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Sample records for subscales improved reliability

  1. Examining unidimensionality and improving reliability for the eight subscales of the SF-36 in opioid-dependent patients using Rasch analysis.

    Science.gov (United States)

    Hsiao, Yu-Yu; Shih, Ching-Lin; Yu, Wan-Hui; Hsieh, Cheng-Hsi; Hsieh, Ching-Lin

    2015-02-01

    The Medical Outcome Study Short Form 36 (SF-36) is one of the most commonly used questionnaires for monitoring the Health-Related Quality of Life (HRQOL) of opioid-dependent patients. However, the unidimensionality and reliability of the SF-36 have not been verified in opioid-dependent patients. The aim of this study was to examine the unidimensionality and to improve the test reliability of the SF-36 for use in opioid-dependent patients. A total of 583 opioid-dependent patients were recruited in the study. Unidimensionality was examined by conducting unidimensional Rasch analysis. Item fit statistics and principle component analysis were used to check the item-model fit in each of the eight subscales of the SF-36. Reliability was evaluated by applying both unidimensional and multidimensional Rasch analyses. After three misfitting items were excluded, the remaining items of each subscale in the SF-36 represented a single construct. The test reliabilities (0.80-0.87) yielded by the multidimensional approach were much higher than those (0.68-0.82) produced by the unidimensional approach. The remaining 32 items of the SF-36 are appropriate for evaluating the HRQOL in opioid-dependent patients in terms of unidimensionality. Additionally, the test scores produced by the multidimensional approach were more accurate than those obtained by the unidimensional approach.

  2. Measuring Neuroticism in Nepali: Reliability and Validity of the Neuroticism Subscale of the Eysenck Personality Questionnaire.

    Science.gov (United States)

    Manandhar, K; Risal, A; Linde, M; Koju, R; Steiner, T J; Holen, A

    2015-01-01

    The Neuroticism subscale of the Eysenck Personality Questionnaire Revised Short Form (12 items) (EPQRS-N) has proven to be a reliable and valid measure in multiple languages. To develop a single-factor Nepali-language version of the EPQRS-N for use in the adult population of Nepal. The original English version of EPQRS-N was translated into Nepali using a forward-backward translation protocol. The first set of translated items was modified after testing by factor analysis with principal component extraction in an outpatient sample. Items with low factor correlations or poor semantic consistencies were reworded to fit the gist of the original items in a Nepali cultural context; the revised version was then tested in a representative random sample from the general population. Again, the same statistical procedures were applied. The first trial gave three factors. Based on the factor distribution of the items or their semantic quality, five were reworded. In the second trial, a two-factor solution emerged; the second factor had only one item with high correlation, which also had modest correlation with the first factor. Accordingly, a forced one-factor solution was chosen. This gave an internal consistency (Cronbach's alpha) of 0.80, with item-to-factor correlations from 0.40 to 0.73, and item-to-sum correlations from 0.31 to 0.61. The final Nepali version of EPQRS-N achieved satisfactory internal consistency. The item distribution coincided with the original English version, providing acceptable construct validity. It is psychometrically adequate for use in capturing the personality trait of neuroticism, and has broad applicability to the adult population of Nepal because of the diversity of the participant samples in which it was developed.

  3. [Turkish expressive and receptive language test: I. Standardization, reliability and validity study of the receptive vocabulary sub-scale].

    Science.gov (United States)

    Kazak Berument, Sibel; Güven, Ayşe Gül

    2013-01-01

    A reliable, valid and original test to assess the receptive vocabulary skills of children in Turkey was not available. Thus, the purpose of the current study was to develop a receptive vocabulary test for Turkish children based on the Turkish language. For the Receptive Vocabulary Sub-Scale (TIFALDI-RT) 242 concrete and abstract words were chosen from word frequency lists and a comprehensive Turkish Dictionary. Pilot data were collected from 648 children aged 2 to 13 from Ankara, and norm data were collected from a nationally representative sample of 3755 children. Item analysis (item difficulty, discrimination and distractor) was carried out on the pilot data and based on the results, the total item number was reduced to 157. Further, three parameter item analyses (IRT) were carried out on the norm data by using BILOG-MG (SSI, 2002), and the results indicated that the TIFALDI Receptive Vocabulary Sub-Scale could be reduced to 104 items to assess 2 to 12 year-old children's receptive vocabulary. Test-retest and internal consistency reliabilities were calculated for the whole sample and age groups separately, and all the coefficients were high. For the validity, the relationship between the WISC-R and Ankara Developmental Screening Inventory (AGTE) and Receptive Vocabulary Sub-Scale were investigated. Once again, the TIFALDI Receptive Vocabulary Sub-Scale scores were found to be significantly related to WISC-R and AGTE scores. The TIFALDI Receptive Vocabulary Sub-Scale was developed on the basis of the Turkish Language and norm data were collected from a nationally representative sample. The TIFALDI-RT also had a high reliability and validity. Thus, the TIFALDI-RT can be used to assess 2 to 12 year-old children's receptive vocabulary skills.

  4. Construct Validity and Reliability of the SARA Gait and Posture Sub-scale in Early Onset Ataxia

    Directory of Open Access Journals (Sweden)

    Tjitske F. Lawerman

    2017-12-01

    Full Text Available Aim: In children, gait and posture assessment provides a crucial marker for the early characterization, surveillance and treatment evaluation of early onset ataxia (EOA. For reliable data entry of studies targeting at gait and posture improvement, uniform quantitative biomarkers are necessary. Until now, the pediatric test construct of gait and posture scores of the Scale for Assessment and Rating of Ataxia sub-scale (SARA is still unclear. In the present study, we aimed to validate the construct validity and reliability of the pediatric (SARAGAIT/POSTURE sub-scale.Methods: We included 28 EOA patients [15.5 (6–34 years; median (range]. For inter-observer reliability, we determined the ICC on EOA SARAGAIT/POSTURE sub-scores by three independent pediatric neurologists. For convergent validity, we associated SARAGAIT/POSTURE sub-scores with: (1 Ataxic gait Severity Measurement by Klockgether (ASMK; dynamic balance, (2 Pediatric Balance Scale (PBS; static balance, (3 Gross Motor Function Classification Scale -extended and revised version (GMFCS-E&R, (4 SARA-kinetic scores (SARAKINETIC; kinetic function of the upper and lower limbs, (5 Archimedes Spiral (AS; kinetic function of the upper limbs, and (6 total SARA scores (SARATOTAL; i.e., summed SARAGAIT/POSTURE, SARAKINETIC, and SARASPEECH sub-scores. For discriminant validity, we investigated whether EOA co-morbidity factors (myopathy and myoclonus could influence SARAGAIT/POSTURE sub-scores.Results: The inter-observer agreement (ICC on EOA SARAGAIT/POSTURE sub-scores was high (0.97. SARAGAIT/POSTURE was strongly correlated with the other ataxia and functional scales [ASMK (rs = -0.819; p < 0.001; PBS (rs = -0.943; p < 0.001; GMFCS-E&R (rs = -0.862; p < 0.001; SARAKINETIC (rs = 0.726; p < 0.001; AS (rs = 0.609; p = 0.002; and SARATOTAL (rs = 0.935; p < 0.001]. Comorbid myopathy influenced SARAGAIT/POSTURE scores by concurrent muscle weakness, whereas comorbid myoclonus predominantly influenced

  5. Improving machinery reliability

    CERN Document Server

    Bloch, Heinz P

    1998-01-01

    This totally revised, updated and expanded edition provides proven techniques and procedures that extend machinery life, reduce maintenance costs, and achieve optimum machinery reliability. This essential text clearly describes the reliability improvement and failure avoidance steps practiced by best-of-class process plants in the U.S. and Europe.

  6. Improving Power Converter Reliability

    DEFF Research Database (Denmark)

    Ghimire, Pramod; de Vega, Angel Ruiz; Beczkowski, Szymon

    2014-01-01

    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...... 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...

  7. Improving Software Reliability Forecasting

    NARCIS (Netherlands)

    Burtsy, Bernard; Albeanu, Grigore; Boros, Dragos N.; Popentiu, Florin; Nicola, V.F.

    1996-01-01

    This work investigates some methods for software reliability forecasting. A supermodel is presented as a suited tool for prediction of reliability in software project development. Also, times series forecasting for cumulative interfailure time is proposed and illustrated.

  8. Construct Validity and Reliability of the SARA Gait and Posture Sub-scale in Early Onset Ataxia

    NARCIS (Netherlands)

    Lawerman, Tjitske F.; Brandsma, Rick; Verbeek, Renate J.; van der Hoeven, Johannes H.; Lunsing, Roelineke J.; Kremer, Hubertus P. H.; Sival, Deborah A.

    2017-01-01

    Aim: In children, gait and posture assessment provides a crucial marker for the early characterization, surveillance and treatment evaluation of early onset ataxia (EOA). For reliable data entry of studies targeting at gait and posture improvement, uniform quantitative biomarkers are necessary.

  9. Evidence That the Clinical Impairment Assessment (CIA) Subscales Should Not Be Scored: Bifactor Modelling, Reliability, and Validity in Clinical and Community Samples.

    Science.gov (United States)

    Raykos, Bronwyn; Erceg-Hurn, David; McEvoy, Peter; Byrne, Susan M

    2017-09-01

    The Clinical Impairment Assessment (CIA 3.0) is the most widely used instrument assessing psychosocial impairment secondary to eating disorder symptoms. However, there is conflicting advice regarding the dimensionality and optimal method of scoring the CIA. We sought to resolve this confusion by conducting a comprehensive factor analytic study of the CIA in a community sample ( N = 301) and clinical sample comprising patients with a diagnosed eating disorder ( N = 209). Convergent and discriminant validity were also assessed. The CIA and measures of eating disorder symptoms were administered to both samples. Factor analyses indicated there is a general impairment factor underlying all items on the CIA that is reliably measured by the CIA Global score. CIA Global demonstrated good convergent and discriminant validity. CIA Global is a reliable and valid measure of psychosocial impairment secondary to eating disorder symptoms; however, subscale scores should not be computed.

  10. Trans-adapted, reliability, and validity of children fear survey schedule-dental subscale in Bahasa Indonesia

    Directory of Open Access Journals (Sweden)

    Arlette Suzy

    2015-03-01

    Full Text Available Background: The most frequently used measuring instrument for determination of dental fear in children nowadays is the children’s fear survey schedule-dental scale (CFSS-DS. Purpose: The purpose of this study was to explore the reliability and validity of the scale with Indonesian trans adapted version of the scale, thus the scale can be reliable to be used in other similar research in Indonesia. Methods: Total of 113 participants, who were parent’s 3 to 12 years old children. Children were divided into two age groups, group I 3-6 year old (83 children and group II 7-12 year old (30 children. Eighty three children from the first group were divided into first dental visit group (30 children and non first dental visit group (53 children. Test-retest approach was applied to 30 first dental visit children aged 3-6 year old. Original scale was translated to Indonesian language. Result: The result showed the high value of the Cronbach’s coefficient of internal consistency α=0.956. Three factors were extracted by screen test method with Eigen values higher than 1, which explained 93.05% variance of results. Conclusion: CFSS-DS scale is reliable and valid psychometric instrument for dental fear evaluation in children in Bahasa Indonesia. The differences between this study and those of others may appear due to many factors. Normal 0 false false false EN-US X-NONE X-NONE

  11. Improved Availability Processes from Reliability

    Directory of Open Access Journals (Sweden)

    Henrry Ricardo-Cabrera

    2015-12-01

    Full Text Available This research was conducted in the industry, “Cementos Cienfuegos S.A.”, its main objective was to implement a method for improving the technical availability of the production processes. The method described uses classical analytical systems as a tool to improve the work of the operators of industrial facilities using checklists developed from the identification of the contribution of the unavailability of equipment to the failure of the technological system. Examples of application are the results in the cement technology systems, made on the basis of the reliability of the components of technological systems, specifically the process of raw materials. As a result of improvements in technical implementation process availability are obtained and, therefore, an increasing efficiency. The extension of this work can ensure the improvement of the general availability of the industry.

