and the change in malaise across five testing occasions, and to examine the relationship between changes in autonomic responses and changes in malaise level across the entire motion sickness test. Our results indicate that, based on the final minute of testing, the autonomic responses of heart rate, blood volume pulse, and respiration rate are moderately stable across multiple tests. Changes in heart rate, blood volume pulse, respiration rate, and malaise throughout the test duration were less stable across the tests. We attribute this instability to variations in individual susceptibility and the error associated with estimating a measure of autonomic gain.

  15. Long Series of GNSS Integrated Precipitable Water as a Climate Change Indicator

    Directory of Open Access Journals (Sweden)

    Kruczyk Michał

    2015-12-01

    Full Text Available This paper investigates information potential contained in tropospheric delay product for selected International GNSS Service (IGS stations in climatologic research. Long time series of daily averaged Integrated Precipitable Water (IPW can serve as climate indicator. The seasonal model of IPW change has been adjusted to the multi-year series (by the least square method. Author applied two modes: sinusoidal and composite (two or more oscillations. Even simple sinusoidal seasonal model (of daily IPW values series clearly represents diversity of world climates. Residuals in periods from 10 up to 17 years are searched for some long-term IPW trend – self-evident climate change indicator. Results are ambiguous: for some stations or periods IPW trends are quite clear, the following years (or the other station not visible. Method of fitting linear trend to IPW series does not influence considerably the value of linear trend. The results are mostly influenced by series length, completeness and data (e.g. meteorological quality. The longer and more homogenous IPW series, the better chance to estimate the magnitude of climatologic IPW changes.

  16. Episodic memory change in late adulthood: generalizability across samples and performance indices.

    Science.gov (United States)

    Dixon, Roger A; Wahlin, Ake; Maitland, Scott B; Hultsch, David F; Hertzog, Christopher; Bäckman, Lars

    2004-07-01

    Younger adults recall more information from episodic memory tasks than do older adults. Because longitudinal studies are rare and often incompatible, the extent of actual late-life memory change is not well established. We assemble two different longitudinal samples of normal older adults, each of which is tested twice at a 3-year interval, using a large battery of episodic memory indicators. Together, two-wave data from both the Victoria Longitudinal Study in Canada (n = 400) and the Kungsholmen Project in Sweden (n = 168) cover a 40-year span of adulthood, ranging from 54 to 94 years of age. Principal memory tasks include categorizable word lists, story recall, and random word lists, as well as indicators of cognitive support. Overall, an examination of performance on sets of common and complementary episodic tasks reveals that, for both samples, actual 3-year changes are modest and that, when decline occurs, it is gradual. The exception-greater decline for more supported tasks-suggests that these may be especially sensitive to late-life changes.

  17. Reliability of solid-state lighting electrical drivers subjected to WHTOL accelerated aging

    Energy Technology Data Exchange (ETDEWEB)

    Lall, Pradeep; Sakalauku, Peter; Davis, Lynn

    2014-05-27

    An investigation of a solid-state lighting (SSL) luminaire with the focus on the electronic driver which has been exposed to a standard wet hot temperature operating life (WHTOL) of 85% RH and 85°C in order to assess reliability of prolonged exposer to a harsh environment has been conducted. SSL luminaires are beginning introduced as head lamps in some of today's luxury automobiles and may also be fulfilling a variety of important outdoor applications such as overhead street lamps, traffic signals and landscape lighting. SSL luminaires in these environments are almost certain to encounter excessive moisture from humidity and high temperatures for a persistent period of time. The lack of accelerated test methods for LEDs to assess long-term reliability prior to introduction into the marketplace, a need for SSL physics based PHM modeling indicators for assessment and prediction of LED life, as well as the U.S. Department of Energy's R&D roadmap to replace todays lighting with SSL luminaires makes it important to increase the understanding of the reliability of SSL devices, specifically, in harsh environment applications. In this work, a set of SSL electrical drivers were investigated to determine failure mechanisms that occur during prolonged harsh environment applications. Each driver consists of four aluminum electrolytic capacitors (AECs) of three different types and was considered the weakest component inside the SSL electrical driver. The reliability of the electrical driver was assessed by monitoring the change in capacitance and the change in equivalent series resistance for each AEC, as well as monitoring the luminous flux of the SSL luminaire or the output of the electrical driver. The luminous flux of a pristine SSL electrical driver was also monitored in order to detect minute changes in the electrical drivers output and to aid in the investigation of the SSL luminaires reliability. The failure mechanisms of the electrical drivers have been

  18. Validity and Reliability of a Portable Balance Tracking System, BTrackS, in Older Adults.

    Science.gov (United States)

    Levy, Susan S; Thralls, Katie J; Kviatkovsky, Shiloah A

    Falls are the leading cause of disability, injury, hospital admission, and injury-related death among older adults. Balance limitations have consistently been identified as predictors of falls and increased fall risk. Field measures of balance are limited by issues of subjectivity, ceiling effects, and low sensitivity to change. The gold standard for measuring balance is the force plate; however, its field use is untenable due to high cost and lack of portability. Thus, a critical need is observed for valid objective field measures of balance to accurately assess balance and identify limitations over time. The purpose of this study was to examine the concurrent validity and 3-day test-retest reliability of Balance Tracking System (BTrackS) in community-dwelling older adults. Minimal detectable change values were also calculated to reflect changes in balance beyond measurement error. Postural sway data were collected from community-dwelling older adults (N = 49, mean [SD] age = 71.3 [7.3] years) with a force plate and BTrackS in multitrial eyes open (EO) and eyes closed (EC) static balance conditions. Force sensors transmitted BTrackS data via a USB to a computer running custom software. Three approaches to concurrent validity were taken including calculation of Pearson product moment correlation coefficients, repeated-measures ANOVAs, and Bland-Altman plots. Three-day test-retest reliability of BTrackS was examined in a second sample of 47 community-dwelling older adults (mean [SD] age = 75.8 [7.7] years) using intraclass correlation coefficients and MDC values at 95% CI (MDC95) were calculated. BTrackS demonstrated good validity using Pearson product moment correlations (r > 0.90). Repeated-measures ANOVA and Bland-Altman plots indicated some BTrackS bias with center of pressure (COP) values higher than FP COP values in the EO (mean [SD] bias = 4.0 [6.8]) and EC (mean [SD] bias = 9.6 [12.3]) conditions. Test-retest reliability using intraclass correlation

  19. Evaluation of the influence of change in heart rate on left ventricular diastolic function indices

    International Nuclear Information System (INIS)

    Kimura, Motomasa; Yamagishi, Hiroaki; Seino, Yasuyuki; Odano, Ikuo; Sakai, Kunio; Yamamoto, Tomohiko; Tsuda, Takashi

    1988-01-01

    In order to assess the influence of change in heart rate on left ventricular diastolic function indices, ECG gated cardiac pool study was performed in 6 patients with implanted programmable AAI pacemakers. Heart rate was changed by atrial pacing from 50 to 120 beats/min, every 10 beats/min. The filling fraction during first third of diastole (1/3FF), the peak filling rate (PFR), mean first third filling rate (1/3FR-mean) and early filling volume ratio (%EFV), being used as the indices of left ventricular diastolic performance, were assessed. In accordance with increase in heart rate, 1/3FF decreased significantly. PFR were fairly stable from 50 to 80 beats/min, but increased significantly from 90 to 120 beats/min. 1/3FR-mean and %EFV did not change significantly, but 1/3FR-mean showed decreasing tendency and %EFV showed increasing tendency as the heart rate was increased. %EFV was more changeable index than other indices among clinical cases. These results indicate that PFR and 1/3FR-mean were appropriate diastolic phase indices at rest. (author)

  20. Empirical Productivity Indices and Indicators

    NARCIS (Netherlands)

    B.M. Balk (Bert)

    2016-01-01

    textabstractThe empirical measurement of productivity change (or difference) by means of indices and indicators starts with the ex post profit/loss accounts of a production unit. Key concepts are profit, leading to indicators, and profitability, leading to indices. The main task for the productivity

  1. Classifier Fusion With Contextual Reliability Evaluation.

    Science.gov (United States)

    Liu, Zhunga; Pan, Quan; Dezert, Jean; Han, Jun-Wei; He, You

    2018-05-01

    Classifier fusion is an efficient strategy to improve the classification performance for the complex pattern recognition problem. In practice, the multiple classifiers to combine can have different reliabilities and the proper reliability evaluation plays an important role in the fusion process for getting the best classification performance. We propose a new method for classifier fusion with contextual reliability evaluation (CF-CRE) based on inner reliability and relative reliability concepts. The inner reliability, represented by a matrix, characterizes the probability of the object belonging to one class when it is classified to another class. The elements of this matrix are estimated from the -nearest neighbors of the object. A cautious discounting rule is developed under belief functions framework to revise the classification result according to the inner reliability. The relative reliability is evaluated based on a new incompatibility measure which allows to reduce the level of conflict between the classifiers by applying the classical evidence discounting rule to each classifier before their combination. The inner reliability and relative reliability capture different aspects of the classification reliability. The discounted classification results are combined with Dempster-Shafer's rule for the final class decision making support. The performance of CF-CRE have been evaluated and compared with those of main classical fusion methods using real data sets. The experimental results show that CF-CRE can produce substantially higher accuracy than other fusion methods in general. Moreover, CF-CRE is robust to the changes of the number of nearest neighbors chosen for estimating the reliability matrix, which is appealing for the applications.

  2. Reliability of Power Units in Poland and the World

    OpenAIRE

    Józef Paska

    2015-01-01

    One of a power system’s subsystems is the generation subsystem consisting of power units, the reliability of which to a large extent determines the reliability of the power system and electricity supply to consumers. This paper presents definitions of the basic indices of power unit reliability used in Poland and in the world. They are compared and analysed on the basis of data published by the Energy Market Agency (Poland), NERC (North American Electric Reliability Corporation – USA), ...

  3. A Reliability-Oriented Design Method for Power Electronic Converters

    DEFF Research Database (Denmark)

    Wang, Huai; Zhou, Dao; Blaabjerg, Frede

    2013-01-01

    Reliability is a crucial performance indicator of power electronic systems in terms of availability, mission accomplishment and life cycle cost. A paradigm shift in the research on reliability of power electronics is going on from simple handbook based calculations (e.g. models in MIL-HDBK-217F h...... and reliability prediction models are provided. A case study on a 2.3 MW wind power converter is discussed with emphasis on the reliability critical component IGBT modules....

  4. 76 FR 71011 - Reliability Technical Conference Agenda

    Science.gov (United States)

    2011-11-16

    ... process? Do you support the exemption process changes identified by the RTOs or other entities in comments... reliability plans? b. Do you support the exemption process changes identified by the RTOs or other entities in...

  5. New endoscopic indicator of esophageal achalasia: "pinstripe pattern".

    Directory of Open Access Journals (Sweden)

    Hitomi Minami

    Full Text Available Endoscopic diagnosis of esophageal achalasia lacking typical endoscopic features can be extremely difficult. The aim of this study was to identify simple and reliable early indicator of esophageal achalasia.This single-center retrospective study included 56 cases of esophageal achalasia without previous treatment. As a control, 60 non-achalasia subjects including reflux esophagitis and superficial esophageal cancer were also included in this study. Endoscopic findings were evaluated according to Descriptive Rules for Achalasia of the Esophagus as follows: (1 esophageal dilatation, (2 abnormal retention of liquid and/or food, (3 whitish change of the mucosal surface, (4 functional stenosis of the esophago-gastric junction, and (5 abnormal contraction. Additionally, the presence of the longitudinal superficial wrinkles of esophageal mucosa, "pinstripe pattern (PSP" was evaluated endoscopically. Then, inter-observer diagnostic agreement was assessed for each finding.The prevalence rates of the above-mentioned findings (1-5 were 41.1%, 41.1%, 16.1%, 94.6%, and 43.9%, respectively. PSP was observed in 60.7% of achalasia, while none of the control showed positivity for PSP. PSP was observed in 26 (62.5% of 35 cases with shorter history < 10 years, which usually lacks typical findings such as severe esophageal dilation and tortuosity. Inter-observer agreement level was substantial for food/liquid remnant (k = 0.6861 and PSP (k = 0.6098, and was fair for abnormal contraction and white change. The accuracy, sensitivity, and specificity for achalasia were 83.8%, 64.7%, and 100%, respectively."Pinstripe pattern" could be a reliable indicator for early discrimination of primary esophageal achalasia.

  6. Test-Retest Reliability of Diffusion Tensor Imaging in Huntington's Disease.

    Science.gov (United States)

    Cole, James H; Farmer, Ruth E; Rees, Elin M; Johnson, Hans J; Frost, Chris; Scahill, Rachael I; Hobbs, Nicola Z

    2014-03-21

    Diffusion tensor imaging (DTI) has shown microstructural abnormalities in patients with Huntington's Disease (HD) and work is underway to characterise how these abnormalities change with disease progression. Using methods that will be applied in longitudinal research, we sought to establish the reliability of DTI in early HD patients and controls. Test-retest reliability, quantified using the intraclass correlation coefficient (ICC), was assessed using region-of-interest (ROI)-based white matter atlas and voxelwise approaches on repeat scan data from 22 participants (10 early HD, 12 controls). T1 data was used to generate further ROIs for analysis in a reduced sample of 18 participants. The results suggest that fractional anisotropy (FA) and other diffusivity metrics are generally highly reliable, with ICCs indicating considerably lower within-subject compared to between-subject variability in both HD patients and controls. Where ICC was low, particularly for the diffusivity measures in the caudate and putamen, this was partly influenced by outliers. The analysis suggests that the specific DTI methods used here are appropriate for cross-sectional research in HD, and give confidence that they can also be applied longitudinally, although this requires further investigation. An important caveat for DTI studies is that test-retest reliability may not be evenly distributed throughout the brain whereby highly anisotropic white matter regions tended to show lower relative within-subject variability than other white or grey matter regions.

  7. Crisis Reliability Indicators Supporting Emergency Services (CRISES): A Framework for Developing Performance Measures for Behavioral Health Crisis and Psychiatric Emergency Programs.

    Science.gov (United States)

    Balfour, Margaret E; Tanner, Kathleen; Jurica, Paul J; Rhoads, Richard; Carson, Chris A

    2016-01-01

    Crisis and emergency psychiatric services are an integral part of the healthcare system, yet there are no standardized measures for programs providing these services. We developed the Crisis Reliability Indicators Supporting Emergency Services (CRISES) framework to create measures that inform internal performance improvement initiatives and allow comparison across programs. The framework consists of two components-the CRISES domains (timely, safe, accessible, least-restrictive, effective, consumer/family centered, and partnership) and the measures supporting each domain. The CRISES framework provides a foundation for development of standardized measures for the crisis field. This will become increasingly important as pay-for-performance initiatives expand with healthcare reform.

  8. The Interrelation among Faithful Representation (Reliability), Corruption and IFRS Adoption: An Empirical Investigation

    OpenAIRE

    Alexios Kythreotis

    2015-01-01

    Purpose – The degree of corruption, among other things, indicates the non -implementation of laws, weak enforcement of legal sanctions and the existence of non-transparent economic transactions. Therefore, the expected change in reliability (faithful-representation) resulting from the adoption of IAS/IFRS, does not depend solely on the adoption of IAS/IFRS but is also influenced by the degree of corruption in each country. The purpose of this paper is to examine w...

  9. The MOBID-2 pain scale: reliability and responsiveness to pain in patients with dementia.

    Science.gov (United States)

    Husebo, B S; Ostelo, R; Strand, L I

    2014-11-01

    Mobilization-Observation-Behavior-Intensity-Dementia-2 (MOBID-2) pain scale is a staff-administered pain tool for patients with dementia. This study explores MOBID-2's test-retest reliability, measurement error and responsiveness to change. Analyses are based upon data from a cluster randomized trial including 352 patients with advanced dementia from 18 Norwegian nursing homes. Test-retest reliability between baseline and week 2 (n = 163), and weeks 2 and 4 (n = 159) was examined in patients not expected to change (controls), using intraclass correlation coefficient (ICC2.1 ), standard error of measurement (SEM) and smallest detectable change (SDC). Responsiveness was examined by testing six priori-formulated hypotheses about the association between change scores on MOBID-2 and other outcome measures. ICCs of the total MOBID-2 scores were 0.81 (0-2 weeks) and 0.85 (2-4 weeks). SEM and SDC were 1.9 and 3.1 (0-2 weeks) and 1.4 and 2.3 (2-4 weeks), respectively. Five out of six hypotheses were confirmed: MOBID-2 discriminated (p Mini-Mental State Examination, Functional Assessment Staging and Activity of Daily Living. Expected associations between change scores of MOBID-2 and Neuropsychiatric Inventory - Nursing Home version were not confirmed. The SEM and SDC in connection with the MOBID-2 pain scale indicate that the instrument is responsive to a decrease in pain after a SPTP. Satisfactory test-retest reliability across test periods was demonstrated. Change scores ≥ 3 on total and subscales are clinically relevant and are beyond measurement error. © 2014 The Authors. European Journal of Pain published by John Wiley & Sons Ltd on behalf of European Pain Federation - EFIC®.

  10. The Outcome and Assessment Information Set (OASIS): A Review of Validity and Reliability

    Science.gov (United States)

    O’CONNOR, MELISSA; DAVITT, JOAN K.

    2015-01-01

    The Outcome and Assessment Information Set (OASIS) is the patient-specific, standardized assessment used in Medicare home health care to plan care, determine reimbursement, and measure quality. Since its inception in 1999, there has been debate over the reliability and validity of the OASIS as a research tool and outcome measure. A systematic literature review of English-language articles identified 12 studies published in the last 10 years examining the validity and reliability of the OASIS. Empirical findings indicate the validity and reliability of the OASIS range from low to moderate but vary depending on the item studied. Limitations in the existing research include: nonrepresentative samples; inconsistencies in methods used, items tested, measurement, and statistical procedures; and the changes to the OASIS itself over time. The inconsistencies suggest that these results are tentative at best; additional research is needed to confirm the value of the OASIS for measuring patient outcomes, research, and quality improvement. PMID:23216513

  11. Open access to Water Indicators for Climate Change Adaptation: proof-of-concept for the Copernicus Climate Change Service (C3S)

    Science.gov (United States)

    Lottle, Lorna; Arheimer, Berit; Gyllensvärd, Frida; Dejong, Fokke; Ludwig, Fulco; Hutjes, Ronald; Martinez, Bernat

    2017-04-01

    Copernicus Climate Change Service (C3S) is still in the development phase and will combine observations of the climate system with the latest science to develop authoritative, quality-assured information about the past, current and future states of the climate and climate dependent sectors in Europe and worldwide. C3S will provide key indicators on climate change drivers and selected sectorial impacts. The aim of these indicators will be to support adaptation and mitigation. This presentation will show one service already operational as a proof-of-concept of this future climate service. The project "Service for Water Indicators in Climate Change Adaptation" (SWICCA) has developed a sectorial information service for water management. It offers readily available climate-impact data, for open access from the web-site http://swicca.climate.copernicus.eu/. The development is user-driven with the overall goal to speed up the workflow in climate-change adaptation of water management across Europe. The service is co-designed by consultant engineers and agencies in 15 case-studies spread out over the continent. SWICCA has an interactive user-interface, which shows maps and graphs, and facilitates data download in user-friendly formats. In total, more than 900 open dataset are given for various hydrometeorological (and a few socioeconomical) variables, model ensembles, resolutions, time-periods and RCPs. The service offers more than 40 precomputed climate impact indicators (CIIs) and transient time-series of 4 essential climate variables ECVs) with high spatial and temporal resolution. To facilitate both near future and far future assessments, SWICCA provides the indicators for different time ranges; normally, absolute values are given for a reference period (e.g. 1971-2000) and the expected future changes for different 30-year periods, such as early century (2011-2040), mid-century (2041-2070) and end-century (2071-2100). An ensemble of model results is always given to

  12. Reliability engineering: Old problems and new challenges

    International Nuclear Information System (INIS)

    Zio, E.

    2009-01-01

    The first recorded usage of the word reliability dates back to the 1800s, albeit referred to a person and not a technical system. Since then, the concept of reliability has become a pervasive attribute worth of both qualitative and quantitative connotations. In particular, the revolutionary social, cultural and technological changes that have occurred from the 1800s to the 2000s have contributed to the need for a rational framework and quantitative treatment of the reliability of engineered systems and plants. This has led to the rise of reliability engineering as a scientific discipline. In this paper, some considerations are shared with respect to a number of problems and challenges which researchers and practitioners in reliability engineering are facing when analyzing today's complex systems. The focus will be on the contribution of reliability to system safety and on its role within system risk analysis

  13. Prediction of software operational reliability using testing environment factors

    International Nuclear Information System (INIS)

    Jung, Hoan Sung; Seong, Poong Hyun

    1995-01-01

    For many years, many researches have focused on the quantification of software reliability and there are many models developed to quantify software reliability. Most software reliability models estimate the reliability with the failure data collected during the test assuming that the test environments well represent the operation profile. The experiences show that the operational reliability is higher than the test reliability User's interest is on the operational reliability rather than on the test reliability, however. With the assumption that the difference in reliability results from the change of environment, testing environment factors comprising the aging factor and the coverage factor are defined in this study to predict the ultimate operational reliability with the failure data. It is by incorporating test environments applied beyond the operational profile into testing environment factors. The application results are close to the actual data

  14. Changes in health indicators related to health promotion and microcredit programs in the Dominican Republic.

    Science.gov (United States)

    Dohn, Anita L; Chávez, Andrea; Dohn, Michael N; Saturria, Luis; Pimentel, Carlos

    2004-03-01

    To assess the impact of health promotion programs and microcredit programs on three communities in the Dominican Republic. One community had only the health promotion program, one community had only the microcredit program, and one community had both a health promotion program and a microcredit program. This pilot project examined the hypothesis that the largest changes in 11 health indicators that were studied would be in the community with both a health promotion program and a microcredit program, that there would be intermediate changes in the community with only a health promotion program, and that the smallest changes would be in the community with only a microcredit program. The health promotion programs used community volunteers to address two major concerns: (1) the prevalent causes of mortality among children under 5 years of age and (2) women's health (specifically breast and cervical cancer screening). The microcredit program made small loans to individuals to start or expand small businesses. Outcome measures were based on comparisons for 11 health indicators from baseline community surveys (27 households surveyed in each of the three communities, done in December 2000 and January 2001) and from follow-up surveys (also 27 households surveyed in each of the three communities, in June and July 2002, after the health promotion program had been operating for about 13 months). Households were randomly chosen during both the baseline and follow-up surveys, without regard to their involvement in the microcredit or health promotion programs. The health indicators improved in all three communities. However, the degree of change was different among the communities (P microcredit and health promotion programs had the largest changes for 10 of the 11 health indicators. Multisector development is known to be important on a macroeconomic scale. The results of this pilot project support the view that multisector development is also important on a microeconomic level

  15. The reliability of running economy expressed as oxygen cost and energy cost in trained distance runners.

    Science.gov (United States)

    Shaw, Andrew J; Ingham, Stephen A; Fudge, Barry W; Folland, Jonathan P

    2013-12-01

    This study assessed the between-test reliability of oxygen cost (OC) and energy cost (EC) in distance runners, and contrasted it with the smallest worthwhile change (SWC) of these measures. OC and EC displayed similar levels of within-subject variation (typical error < 3.85%). However, the typical error (2.75% vs 2.74%) was greater than the SWC (1.38% vs 1.71%) for both OC and EC, respectively, indicating insufficient sensitivity to confidently detect small, but meaningful, changes in OC and EC.

  16. Climate Change Indicators: Health and Society

    Science.gov (United States)

    ... chapter looks at some of the ways that climate change is affecting human health and society, including changes in Lyme disease, West ... health effects. Why does it matter? Changes in climate affect the ... to human health and welfare. Warmer average temperatures will likely lead ...

  17. New endoscopic indicator of esophageal achalasia: "pinstripe pattern".

    Science.gov (United States)

    Minami, Hitomi; Isomoto, Hajime; Miuma, Satoshi; Kobayashi, Yasutoshi; Yamaguchi, Naoyuki; Urabe, Shigetoshi; Matsushima, Kayoko; Akazawa, Yuko; Ohnita, Ken; Takeshima, Fuminao; Inoue, Haruhiro; Nakao, Kazuhiko

    2015-01-01

    Endoscopic diagnosis of esophageal achalasia lacking typical endoscopic features can be extremely difficult. The aim of this study was to identify simple and reliable early indicator of esophageal achalasia. This single-center retrospective study included 56 cases of esophageal achalasia without previous treatment. As a control, 60 non-achalasia subjects including reflux esophagitis and superficial esophageal cancer were also included in this study. Endoscopic findings were evaluated according to Descriptive Rules for Achalasia of the Esophagus as follows: (1) esophageal dilatation, (2) abnormal retention of liquid and/or food, (3) whitish change of the mucosal surface, (4) functional stenosis of the esophago-gastric junction, and (5) abnormal contraction. Additionally, the presence of the longitudinal superficial wrinkles of esophageal mucosa, "pinstripe pattern (PSP)" was evaluated endoscopically. Then, inter-observer diagnostic agreement was assessed for each finding. The prevalence rates of the above-mentioned findings (1-5) were 41.1%, 41.1%, 16.1%, 94.6%, and 43.9%, respectively. PSP was observed in 60.7% of achalasia, while none of the control showed positivity for PSP. PSP was observed in 26 (62.5%) of 35 cases with shorter history achalasia were 83.8%, 64.7%, and 100%, respectively. "Pinstripe pattern" could be a reliable indicator for early discrimination of primary esophageal achalasia.

  18. The reliability and stability of visual working memory capacity.

    Science.gov (United States)

    Xu, Z; Adam, K C S; Fang, X; Vogel, E K

    2018-04-01

    Because of the central role of working memory capacity in cognition, many studies have used short measures of working memory capacity to examine its relationship to other domains. Here, we measured the reliability and stability of visual working memory capacity, measured using a single-probe change detection task. In Experiment 1, the participants (N = 135) completed a large number of trials of a change detection task (540 in total, 180 each of set sizes 4, 6, and 8). With large numbers of both trials and participants, reliability estimates were high (α > .9). We then used an iterative down-sampling procedure to create a look-up table for expected reliability in experiments with small sample sizes. In Experiment 2, the participants (N = 79) completed 31 sessions of single-probe change detection. The first 30 sessions took place over 30 consecutive days, and the last session took place 30 days later. This unprecedented number of sessions allowed us to examine the effects of practice on stability and internal reliability. Even after much practice, individual differences were stable over time (average between-session r = .76).

  19. Indicators of human health in ecosystems: what do we measure?

    International Nuclear Information System (INIS)

    Cole, D.C.; Eyles, J.; Gibson, B.L.

    1998-01-01

    Increasingly, scientists are being called upon to assist in the development of indicators for monitoring ecosystem health. For human health indicators, they may draw on environmental exposure, human morbidity/mortality or well-being and sustainability approaches. To improve the rigour of indicators, we propose six scientific criteria for indicator selection: (1) data availability, suitability and representativeness (of populations), (2) indicator validity (face, construct, predictive and convergent) and reliability; (3) indicator responsiveness to change; (4) indicator desegregation capability (across personal and community characteristics); (5) indicator comparability (across populations and jurisdictions); and (6) indicator representativeness (across important dimensions of concern). We comment on our current capacity to adhere to such criteria with examples of measures of environmental exposure, human health and sustainability. We recognize the considerable work still required on documenting environment-human health relationships and on monitoring potential indicators in similar ways over time. Yet we argue that such work is essential in order for science to inform policy decisions which affect the health of ecosystems and human health. (Copyright (c) 1998 Elsevier Science B.V., Amsterdam. All rights reserved.)

  20. Evaluating climate change mitigation potential of hydrochars: compounding insights from three different indicators

    DEFF Research Database (Denmark)

    Owsianiak, Mikołaj; Brooks, Jennifer; Renz, Michael

    2017-01-01

    beet, fava bean, onion and lucerne) and two different countries (Spain and Germany), and used three different indicators of climate change: global warming potential (GWP), global temperature change potential (GTP), and climate tipping potential (CTP). We found that although climate change benefits (GWP......) from just sequestration and temporary storage of carbon are sufficient to outweigh impacts stemming from hydrochar production and transportation to the field, even greater benefits stem from replacing climate-inefficient biowaste management treatment options, like composting in Spain. By contrast...

  1. Response of vegetation indices to changes in three measures of leaf water stress

    Science.gov (United States)

    Cohen, Warren B.

    1991-01-01

    The responses of vegetation indices to changes in water stress were evaluated in two separate laboratory experiments. In one experiment the normalized difference vegetation index (NDVI), the near-IR to red ratio (near-IR/red), the Infrared Index (II), and the Moisture Stress Index (MSI) were more highly correlated to leaf water potential in lodgepole pine branches than were the Leaf Water Content Index (LWCI), the mid-IR ratio (Mid-IR), or any of the single Thematic Mapper (TM) bands. In the other experiment, these six indices and the TM Tasseled Cap brightness, greenness, and wetness indices responded to changes in leaf relative water content (RWC) differently than they responded to changes in leaf water content (WC) of three plant species, and the responses were dependent on how experimental replicates were pooled. With no pooling, the LWCI was the most highly correlated index to both RWC and WC among replications, followed by the II, MSI, and wetness. Only the LWCI was highly correlated to RWC and WC when replications were pooled within species. With among species pooling the LWCI was the only index highly correlated with RWC, while the II, MSI, Mid-IR, and wetness were most highly correlated with WC.

  2. Update of indicators for climate change mitigation in Greece

    International Nuclear Information System (INIS)

    Dimitroulopoulou, C.; Ziomas, I.

    2011-01-01

    This paper analyses the factors affecting greenhouse gas (GHG) emissions in Greece, (i.e. the drivers of pressures on climate change), using environmental indicators related to energy, demographics and economic growth. The analysis is based on the data of 2008 and considers types of fuel and sectors. The Kaya identity is used to identify the relationship between drivers and pressures, using annual time series data of National GHG emissions, population, energy consumption and gross domestic product. The analysis shows that over the period 2000-2008, GHG emissions show a slight variation, but they are almost stabilised, with a total increase of 1.6%. Despite the economic growth over that period, this stabilisation may be considered as a combination of reductions in the energy intensity of GDP and the carbon intensity of energy, which are affected by improvements in energy efficiency and introduction of 'cleaner' fuels, such as natural gas and renewables in the energy mixture of the country. - Highlights: → We analyse drivers affecting GHG emissions (pressures on climate) in Greece, using indicators. → Indicators relate to energy, demographics and economic growth. → Kaya identity identifies the relationship between drivers and pressures. → GHG emissions are almost stable due to reductions in energy intensity and carbon intensity of energy. → Improvements in energy efficiency and introduction of clean fuels in energy mix reduce emissions.

  3. An accurate and efficient reliability-based design optimization using the second order reliability method and improved stability transformation method

    Science.gov (United States)

    Meng, Zeng; Yang, Dixiong; Zhou, Huanlin; Yu, Bo

    2018-05-01

    The first order reliability method has been extensively adopted for reliability-based design optimization (RBDO), but it shows inaccuracy in calculating the failure probability with highly nonlinear performance functions. Thus, the second order reliability method is required to evaluate the reliability accurately. However, its application for RBDO is quite challenge owing to the expensive computational cost incurred by the repeated reliability evaluation and Hessian calculation of probabilistic constraints. In this article, a new improved stability transformation method is proposed to search the most probable point efficiently, and the Hessian matrix is calculated by the symmetric rank-one update. The computational capability of the proposed method is illustrated and compared to the existing RBDO approaches through three mathematical and two engineering examples. The comparison results indicate that the proposed method is very efficient and accurate, providing an alternative tool for RBDO of engineering structures.

  4. Systems reliability/structural reliability

    International Nuclear Information System (INIS)

    Green, A.E.

    1980-01-01

    The question of reliability technology using quantified techniques is considered for systems and structures. Systems reliability analysis has progressed to a viable and proven methodology whereas this has yet to be fully achieved for large scale structures. Structural loading variants over the half-time of the plant are considered to be more difficult to analyse than for systems, even though a relatively crude model may be a necessary starting point. Various reliability characteristics and environmental conditions are considered which enter this problem. The rare event situation is briefly mentioned together with aspects of proof testing and normal and upset loading conditions. (orig.)