  12. Improving the Reliability of IPM

    CERN Document Server

    Giacomini, T

    2005-01-01

    IPMs measure in a non-destructive way the profile of ion beams independent whether the beam is bunched or not. Our application is the heavy ion synchrotron SIS, which can accelerate ions with a large variety of different masses and charges. The IPM is used to obtain information about the beam matching, the electron cooling and to support for any kind of machine experiments. To ensure reliable function and to increase the data accuracy we executed some important mechanical improvements. The resistive e-field plates were replaced by discrete electrodes. We designed a new MCP-Phosphor-screen assembly of rectangular shape and large active area and in addition a module with a filament mounted in meander shape to monitor the degradation of the MCPs. The whole device was planned with respect of high field uniformity and small mechanical dimensions at a large clearance for the beam.

  13. Improved reliability of power modules

    DEFF Research Database (Denmark)

    Baker, Nick; Liserre, Marco; Dupont, Laurent

    2014-01-01

    environments that challenge the reliability aspects of power electronic techniques. For example, increasingly thermally stressful environments are seen in applications such as electric vehicles, where ambient temperatures under the hood exceed 150 °C, while some wind turbine applications can place large...... temperature cycling conditions on the system. On the other hand, safety requirements in the aerospace and automotive industries place rigorous demands on reliability....

  14. Functional autonomy measurement system: development of a social subscale.

    Science.gov (United States)

    Pinsonnault, E; Desrosiers, J; Dubuc, N; Kalfat, H; Colvez, A; Delli-Colli, N

    2003-01-01

    The purpose of this study was to develop a subscale assessing social functioning for the functional autonomy measurement system (SMAF). The development of this new dimension was based on consultations (focus groups and nominal groups) of experts from different health care disciplines in Quebec, Canada, and France. Two interrater reliability studies were carried out with older people presenting a loss of functional autonomy and living either in an institution or at home. With the focus groups, the experts clarified the definition of social functioning and identified the factors involved. The nominal groups were used to construct a subscale composed of six items. The results of the first interrater reliability study showed a mean agreement percentage of 60% for the subscale and an intraclass correlation coefficient (ICC) of 0.70 (CI: 0.57-0.80). The results of the second interrater reliability study showed higher coefficients with an agreement percentage of 74% for the subscale and an ICC of 0.83 (CI: 0.61-0.93). These preliminary results demonstrate that the new social functioning subscale has good reliability, but more studies are needed to show its validity. The new SMAF, including the social functioning subscale, should help clinicians and researchers to obtain a comprehensive profile of functional autonomy. It could also contribute to the improvement of health care for older people.

  15. Reliability Validation and Improvement Framework

    Science.gov (United States)

    2012-11-01

    of failure occurrences of many reliability predictions, taking on the form of fault tree analysis (FTA), and failure mode and effects analysis ( FMEA ...and its potential negative impact. As the system design progresses, fault tree analysis (FTA) and failure mode and effect analysis ( FMEA ) are used to...predictions such as Mean Time To Failure (MTTF) to FHA, fault impact such as FMEA , and FTA [Rugina 2008, Joshi 2007, Bozzano 2009]. • A Behavior

  16. Relating Unidimensional IRT Parameters to a Multidimensional Response Space: A Review of Two Alternative Projection IRT Models for Scoring Subscales

    Science.gov (United States)

    Kahraman, Nilufer; Thompson, Tony

    2011-01-01

    A practical concern for many existing tests is that subscore test lengths are too short to provide reliable and meaningful measurement. A possible method of improving the subscale reliability and validity would be to make use of collateral information provided by items from other subscales of the same test. To this end, the purpose of this article…

  17. Reliability-How to Quantify and Improve?

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 5; Issue 5. Reliability - How to Quantify and Improve? - Improving the Health of Products. N K Srinivasan. General Article Volume 5 Issue 5 May 2000 pp 55-63. Fulltext. Click here to view fulltext PDF. Permanent link:

  18. Heroic Reliability Improvement in Manned Space Systems

    Science.gov (United States)

    Jones, Harry W.

    2017-01-01

    System reliability can be significantly improved by a strong continued effort to identify and remove all the causes of actual failures. Newly designed systems often have unexpected high failure rates which can be reduced by successive design improvements until the final operational system has an acceptable failure rate. There are many causes of failures and many ways to remove them. New systems may have poor specifications, design errors, or mistaken operations concepts. Correcting unexpected problems as they occur can produce large early gains in reliability. Improved technology in materials, components, and design approaches can increase reliability. The reliability growth is achieved by repeatedly operating the system until it fails, identifying the failure cause, and fixing the problem. The failure rate reduction that can be obtained depends on the number and the failure rates of the correctable failures. Under the strong assumption that the failure causes can be removed, the decline in overall failure rate can be predicted. If a failure occurs at the rate of lambda per unit time, the expected time before the failure occurs and can be corrected is 1/lambda, the Mean Time Before Failure (MTBF). Finding and fixing a less frequent failure with the rate of lambda/2 per unit time requires twice as long, time of 1/(2 lambda). Cutting the failure rate in half requires doubling the test and redesign time and finding and eliminating the failure causes.Reducing the failure rate significantly requires a heroic reliability improvement effort.

  19. Leveraging Code Comments to Improve Software Reliability

    Science.gov (United States)

    Tan, Lin

    2009-01-01

    Commenting source code has long been a common practice in software development. This thesis, consisting of three pieces of work, made novel use of the code comments written in natural language to improve software reliability. Our solution combines Natural Language Processing (NLP), Machine Learning, Statistics, and Program Analysis techniques to…

  20. Improvement of the reliability on nondestructive inspection

    Energy Technology Data Exchange (ETDEWEB)

    Song, Sung Jin; Kim, Young H. [Sungkyunkwan Univ., Suwon (Korea, Republic of); Lee, Hyang Beom [Soongsil Univ., Seoul (Korea, Republic of); Shin, Young Kil [Kunsan National Univ., Gunsan (Korea, Republic of); Jung, Hyun Jo [Wonkwang Univ., Iksan (Korea, Republic of); Park, Ik Keun; Park, Eun Soo [Seoul Nationl Univ., Seoul (Korea, Republic of)

    2002-03-15

    Retaining reliabilities of nondestructive testing is essential for the life-time maintenance of Nuclear Power Plant. The nondestructive testing methods which are frequently used in the Nuclear Power Plant are eddy current testing for the inspection of steam generator tubes and ultrasonic testing for the inspection of weldments. In order to improve reliabilities of ultrasonic testing and eddy current testing, the subjects carried out in this study are as follows : development of BEM analysis technique for ECT of SG tube, development of neural network technique for the intelligent analysis of ECT flaw signals of SG tubes, development of RFECT technology for the inspection of SG tube, FEM analysis of ultrasonic scattering field, evaluation of statistical reliability of PD-RR test of ultrasonic testing and development of multi-Gaussian beam modeling technique to predict accurate signal of signal beam ultrasonic testing with the efficiency in calculation time.

  1. SOFC Systems with Improved Reliability and Endurance

    Energy Technology Data Exchange (ETDEWEB)

    Ghezel-Ayagh, Hossein [Fuelcell Energy, Incorporated, Danbury, CT (United States)

    2015-12-31

    The overall goal of this U.S. Department of Energy (DOE) sponsored project was the development of Solid Oxide Fuel Cell (SOFC) technology suitable for ultra-efficient central power generation systems utilizing coal and natural gas fuels and featuring greater than 90% carbon dioxide capture. The specific technical objective of this project was to demonstrate, via analyses and testing, progress towards adequate stack life (≥ 4 years) and stack performance stability (degradation rate ≤ 0.2% per 1000 hours) in a low-cost SOFC stack design. This final technical report summarizes the progress made during the project period of 27 months. Significant progress was made in the areas of cell and stack technology development, stack module development, sub-scale module tests, and Proof-of-Concept Module unit design, fabrication and testing. The work focused on cell and stack materials and designs, balance-of-plant improvements, and performance evaluation covering operating conditions and fuel compositions anticipated for commercially-deployed systems. In support of performance evaluation under commercial conditions, this work included the design, fabrication, siting, commissioning, and operation of a ≥ 50 kWe proof-of-concept module (PCM) power plant, based upon SOFC cell and stack technology developed to date by FuelCell Energy, Inc. (FCE) under the Office of Fossil Energy’s Solid Oxide Fuel Cells program. The PCM system was operated for at least 1000 hours on natural gas fuel at FCE’s facility. The factory cost of the SOFC stack was estimated to be at or below the DOE’s high-volume production cost target (2011 $).

  2. Advanced solutions for operational reliability improvements

    Energy Technology Data Exchange (ETDEWEB)

    Holmberg, K. [VTT Manufacturing Technology, Espoo (Finland)

    1997-12-31

    A great number of new technical tools are today developed for improved operational reliability of machines and industrial equipment. Examples of such techniques and tools recently developed at the Technical Research Centre of Finland (VTT) are: metallographic approach for steam-piping lifetime estimation, an expert system AURORA for corrosion prediction and material selection, an automatic image-processing-based on-line wear particle analysis system, microsensors for condition monitoring, a condition monitoring and expert system, CEPDIA, for the diagnosis of centrifugal pumps, a machine tool analysis and diagnostic expert system, non-leakage magnetic fluid seals with extended lifetime and diamond-like surface coatings on components with decreased friction and wear properties. A hyperbook-supported holistic approach to problem solving in maintenance and reliability engineering has been developed to help the user achieve a holistic understanding of the problem and its relationships, to navigate among the several technical tools and methods available, and to find those suitable for his application. (orig.)

  3. Software reliability: Failures, consequences and improvement ...

    African Journals Online (AJOL)

    Software reliability is one of a number of aspects of computer software which can be taken into consideration when determining the quality of the software. Software reliability is an important factor affecting system performance. It differs from hardware reliability in that it reflects the design perfection rather than manufacturing ...

  4. software reliability: failures, consequences and improvement

    African Journals Online (AJOL)

    BARTH EKWUEME

    2009-07-16

    Jul 16, 2009 ... Software reliability is one of a number of aspects of computer software which can be taken into consideration when determining the quality of the software. Software reliability is an important factor affecting system performance. It differs from hardware reliability in that it reflects the design perfection rather ...

  5. Reliability - How to Quantify and Improve?

    Indian Academy of Sciences (India)

    Societies, particularly the industrialised ones depend largely on proper functioning of several equipment - mechanical, electrical and electronic - for industries, farms and even homes. The reliability of a water pump or electric motor driving the pump or a tractor is of great concern to a farmer. Industries pay much attention to ...

  6. Sonar Transducer Reliability Improvement Program FY 80.

    Science.gov (United States)

    1980-04-01

    available- as a potentially grand reliability experiment. 7. Clos er interdisciplinary cooperation is in order - scientisits need to address practical...Vogelsong 271 Catalina Blvd Code 316, C. LeBlanc San Diego, CA 92152 Code 316, C. Olds ATTN: Code 712, D.L. Carson Code 342, T. Suzi Code 712, J

  7. Item-level and subscale-level factoring of Biggs' Learning Process Questionnaire (LPQ) in a mainland Chinese sample.

    Science.gov (United States)

    Sachs, J; Gao, L

    2000-09-01

    The learning process questionnaire (LPQ) has been the source of intensive cross-cultural study. However, an item-level factor analysis of all the LPQ items simultaneously has never been reported. Rather, items within each subscale have been factor analysed to establish subscale unidimensionality and justify the use of composite subscale scores. It was of major interest to see if the six logically constructed items groups of the LPQ would be supported by empirical evidence. Additionally, it was of interest to compare the consistency of the reliability and correlational structure of the LPQ subscales in our study with those of previous cross-cultural studies. Confirmatory factor analysis was used to fit the six-factor item level model and to fit five representative subscale level factor models. A total of 1070 students between the ages of 15 to 18 years was drawn from a representative selection of 29 classes from within 15 secondary schools in Guangzhou, China. Males and females were almost equally represented. The six-factor item level model of the LPQ seemed to fit reasonably well, thus supporting the six dimensional structure of the LPQ and justifying the use of composite subscale scores for each LPQ dimension. However, the reliability of many of these subscales was low. Furthermore, only two subscale-level factor models showed marginally acceptable fit. Substantive considerations supported an oblique three-factor model. Because the LPQ subscales often show low internal consistency reliability, experimental and correlational studies that have used these subscales as dependent measures have been disappointing. It is suggested that some LPQ items should be revised and other items added to improve the inventory's overall psychometric properties.

  8. Assessment of power reliability and improvement potential by using ...

    African Journals Online (AJOL)

    This paper presents the use of smart reclosers for improving reliability of a distribution system of one of the major cities of Ethiopia. As frequent power interruptions are posing a huge problem to the life of the people and the economy, finding a solution to the problem is very essential. Electric reliability has affected social well ...

  9. Applying franchising principles to improving water and sanitation services reliability

    CSIR Research Space (South Africa)

    Wall, K

    2008-11-01

    Full Text Available to improving water and sanitation services reliability K WALL CSIR Built Environment PO Box 395, Pretoria, 0001, South Africa Email: kwall@csir.co.za ABSTRACT CSIR research has found that franchising partnerships could alleviate and address many... business, whereafter it supports and disciplines the business. See Figure 1. The key is the incentive, to franchisor and franchisee alike, to provide improved service consistency, reliability and quality control. (You know what you will be getting...

  10. Interobserver Reliability of the Berlin ARDS Definition and Strategies to Improve the Reliability of ARDS Diagnosis.

    Science.gov (United States)

    Sjoding, Michael W; Hofer, Timothy P; Co, Ivan; Courey, Anthony; Cooke, Colin R; Iwashyna, Theodore J

    2017-12-14

    Failure to reliably diagnose ARDS may be a major driver of negative clinical trials and underrecognition and treatment in clinical practice. We sought to examine the interobserver reliability of the Berlin ARDS definition and examine strategies for improving the reliability of ARDS diagnosis. Two hundred five patients with hypoxic respiratory failure from four ICUs were reviewed independently by three clinicians, who evaluated whether patients had ARDS, the diagnostic confidence of the reviewers, whether patients met individual ARDS criteria, and the time when criteria were met. Interobserver reliability of an ARDS diagnosis was "moderate" (kappa = 0.50; 95% CI, 0.40-0.59). Sixty-seven percent of diagnostic disagreements between clinicians reviewing the same patient was explained by differences in how chest imaging studies were interpreted, with other ARDS criteria contributing less (identification of ARDS risk factor, 15%; cardiac edema/volume overload exclusion, 7%). Combining the independent reviews of three clinicians can increase reliability to "substantial" (kappa = 0.75; 95% CI, 0.68-0.80). When a clinician diagnosed ARDS with "high confidence," all other clinicians agreed with the diagnosis in 72% of reviews. There was close agreement between clinicians about the time when a patient met all ARDS criteria if ARDS developed within the first 48 hours of hospitalization (median difference, 5 hours). The reliability of the Berlin ARDS definition is moderate, driven primarily by differences in chest imaging interpretation. Combining independent reviews by multiple clinicians or improving methods to identify bilateral infiltrates on chest imaging are important strategies for improving the reliability of ARDS diagnosis. Copyright © 2017 American College of Chest Physicians. All rights reserved.

  11. Designing incentive market mechanisms for improving restructured power system reliabilities

    DEFF Research Database (Denmark)

    Ding, Yi; Østergaard, Jacob; Wu, Qiuwei

    2011-01-01

    In a restructured power system, the monopoly generation utility is replaced by different electricity producers. There exists extreme price volatility caused by random failures by generation or/and transmission systems. In these cases, producers' profits can be much higher than those in the normal...... state. The reliability management of producers usually cannot be directly controlled by the system operators in a restructured power system. Producers may have no motivation to improve their reliabilities, which can result in serious system unreliability issues in the new environment. Incentive market...... mechanisms for improving the restructured power system reliabilities have been designed in this paper. In the proposed incentive mechanisms, penalty will be implemented on a producer if the failures of its generator(s) result in the variation of electricity prices. Incentive market mechanisms can motivate...

  12. On One Possibility to Improve Reliability of Magnetic Starter

    Directory of Open Access Journals (Sweden)

    V. A. Anishchenko

    2013-01-01

    Full Text Available The paper proposes and considers a possibility to improve an operational reliability of reversing magnetic starters by reservation of main and auxiliary contacts in accordance with majority-logic voter «two out of three».

  13. Reliability Improved Cooperative Communication over Wireless Sensor Networks

    Directory of Open Access Journals (Sweden)

    Zhuangbin Chen

    2017-10-01

    Full Text Available With the development of smart devices and connection technologies, Wireless Sensor Networks (WSNs are becoming increasingly intelligent. New or special functions can be obtained by receiving new versions of program codes to upgrade their software systems, forming the so-called smart Internet of Things (IoT. Due to the lossy property of wireless channels, data collection in WSNs still suffers from a long delay, high energy consumption, and many retransmissions. Thanks to wireless software-defined networks (WSDNs, software in sensors can now be updated to help them transmit data cooperatively, thereby achieving more reliable communication. In this paper, a Reliability Improved Cooperative Communication (RICC data collection scheme is proposed to improve the reliability of random-network-coding-based cooperative communications in multi-hop relay WSNs without reducing the network lifetime. In WSNs, sensors in different positions can have different numbers of packets to handle, resulting in the unbalanced energy consumption of the network. In particular, nodes in non-hotspot areas have up to 90% of their original energy remaining when the network dies. To efficiently use the residual energy, in RICC, high data transmission power is adopted in non-hotspot areas to achieve a higher reliability at the cost of large energy consumption, and relatively low transmission power is adopted in hotspot areas to maintain the long network lifetime. Therefore, high reliability and a long network lifetime can be obtained simultaneously. The simulation results show that compared with other scheme, RICC can reduce the end-to-end Message Fail delivering Ratio (MFR by 59.4%–62.8% under the same lifetime with a more balanced energy utilization.

  14. Grant Peer Review: Improving Inter-Rater Reliability with Training.

    Science.gov (United States)

    Sattler, David N; McKnight, Patrick E; Naney, Linda; Mathis, Randy

    2015-01-01

    This study developed and evaluated a brief training program for grant reviewers that aimed to increase inter-rater reliability, rating scale knowledge, and effort to read the grant review criteria. Enhancing reviewer training may improve the reliability and accuracy of research grant proposal scoring and funding recommendations. Seventy-five Public Health professors from U.S. research universities watched the training video we produced and assigned scores to the National Institutes of Health scoring criteria proposal summary descriptions. For both novice and experienced reviewers, the training video increased scoring accuracy (the percentage of scores that reflect the true rating scale values), inter-rater reliability, and the amount of time reading the review criteria compared to the no video condition. The increase in reliability for experienced reviewers is notable because it is commonly assumed that reviewers--especially those with experience--have good understanding of the grant review rating scale. The findings suggest that both experienced and novice reviewers who had not received the type of training developed in this study may not have appropriate understanding of the definitions and meaning for each value of the rating scale and that experienced reviewers may overestimate their knowledge of the rating scale. The results underscore the benefits of and need for specialized peer reviewer training.

  15. Improvement of Steam Generator Reliability for GEN-IV SFR

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Seong O; Kim Se Yun; Kim, Seok Hoon; Eoh, Jae Hyuk; Lee, Hyeong Yeon; Choi, Byung Seon

    2005-11-15

    The R and D items performed in this study were selected from the R and D task of ' Reliability improvement of Steam Generator' of GEN-IV SFR Component Design and BOP. Since this project deals with one of the most important issues for a GEN-IV SFR system, it needs to enhance the domestic technical backgrounds associated with the corresponding R and D items even for a very short period by 2005. This study provides the R and D results for i) Development of assessment methodology for dissimilar metal weld and ii) Development of multi-dimensional simulation methodology for a SWR event in a SFR steam generator.

  16. Improved reliability of residential heat pumps; Foerbaettrad driftsaekerhet hos villavaermepumpar

    Energy Technology Data Exchange (ETDEWEB)

    Haglund Stignor, Caroline; Larsson, Kristin; Jensen, Sara; Larsson, Johan; Berg, Johan; Lidbom, Peter; Rolfsman, Lennart

    2012-07-01

    Today, heat pump heating systems are common in Swedish single-family houses. Many owners are pleased with their installation, but statistics show that a certain number of heat pumps break every year, resulting in high costs for both insurance companies and owners. On behalf of Laensfoersaekringars Forskningsfond, SP Energy Technology has studied the cause of the most common failures for residential heat pumps. The objective of the study was to suggest what measures to be taken to reduce the number of failures, i.e. improving the reliability of heat pumps. The methods used were analysis of public failure statistics and sales statistics and interviews with heat pump manufacturers, installers, service representatives and assessors at Laensfoersaekringar. In addition, heat pump manuals have been examined and literature searches for various methods for durability tests have been performed. Based on the outcome from the interviews the most common failures were categorized by if they; 1. Could have been prevented by better operation and maintenance of the heat pump. 2. Caused by a poorly performed installation. 3. Could have been prevented if certain parameters had been measured, recorded and followed up. 4. Are due to poor quality of components or systems. However, the results show that many of the common failures fall into several different categories and therefore, different types of measures must be taken to improve the operational reliability of residential heat pumps. The interviews tell that failures often are caused by poor installation, neglected maintenance and surveillance, and poor quality of standard components or that components are used outside their declared operating range. The quality of the installations could be improved by increasing installers' knowledge about heat pumps and by requiring that an installation protocol shall be filled-in. It is also important that the owner of the heat pump performs the preventive maintenance recommended by the

  17. A3 Subscale Diffuser Test Article Design

    Science.gov (United States)

    Saunders, G. P.