  5. Epiphytes as an Indicator of Climate Change in Hawaii

    Science.gov (United States)

    Kettwich, S. K.

    2013-12-01

    Although climate change threatens many ecosystems, current research in this field suggests tropical vegetation lags in response. Epiphytes, or arboreal vegetation, occupy tight, climate-defined niches compared with co-occurring life forms such as trees, yet there have been few studies of Hawaii's epiphyte communities. Because of Hawaii Island's natural climatic diversity, it is an ideal location to understand how these intrinsically climate sensitive plants interact with the atmosphere and evaluate how they may serve as a near-term indicator of climate change. Here we establish a baseline from which changes in corticolous epiphyte communities can be monitored as a leading indicator of likely forest changes by 1) investigating patterns of epiphyte abundance and species composition across elevation and precipitation gradients on windward Hawaii Island, and 2) using physiological measurements to investigate the relative importance of rain vs. fog in epiphyte-atmosphere interactions. The precipitation gradient keeps elevation constant at 1000m, while varying precipitation between 2,400 and 6,400 mm/year. The elevation gradient keeps rainfall constant at 3000mm/year, and varies elevation between 200 and 1750 m. Forest sites are dominated by Ohia Lehua (Metrosideros polymorpha) across broad geographic and climatological ranges thus allowing examination of epiphytes on this single host. We quantified bryophytes and vascular plants growing on Ohia trunks with standardized diameter and branching characteristics. Overall, epiphyte communities showed much finer scale responses to climate variation when compared with structurally dominant vegetation (which was broadly similar at all sites). The precipitation gradient exhibits a clear increase in abundance of all epiphyte groups and a definable increase in diversity with increasing rainfall. Results across the elevation gradient show a higher abundance of filmy ferns and bryophytes above the lifting condensation level (about

  6. Waste package reliability analysis

    International Nuclear Information System (INIS)

    Pescatore, C.; Sastre, C.

    1983-01-01

    Proof of future performance of a complex system such as a high-level nuclear waste package over a period of hundreds to thousands of years cannot be had in the ordinary sense of the word. The general method of probabilistic reliability analysis could provide an acceptable framework to identify, organize, and convey the information necessary to satisfy the criterion of reasonable assurance of waste package performance according to the regulatory requirements set forth in 10 CFR 60. General principles which may be used to evaluate the qualitative and quantitative reliability of a waste package design are indicated and illustrated with a sample calculation of a repository concept in basalt. 8 references, 1 table

  7. Reliability of sonographic assessment of tendinopathy in tennis elbow.

    Science.gov (United States)

    Poltawski, Leon; Ali, Syed; Jayaram, Vijay; Watson, Tim

    2012-01-01

    To assess the reliability and compute the minimum detectable change using sonographic scales to quantify the extent of pathology and hyperaemia in the common extensor tendon in people with tennis elbow. The lateral elbows of 19 people with tennis elbow were assessed sonographically twice, 1-2 weeks apart. Greyscale and power Doppler images were recorded for subsequent rating of abnormalities. Tendon thickening, hypoechogenicity, fibrillar disruption and calcification were each rated on four-point scales, and scores were summed to provide an overall rating of structural abnormality; hyperaemia was scored on a five point scale. Inter-rater reliability was established using the intraclass correlation coefficient (ICC) to compare scores assigned independently to the same set of images by a radiologist and a physiotherapist with training in musculoskeletal imaging. Test-retest reliability was assessed by comparing scores assigned by the physiotherapist to images recorded at the two sessions. The minimum detectable change (MDC) was calculated from the test-retest reliability data. ICC values for inter-rater reliability ranged from 0.35 (95% CI: 0.05, 0.60) for fibrillar disruption to 0.77 (0.55, 0.88) for overall greyscale score, and 0.89 (0.79, 0.95) for hyperaemia. Test-retest reliability ranged from 0.70 (0.48, 0.84) for tendon thickening to 0.82 (0.66, 0.90) for overall greyscale score and 0.86 (0.73, 0.93) for calcification. The MDC for the greyscale total score was 2.0/12 and for the hyperaemia score was 1.1/5. The sonographic scoring system used in this study may be used reliably to quantify tendon abnormalities and change over time. A relatively inexperienced imager can conduct the assessment and use the rating scales reliably.

  8. Reliability Engineering

    International Nuclear Information System (INIS)

    Lee, Sang Yong

    1992-07-01

    This book is about reliability engineering, which describes definition and importance of reliability, development of reliability engineering, failure rate and failure probability density function about types of it, CFR and index distribution, IFR and normal distribution and Weibull distribution, maintainability and movability, reliability test and reliability assumption in index distribution type, normal distribution type and Weibull distribution type, reliability sampling test, reliability of system, design of reliability and functionality failure analysis by FTA.

  9. Establishment of an indicator concept for the German strategy on adaptation to climate change

    Energy Technology Data Exchange (ETDEWEB)

    Schoenthaler, Konstanze; Andrian-Werburg, Stefan von; Wulfert, Katrin [Bosch und Partner GmbH, Muenchen (Germany); Luthardt, Vera; Kreinsen, Beatrice; Schultz-Sternberg, R.; Hommel, Robert [Hochschule fuer Nachhaltige Entwicklung Eberswalde (Germany)

    2010-11-15

    Even if we succeed in achieving the EU target of reducing global warming to 2 C, it will be absolutely essential to adapt to changing climatic conditions. The greenhouse gases currently present in the atmosphere will influence the climate in coming decades. The day on which it is quite clear which climatic scenario prevails, so that it is possible to model all relevant processes down to regional level, will be the day on which it is too late to adapt to the actual scenario. Our endeavours to adapt to climate change do not mean, however, that we can neglect to take measures in order to reduce the output of greenhouse gases. It is important to remember that on their own, neither adaptation nor mitigation can prevent the grave impacts resulting from climate change. In fact, they complement each other meaningfully thus helping to alleviate the risks of climate change. On 17th December 2008 the German Federal Cabinet adopted the DAS (German Strategy for the Adaptation to Climate Change), (Bundesregierung 2008). The DAS has created the framework for adapting to the consequences of climate change in Germany. First and fore-most, the DAS contributes its guidelines at Federal level, to provide a guideline for agents at other levels. The Strategy lays the foundation for a medium-term process. In conjunction with the individual Federal States and other groups representing various sectors of society, the Strategy provides a step-by-step assessment of the risks of climate change. Furthermore, it states the potential requirements for action, and defines the appropriate goals and potential adaptation measures to be developed and implemented in this process. In due course, the Federal Environment Agency (UBA) will design a comprehensive set of tools to support and advance the DAS. An integral part of this will be the Special Information System 'Adaptation' (FISKA) and an Indicator System to aid adaptation. The latter is one of the key tasks identified for the DAS. As far

  10. Validity and Reliability of 10-Hz Global Positioning System to Assess In-line Movement and Change of Direction

    Directory of Open Access Journals (Sweden)

    Pantelis T. Nikolaidis

    2018-03-01

    Full Text Available The objectives of the present study were to examine the validity and reliability of the 10 Hz Johan GPS unit in assessing in-line movement and change of direction. The validity was tested against the criterion measure of 200 m track-and-field (track-and-field athletes, n = 8 and 20 m shuttle run endurance test (female soccer players, n = 20. Intra-unit and inter-unit reliability was tested by intra-class correlation coefficient (ICC and coefficient of variation (CV, respectively. An analysis of variance examined differences between the GPS measurement and five laps of 200 m at 15 km/h, and t-test examined differences between the GPS measurement and 20 m shuttle run endurance test. The difference between the GPS measurement and 200 m distance ranged from −0.13 ± 3.94 m (95% CI −3.42; 3.17 in the first lap to 2.13 ± 2.64 m (95% CI −0.08; 4.33 in the fifth lap. A good intra-unit reliability was observed in 200 m (ICC = 0.833, 95% CI 0.535; 0.962. Inter-unit CV ranged from 1.31% (fifth lap to 2.20% (third lap. The difference between the GPS measurement and 20 m shuttle run endurance test ranged from 0.33 ± 4.16 m (95% CI −10.01; 10.68 in 11.5 km/h to 9.00 ± 5.30 m (95% CI 6.44; 11.56 in 8.0 km/h. A moderate intra-unit reliability was shown in the second and third stage of the 20 m shuttle run endurance test (ICC = 0.718, 95% CI 0.222;0.898 and good reliability in the fifth, sixth, seventh and eighth (ICC = 0.831, 95% CI −0.229;0.996. Inter-unit CV ranged from 2.08% (11.5 km/h to 3.92% (8.5 km/h. Based on these findings, it was concluded that the 10 Hz Johan system offers an affordable valid and reliable tool for coaches and fitness trainers to monitor training and performance.

  11. The Interrelation among Faithful Representation (Reliability), Corruption and IFRS Adoption: An Empirical Investigation

    OpenAIRE

    Alexios Kythreotis

    2015-01-01

    Purpose – The degree of corruption, among other things, indicates the non -implementation of laws, weak enforcement of legal sanctions and the existence of non-transparent economic transactions. Therefore, the expected change in reliability (faithful-representation) resulting from the adoption of IAS/IFRS, does not depend solely on the adoption of IAS/IFRS but is also influenced by the degree of corruption in each country. The purpose of this paper is to examine whether the above statement is...

  12. Between Flexibility and Reliability. Changing Planning Culture in China

    Directory of Open Access Journals (Sweden)

    Chiu-Yuan Wang

    2014-10-01

    Full Text Available The aim of this research is to provide an outline to address questions with regard to the transformation of planning in China that has occurred after the 1980s. The research is using “planning evolution” as the main research skeleton. The starting point is to investigate to what extent Chinese urban planning has developed after the opening up and other reforms under the state-led and market-driven modes of Chinese reformation, and to investigate how the different modes and various actors have influenced urban planning, based on the investigation of the respective political and economic changes within the initial reformation in general, and planning in particular. In recent years, China has undeniably undergone a dramatic process of urban growth and transformation. Apart from its speed and scope, it is less recognized that these processes are confronting the Chinese planning institutions with new and unexpected demands almost on a daily basis. In reference to the increasing importance of private investments and developments within the Chinese urbanization process, a new balance between public planning and private developments, and between top-down and bottom-up approaches is required to be able to generate both a reliable and responsible framework for long-term urban development and a flexible system of implementation that meets the needs of changing conditions and new demands. Flexibility and reliability become the new demands for planning practice. Based on the theory of planning culture, planning traditions, concepts, systems and decision-making processes are always related to the cultural context and cultural background of the people and societies involved. Investigating the contemporary urban transformation and urban development processes in China can allow us to outline the new planning culture of contemporary China in relation to its historical roots and traditional characteristics in a long term framework. I argue that the changing

  13. Reliability

    OpenAIRE

    Condon, David; Revelle, William

    2017-01-01

    Separating the signal in a test from the irrelevant noise is a challenge for all measurement. Low test reliability limits test validity, attenuates important relationships, and can lead to regression artifacts. Multiple approaches to the assessment and improvement of reliability are discussed. The advantages and disadvantages of several different approaches to reliability are considered. Practical advice on how to assess reliability using open source software is provided.

  14. Interrater Reliability of the Categorization of Late Radiographic Changes After Lung Stereotactic Body Radiation Therapy

    Energy Technology Data Exchange (ETDEWEB)

    Faruqi, Salman [Department of Radiation Oncology, Princess Margaret Cancer Centre, Toronto, ON (Canada); Giuliani, Meredith E., E-mail: meredith.giuliani@rmp.uhn.on.ca [Department of Radiation Oncology, Princess Margaret Cancer Centre, Toronto, ON (Canada); Raziee, Hamid; Yap, Mei Ling [Department of Radiation Oncology, Princess Margaret Cancer Centre, Toronto, ON (Canada); Roberts, Heidi [Department of Radiology, University Health Network, Toronto, Ontario (Canada); Le, Lisa W. [Department of Biostatistics, Princess Margaret Cancer Centre, Toronto, Ontario (Canada); Brade, Anthony; Cho, John; Sun, Alexander; Bezjak, Andrea; Hope, Andrew J. [Department of Radiation Oncology, Princess Margaret Cancer Centre, Toronto, ON (Canada)

    2014-08-01

    Purpose: Radiographic changes after lung stereotactic body radiation therapy (SBRT) have been categorized into 4 groups: modified conventional pattern (A), mass-like fibrosis; (B), scar-like fibrosis (C), and no evidence of increased density (D). The purpose of this study was to assess the interrater reliability of this categorization system in patients with early-stage non-small cell lung cancer (NSCLC). Methods and Materials: Seventy-seven patients were included in this study, all treated with SBRT for early-stage (T1/2) NSCLC at a single institution, with a minimum follow-up of 6 months. Six experienced clinicians familiar with post-SBRT radiographic changes scored the serial posttreatment CT images independently in a blinded fashion. The proportion of patients categorized as A, B, C, or D at each interval was determined. Krippendorff's alpha (KA), Multirater kappa (M-kappa), and Gwet's AC1 (AC1) scores were used to establish interrater reliability. A leave-one-out analysis was performed to demonstrate the variability among raters. Interrater agreement of the first and last 20 patients scored was calculated to explore whether a training effect existed. Results: The number of ratings ranged from 450 at 6 months to 84 at 48 months of follow-up. The proportion of patients in each category was as follows: A, 45%; B, 16%; C, 13%; and D, 26%. KA and M-kappa ranged from 0.17 to 0.34. AC1 measure range was 0.22 to 0.48. KA increased from 0.24 to 0.36 at 12 months with training. The percent agreement for pattern A peaked at 12 month with a 54% chance of having >50% raters in agreement and decreased over time, whereas that for patterns B and C increased over time to a maximum of 20% and 22%, respectively. Conclusion: This post-SBRT radiographic change categorization system has modest interrater agreement, and there is a suggestion of a training effect. Patterns of fibrosis evolve after SBRT and alternative categorization systems should be evaluated.

  15. Precision of lumbar intervertebral measurements: does a computer-assisted technique improve reliability?

    Science.gov (United States)

    Pearson, Adam M; Spratt, Kevin F; Genuario, James; McGough, William; Kosman, Katherine; Lurie, Jon; Sengupta, Dilip K

    2011-04-01

    Comparison of intra- and interobserver reliability of digitized manual and computer-assisted intervertebral motion measurements and classification of "instability." To determine if computer-assisted measurement of lumbar intervertebral motion on flexion-extension radiographs improves reliability compared with digitized manual measurements. Many studies have questioned the reliability of manual intervertebral measurements, although few have compared the reliability of computer-assisted and manual measurements on lumbar flexion-extension radiographs. Intervertebral rotation, anterior-posterior (AP) translation, and change in anterior and posterior disc height were measured with a digitized manual technique by three physicians and by three other observers using computer-assisted quantitative motion analysis (QMA) software. Each observer measured 30 sets of digital flexion-extension radiographs (L1-S1) twice. Shrout-Fleiss intraclass correlation coefficients for intra- and interobserver reliabilities were computed. The stability of each level was also classified (instability defined as >4 mm AP translation or 10° rotation), and the intra- and interobserver reliabilities of the two methods were compared using adjusted percent agreement (APA). Intraobserver reliability intraclass correlation coefficients were substantially higher for the QMA technique THAN the digitized manual technique across all measurements: rotation 0.997 versus 0.870, AP translation 0.959 versus 0.557, change in anterior disc height 0.962 versus 0.770, and change in posterior disc height 0.951 versus 0.283. The same pattern was observed for interobserver reliability (rotation 0.962 vs. 0.693, AP translation 0.862 vs. 0.151, change in anterior disc height 0.862 vs. 0.373, and change in posterior disc height 0.730 vs. 0.300). The QMA technique was also more reliable for the classification of "instability." Intraobserver APAs ranged from 87 to 97% for QMA versus 60% to 73% for digitized manual

  16. A Study on the Land-Cover Change Indicators of Taipei Metropolitan Areas

    International Nuclear Information System (INIS)

    Huang, Kuo-Ching; Chan, Shih-Laing

    2014-01-01

    The traditional research of land cover/land use change sets focus on the spatial unit of parcel or grid for analysis and simulation. Since the change of individual land use would be affected by the surrounding land uses, there is another possibility to explore the land use change in terms of spatial pattern. The paper applies indicators of landscape metrics to analyze pattern characteristics of urban structure, and cluster analysis and discriminant analysis to identify the type of spatial pattern. This paper attempts to analyze land use pattern and its changes by metric analysis with patch-corridor-matrix structure. The process includes three phases. The first phase is to explore categories of land use pattern and attributes by cluster analysis. The second phase is to analyze pattern changes with different periods and to identify properties of pattern changes in the whole system. The final phase is to classify the pattern changes and to look for the relation between different patterns. Through analysis of pattern changes, it would be helpful to realize urban development relative to landscape metrics and to offer new thinking other than traditional urban development thinking

  17. Experimental research of fuel element reliability

    International Nuclear Information System (INIS)

    Cech, B.; Novak, J.; Chamrad, B.

    1980-01-01

    The rate and extent of the damage of the can integrity for fission products is the basic criterion of reliability. The extent of damage is measurable by the fission product leakage into the reactor coolant circuit. An analysis is made of the causes of the fuel element can damage and a model is proposed for testing fuel element reliability. Special experiments should be carried out to assess partial processes, such as heat transfer and fuel element surface temperature, fission gas liberation and pressure changes inside the element, corrosion weakening of the can wall, can deformation as a result of mechanical interactions. The irradiation probe for reliability testing of fuel elements is described. (M.S.)

  18. 2002 reliability report on the French power system; Bilan 2002 de la surete du systeme electrique francais

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2003-07-01

    Ensuring the reliability of the power system is one of the main responsibilities entrusted to RTE, the French transmission system operator, by the Act of February 10, 2000. Reliability must be maintained, both now and in the future. This means that RTE is required to: ensure the normal operation of the power system, limit the number of incidents and avoid major incidents, limit the consequences of major incidents when they do occur. By publishing a yearly reliability report on the French power system, RTE is clearly showing its ambition to encourage long-term supervision of all aspects of system reliability development. By this approach, RTE's intention is to help develop a reliability culture, by all the actors concerned (both RTE and network users) more aware of their role in establishing reliability, and by promoting reliability issues and comparisons with international transmission system operator associations (UCTE , ETSO ). The annual reliability report is drawn up around the following themes: a broad overview of changes in the internal and external environment that have implications for reliability, developments in the various elements that make up the reliability referential during the course of the year, developments on measures aimed at promoting reliability, in terms of equipment, organisation and human resources, lessons learned from events that took place over the year, the presentation of reliability-related indicators, RTE's control loop, and the developments under way at present.

  19. Pattern description and reliability parameters of six force-time related indices measured with plantar pressure measurements.

    Science.gov (United States)

    Deschamps, Kevin; Roosen, Philip; Bruyninckx, Herman; Desloovere, Kaat; Deleu, Paul-Andre; Matricali, Giovanni A; Peeraer, Louis; Staes, Filip

    2013-09-01

    Functional interpretation of plantar pressure measurements is commonly done through the use of ratios and indices which are preceded by the strategic combination of a subsampling method and selection of physical quantities. However, errors which may arise throughout the determination of these temporal indices/ratio calculations (T-IRC) have not been quantified. The purpose of the current study was therefore to estimate the reliability of T-IRC following semi-automatic total mapping (SATM). Using a repeated-measures design, two experienced therapists performed three subsampling sessions on three left and right pedobarographic footprints of ten healthy participants. Following the subsampling, six T-IRC were calculated: Rearfoot-Forefoot_fti, Rearfoot-Midfoot_fti, Forefoot medial/lateral_fti, First ray_fti, Metatarsal 1-Metatarsal 5_fti, Foot medial-lateral_fti. Patterns of the T-IRC were found to be consistent and in good agreement with corresponding knowledge from the literature. The inter-session errors of both therapists were similar in pattern and magnitude. The lowest peak inter-therapist error was found in the First ray_fti (6.5 a.u.) whereas the highest peak inter-therapist error was observed in the Forefoot medial/lateral_fti (27.0 a.u.) The magnitude of the inter-session and inter-therapist error varied over time, precluding the calculation of a simple numerical value for the error. The difference between both error parameters of all T-IRC was negligible which underscores the repeatability of the SATM protocol. The current study reports consistent patterns for six T-IRC and similar inter-session and inter-therapist error. The proposed SATM protocol and the T-IRC may therefore serve as basis for functional interpretation of footprint data. Copyright © 2013 Elsevier B.V. All rights reserved.

  20. A reliability analysis tool for SpaceWire network

    Science.gov (United States)

    Zhou, Qiang; Zhu, Longjiang; Fei, Haidong; Wang, Xingyou

    2017-04-01

    A SpaceWire is a standard for on-board satellite networks as the basis for future data-handling architectures. It is becoming more and more popular in space applications due to its technical advantages, including reliability, low power and fault protection, etc. High reliability is the vital issue for spacecraft. Therefore, it is very important to analyze and improve the reliability performance of the SpaceWire network. This paper deals with the problem of reliability modeling and analysis with SpaceWire network. According to the function division of distributed network, a reliability analysis method based on a task is proposed, the reliability analysis of every task can lead to the system reliability matrix, the reliability result of the network system can be deduced by integrating these entire reliability indexes in the matrix. With the method, we develop a reliability analysis tool for SpaceWire Network based on VC, where the computation schemes for reliability matrix and the multi-path-task reliability are also implemented. By using this tool, we analyze several cases on typical architectures. And the analytic results indicate that redundancy architecture has better reliability performance than basic one. In practical, the dual redundancy scheme has been adopted for some key unit, to improve the reliability index of the system or task. Finally, this reliability analysis tool will has a directive influence on both task division and topology selection in the phase of SpaceWire network system design.

  1. On the NPP structural reliability

    International Nuclear Information System (INIS)

    Klemin, A.I.; Polyakov, E.F.

    1980-01-01

    Reviewed are the main statements peculiarities and possibilities of the first branch guiding technical material (GTM) ''The methods of calculation of structural reliability of NPP and its systems at the stage of projecting''. It is stated, that in GTM presented are recomendations on the calculation of reliability of such specific systems, as the system of the reactor control and protection the system of measuring instruments and automatics and safe systems. GTM are based on analytical methods of modern theory of realibility with the Use of metodology of minimal cross sections of complex systems. It is stressed, that the calculations on the proposed methods permit to calculate a wide complex of reliability parameters, reflecting separately or together prorerties of NPP dependability and maintainability. For NPP, operating by a variable schedule of leading, aditionally considered are parameters, characterizing reliability with account of the proposed regime of power change, i.e. taking into account failures, caused by decrease of the obtained power lower, than the reguired or increase of the required power higher, than the obtained

  2. Reliability in perceptual analysis of voice quality.

    Science.gov (United States)

    Bele, Irene Velsvik

    2005-12-01

    This study focuses on speaking voice quality in male teachers (n = 35) and male actors (n = 36), who represent untrained and trained voice users, because we wanted to investigate normal and supranormal voices. In this study, both substantial and methodologic aspects were considered. It includes a method for perceptual voice evaluation, and a basic issue was rater reliability. A listening group of 10 listeners, 7 experienced speech-language therapists, and 3 speech-language therapist students evaluated the voices by 15 vocal characteristics using VA scales. Two sets of voice signals were investigated: text reading (2 loudness levels) and sustained vowel (3 levels). The results indicated a high interrater reliability for most perceptual characteristics. Connected speech was evaluated more reliably, especially at the normal level, but both types of voice signals were evaluated reliably, although the reliability for connected speech was somewhat higher than for vowels. Experienced listeners tended to be more consistent in their ratings than did the student raters. Some vocal characteristics achieved acceptable reliability even with a smaller panel of listeners. The perceptual characteristics grouped in 4 factors reflected perceptual dimensions.

  3. Validity and reliability of new agility test among elite and subelite under 14-soccer players.

    Directory of Open Access Journals (Sweden)

    Younés Hachana

    Full Text Available BACKGROUND: Agility is a determinant component in soccer performance. This study aimed to evaluate the reliability and sensitivity of a "Modified Illinois change of direction test" (MICODT in ninety-five U-14 soccer players. METHODS: A total of 95 U-14 soccer players (mean ± SD: age: 13.61 ± 1.04 years; body mass: 30.52 ± 4.54 kg; height: 1.57 ± 0.1 m from a professional and semi-professional soccer academy, participated to this study. Sixty of them took part in reliability analysis and thirty-two in sensitivity analysis. RESULTS: The intraclass correlation coefficient (ICC that aims to assess relative reliability of the MICODT was of 0.99, and its standard error of measurement (SEM for absolute reliability was <5% (1.24%. The MICODT's capacity to detect change is "good", it's SEM (0.10 s was ≤ SWC (0.33 s. The MICODT is significantly correlated to the Illinois change of direction speed test (ICODT (r = 0.77; p<0.0001. The ICODT's MDC95 (0.64 s was twice about the MICODT's MDC95 (0.28 s, indicating that MICODT presents better ability to detect true changes than ICODT. The MICODT provided good sensitivity since elite U-14 soccer players were better than non-elite one on MICODT (p = 0.005; dz = 1.01 [large]. This was supported by an area under the ROC curve of 0.77 (CI 95%, 0.59 to 0.89, p<0.0008. The difference observed in these two groups in ICODT was not statistically significant (p = 0.14; dz = 0.51 [small], showing poor discriminant ability. CONCLUSION: MICODT can be considered as more suitable protocol for assessing agility performance level than ICODT in U-14 soccer players.

  4. The development of a reliable amateur boxing performance analysis template.

    Science.gov (United States)

    Thomson, Edward; Lamb, Kevin; Nicholas, Ceri

    2013-01-01

    The aim of this study was to devise a valid performance analysis system for the assessment of the movement characteristics associated with competitive amateur boxing and assess its reliability using analysts of varying experience of the sport and performance analysis. Key performance indicators to characterise the demands of an amateur contest (offensive, defensive and feinting) were developed and notated using a computerised notational analysis system. Data were subjected to intra- and inter-observer reliability assessment using median sign tests and calculating the proportion of agreement within predetermined limits of error. For all performance indicators, intra-observer reliability revealed non-significant differences between observations (P > 0.05) and high agreement was established (80-100%) regardless of whether exact or the reference value of ±1 was applied. Inter-observer reliability was less impressive for both analysts (amateur boxer and experienced analyst), with the proportion of agreement ranging from 33-100%. Nonetheless, there was no systematic bias between observations for any indicator (P > 0.05), and the proportion of agreement within the reference range (±1) was 100%. A reliable performance analysis template has been developed for the assessment of amateur boxing performance and is available for use by researchers, coaches and athletes to classify and quantify the movement characteristics of amateur boxing.

  5. CERTS: Consortium for Electric Reliability Technology Solutions - Research Highlights

    Energy Technology Data Exchange (ETDEWEB)

    Eto, Joseph

    2003-07-30

    Historically, the U.S. electric power industry was vertically integrated, and utilities were responsible for system planning, operations, and reliability management. As the nation moves to a competitive market structure, these functions have been disaggregated, and no single entity is responsible for reliability management. As a result, new tools, technologies, systems, and management processes are needed to manage the reliability of the electricity grid. However, a number of simultaneous trends prevent electricity market participants from pursuing development of these reliability tools: utilities are preoccupied with restructuring their businesses, research funding has declined, and the formation of Independent System Operators (ISOs) and Regional Transmission Organizations (RTOs) to operate the grid means that control of transmission assets is separate from ownership of these assets; at the same time, business uncertainty, and changing regulatory policies have created a climate in which needed investment for transmission infrastructure and tools for reliability management has dried up. To address the resulting emerging gaps in reliability R&D, CERTS has undertaken much-needed public interest research on reliability technologies for the electricity grid. CERTS' vision is to: (1) Transform the electricity grid into an intelligent network that can sense and respond automatically to changing flows of power and emerging problems; (2) Enhance reliability management through market mechanisms, including transparency of real-time information on the status of the grid; (3) Empower customers to manage their energy use and reliability needs in response to real-time market price signals; and (4) Seamlessly integrate distributed technologies--including those for generation, storage, controls, and communications--to support the reliability needs of both the grid and individual customers.

  6. Reliability-Based Robustness Analysis for a Croatian Sports Hall

    DEFF Research Database (Denmark)

    Čizmar, Dean; Kirkegaard, Poul Henning; Sørensen, John Dalsgaard

    2011-01-01

    This paper presents a probabilistic approach for structural robustness assessment for a timber structure built a few years ago. The robustness analysis is based on a structural reliability based framework for robustness and a simplified mechanical system modelling of a timber truss system....... A complex timber structure with a large number of failure modes is modelled with only a few dominant failure modes. First, a component based robustness analysis is performed based on the reliability indices of the remaining elements after the removal of selected critical elements. The robustness...... is expressed and evaluated by a robustness index. Next, the robustness is assessed using system reliability indices where the probabilistic failure model is modelled by a series system of parallel systems....

  7. Application of SAW method for multiple-criteria comparative analysis of the reliability of heat supply organizations

    Science.gov (United States)

    Akhmetova, I. G.; Chichirova, N. D.

    2016-12-01

    Heat supply is the most energy-consuming sector of the economy. Approximately 30% of all used primary fuel-and-energy resources is spent on municipal heat-supply needs. One of the key indicators of activity of heat-supply organizations is the reliability of an energy facility. The reliability index of a heat supply organization is of interest to potential investors for assessing risks when investing in projects. The reliability indices established by the federal legislation are actually reduced to a single numerical factor, which depends on the number of heat-supply outages in connection with disturbances in operation of heat networks and the volume of their resource recovery in the calculation year. This factor is rather subjective and may change in a wide range during several years. A technique is proposed for evaluating the reliability of heat-supply organizations with the use of the simple additive weighting (SAW) method. The technique for integrated-index determination satisfies the following conditions: the reliability level of the evaluated heat-supply system is represented maximum fully and objectively; the information used for the reliability-index evaluation is easily available (is located on the Internet in accordance with demands of data-disclosure standards). For reliability estimation of heat-supply organizations, the following indicators were selected: the wear of equipment of thermal energy sources, the wear of heat networks, the number of outages of supply of thermal energy (heat carrier due to technological disturbances on heat networks per 1 km of heat networks), the number of outages of supply of thermal energy (heat carrier due to technologic disturbances on thermal energy sources per 1 Gcal/h of installed power), the share of expenditures in the cost of thermal energy aimed at recovery of the resource (renewal of fixed assets), coefficient of renewal of fixed assets, and a coefficient of fixed asset retirement. A versatile program is developed

  8. Relative and Absolute Reliability of the Professionalism in Physical Therapy Core Values Self-Assessment Tool.

    Science.gov (United States)

    Furgal, Karen E; Norris, Elizabeth S; Young, Sonia N; Wallmann, Harvey W

    2018-01-01

    Development of professional behaviors in Doctor of Physical Therapy (DPT) students is an important part of professional education. The American Physical Therapy Association (APTA) has developed the Professionalism in Physical Therapy Core Values Self-Assessment (PPTCV-SA) tool to increase awareness of personal values in practice. The PPTCV-SA has been used to measure growth in professionalism following a clinical or educational experience. There are few studies reporting psychometric properties of the PPTCV-SA. The purpose of this study was to establish properties of relative reliability (intraclass correlation coefficient, iCC) and absolute reliability (standard error of measurement, SEM; minimal detectable change, MDC) of the PPTCV-SA. in this project, 29 first-year students in a DPT program were administered the PPTCVA-SA on two occasions, 2 weeks apart. Paired t-tests were used to examine stability in PPTCV-SA scores on the two occasions. iCCs were calculated as a measure of relative reliability and for use in the calculation of the absolute reliability measures of SEM and MDC. Results of paired t-tests indicated differences in the subscale scores between times 1 and 2 were non-significant, except for three subscales: Altruism (p=0.01), Excellence (p=0.05), and Social Responsibility (p=0.02). iCCs for test-retest reliability were moderate-to-good for all subscales, with SEMs ranging from 0.30 to 0.62, and MDC95 ranging from 0.83 to 1.71. These results can guide educators and researchers when determining the likelihood of true change in professionalism following a professional development activity.

  9. Reliability of quantitative echocardiography in adult sheep and goats

    Directory of Open Access Journals (Sweden)

    Hallowell Gayle D

    2012-09-01

    Full Text Available Abstract Background Echocardiography is a non-invasive method for assessment of the ovine and caprine heart. Complete reference ranges for cardiac dimensions and time indices for both species are not currently available and reliability of these measurements has not been evaluated. The objectives for this study are to report reliability, normal cardiac dimensions and time indices in a large group of adult sheep and goats. Fifty-one adult sheep and forty adult goats were recruited. Full echocardiographic examinations were performed in the standing unsedated animal. All animals underwent echocardiography four times in a 72-hour period. Echocardiography was performed three times by one author and once by another. Images were stored and measured offline. Technique and measurement repeatability and reproducibility and any differences due to animal or day were evaluated. Reference ranges (mean ± 2 standard deviations were calculated for both species. Results Majority of the images obtained were of good to excellent quality. Image acquisition was straightforward with 5.4% of animals demonstrating a small scanning window. Reliability was excellent for majority of dimensions and time indices. There was less variation in repeatability when compared with reproducibility and differences were greater for technique than for measurements. Dimensions that were less reliable included those for right ventricular diameter and left ventricular free wall. There were many differences in cardiac dimensions between sheep and goats. Conclusions This study has demonstrated that specific reference ranges are required for these two species. Repeatability and reproducibility were excellent for the majority of cardiac dimensions and time indices suggesting that this technique is reliable and valuable for examination of clinical cases over time and for longitudinal research studies.

  10. Reliability of an interactive computer program for advance care planning.

    Science.gov (United States)

    Schubart, Jane R; Levi, Benjamin H; Camacho, Fabian; Whitehead, Megan; Farace, Elana; Green, Michael J

    2012-06-01

    Despite widespread efforts to promote advance directives (ADs), completion rates remain low. Making Your Wishes Known: Planning Your Medical Future (MYWK) is an interactive computer program that guides individuals through the process of advance care planning, explaining health conditions and interventions that commonly involve life or death decisions, helps them articulate their values/goals, and translates users' preferences into a detailed AD document. The purpose of this study was to demonstrate that (in the absence of major life changes) the AD generated by MYWK reliably reflects an individual's values/preferences. English speakers ≥30 years old completed MYWK twice, 4 to 6 weeks apart. Reliability indices were assessed for three AD components: General Wishes; Specific Wishes for treatment; and Quality-of-Life values (QoL). Twenty-four participants completed the study. Both the Specific Wishes and QoL scales had high internal consistency in both time periods (Knuder Richardson formula 20 [KR-20]=0.83-0.95, and 0.86-0.89). Test-retest reliability was perfect for General Wishes (κ=1), high for QoL (Pearson's correlation coefficient=0.83), but lower for Specific Wishes (Pearson's correlation coefficient=0.57). MYWK generates an AD where General Wishes and QoL (but not Specific Wishes) statements remain consistent over time.

  11. Reliability of an Interactive Computer Program for Advance Care Planning

    Science.gov (United States)

    Levi, Benjamin H.; Camacho, Fabian; Whitehead, Megan; Farace, Elana; Green, Michael J

    2012-01-01

    Abstract Despite widespread efforts to promote advance directives (ADs), completion rates remain low. Making Your Wishes Known: Planning Your Medical Future (MYWK) is an interactive computer program that guides individuals through the process of advance care planning, explaining health conditions and interventions that commonly involve life or death decisions, helps them articulate their values/goals, and translates users' preferences into a detailed AD document. The purpose of this study was to demonstrate that (in the absence of major life changes) the AD generated by MYWK reliably reflects an individual's values/preferences. English speakers ≥30 years old completed MYWK twice, 4 to 6 weeks apart. Reliability indices were assessed for three AD components: General Wishes; Specific Wishes for treatment; and Quality-of-Life values (QoL). Twenty-four participants completed the study. Both the Specific Wishes and QoL scales had high internal consistency in both time periods (Knuder Richardson formula 20 [KR-20]=0.83–0.95, and 0.86–0.89). Test-retest reliability was perfect for General Wishes (κ=1), high for QoL (Pearson's correlation coefficient=0.83), but lower for Specific Wishes (Pearson's correlation coefficient=0.57). MYWK generates an AD where General Wishes and QoL (but not Specific Wishes) statements remain consistent over time. PMID:22512830

  12. The Interrelation among Faithful Representation (Reliability, Corruption and IFRS Adoption: An Empirical Investigation

    Directory of Open Access Journals (Sweden)

    Alexios Kythreotis

    2015-08-01

    Full Text Available Purpose – The degree of corruption, among other things, indicates the non -implementation of laws, weak enforcement of legal sanctions and the existence of non-transparent economic transactions. Therefore, the expected change in reliability (faithful-representation resulting from the adoption of IAS/IFRS, does not depend solely on the adoption of IAS/IFRS but is also influenced by the degree of corruption in each country. The purpose of this paper is to examine whether the above statement is true. Design/methodology/approach – The data were taken from DataStream database and the sample period consists of listed companies of fifteen European countries that adopted IAS/IFRS mandatorily. The time horizon is 10 years, from 2000 until 2009. The period between 2000 and 2004 is defined as the period before the adoption, while the period between 2005 and 2009 is defined as the period after the adoption. The reliability/faithful representation of financial statements - as defined by the Conceptual Framework - is detected through regression analysis. Findings – The findings advocate that the adoption of IFRS/IAS seems to be not enough. It appears that the level of reliability of financial statements in every country does not depend solely on the adoption of IAS/IFRS but is also influenced by the degree of corruption in each country. Research limitations/implications – The models that are used for the measurement of reliability have as an independent variable the short-term accruals. Given that, the models fail to take into consideration accounting treatments that concern non-current assets/liabilities. Originality/value – The findings that are identified for counties with a high degree of corruption indicate a statistically significant reduction in reliability after the adoption of IAS/IFRS. These findings constitute a useful tool for the IASB and the European Commission as well as for the users of financial statements.

  13. Sterols indicate water quality and wastewater treatment efficiency.

    Science.gov (United States)

    Reichwaldt, Elke S; Ho, Wei Y; Zhou, Wenxu; Ghadouani, Anas

    2017-01-01

    As the world's population continues to grow, water pollution is presenting one of the biggest challenges worldwide. More wastewater is being generated and the demand for clean water is increasing. To ensure the safety and health of humans and the environment, highly efficient wastewater treatment systems, and a reliable assessment of water quality and pollutants are required. The advance of holistic approaches to water quality management and the increasing use of ecological water treatment technologies, such as constructed wetlands and waste stabilisation ponds (WSPs), challenge the appropriateness of commonly used water quality indicators. Instead, additional indicators, which are direct measures of the processes involved in the stabilisation of human waste, have to be established to provide an in-depth understanding of system performance. In this study we identified the sterol composition of wastewater treated in WSPs and assessed the suitability of human sterol levels as a bioindicator of treatment efficiency of wastewater in WSPs. As treatment progressed in WSPs, the relative abundance of human faecal sterols, such as coprostanol, epicoprostanol, 24-ethylcoprostanol, and sitostanol decreased significantly and the sterol composition in wastewater changed significantly. Furthermore, sterol levels were found to be correlated with commonly used wastewater quality indicators, such as BOD, TSS and E. coli. Three of the seven sterol ratios that have previously been used to track sewage pollution in the environment, detected a faecal signal in the effluent of WSPs, however, the others were influenced by high prevalence of sterols originating from algal and fungal activities. This finding poses a concern for environmental assessment studies, because environmental pollution from waste stabilisation ponds can go unnoticed. In conclusion, faecal sterols and their ratios can be used as reliable indicators of treatment efficiency and water quality during wastewater

  14. Reliability of contractile properties of the knee extensor muscles in individuals with post-polio syndrome.

    Directory of Open Access Journals (Sweden)

    Eric L Voorn

    Full Text Available To assess the reliability of contractile properties of the knee extensor muscles in 23 individuals with post-polio syndrome (PPS and 18 age-matched healthy individuals.Contractile properties of the knee extensors were assessed from repeated electrically evoked contractions on 2 separate days, with the use of a fixed dynamometer. Reliability was determined for fatigue resistance, rate of torque development (MRTD, and early and late relaxation time (RT50 and RT25, using the intraclass correlation coefficient (ICC and standard error of measurement (SEM, expressed as % of the mean.In both groups, reliability for fatigue resistance was good, with high ICCs (>0.90 and small SEM values (PPS: 7.1%, healthy individuals: 7.0%. Reliability for contractile speed indices varied, with the best values found for RT50 (ICCs>0.82, SEM values <2.8%. We found no systematic differences between test and retest occasions, except for RT50 in healthy subjects (p = 0.016.In PPS and healthy individuals, the reliability of fatigue resistance, as obtained from electrically evoked contractions is high. The reliability of contractile speed is only moderate, except for RT50 in PPS, demonstrating high reliability.This was the first study to examine the reliability of electrically evoked contractile properties in individuals with PPS. Our results demonstrate its potential to study mechanisms underlying muscle fatigue in PPS and to evaluate changes in contractile properties over time in response to interventions or from natural course.

  15. Human reliability data collection and modelling

    International Nuclear Information System (INIS)

    1991-09-01

    The main purpose of this document is to review and outline the current state-of-the-art of the Human Reliability Assessment (HRA) used for quantitative assessment of nuclear power plants safe and economical operation. Another objective is to consider Human Performance Indicators (HPI) which can alert plant manager and regulator to departures from states of normal and acceptable operation. These two objectives are met in the three sections of this report. The first objective has been divided into two areas, based on the location of the human actions being considered. That is, the modelling and data collection associated with control room actions are addressed first in chapter 1 while actions outside the control room (including maintenance) are addressed in chapter 2. Both chapters 1 and 2 present a brief outline of the current status of HRA for these areas, and major outstanding issues. Chapter 3 discusses HPI. Such performance indicators can signal, at various levels, changes in factors which influence human performance. The final section of this report consists of papers presented by the participants of the Technical Committee Meeting. A separate abstract was prepared for each of these papers. Refs, figs and tabs

  16. System Reliability of Timber Structures with Ductile Behaviour

    DEFF Research Database (Denmark)

    Kirkegaard, Poul Henning; Sørensen, John Dalsgaard; Čizmar, Dean

    2011-01-01

    The present paper considers the evaluation of timber structures with the focus on robustness due to connection ductility. The robustness analysis is based on the structural reliability framework applied to a simplified mechanical system. The structural timber system is depicted as a parallel system....... An evaluation method of the ductile behaviour is introduced. For different ductile behaviours, the system reliability is estimated based on Monte Carlo simulation. A correlation between the strength of the structural elements is introduced. The results indicate that the reliability of a structural timber system...

  17. Developing a System of National Climate Assessment Indicators to Track Climate Change Impacts, Vulnerabilities, and Preparedness

    Science.gov (United States)

    Janetos, A. C.; Kenney, M. A.; Chen, R. S.; Arndt, D.

    2012-12-01

    The National Climate Assessment (NCA) is being conducted under the auspices of the U.S. Global Change Research Program (USGCRP), pursuant to the Global Change Research Act of 1990, Section 106, which requires a report to Congress every 4 years (http://globalchange.gov/what-we-do/assessment/). Part of the vision for the sustained National Climate Assessment (NCA) process is a system of physical, ecological, and societal indicators that communicate key aspects of the physical climate, climate impacts, vulnerabilities, and preparedness for the purpose of informing both decision makers and the public with scientifically valid information that is useful to inform decision-making processes such as the development and implementation of climate adaptation strategies in a particular sector or region. These indicators will be tracked as a part of ongoing assessment activities, with adjustments as necessary to adapt to changing conditions and understanding. The indicators will be reviewed and updated so that the system adapts to new information. The NCA indicator system is not intended to serve as a vehicle for documenting rigorous cause and effect relationships. It is reasonable, however, for it to serve as a guide to those factors that affect the evolution of variability and change in the climate system, the resources and sectors of concern that are affected by it, and how society chooses to respond. Different components of the end-to-end climate issue serve as categories within which to organize an end-to-end system of indicators: Greenhouse Gas Emissions and Sinks Atmospheric Composition Physical Climate Variability and Change Sectors and Resources of Concern Adaptation and Mitigation Responses This framing has several advantages. It can be used to identify the different components of the end-to-end climate issue that both decision-makers and researchers are interested in. It is independent of scale, and therefore allows the indicators themselves to be described at

  18. The use of specialisation indices to predict vulnerability of coral-feeding butterflyfishes to environmental change

    KAUST Repository

    Lawton, Rebecca J.; Pratchett, Morgan S.; Berumen, Michael L.

    2011-01-01

    , the utility of these different indices to predict vulnerability to future environmental change is unknown. Here we compare the performance of specialisation indices using coral-feeding butterflyfishes as a model group. Our aims were to 1) quantify the dietary

  19. The use of invertebrates as indicators of environmental change in alpine rivers and lakes

    International Nuclear Information System (INIS)

    Khamis, K.; Hannah, D.M.; Brown, L.E.; Tiberti, R.; Milner, A.M.

    2014-01-01

    In alpine regions climatic change will alter the balance between water sources (rainfall, ice-melt, snowmelt, and groundwater) for aquatic systems, particularly modifying the relative contributions of meltwater, groundwater and rain to both rivers and lakes. While these changes are expected to have implications for alpine aquatic ecosystems, little is known about potential ecological tipping points and associated indicator taxa. We examined changes in biotic communities along a gradient of glacier influence for two study systems: (1) a stream network in the French Pyrénées; and (2) a network of lakes in the Italian Alps, with the aim of identifying potential indicator taxa (macroinvertebrates and zooplankton) of glacier retreat in these environments. To assess parallels in biotic responses across streams and lakes, both primary data and findings from other publications were synthesised. Using TITAN (Threshold Indicator Taxa ANalysis) changes in community composition of river taxa were identified at thresholds of < 5.1% glacier cover and < 66.6% meltwater contribution. Below these thresholds the loss of cold stenothermic benthic invertebrate taxa, Diamesa spp. and the Pyrenean endemic Rhyacophila angelieri was apparent. Some generalist taxa including Protonemura sp., Perla grandis, Baetis alpinus, Rhithrogena loyolaea and Microspectra sp. increased when glacier cover was < 2.7% and < 52% meltwater. Patterns were not as distinct for the alpine lakes, due to fewer sampling sites; however, Daphnia longispina grp. and the benthic invertebrate groups Plectopera and Planaria were identified as potential indicator taxa. While further work is required to assess potential indicator taxa for alpine lake systems, findings from alpine river systems were consistent between methods for assessing glacier influence (meltwater contribution/glacier cover). Hence, it is clear that TITAN could become a useful management tool, enabling: (i) the identification of taxa particularly

  20. The use of invertebrates as indicators of environmental change in alpine rivers and lakes

    Energy Technology Data Exchange (ETDEWEB)

    Khamis, K.; Hannah, D.M. [School of Geography Earth and Environmental Science, University of Birmingham, Birmingham B15 2TT (United Kingdom); Brown, L.E. [School of Geography/water@leeds, University of Leeds, Woodhouse Lane, Leeds LS2 9JT (United Kingdom); Tiberti, R. [DSTA, Dipartimento di Scienze della Terra e dell' Ambiente, University of Pavia, Via Ferrata 9, 27100 Pavia (Italy); Alpine Wildlife Research Centre, Gran Paradiso National Park, Degioz 11, I-1101 Valsavarenche, Aosta (Italy); Milner, A.M., E-mail: a.m.milner@bham.ac.uk [School of Geography Earth and Environmental Science, University of Birmingham, Birmingham B15 2TT (United Kingdom); Institute of Arctic Biology, University of Alaska, Fairbanks, AK 99775 (United States)

    2014-09-15

    In alpine regions climatic change will alter the balance between water sources (rainfall, ice-melt, snowmelt, and groundwater) for aquatic systems, particularly modifying the relative contributions of meltwater, groundwater and rain to both rivers and lakes. While these changes are expected to have implications for alpine aquatic ecosystems, little is known about potential ecological tipping points and associated indicator taxa. We examined changes in biotic communities along a gradient of glacier influence for two study systems: (1) a stream network in the French Pyrénées; and (2) a network of lakes in the Italian Alps, with the aim of identifying potential indicator taxa (macroinvertebrates and zooplankton) of glacier retreat in these environments. To assess parallels in biotic responses across streams and lakes, both primary data and findings from other publications were synthesised. Using TITAN (Threshold Indicator Taxa ANalysis) changes in community composition of river taxa were identified at thresholds of < 5.1% glacier cover and < 66.6% meltwater contribution. Below these thresholds the loss of cold stenothermic benthic invertebrate taxa, Diamesa spp. and the Pyrenean endemic Rhyacophila angelieri was apparent. Some generalist taxa including Protonemura sp., Perla grandis, Baetis alpinus, Rhithrogena loyolaea and Microspectra sp. increased when glacier cover was < 2.7% and < 52% meltwater. Patterns were not as distinct for the alpine lakes, due to fewer sampling sites; however, Daphnia longispina grp. and the benthic invertebrate groups Plectopera and Planaria were identified as potential indicator taxa. While further work is required to assess potential indicator taxa for alpine lake systems, findings from alpine river systems were consistent between methods for assessing glacier influence (meltwater contribution/glacier cover). Hence, it is clear that TITAN could become a useful management tool, enabling: (i) the identification of taxa particularly

  1. Effects of land use changes on eutrophication indicators in five coastal lagoons of the Southwestern Atlantic Ocean

    Science.gov (United States)

    Rodríguez-Gallego, Lorena; Achkar, Marcel; Defeo, Omar; Vidal, Leticia; Meerhoff, Erika; Conde, Daniel

    2017-03-01

    Five catchment areas in Uruguay were selected to conduct a nutrient exportation analysis and to evaluate the effects of current land use on the eutrophication of coastal lagoons. Satellite images and national agriculture censuses were used for a quantitative analysis of land use changes from 1974 to 2005, and a nutrient export coefficient approximation was used to determine long-term changes in annual loads. Several eutrophication indicators (water, sediment and autotrophic communities) were assessed seasonally in the lagoon basins during 2005 and 2006. The areal annual load of nutrients exported to the lagoons increased over time. Population and extensive livestock ranching were the most important nutrient sources, while agriculture is increasing in importance. Buffer effects of riparian forests on eutrophication indicators were observed in contrast to the wetlands surrounding the lagoons, which seem to be acting as a source of nutrients. Catchment size was inversely related to most eutrophication indicators. Afforestation and agriculture were found not to directly impact eutrophication indicators, however, catchments with larger agricultural areas showed higher concentrations of suspended solids, which may indicate the export of particulate nutrients. Salinity was inversely related to most eutrophication indicators, suggesting that the manipulation of the sand bar of the lagoons is a critical management issue. Sediment-related eutrophication indicators were more sensitive to changes in land uses and covers, in contrast with the more variable water column indicators, suggesting their potential use as enduring indicators. This research provides a rapid and integral assessment for qualitatively linking catchment changes with eutrophication indicators in coastal environments, which can easily be replicated to track pollutants in locations that lack standardized monitoring programs needed for more complex catchment modeling approaches.

  2. Measuring the effects of visual demand on lateral deviation: a comparison among driver's performance indicators.

    Science.gov (United States)

    Minin, Luca; Benedetto, Simone; Pedrotti, Marco; Re, Alessandra; Tesauri, Francesco

    2012-05-01

    In this study we compare the efficacy of three driver's performance indicators based on lateral deviation in detecting significant on-road performance degradations while interacting with a secondary task: the High Frequency Component of steering wheel (HFC), and two indicators described in ISO/DIS 26022 (2007): the Normative and the Adapted Lane Change Test (LCT). Sixteen participants were asked to perform a simulated lane-change task while interacting, when required, with a visual search task with two levels of difficulty. According to predictions, results showed that the Adapted LCT indicator, taking into consideration individual practices in performing the LCT, succeeded in discriminating between single and dual task conditions. Furthermore, this indicator was also able to detect whether the driver was interacting with an easy or a difficult secondary task. Despite predictions, results did not confirm Normative LCT and HFC to be reliable indicators of performance degradation within the simulated LCT. Copyright © 2011 Elsevier Ltd and The Ergonomics Society. All rights reserved.

  3. Computer scientist looks at reliability computations

    International Nuclear Information System (INIS)

    Rosenthal, A.

    1975-01-01

    Results from the theory of computational complexity are applied to reliability computations on fault trees and networks. A well known class of problems which almost certainly have no fast solution algorithms is presented. It is shown that even approximately computing the reliability of many systems is difficult enough to be in this class. In the face of this result, which indicates that for general systems the computation time will be exponential in the size of the system, decomposition techniques which can greatly reduce the effective size of a wide variety of realistic systems are explored

  4. Testing the Value of Information of Climate Change Indicators that use Earth Observations

    Science.gov (United States)

    Kenney, M. A.

    2012-12-01

    . Such a result would mean that the indicator has a negative value of information. Granted the value of information depends on the intended audience(s), with some groups being able to understand and want more technically sophisticated and detailed information presented as an indicator. However, if the goal of an indicator is to provide information to a wide range of groups, it is essential to assure that these groups have a correct understanding of the indicator, its assumptions, and the ability to use the indicator (as presented or modified) for decision-making contexts. In this talk, I will present the preliminary results of a study that is testing the value of information of a range of climate change indicators, and I will focus on indicators that use earth observations. Such results contribute to a richer understanding of the value of information of indicators, and can shape the development of both individual indicators and systems of indicators, such as the development of the indicator system for the U.S. Global Change Research Program, National Climate Assessment.

  5. Test-Retest Reliability and Minimal Detectable Change of the D2 Test of Attention in Patients with Schizophrenia.

    Science.gov (United States)

    Lee, Posen; Lu, Wen-Shian; Liu, Chin-Hsuan; Lin, Hung-Yu; Hsieh, Ching-Lin

    2017-12-08

    The d2 Test of Attention (D2) is a commonly used measure of selective attention for patients with schizophrenia. However, its test-retest reliability and minimal detectable change (MDC) are unknown in patients with schizophrenia, limiting its utility in both clinical and research settings. The aim of the present study was to examine the test-retest reliability and MDC of the D2 in patients with schizophrenia. A rater administered the D2 on 108 patients with schizophrenia twice at a 1-month interval. Test-retest reliability was determined through the calculation of the intra-class correlation coefficient (ICC). We also carried out Bland-Altman analysis, which included a scatter plot of the differences between test and retest against their mean. Systematic biases were evaluated by use of a paired t-test. The ICCs for the D2 ranged from 0.78 to 0.94. The MDCs (MDC%) of the seven subscores were 102.3 (29.7), 19.4 (85.0), 7.2 (94.6), 21.0 (69.0), 104.0 (33.1), 105.0 (35.8), and 7.8 (47.8), which represented limited-to-acceptable random measurement error. Trends in the Bland-Altman plots of the omissions (E1), commissions (E2), and errors (E) were noted, presenting that the data had heteroscedasticity. According to the results, the D2 had good test-retest reliability, especially in the scores of TN, TN-E, and CP. For the further research, finding a way to improve the administration procedure to reduce random measurement error would be important for the E1, E2, E, and FR subscores. © The Author(s) 2017. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  6. Techniques and applications of the human reliability analysis in nuclear facilities

    International Nuclear Information System (INIS)

    Pinto, Fausto C.

    1995-01-01

    The analysis and prediction of the man-machine interaction are the objectives of human reliability analysis. In this work is presented in a manner that could be used by experts in the field of Probabilistic Safety Assessment, considering primarily the aspects of human errors. The Technique of Human Error Rate Prediction (THERP) is used in large scale to obtain data on human error. Applications of this technique are presented, as well as aspects of the state-of-art and of research and development of this particular field of work, where the construction of a reliable data bank is considered essential. In this work is also developed an application of the THERP for the TRIGA Mark 1 IPR R-1 Reactor of the Centro de Desenvolvimento de Tecnologia Nuclear, Brazilian research institute of nuclear technology. The results indicate that some changes must be made in the emergency procedures of the reactor, in order to achieve a higher level of safety

  7. Quality indicators in subtropical soils of Formosa, Argentina: Changes for agriculturization process

    Directory of Open Access Journals (Sweden)

    Juan Esteban Baridón

    2014-12-01

    The changes produced in the Typic Hapludolls and Typic Argiudolls after 25 years of continuously using native forests, agriculture, fruit plantations and pastures were analyzed. These changes were in pH, electrical conductivity, total organic carbon, particulate organic carbon, total nitrogen, structural stability, hydraulic conductivity, respiration and dehydrogenase and urease and enzyme activity. Variables with significant differences between diverse uses were evaluated by multivariate methods, Principal Component Analysis, and Correlation Analysis. The results of this study showed that total organic carbon, particulate organic carbon, structural stability and dehydrogenase activity are the quality indicators most affected by agriculturization. All are related to organic matter.

  8. Network reliability assessment using a cellular automata approach

    International Nuclear Information System (INIS)

    Rocco S, Claudio M.; Moreno, Jose Ali

    2002-01-01

    Two cellular automata (CA) models that evaluate the s-t connectedness and shortest path in a network are presented. CA based algorithms enhance the performance of classical algorithms, since they allow a more reliable and straightforward parallel implementation resulting in a dynamic network evaluation, where changes in the connectivity and/or link costs can readily be incorporated avoiding recalculation from scratch. The paper also demonstrates how these algorithms can be applied for network reliability evaluation (based on Monte-Carlo approach) and for finding s-t path with maximal reliability

  9. Development of the Systems Thinking Scale for Adolescent Behavior Change.

    Science.gov (United States)

    Moore, Shirley M; Komton, Vilailert; Adegbite-Adeniyi, Clara; Dolansky, Mary A; Hardin, Heather K; Borawski, Elaine A

    2018-03-01

    This report describes the development and psychometric testing of the Systems Thinking Scale for Adolescent Behavior Change (STS-AB). Following item development, initial assessments of understandability and stability of the STS-AB were conducted in a sample of nine adolescents enrolled in a weight management program. Exploratory factor analysis of the 16-item STS-AB and internal consistency assessments were then done with 359 adolescents enrolled in a weight management program. Test-retest reliability of the STS-AB was .71, p = .03; internal consistency reliability was .87. Factor analysis of the 16-item STS-AB indicated a one-factor solution with good factor loadings, ranging from .40 to .67. Evidence of construct validity was supported by significant correlations with established measures of variables associated with health behavior change. We provide beginning evidence of the reliability and validity of the STS-AB to measure systems thinking for health behavior change in young adolescents.

  10. Reliability improvement through alternative designs-A case study

    International Nuclear Information System (INIS)

    Kumar, Saurabh; Chattopadhyay, Gopi; Kumar, Uday

    2007-01-01

    In today's competitive world, reliability of equipment is extremely important to maintain quality and delivery deadlines. This is achieved by using proper maintenance and design changes for unreliable subsystems and components of a complex system. It is significant to develop a strategy for maintenance, replacement and design changes related to those subsystems and components. An analysis of down time along with causes is essential to identify the unreliable components and subsystems. This paper presents an analysis of failure data of solenoid coils of automatic internal grinding machine used in a bearing manufacturing plant. It analyses various replacement and change of design options such as introduction of pneumatic system in place of electromagnetic solenoids for improvement of reliability of the plunger movement mechanism

  11. Integrating generation and transmission networks reliability for unit commitment solution

    International Nuclear Information System (INIS)

    Jalilzadeh, S.; Shayeghi, H.; Hadadian, H.

    2009-01-01

    This paper presents a new method with integration of generation and transmission networks reliability for the solution of unit commitment (UC) problem. In fact, in order to have a more accurate assessment of system reserve requirement, in addition to unavailability of generation units, unavailability of transmission lines are also taken into account. In this way, evaluation of the required spinning reserve (SR) capacity is performed by applying reliability constraints based on loss of load probability and expected energy not supplied (EENS) indices. Calculation of the above parameters is accomplished by employing a novel procedure based on the linear programming which it also minimizes them to achieve optimum level of the SR capacity and consequently a cost-benefit reliability constrained UC schedule. In addition, a powerful solution technique called 'integer-coded genetic algorithm (ICGA)' is being used for the solution of the proposed method. Numerical results on the IEEE reliability test system show that the consideration of transmission network unavailability has an important influence on reliability indices of the UC schedules

  12. Intra-Subject Consistency and Reliability of Response Following 2 mA Transcranial Direct Current Stimulation.

    Science.gov (United States)

    Dyke, Katherine; Kim, Soyoung; Jackson, Georgina M; Jackson, Stephen R

    Transcranial direct current stimulation (tDCS) is a popular non-invasive brain stimulation technique that has been shown to influence cortical excitability. While polarity specific effects have often been reported, this is not always the case, and variability in both the magnitude and direction of the effects have been observed. We aimed to explore the consistency and reliability of the effects of tDCS by investigating changes in cortical excitability across multiple testing sessions in the same individuals. A within subjects design was used to investigate the effects of anodal and cathodal tDCS applied to the motor cortex. Four experimental sessions were tested for each polarity in addition to two sham sessions. Transcranial magnetic stimulation (TMS) was used to measure cortical excitability (TMS recruitment curves). Changes in excitability were measured by comparing baseline measures and those taken immediately following 20 minutes of 2 mA stimulation or sham stimulation. Anodal tDCS significantly increased cortical excitability at a group level, whereas cathodal tDCS failed to have any significant effects. The sham condition also failed to show any significant changes. Analysis of intra-subject responses to anodal stimulation across four sessions suggest that the amount of change in excitability across sessions was only weakly associated, and was found to have poor reliability across sessions (ICC = 0.276). The effects of cathodal stimulation show even poorer reliability across sessions (ICC = 0.137). In contrast ICC analysis for the two sessions of sham stimulation reflect a moderate level of reliability (ICC = .424). Our findings indicate that although 2 mA anodal tDCS is effective at increasing cortical excitability at group level, the effects are unreliable across repeated testing sessions within individual participants. Our results suggest that 2 mA cathodal tDCS does not significantly alter cortical excitability immediately following

  13. Reliability criteria selection for integrated resource planning

    International Nuclear Information System (INIS)

    Ruiu, D.; Ye, C.; Billinton, R.; Lakhanpal, D.

    1993-01-01

    A study was conducted on the selection of a generating system reliability criterion that ensures a reasonable continuity of supply while minimizing the total costs to utility customers. The study was conducted using the Institute for Electronic and Electrical Engineers (IEEE) reliability test system as the study system. The study inputs and results for conditions and load forecast data, new supply resources data, demand-side management resource data, resource planning criterion, criterion value selection, supply side development, integrated resource development, and best criterion values, are tabulated and discussed. Preliminary conclusions are drawn as follows. In the case of integrated resource planning, the selection of the best value for a given type of reliability criterion can be done using methods similar to those used for supply side planning. The reliability criteria values previously used for supply side planning may not be economically justified when integrated resource planning is used. Utilities may have to revise and adopt new, and perhaps lower supply reliability criteria for integrated resource planning. More complex reliability criteria, such as energy related indices, which take into account the magnitude, frequency and duration of the expected interruptions are better adapted than the simpler capacity-based reliability criteria such as loss of load expectation. 7 refs., 5 figs., 10 tabs

  14. TEST-RETEST RELIABILITY OF THE CLOSED KINETIC CHAIN UPPER EXTREMITY STABILITY TEST (CKCUEST) IN ADOLESCENTS: RELIABILITY OF CKCUEST IN ADOLESCENTS.