    2009-01-01

    This paper gives a detailed description of the design of the A3 Subscale Diffuser Test (SDT) Article Design. The subscale diffuser is a geometrically accurate scale model of the A3 altitude rocket facility. It was designed and built to support the SDT risk mitigation project located at the E3 facility at Stennis Space Center, MS (SSC) supporting the design and construction of the A3 facility at SSC. The subscale test article is outfitted with a large array of instrumentation to support the design verification of the A3 facility. The mechanical design of the subscale diffuser and test instrumentation are described here

  18. Improving electronic sensor reliability by robust outlier screening.

    Science.gov (United States)

    Moreno-Lizaranzu, Manuel J; Cuesta, Federico

    2013-10-09

    Electronic sensors are widely used in different application areas, and in some of them, such as automotive or medical equipment, they must perform with an extremely low defect rate. Increasing reliability is paramount. Outlier detection algorithms are a key component in screening latent defects and decreasing the number of customer quality incidents (CQIs). This paper focuses on new spatial algorithms (Good Die in a Bad Cluster with Statistical Bins (GDBC SB) and Bad Bin in a Bad Cluster (BBBC)) and an advanced outlier screening method, called Robust Dynamic Part Averaging Testing (RDPAT), as well as two practical improvements, which significantly enhance existing algorithms. Those methods have been used in production in Freescale® Semiconductor probe factories around the world for several years. Moreover, a study was conducted with production data of 289,080 dice with 26 CQIs to determine and compare the efficiency and effectiveness of all these algorithms in identifying CQIs.

  19. Improving Electronic Sensor Reliability by Robust Outlier Screening

    Directory of Open Access Journals (Sweden)

    Federico Cuesta

    2013-10-01

    Full Text Available Electronic sensors are widely used in different application areas, and in some of them, such as automotive or medical equipment, they must perform with an extremely low defect rate. Increasing reliability is paramount. Outlier detection algorithms are a key component in screening latent defects and decreasing the number of customer quality incidents (CQIs. This paper focuses on new spatial algorithms (Good Die in a Bad Cluster with Statistical Bins (GDBC SB and Bad Bin in a Bad Cluster (BBBC and an advanced outlier screening method, called Robust Dynamic Part Averaging Testing (RDPAT, as well as two practical improvements, which significantly enhance existing algorithms. Those methods have been used in production in Freescale® Semiconductor probe factories around the world for several years. Moreover, a study was conducted with production data of 289,080 dice with 26 CQIs to determine and compare the efficiency and effectiveness of all these algorithms in identifying CQIs.

  20. A medical risk attitude subscale for DOSPERT

    Directory of Open Access Journals (Sweden)

    Shoshana Butler

    2012-03-01

    Full Text Available Background: The Domain-Specific Risk Taking scale (DOSPERT is a widely used instrument that measures perceived risk and benefit and attitude toward risk for activities in several domains, but does not include medical risks. Objective: To develop a medical risk domain subscale for DOSPERT. Methods: Sixteen candidate risk items were developed through expert discussion. We conducted cognitive telephone interviews, an online survey, and a random-digit dialing (RDD telephone survey to reduce and refine the scale, explore its factor structure, and obtain estimates of reliability. Participants: Eight patients recruited from UIC medical center waiting rooms participated in 45-60 minute cognitive interviews. Thirty Amazon Mechanical Turk workers completed the online survey. One hundred Chicago-area residents completed the RDD telephone survey. Results: On the basis of cognitive interviews, we eliminated five items due to poor variance or participant misunderstanding. The online survey suggested that two additional items were negatively correlated with the scale, and we considered them candidates for removal. Factor analysis of the responses in the RDD telephone survey and non-statistical factors led us to recommend a final set of 6 items to represent the medical risk domain. The final set of items included blood donation, kidney donation, daily medication use for allergies, knee replacement surgery, general anesthesia in dentistry, and clinical trial participation. The interitem reliability (Cronbach's alpha of the final set of 6 items ranged from 0.57-0.59 depending on the response task. Older respondents gave lower overall ratings of expected benefit from the activities. Conclusion: We refined a set of items to measure risk and benefit perceptions for medical activities. Our next step will be to add these items to the complete DOSPERT scale, confirm the scale's psychometric properties, determine whether medical risks constitute a psychologically

  1. Reliable epileptic seizure detection using an improved wavelet neural network

    Directory of Open Access Journals (Sweden)

    Zarita Zainuddin

    2013-05-01

    Full Text Available BackgroundElectroencephalogram (EEG signal analysis is indispensable in epilepsy diagnosis as it offers valuable insights for locating the abnormal distortions in the brain wave. However, visual interpretation of the massive amounts of EEG signals is time-consuming, and there is often inconsistent judgment between experts. AimsThis study proposes a novel and reliable seizure detection system, where the statistical features extracted from the discrete wavelet transform are used in conjunction with an improved wavelet neural network (WNN to identify the occurrence of seizures. Method Experimental simulations were carried out on a well-known publicly available dataset, which was kindly provided by the Epilepsy Center, University of Bonn, Germany. The normal and epileptic EEG signals were first pre-processed using the discrete wavelet transform. Subsequently, a set of statistical features was extracted to train a WNNs-based classifier. ResultsThe study has two key findings. First, simulation results showed that the proposed improved WNNs-based classifier gave excellent predictive ability, where an overall classification accuracy of 98.87% was obtained. Second, by using the 10th and 90th percentiles of the absolute values of the wavelet coefficients, a better set of EEG features can be identified from the data, as the outliers are removed before any further downstream analysis.ConclusionThe obtained high prediction accuracy demonstrated the feasibility of the proposed seizure detection scheme. It suggested the prospective implementation of the proposed method in developing a real time automated epileptic diagnostic system with fast and accurate response that could assist neurologists in the decision making process.

  2. Results of subscale MTF compression experiments

    Science.gov (United States)

    Howard, Stephen; Mossman, A.; Donaldson, M.; Fusion Team, General

    2016-10-01

    In magnetized target fusion (MTF) a magnetized plasma torus is compressed in a time shorter than its own energy confinement time, thereby heating to fusion conditions. Understanding plasma behavior and scaling laws is needed to advance toward a reactor-scale demonstration. General Fusion is conducting a sequence of subscale experiments of compact toroid (CT) plasmas being compressed by chemically driven implosion of an aluminum liner, providing data on several key questions. CT plasmas are formed by a coaxial Marshall gun, with magnetic fields supported by internal plasma currents and eddy currents in the wall. Configurations that have been compressed so far include decaying and sustained spheromaks and an ST that is formed into a pre-existing toroidal field. Diagnostics measure B, ne, visible and x-ray emission, Ti and Te. Before compression the CT has an energy of 10kJ magnetic, 1 kJ thermal, with Te of 100 - 200 eV, ne 5x1020 m-3. Plasma was stable during a compression factor R0/R >3 on best shots. A reactor scale demonstration would require 10x higher initial B and ne but similar Te. Liner improvements have minimized ripple, tearing and ejection of micro-debris. Plasma facing surfaces have included plasma-sprayed tungsten, bare Cu and Al, and gettering with Ti and Li.

  3. Improving Reliability and Durability of Efficient and Clean Energy Systems

    Energy Technology Data Exchange (ETDEWEB)

    Singh, Prabhakar [Univ. of Connecticut, Storrs, CT (United States)

    2010-08-01

    Overall objective of the research program was to develop an in-depth understanding of the degradation processes in advanced electrochemical energy conversion systems. It was also the objective of the research program to transfer the technology to participating industries for implementation in manufacturing of cost effective and reliable integrated systems.

  4. Aviation Fuel System Reliability and Fail-Safety Analysis. Promising Alternative Ways for Improving the Fuel System Reliability

    Directory of Open Access Journals (Sweden)

    I. S. Shumilov

    2017-01-01

    Full Text Available The paper deals with design requirements for an aviation fuel system (AFS, AFS basic design requirements, reliability, and design precautions to avoid AFS failure. Compares the reliability and fail-safety of AFS and aircraft hydraulic system (AHS, considers the promising alternative ways to raise reliability of fuel systems, as well as elaborates recommendations to improve reliability of the pipeline system components and pipeline systems, in general, based on the selection of design solutions.It is extremely advisable to design the AFS and AHS in accordance with Aviation Regulations АП25 and Accident Prevention Guidelines, ICAO (International Civil Aviation Association, which will reduce risk of emergency situations, and in some cases even avoid heavy disasters.ATS and AHS designs should be based on the uniform principles to ensure the highest reliability and safety. However, currently, this principle is not enough kept, and AFS looses in reliability and fail-safety as compared with AHS. When there are the examined failures (single and their combinations the guidelines to ensure the AFS efficiency should be the same as those of norm-adopted in the Regulations АП25 for AHS. This will significantly increase reliability and fail-safety of the fuel systems and aircraft flights, in general, despite a slight increase in AFS mass.The proposed improvements through the use of components redundancy of the fuel system will greatly raise reliability of the fuel system of a passenger aircraft, which will, without serious consequences for the flight, withstand up to 2 failures, its reliability and fail-safety design will be similar to those of the AHS, however, above improvement measures will lead to a slightly increasing total mass of the fuel system.It is advisable to set a second pump on the engine in parallel with the first one. It will run in case the first one fails for some reasons. The second pump, like the first pump, can be driven from the

  5. Improving intrinsic corrosion reliability of printed circuit board assembly

    DEFF Research Database (Denmark)

    Ambat, Rajan; Conseil, Helene

    2016-01-01

    Corrosion reliability is a serious issue today for electronic devices, components, and bare printed circuit boards (PCBs) due to factors such as miniaturization, globalized manufacturing practices, and global usage. Electronic components and devices are exposed to a wide variety of climatic...... conditions, therefore the protection of electronic devices is becoming a critical factor in system design. Humidity and local condensation inside electronic enclosures can significantly alter the performance of electronic devices. The presence of moisture in a PCB alters its quality, functionality, thermal...

  6. Reliability Centered Maintenance in Schedule Improvement of Automotive Assembly Industry

    OpenAIRE

    Rizauddin Ramli; Mohammad Nizam Arffin

    2012-01-01

    Problem statement: Today, in many automotive manufacturing companies, maintenance management is an important factor to maintain the plant operation and production equipments. Approach: In this study, we present an implementation of Reliability Centered Maintenance (RCM) practice in one of the automotive manufacturing company in Malaysia. The RCM practice was used to assist the company in focusing their maintenance activities based on the criticalities of the equipments by applying the Failure...

  7. Oxidation subscale of gamma-titanium aluminide

    NARCIS (Netherlands)

    Beye, R.; Verwerft, Marc; de Hosson, J.T.M.; Gronsky, R.

    1996-01-01

    The subscale formed during high temperature rapid oxidation of gamma-titanium aluminum is revealed by transmission electron microscopy and microanalysis to consist of two phases: one hexagonal with unit cell dimensions a = 0.58 nm, c = 0.47 nm (+/- 0.005 nm), and a composition close to Ti6Al3O4; the

  8. Ethical Perspectives: Leadership Subscales Applied to Education.

    Science.gov (United States)

    Gable, Sherry K.; Kavich, Larry L.

    Ethical perspectives are needed to gain insight into the history of leader behavior, especially as related to the current emphasis on contingency and Path-Goal Theories. An instrument to help select professionals who reflect ethical traits is the Leadership Behavior Description Questionnaire with 12 leadership subscales (LBDQ, Form XII). Selected…

  9. Improving the reliability of fishery predictions under climate change

    DEFF Research Database (Denmark)

    Brander, Keith

    2015-01-01

    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...... will decline. These levels of confidence seem unwarranted, since many processes are either absent from or poorly represented in the models used, data are sparse and, unlike terrestrial crop projections, there are no controlled experiments.This review discusses methodological issues that affect our...

  10. Improving Reliability and Operational Availability of Military Systems

    National Research Council Canada - National Science Library

    Koehn, Phillip

    2004-01-01

    ...: overhaul and prognostics asset management strategies. It is shown that the prognostics approach leads to improved operational availability by anticipating failure and reducing administrative and logistics delays...