    Science.gov (United States)

    de Oliveira, Valéria M A; Pitangui, Ana C R; Nascimento, Vinícius Y S; da Silva, Hítalo A; Dos Passos, Muana H P; de Araújo, Rodrigo C

    2017-02-01

    The Closed Kinetic Chain Upper Extremity Stability Test (CKCUEST) has been proposed as an option to assess upper limb function and stability; however, there are few studies that support the use of this test in adolescents. The purpose of the present study was to investigate the intersession reliability and agreement of three CKCUEST scores in adolescents and establish clinimetric values for this test. Test-retest reliability. Twenty-five healthy adolescents of both sexes were evaluated. The subjects performed two CKCUEST with an interval of one week between the tests. An intraclass correlation coefficient (ICC 3,3 ) two-way mixed model with a 95% interval of confidence was utilized to determine intersession reliability. A Bland-Altman graph was plotted to analyze the agreement between assessments. The presence of systematic error was evaluated by a one-sample t test. The difference between the evaluation and reevaluation was observed using a paired-sample t test. The level of significance was set at 0.05. Standard error of measurements and minimum detectable changes were calculated. The intersession reliability of the average touches score, normalized score, and power score were 0.68, 0.68 and 0.87, the standard error of measurement were 2.17, 1.35 and 6.49, and the minimal detectable change was 6.01, 3.74 and 17.98, respectively. The presence of systematic error (p test with moderate to excellent reliability when used with adolescents. The CKCUEST is a measurement with moderate to excellent reliability for adolescents. 2b.

  15. Reliability and Agreement in Student Ratings of the Class Environment

    Science.gov (United States)

    Nelson, Peter M.; Christ, Theodore J.

    2016-01-01

    The current study estimated the reliability and agreement of student ratings of the classroom environment obtained using the Responsive Environmental Assessment for Classroom Teaching (REACT; Christ, Nelson, & Demers, 2012; Nelson, Demers, & Christ, 2014). Coefficient alpha, class-level reliability, and class agreement indices were…

  16. Indicator value of lotic water mites (Acari: Hydrachnidia and their use in macroinvertebrate-based indices for water quality assessment purposes

    Directory of Open Access Journals (Sweden)

    Miccoli F. P.

    2013-10-01

    Full Text Available The Water Framework Directive (WFD of the European Union includes benthic macroinvertebrates for the ecological assessment of running waters. The invertebrate-based Star-ICMi index, adopted in 2010, does not include Hydrachnidia (water mites in its complex formulation. However, Hydrachnidia are associated with many environmental variables and may be useful for stream ecological characterization. We have therefore assessed the bioindicator value of Hydrachnidia in streams of central Italy, and the ability of two mite-containing (the PTH and the newly formulated PTHfam indices and four mite-excluding biotic indices (Star-ICMi, BMWP, ASPT, and IBE to characterize 216 sites ranging from semipristine to impacted. Mite bioindicator value was high at family level. Index reliability was consistently low for the PTH and ASPT indices. Distribution of mite families across quality classes (QCs was fully separated only for the PTHfam index. QC assignment remained reliable at high index values (i.e., at high ecological status for the PTHfam and BMWP indices, while logarithmic correlations between the PTHfam and the other indices suggest that the latter may misrepresent sites in high, good, and moderate ecological status sensu WFD. Further studies on the PTHfam index are warranted in light of its simplicity, high reliability, and low sampling and taxonomic identification effort.

  17. Feasibility Study of a Simulation Driven Approach for Estimating Reliability of Wind Turbine Fluid Power Pitch Systems

    DEFF Research Database (Denmark)

    Liniger, Jesper; Pedersen, Henrik Clemmensen; N. Soltani, Mohsen

    2018-01-01

    Recent field data indicates that pitch systems account for a substantial part of a wind turbines down time. Reducing downtime means increasing the total amount of energy produced during its lifetime. Both electrical and fluid power pitch systems are employed with a roughly 50/50 distribution. Fluid...... power pitch systems generally show higher reliability and have been favored on larger offshore wind turbines. Still general issues such as leakage, contamination and electrical faults make current systems work sub-optimal. Current field data for wind turbines present overall pitch system reliability...... and the reliability of component groups (valves, accumulators, pumps etc.). However, the failure modes of the components and more importantly the root causes are not evident. The root causes and failure mode probabilities are central for changing current pitch system designs and operational concepts to increase...

  18. Regulatory and personality predictors of the reliability of professional actions

    Directory of Open Access Journals (Sweden)

    Morosanova V.I.

    2017-12-01

    Full Text Available Background. The present research is carried out in the context of the conscious self-regulation of professional activity. Objective. It investigates the regulatory and personality predictors of reliability in rescue operations under stressful conditions. Design. The research sample includes 87 rescuers (72 men and 15 women aged from 25 to 50 years. Respondents were asked to complete the Morosanova’s Self-Regulation Profile Questionnaire – SRPQM, the Eysenck Personality Profile - Short (EPP-S, and the expert questionnaire “Professional Reliability of Rescue Operation” designed for this particular study. Results. On the basis of a correlation analysis, the structural model of the predictors of action reliability was constructed using the maximum likelihood method. Consistency indices showed a good agreement between the model and empirical data. The model contains three latent factors: “Self-regulation”, “Neuroticism” and “Reliability of actions”. As the model displays, the “Self-regulation” factor is a significant predictor of professional action reliability. There are two indicator variables for the factor “Self-regulation”: the self-regulation reliability considered as its stability in the stressful situations, and the rescuers’ levels of development of professionally critical regulatory features - modeling of conditions significant for the achievement of goals and the programming of actions. The study results also show that personality dispositions (by Eysenck have only indirect influence on action reliability. As the structural model reveals, the conscious self-regulation is a mediator in the relationship of neuroticism traits and action reliability. Conclusion. The conscious self-regulation is a significant predictor of professional action reliability under stressful conditions. It is also the mediator of the effects of personality dispositions on the reliability of action.

  19. Ultrasound changes in the relationship between the urethra and bladder neck caused by prolapse repair: feasibility and reliability of measurements.

    Science.gov (United States)

    Duckett, J; Lautmann, K

    2012-10-01

    The objective of this study was to assess whether intraoperative transperineal ultrasound can be used to assess changes in the relationship between the urethra and bladder caused by a prolapse repair operation. The reliability of the measurements was also assessed. A total of 25 women having an anterior colporrhaphy operation had pre- and post-repair imaging using a standard bladder volume. There was a statistically significant change (p ≤ 0.04) in the posterior urethrovesical angle (PUA) from 115° (SD 37) before surgery, to 135° (SD 30) after surgery. There was no significant change (p = 0.93) in the anterior urethrovesical angle before 73° (SD 14) after surgery 73° (SD 14). Interclass correlation coefficients showed good reproducibility for all measurements. Ultrasound can be used to measure changes in the relationship of the urethra and bladder produced by anterior colporrhaphy. Clinically, the effect of these changes is to reduce the angulation of the urethra in relation to the bladder.

  20. A framework for reliability and risk centered maintenance

    International Nuclear Information System (INIS)

    Selvik, J.T.; Aven, T.

    2011-01-01

    Reliability centered maintenance (RCM) is a well-established analysis method for preventive maintenance planning. As its name indicates, reliability is the main point of reference for the planning, but consequences of failures are also assessed. However, uncertainties and risk are to a limited extent addressed by the RCM method, and in this paper we suggest an extension of the RCM to reliability and risk centered maintenance (RRCM) by also considering risk as the reference for the analysis in addition to reliability. A broad perspective on risk is adopted where uncertainties are the main component of risk in addition to possible events and associated consequences. A case from the offshore oil and gas industry is presented to illustrate and discuss the suggested approach.

  1. Power system reliability enhancement by using PowerformerTM

    Directory of Open Access Journals (Sweden)

    Rahmat-Allah Hooshmand

    2009-01-01

    Full Text Available A high-voltage generator PowerformerTM is a new generation of the AC generators. The most significant advantages of these PowerformerTM are their direct connection to high-voltage grid, higher availability, and more reactive power margin, short term overloading capacity and removing the power transformer from the structure of the power plant. In this paper, the installation effect of these generators on the power system reliability is investigated. The amount of the effects depends on the type and location of the power plant, location of the PowerformerTM, the size of load and network topology. For this purpose, in the 6-bus IEEE RBTS system, the conventional generators are replaced by these new PowerformerTM and then, the reliability indices are evaluated. The simulation results show that the reliability indices such as the expected duration of load curtailment (EDLC and the expected energy not served (EENS are improved. .

  2. Psychometric analysis of the TRANSIT quality indicators for cardiovascular disease prevention in primary care.

    Science.gov (United States)

    Khanji, Cynthia; Bareil, Céline; Hudon, Eveline; Goudreau, Johanne; Duhamel, Fabie; Lussier, Marie-Thérèse; Perreault, Sylvie; Lalonde, Gilles; Turcotte, Alain; Berbiche, Djamal; Martin, Élisabeth; Lévesque, Lise; Gagnon, Marie-Mireille; Lalonde, Lyne

    2017-12-01

    To assess a selection of psychometric properties of the TRANSIT indicators. Using medical records, indicators were documented retrospectively during the 14 months preceding the end of the TRANSIT study. Primary care in Quebec, Canada. Indicators were documented in a random subsample (n = 123 patients) of the TRANSIT study population (n = 759). For every patient, the mean compliance to all indicators of a category (subscale score) and to the complete set of indicators (overall scale score) were established. To evaluate test-retest and inter-rater reliabilities, indicators were applied twice, two months apart, by the same evaluator and independently by different evaluators, respectively. To evaluate convergent validity, correlations between TRANSIT indicators, Burge et al. indicators and Institut national d'excellence en santé et en services sociaux (INESSS) indicators were examined. Test-retest reliability, inter-rater reliability, and convergent validity. Test-retest reliability, as measured by intraclass correlation coefficients (ICCs) was equal to 0.99 (0.99-0.99) for the overall scale score while inter-rater reliability was equal to 0.95 (0.93-0.97) for the overall scale score. Convergent validity, as measured by Pearson's correlation coefficients, was equal to 0.77 (P TRANSIT indicators were compared to Burge et al. indicators and to 0.82 (P TRANSIT indicators were compared to INESSS indicators. Reliability was excellent except for eleven indicators while convergent validity was strong except for domains related to the management of CVD risk factors. © The Author 2017. Published by Oxford University Press in association with the International Society for Quality in Health Care. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com

  3. Modeling of seismic hazards for dynamic reliability analysis

    International Nuclear Information System (INIS)

    Mizutani, M.; Fukushima, S.; Akao, Y.; Katukura, H.

    1993-01-01

    This paper investigates the appropriate indices of seismic hazard curves (SHCs) for seismic reliability analysis. In the most seismic reliability analyses of structures, the seismic hazards are defined in the form of the SHCs of peak ground accelerations (PGAs). Usually PGAs play a significant role in characterizing ground motions. However, PGA is not always a suitable index of seismic motions. When random vibration theory developed in the frequency domain is employed to obtain statistics of responses, it is more convenient for the implementation of dynamic reliability analysis (DRA) to utilize an index which can be determined in the frequency domain. In this paper, we summarize relationships among the indices which characterize ground motions. The relationships between the indices and the magnitude M are arranged as well. In this consideration, duration time plays an important role in relating two distinct class, i.e. energy class and power class. Fourier and energy spectra are involved in the energy class, and power and response spectra and PGAs are involved in the power class. These relationships are also investigated by using ground motion records. Through these investigations, we have shown the efficiency of employing the total energy as an index of SHCs, which can be determined in the time and frequency domains and has less variance than the other indices. In addition, we have proposed the procedure of DRA based on total energy. (author)

  4. Reliable Ant Colony Routing Algorithm for Dual-Channel Mobile Ad Hoc Networks

    Directory of Open Access Journals (Sweden)

    YongQiang Li

    2018-01-01

    Full Text Available For the problem of poor link reliability caused by high-speed dynamic changes and congestion owing to low network bandwidth in ad hoc networks, an ant colony routing algorithm, based on reliable path under dual-channel condition (DSAR, is proposed. First, dual-channel communication mode is used to improve network bandwidth, and a hierarchical network model is proposed to optimize the dual-layer network. Thus, we reduce network congestion and communication delay. Second, a comprehensive reliable path selection strategy is designed, and the reliable path is selected ahead of time to reduce the probability of routing restart. Finally, the ant colony algorithm is used to improve the adaptability of the routing algorithm to changes of network topology. Simulation results show that DSAR improves the reliability of routing, packet delivery, and throughput.

  5. Neural Correlates of Indicators of Sound Change in Cantonese: Evidence from Cortical and Subcortical Processes.

    Science.gov (United States)

    Maggu, Akshay R; Liu, Fang; Antoniou, Mark; Wong, Patrick C M

    2016-01-01

    Across time, languages undergo changes in phonetic, syntactic, and semantic dimensions. Social, cognitive, and cultural factors contribute to sound change, a phenomenon in which the phonetics of a language undergo changes over time. Individuals who misperceive and produce speech in a slightly divergent manner (called innovators ) contribute to variability in the society, eventually leading to sound change. However, the cause of variability in these individuals is still unknown. In this study, we examined whether such misperceptions are represented in neural processes of the auditory system. We investigated behavioral, subcortical (via FFR), and cortical (via P300) manifestations of sound change processing in Cantonese, a Chinese language in which several lexical tones are merging. Across the merging categories, we observed a similar gradation of speech perception abilities in both behavior and the brain (subcortical and cortical processes). Further, we also found that behavioral evidence of tone merging correlated with subjects' encoding at the subcortical and cortical levels. These findings indicate that tone-merger categories, that are indicators of sound change in Cantonese, are represented neurophysiologically with high fidelity. Using our results, we speculate that innovators encode speech in a slightly deviant neurophysiological manner, and thus produce speech divergently that eventually spreads across the community and contributes to sound change.

  6. Identifying individual changes in performance with composite quality indicators while accounting for regression to the mean.

    Science.gov (United States)

    Gajewski, Byron J; Dunton, Nancy

    2013-04-01

    Almost a decade ago Morton and Torgerson indicated that perceived medical benefits could be due to "regression to the mean." Despite this caution, the regression to the mean "effects on the identification of changes in institutional performance do not seem to have been considered previously in any depth" (Jones and Spiegelhalter). As a response, Jones and Spiegelhalter provide a methodology to adjust for regression to the mean when modeling recent changes in institutional performance for one-variable quality indicators. Therefore, in our view, Jones and Spiegelhalter provide a breakthrough methodology for performance measures. At the same time, in the interests of parsimony, it is useful to aggregate individual quality indicators into a composite score. Our question is, can we develop and demonstrate a methodology that extends the "regression to the mean" literature to allow for composite quality indicators? Using a latent variable modeling approach, we extend the methodology to the composite indicator case. We demonstrate the approach on 4 indicators collected by the National Database of Nursing Quality Indicators. A simulation study further demonstrates its "proof of concept."

  7. Operational and reliability experience with reactor instrumentation

    International Nuclear Information System (INIS)

    Dixon, F.; Gow, R.S.

    1978-01-01

    In the last 15 years the CEGB has experienced progressive plant development, integration and changes in operating regime through nine nuclear (gas-cooled reactor) power stations with corresponding instrumentation advances leading towards more refined centralized control. Operation and reliability experience with reactor instrumentation is reported in this paper with reference to the progressive changes related to the early magnox, late magnox and AGR periods. Data on instrumentation reliability in terms of reactor forced outages are presented and show that the instrumentation contributions to loss of generating plant availability are small. Reactor safety circuits, neutron flux and temperature measurements, gas analysis and vibration monitoring are discussed. In reviewing the reactor instrumentation the emphasis is on reporting recent experience, particularly on AGR equipment, but overall performance and changes to magnox equipment are included so that some appreciation can be obtained of instrumentation requirements with respect to plant lifetimes. (author)

  8. Is the Bayley Scales of Infant and Toddler Developmental Screening Test, Valid and Reliable for Persian Speaking Children?

    Science.gov (United States)

    Soleimani, Farin; Azari, Nadia; Vameghi, Roshanak; Sajedi, Firoozeh; Shahshahani, Soheila; Karimi, Hossein; Kraskian, Adis; Shahrokhi, Amin; Teymouri, Robab; Gharib, Masoud

    2016-10-01

    Advances in perinatal and neonatal care have substantially improved the survival of at-risk infants over the past two decades. The purpose of this study was to assess the reliability and validity of the Bayley Scales of infant and toddler developmental Screening test in Persian-speaking children. This was a cross-sectional prospective study of 403 children aged 1 - 42-months. The Bayley scales screening instrument, which consists of five domains (cognitive, receptive, and expressive communication and fine and gross motor items), was used to measure infants' and toddlers' development. The psychometric properties examined included the face and content validity of the scale, in addition to cultural and linguistic modifications to the scale and its test-retest and inter-rater reliability. An expert team changed some of the test items relating to cultural and linguistic issues. In almost all the age groups, cultural or linguistic changes were made to items in the communication domains. According to Cronbach's alpha for internal consistency, the reliability of the cognitive scale was r = 0.79, and the reliability of the receptive scale was r = 0.76. The reliability for expressive communication, fine motor, and gross motor scales was r = 0.81, r = 0.80, and r = 0.81, respectively. The construct validity of the tests was confirmed using a factor analysis and comparison of the mean scores of the age groups. The intra- and inter-rater reliabilities of the Bayley Scales were good-to-excellent. The results indicated that the Bayley Scales had a high level of reliability in the present study. Thus, the scale can be used in a Persian population.

  9. Reliability and validity of a Mental Health System Responsiveness Questionnaire in Iran

    Directory of Open Access Journals (Sweden)

    Ameneh S. Forouzan

    2014-07-01

    Full Text Available Background: The Health System Responsiveness Questionnaire is an instrument designed by the World Health Organization (WHO in 2000 to assess the experience of patients when interacting with the health care system. This investigation aimed to adapt a Mental Health System Responsiveness Questionnaire (MHSRQ based on the WHO concept and evaluate its validity and reliability to the mental health care system in Iran. Design: In accordance with the WHO health system responsiveness questionnaire and the findings of a qualitative study, a Farsi version of the MHSRQ was tailored to suit the mental health system in Iran. This version was tested in a cross-sectional study at nine public mental health clinics in Tehran. A sample of 500 mental health services patients was recruited and subsequently completed the questionnaire. Item missing rate was used to check the feasibility while the reliability of the scale was determined by assessing the Cronbach's alpha and item total correlations. The factor structure of the questionnaire was investigated by performing confirmatory factor analysis (CFA. Results: The results showed a satisfactory feasibility since the item missing value was lower than 5.2%. With the exception of access domain, reliability of different domains of the questionnaire was within a desirable range. The factor loading showed an acceptable unidimentionality of the scale despite the fact that three items related to access did not perform well. The CFA also indicated good fit indices for the model (CFI=0.99, GFI=0.97, IFI=0.99, AGFI=0.97. Conclusions: In general, the findings suggest that the Farsi version of the MHSRQ is a feasible, reliable, and valid measure of the mental health system responsiveness in Iran. Changes to the questions related to the access domain should be considered in order to improve the psychometric properties of the measure.

  10. Network based early warning indicators of vegetation changes in a land–atmosphere model

    NARCIS (Netherlands)

    Yin, Z.; Dekker, S.C.; Rietkerk, M.; Hurk, B.J.J.M. van den; Dijkstra, H.A.

    2016-01-01

    Abstract Numerous model studies demonstrate that ecosystems might not shift smoothly with a gradual change in resource concentration. At specific points, vegetation can suddenly shift from one stable state to another. To predict such undesirable shifts, statistical indicators are proposed for early

  11. Accident Sequence Evaluation Program: Human reliability analysis procedure

    International Nuclear Information System (INIS)

    Swain, A.D.

    1987-02-01

    This document presents a shortened version of the procedure, models, and data for human reliability analysis (HRA) which are presented in the Handbook of Human Reliability Analysis With emphasis on Nuclear Power Plant Applications (NUREG/CR-1278, August 1983). This shortened version was prepared and tried out as part of the Accident Sequence Evaluation Program (ASEP) funded by the US Nuclear Regulatory Commission and managed by Sandia National Laboratories. The intent of this new HRA procedure, called the ''ASEP HRA Procedure,'' is to enable systems analysts, with minimal support from experts in human reliability analysis, to make estimates of human error probabilities and other human performance characteristics which are sufficiently accurate for many probabilistic risk assessments. The ASEP HRA Procedure consists of a Pre-Accident Screening HRA, a Pre-Accident Nominal HRA, a Post-Accident Screening HRA, and a Post-Accident Nominal HRA. The procedure in this document includes changes made after tryout and evaluation of the procedure in four nuclear power plants by four different systems analysts and related personnel, including human reliability specialists. The changes consist of some additional explanatory material (including examples), and more detailed definitions of some of the terms. 42 refs

  12. Critical Assessment of the Foundations of Power Transmission and Distribution Reliability Metrics and Standards.

    Science.gov (United States)

    Nateghi, Roshanak; Guikema, Seth D; Wu, Yue Grace; Bruss, C Bayan

    2016-01-01

    The U.S. federal government regulates the reliability of bulk power systems, while the reliability of power distribution systems is regulated at a state level. In this article, we review the history of regulating electric service reliability and study the existing reliability metrics, indices, and standards for power transmission and distribution networks. We assess the foundations of the reliability standards and metrics, discuss how they are applied to outages caused by large exogenous disturbances such as natural disasters, and investigate whether the standards adequately internalize the impacts of these events. Our reflections shed light on how existing standards conceptualize reliability, question the basis for treating large-scale hazard-induced outages differently from normal daily outages, and discuss whether this conceptualization maps well onto customer expectations. We show that the risk indices for transmission systems used in regulating power system reliability do not adequately capture the risks that transmission systems are prone to, particularly when it comes to low-probability high-impact events. We also point out several shortcomings associated with the way in which regulators require utilities to calculate and report distribution system reliability indices. We offer several recommendations for improving the conceptualization of reliability metrics and standards. We conclude that while the approaches taken in reliability standards have made considerable advances in enhancing the reliability of power systems and may be logical from a utility perspective during normal operation, existing standards do not provide a sufficient incentive structure for the utilities to adequately ensure high levels of reliability for end-users, particularly during large-scale events. © 2015 Society for Risk Analysis.

  13. Reliability of White Matter Microstructural Changes in HIV Infection: Metaanalysis and Confirmation

    Science.gov (United States)

    O’Connor, Erin E.; Jaillard, Assia; Renard, Felix; Zeffiro, Thomas A.

    2017-01-01

    Background Diffusion tensor imaging (DTI) has been widely used to measure HIV effects on white matter (WM) microarchitecture. While many have reported reduced fractional anisotropy (FA) and increased mean diffusivity (MD) in HIV, quantitative inconsistencies across studies are large. Purpose To evaluate the consistency across studies of HIV effects on DTI measures and then examine DTI reliability in a longitudinal seropositive cohort. Study Selection The meta-analysis included 16 cross-sectional studies reporting FA and 12 studies reporting MD in the corpus callosum. Data Analysis Random effects meta-analysis was used to estimate study standardized mean differences (smd) and heterogeneity. DTI longitudinal reliability was estimated in seropositives studied before, and three and six months after, beginning treatment. Data Synthesis Meta-analysis revealed lower FA (smd −0.43; psmd 0.44; p0.96. Limitation Many studies pooled participants with varying treatments, ages and disease durations. Conclusion HIV effects on WM microstructure exhibited substantial variations that could result from acquisition, processing or cohort selection differences. When acquisition parameters and processing were carefully controlled, the resulting DTI measures did not show high temporal variation. HIV effects on WM microstructure may be age dependent. The high longitudinal reliability of DTI WM microstructure measures make them promising disease activity markers. PMID:28596189

  14. Climate change scenarios and key climate indices in the Swiss Alpine region

    Science.gov (United States)

    Zubler, Elias; Croci-Maspoli, Mischa; Frei, Christoph; Liniger, Mark; Scherrer, Simon; Appenzeller, Christof

    2013-04-01

    For climate adaption and to support climate mitigation policy it is of outermost importance to demonstrate the consequences of climate change on a local level and in user oriented quantities. Here, a framework is presented to apply the Swiss national climate change scenarios CH2011 to climate indices with direct relevance to applications, such as tourism, transportation, agriculture and health. This framework provides results on a high spatial and temporal resolution and can also be applied in mountainous regions such as the Alps. Results are shown for some key indices, such as the number of summer days and tropical nights, growing season length, number of frost days, heating and cooling degree days, and the number of days with fresh snow. Particular focus is given to changes in the vertical distribution for the future periods 2020-2049, 2045-2074 and 2070-2099 relative to the reference period 1980-2009 for the A1B, A2 and RCP3PD scenario. The number of days with fresh snow is approximated using a combination of temperature and precipitation as proxies. Some findings for the latest scenario period are: (1) a doubling of the number of summer days by the end of the century under the business-as-usual scenario A2, (2) tropical nights appear above 1500 m asl, (3) the number of frost days may be reduced by more than 3 months at altitudes higher than 2500 m, (4) an overall reduction of heating degree days of about 30% by the end of the century, but on the other hand an increase in cooling degree days in warm seasons, and (5) the number of days with fresh snow tends to go towards zero at low altitudes. In winter, there is little change in snowfall above 2000 m asl (roughly -3 days) in all scenarios. The largest impact on snowfall is found along the Northern Alpine flank and the Jura (-10 days or roughly -50% in A1B for the winter season). It is also highlighted that the future projections for all indices strongly depend on the chosen scenario and on model uncertainty

  15. Reliability measures of functional magnetic resonance imaging in a longitudinal evaluation of mild cognitive impairment.

    Science.gov (United States)

    Zanto, Theodore P; Pa, Judy; Gazzaley, Adam

    2014-01-01

    As the aging population grows, it has become increasingly important to carefully characterize amnestic mild cognitive impairment (aMCI), a preclinical stage of Alzheimer's disease (AD). Functional magnetic resonance imaging (fMRI) is a valuable tool for monitoring disease progression in selectively vulnerable brain regions associated with AD neuropathology. However, the reliability of fMRI data in longitudinal studies of older adults with aMCI is largely unexplored. To address this, aMCI participants completed two visual working tasks, a Delayed-Recognition task and a One-Back task, on three separate scanning sessions over a three-month period. Test-retest reliability of the fMRI blood oxygen level dependent (BOLD) activity was assessed using an intraclass correlation (ICC) analysis approach. Results indicated that brain regions engaged during the task displayed greater reliability across sessions compared to regions that were not utilized by the task. During task-engagement, differential reliability scores were observed across the brain such that the frontal lobe, medial temporal lobe, and subcortical structures exhibited fair to moderate reliability (ICC=0.3-0.6), while temporal, parietal, and occipital regions exhibited moderate to good reliability (ICC=0.4-0.7). Additionally, reliability across brain regions was more stable when three fMRI sessions were used in the ICC calculation relative to two fMRI sessions. In conclusion, the fMRI BOLD signal is reliable across scanning sessions in this population and thus a useful tool for tracking longitudinal change in observational and interventional studies in aMCI. © 2013.

  16. Suprahyoid Muscle Complex: A Reliable Neural Assessment Tool For Dysphagia?

    DEFF Research Database (Denmark)

    Kothari, Mohit; Stubbs, Peter William; Pedersen, Asger Roer

    be a non-invasive reliable neural assessment tool for patients with dysphagia. Objective: To investigate the possibility of using the suprahyoid muscle complex (SMC) using surface electromyography (sEMG) to assess changes to neural pathways by determining the reliability of measurements in healthy...

  17. Validity and Reliability of Farsi Version of Youth Sport Environment Questionnaire.

    Science.gov (United States)

    Eshghi, Mohammad Ali; Kordi, Ramin; Memari, Amir Hossein; Ghaziasgar, Ahmad; Mansournia, Mohammad-Ali; Zamani Sani, Seyed Hojjat

    2015-01-01

    The Youth Sport Environment Questionnaire (YSEQ) had been developed from Group Environment Questionnaire, a well-known measure of team cohesion. The aim of this study was to adapt and examine the reliability and validity of the Farsi version of the YSEQ. This version was completed by 455 athletes aged 13-17 years. Results of confirmatory factor analysis indicated that two-factor solution showed a good fit to the data. The results also revealed that the Farsi YSEQ showed high internal consistency, test-retest reliability, and good concurrent validity. This study indicated that the Farsi version of the YSEQ is a valid and reliable measure to assess team cohesion in sport setting.

  18. PCA as a practical indicator of OPLS-DA model reliability.

    Science.gov (United States)

    Worley, Bradley; Powers, Robert

    Principal Component Analysis (PCA) and Orthogonal Projections to Latent Structures Discriminant Analysis (OPLS-DA) are powerful statistical modeling tools that provide insights into separations between experimental groups based on high-dimensional spectral measurements from NMR, MS or other analytical instrumentation. However, when used without validation, these tools may lead investigators to statistically unreliable conclusions. This danger is especially real for Partial Least Squares (PLS) and OPLS, which aggressively force separations between experimental groups. As a result, OPLS-DA is often used as an alternative method when PCA fails to expose group separation, but this practice is highly dangerous. Without rigorous validation, OPLS-DA can easily yield statistically unreliable group separation. A Monte Carlo analysis of PCA group separations and OPLS-DA cross-validation metrics was performed on NMR datasets with statistically significant separations in scores-space. A linearly increasing amount of Gaussian noise was added to each data matrix followed by the construction and validation of PCA and OPLS-DA models. With increasing added noise, the PCA scores-space distance between groups rapidly decreased and the OPLS-DA cross-validation statistics simultaneously deteriorated. A decrease in correlation between the estimated loadings (added noise) and the true (original) loadings was also observed. While the validity of the OPLS-DA model diminished with increasing added noise, the group separation in scores-space remained basically unaffected. Supported by the results of Monte Carlo analyses of PCA group separations and OPLS-DA cross-validation metrics, we provide practical guidelines and cross-validatory recommendations for reliable inference from PCA and OPLS-DA models.

  19. Development and pilot test of a new set of good practice indicators for chronic cancer pain management.

    Science.gov (United States)

    Saturno, P J; Martinez-Nicolas, I; Robles-Garcia, I S; López-Soriano, F; Angel-García, D

    2015-01-01

    Pain is among the most important symptoms in terms of prevalence and cause of distress for cancer patients and their families. However, there is a lack of clearly defined measures of quality pain management to identify problems and monitor changes in improvement initiatives. We built a comprehensive set of evidence-based indicators following a four-step model: (1) review and systematization of existing guidelines to list evidence-based recommendations; (2) review and systematization of existing indicators matching the recommendations; (3) development of new indicators to complete a set of measures for the identified recommendations; and (4) pilot test (in hospital and primary care settings) for feasibility, reliability (kappa), and usefulness for the identification of quality problems using the lot quality acceptance sampling (LQAS) method and estimates of compliance. Twenty-two indicators were eventually pilot tested. Seventeen were feasible in hospitals and 12 in all settings. Feasibility barriers included difficulties in identifying target patients, deficient clinical records and low prevalence of cases for some indicators. Reliability was mostly very good or excellent (k > 0.8). Four indicators, all of them related to medication and prevention of side effects, had acceptable compliance at 75%/40% LQAS level. Other important medication-related indicators (i.e., adjustment to pain intensity, prescription for breakthrough pain) and indicators concerning patient-centred care (i.e., attention to psychological distress and educational needs) had very low compliance, highlighting specific quality gaps. A set of good practice indicators has been built and pilot tested as a feasible, reliable and useful quality monitoring tool, and underscoring particular and important areas for improvement. © 2014 European Pain Federation - EFIC®

  20. Multinomial-exponential reliability function: a software reliability model

    International Nuclear Information System (INIS)

    Saiz de Bustamante, Amalio; Saiz de Bustamante, Barbara

    2003-01-01

    The multinomial-exponential reliability function (MERF) was developed during a detailed study of the software failure/correction processes. Later on MERF was approximated by a much simpler exponential reliability function (EARF), which keeps most of MERF mathematical properties, so the two functions together makes up a single reliability model. The reliability model MERF/EARF considers the software failure process as a non-homogeneous Poisson process (NHPP), and the repair (correction) process, a multinomial distribution. The model supposes that both processes are statistically independent. The paper discusses the model's theoretical basis, its mathematical properties and its application to software reliability. Nevertheless it is foreseen model applications to inspection and maintenance of physical systems. The paper includes a complete numerical example of the model application to a software reliability analysis

  1. Reliability and Characterization of High Voltage Power Capacitors

    Science.gov (United States)

    2014-03-01

    in a Faraday cage to minimize external noise. In addition, electron microscopy could also be performed to identify the change in trap concentration...military bases in the United States. Energy product reliability affects the sustainability and cost- effectiveness of these systems, which must be tested...Energy product reliability affects the sustainability and cost- effectiveness of these systems, which must be tested by outside entities to ensure

  2. Mammographic casting-type calcification associated with small screen-detected invasive breast cancers: is this a reliable prognostic indicator?

    International Nuclear Information System (INIS)

    Peacock, C.; Given-Wilson, R.M.; Duffy, S.W.

    2004-01-01

    AIM: The aim of the present study was to establish whether mammographic casting-type calcification associated with small screen-detected invasive breast cancers is a reliable prognostic indicator. METHODS AND MATERIALS: We retrospectively identified 50 consecutive women diagnosed with an invasive cancer less than 15 mm who showed associated casting calcification on their screening mammograms. Controls were identified that showed no microcalcification and were matched for tumour size, histological type and lymph node status. A minimum of 5 years follow-up was obtained, noting recurrence and outcome. Conditional and unconditional logistic regression, depending on the outcome variable, were used to analyse the data, taking the matched design into account in both cases. Where small numbers prohibited the use of logistic regression, Fisher's exact test was used. RESULTS: Five deaths from breast cancer occurred out of the 50 cases, of which three were lymph node positive, two were lymph node negative and none were grade 3. None of the 78 control cases died from breast cancer. The difference in breast cancer death rates was significant by Fisher's exact test (p=0.02). Risk of recurrence was also significantly increased in the casting cases (OR=3.55, 95% CI 1.02-12.33, p=0.046). CONCLUSION: Although the overall outcome for small screen-detected breast cancers is good, our study suggests that casting calcification is a poorer prognostic factor. The advantage of a mammographic feature as an independent prognostic indicator lies in early identification of high-risk patients, allowing optimization of management

  3. Framework and indicator testing protocol for developing and piloting quality indicators for the UK quality and outcomes framework

    Directory of Open Access Journals (Sweden)

    Burke Martyn

    2011-08-01

    Full Text Available Abstract Background Quality measures should be subjected to a testing protocol before being used in practice using key attributes such as acceptability, feasibility and reliability, as well as identifying issues derived from actual implementation and unintended consequences. We describe the methodologies and results of an indicator testing protocol (ITP using data from proposed quality indicators for the United Kingdom Quality and Outcomes Framework (QOF. Methods The indicator testing protocol involved a multi-step and methodological process: 1 The RAND/UCLA Appropriateness Method, to test clarity and necessity, 2 data extraction from patients' medical records, to test technical feasibility and reliability, 3 diaries, to test workload, 4 cost-effectiveness modelling, and 5 semi-structured interviews, to test acceptability, implementation issues and unintended consequences. Testing was conducted in a sample of representative family practices in England. These methods were combined into an overall recommendation for each tested indicator. Results Using an indicator testing protocol as part of piloting was seen as a valuable way of testing potential indicators in 'real world' settings. Pilot 1 (October 2009-March 2010 involved thirteen indicators across six clinical domains and twelve indicators passed the indicator testing protocol. However, the indicator testing protocol identified a number of implementation issues and unintended consequences that can be rectified or removed prior to national roll out. A palliative care indicator is used as an exemplar of the value of piloting using a multiple attribute indicator testing protocol - while technically feasible and reliable, it was unacceptable to practice staff and raised concerns about potentially causing actual patient harm. Conclusions This indicator testing protocol is one example of a protocol that may be useful in assessing potential quality indicators when adapted to specific country health

  4. Histologic scoring indices for evaluation of disease activity in Crohn's disease.

    Science.gov (United States)

    Novak, Gregor; Parker, Claire E; Pai, Rish K; MacDonald, John K; Feagan, Brian G; Sandborn, William J; D'Haens, Geert; Jairath, Vipul; Khanna, Reena

    2017-07-21

    histological indices fulfilled the inclusion criteria.Inter-rater reliability was assessed in one study. For the Naini and Cortina Score, estimates of correlation were 'almost perfect', ranging from r = 0.94 to 0.96. The methodological quality of this study with respect to reliability was 'good'.With respect to validity, correlation estimates between various histological scoring systems and Crohn's disease activity as measured by objective markers of inflammation (including C-reactive protein, erythrocyte sedimentation rate, fecal calprotectin and fecal lactoferrin); endoscopic disease activity scores; clinical disease activity scores; and quality of life questionnaires were reported. Comparisons between histologic scoring indices and endoscopic scoring indices ranged from no correlation to 'substantial' (r = 0.779). The methodological quality of the studies that explored validity ranged form 'poor' to 'good'.Responsiveness data were available in seven studies. After subjects were administered a treatment of known efficacy, statistically significant change in the index score was demonstrated in five studies with respect to six indices. Two studies failed to indicate whether there was statistically significant change in the index score post-treatment. With regard to methodological quality, six of the studies were rated as 'poor' and one of the studies was rated as 'fair'.Feasibility was assessed by one study. The Naini and Cortina Score was shown to be simple to use and feasible for every given case. Currently there is no fully validated histological scoring index for evaluation of Crohn's disease activity. Development of a validated histological scoring index for Crohn's disease is a clinical and research priority.

  5. Sources of energy productivity change in China during 1997–2012: A decomposition analysis based on the Luenberger productivity indicator

    International Nuclear Information System (INIS)

    Wang, Ke; Wei, Yi-Ming

    2016-01-01

    Given that different energy inputs play different roles in production and that energy policy decision making requires an evaluation of productivity change in individual energy input to provide insight into the scope for improvement of the utilization of specific energy input, this study develops, based on the Luenberger productivity indicator and data envelopment analysis models, an aggregated specific energy productivity indicator combining the individual energy input productivity indicators that account for the contributions of each specific energy input toward energy productivity change. In addition, these indicators can be further decomposed into four factors: pure efficiency change, scale efficiency change, pure technology change, and scale of technology change. These decompositions enable a determination of which specific energy input is the driving force of energy productivity change and which of the four factors is the primary contributor of energy productivity change. An empirical analysis of China's energy productivity change over the period 1997–2012 indicates that (i) China's energy productivity growth may be overestimated if energy consumption structure is omitted; (ii) in regard to the contribution of specific energy input toward energy productivity growth, oil and electricity show positive contributions, but coal and natural gas show negative contributions; (iii) energy-specific productivity changes are mainly caused by technical changes rather than efficiency changes; and (iv) the Porter Hypothesis is partially supported in China that carbon emissions control regulations may lead to energy productivity growth. - Highlights: • An energy input specific Luenberger productivity indicator is proposed. • It enables to examine the contribution of specific energy input productivity change. • It can be decomposed for identifying pure and scale efficiency changes, as well as pure and scale technical changes. • China's energy productivity growth may

  6. reliability reliability

    African Journals Online (AJOL)

    eobe

    Corresponding author, Tel: +234-703. RELIABILITY .... V , , given by the code of practice. However, checks must .... an optimization procedure over the failure domain F corresponding .... of Concrete Members based on Utility Theory,. Technical ...

  7. Development and assessment of indices to determine stream fish vulnerability to climate change and habitat alteration

    Science.gov (United States)

    Sievert, Nicholas A.; Paukert, Craig P.; Tsang, Yin-Phan; Infante, Dana M.

    2016-01-01

    Understanding the future impacts of climate and land use change are critical for long-term biodiversity conservation. We developed and compared two indices to assess the vulnerability of stream fish in Missouri, USA based on species environmental tolerances, rarity, range size, dispersal ability and on the average connectivity of the streams occupied by each species. These two indices differed in how environmental tolerance was classified (i.e., vulnerability to habitat alteration, changes in stream temperature, and changes to flow regimes). Environmental tolerance was classified based on measured species responses to habitat alteration, and extremes in stream temperatures and flow conditions for one index, while environmental tolerance for the second index was based on species’ traits. The indices were compared to determine if vulnerability scores differed by index or state listing status. We also evaluated the spatial distribution of species classified as vulnerable to habitat alteration, changes in stream temperature, and change in flow regimes. Vulnerability scores were calculated for all 133 species with the trait association index, while only 101 species were evaluated using the species response index, because 32 species lacked data to analyze for a response. Scores from the trait association index were greater than the species response index. This is likely due to the species response index's inability to evaluate many rare species, which generally had high vulnerability scores for the trait association index. The indices were consistent in classifying vulnerability to habitat alteration, but varied in their classification of vulnerability due to increases in stream temperature and alterations to flow regimes, likely because extremes in current climate may not fully capture future conditions and their influence on stream fish communities. Both indices showed higher mean vulnerability scores for listed species than unlisted species, which provided a coarse

  8. Improving Power Converter Reliability

    DEFF Research Database (Denmark)

    Ghimire, Pramod; de Vega, Angel Ruiz; Beczkowski, Szymon

    2014-01-01

    of a high-power IGBT module during converter operation, which may play a vital role in improving the reliability of the power converters. The measured voltage is used to estimate the module average junction temperature of the high and low-voltage side of a half-bridge IGBT separately in every fundamental......The real-time junction temperature monitoring of a high-power insulated-gate bipolar transistor (IGBT) module is important to increase the overall reliability of power converters for industrial applications. This article proposes a new method to measure the on-state collector?emitter voltage...... is measured in a wind power converter at a low fundamental frequency. To illustrate more, the test method as well as the performance of the measurement circuit are also presented. This measurement is also useful to indicate failure mechanisms such as bond wire lift-off and solder layer degradation...

  9. Development of a Standard Set of Software Indicators for Aeronautical Systems Center.

    Science.gov (United States)

    1992-09-01

    29:12). The composite models listed include COCOMO and the Software Productivity, Quality, and Reliability Model ( SPQR ) (29:12). The SPQR model was...determine the values of the 68 input parameters. Source provides no specifics. Indicator Name SPQR (SW Productivity, Qual, Reliability) Indicator Class

  10. Measuring reliability under epistemic uncertainty: Review on non-probabilistic reliability metrics

    Directory of Open Access Journals (Sweden)

    Kang Rui

    2016-06-01

    Full Text Available In this paper, a systematic review of non-probabilistic reliability metrics is conducted to assist the selection of appropriate reliability metrics to model the influence of epistemic uncertainty. Five frequently used non-probabilistic reliability metrics are critically reviewed, i.e., evidence-theory-based reliability metrics, interval-analysis-based reliability metrics, fuzzy-interval-analysis-based reliability metrics, possibility-theory-based reliability metrics (posbist reliability and uncertainty-theory-based reliability metrics (belief reliability. It is pointed out that a qualified reliability metric that is able to consider the effect of epistemic uncertainty needs to (1 compensate the conservatism in the estimations of the component-level reliability metrics caused by epistemic uncertainty, and (2 satisfy the duality axiom, otherwise it might lead to paradoxical and confusing results in engineering applications. The five commonly used non-probabilistic reliability metrics are compared in terms of these two properties, and the comparison can serve as a basis for the selection of the appropriate reliability metrics.

  11. The reliability of commonly used electrophysiology measures.

    Science.gov (United States)

    Brown, K E; Lohse, K R; Mayer, I M S; Strigaro, G; Desikan, M; Casula, E P; Meunier, S; Popa, T; Lamy, J-C; Odish, O; Leavitt, B R; Durr, A; Roos, R A C; Tabrizi, S J; Rothwell, J C; Boyd, L A; Orth, M

    Electrophysiological measures can help understand brain function both in healthy individuals and in the context of a disease. Given the amount of information that can be extracted from these measures and their frequent use, it is essential to know more about their inherent reliability. To understand the reliability of electrophysiology measures in healthy individuals. We hypothesized that measures of threshold and latency would be the most reliable and least susceptible to methodological differences between study sites. Somatosensory evoked potentials from 112 control participants; long-latency reflexes, transcranial magnetic stimulation with resting and active motor thresholds, motor evoked potential latencies, input/output curves, and short-latency sensory afferent inhibition and facilitation from 84 controls were collected at 3 visits over 24 months at 4 Track-On HD study sites. Reliability was assessed using intra-class correlation coefficients for absolute agreement, and the effects of reliability on statistical power are demonstrated for different sample sizes and study designs. Measures quantifying latencies, thresholds, and evoked responses at high stimulator intensities had the highest reliability, and required the smallest sample sizes to adequately power a study. Very few between-site differences were detected. Reliability and susceptibility to between-site differences should be evaluated for electrophysiological measures before including them in study designs. Levels of reliability vary substantially across electrophysiological measures, though there are few between-site differences. To address this, reliability should be used in conjunction with theoretical calculations to inform sample size and ensure studies are adequately powered to detect true change in measures of interest. Copyright © 2017 Elsevier Inc. All rights reserved.

  12. Reliability evaluation of deregulated electric power systems for planning applications

    International Nuclear Information System (INIS)

    Ehsani, A.; Ranjbar, A.M.; Jafari, A.; Fotuhi-Firuzabad, M.

    2008-01-01

    In a deregulated electric power utility industry in which a competitive electricity market can influence system reliability, market risks cannot be ignored. This paper (1) proposes an analytical probabilistic model for reliability evaluation of competitive electricity markets and (2) develops a methodology for incorporating the market reliability problem into HLII reliability studies. A Markov state space diagram is employed to evaluate the market reliability. Since the market is a continuously operated system, the concept of absorbing states is applied to it in order to evaluate the reliability. The market states are identified by using market performance indices and the transition rates are calculated by using historical data. The key point in the proposed method is the concept that the reliability level of a restructured electric power system can be calculated using the availability of the composite power system (HLII) and the reliability of the electricity market. Two case studies are carried out over Roy Billinton Test System (RBTS) to illustrate interesting features of the proposed methodology

  13. Exploring changes in open defecation prevalence in sub-Saharan Africa based on national level indices.

    Science.gov (United States)

    Galan, Deise I; Kim, Seung-Sup; Graham, Jay P

    2013-05-30

    In sub-Saharan Africa, it is estimated that 215 million people continue to engage in open defecation. This practice facilitates the transmission of diarrheal diseases - one of the leading causes of mortality in children under 5 in sub-Saharan Africa. The main purpose of this study is to: estimate changes in open defecation prevalence between 2005 and 2010 across countries in sub-Saharan Africa; examine the association between national level indices and changes in open defecation prevalence; and assess how many countries can achieve 'open defecation free status' by 2015. After applying selection criteria, this study analyzed country-level data for 34 sub-Saharan African countries. Seven country-level indices were collected: 1) presence of a national sanitation policy; 2) budget line for sanitation; 3) budget allocated to sanitation; 4) annual per capita GDP; 5) GDP growth; 6) implementation of total sanitation approaches; and 7) per capita aid disbursement for water supply and sanitation. The relationships between these country-level indices and the change in open defecation from 2005 to 2010 were investigated using Wilcoxon Signed-Rank test and Spearman's rank correlation test. Only 3 countries (i.e. Ethiopia, Angola and Sao Tome and Principe) decreased open defecation by 10% or more between 2005 and 2010. No significant associations were observed between the change in open defecation prevalence and all of national level indices except per capita aid disbursement. Per capita aid disbursement for water and sanitation was positively associated with a reduction in open defecation (p-value = 0.02) for a subset of 29 low-income countries from 2005 to 2010. Only one country in our analysis, Angola, is on track to end open defecation by 2015 based on their performance between 2000 and 2010. Most of the national level indices, including a country's economic status, were not associated with the change in the open defecation prevalence. Based on current trends, the goal

  14. Indications of climatic change

    International Nuclear Information System (INIS)

    2005-04-01

    The earth's annual mean global temperature increased by around 0,6 C during the 20 century, with wide regional differences. Even if solar activity has played some part in the mean temperature rise and some greenhouse gases are present naturally in the atmosphere, enhancing of the greenhouse effect due to the human activities is responsible for a large and increasing part of the observed warming. The work of the Intergovernmental Panel on Climate Change confirms the future increase under all scenarios. Depending on the efforts made by mankind to limit greenhouse gases emissions, the global mean temperature in 2100 could be between 1,4 and 5,8 C higher than in 2000. (A.L.B.)

  15. Evaluation criteria of structural steel reliability

    International Nuclear Information System (INIS)

    Zav'yalov, A.S.

    1980-01-01

    Different low-carbon and medium-carbon structural steels are investigated. It is stated that steel reliability evaluation criteria depend on the fracture mode, steel suffering from the brittle fracture under the influence of the stresses (despite their great variety) arising in articles during the production and operation. Fibrous steel fracture at the given temperature and article thickness says about its high ductility and toughness and brittle fractures are impossible. Brittle fractures take place in case of a crystalline and mixed fracture with a predominant crystalline component. Evaluation methods of article and sample steel structural strength differing greatly from real articles in a thickness (diameter) or used at temperatures higher than possible operation temperatures cannot be reliability evaluation criteria because at a great thickness (diameter) and lower operation temperatures steel fracture and its strain mode can change resulting in a sharp reliability degradation

  16. Past and future changes in frost day indices on Catskill Mountain Region of New York

    Science.gov (United States)

    Changes in frost indices in the New York’s Catskill Mountains region, the location of water supply reservoirs for New York City, have potentially important implications. Frost day is defined as a day with Tmin < 0ºC. The objective of this study was to investigate past and predicted changes in minimu...

  17. Nuclear electric propulsion operational reliability and crew safety study

    International Nuclear Information System (INIS)

    Karns, J.J.; Fragola, J.R.; Kahan, L.; Pelaccio, D.

    1993-01-01

    The central purpose of this analysis is to assess the ''achievability'' of a nuclear electric propulsion (NEP) system in a given mission. ''Achievability'' is a concept introduced to indicate the extent to which a system that meets or achieves its design goals might be implemented using the existing technology base. In the context of this analysis, the objective is to assess the achievability of an NEP system for a manned Mars mission as it pertains to operational reliability and crew safety goals. By varying design parameters, then examining the resulting system achievability, the design and mission risk drivers can be identified. Additionally, conceptual changes in design approach or mission strategy which are likely to improve overall achievability of the NEP system can be examined

  18. Reliability Approach of a Compressor System using Reliability Block ...

    African Journals Online (AJOL)

    pc

    2018-03-05

    Mar 5, 2018 ... This paper presents a reliability analysis of such a system using reliability ... Keywords-compressor system, reliability, reliability block diagram, RBD .... the same structure has been kept with the three subsystems: air flow, oil flow and .... and Safety in Engineering Design", Springer, 2009. [3] P. O'Connor ...

  19. Reliability of Pressure Ulcer Rates: How Precisely Can We Differentiate Among Hospital Units, and Does the Standard Signal‐Noise Reliability Measure Reflect This Precision?

    Science.gov (United States)

    Cramer, Emily

    2016-01-01

    Abstract Hospital performance reports often include rankings of unit pressure ulcer rates. Differentiating among units on the basis of quality requires reliable measurement. Our objectives were to describe and apply methods for assessing reliability of hospital‐acquired pressure ulcer rates and evaluate a standard signal‐noise reliability measure as an indicator of precision of differentiation among units. Quarterly pressure ulcer data from 8,199 critical care, step‐down, medical, surgical, and medical‐surgical nursing units from 1,299 US hospitals were analyzed. Using beta‐binomial models, we estimated between‐unit variability (signal) and within‐unit variability (noise) in annual unit pressure ulcer rates. Signal‐noise reliability was computed as the ratio of between‐unit variability to the total of between‐ and within‐unit variability. To assess precision of differentiation among units based on ranked pressure ulcer rates, we simulated data to estimate the probabilities of a unit's observed pressure ulcer rate rank in a given sample falling within five and ten percentiles of its true rank, and the probabilities of units with ulcer rates in the highest quartile and highest decile being identified as such. We assessed the signal‐noise measure as an indicator of differentiation precision by computing its correlations with these probabilities. Pressure ulcer rates based on a single year of quarterly or weekly prevalence surveys were too susceptible to noise to allow for precise differentiation among units, and signal‐noise reliability was a poor indicator of precision of differentiation. To ensure precise differentiation on the basis of true differences, alternative methods of assessing reliability should be applied to measures purported to differentiate among providers or units based on quality. © 2016 The Authors. Research in Nursing & Health published by Wiley Periodicals, Inc. PMID:27223598

  20. Reliable control using the primary and dual Youla parameterizations

    DEFF Research Database (Denmark)

    Niemann, Hans Henrik; Stoustrup, J.

    2002-01-01

    Different aspects of modeling faults in dynamic systems are considered in connection with reliable control (RC). The fault models include models with additive faults, multiplicative faults and structural changes in the models due to faults in the systems. These descriptions are considered...... in connection with reliable control and feedback control with fault rejection. The main emphasis is on fault modeling. A number of fault diagnosis problems, reliable control problems, and feedback control with fault rejection problems are formulated/considered, again, mainly from a fault modeling point of view....... Reliability is introduced by means of the (primary) Youla parameterization of all stabilizing controllers, where an additional loop is closed around a diagnostic signal. In order to quantify the level of reliability, the dual Youla parameterization is introduced which can be used to analyze how large faults...

  1. Software reliability

    CERN Document Server

    Bendell, A

    1986-01-01

    Software Reliability reviews some fundamental issues of software reliability as well as the techniques, models, and metrics used to predict the reliability of software. Topics covered include fault avoidance, fault removal, and fault tolerance, along with statistical methods for the objective assessment of predictive accuracy. Development cost models and life-cycle cost models are also discussed. This book is divided into eight sections and begins with a chapter on adaptive modeling used to predict software reliability, followed by a discussion on failure rate in software reliability growth mo

  2. Validity and Reliability of Farsi Version of Youth Sport Environment Questionnaire

    Directory of Open Access Journals (Sweden)

    Mohammad Ali Eshghi

    2015-01-01

    Full Text Available The Youth Sport Environment Questionnaire (YSEQ had been developed from Group Environment Questionnaire, a well-known measure of team cohesion. The aim of this study was to adapt and examine the reliability and validity of the Farsi version of the YSEQ. This version was completed by 455 athletes aged 13–17 years. Results of confirmatory factor analysis indicated that two-factor solution showed a good fit to the data. The results also revealed that the Farsi YSEQ showed high internal consistency, test-retest reliability, and good concurrent validity. This study indicated that the Farsi version of the YSEQ is a valid and reliable measure to assess team cohesion in sport setting.

  3. Reliability of salivary testosterone measurements in diagnosis of Polycystic Ovarian Syndrome

    Directory of Open Access Journals (Sweden)

    Omnia Youssef

    2010-07-01

    Conclusion: Determination of salivary testosterone is a reliable method to detect changes in the concentration of available biologically active testosterone in the serum. Salivary testosterone provides a sensitive, simple, reliable, non-invasive and uncomplicated diagnostic approach for PCOS.

  4. Electrophoretic mobility shift in native gels indicates calcium-dependent structural changes of neuronal calcium sensor proteins.

    Science.gov (United States)

    Viviano, Jeffrey; Krishnan, Anuradha; Wu, Hao; Venkataraman, Venkat

    2016-02-01

    In proteins of the neuronal calcium sensor (NCS) family, changes in structure as well as function are brought about by the binding of calcium. In this article, we demonstrate that these structural changes, solely due to calcium binding, can be assessed through electrophoresis in native gels. The results demonstrate that the NCS proteins undergo ligand-dependent conformational changes that are detectable in native gels as a gradual decrease in mobility with increasing calcium but not other tested divalent cations such as magnesium, strontium, and barium. Surprisingly, such a gradual change over the entire tested range is exhibited only by the NCS proteins but not by other tested calcium-binding proteins such as calmodulin and S100B, indicating that the change in mobility may be linked to a unique NCS family feature--the calcium-myristoyl switch. Even within the NCS family, the changes in mobility are characteristic of the protein, indicating that the technique is sensitive to the individual features of the protein. Thus, electrophoretic mobility on native gels provides a simple and elegant method to investigate calcium (small ligand)-induced structural changes at least in the superfamily of NCS proteins. Copyright © 2015 Elsevier Inc. All rights reserved.

  5. Evaluating North American Electric Grid Reliability Using the Barabasi-Albert Network Model

    OpenAIRE

    Chassin, David P.; Posse, Christian

    2004-01-01

    The reliability of electric transmission systems is examined using a scale-free model of network structure and failure propagation. The topologies of the North American eastern and western electric networks are analyzed to estimate their reliability based on the Barabasi-Albert network model. A commonly used power system reliability index is computed using a simple failure propagation model. The results are compared to the values of power system reliability indices previously obtained using s...

  6. New Endoscopic Indicator of Esophageal Achalasia: “Pinstripe Pattern”

    Science.gov (United States)

    Minami, Hitomi; Isomoto, Hajime; Miuma, Satoshi; Kobayashi, Yasutoshi; Yamaguchi, Naoyuki; Urabe, Shigetoshi; Matsushima, Kayoko; Akazawa, Yuko; Ohnita, Ken; Takeshima, Fuminao; Inoue, Haruhiro; Nakao, Kazuhiko

    2015-01-01

    Background and Study Aims Endoscopic diagnosis of esophageal achalasia lacking typical endoscopic features can be extremely difficult. The aim of this study was to identify simple and reliable early indicator of esophageal achalasia. Patients and Methods This single-center retrospective study included 56 cases of esophageal achalasia without previous treatment. As a control, 60 non-achalasia subjects including reflux esophagitis and superficial esophageal cancer were also included in this study. Endoscopic findings were evaluated according to Descriptive Rules for Achalasia of the Esophagus as follows: (1) esophageal dilatation, (2) abnormal retention of liquid and/or food, (3) whitish change of the mucosal surface, (4) functional stenosis of the esophago-gastric junction, and (5) abnormal contraction. Additionally, the presence of the longitudinal superficial wrinkles of esophageal mucosa, “pinstripe pattern (PSP)” was evaluated endoscopically. Then, inter-observer diagnostic agreement was assessed for each finding. Results The prevalence rates of the above-mentioned findings (1–5) were 41.1%, 41.1%, 16.1%, 94.6%, and 43.9%, respectively. PSP was observed in 60.7% of achalasia, while none of the control showed positivity for PSP. PSP was observed in 26 (62.5%) of 35 cases with shorter history achalasia were 83.8%, 64.7%, and 100%, respectively. Conclusion “Pinstripe pattern” could be a reliable indicator for early discrimination of primary esophageal achalasia. PMID:25664812

  7. System Reliability Engineering

    International Nuclear Information System (INIS)

    Lim, Tae Jin

    2005-02-01

    This book tells of reliability engineering, which includes quality and reliability, reliability data, importance of reliability engineering, reliability and measure, the poisson process like goodness of fit test and the poisson arrival model, reliability estimation like exponential distribution, reliability of systems, availability, preventive maintenance such as replacement policies, minimal repair policy, shock models, spares, group maintenance and periodic inspection, analysis of common cause failure, and analysis model of repair effect.

  8. Power system reliability memento; Memento de la surete du systeme electrique

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2002-07-01

    The reliability memento of the French power system (national power transmission grid) is an educational document which purpose is to point out the role of each one as regards power system operating reliability. This memento was first published in 1999. Extensive changes have taken place since then. The new 2002 edition shows that system operating reliability is as an important subject as ever: 1 - foreword; 2 - system reliability: the basics; 3 - equipment measures taken in order to guarantee the reliability of the system; 4 - organisational and human measures taken to guarantee the reliability of the system; appendix 1 - system operation: basic concepts; appendix 2 - guiding principles governing the reliability of the power system; appendix 3 - international associations of transmission system operators; appendix 4 - description of major incidents.

  9. Accident Sequence Evaluation Program: Human reliability analysis procedure

    Energy Technology Data Exchange (ETDEWEB)

    Swain, A.D.

    1987-02-01

    This document presents a shortened version of the procedure, models, and data for human reliability analysis (HRA) which are presented in the Handbook of Human Reliability Analysis With emphasis on Nuclear Power Plant Applications (NUREG/CR-1278, August 1983). This shortened version was prepared and tried out as part of the Accident Sequence Evaluation Program (ASEP) funded by the US Nuclear Regulatory Commission and managed by Sandia National Laboratories. The intent of this new HRA procedure, called the ''ASEP HRA Procedure,'' is to enable systems analysts, with minimal support from experts in human reliability analysis, to make estimates of human error probabilities and other human performance characteristics which are sufficiently accurate for many probabilistic risk assessments. The ASEP HRA Procedure consists of a Pre-Accident Screening HRA, a Pre-Accident Nominal HRA, a Post-Accident Screening HRA, and a Post-Accident Nominal HRA. The procedure in this document includes changes made after tryout and evaluation of the procedure in four nuclear power plants by four different systems analysts and related personnel, including human reliability specialists. The changes consist of some additional explanatory material (including examples), and more detailed definitions of some of the terms. 42 refs.

  10. A reliability simulation language for reliability analysis

    International Nuclear Information System (INIS)

    Deans, N.D.; Miller, A.J.; Mann, D.P.

    1986-01-01

    The results of work being undertaken to develop a Reliability Description Language (RDL) which will enable reliability analysts to describe complex reliability problems in a simple, clear and unambiguous way are described. Component and system features can be stated in a formal manner and subsequently used, along with control statements to form a structured program. The program can be compiled and executed on a general-purpose computer or special-purpose simulator. (DG)

  11. Improvement of the reliability graph with general gates to analyze the reliability of dynamic systems that have various operation modes

    Energy Technology Data Exchange (ETDEWEB)

    Shin, Seung Ki [Div. of Research Reactor System Design, Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of); No, Young Gyu; Seong, Poong Hyun [Dept. of Nuclear and Quantum Engineering, Korea Advanced Institute of Science and Technology, Daejeon (Korea, Republic of)

    2016-04-15

    The safety of nuclear power plants is analyzed by a probabilistic risk assessment, and the fault tree analysis is the most widely used method for a risk assessment with the event tree analysis. One of the well-known disadvantages of the fault tree is that drawing a fault tree for a complex system is a very cumbersome task. Thus, several graphical modeling methods have been proposed for the convenient and intuitive modeling of complex systems. In this paper, the reliability graph with general gates (RGGG) method, one of the intuitive graphical modeling methods based on Bayesian networks, is improved for the reliability analyses of dynamic systems that have various operation modes with time. A reliability matrix is proposed and it is explained how to utilize the reliability matrix in the RGGG for various cases of operation mode changes. The proposed RGGG with a reliability matrix provides a convenient and intuitive modeling of various operation modes of complex systems, and can also be utilized with dynamic nodes that analyze the failure sequences of subcomponents. The combinatorial use of a reliability matrix with dynamic nodes is illustrated through an application to a shutdown cooling system in a nuclear power plant.

  12. Improvement of the reliability graph with general gates to analyze the reliability of dynamic systems that have various operation modes

    International Nuclear Information System (INIS)

    Shin, Seung Ki; No, Young Gyu; Seong, Poong Hyun

    2016-01-01

    The safety of nuclear power plants is analyzed by a probabilistic risk assessment, and the fault tree analysis is the most widely used method for a risk assessment with the event tree analysis. One of the well-known disadvantages of the fault tree is that drawing a fault tree for a complex system is a very cumbersome task. Thus, several graphical modeling methods have been proposed for the convenient and intuitive modeling of complex systems. In this paper, the reliability graph with general gates (RGGG) method, one of the intuitive graphical modeling methods based on Bayesian networks, is improved for the reliability analyses of dynamic systems that have various operation modes with time. A reliability matrix is proposed and it is explained how to utilize the reliability matrix in the RGGG for various cases of operation mode changes. The proposed RGGG with a reliability matrix provides a convenient and intuitive modeling of various operation modes of complex systems, and can also be utilized with dynamic nodes that analyze the failure sequences of subcomponents. The combinatorial use of a reliability matrix with dynamic nodes is illustrated through an application to a shutdown cooling system in a nuclear power plant

  13. Human reliability

    International Nuclear Information System (INIS)

    Embrey, D.E.