  11. Childhood depression subscales using repeated sessions on Children's Depression Rating Scale - revised (CDRS-R) scores.

    Science.gov (United States)

    Isa, Ameena; Bernstein, Ira; Trivedi, Madhukar; Mayes, Taryn; Kennard, Betsy; Emslie, Graham

    2014-08-01

    Although acute treatments have been shown to be effective in treating early-onset depression, only one-third or thereabouts reach a remission within 3 months. Unfortunately, delayed time to remission in early-onset depression leads to poorer therapeutic outcomes. Clearly, there is a need to identify, diagnose, and provide effective treatment of a depressed patient quickly. A sophisticated understanding of depression subscales and their change over time with treatment could enhance pathways to individualized treatment approaches for childhood depression. Previous studies have found that the clinician-measured instrument, Children's Depression Rating Scale-Revised (CDRS-R) measures multiple subscales (or components) of depression. The aim of this study was to see how these subscales may change over the course of a 12-week study. This knowledge will help determine if dimensions/subscales of childhood depression (paralleling the adult literature) using the subscales derived from factor analysis procedure is useful. We examined two clinical trials in which youth (n=234) with major depressive disorder (MDD) were treated openly with fluoxetine for eight sessions spread over 12 weeks. The CDRS-R was completed based on clinician interviews with parent and child at each session. Classical test theory and component analysis with associated parallel analysis (oblique rotation) were conducted on each week's scores. Although more factors were needed for the baseline and first two therapy sessions, a two-factor solution sufficed thereafter. Depressed facial affect, listless speech, and hypoactivity best defined Factor I, whereas sleep problems, appetite disturbance, physical symptoms, irritability, guilt, and weeping best defined Factor II. All other symptoms cross-loaded almost equally on the two factors. The scale's reliability (internal consistency) improved from baseline to exit sessions (α=0.65-0.91). As a result, the clinicians' assessments of the various symptoms became

  12. METHODS TO IMPROVE THE RELIABILITY OF CREDIT INSTITUTIONS

    Directory of Open Access Journals (Sweden)

    Yu. V. Mishin

    2014-01-01

    Full Text Available This article discusses issues of competitiveness of commercial banks at the expense of future growth profitability and liquidity of credit institutions. To solve this problem is proposed multistage economic and mathematical model. It provides, first, determining the possible volumes of recruitment and placement of funds subject to the minimum level of liquidity , interest rate risk , as well as compliance with prudential regulations of capital adequacy and liquidity , and secondly, based on the enumeration of variable accounting policies and obtain comprehensive reliability assessment forms the best option plan banking. The paper shows the practical implementation of the proposed approach on the example of one of the largest Russian banks – JSC «Bank VTB».

  13. TESTING METHODS FOR MECHANICALLY IMPROVED SOILS: RELIABILITY AND VALIDITY

    Directory of Open Access Journals (Sweden)

    Ana Petkovšek

    2017-10-01

    Full Text Available A possibility of in-situ mechanical improvement for reducing the liquefaction potential of silty sands was investigated by using three different techniques: Vibratory Roller Compaction, Rapid Impact Compaction (RIC and Soil Mixing. Material properties at all test sites were investigated before and after improvement with the laboratory and the in situ tests (CPT, SDMT, DPSH B, static and dynamic load plate test, geohydraulic tests. Correlation between the results obtained by different test methods gave inconclusive answers.

  14. Wind Turbine Blade Design for Subscale Testing

    Science.gov (United States)

    Hassanzadeh, Arash; Naughton, Jonathan W.; Kelley, Christopher L.; Maniaci, David C.

    2016-09-01

    Two different inverse design approaches are proposed for developing wind turbine blades for sub-scale wake testing. In the first approach, dimensionless circulation is matched for full scale and sub-scale wind turbine blades for equal shed vorticity in the wake. In the second approach, the normalized normal and tangential force distributions are matched for large scale and small scale wind turbine blades, as these forces determine the wake dynamics and stability. The two approaches are applied for the same target full scale turbine blade, and the shape of the blades are compared. The results show that the two approaches have been successfully implemented, and the designed blades are able to produce the target circulation and target normal and tangential force distributions.

  15. Improving the Reliability of Tinnitus Screening in Laboratory Animals.

    Science.gov (United States)

    Jones, Aikeen; May, Bradford J

    2017-02-01

    Behavioral screening remains a contentious issue for animal studies of tinnitus. Most paradigms base a positive tinnitus test on an animal's natural tendency to respond to the "sound" of tinnitus as if it were an actual sound. As a result, animals with tinnitus are expected to display sound-conditioned behaviors when no sound is present or to miss gaps in background sounds because tinnitus "fills in the gap." Reliable confirmation of the behavioral indications of tinnitus can be problematic because the reinforcement contingencies of conventional discrimination tasks break down an animal's tendency to group tinnitus with sound. When responses in silence are rewarded, animals respond in silence regardless of their tinnitus status. When responses in silence are punished, animals stop responding. This study introduces stimulus classification as an alternative approach to tinnitus screening. Classification procedures train animals to respond to the common perceptual features that define a group of sounds (e.g., high pitch or narrow bandwidth). Our procedure trains animals to drink when they hear tinnitus and to suppress drinking when they hear other sounds. Animals with tinnitus are revealed by their tendency to drink in the presence of unreinforced probe sounds that share the perceptual features of the tinnitus classification. The advantages of this approach are illustrated by taking laboratory rats through a testing sequence that includes classification training, the experimental induction of tinnitus, and postinduction screening. Behavioral indications of tinnitus are interpreted and then verified by simulating a known tinnitus percept with objective sounds.

  16. Subscale Test Program for the Orion Conical Ribbon Drogue Parachute

    Science.gov (United States)

    Sengupta, Anita; Stuart, Phil; Machin, Ricardo; Bourland, Gary; Schwing, Allen; Longmire, Ellen; Henning, Elsa; Sinclair, Rob

    2011-01-01

    A subscale wind tunnel test program for Orion's conical ribbon drogue parachute is under development. The desired goals of the program are to quantify aerodynamic performance of the parachute in the wake of the entry vehicle, including understanding of the coupling of the parachute and command module dynamics, and an improved understanding of the load distribution within the textile elements of the parachute. The test program is ten percent of full scale conducted in a 3x2.1 m (10x7 ft) closed loop subsonic wind tunnel. The subscale test program is uniquely suited to probing the aerodynamic and structural environment in both a quantitative and qualitative manner. Non-intrusive diagnostics, including Particle Image Velocimetry for wake velocity surveys, high speed pressure transducers for canopy pressure distribution, and a high speed photogrammetric reconstruction, will be used to quantify the parachute's performance.

  17. Advanced surface protection for improved reliability PCB systems (ASPIS)

    NARCIS (Netherlands)

    Ballantyne, A.; Forrest, G.; Goosey, M.; Griguceviciene, A.; Juodkazyte, J.; Kellner, R.; Kosenko, A.; Ramanauskas, R.; Ryder, K.; Selskis, A.; Tarozaite, R.; Veninga, E.

    2012-01-01

    Purpose - The purpose of this paper is to detail progress on the European Commission supported FP7 ASPIS project that is undertaking a multi-faceted approach to develop novel and improved nickel-gold (ENIG) solderable finish chemistries and processes in order to overcome issues such as "black pad"

  18. Improving Punctuality and Transfer Reliability by Railway Timetable Optimization

    NARCIS (Netherlands)

    Goverde, R.M.P.

    1999-01-01

    The Dutch railway network is operated close to capacity with the current safety system. This leaves little space for control by process operators by which a delayed train can cause severe delay propagation. The NS currently invest a large amount in punctuality improvement of the railway operations.

  19. Improving Sample Estimate Reliability and Validity with Linked Ego Networks

    CERN Document Server

    Lu, Xin

    2012-01-01

    Respondent-driven sampling (RDS) is currently widely used in public health, especially for the study of hard-to-access populations such as injecting drug users and men who have sex with men. The method works like a snowball sample but can, given that some assumptions are met, generate unbiased population estimates. However, recent studies have shown that traditional RDS estimators are likely to generate large variance and estimate error. To improve the performance of traditional estimators, we propose a method to generate estimates with ego network data collected by RDS. By simulating RDS processes on an empirical human social network with known population characteristics, we have shown that the precision of estimates on the composition of network link types is greatly improved with ego network data. The proposed estimator for population characteristics shows superior advantage over traditional RDS estimators, and most importantly, the new method exhibits strong robustness to the recruitment preference of res...

  20. Thin-Film Reliability Trends Toward Improved Stability: Preprint

    Energy Technology Data Exchange (ETDEWEB)

    Jordan, D. C.; Kurtz, S. R.

    2011-07-01

    Long-term, stable performance of photovoltaic (PV) modules will be increasingly important to their successful penetration of the power grid. This paper summarizes more than 150 thin-film and more than 1700 silicon PV degradation rates (Rd) quoted in publications for locations worldwide. Partitioning the literature results by technology and date of installation statistical analysis shows an improvement in degradation rate especially for thin-film technologies in the last decade. A CIGS array deployed at NREL for more than 5 years that appears to be stable supports the literature trends. Indoor and outdoor data indicate undetectable change in performance (0.2+/-0.2 %/yr). One module shows signs of slight degradation from what appears to be an initial manufacturing defect, however it has not affected the overall system performance.

  1. STUDIES ON IGBT MODULE TO IMPROVE THE RELIABILITY OF POWER ELECTRONIC SYSTEMS

    DEFF Research Database (Denmark)

    Choi, Uimin

    that kills IGBT modules. Therefore, in order to improve the reliability of power electronic systems, reliability research on reliability-critical components regarding the major critical stressors are needed. In this PhD project, various researches on reliability of the IGBT module are performed from...... are presented. Then, in Chapter 3, the effect of junction temperature swing duration t△Tj on the lifetime of the transfer molded Intelligent Power IGBT Module is investigated and modeled based on the power cycling test results. In addition, the physics-of-failure analysis results of the tested modules...

  2. Reliability Evaluation and Improvement Approach of Chemical Production Man - Machine - Environment System

    Science.gov (United States)

    Miao, Yongchun; Kang, Rongxue; Chen, Xuefeng

    2017-12-01

    In recent years, with the gradual extension of reliability research, the study of production system reliability has become the hot topic in various industries. Man-machine-environment system is a complex system composed of human factors, machinery equipment and environment. The reliability of individual factor must be analyzed in order to gradually transit to the research of three-factor reliability. Meanwhile, the dynamic relationship among man-machine-environment should be considered to establish an effective blurry evaluation mechanism to truly and effectively analyze the reliability of such systems. In this paper, based on the system engineering, fuzzy theory, reliability theory, human error, environmental impact and machinery equipment failure theory, the reliabilities of human factor, machinery equipment and environment of some chemical production system were studied by the method of fuzzy evaluation. At last, the reliability of man-machine-environment system was calculated to obtain the weighted result, which indicated that the reliability value of this chemical production system was 86.29. Through the given evaluation domain it can be seen that the reliability of man-machine-environment integrated system is in a good status, and the effective measures for further improvement were proposed according to the fuzzy calculation results.

  3. Reliability Improvement of Power Converters by Means of Condition Monitoring of IGBT Modules

    DEFF Research Database (Denmark)

    Choi, Ui Min; Blaabjerg, Frede; Jørgensen, S.

    2017-01-01

    Power electronic systems have gradually gained an important status in a wide range of industrial applications such as renewable generation, motor drives, automotive, and railway transportation. Accordingly, recent research makes an effort to improve the reliability of power electronic systems...... to comply with more stringent constraints on safety, cost, and availability. The power devices are one of the most reliability-critical components in power electronic systems. Therefore, its condition monitoring plays an important role to improve the reliability of power electronic systems. This paper...