    1987-01-01

    Concepts and techniques of human reliability have been developed and are used mostly in probabilistic risk assessment. For this, the major application of human reliability assessment has been to identify the human errors which have a significant effect on the overall safety of the system and to quantify the probability of their occurrence. Some of the major issues within human reliability studies are reviewed and it is shown how these are applied to the assessment of human failures in systems. This is done under the following headings; models of human performance used in human reliability assessment, the nature of human error, classification of errors in man-machine systems, practical aspects, human reliability modelling in complex situations, quantification and examination of human reliability, judgement based approaches, holistic techniques and decision analytic approaches. (UK)

  14. Relevance of the study premises in the reliability indexes; Relevancia das premissas de estudo nos indices de confiabilidade

    Energy Technology Data Exchange (ETDEWEB)

    Camara Neto, Felipe [Furnas Centrais Eletricas S.A, Rio de Janeiro, RJ (Brazil)], email: fcamara@furnas.com.br; Schilling, Marcus Th. [Universidade Federal Fluminense (UFF) Niteroi, RJ (Brazil). Dept. de Engenharia Eletrica], E-mail: schilling@ic.uff.br; Silva, Armando M. Leite da [Universidade Federal de Itajuba (UNIFEI), MG (Brazil). Inst. de Sistemas Eletricos e Energia], E-mail: armando@unifei.edu.br

    2009-07-01

    This article gives subsidies for overcoming the difficulties for the conceptual interpretation of the reliability indexes coming from the probabilistic analysis typical of power systems adequacy. Firstly, it is listed a set of factors that contribute to the generation of significant statistic amplitudes of numerical values. After this, a referential paradigm is obtained for the Brazilian test-system of 107 bars, according to the used methodology in various companies in Brazil. Taking as reference the obtained pattern, a set of experiments is done, and it is obtained the variation range of the severity index, and a set of another traditional indexes in the reliability analysis.

  15. Bringing indices of species vulnerability to climate change into geographic space: an assessment across the Coronado national forest

    Science.gov (United States)

    Jennifer E. Davison; Sharon Coe; Deborah Finch; Erika Rowland; Megan Friggens; Lisa J. Graumlich

    2012-01-01

    Indices that rate the vulnerability of species to climate change in a given area are increasingly used to inform conservation and climate change adaptation strategies. These species vulnerability indices (SVI) are not commonly associated with landscape features that may affect local-scale vulnerability. To do so would increase their utility by allowing managers to...

  16. Dimensional indicators of generalized anxiety disorder severity for DSM-V.

    Science.gov (United States)

    Niles, Andrea N; Lebeau, Richard T; Liao, Betty; Glenn, Daniel E; Craske, Michelle G

    2012-03-01

    For DSM-V, simple dimensional measures of disorder severity will accompany diagnostic criteria. The current studies examine convergent validity and test-retest reliability of two potential dimensional indicators of worry severity for generalized anxiety disorder (GAD): percent of the day worried and number of worry domains. In study 1, archival data from diagnostic interviews from a community sample of individuals diagnosed with one or more anxiety disorders (n = 233) were used to assess correlations between percent of the day worried and number of worry domains with other measures of worry severity (clinical severity rating (CSR), age of onset, number of comorbid disorders, Penn state worry questionnaire (PSWQ)) and DSM-IV criteria (excessiveness, uncontrollability and number of physical symptoms). Both measures were significantly correlated with CSR and number of comorbid disorders, and with all three DSM-IV criteria. In study 2, test-retest reliability of percent of the day worried and number of worry domains were compared to test-retest reliability of DSM-IV diagnostic criteria in a non-clinical sample of undergraduate students (n = 97) at a large west coast university. All measures had low test-retest reliability except percent of the day worried, which had moderate test-retest reliability. Findings suggest that these two indicators capture worry severity, and percent of the day worried may be the most reliable existing indicator. These measures may be useful as dimensional measures for DSM-V. Copyright © 2012 Elsevier Ltd. All rights reserved.

  17. Changes of visual-field global indices after cataract surgery in primary open-angle glaucoma patients.

    Science.gov (United States)

    Seol, Bo Ram; Jeoung, Jin Wook; Park, Ki Ho

    2016-11-01

    To determine changes of visual-field (VF) global indices after cataract surgery and the factors associated with the effect of cataracts on those indices in primary open-angle glaucoma (POAG) patients. A retrospective chart review of 60 POAG patients who had undergone phacoemulsification and intraocular lens insertion was conducted. All of the patients were evaluated with standard automated perimetry (SAP; 30-2 Swedish interactive threshold algorithm; Carl Zeiss Meditec Inc.) before and after surgery. VF global indices before surgery were compared with those after surgery. The best-corrected visual acuity, intraocular pressure (IOP), number of glaucoma medications before surgery, mean total deviation (TD) values, mean pattern deviation (PD) value, and mean TD-PD value were also compared with the corresponding postoperative values. Additionally, postoperative peak IOP and mean IOP were evaluated. Univariate and multivariate logistic regression analyses were performed to identify the factors associated with the effect of cataract on global indices. Mean deviation (MD) after cataract surgery was significantly improved compared with the preoperative MD. Pattern standard deviation (PSD) and visual-field index (VFI) after surgery were similar to those before surgery. Also, mean TD and mean TD-PD were significantly improved after surgery. The posterior subcapsular cataract (PSC) type showed greater MD changes than did the non-PSC type in both the univariate and multivariate logistic regression analyses. In the univariate logistic regression analysis, the preoperative TD-PD value and type of cataract were associated with MD change. However, in the multivariate logistic regression analysis, type of cataract was the only associated factor. None of the other factors was associated with MD change. MD was significantly affected by cataracts, whereas PSD and VFI were not. Most notably, the PSC type showed better MD improvement compared with the non-PSC type after cataract surgery

  18. Validity and Reliability of a Medicine Ball Explosive Power Test.

    Science.gov (United States)

    Stockbrugger, Barry A.; Haennel, Robert G.

    2001-01-01

    Evaluated the validity and reliability of a medicine ball throw test to evaluate explosive power. Data on competitive sand volleyball players who performed a medicine ball throw and a standard countermovement jump indicated that the medicine ball throw test was a valid and reliable way to assess explosive power for an analogous total-body movement…

  19. Reliability Modeling of Electromechanical System with Meta-Action Chain Methodology

    Directory of Open Access Journals (Sweden)

    Genbao Zhang

    2018-01-01

    Full Text Available To establish a more flexible and accurate reliability model, the reliability modeling and solving algorithm based on the meta-action chain thought are used in this thesis. Instead of estimating the reliability of the whole system only in the standard operating mode, this dissertation adopts the structure chain and the operating action chain for the system reliability modeling. The failure information and structure information for each component are integrated into the model to overcome the given factors applied in the traditional modeling. In the industrial application, there may be different operating modes for a multicomponent system. The meta-action chain methodology can estimate the system reliability under different operating modes by modeling the components with varieties of failure sensitivities. This approach has been identified by computing some electromechanical system cases. The results indicate that the process could improve the system reliability estimation. It is an effective tool to solve the reliability estimation problem in the system under various operating modes.

  20. The impact of intrinsic motivation on session attendance and reliable cognitive improvement in cognitive remediation in schizophrenia.

    Science.gov (United States)

    Bryce, S D; Lee, S J; Ponsford, J L; Lawrence, R J; Tan, E J; Rossell, S L

    2018-06-20

    Cognitive remediation (CR) is considered a potentially effective method of improving cognitive function in people with schizophrenia. Few studies, however, have explored the role of intrinsic motivation on treatment utilization or training outcomes in CR in this population. This study explored the impact of task-specific intrinsic motivation on attendance and reliable cognitive improvement in a controlled trial comparing CR with a computer game (CG) playing control. Forty-nine participants with schizophrenia or schizoaffective disorder, allocated to 10 weeks of group-based CR (n = 25) or CG control (n = 24), provided complete outcome data at baseline. Forty-three participants completed their assigned intervention. Cognition, psychopathology and intrinsic motivation were measured at baseline and end-treatment. Regression analyses explored the relative contribution of baseline motivation and other clinical factors to session attendance as well as the association of baseline and change in intrinsic motivation with the odds of reliable cognitive improvement (calculated using reliable change indices). Baseline reports of perceived program value were the only significant multivariable predictor of session attendance when including global cognition and psychiatric symptomatology. The odds of reliable cognitive improvement significantly increased with greater improvements in program interest and value from baseline to end-treatment. Motivational changes over time were highly variable between participants. Task-specific intrinsic motivation in schizophrenia may represent an important patient-related factor that contributes to session attendance and cognitive improvements in CR. Regular evaluation and enhancement of intrinsic motivation in cognitively enhancing interventions may optimize treatment engagement and the likelihood of meaningful training outcomes. Copyright © 2018 Elsevier B.V. All rights reserved.

  1. Validity and Reliability of Baseline Testing in a Standardized Environment.

    Science.gov (United States)

    Higgins, Kathryn L; Caze, Todd; Maerlender, Arthur

    2017-08-11

    The Immediate Postconcussion Assessment and Cognitive Testing (ImPACT) is a computerized neuropsychological test battery commonly used to determine cognitive recovery from concussion based on comparing post-injury scores to baseline scores. This model is based on the premise that ImPACT baseline test scores are a valid and reliable measure of optimal cognitive function at baseline. Growing evidence suggests that this premise may not be accurate and a large contributor to invalid and unreliable baseline test scores may be the protocol and environment in which baseline tests are administered. This study examined the effects of a standardized environment and administration protocol on the reliability and performance validity of athletes' baseline test scores on ImPACT by comparing scores obtained in two different group-testing settings. Three hundred-sixty one Division 1 cohort-matched collegiate athletes' baseline data were assessed using a variety of indicators of potential performance invalidity; internal reliability was also examined. Thirty-one to thirty-nine percent of the baseline cases had at least one indicator of low performance validity, but there were no significant differences in validity indicators based on environment in which the testing was conducted. Internal consistency reliability scores were in the acceptable to good range, with no significant differences between administration conditions. These results suggest that athletes may be reliably performing at levels lower than their best effort would produce. © The Author 2017. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  2. Reliability Calculations

    DEFF Research Database (Denmark)

    Petersen, Kurt Erling

    1986-01-01

    Risk and reliability analysis is increasingly being used in evaluations of plant safety and plant reliability. The analysis can be performed either during the design process or during the operation time, with the purpose to improve the safety or the reliability. Due to plant complexity and safety...... and availability requirements, sophisticated tools, which are flexible and efficient, are needed. Such tools have been developed in the last 20 years and they have to be continuously refined to meet the growing requirements. Two different areas of application were analysed. In structural reliability probabilistic...... approaches have been introduced in some cases for the calculation of the reliability of structures or components. A new computer program has been developed based upon numerical integration in several variables. In systems reliability Monte Carlo simulation programs are used especially in analysis of very...

  3. ANALYSIS OF RELIABILITY OF NONRECTORABLE REDUNDANT POWER SYSTEMS TAKING INTO ACCOUNT COMMON FAILURES

    Directory of Open Access Journals (Sweden)

    V. A. Anischenko

    2014-01-01

    Full Text Available Reliability Analysis of nonrestorable redundant power Systems of industrial plants and other consumers of electric energy was carried out. The main attention was paid to numbers failures influence, caused by failures of all elements of System due to one general reason. Noted the main possible reasons of common failures formation. Two main indicators of reliability of non-restorable systems are considered: average time of no-failure operation and mean probability of no-failure operation. Modeling of failures were carried out by mean of division of investigated system into two in-series connected subsystems, one of them indicated independent failures, but the other indicated common failures. Due to joined modeling of single and common failures resulting intensity of failures is the amount incompatible components: intensity statistically independent failures and intensity of common failures of elements and system in total.It is shown the influence of common failures of elements on average time of no-failure operation of system. There is built the scale of preference of systems according to criterion of  average time maximum of no-failure operation, depending on portion of common failures. It is noticed that such common failures don’t influence on the scale of preference, but  change intervals of time, determining the moments of systems failures and excepting them from the number of comparators. There were discussed two problems  of conditionally optimization of  systems’  reservation choice, taking into account their reliability and cost. The first problem is solved due to criterion of minimum cost of system providing mean probability of no-failure operation, the second problem is solved due to criterion of maximum of mean probability of no-failure operation with cost limitation of system.

  4. Neutron logging reliability techniques and apparatus

    International Nuclear Information System (INIS)

    Johnstone, C.W.

    1978-01-01

    This invention relates in general to neutron logging of earth formations, and in particular, to novel apparatus and procedures for determining the validity, or reliability, of data derived at least in part by logging neutron characteristics of earth formations and, if desired, for affording verifiably accurate indications of such data

  5. Neutron logging reliability techniques and apparatus

    International Nuclear Information System (INIS)

    Johnstone, C.W.

    1974-01-01

    This invention relates in general to neutron logging of earth formations, and in particular, to novel apparatus and procedures for determining the validity, or reliability, of data derived at least in part by logging neutron characteristics of earth formations and, if desired, for affording verifiably accurate indications of such data. (author)

  6. Outcome indicators for the evaluation of energy policy instruments and technical change

    International Nuclear Information System (INIS)

    Neij, Lena; Astrand, Kerstin

    2006-01-01

    The aim of this paper is to propose a framework for the evaluation of policy instruments designed to affect development and dissemination of new energy technologies. The evaluation approach is based on the analysis of selected outcome indicators describing the process of technical change, i.e. the development and dissemination of new energy technologies, on the basis of a socio-technical systems approach. The outcome indicators are used to analyse the effect, in terms of outcome, and outcome scope of the policy instruments as well as the extent to which the policy instruments support diversity, learning and institutional change. The analysis of two cases of evaluations, of energy efficiency policy and wind energy policy in Sweden, shows that the approach has several advantages, allowing continuous evaluation and providing important information for the redesign of policy instruments. There are also disadvantages associated with the approach, such as complexity, possible high cost and the requirement of qualified evaluators. Nevertheless, it is concluded that the information on the continuous performance of different policy instruments and their effects on the introduction and dissemination of new energy technologies, provided by this evaluation approach, is essential for an improved adaptation and implementation of energy and climate policy

  7. Night-to-night arousal variability and interscorer reliability of arousal measurements.

    Science.gov (United States)

    Loredo, J S; Clausen, J L; Ancoli-Israel, S; Dimsdale, J E

    1999-11-01

    Measurement of arousals from sleep is clinically important, however, their definition is not well standardized, and little data exist on reliability. The purpose of this study is to determine factors that affect arousal scoring reliability and night-to-night arousal variability. The night-to-night arousal variability and interscorer reliability was assessed in 20 subjects with and without obstructive sleep apnea undergoing attended polysomnography during two consecutive nights. Five definitions of arousal were studied, assessing duration of electroencephalographic (EEG) frequency changes, increases in electromyographic (EMG) activity and leg movement, association with respiratory events, as well as the American Sleep Disorders Association (ASDA) definition of arousals. NA. NA. NA. Interscorer reliability varied with the definition of arousal and ranged from an Intraclass correlation (ICC) of 0.19 to 0.92. Arousals that included increases in EMG activity or leg movement had the greatest reliability, especially when associated with respiratory events (ICC 0.76 to 0.92). The ASDA arousal definition had high interscorer reliability (ICC 0.84). Reliability was lowest for arousals consisting of EEG changes lasting <3 seconds (ICC 0.19 to 0.37). The within subjects night-to-night arousal variability was low for all arousal definitions In a heterogeneous population, interscorer arousal reliability is enhanced by increases in EMG activity, leg movements, and respiratory events and decreased by short duration EEG arousals. The arousal index night-to-night variability was low for all definitions.

  8. Reliability in the utility computing era: Towards reliable Fog computing

    DEFF Research Database (Denmark)

    Madsen, Henrik; Burtschy, Bernard; Albeanu, G.

    2013-01-01

    This paper considers current paradigms in computing and outlines the most important aspects concerning their reliability. The Fog computing paradigm as a non-trivial extension of the Cloud is considered and the reliability of the networks of smart devices are discussed. Combining the reliability...... requirements of grid and cloud paradigms with the reliability requirements of networks of sensor and actuators it follows that designing a reliable Fog computing platform is feasible....

  9. The Americleft Speech Project: A Training and Reliability Study.

    Science.gov (United States)

    Chapman, Kathy L; Baylis, Adriane; Trost-Cardamone, Judith; Cordero, Kelly Nett; Dixon, Angela; Dobbelsteyn, Cindy; Thurmes, Anna; Wilson, Kristina; Harding-Bell, Anne; Sweeney, Triona; Stoddard, Gregory; Sell, Debbie

    2016-01-01

    To describe the results of two reliability studies and to assess the effect of training on interrater reliability scores. The first study (1) examined interrater and intrarater reliability scores (weighted and unweighted kappas) and (2) compared interrater reliability scores before and after training on the use of the Cleft Audit Protocol for Speech-Augmented (CAPS-A) with British English-speaking children. The second study examined interrater and intrarater reliability on a modified version of the CAPS-A (CAPS-A Americleft Modification) with American and Canadian English-speaking children. Finally, comparisons were made between the interrater and intrarater reliability scores obtained for Study 1 and Study 2. The participants were speech-language pathologists from the Americleft Speech Project. In Study 1, interrater reliability scores improved for 6 of the 13 parameters following training on the CAPS-A protocol. Comparison of the reliability results for the two studies indicated lower scores for Study 2 compared with Study 1. However, this appeared to be an artifact of the kappa statistic that occurred due to insufficient variability in the reliability samples for Study 2. When percent agreement scores were also calculated, the ratings appeared similar across Study 1 and Study 2. The findings of this study suggested that improvements in interrater reliability could be obtained following a program of systematic training. However, improvements were not uniform across all parameters. Acceptable levels of reliability were achieved for those parameters most important for evaluation of velopharyngeal function.

  10. Dependent systems reliability estimation by structural reliability approach

    DEFF Research Database (Denmark)

    Kostandyan, Erik; Sørensen, John Dalsgaard

    2014-01-01

    Estimation of system reliability by classical system reliability methods generally assumes that the components are statistically independent, thus limiting its applicability in many practical situations. A method is proposed for estimation of the system reliability with dependent components, where...... the leading failure mechanism(s) is described by physics of failure model(s). The proposed method is based on structural reliability techniques and accounts for both statistical and failure effect correlations. It is assumed that failure of any component is due to increasing damage (fatigue phenomena...... identification. Application of the proposed method can be found in many real world systems....

  11. SOILS AS INDICATORS OF CLIMATIC CHANGES

    Directory of Open Access Journals (Sweden)

    Yury Chendev

    2012-01-01

    Full Text Available A number of examples for the reaction of chernozems in the center of the East European Plain and their relation to different periodical climatic changes are examined. According to unequal-age chernozems properties, the transition from the Middle Holocene arid conditions to the Late Holocene wet conditions occurred at 4000 yr BP. Using data on changes of soil properties, the position of boundary between steppe and forest-steppe and the annual amount of precipitation at approximately 4000 yr BP were reconstructed. The change from warm-dry to cool-moist climatic phases, which occurred at the end of the XX century as a reflection of intra-age-long climatic cyclic recurrence, led to the strengthening of dehumification over the profile of automorphic chernozems and to the reduction of its content in the upper meter of the soils. The leaching of carbonates and of readily soluble salts contributed to the decrease in soil areas occupied by typical and solonetzic chernozems, and to the increase in areas occupied by leached chernozems.

  12. Test-retest reliability and factor structures of organizational citizenship behavior for Hong Kong workers.

    Science.gov (United States)

    Lam, S S

    2001-02-01

    In 1990 Podsakoff, MacKenzie, Moorman, and Fetter developed a scale to measure the five dimensions of organizational citizenship behavior. Test-retest data over 15 weeks are reported for this scale for a sample of 82 female and 32 male Chinese tellers (ages 18 to 54 years) from a large international bank in Hong Kong. Stability was .83, and there was no significant change between Times 1 and 2. Analysis indicated the five-factor structure and showed it to be a reliable measure when used with a nonwestern sample.

  13. Canadian environmental sustainability indicators: highlights 2005

    International Nuclear Information System (INIS)

    2005-12-01

    Canadians' health and their social and economic well-being are fundamentally linked to the quality of their environment. Recognizing this, in 2004 the Government of Canada committed to establishing national indicators of freshwater quality, air quality and greenhouse gas emissions. The goal of these new indicators is to provide Canadians with more regular and reliable information on the state of their environment and how it is linked with human activity. Canadians need clearly defined environmental indicators - measuring sticks that can track the results that have been achieved through the efforts of governments, industries and individuals to protect and improve the environment. Environment Canada, Statistics Canada and Health Canada are working together to further develop and communicate these indicators. Reflecting the joint responsibility for environmental management in Canada, this effort has benefited from the cooperation and input of the provinces and territories. The indicators are: air quality; greenhouse gas emissions; and, freshwater quality. Air quality tracks Canadians' exposure to ground-level ozone - a key component of smog. The indicator measures one of the most common, harmful air pollutants to which people are exposed. The use of the seasonal average of ozone concentrations reflects the potential for long-term health effects. Greenhouse gas emissions tracks the annual releases of the six greenhouse gases that are the major contributors to climate change. The indicator comes directly from the greenhouse gas inventory report prepared by Environment Canada for the United Nations Framework Convention on Climate Change (UNFCCC) and the Kyoto Protocol. The data are widely used to report on progress toward Canada's Kyoto target for reduced emissions. Freshwater quality reports the status of surface water quality at selected monitoring sites across the country. For this first report, the focus of the indicator is on the protection of aquatic life, such as

  14. The test-retest reliability of the latent construct of executive function depends on whether tasks are represented as formative or reflective indicators.

    Science.gov (United States)

    Willoughby, Michael T; Kuhn, Laura J; Blair, Clancy B; Samek, Anya; List, John A

    2017-10-01

    This study investigates the test-retest reliability of a battery of executive function (EF) tasks with a specific interest in testing whether the method that is used to create a battery-wide score would result in differences in the apparent test-retest reliability of children's performance. A total of 188 4-year-olds completed a battery of computerized EF tasks twice across a period of approximately two weeks. Two different approaches were used to create a score that indexed children's overall performance on the battery-i.e., (1) the mean score of all completed tasks and (2) a factor score estimate which used confirmatory factor analysis (CFA). Pearson and intra-class correlations were used to investigate the test-retest reliability of individual EF tasks, as well as an overall battery score. Consistent with previous studies, the test-retest reliability of individual tasks was modest (rs ≈ .60). The test-retest reliability of the overall battery scores differed depending on the scoring approach (r mean  = .72; r factor_ score  = .99). It is concluded that the children's performance on individual EF tasks exhibit modest levels of test-retest reliability. This underscores the importance of administering multiple tasks and aggregating performance across these tasks in order to improve precision of measurement. However, the specific strategy that is used has a large impact on the apparent test-retest reliability of the overall score. These results replicate our earlier findings and provide additional cautionary evidence against the routine use of factor analytic approaches for representing individual performance across a battery of EF tasks.

  15. Changes in EEG indices and serotonin concentrations in depression and anxiety disorders

    Directory of Open Access Journals (Sweden)

    I. V. Kichuk

    2016-01-01

    Full Text Available Electroencephalogram (EEG is an important tool to study brain function. EEG can evaluate the current functional state of the brain with high temporal resolution and identify metabolic and ion disorders that cannot be detected by magnetic resonance imaging.Objective: to analyze the relationship between some neurophysiological and biochemical parameters with a Neuro-KM hardware-software complex for the topographic mapping of brain electrical activity.Patients and methods. 75 patients with depression, 101 with anxiety disorders (AD, and 86 control individuals were examined. EEG spectrum and coherence changes were estimated in the depression and AD groups versus the control group. Correlation analysis of EEG indices and blood serotonin concentrations was carried out.Results and discussion. The patients with depression and those with AD as compared to the controls were observed to have similar EEG spectral changes in the beta band. Coherence analysis in the beta-band showed that both disease groups versus the control group had oppositely directed changes: a reduction in intra- and interhemispheric coherence for depression and its increase for AD (p < 0.001. That in the theta and alpha bands revealed that both disease groups had unidirectional interhemispheric coherence changes: a decrease in integration in the alpha band and its increase in the theta and delta bands in the depression and AD groups (p < 0.05 and multidirectional changes in intrahemispheric coherence: its reduction in the depression group and an increase in the AD group (p < 0.05. Correlation analysis of EEG parameters and platelet serotonin concentrations showed opposite correlations of serotonin concentrations and EEG percentage power in the theta and beta bands. When there were higher serotonin concentrations in the patients with depression, EEG demonstrated a preponderance of a synchronization pattern; when these were in the patients with AD, there was a predominance

  16. Evaluating multiple indices of agricultural water use efficiency and productivity to improve comparisons between sites and trends

    Science.gov (United States)

    Levy, M. C.

    2012-12-01

    Approximately 70% of global available freshwater supplies are used in the agricultural sector. Increased demands for water to meet growing population food requirements, and expected changes in the reliability of freshwater supplies due to climate change, threaten the sustainability of water supplies worldwide - not only on farms, but in connected cities and industries. Researchers concerned with agricultural water use sustainability use a variety of theoretical and empirical measures of efficiency and productivity to gain insight into the sustainability of agricultural water use. However, definitions of measures, or indices, vary between different natural and political boundaries, across regions, states and nations and between their respective research, industry, and environmental groups. Index development responds to local data availability and local agendas, and there is debate about the validity of various indices. However, real differences in empirical index measures are not well-understood across the multiple disciplines that study agricultural water use, including engineering and hydrology, agronomy, climate and soil sciences, and economics. Nevertheless reliable, accessible, and generalizable indices are required for planners and policymakers to promote sustainable water use systems. This study synthesizes a set of water use efficiency and productivity indices based on academic, industry and government literature in California and Australia, two locations with similarly water-stressed and valuable agricultural industries under pressure to achieve optimal water use efficiency and productivity. Empirical data at the irrigation district level from the California San Joaquin Valley and Murray Darling Basin states of Victoria and New South Wales in Australia are used to compute indices that estimate efficiency, yield productivity, and economic productivity of agricultural water use. Multiple index estimates of same time-series data demonstrate historical spread

  17. The reliability of jump kinematics and kinetics in children of different maturity status.

    Science.gov (United States)

    Meylan, Cesar M P; Cronin, John B; Oliver, Jon L; Hughes, Michael G; McMaster, D Travis

    2012-04-01

    The purpose of this study was to determine the reliability of eccentric (ECC) and concentric (CON) kinematic and kinetic variables thought to be critical to jump performance during bilateral vertical countermovement jump (VCMJ) and horizontal countermovement jump (HCMJ) across children of different maturity status. Forty-two athletic male and female participants between 9 and 16 years of age were divided into 3 maturity groups according to peak height velocity (PHV) offset (Post-PHV, At-PHV, and Pre-PHV) and percent of predicted adult stature. All the participants performed 3 VCMJ and HCMJ trials and the kinematics, and kinetics of these jumps were measured via a force plate over 3 testing sessions. In both jumps, vertical CON mean and peak power and jump height or distance were the most reliable measures across all groups (change in the mean [CM] = -5.4 to 6.2%; coefficient of variation [CV] = 2.1-9.4%; Intraclass correlation coefficient [ICC] = 0.82-0.98), whereas vertical ECC mean power was the only ECC variable with acceptable reliability for both jumps (CM = -0.7 to 10.1%; CV = 5.2-15.6%; ICC = 0.74-0.97). A less mature state was "likely" to "very likely" to reduce the reliability of the HCMJ ECC kinetics and kinematics. These findings suggested that movement variability is associated with the ECC phase of CMJs, especially in Pre-PHV during the HCMJ. Vertical CON mean and peak power and ECC mean power were deemed reliable and appropriate to be used in children as indicators of jump and stretch-shortening cycle performance.

  18. A Natural Component-Based Oxygen Indicator with In-Pack Activation for Intelligent Food Packaging.

    Science.gov (United States)

    Won, Keehoon; Jang, Nan Young; Jeon, Junsu

    2016-12-28

    Intelligent food packaging can provide consumers with reliable and correct information on the quality and safety of packaged foods. One of the key constituents in intelligent packaging is a colorimetric oxygen indicator, which is widely used to detect oxygen gas involved in food spoilage by means of a color change. Traditional oxygen indicators consisting of redox dyes and strong reducing agents have two major problems: they must be manufactured and stored under anaerobic conditions because air depletes the reductant, and their components are synthetic and toxic. To address both of these serious problems, we have developed a natural component-based oxygen indicator characterized by in-pack activation. The conventional oxygen indicator composed of synthetic and artificial components was redesigned using naturally occurring compounds (laccase, guaiacol, and cysteine). These natural components were physically separated into two compartments by a fragile barrier. Only when the barrier was broken were all of the components mixed and the function as an oxygen indicator was begun (i.e., in-pack activation). Depending on the component concentrations, the natural component-based oxygen indicator exhibited different response times and color differences. The rate of the color change was proportional to the oxygen concentration. This novel colorimetric oxygen indicator will contribute greatly to intelligent packaging for healthier and safer foods.

  19. Evaluating the reliability of an injury prevention screening tool: Test-retest study.

    Science.gov (United States)

    Gittelman, Michael A; Kincaid, Madeline; Denny, Sarah; Wervey Arnold, Melissa; FitzGerald, Michael; Carle, Adam C; Mara, Constance A

    2016-10-01

    A standardized injury prevention (IP) screening tool can identify family risks and allow pediatricians to address behaviors. To assess behavior changes on later screens, the tool must be reliable for an individual and ideally between household members. Little research has examined the reliability of safety screening tool questions. This study utilized test-retest reliability of parent responses on an existing IP questionnaire and also compared responses between household parents. Investigators recruited parents of children 0 to 1 year of age during admission to a tertiary care children's hospital. When both parents were present, one was chosen as the "primary" respondent. Primary respondents completed the 30-question IP screening tool after consent, and they were re-screened approximately 4 hours later to test individual reliability. The "second" parent, when present, only completed the tool once. All participants received a 10-dollar gift card. Cohen's Kappa was used to estimate test-retest reliability and inter-rater agreement. Standard test-retest criteria consider Kappa values: 0.0 to 0.40 poor to fair, 0.41 to 0.60 moderate, 0.61 to 0.80 substantial, and 0.81 to 1.00 as almost perfect reliability. One hundred five families participated, with five lost to follow-up. Thirty-two (30.5%) parent dyads completed the tool. Primary respondents were generally mothers (88%) and Caucasian (72%). Test-retest of the primary respondents showed their responses to be almost perfect; average 0.82 (SD = 0.13, range 0.49-1.00). Seventeen questions had almost perfect test-retest reliability and 11 had substantial reliability. However, inter-rater agreement between household members for 12 objective questions showed little agreement between responses; inter-rater agreement averaged 0.35 (SD = 0.34, range -0.19-1.00). One question had almost perfect inter-rater agreement and two had substantial inter-rater agreement. The IP screening tool used by a single individual had excellent

  20. Nurse staffing and system integration and change indicators in acute care hospitals: evidence from a balanced scorecard.

    Science.gov (United States)

    McGillis Hall, Linda; Peterson, Jessica; Baker, G Ross; Brown, Adalsteinn D; Pink, George H; McKillop, Ian; Daniel, Imtiaz; Pedersen, Cheryl

    2008-01-01

    This study examined relationships between financial indicators for nurse staffing and organizational system integration and change indicators. These indicators, along with hospital location and type, were examined in relation to the nursing financial indicators. Results showed that different indicators predicted each of the outcome variables. Nursing care hours were predicted by the hospital type, geographic location, and the system. Both nursing and patient care hours were significantly related to dissemination and benchmarking of clinical data.

  1. Analyzing the reliability of shuffle-exchange networks using reliability block diagrams

    International Nuclear Information System (INIS)

    Bistouni, Fathollah; Jahanshahi, Mohsen

    2014-01-01

    Supercomputers and multi-processor systems are comprised of thousands of processors that need to communicate in an efficient way. One reasonable solution would be the utilization of multistage interconnection networks (MINs), where the challenge is to analyze the reliability of such networks. One of the methods to increase the reliability and fault-tolerance of the MINs is use of various switching stages. Therefore, recently, the reliability of one of the most common MINs namely shuffle-exchange network (SEN) has been evaluated through the investigation on the impact of increasing the number of switching stage. Also, it is concluded that the reliability of SEN with one additional stage (SEN+) is better than SEN or SEN with two additional stages (SEN+2), even so, the reliability of SEN is better compared to SEN with two additional stages (SEN+2). Here we re-evaluate the reliability of these networks where the results of the terminal, broadcast, and network reliability analysis demonstrate that SEN+ and SEN+2 continuously outperform SEN and are very alike in terms of reliability. - Highlights: • The impact of increasing the number of stages on reliability of MINs is investigated. • The RBD method as an accurate method is used for the reliability analysis of MINs. • Complex series–parallel RBDs are used to determine the reliability of the MINs. • All measures of the reliability (i.e. terminal, broadcast, and network reliability) are analyzed. • All reliability equations will be calculated for different size N×N

  2. A Novel Analytic Technique for the Service Station Reliability in a Discrete-Time Repairable Queue

    Directory of Open Access Journals (Sweden)

    Renbin Liu

    2013-01-01

    Full Text Available This paper presents a decomposition technique for the service station reliability in a discrete-time repairable GeomX/G/1 queueing system, in which the server takes exhaustive service and multiple adaptive delayed vacation discipline. Using such a novel analytic technique, some important reliability indices and reliability relation equations of the service station are derived. Furthermore, the structures of the service station indices are also found. Finally, special cases and numerical examples validate the derived results and show that our analytic technique is applicable to reliability analysis of some complex discrete-time repairable bulk arrival queueing systems.

  3. Supporting change processes in design: Complexity, prediction and reliability

    Energy Technology Data Exchange (ETDEWEB)

    Eckert, Claudia M. [Engineering Design Centre, University of Cambridge, Trumpington Street, Cambridge, CB2 1PZ (United Kingdom)]. E-mail: cme26@cam.ac.uk; Keller, Rene [Engineering Design Centre, University of Cambridge, Trumpington Street, Cambridge, CB2 1PZ (United Kingdom)]. E-mail: rk313@cam.ac.uk; Earl, Chris [Open University, Department of Design and Innovation, Walton Hall, Milton Keynes MK7 6AA (United Kingdom)]. E-mail: C.F.Earl@open.ac.uk; Clarkson, P. John [Engineering Design Centre, University of Cambridge, Trumpington Street, Cambridge, CB2 1PZ (United Kingdom)]. E-mail: pjc10@cam.ac.uk

    2006-12-15

    Change to existing products is fundamental to design processes. New products are often designed through change or modification to existing products. Specific parts or subsystems are changed to similar ones whilst others are directly reused. Design by modification applies particularly to safety critical products where the reuse of existing working parts and subsystems can reduce cost and risk. However change is rarely a matter of just reusing or modifying parts. Changing one part can propagate through the entire design leading to costly rework or jeopardising the integrity of the whole product. This paper characterises product change based on studies in the aerospace and automotive industry and introduces tools to aid designers in understanding the potential effects of change. Two ways of supporting designers are described: probabilistic prediction of the effects of change and visualisation of change propagation through product connectivities. Change propagation has uncertainties which are amplified by the choices designers make in practice as they implement change. Change prediction and visualisation is discussed with reference to complexity in three areas of product development: the structural backcloth of connectivities in the existing product (and its processes), the descriptions of the product used in design and the actions taken to carry out changes.

  4. QA support for TFTR reliability improvement program in preparation for DT operation

    International Nuclear Information System (INIS)

    Parsells, R.F.; Howard, H.P.

    1987-01-01

    As TFTR approaches experiments in the Q=1 regime, machine reliability becomes a major variable in achieving experimental objectives. This paper describes the methods used to quantify current reliability levels, levels required for D-T operations, proposed methods for reliability growth and improvement, and tracking of reliability performance in that growth. Included in this scope are data collection techniques and short comings, bounding current reliability on the upper end, and requirements for D-T operations. Problem characterization through Pareto diagrams provides insight into recurrent failure modes and the use of Duane plots for charting of reliability changes both cumulative and instantaneous, is explained and demonstrated

  5. The reliability paradox: Why robust cognitive tasks do not produce reliable individual differences.

    Science.gov (United States)

    Hedge, Craig; Powell, Georgina; Sumner, Petroc

    2017-07-19

    Individual differences in cognitive paradigms are increasingly employed to relate cognition to brain structure, chemistry, and function. However, such efforts are often unfruitful, even with the most well established tasks. Here we offer an explanation for failures in the application of robust cognitive paradigms to the study of individual differences. Experimental effects become well established - and thus those tasks become popular - when between-subject variability is low. However, low between-subject variability causes low reliability for individual differences, destroying replicable correlations with other factors and potentially undermining published conclusions drawn from correlational relationships. Though these statistical issues have a long history in psychology, they are widely overlooked in cognitive psychology and neuroscience today. In three studies, we assessed test-retest reliability of seven classic tasks: Eriksen Flanker, Stroop, stop-signal, go/no-go, Posner cueing, Navon, and Spatial-Numerical Association of Response Code (SNARC). Reliabilities ranged from 0 to .82, being surprisingly low for most tasks given their common use. As we predicted, this emerged from low variance between individuals rather than high measurement variance. In other words, the very reason such tasks produce robust and easily replicable experimental effects - low between-participant variability - makes their use as correlational tools problematic. We demonstrate that taking such reliability estimates into account has the potential to qualitatively change theoretical conclusions. The implications of our findings are that well-established approaches in experimental psychology and neuropsychology may not directly translate to the study of individual differences in brain structure, chemistry, and function, and alternative metrics may be required.

  6. Regression analysis of the structure function for reliability evaluation of continuous-state system

    International Nuclear Information System (INIS)

    Gamiz, M.L.; Martinez Miranda, M.D.

    2010-01-01

    Technical systems are designed to perform an intended task with an admissible range of efficiency. According to this idea, it is permissible that the system runs among different levels of performance, in addition to complete failure and the perfect functioning one. As a consequence, reliability theory has evolved from binary-state systems to the most general case of continuous-state system, in which the state of the system changes over time through some interval on the real number line. In this context, obtaining an expression for the structure function becomes difficult, compared to the discrete case, with difficulty increasing as the number of components of the system increases. In this work, we propose a method to build a structure function for a continuum system by using multivariate nonparametric regression techniques, in which certain analytical restrictions on the variable of interest must be taken into account. Once the structure function is obtained, some reliability indices of the system are estimated. We illustrate our method via several numerical examples.

  7. Regression analysis of the structure function for reliability evaluation of continuous-state system

    Energy Technology Data Exchange (ETDEWEB)

    Gamiz, M.L., E-mail: mgamiz@ugr.e [Departamento de Estadistica e I.O., Facultad de Ciencias, Universidad de Granada, Granada 18071 (Spain); Martinez Miranda, M.D. [Departamento de Estadistica e I.O., Facultad de Ciencias, Universidad de Granada, Granada 18071 (Spain)

    2010-02-15

    Technical systems are designed to perform an intended task with an admissible range of efficiency. According to this idea, it is permissible that the system runs among different levels of performance, in addition to complete failure and the perfect functioning one. As a consequence, reliability theory has evolved from binary-state systems to the most general case of continuous-state system, in which the state of the system changes over time through some interval on the real number line. In this context, obtaining an expression for the structure function becomes difficult, compared to the discrete case, with difficulty increasing as the number of components of the system increases. In this work, we propose a method to build a structure function for a continuum system by using multivariate nonparametric regression techniques, in which certain analytical restrictions on the variable of interest must be taken into account. Once the structure function is obtained, some reliability indices of the system are estimated. We illustrate our method via several numerical examples.

  8. Microencapsulated Phase Change Materials in Solar-Thermal Conversion Systems: Understanding Geometry-Dependent Heating Efficiency and System Reliability.

    Science.gov (United States)

    Zheng, Zhaoliang; Chang, Zhuo; Xu, Guang-Kui; McBride, Fiona; Ho, Alexandra; Zhuola, Zhuola; Michailidis, Marios; Li, Wei; Raval, Rasmita; Akhtar, Riaz; Shchukin, Dmitry

    2017-01-24

    The performance of solar-thermal conversion systems can be improved by incorporation of nanocarbon-stabilized microencapsulated phase change materials (MPCMs). The geometry of MPCMs in the microcapsules plays an important role for improving their heating efficiency and reliability. Yet few efforts have been made to critically examine the formation mechanism of different geometries and their effect on MPCMs-shell interaction. Herein, through changing the cooling rate of original emulsions, we acquire MPCMs within the nanocarbon microcapsules with a hollow structure of MPCMs (h-MPCMs) or solid PCM core particles (s-MPCMs). X-ray photoelectron spectroscopy and atomic force microscopy reveals that the capsule shell of the h-MPCMs is enriched with nanocarbons and has a greater MPCMs-shell interaction compared to s-MPCMs. This results in the h-MPCMs being more stable and having greater heat diffusivity within and above the phase transition range than the s-MPCMs do. The geometry-dependent heating efficiency and system stability may have important and general implications for the fundamental understanding of microencapsulation and wider breadth of heating generating systems.

  9. Optimization and Reliability Problems in Structural Design of Wind Turbines

    DEFF Research Database (Denmark)

    Sørensen, John Dalsgaard

    2007-01-01

    are discussed. Limit state equations are presented for fatigue limit states and for ultimate limit states with extreme wind load, and illustrated by bending failure. Illustrative examples are presented, and as a part of the results optimal reliability levels are obtained which corresponds to an annual...... reliability index equal to 3. An example with fatigue failure indicates that the reliability level is almost the same for single wind turbines and for wind turbines in wind farms if the wake effects are modeled equivalently in the design equation and the limit state equation....

  10. Reliability data banks

    International Nuclear Information System (INIS)

    Cannon, A.G.; Bendell, A.

    1991-01-01

    Following an introductory chapter on Reliability, what is it, why it is needed, how it is achieved and measured, the principles of reliability data bases and analysis methodologies are the subject of the next two chapters. Achievements due to the development of data banks are mentioned for different industries in the next chapter, FACTS, a comprehensive information system for industrial safety and reliability data collection in process plants are covered next. CREDO, the Central Reliability Data Organization is described in the next chapter and is indexed separately, as is the chapter on DANTE, the fabrication reliability Data analysis system. Reliability data banks at Electricite de France and IAEA's experience in compiling a generic component reliability data base are also separately indexed. The European reliability data system, ERDS, and the development of a large data bank come next. The last three chapters look at 'Reliability data banks, - friend foe or a waste of time'? and future developments. (UK)

  11. Changes in lipid indices and body composition one year after laparoscopic gastrectomy: a prospective study.

    Science.gov (United States)

    Lee, Soo Jin; Kim, Ji Young; Ha, Tae Kyung; Choi, Yun Young

    2018-05-11

    The purpose of this prospective study was to investigate changes in lipid indices associated with whole body composition during 1 year of follow-up after laparoscopic gastrectomy. Thirty-seven patients with benign and malignant gastric neoplasm who underwent laparoscopic gastrectomy were prospectively enrolled. None of the patients were treated with adjuvant chemotherapy. Lipid indices and body composition were measured preoperatively and at six and 12 months after laparoscopic gastrectomy. Lipid indices included total cholesterol (TC), triglyceride (TG), low-density lipoprotein cholesterol (LDL-C) and high-density lipoprotein cholesterol (HDL-C). Body weight, fat and lean body mass (LBM) were measured by dual-energy X-ray absorptiometry and the change in fat and LBM in the trunk, arms and legs was compared. Body weight significantly decreased from 63.0 ± 11.1 kg preoperatively to 56.8 ± 10.6 kg 12 months after laparoscopic gastrectomy, with a mean of 7.1% (4.6 kg) weight loss. Fat and LBM loss contributed 68.4% (3.1 kg) and 30.1% (1.4 kg) of the total weight loss, respectively. In both the non-obese and obese groups, body weight, fat and LBM did not change significantly between 6 months and 12 months after gastrectomy. TC and LDL-C levels significantly decreased during the first six-month period and HDL-C significantly increased until 12 months after gastrectomy in the non-obese group. In the obese group, the degree of reduction in fat mass was significantly higher and the LBM/weight ratio significantly increased compared with the non-obese group. However, there was no significant change in lipid indices in the obese group. The TG level was significantly correlated with fat, especially with trunk fat. Gastrectomy resulted in improved lipid indices and a reduction in body weight, fat and LBM. The HDL-C significantly increased in the non-obese group for 1 year after gastrectomy and the reduction of TG level was positively correlated with fat

  12. The reliable solution and computation time of variable parameters Logistic model

    OpenAIRE

    Pengfei, Wang; Xinnong, Pan

    2016-01-01

    The reliable computation time (RCT, marked as Tc) when applying a double precision computation of a variable parameters logistic map (VPLM) is studied. First, using the method proposed, the reliable solutions for the logistic map are obtained. Second, for a time-dependent non-stationary parameters VPLM, 10000 samples of reliable experiments are constructed, and the mean Tc is then computed. The results indicate that for each different initial value, the Tcs of the VPLM are generally different...

  13. Snow reliability in ski resorts considering artificial snowmaking

    Science.gov (United States)

    Hofstätter, M.; Formayer, H.; Haas, P.

    2009-04-01

    Snow reliability is the key factor to make skiing on slopes possible and to ensure added value in winter tourism. In this context snow reliability is defined by the duration of a snowpack on the ski runs of at least 50 mm snow water equivalent (SWE), within the main season (Dec-Mar). Furthermore the snowpack should form every winter and be existent early enough in season. In our work we investigate the snow reliability of six Austrian ski resorts. Because nearly all Austrian resorts rely on artificial snowmaking it is of big importance to consider man made snow in the snowpack accumulation and ablation in addition to natural snow. For each study region observed weather data including temperature, precipitation and snow height are used. In addition we differentiate up to three elevations on each site (valley, intermediate, mountain top), being aware of the typical local winter inversion height. Time periods suitable for artificial snow production, for several temperature threshold (-6,-4 or -1 degree Celsius) are calculated on an hourly base. Depending on the actual snowpack height, man made snow can be added in the model with different defined capacities, considering different technologies or the usage of additives. To simulate natural snowpack accumulation and ablation we a simple snow model, based on daily precipitation and temperature. This snow model is optimized at each site separately through certain parameterization factors. Based on the local observations and the monthly climate change signals from the climate model REMO-UBA, we generate long term time series of temperature and precipitation, using the weather generator LARS. Thereby we are not only able to simulate the snow reliability under current, but also under future climate conditions. Our results show significant changes in snow reliability, like an increase of days with insufficient snow heights, especially at mid and low altitudes under natural snow conditions. Artificial snowmaking can partly

  14. Impact of climate change effecting Decline on Migration Birds of Bhadalwadi Lake Indapur Taluka M.S India

    OpenAIRE

    U.S .Gantaloo; Sangeeta B Dongare

    2016-01-01

    Environmental changes are now a day’s happening regularly day to day increase in temperature ,Scarcity of rainfall ,Drying of lakes have strong implication on Biodiversity .) .Global warming has set in motion and is affecting the timing of migration of birds .Birds are reliable indicator of environment change for centuries and their arrival indicate start of winter and departure summer in study area .There are many example of the effect of climate change on birds from all around t...

  15. Integration of NDE Reliability and Fracture Mechanics

    Energy Technology Data Exchange (ETDEWEB)

    Becker, F. L.; Doctor, S. R.; Heas!er, P. G.; Morris, C. J.; Pitman, S. G.; Selby, G. P.; Simonen, F. A.

    1981-03-01

    The Pacific Northwest Laboratory is conducting a four-phase program for measuring and evaluating the effectiveness and reliability of in-service inspection (lSI} performed on the primary system piping welds of commercial light water reactors (LWRs). Phase I of the program is complete. A survey was made of the state of practice for ultrasonic rsr of LWR primary system piping welds. Fracture mechanics calculations were made to establish required nondestrutive testing sensitivities. In general, it was found that fatigue flaws less than 25% of wall thickness would not grow to failure within an inspection interval of 10 years. However, in some cases failure could occur considerably faster. Statistical methods for predicting and measuring the effectiveness and reliability of lSI were developed and will be applied in the "Round Robin Inspections" of Phase II. Methods were also developed for the production of flaws typical of those found in service. Samples fabricated by these methods wilI be used in Phase II to test inspection effectiveness and reliability. Measurements were made of the influence of flaw characteristics {i.e., roughness, tightness, and orientation) on inspection reliability. These measurernents, as well as the predictions of a statistical model for inspection reliability, indicate that current reporting and recording sensitivities are inadequate.

  16. Reliability 'H' scheme of HV/MV substations

    Directory of Open Access Journals (Sweden)

    Perić Dragoslav M.

    2015-01-01

    Full Text Available Substations (HV/MV connect transmission and distribution systems with consumers of electric energy. The selective search method was used for calculation of substation reliability, where all arrangement elements were grouped into blocks. Subject of the analysis was H-arrangements comprising air-insulated switchgears on the high voltage side of HV/MV substations with different number of feeder and transformer bays and diverse scope of the installed switching equipment. Failure rate and duration were used as main HV/MV substation equipment reliability indices. A large number of arrangements were classified into groups, and within a group the arrangements were ranked with the use of multiple criteria. It is shown that the reliability of the electricity transit depends on the equipment of field for the transit of electricity, which favors poorly equipped field. On the other hand, the reliability of transformation of the full power depends mostly on the equipment in coupling field. It is essential that in the coupling field, there are at least two disconnectors. Installation of the switch in the coupling field is meaningful only with appropriate protection, because it further improves reliability. Conclusions are drawn for phased construction and expansion of the single pole diagram with an additional field for the transmission line.

  17. On the reliability of seasonal climate forecasts

    Science.gov (United States)

    Weisheimer, A.; Palmer, T. N.

    2014-01-01

    Seasonal climate forecasts are being used increasingly across a range of application sectors. A recent UK governmental report asked: how good are seasonal forecasts on a scale of 1–5 (where 5 is very good), and how good can we expect them to be in 30 years time? Seasonal forecasts are made from ensembles of integrations of numerical models of climate. We argue that ‘goodness’ should be assessed first and foremost in terms of the probabilistic reliability of these ensemble-based forecasts; reliable inputs are essential for any forecast-based decision-making. We propose that a ‘5’ should be reserved for systems that are not only reliable overall, but where, in particular, small ensemble spread is a reliable indicator of low ensemble forecast error. We study the reliability of regional temperature and precipitation forecasts of the current operational seasonal forecast system of the European Centre for Medium-Range Weather Forecasts, universally regarded as one of the world-leading operational institutes producing seasonal climate forecasts. A wide range of ‘goodness’ rankings, depending on region and variable (with summer forecasts of rainfall over Northern Europe performing exceptionally poorly) is found. Finally, we discuss the prospects of reaching ‘5’ across all regions and variables in 30 years time. PMID:24789559

  18. Modeling high-Power Accelerators Reliability-SNS LINAC (SNS-ORNL); MAX LINAC (MYRRHA)

    International Nuclear Information System (INIS)

    Pitigoi, A. E.; Fernandez Ramos, P.

    2013-01-01

    Improving reliability has recently become a very important objective in the field of particle accelerators. The particle accelerators in operation are constantly undergoing modifications, and improvements are implemented using new technologies, more reliable components or redundant schemes (to obtain more reliability, strength, more power, etc.) A reliability model of SNS (Spallation Neutron Source) LINAC has been developed within MAX project and analysis of the accelerator systems reliability has been performed within the MAX project, using the Risk Spectrum reliability analysis software. The analysis results have been evaluated by comparison with the SNS operational data. Results and conclusions are presented in this paper, oriented to identify design weaknesses and provide recommendations for improving reliability of MYRRHA linear accelerator. The SNS reliability model developed for the MAX preliminary design phase indicates possible avenues for further investigation that could be needed to improve the reliability of the high-power accelerators, in view of the future reliability targets of ADS accelerators.

  19. Use of color-change indicators to quantify passive films on the stainless steel valves of nuclear power plants

    Energy Technology Data Exchange (ETDEWEB)

    Cheng, Cong Qian [School of Materials Science, Engineering, Dalian University of Technology, Dalian 116085 (China); Yang, Shu Kai [School of Materials Science, Engineering, Dalian University of Technology, Dalian 116085 (China); Suzhou Nuclear Power Research Institute, Suzhou 215004 (China); Zhao, Jie, E-mail: jiezhao@dlut.edu.cn [School of Materials Science, Engineering, Dalian University of Technology, Dalian 116085 (China)

    2016-02-15

    Highlights: • A facile method to evaluate passivation quality by color change indicator. • Two indicators were compared in lab and applied on vales in nuclear power plants. • It shows that the higher value of color change the worse quality of passivation. • Traditional ferroxyl solution is unstable and might impair the vale surface. • The new indicator is more practicable than the ferroxyl test for on-site inspection. - Abstract: The passive film on nuclear-grade stainless steels was evaluated by quantifying its color changes. Coloration reactions were compared by using ferroin and blue dot solutions as indicators on the basis of the measured results in a laboratory. The reactions were then applied on stainless steel valves in a nuclear power plant. The degree of color change indicates the degree of growth of a passive film. The ferroin solution exhibits higher accuracy and more stable than blue dot solution in determining passive film quality. The potentiodynamic polarization curves show that blue dot solution might cause surface damage compared with ferroin solution. The inspection result on stainless steel valves supports our laboratory result. However, stainless steel exhibited a dramatic decrease in sensitivity to blue dot because of the intrinsic instability and high acidity of this solution. Ferroin solution is superior to blue dot solution for stainless steel facilities in a nuclear power plant.

  20. Performance Indicators for Online Geography in Secondary Education

    NARCIS (Netherlands)

    van Diepen, P.; Bredeweg, B.; Bosse, T.; Bredeweg, B.

    2016-01-01

    There is little consensus about what variables extracted from learner data are the most reliable indicators of learning performance. The aim of this study was to determine those indicators by taking a wide range of variables into consideration concerning overall learning activity and content

  1. Use of eye tracking equipment for human reliability analysis applied to complex system operations

    International Nuclear Information System (INIS)

    Pinheiro, Andre Ricardo Mendonça; Prado, Eugenio Anselmo Pessoa do; Martins, Marcelo Ramos

    2017-01-01

    This article will discuss the preliminary results of an evaluation methodology for the analysis and quantification of manual character errors (human), by monitoring cognitive parameters and skill levels in the operation of a complex control system based on parameters provided by a eye monitoring equipment (Eye Tracker). The research was conducted using a simulator (game) that plays concepts of operation of a nuclear reactor with a split sample for evaluation of aspects of learning, knowledge and standard operating within the context addressed. bridge operators were monitored using the EYE TRACKING, eliminating the presence of the analyst in the evaluation of the operation, allowing the analysis of the results by means of multivariate statistical techniques within the scope of system reliability. The experiments aim to observe state change situations such as stops and scheduled departures, incidents assumptions and common operating characteristics. Preliminary results of this research object indicate that technical and cognitive aspects can contribute to improving the reliability of the available techniques in human reliability, making them more realistic both in the context of quantitative approaches to regulatory and training purposes, as well as reduced incidence of human error. (author)

  2. Use of eye tracking equipment for human reliability analysis applied to complex system operations

    Energy Technology Data Exchange (ETDEWEB)

    Pinheiro, Andre Ricardo Mendonça; Prado, Eugenio Anselmo Pessoa do; Martins, Marcelo Ramos, E-mail: andrericardopinheiro@usp.br, E-mail: eugenio.prado@labrisco.usp.br, E-mail: mrmatins@usp.br [Universidade de Sao Paulo (LABRISCO/USP), Sao Paulo, SP (Brazil). Lab. de Análise, Avaliação e Gerenciamento de Risco

    2017-07-01

    This article will discuss the preliminary results of an evaluation methodology for the analysis and quantification of manual character errors (human), by monitoring cognitive parameters and skill levels in the operation of a complex control system based on parameters provided by a eye monitoring equipment (Eye Tracker). The research was conducted using a simulator (game) that plays concepts of operation of a nuclear reactor with a split sample for evaluation of aspects of learning, knowledge and standard operating within the context addressed. bridge operators were monitored using the EYE TRACKING, eliminating the presence of the analyst in the evaluation of the operation, allowing the analysis of the results by means of multivariate statistical techniques within the scope of system reliability. The experiments aim to observe state change situations such as stops and scheduled departures, incidents assumptions and common operating characteristics. Preliminary results of this research object indicate that technical and cognitive aspects can contribute to improving the reliability of the available techniques in human reliability, making them more realistic both in the context of quantitative approaches to regulatory and training purposes, as well as reduced incidence of human error. (author)

  3. Behavioral reliability program for the nuclear industry. Technical report

    International Nuclear Information System (INIS)

    Buchanan, J.C.; Davis, S.O.; Dunnette, M.D.; Meyer, P.; Sharac, J.

    1981-07-01

    The subject of the study was the development of standards for a behavioral observation program which could be used by the NRC licensed nuclear industry to detect indications of emotional instability in its employees who have access to protected and vital areas. Emphasis was placed on those observable characteristics which could be assessed by supervisors or peers in a work environment. The behavioral reliability program, as was defined in this report, encompasses the concept and basic components of the program, the definition of the behavioral reliability program, the definition of the behavioral reliability criterion, and a set of instructions for the creation and implementation of the program by an individual facility

  4. How well are the climate indices related to the GRACE-observed total water storage changes in China?

    Science.gov (United States)

    Devaraju, B.; Vishwakarma, B.; Sneeuw, N. J.

    2017-12-01

    The fresh water availability over land masses is changing rapidly under the influence of climate change and human intervention. In order to manage our water resources and plan for a better future, we need to demarcate the role of climate change. The total water storage change in a region can be obtained from the GRACE satellite mission. On the other hand, many climate change indicators, for example ENSO, are derived from sea surface temperature. In this contribution we investigate the relationship between the total water storage change over China with the climate indices using statistical time-series decomposition techniques, such as Seasonal and Trend decomposition using Loess (STL), Principal Component Analysis (PCA) and Canonical Correlation Analysis (CCA). The anomalies in climate variables, such as sea surface temperature, are responsible for anomalous precipitation and thus an anomalous total water storage change over land. Therefore, it is imperative that we use a GRACE product that can capture anomalous water storage changes with unprecedented accuracy. Since filtering decreases the sensitivity of GRACE products substantially, we use the data-driven method of deviation for recovering the signal lost due to filtering. To this end, we are able to obtain the spatial fingerprint of individual climate index on total water storage change observed over China.

  5. Estimating Between-Person and Within-Person Subscore Reliability with Profile Analysis.

    Science.gov (United States)

    Bulut, Okan; Davison, Mark L; Rodriguez, Michael C

    2017-01-01

    Subscores are of increasing interest in educational and psychological testing due to their diagnostic function for evaluating examinees' strengths and weaknesses within particular domains of knowledge. Previous studies about the utility of subscores have mostly focused on the overall reliability of individual subscores and ignored the fact that subscores should be distinct and have added value over the total score. This study introduces a profile reliability approach that partitions the overall subscore reliability into within-person and between-person subscore reliability. The estimation of between-person reliability and within-person reliability coefficients is demonstrated using subscores from number-correct scoring, unidimensional and multidimensional item response theory scoring, and augmented scoring approaches via a simulation study and a real data study. The effects of various testing conditions, such as subtest length, correlations among subscores, and the number of subtests, are examined. Results indicate that there is a substantial trade-off between within-person and between-person reliability of subscores. Profile reliability coefficients can be useful in determining the extent to which subscores provide distinct and reliable information under various testing conditions.

  6. Eutectic mixtures of some fatty acids for latent heat storage: Thermal properties and thermal reliability with respect to thermal cycling

    International Nuclear Information System (INIS)

    Sari, Ahmet

    2006-01-01

    Accelerated thermal cycle tests have been conducted to study the change in melting temperatures and latent heats of fusion of the eutectic mixtures of lauric acid (LA)-myristic acid (MA), lauric acid (LA)-palmitic acid (PA) and myristic acid (MA)-stearic acid (SA) as latent heat storage materials. The thermal properties of these materials were determined by the differential scanning calorimetry (DSC) analysis method. The thermal reliability of the eutectic mixtures after melt/freeze cycles of 720, 1080 and 1460 was also evaluated using the DSC curves. The accelerated thermal cycle tests indicate that the melting temperatures usually tend to decrease, and the variations in the latent heats of fusion are irregular with increasing number of thermal cycles. Moreover, the probable reasons for the change in thermal properties of the eutectic mixtures after repeated thermal cycles were investigated. Fourier Transform Infrared (FT-IR) spectroscopic analysis indicates that the accelerated melt/freeze processes do not cause any degradation in the chemical structure of the mixtures. The change in thermal properties of the eutectic mixtures with increasing number of thermal cycles is only because of the presence of certain amounts of impurities in the fatty acids used in their preparation. It is concluded that the tested eutectic mixtures have reasonable thermal properties and thermal reliability as phase change materials (PCMs) for latent heat storage in any solar heating applications that include a four year utilization period

  7. Scyllac equipment reliability analysis

    International Nuclear Information System (INIS)

    Gutscher, W.D.; Johnson, K.J.

    1975-01-01

    Most of the failures in Scyllac can be related to crowbar trigger cable faults. A new cable has been designed, procured, and is currently undergoing evaluation. When the new cable has been proven, it will be worked into the system as quickly as possible without causing too much additional down time. The cable-tip problem may not be easy or even desirable to solve. A tightly fastened permanent connection that maximizes contact area would be more reliable than the plug-in type of connection in use now, but it would make system changes and repairs much more difficult. The balance of the failures have such a low occurrence rate that they do not cause much down time and no major effort is underway to eliminate them. Even though Scyllac was built as an experimental system and has many thousands of components, its reliability is very good. Because of this the experiment has been able to progress at a reasonable pace

  8. Reliability calculations

    International Nuclear Information System (INIS)

    Petersen, K.E.

    1986-03-01

    Risk and reliability analysis is increasingly being used in evaluations of plant safety and plant reliability. The analysis can be performed either during the design process or during the operation time, with the purpose to improve the safety or the reliability. Due to plant complexity and safety and availability requirements, sophisticated tools, which are flexible and efficient, are needed. Such tools have been developed in the last 20 years and they have to be continuously refined to meet the growing requirements. Two different areas of application were analysed. In structural reliability probabilistic approaches have been introduced in some cases for the calculation of the reliability of structures or components. A new computer program has been developed based upon numerical integration in several variables. In systems reliability Monte Carlo simulation programs are used especially in analysis of very complex systems. In order to increase the applicability of the programs variance reduction techniques can be applied to speed up the calculation process. Variance reduction techniques have been studied and procedures for implementation of importance sampling are suggested. (author)

  9. A COMPUTERIZED DIAGNOSTIC COMPLEX FOR RELIABILITY TESTING OF ELECTRIC MACHINES

    Directory of Open Access Journals (Sweden)

    O.О. Somka

    2015-06-01

    Full Text Available Purpose. To develop a diagnostic complex meeting the criteria and requirements for carrying out accelerated reliability test and realizing the basic modes of electric machines operation and performance of the posed problems necessary in the process of such test. Methodology. To determine and forecast the indices of electric machines reliability in accordance with the statistic data of repair plants we have conditionally divided them into structural parts that are most likely to fail. We have preliminarily assessed the state of each of these parts, which includes revelation of faults and deviations of technical and geometric parameters. We have determined the analyzed electric machine controlled parameters used for assessment of quantitative characteristics of reliability of these parts and electric machines on the whole. Results. As a result of the research, we have substantiated the structure of a computerized complex for electric machines reliability test. It allows us to change thermal and vibration actions without violation of the physics of the processes of aging and wearing of the basic structural parts and elements material. The above mentioned makes it possible to considerably reduce time spent on carrying out electric machines reliability tests and improve trustworthiness of the data obtained as a result of their performance. Originality. A special feature of determination of the controlled parameters consists in removal of vibration components in the idle mode and after disconnection of the analyzed electric machine from the power supply with the aim of singling out the vibration electromagnetic component, fixing the degree of sparking and bend of the shaft by means of phototechnique and local determination of structural parts temperature provided by corresponding location of thermal sensors. Practical value. We have offered a scheme of location of thermal and vibration sensors, which allows improvement of parameters measuring accuracy

  10. [Validation and adhesion to GESIDA quality indicators in patients with HIV infection].