  4. Improved Reliability-Based Optimization with Support Vector Machines and Its Application in Aircraft Wing Design

    Directory of Open Access Journals (Sweden)

    Yu Wang

    2015-01-01

    Full Text Available A new reliability-based design optimization (RBDO method based on support vector machines (SVM and the Most Probable Point (MPP is proposed in this work. SVM is used to create a surrogate model of the limit-state function at the MPP with the gradient information in the reliability analysis. This guarantees that the surrogate model not only passes through the MPP but also is tangent to the limit-state function at the MPP. Then, importance sampling (IS is used to calculate the probability of failure based on the surrogate model. This treatment significantly improves the accuracy of reliability analysis. For RBDO, the Sequential Optimization and Reliability Assessment (SORA is employed as well, which decouples deterministic optimization from the reliability analysis. The improved SVM-based reliability analysis is used to amend the error from linear approximation for limit-state function in SORA. A mathematical example and a simplified aircraft wing design demonstrate that the improved SVM-based reliability analysis is more accurate than FORM and needs less training points than the Monte Carlo simulation and that the proposed optimization strategy is efficient.

  5. Reliability improvements on Thales RM2 rotary Stirling coolers: analysis and methodology

    Science.gov (United States)

    Cauquil, J. M.; Seguineau, C.; Martin, J.-Y.; Benschop, T.

    2016-05-01

    The cooled IR detectors are used in a wide range of applications. Most of the time, the cryocoolers are one of the components dimensioning the lifetime of the system. The cooler reliability is thus one of its most important parameters. This parameter has to increase to answer market needs. To do this, the data for identifying the weakest element determining cooler reliability has to be collected. Yet, data collection based on field are hardly usable due to lack of informations. A method for identifying the improvement in reliability has then to be set up which can be used even without field return. This paper will describe the method followed by Thales Cryogénie SAS to reach such a result. First, a database was built from extensive expertizes of RM2 failures occurring in accelerate ageing. Failure modes have then been identified and corrective actions achieved. Besides this, a hierarchical organization of the functions of the cooler has been done with regard to the potential increase of its efficiency. Specific changes have been introduced on the functions most likely to impact efficiency. The link between efficiency and reliability will be described in this paper. The work on the two axes - weak spots for cooler reliability and efficiency - permitted us to increase in a drastic way the MTTF of the RM2 cooler. Huge improvements in RM2 reliability are actually proven by both field return and reliability monitoring. These figures will be discussed in the paper.

  6. Equipment reliability improvement process; implementation in Almaraz NPP and Trillo NPP

    Energy Technology Data Exchange (ETDEWEB)

    Risquez Bailon, Aranzazu; Gutierrez Fernandez, Eduardo [Nuclear Engineering Division, Iberdrola Ingenieria y Construccion, S.A.U., Avda. de Manoteras 20 Edif.C, 28050 Madrid (Spain)

    2010-07-01

    The Equipment Reliability Improvement Process (INPO AP-913) is a non-regulatory process developed by the US Nuclear Industry for improving Plants Availability. This Process integrates and coordinates a broad range of equipment reliability activities into one process, performed by the Plant in a non-centralized way. The integration and coordination of these activities will allow plant personnel to evaluate the trends of important station equipment, develop and implement long-term equipment health plans, monitor equipment performance and condition, and make adjustments to preventive maintenance tasks and frequencies based on equipment operating experience, if necessary, arbitrating operational and design improvements, to reach a Failure-free Operation. This paper describes the methodology of Equipment Reliability Improvement Process, being focused on main aspects of the implementation process, relating to the scope and establishment of an Equipment Reliability Monitoring Plan, which should include and complement the existing mechanisms and organizations in the Plant to monitor the condition and performance of the equipments, with the common aim of achieving an operation free of failures. The paper will describe the tools that Iberdrola Ingenieria has developed to support the implementation and monitoring of the Equipment Reliability Improvement Process, as well as the results and lessons learned from its implementation in Almaraz NPP and Trillo NPP. (authors)

  7. Maintenance and improvement of interobserver reliability of osteopathic palpatory tests over a 4-month period.

    Science.gov (United States)

    Degenhardt, Brian F; Johnson, Jane C; Snider, Karen T; Snider, Eric J

    2010-10-01

    Few studies have shown that diagnostic palpation is reliable. No studies have shown that the reliability of diagnostic palpatory skills can be maintained and improved over time. To investigate whether the reliability of selected palpatory tests used to identify lumbar somatic dysfunction was maintained during a 4-month period as part of a clinical observational study. Participants with low back pain and participants without low back pain, recruited from a rural Midwestern community, were examined during 6 separate sessions over a 4-month period. During each data collection session, two blinded examiners, who had previously completed comprehensive consensus training, evaluated the lumbar region with four tests: static segmental positional asymmetry of the transverse processes in the horizontal plane, tissue texture abnormalities, resistance to anterior springing on the spinous processes, and tenderness induced by pressure on the spinous processes. Detailed protocols for each test were defined during a previous comprehensive consensus training period and were not revised during the current study. To verify that established interobserver reliability was maintained throughout the clinical study, quality control sampling was performed on all data. When findings were inconsistent between the two examiners, focused consensus training was performed as a means of recalibration to understand why assessments were inconsistent. Interobserver reliability for determining the presence or absence of somatic dysfunction was assessed using kappa coefficients. The study enrolled 64 participants, and 14 to 33 participants were examined per session. All four tests had acceptable interobserver reliability by the final data collection session. The test for static segmental positional asymmetry of the transverse processes in the horizontal plane had moderate to substantial reliability in all 6 sessions. The test for tissue texture abnormalities had moderate reliability in 5 of the 6

  8. Development and validation of the functional assessment of cancer therapy-antiangiogenesis subscale.

    Science.gov (United States)

    Kaiser, Karen; Beaumont, Jennifer L; Webster, Kimberly; Yount, Susan E; Wagner, Lynne I; Kuzel, Timothy M; Cella, David

    2015-05-01

    The Functional Assessment of Cancer Therapy (FACT)-Antiangiogenesis (AntiA) Subscale was developed and validated to enhance treatment decision-making and side effect management for patients receiving anti-angiogenesis therapies. Side effects related to anti-angiogenesis therapies were identified from the literature, clinician input, and patient input. Fifty-nine possible patient expressions of side effects were generated. Patient and clinician ratings of the importance of these expressions led us to develop a 24-item questionnaire with clinical and research potential. To assess the scale's reliability and validity, 167 patients completed the AntiA Subscale, the Functional Assessment of Cancer Therapy-general (FACT-G), the FACT-Kidney Symptom Index (FKSI), the FACIT-Fatigue Subscale, the Global Rating of Change Scale (GRC), and the PROMIS Global Health Scale. Patient responses to the AntiA were analyzed for internal consistency, test-retest reliability, convergent and discriminant validity, and responsiveness to change in clinical status. All tested scales were found to have good internal consistency reliability (Cronbach's alpha 0.70-0.92). Test-retest reliability was also good (0.72-0.88) for total and subscale scores and lower for individual items. The total score, subscale scores, and all single items (except nosebleeds) significantly differentiated between groups defined by level of side effect bother. Evaluation of responsiveness to change in this study was not conclusive, suggesting an area for further research. The AntiA is a reliable and valid measure of side effects from anti-angiogenesis therapy. © 2014 The Authors. Cancer Medicine published by John Wiley & Sons Ltd.

  9. Development and validation of the functional assessment of cancer therapy–antiangiogenesis subscale

    Science.gov (United States)

    Kaiser, Karen; Beaumont, Jennifer L; Webster, Kimberly; Yount, Susan E; Wagner, Lynne I; Kuzel, Timothy M; Cella, David

    2015-01-01

    The Functional Assessment of Cancer Therapy (FACT)–Antiangiogenesis (AntiA) Subscale was developed and validated to enhance treatment decision-making and side effect management for patients receiving anti-angiogenesis therapies. Side effects related to anti-angiogenesis therapies were identified from the literature, clinician input, and patient input. Fifty-nine possible patient expressions of side effects were generated. Patient and clinician ratings of the importance of these expressions led us to develop a 24-item questionnaire with clinical and research potential. To assess the scale's reliability and validity, 167 patients completed the AntiA Subscale, the Functional Assessment of Cancer Therapy-general (FACT-G), the FACT-Kidney Symptom Index (FKSI), the FACIT-Fatigue Subscale, the Global Rating of Change Scale (GRC), and the PROMIS Global Health Scale. Patient responses to the AntiA were analyzed for internal consistency, test–retest reliability, convergent and discriminant validity, and responsiveness to change in clinical status. All tested scales were found to have good internal consistency reliability (Cronbach's alpha 0.70–0.92). Test–retest reliability was also good (0.72–0.88) for total and subscale scores and lower for individual items. The total score, subscale scores, and all single items (except nosebleeds) significantly differentiated between groups defined by level of side effect bother. Evaluation of responsiveness to change in this study was not conclusive, suggesting an area for further research. The AntiA is a reliable and valid measure of side effects from anti-angiogenesis therapy. PMID:25619758

  10. Improving the reliability of fuel Enusa; Mejora de la fiabilidad del combustible en Enusa

    Energy Technology Data Exchange (ETDEWEB)

    Choithramani, S.; Quecedo, M.

    2015-07-01

    ENUSA is committed to providing our customers with fuel designs that meet their needs for operational efficiency, power, energy, performance and reliability. ENUSAs current fuel designs, covering BWR and PWR technologies, incorporate highest performance with proven reliability features developed along nuclear power operation history. As of January 2015, ENUSA has manufactured more than 20.000 fuel assemblies (around half BWR and half PWR), with operating conditions reflecting varying reactor power densities, cycle lengths, operating strategies and water chemistry environments. This experience brings the knowledge to model our fuel behavior and acts as the principal instrument to identify and characterize the failure mechanisms of our fuel. Based on the information obtained from all this years of operation, ENUSA has progressively developed and implemented numerous mitigating actions identified upon the knowledge on failure mechanisms, which are the bases for the fuel reliability improvement program. Contemporaneously to this implementation, a positive trend on ENUSA fuel reliability has been observed. (Author)

  11. The patellofemoral pain and osteoarthritis subscale of the KOOS (KOOS-PF)

    DEFF Research Database (Denmark)

    Crossley, Kay M; Macri, Erin M; Cowan, Sallie M

    2017-01-01

    for patellofemoral pain have methodological limitations. This study aimed to develop a new subscale of the Knee injury and Osteoarthritis Outcome Score for patellofemoral pain and osteoarthritis (KOOS-PF), and evaluate its measurement properties. METHODS: Items were generated using input from 50 patients...... and interpretability of the final version of KOOS-PF and other KOOS subscales. RESULTS: From an initial 80 generated items, the final subscale included 11 items. KOOS-PF items loaded predominantly on one factor, pain during activities that load the patellofemoral joint. KOOS-PF had good internal consistency (Cronbach......'s α 0.86) and adequate test-retest reliability (intraclass correlation coefficient 0.86). Hypothesis testing supported convergent, divergent and known-groups validity. Responsiveness was confirmed, with KOOS-PF demonstrating a moderate correlation with Global Rating of Change scores (r 0.52) and large...

  12. 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

  13. Complex method to calculate objective assessments of information systems protection to improve expert assessments reliability

    Science.gov (United States)

    Abdenov, A. Zh; Trushin, V. A.; Abdenova, G. A.

    2018-01-01

    The paper considers the questions of filling the relevant SIEM nodes based on calculations of objective assessments in order to improve the reliability of subjective expert assessments. The proposed methodology is necessary for the most accurate security risk assessment of information systems. This technique is also intended for the purpose of establishing real-time operational information protection in the enterprise information systems. Risk calculations are based on objective estimates of the adverse events implementation probabilities, predictions of the damage magnitude from information security violations. Calculations of objective assessments are necessary to increase the reliability of the proposed expert assessments.

  14. IMPROVING SOLUTIONS OF EQUIPMENT’S RELIABILITY FOR DETECTION OF GROUNDING LINES

    Directory of Open Access Journals (Sweden)

    PĂCUREANU I.

    2015-12-01

    Full Text Available The paper has three parts, in the first one, is presented the theoretical concepts that refer on the grounding lines fault, the treating mode, and implemented solutions for their detection in electric stations. In the second part is presented the result of the operational reliability analyse in period of 2011 – 2015, as in the final part of the paper are given the conclusions and identified solutions regarding the improving of operational reliability of the protection equipment of detection of grounding lines.

  15. Eastern Cape piloting of CSIR research to improve water services reliability

    CSIR Research Space (South Africa)

    Wall, K

    2010-09-01

    Full Text Available piloting of CSIR research to improve water services reliability K WALL1, J BHAGWAN2 AND O IVE3 1CSIR Built Environment, PO Box 395, Pretoria, 0001, South Africa 2Water Research Commission 3Amanz’abantu Services Email: kwall@csir.co.za – www... and hygiene at the schools it has reached to date. The emphasis is on the quality and reliability of the service delivered, and the viability of the franchisor and franchisees. The state of the sanitation facilities at the pilot schools has so much...

  16. Embedded Sensors and Controls to Improve Component Performance and Reliability Conceptual Design Report

    Energy Technology Data Exchange (ETDEWEB)

    Kisner, R.; Melin, A.; Burress, T.; Fugate, D.; Holcomb, D.; Wilgen, J.; Miller, J.; Wilson, D.; Silva, P.; Whitlow, L.; Peretz, F.

    2012-09-15

    The objective of this project is to demonstrate improved reliability and increased performance made possible by deeply embedding instrumentation and controls (I&C) in nuclear power plant (NPP) components and systems. The project is employing a highly instrumented canned rotor, magnetic bearing, fluoride salt pump as its I&C technology demonstration platform. I&C is intimately part of the basic millisecond-by-millisecond functioning of the system; treating I&C as an integral part of the system design is innovative and will allow significant improvement in capabilities and performance. As systems become more complex and greater performance is required, traditional I&C design techniques become inadequate and more advanced I&C needs to be applied. New I&C techniques enable optimal and reliable performance and tolerance of noise and uncertainties in the system rather than merely monitoring quasistable performance. Traditionally, I&C has been incorporated in NPP components after the design is nearly complete; adequate performance was obtained through over-design. By incorporating I&C at the beginning of the design phase, the control system can provide superior performance and reliability and enable designs that are otherwise impossible. This report describes the progress and status of the project and provides a conceptual design overview for the platform to demonstrate the performance and reliability improvements enabled by advanced embedded I&C.

  17. reliability reliability

    African Journals Online (AJOL)

    eobe

    In this work, a FORTRAN-based computer computer. Eurocode 2 (EC 2)[1] ... addresses addresses: 1 idrcivil1@yahoo.com, 2 adomaarf1@gmail.com computer computer program was developed to aid the design of reinforced co program was ..... Haldar, A. and Mahadevan, S. Reliability Assessment using Stochastic Finite ...

  18. Cost effectiveness and reliability improvement capabilities of CHECWORKS and SWIPS based inspection and maintenance plans

    Energy Technology Data Exchange (ETDEWEB)

    Singh, S. [United Dynamics, Malvern, PA (United States); Borodotsky, A. [Rochester Gas and Electric Corp., NY (United States)

    1996-11-01

    CHECWORKS and SWIPS are computer programs that undertaken degradation analysis and generate prioritized lists for scheduling inspections. A simplified analysis presented in this paper demonstrates that application of such computer aided degeneration analysis and prioritized list based I and M plans can achieve full system reliability along with high cost effectiveness. For purposes of developing insight and a basic understanding, relative cost-effectiveness and system reliability improvement analysis is conducted on a small service water system for five types of inspection and maintenance plans. The following plans are considered: a full inspection plan, a random sampling plan, an experienced based sampling plan, a computer aided degeneration analysis based plan, and a superman based plan. The results obtained show that a computer aided inspection plan is the most effective of the feasible plans. For a realistic system, the plan can pay for the analysis cost and generate additional cost savings while maintaining full system reliability.

  19. Hosts improve the reliability of chick recognition by delaying the hatching of brood parasitic eggs.

    Science.gov (United States)

    Shizuka, Daizaburo; Lyon, Bruce E

    2011-03-22

    The reliability of information that animals use to make decisions has fitness consequences. Accordingly, selection should favor the evolution of strategies that enhance the reliability of information used in learning and decision making. For example, hosts of avian brood parasites should be selected to increase the reliability of the information they use to learn to recognize their own eggs and chicks. The American coot (Fulica americana), a conspecific brood parasite, uses cues learned from the first-hatched chicks of each brood to recognize and reject parasitic chicks. However, if parasitic eggs are among the first to hatch, recognition cues are confounded and parents then fail to distinguish parasitic chicks from their own chicks. Therefore, hosts could ensure correct chick recognition by delaying parasitic eggs from hatching until after the first host eggs. Here we demonstrate that discriminatory incubation, whereby coots specifically delay the hatching of parasitic eggs, improves the reliability of parasitic chick recognition. In effect, coots gain fitness benefits by enhancing the reliability of information they later use for learning. Our study shows that a positive interaction between two host adaptations in coots--egg recognition and chick recognition--increases the overall effectiveness of host defense. Copyright © 2011 Elsevier Ltd. All rights reserved.

  20. Group assessments of resident physicians improve reliability and decrease halo error.

    Science.gov (United States)

    Thomas, Matthew R; Beckman, Thomas J; Mauck, Karen F; Cha, Stephen S; Thomas, Kris G

    2011-07-01

    Individual faculty assessments of resident competency are complicated by inconsistent application of standards, lack of reliability, and the "halo" effect. We determined whether the addition of faculty group assessments of residents in an ambulatory clinic, compared with individual faculty-of-resident assessments alone, have better reliability and reduced halo effects. This prospective, longitudinal study was performed in the outpatient continuity clinics of a large internal medicine residency program. Faculty-on-resident and group faculty-on-resident assessment scores were used for comparison. Overall mean scores were significantly higher for group than individual assessments (3.92 ± 0.51 vs. 3.83 ± 0.38, p = 0.0001). Overall inter-rater reliability increased when combining group and individual assessments compared to individual assessments alone (intraclass correlation coefficient, 95% CI = 0.828, 0.785-0.866 vs. 0.749, 0.686-0.804). Inter-item correlations were less for group (0.49) than individual (0.68) assessments. This study demonstrates improved inter-rater reliability and reduced range restriction (halo effect) of resident assessment across multiple performance domains by adding the group assessment method to traditional individual faculty-on-resident assessment. This feasible model could help graduate medical education programs achieve more reliable and discriminating resident assessments.

  1. Improvement of reliability of opencast mining techniques in difficult geological, mining and climatic conditions

    Energy Technology Data Exchange (ETDEWEB)

    1986-02-20

    The intensification of opencast coal mining in the USSR has been connected with the introduction of technological systems involving excavator loading of the spoil at opencast mines in the Soviet Far East, Eastern Siberia, the Kuzbass and other areas with difficult natural and climatic conditions. This paper discusses means of improving reliability of opencast mining and gives suggestions. Topics covered include methods of increasing the size of internal dumps while maintaining stability where internal dumps are often on worked out opencast sites. The principle method used to increase stability is that of preparing the base of the dump by providing special preventative excavations. Improvements in the non-transport system of internal dumping have been made although methods using conveyor spoil stackers involve the drainage of the deposit. Improved reliability of opencast mining also involves the efficiency of blasting operations. One method discussed in the paper is the use of multipoint initiation of explosive charges to reduce misfires of borehole charges and a numerical probability assessment is described. The improvement in reliability of means of transport at opencast mines is also described mainly due to technological advances.

  2. Improved radiograph measurement inter-observer reliability by use of statistical shape models

    Energy Technology Data Exchange (ETDEWEB)

    Pegg, E.C., E-mail: elise.pegg@ndorms.ox.ac.uk [University of Oxford, Nuffield Department of Orthopaedics, Rheumatology and Musculoskeletal Sciences, Nuffield Orthopaedic Centre, Windmill Road, Oxford OX3 7LD (United Kingdom); Mellon, S.J., E-mail: stephen.mellon@ndorms.ox.ac.uk [University of Oxford, Nuffield Department of Orthopaedics, Rheumatology and Musculoskeletal Sciences, Nuffield Orthopaedic Centre, Windmill Road, Oxford OX3 7LD (United Kingdom); Salmon, G. [University of Oxford, Nuffield Department of Orthopaedics, Rheumatology and Musculoskeletal Sciences, Nuffield Orthopaedic Centre, Windmill Road, Oxford OX3 7LD (United Kingdom); Alvand, A., E-mail: abtin.alvand@ndorms.ox.ac.uk [University of Oxford, Nuffield Department of Orthopaedics, Rheumatology and Musculoskeletal Sciences, Nuffield Orthopaedic Centre, Windmill Road, Oxford OX3 7LD (United Kingdom); Pandit, H., E-mail: hemant.pandit@ndorms.ox.ac.uk [University of Oxford, Nuffield Department of Orthopaedics, Rheumatology and Musculoskeletal Sciences, Nuffield Orthopaedic Centre, Windmill Road, Oxford OX3 7LD (United Kingdom); Murray, D.W., E-mail: david.murray@ndorms.ox.ac.uk [University of Oxford, Nuffield Department of Orthopaedics, Rheumatology and Musculoskeletal Sciences, Nuffield Orthopaedic Centre, Windmill Road, Oxford OX3 7LD (United Kingdom); Gill, H.S., E-mail: richie.gill@ndorms.ox.ac.uk [University of Oxford, Nuffield Department of Orthopaedics, Rheumatology and Musculoskeletal Sciences, Nuffield Orthopaedic Centre, Windmill Road, Oxford OX3 7LD (United Kingdom)

    2012-10-15

    Pre- and post-operative radiographs of patients undergoing joint arthroplasty are often examined for a variety of purposes including preoperative planning and patient assessment. This work examines the feasibility of using active shape models (ASM) to semi-automate measurements from post-operative radiographs for the specific case of the Oxford™ Unicompartmental Knee. Measurements of the proximal tibia and the position of the tibial tray were made using the ASM model and manually. Data were obtained by four observers and one observer took four sets of measurements to allow assessment of the inter- and intra-observer reliability, respectively. The parameters measured were the tibial tray angle, the tray overhang, the tray size, the sagittal cut position, the resection level and the tibial width. Results demonstrated improved reliability (average of 27% and 11.2% increase for intra- and inter-reliability, respectively) and equivalent accuracy (p > 0.05 for compared data values) for all of the measurements using the ASM model, with the exception of the tray overhang (p = 0.0001). Less time (15 s) was required to take measurements using the ASM model compared with manual measurements, which was significant. These encouraging results indicate that semi-automated measurement techniques could improve the reliability of radiographic measurements.