    Science.gov (United States)

    Riera, Melchor; Esteban, Herminia; Suarez, Ignacio; Palacios, Rosario; Lozano, Fernando; Blanco, Jose R; Valencia, Eulalia; Ocampo, Antonio; Amador, Concha; Frontera, Guillem; vonWichmann-de Miguel, Miguel Angel

    2016-01-01

    The objective of the study is to validate the relevant GESIDA quality indicators for HIV infection, assessing the reliability, feasibility and adherence to them. The reliability was evaluated using the reproducibility of 6 indicators in peer review, with the second observer being an outsider. The feasibility and measurement of the level of adherence to the 22 indicators was conducted with annual fragmented retrospective collection of information from specific databases or the clinical charts of the nine participating hospitals. Reliability was very high, with interobserver agreement levels higher than 95% in 5 of the 6 indicators. The median time to achieve the indicators ranged between 5 and 600minutes, but could be achieved progressively from specific databases, enabling obtaining them automatically. As regards adherence to the indicators related with the initial evaluation of the patients, instructions and suitability of the guidelines for ART, adherence to ART, follow-up in clinics, and achieve an undetectable HIV by PCR at week 48 of the ART. Indicators of quality related to the prevention of opportunistic infections and control of comorbidities, the standards set were not achieved, and significant heterogeneity was observed between hospitals. The GESIDA quality indicators of HIV infection enabled the relevant indicators to be feasibly and reliably measured, and should be collected in all the units that care for patients with HIV infection. Copyright © 2015 Elsevier España, S.L.U. and Sociedad Española de Enfermedades Infecciosas y Microbiología Clínica. All rights reserved.

  11. Validity and Reliability Testing of an e-learning Questionnaire for Chemistry Instruction

    Science.gov (United States)

    Guspatni, G.; Kurniawati, Y.

    2018-04-01

    The aim of this paper is to examine validity and reliability of a questionnaire used to evaluate e-learning implementation in chemistry instruction. 48 questionnaires were filled in by students who had studied chemistry through e-learning system. The questionnaire consisted of 20 indicators evaluating students’ perception on using e-learning. Parametric testing was done as data were assumed to follow normal distribution. Item validity of the questionnaire was examined through item-total correlation using Pearson’s formula while its reliability was assessed with Cronbach’s alpha formula. Moreover, convergent validity was assessed to see whether indicators building a factor had theoretically the same underlying construct. The result of validity testing revealed 19 valid indicators while the result of reliability testing revealed Cronbach’s alpha value of .886. The result of factor analysis showed that questionnaire consisted of five factors, and each of them had indicators building the same construct. This article shows the importance of factor analysis to get a construct valid questionnaire before it is used as research instrument.

  12. Transfusion of Packed Red Blood Cells--The Indications Have Changed.

    Science.gov (United States)

    Cook, Alan; Miller, Nate

    2015-12-01

    Whole blood/packed red blood cells (pRBC) units transfused in the U.S. totaled 13,785,000 in 2011. A single institution in South Dakota transfused 6,485 units of pRBC in 2013. Current thresholds for transfusion have changed and each transfusion has the risk of causing an adverse reaction; thus, it is important to ensure pRBCs are administered appropriately. Due to these changes and the potential risks associated with transfusion, we reviewed the literature regarding appropriate indications for transfusion of pRBC. Our review specifically focused on four disease entities: iron-deficiency anemia, acute upper gastrointestinal (GI) bleeding, acute coronary syndromes, and chronic ischemic heart disease. Based on our findings, we recommend utilizing an overall conservative approach to the transfusion of pRBC. In patients with iron-deficiency anemia, first try alternative methods to improve hemoglobin levels; in those with acute GI bleeding, transfuse for hemoglobin less than 7 g/dL; in patients with acute coronary syndromes, let symptoms/signs be your guide; and in patients with ischemic heart disease, transfuse for hemoglobin levels less than 8 g/dL or if they are symptomatic. Most importantly, be cautious to not fixate on numbers alone; always incorporate patients' symptoms and co-morbidities when considering whether to transfuse pRBCs.

  13. Comparison of Flood Vulnerability Assessments to Climate Change by Construction Frameworks for a Composite Indicator

    Directory of Open Access Journals (Sweden)

    Jong Seok Lee

    2018-03-01

    Full Text Available As extreme weather conditions due to climate change can cause deadly flood damages all around the world, a role of the flood vulnerability assessment has become recognized as one of the preemptive measures in nonstructural flood mitigation strategies. Although the flood vulnerability is most commonly assessed by a composite indicator compiled from multidimensional phenomena and multiple conflicting criteria associated with floods, directly or indirectly, it has been often overlooked that the construction frameworks and processes can have a significant influence on the flood vulnerability indicator outcomes. This study has, therefore, compared the flood vulnerability ranking orders for the 54 administrative districts in the Nakdong River Watershed of the Korean Peninsula, ranked from composite indicators by different frameworks and multi-attribute utility functions for combining the three assessment components, such as exposure, sensitivity, and coping, presented in the IPCC Third Assessment Report. The results show that the different aggregation components and utility functions under the same proxy variable system can lead to larger volatility of flood vulnerability rankings than expected. It is concluded that the vulnerability indicator needs to be derived from all three assessment components by a multiplicative utility function for a desirable flood vulnerability assessment to climate change.

  14. Reliability-based condition assessment of steel containment and liners

    International Nuclear Information System (INIS)

    Ellingwood, B.; Bhattacharya, B.; Zheng, R.

    1996-11-01

    Steel containments and liners in nuclear power plants may be exposed to aggressive environments that may cause their strength and stiffness to decrease during the plant service life. Among the factors recognized as having the potential to cause structural deterioration are uniform, pitting or crevice corrosion; fatigue, including crack initiation and propagation to fracture; elevated temperature; and irradiation. The evaluation of steel containments and liners for continued service must provide assurance that they are able to withstand future extreme loads during the service period with a level of reliability that is sufficient for public safety. Rational methodologies to provide such assurances can be developed using modern structural reliability analysis principles that take uncertainties in loading, strength, and degradation resulting from environmental factors into account. The research described in this report is in support of the Steel Containments and Liners Program being conducted for the US Nuclear Regulatory Commission by the Oak Ridge National Laboratory. The research demonstrates the feasibility of using reliability analysis as a tool for performing condition assessments and service life predictions of steel containments and liners. Mathematical models that describe time-dependent changes in steel due to aggressive environmental factors are identified, and statistical data supporting the use of these models in time-dependent reliability analysis are summarized. The analysis of steel containment fragility is described, and simple illustrations of the impact on reliability of structural degradation are provided. The role of nondestructive evaluation in time-dependent reliability analysis, both in terms of defect detection and sizing, is examined. A Markov model provides a tool for accounting for time-dependent changes in damage condition of a structural component or system. 151 refs

  15. Reliability estimation for multiunit nuclear and fossil-fired industrial energy systems

    International Nuclear Information System (INIS)

    Sullivan, W.G.; Wilson, J.V.; Klepper, O.H.

    1977-01-01

    As petroleum-based fuels grow increasingly scarce and costly, nuclear energy may become an important alternative source of industrial energy. Initial applications would most likely include a mix of fossil-fired and nuclear sources of process energy. A means for determining the overall reliability of these mixed systems is a fundamental aspect of demonstrating their feasibility to potential industrial users. Reliability data from nuclear and fossil-fired plants are presented, and several methods of applying these data for calculating the reliability of reasonably complex industrial energy supply systems are given. Reliability estimates made under a number of simplifying assumptions indicate that multiple nuclear units or a combination of nuclear and fossil-fired plants could provide adequate reliability to meet industrial requirements for continuity of service

  16. SGHWR fuel performance, safety and reliability

    International Nuclear Information System (INIS)

    Pickman, D.O.; Inglis, G.H.

    1977-05-01

    The design principles involved in fuel pins and elements need to take account of the sometimes conflicting requirements of safety and reliability. The principal factors involved in this optimisation are discussed and it is shown from fuel irradiation experience in the Winfrith SGHWR that the necessary bias towards safety has not resulted in a reliability level lower than that shown by other successful water reactor designs. Reliability has important economic implications. By a detailed evaluation of SGHWR fuel defects it is shown that very few defects can be shown to be related to design, rating, or burn-up. This demonstrates that economic aspects have not over-ridden necessary criteria that most be met to achieve the desirable reliability level. It is possible that large scale experience on SGHWR fuel may eventually demonstrate that the balance is too much in favour of reliability and consideration may be given to whether design changes favouring economy could be achieved without compromising safety. The safety criteria applied to SGHWR fuel are designed to avoid any possibility of a temperature runaway in any credible accident situation. the philosophy and supporting experimental work programme are outlines and the fuel design features which particularly contribute to maximising safety margins are outlined. Reference is made to the new 60-pin fuel element to be used in the commercial SGHWRs and to its comparison in design and performance aspects with the 36-pin element that has been used to date in the Winfrith SGHWR. (author)

  17. Using wind plant data to increase reliability.

    Energy Technology Data Exchange (ETDEWEB)

    Peters, Valerie A. (Sandia National Laboratories, Livermore, CA); Ogilvie, Alistair B.; McKenney, Bridget L.

    2011-01-01

    Operators interested in improving reliability should begin with a focus on the performance of the wind plant as a whole. To then understand the factors which drive individual turbine performance, which together comprise the plant performance, it is necessary to track a number of key indicators. Analysis of these key indicators can reveal the type, frequency, and cause of failures and will also identify their contributions to overall plant performance. The ideal approach to using data to drive good decisions includes first determining which critical decisions can be based on data. When those required decisions are understood, then the analysis required to inform those decisions can be identified, and finally the data to be collected in support of those analyses can be determined. Once equipped with high-quality data and analysis capabilities, the key steps to data-based decision making for reliability improvements are to isolate possible improvements, select the improvements with largest return on investment (ROI), implement the selected improvements, and finally to track their impact.

  18. Reliability analysis of neutron flux monitoring system for PFBR

    International Nuclear Information System (INIS)

    Rajesh, M.G.; Bhatnagar, P.V.; Das, D.; Pithawa, C.K.; Vinod, Gopika; Rao, V.V.S.S.

    2010-01-01

    The Neutron Flux Monitoring System (NFMS) measures reactor power, rate of change of power and reactivity changes in the core in all states of operation and shutdown. The system consists of instrument channels that are designed and built to have high reliability. All channels are required to have a Mean Time Between Failures (MTBF) of 150000 hours minimum. Failure Mode and Effects Analysis (FMEA) and failure rate estimation of NFMS channels has been carried out. FMEA is carried out in compliance with MIL-STD-338B. Reliability estimation of the channels is done according to MIL-HDBK-217FN2. Paper discusses the methodology followed for FMEA and failure rate estimation of two safety channels and results. (author)

  19. Automated evaluation of ultrasonic indications

    International Nuclear Information System (INIS)

    Hansch, M.K.T.; Stegemann, D.

    1994-01-01

    Future requirements of reliability and reproducibility in quality assurance demand computer evaluation of defect indications. The ultrasonic method with its large field of applications and a high potential for automation provides all preconditions for fully automated inspection. The survey proposes several desirable hardware improvements, data acquisition requirements and software configurations. (orig.) [de

  20. Maynard Smith: amplifying the reasons for signal reliability.

    Science.gov (United States)

    Harper, D G C

    2006-03-21

    One of the many questions to which John Maynard Smith contributed was that of why most animal signals are reliable. He initially rejected the "handicap" argument but gradually accepted it, a process I briefly describe. This episode illustrated his preference for mathematical models over verbal ones, and the generosity with which he could change his mind. Even after accepting that some signals are reliable because of their strategic costs, he argued for a pluralistic approach to signal reliability. Signal complexity was a developing interest when he died. Signals usually involve several components, some of which appear to amplify other signal components. The terms "amplifier" and "index" require more thought to reduce the scope for semantic confusion. I conclude by describing Maynard Smith's fascination with peacocks Pavo cristatus.

  1. WWER-1000 unit reliability problems from the point of view of the main supplier of technological equipment

    International Nuclear Information System (INIS)

    Bursa, V.; Holousova, M.; Turnik, S.

    1990-01-01

    At Skoda Works in Plzen, data from the period of construction of nuclear power plants are processed on an ICL DRS 300 computer. The database systems DBASE II and DATAFLEX are available for creating reliability information systems. The information system that is being developed for WWER-1000 units is tested at the WWER-440 units of the Dukovany and Mochovce nuclear power plants. Activities in the field of evaluation of structure reliability of WWER-1000 nuclear power plants are aimed at two major goals, viz., developing a methodology for testing the reliability of the whole unit and its subsystems, and performing reliability analysis and calculations of reliability indices of the secondary circuit of a WWER-1000 nuclear power plant. The reason for the latter concern is the fact that in 1984-1986, secondary circuits contributed 46% to failures of Czechoslovak WWER-440 nuclear power plants. According to existing analyses, the time fluctuations of reliability indices obey no rule that could be employed for inferring indices expected in steady-state operating conditions from indices established in the starting stage of operation. (Z.M.). 10 refs

  2. Reliability of impedance cardiography in measuring central haemodynamics

    DEFF Research Database (Denmark)

    Mehlsen, J; Bonde, J; Stadeager, C

    1991-01-01

    The purpose of the study described here was to investigate the reliability of impedance cardiography (IC) in measuring cardiac output (CO) and central blood volume. Absolute values and changes in these variables obtained by impedance cardiography and by isotope- or thermodilution techniques were...... suitable for repeated measurements in studies on the haemodynamic effects of physiological or pharmacological intervention. Impedance cardiography is sufficiently reliable for comparison of absolute values of CO between different groups of patients. We cannot recommend impedance cardiography...... healthy subjects and in 25 unmedicated patients with ischaemic heart disease. We obtained significant correlations between absolute values (y = 0.68x + 1.48) and changes (y = 1.00x + 0.0003) in CO measured by IC and isotope- or thermodilution. IC significantly overestimated absolute values of CO (P less...

  3. Reliability-Based Decision Fusion in Multimodal Biometric Verification Systems

    Directory of Open Access Journals (Sweden)

    Kryszczuk Krzysztof

    2007-01-01

    Full Text Available We present a methodology of reliability estimation in the multimodal biometric verification scenario. Reliability estimation has shown to be an efficient and accurate way of predicting and correcting erroneous classification decisions in both unimodal (speech, face, online signature and multimodal (speech and face systems. While the initial research results indicate the high potential of the proposed methodology, the performance of the reliability estimation in a multimodal setting has not been sufficiently studied or evaluated. In this paper, we demonstrate the advantages of using the unimodal reliability information in order to perform an efficient biometric fusion of two modalities. We further show the presented method to be superior to state-of-the-art multimodal decision-level fusion schemes. The experimental evaluation presented in this paper is based on the popular benchmarking bimodal BANCA database.

  4. Looking for spectral changes occurring during storage of ultra-cold neutrons

    Energy Technology Data Exchange (ETDEWEB)

    Steyerl, A; Malik, S S [Rhode Island Univ., Kingston, RI (United States); Geltenbort, P [Institut Max von Laue - Paul Langevin (ILL), 38 -Grenoble (France)

    1997-04-01

    It seems that the spectrum of ultra-cold neutrons does change. The measured data indicate with 5{sigma} reliability, that a small heating by about 2{center_dot}10{sup -10} eV ({approx} 2 mm of rise height against the earth`s gravity) occurred during the initial {approx} 10{sup 3} wall reflections, and no change thereafter. The reason of this effect is searched for. (author). 3 refs.

  5. Interactive reliability assessment using an integrated reliability data bank

    International Nuclear Information System (INIS)

    Allan, R.N.; Whitehead, A.M.

    1986-01-01

    The logical structure, techniques and practical application of a computer-aided technique based on a microcomputer using floppy disc Random Access Files is described. This interactive computational technique is efficient if the reliability prediction program is coupled directly to a relevant source of data to create an integrated reliability assessment/reliability data bank system. (DG)

  6. Indication of Changes in Projecting Organizational Structures Under the New Economy

    Directory of Open Access Journals (Sweden)

    Pártlová Petra

    2017-09-01

    Full Text Available Enterprise Architecture includes organizational and management part and visions and goals of the organization, business processes leading to the goals, innovation processes, control mechanisms, information and communication technologies and others. The paper focuses on one of the most important components of corporate architecture, organizational and management framework of an enterprise in terms of its present state and anticipated changes and the expected development in the context of the emerging new economy. The research was carried out in a sample of 372 enterprises from the whole Czech Republic with the sector (industrial, manufacturing, services and primary sector and size differentiation (micro-enterprises, small and medium-sized enterprises and large enterprises according to the classification of Ministry of Industry and Trade of the Czech Republic and the EU. The statistical methods were used (p-value with Pearson Chi quadrate output to analyses the results. The conclusion indicates a possible development in the corporate organization architecture in the context of the paradigm of changes in the external corporate environment.

  7. Structural reliability analysis based on the cokriging technique

    International Nuclear Information System (INIS)

    Zhao Wei; Wang Wei; Dai Hongzhe; Xue Guofeng

    2010-01-01

    Approximation methods are widely used in structural reliability analysis because they are simple to create and provide explicit functional relationships between the responses and variables in stead of the implicit limit state function. Recently, the kriging method which is a semi-parameter interpolation technique that can be used for deterministic optimization and structural reliability has gained popularity. However, to fully exploit the kriging method, especially in high-dimensional problems, a large number of sample points should be generated to fill the design space and this can be very expensive and even impractical in practical engineering analysis. Therefore, in this paper, a new method-the cokriging method, which is an extension of kriging, is proposed to calculate the structural reliability. cokriging approximation incorporates secondary information such as the values of the gradients of the function being approximated. This paper explores the use of the cokriging method for structural reliability problems by comparing it with the Kriging method based on some numerical examples. The results indicate that the cokriging procedure described in this work can generate approximation models to improve on the accuracy and efficiency for structural reliability problems and is a viable alternative to the kriging.

  8. The effect of loss functions on empirical Bayes reliability analysis

    Directory of Open Access Journals (Sweden)

    Camara Vincent A. R.

    1998-01-01

    Full Text Available The aim of the present study is to investigate the sensitivity of empirical Bayes estimates of the reliability function with respect to changing of the loss function. In addition to applying some of the basic analytical results on empirical Bayes reliability obtained with the use of the “popular” squared error loss function, we shall derive some expressions corresponding to empirical Bayes reliability estimates obtained with the Higgins–Tsokos, the Harris and our proposed logarithmic loss functions. The concept of efficiency, along with the notion of integrated mean square error, will be used as a criterion to numerically compare our results. It is shown that empirical Bayes reliability functions are in general sensitive to the choice of the loss function, and that the squared error loss does not always yield the best empirical Bayes reliability estimate.

  9. 76 FR 23222 - Electric Reliability Organization Interpretation of Transmission Operations Reliability

    Science.gov (United States)

    2011-04-26

    ....3d 1342 (DC Cir. 2009). \\5\\ Mandatory Reliability Standards for the Bulk-Power System, Order No. 693... Reliability Standards for the Bulk-Power System. Action: FERC-725A. OMB Control No.: 1902-0244. Respondents...] Electric Reliability Organization Interpretation of Transmission Operations Reliability AGENCY: Federal...

  10. Coastline degradation as an indicator of global change

    Science.gov (United States)

    Nicholls, Robert J.; Woodroffe, Colin D.; Burkett, Virginia; Letcher, Trevor M.

    2009-01-01

    Finding a climate change signal on coasts is more problematic than often assumed. Coasts undergo natural dynamics at many scales, with erosion and recovery in response to climate variability such as El Niño, or extreme events such as storms and infrequent tsunamis. Additionally, humans have had enormous impacts on most coasts, overshadowing most changes that one can presently attribute directly to climate change. Each area of coast is experiencing its own pattern of relative sea-level change and climate change, making discrimination of the component of degradation that results from climate change problems. The best examples of a climate influence are related to temperature rise at low and high latitudes, as seen by the impacts on coral reefs and polar coasts, respectively. Observations through the twentieth century demonstrate the importance of understanding the impacts of sea-level rise and climate change in the context of multiple drivers of change; this will remain a challenge under a more rapidly changing climate. Nevertheless, there are emerging signs that climate change provides a global threat—sea ice is retreating, permafrost in coastal areas is widely melting. Reefs are bleaching more often, and the sea is rising—amplifying widespread trends of subsidence and threatening low-lying areas. To enhance the sustainability of coastal systems, management strategies will also need to address this challenge, focusing on the drivers that are dominant at each section of coast. Global warming through the twentieth century has caused a series of changes with important implications for coastal areas. These include rising temperatures, rising sea level, increasing CO2 concentrations with an associated reduction in seawater pH, and more intense precipitation on average.

  11. Influence of the human reliability in the assessment of the impact on the risk of changes of CLO

    International Nuclear Information System (INIS)

    Martorell, P.; Martorell, S.; Marton, I.; Saiz, M.

    2014-01-01

    Treatment and study of epistemic uncertainties is of special importance in the application of the analysis of probabilistic security to informed decision-making in risk, as points out the guide regulatory 1,174 [1] (Regulatory Guide 1,174, RG1.174). Specifically, the RG 1.177 [2] details of the impact on risk assessment concerning changes in the technical operating specifications (ETF). Based on the framework defined by such regulatory guides, will be assessed the effect of uncertainties epistemic associated with the analysis of human reliability in the context of the limit conditions of operation. As an example of application, will be held a sensitivity study of the time of inoperability Completion Time, the Residual heat removal system. (Author)

  12. About water chemistry influence on equipment reliability of NPP with RBMK-1000

    International Nuclear Information System (INIS)

    Berezina, I.G.; Styazhkin, P.S.; Kritskij, V.G.

    2001-01-01

    In the paper the experience of a quantitative valuation of coolant quality influence on a reliability of some equipment elements of NPP with RBMK-1000 is offered. The choice is made of coolant quality integral parameter. The connection between indices values of coolant quality and reliability of major elements of circulation circuit equipment (including fuel claddings) is established. The reliability improvement of equipment elements operation is supported by high water chemistry quality. (orig.)

  13. Climate change and indicators of probable shifts in the consumption portfolios of dryland farmers in Sub-Saharan Africa

    NARCIS (Netherlands)

    Amjath-Babu, T.S.; Krupnik, Timothy J.; Aravindakshan, Sreejith; Arshad, Muhammad; Kaechele, Harald

    2016-01-01

    Several studies estimate the immediate impact of climate change on agricultural societies in terms of changes in crop yields or farm income, though few studies concentrate on the immediate secondary consequences of climate change. This synthetic analysis uses a set of indicators to assess the

  14. Intra- and interobserver reliability of quantitative ultrasound measurement of the plantar fascia.

    Science.gov (United States)

    Rathleff, Michael Skovdal; Moelgaard, Carsten; Lykkegaard Olesen, Jens

    2011-01-01

    To determine intra- and interobserver reliability and measurement precision of sonographic assessment of plantar fascia thickness when using one, the mean of two, or the mean of three measurements. Two experienced observers scanned 20 healthy subjects twice with 60 minutes between test and retest. A GE LOGIQe ultrasound scanner was used in the study. The built-in software in the scanner was used to measure the thickness of the plantar fascia (PF). Reliability was calculated using intraclass correlation coefficient (ICC) and limits of agreement (LOA). Intraobserver reliability (ICC) using one measurement was 0.50 for one observer and 0.52 for the other, and using the mean of three measurements intraobserver reliability increased up to 0.77 and 0.67, respectively. Interobserver reliability (ICC) when using one measurement was 0.62 and increased to 0.82 when using the average of three measurements. LOA showed that when using the average of three measurements, LOA decreased to 0.6 mm, corresponding to 17.5% of the mean thickness of the PF. The results showed that reliability increases when using the mean of three measurements compared with one. Limits of agreement based on intratester reliability shows that changes in thickness that are larger than 0.6 mm can be considered actual changes in thickness and not a result of measurement error. Copyright © 2011 Wiley Periodicals, Inc.

  15. Which is the most useful patient-reported outcome in femoroacetabular impingement? Test-retest reliability of six questionnaires.

    Science.gov (United States)

    Hinman, Rana S; Dobson, Fiona; Takla, Amir; O'Donnell, John; Bennell, Kim L

    2014-03-01

    The most reliable patient-reported outcomes (PROs) for people with femoroacetabular impingement (FAI) is unknown because there have been no direct comparisons of questionnaires. Thus, the aim was to evaluate the test-retest reliability of six existing PROs in a single cohort of young active people with hip/groin pain consistent with a clinical diagnosis of FAI. Young adults with clinical FAI completed six PRO questionnaires on two occasions, 1-2 weeks apart. The PROs were modified Harris Hip Score, Hip dysfunction and Osteoarthritis Score, Hip Outcome Score, Non-Arthritic Hip Score, International Hip Outcome Tool, Copenhagen Hip and Groin Outcome Score. 30 young adults (mean age 24 years, SD 4 years, range 18-30 years; 15 men) with stable symptoms participated. Intraclass correlation coefficient(3,1) values ranged from 0.73 to 0.93 (95% CI 0.38 to 0.98) indicating that most questionnaires reached minimal reliability benchmarks. Measurement error at the individual level was quite large for most questionnaires (minimal detectable change (MDC95) 12.4-35.6, 95% CI 8.7 to 54.0). In contrast, measurement error at the group level was quite small for most questionnaires (MDC95 2.2-7.3, 95% CI 1.6 to 11). The majority of the questionnaires were reliable and precise enough for use at the group level. Samples of only 23-30 individuals were required to achieve acceptable measurement variation at the group level. Further direct comparisons of these questionnaires are required to assess other measurement properties such as validity, responsiveness and meaningful change in young people with FAI.

  16. 76 FR 23171 - Electric Reliability Organization Interpretations of Interconnection Reliability Operations and...

    Science.gov (United States)

    2011-04-26

    ... Reliability Standards for the Bulk-Power System, Order No. 693, FERC Stats. & Regs. ] 31,242, order on reh'g...-Power System reliability may request an interpretation of a Reliability Standard.\\7\\ The ERO's standards... information in its reliability assessments. The Reliability Coordinator must monitor Bulk Electric System...

  17. Memorial Hermann: high reliability from board to bedside.

    Science.gov (United States)

    Shabot, M Michael; Monroe, Douglas; Inurria, Juan; Garbade, Debbi; France, Anne-Claire

    2013-06-01

    In 2006 the Memorial Hermann Health System (MHHS), which includes 12 hospitals, began applying principles embraced by high reliability organizations (HROs). Three factors support its HRO journey: (1) aligned organizational structure with transparent management systems and compressed reporting processes; (2) Robust Process Improvement (RPI) with high-reliability interventions; and (3) cultural establishment, sustainment, and evolution. The Quality and Safety strategic plan contains three domains, each with a specific set of measures that provide goals for performance: (1) "Clinical Excellence;" (2) "Do No Harm;" and (3) "Saving Lives," as measured by the Serious Safety Event rate. MHHS uses a uniform approach to performance improvement--RPI, which includes Six Sigma, Lean, and change management, to solve difficult safety and quality problems. The 9 acute care hospitals provide multiple opportunities to integrate high-reliability interventions and best practices across MHHS. For example, MHHS partnered with the Joint Commission Center for Transforming Healthcare in its inaugural project to establish reliable hand hygiene behaviors, which improved MHHS's average hand hygiene compliance rate from 44% to 92% currently. Soon after compliance exceeded 85% at all 12 hospitals, the average rate of central line-associated bloodstream and ventilator-associated pneumonias decreased to essentially zero. MHHS's size and diversity require a disciplined approach to performance improvement and systemwide achievement of measurable success. The most significant cultural change at MHHS has been the expectation for 100% compliance with evidence-based quality measures and 0% incidence of patient harm.

  18. Reliability and accuracy of Crystaleye spectrophotometric system.

    Science.gov (United States)

    Chen, Li; Tan, Jian Guo; Zhou, Jian Feng; Yang, Xu; Du, Yang; Wang, Fang Ping

    2010-01-01

    to develop an in vitro shade-measuring model to evaluate the reliability and accuracy of the Crystaleye spectrophotometric system, a newly developed spectrophotometer. four shade guides, VITA Classical, VITA 3D-Master, Chromascop and Vintage Halo NCC, were measured with the Crystaleye spectrophotometer in a standardised model, ten times for 107 shade tabs. The shade-matching results and the CIE L*a*b* values of the cervical, body and incisal regions for each measurement were automatically analysed using the supporting software. Reliability and accuracy were calculated for each shade tab both in percentage and in colour difference (ΔE). Difference was analysed by one-way ANOVA in the cervical, body and incisal regions. range of reliability was 88.81% to 98.97% and 0.13 to 0.24 ΔE units, and that of accuracy was 44.05% to 91.25% and 1.03 to 1.89 ΔE units. Significant differences in reliability and accuracy were found between the body region and the cervical and incisal regions. Comparisons made among regions and shade guides revealed that evaluation in ΔE was prone to disclose the differences. measurements with the Crystaleye spectrophotometer had similar, high reliability in different shade guides and regions, indicating predictable repeated measurements. Accuracy in the body region was high and less variable compared with the cervical and incisal regions.

  19. Reliability and validity of the workplace social distance scale.

    Science.gov (United States)

    Yoshii, Hatsumi; Mandai, Nozomu; Saito, Hidemitsu; Akazawa, Kouhei

    2014-10-29

    Self-stigma, defined by a negative attitude toward oneself combined with the consciousness of being a target of prejudice, is a critical problem for psychiatric patients. Self-stigma studies among psychiatric patients have indicated that high stigma is predictive of detrimental effects such as the delay of treatment and decreases in social participation in patients, and levels of self-stigma should be statistically evaluated. In this study, we developed the Workplace Social Distance Scale (WSDS), rephrasing the eight items of the Japanese version of the Social Distance Scale (SDSJ) to apply to the work setting in Japan. We examined the reliability and validity of the WSDS among 83 psychiatric patients. Factor analysis extracted three factors from the scale items: "work relations," "shallow relationships," and "employment." These factors are similar to the assessment factors of the SDSJ. Cronbach's alpha coefficient for the WSDS was 0.753. The split-half reliability for the WSDS was 0.801, indicating significant correlations. In addition, the WSDS was significantly correlated with the SDSJ. These findings suggest that the WSDS represents an approximation of self-stigma in the workplace among psychiatric patients. Our study assessed the reliability and validity of the WSDS for measuring self-stigma in Japan. Future studies should investigate the reliability and validity of the scale in other countries.

  20. Reliability, Validity, and Minimal Detectable Change of Balance Evaluation Systems Test and Its Short Versions in Older Cancer Survivors: A Pilot Study.

    Science.gov (United States)

    Huang, Min H; Miller, Kara; Smith, Kristin; Fredrickson, Kayle; Shilling, Tracy

    2016-01-01

    Cancer is primarily a disease of older adults. About 77% of all cancers are diagnosed in persons aged 55 years and older. Cancer and its treatment can cause diverse sequelae impacting body systems underlying balance control. No study has examined the psychometric properties of balance assessment tools in older cancer survivors, presenting a significant challenge in the selection of outcome measures for clinicians treating this fast-growing population. This study aimed to determine the reliability, validity, and minimal detectable change (MDC) of the Balance Evaluation System Test (BESTest), Mini-Balance Evaluation Systems Test (Mini-BESTest), and Brief-Balance Evaluation Systems Test (Brief-BESTest) in community-dwelling older cancer survivors. This study was a cross-sectional design. Twenty breast and 8 prostate cancer survivors participated [age (SD) = 68.4 (8.13) years]. The BESTest and Activity-specific Balance Confidence (ABC) Scale were administered during the first session. Scores of Mini-BESTest and Brief-BESTest were extracted on the basis of the scores of BESTest. The BESTest was repeated within 1 to 2 weeks by the same rater to determine the test-retest reliability. For the analysis of the inter-rater reliability, 21 participants were randomly selected to be evaluated by 2 raters. A primary rater administered the test. The 2 raters independently and concurrently scored the performance of the participants. Each rater recorded the ratings separately on the scoring sheet. No discussion among the raters was allowed throughout the testing. Intraclass correlation coefficients (ICCs), standard error of measurement, minimal detectable change (MDC), and Bland-Altman plots were calculated. Concurrent validity of these balance tests with the ABC Scale was examined using the Spearman correlation. The BESTest, Mini-BESTest, and Brief-BESTest had high test-retest (ICC = 0.90-0.94) and interrater reliability (ICC = 0.86-0.96), small standard error of measurement (0