  3. Improving reliability of clinical care practices for ventilated patients in the context of a patient safety improvement initiative.

    Science.gov (United States)

    Pinto, Anna; Burnett, Susan; Benn, Jonathan; Brett, Stephen; Parand, Anam; Iskander, Sandra; Vincent, Charles

    2011-02-01

    To investigate perceived factors relating to the reliable application of four clinical care practices targeting ventilator-associated pneumonias, in the context of a patient safety improvement initiative called the Safer Patients Initiative (SPI). Qualitative case study. Seventeen semi-structured individual interviews with clinical operational leads, programme coordinators and executive managers who were involved in the implementation of the programme's critical care work stream during its pilot phase. The interviews had a focus on perceived aspects pertaining to the reliable implementation of the four clinical practices, promoted by the Institute for Healthcare Improvement as the 'ventilator care bundle'. Thematic analysis of the verbatim transcripts revealed three overarching themes experienced by the participants during the implementation of the clinical practices included in the SPI ventilator care bundle: the power of measurement, feedback to peers and experts and improvement tools specific to SPI. Consistent measurement of compliance with the four elements of the bundle and outcomes made the staff realize that their engagement in previous improvement work for ventilated patients was inadequate and motivated them to apply the introduced clinical practices more reliably. Feedback to experts and peers of staff compliance with the four clinical practices and outcome improvement was perceived as a very influential aspect of SPI. Small tests of change (Plan-Do-Study-Act cycles), teaching sessions and daily goal sheets were quoted as particularly useful tools throughout the implementation of the four clinical care practices. Future initiatives that aim to improve the adherence of clinical staff with clinical practice guidelines in intensive care units could benefit from integrating in their methodology consistent measurement and feedback practices of both process compliance and outcome data. © 2010 Blackwell Publishing Ltd.

  4. Attitude Control of Quad-rotor by Improving the Reliability of Multi-Sensor System

    Energy Technology Data Exchange (ETDEWEB)

    Yu, Dong Hyeon; Chong, Kil To [Chon-bok National University, Jeonju (Korea, Republic of); Park, Jong Ho [Seonam University, Namwon (Korea, Republic of); Ryu, Ji Hyoung [ETRI, Daejeon (Korea, Republic of)

    2015-05-15

    This paper presents the results of study for improving the reliability of quadrotor attitude control by applying a multi-sensor along with a data fusion algorithm. First, a mathematical model of the quadrotor dynamics was developed. Then, using the quadrotor mathematical model, simulations were performed using the improved reliability multi-sensor data as the inputs. From the simulation results, we designed a Gimbal-equipped quadrotor system. With the quadrotor in a hover state, we performed experiments according to the angle change of the user's specifications . We then calculated the attitude control data from the actual experimental data. Furthermore, with additional simulations, we verified the performance of the designed quadrotor attitude control system with multiple sensors.

  5. Improved Reliability of SiC Pressure Sensors for Long Term High Temperature Applications

    Science.gov (United States)

    Okojie, R. S.; Nguyen, V.; Savrun, E.; Lukco, D.

    2011-01-01

    We report advancement in the reliability of silicon carbide pressure sensors operating at 600 C for extended periods. The large temporal drifts in zero pressure offset voltage at 600 C observed previously were significantly suppressed to allow improved reliable operation. This improvement was the result of further enhancement of the electrical and mechanical integrity of the bondpad/contact metallization, and the introduction of studded bump bonding on the pad. The stud bump contact promoted strong adhesion between the Au bond pad and the Au die-attach. The changes in the zero offset voltage and bridge resistance over time at temperature were explained by the microstructure and phase changes within the contact metallization, that were analyzed with Auger electron spectroscopy (AES) and field emission scanning electron microscopy (FE-SEM).

  6. Longitudinal Construct Validity of Brief Symptom Inventory Subscales in Schizophrenia

    Science.gov (United States)

    Long, Jeffrey D.; Harring, Jeffrey R.; Brekke, John S.; Test, Mary Ann; Greenberg, Jan

    2007-01-01

    Longitudinal validity of Brief Symptom Inventory subscales was examined in a sample (N = 318) with schizophrenia-related illness measured at baseline and every 6 months for 3 years. Nonlinear factor analysis of items was used to test graded response models (GRMs) for subscales in isolation. The models varied in their within-time and between-times…

  7. Assessing motivation for work environment improvements: internal consistency, reliability and factorial structure.

    Science.gov (United States)

    Hedlund, Ann; Ateg, Mattias; Andersson, Ing-Marie; Rosén, Gunnar

    2010-04-01

    Workers' motivation to actively take part in improvements to the work environment is assumed to be important for the efficiency of investments for that purpose. That gives rise to the need for a tool to measure this motivation. A questionnaire to measure motivation for improvements to the work environment has been designed. Internal consistency and test-retest reliability of the domains of the questionnaire have been measured, and the factorial structure has been explored, from the answers of 113 employees. The internal consistency is high (0.94), as well as the correlation for the total score (0.84). Three factors are identified accounting for 61.6% of the total variance. The questionnaire can be a useful tool in improving intervention methods. The expectation is that the tool can be useful, particularly with the aim of improving efficiency of companies' investments for work environment improvements. Copyright 2010 Elsevier Ltd. All rights reserved.

  8. Improving the reliability of verbal communication between primary care physicians and pediatric hospitalists at hospital discharge.

    Science.gov (United States)

    Mussman, Grant M; Vossmeyer, Michael T; Brady, Patrick W; Warrick, Denise M; Simmons, Jeffrey M; White, Christine M

    2015-09-01

    Timely and reliable verbal communication between hospitalists and primary care physicians (PCPs) is critical for prevention of medical adverse events but difficult in practice. Our aim was to increase the proportion of completed verbal handoffs from on-call residents or attendings to PCPs within 24 hours of patient discharge from a hospital medicine service to ≥90% within 18 months. A multidisciplinary team collaborated to redesign the process by which PCPs were contacted following patient discharge. Interventions focused on the key drivers of obtaining stakeholder buy-in, standardization of the communication process, including assigning primary responsibility for discharge communication to a single resident on each team and batching calls during times of maximum resident availability, reliable automated process initiation through leveraging the electronic health record (EHR), and transparency of data. A run chart assessed the impact of interventions over time. The percentage of calls initiated within 24 hours of discharge improved from 52% to 97%, and the percentage of calls completed improved to 93%. Results were sustained for 18 months. Standardization of the communication process through hospital telephone operators, use of the discharge order to ensure initiation of discharge communication, and batching of phone calls were associated with improvements in our measures. Reliable verbal discharge communication can be achieved through the use of a standardized discharge communication process coupled with the EHR. © 2015 Society of Hospital Medicine.

  9. Effects of zinc supplementation on subscales of anorexia in children: A randomized controlled trial.

    Science.gov (United States)

    Khademian, Majid; Farhangpajouh, Neda; Shahsanaee, Armindokht; Bahreynian, Maryam; Mirshamsi, Mehran; Kelishadi, Roya

    2014-01-01

    This study aims to assess the effects of zinc supplementation on improving the appetite and its subscales in children. This study was conducted in 2013 in Isfahan, Iran. It had two phases. At the first step, after validation of the Child Eating Behaviour Questionaire (CEBQ), it was completed for 300 preschool children, who were randomly selected. The second phase was conducted as a randomized controlled trial. Eighty of these children were randomly selected, and were randomly assigned to two groups of equal number receiving zinc (10 mg/day) or placebo for 12 weeks. Overall 77 children completed the trial (39 in the case and 3 in the control group).The results showed that zinc supplement can improve calorie intake in children by affecting some CEBQ subscales like Emotional over Eating and Food Responsible. Zinc supplementation had positive impact in promoting the calorie intake and some subscales of anorexia.

  10. Ameliorating TCP congestion control for improving TCP reliability over wireless networks

    Science.gov (United States)

    Xu, Chang-biao; Long, Ke-ping; Xian, Yong-ju

    2004-04-01

    TCP congestion control mechanism, being based on the presupposition that network congestion is the only reason for data loss, is suitable for wired environments rather than for wireless environments with characteristics of higher bit error rate, lower bandwidth, longer delay, frequent mobility and so on, where link corruption can also cause data loss. To avoid unnecessary decrease of packet sending rate resulting in lower throughput and longer delay, some improved TCP congestion mechanisms have been presented. However, one of the disadvantages of these mechanisms is that a great deal of unnecessary packets lost by corruption can be caused while heavy data loss rate by corruption lasts short time. As well known, energy consumption of mobile hosts is one of the most important factors for wireless communication. How to save energy of mobile host has become an important task for wireless communication. One of the methods is to improve reliability to decrease overheads resulting from re-transmitting lost data. Obviously, it is necessary to decrease data sending rate, but how does it do? This paper answers the question, and then presents an improved TCP congestion control mechanism, namely TCP_IR (TCP for Improving Reliability) whose implementations are based on two algorithms. Algorithm I-based TCP_IR is driven by data sending periodic, while algorithm II-based TCP_IR is driven by the event of data lost by corruption. They can be very easily implemented with fewer overheads and can effectively improve TCP reliability with light influence to throughput and delay. The paper"s contribution is to give valuable references to further study TCP in wireless networks.

  11. A new approach for improving reliability of personal navigation devices under harsh GNSS signal conditions.

    Science.gov (United States)

    Dhital, Anup; Bancroft, Jared B; Lachapelle, Gérard

    2013-11-07

    In natural and urban canyon environments, Global Navigation Satellite System (GNSS) signals suffer from various challenges such as signal multipath, limited or lack of signal availability and poor geometry. Inertial sensors are often employed to improve the solution continuity under poor GNSS signal quality and availability conditions. Various fault detection schemes have been proposed in the literature to detect and remove biased GNSS measurements to obtain a more reliable navigation solution. However, many of these methods are found to be sub-optimal and often lead to unavailability of reliability measures, mostly because of the improper characterization of the measurement errors. A robust filtering architecture is thus proposed which assumes a heavy-tailed distribution for the measurement errors. Moreover, the proposed filter is capable of adapting to the changing GNSS signal conditions such as when moving from open sky conditions to deep canyons. Results obtained by processing data collected in various GNSS challenged environments show that the proposed scheme provides a robust navigation solution without having to excessively reject usable measurements. The tests reported herein show improvements of nearly 15% and 80% for position accuracy and reliability, respectively, when applying the above approach.

  12. Reliability of infarct volumetry: Its relevance and the improvement by a software-assisted approach.

    Science.gov (United States)

    Friedländer, Felix; Bohmann, Ferdinand; Brunkhorst, Max; Chae, Ju-Hee; Devraj, Kavi; Köhler, Yvette; Kraft, Peter; Kuhn, Hannah; Lucaciu, Alexandra; Luger, Sebastian; Pfeilschifter, Waltraud; Sadler, Rebecca; Liesz, Arthur; Scholtyschik, Karolina; Stolz, Leonie; Vutukuri, Rajkumar; Brunkhorst, Robert

    2017-08-01

    Despite the efficacy of neuroprotective approaches in animal models of stroke, their translation has so far failed from bench to bedside. One reason is presumed to be a low quality of preclinical study design, leading to bias and a low a priori power. In this study, we propose that the key read-out of experimental stroke studies, the volume of the ischemic damage as commonly measured by free-handed planimetry of TTC-stained brain sections, is subject to an unrecognized low inter-rater and test-retest reliability with strong implications for statistical power and bias. As an alternative approach, we suggest a simple, open-source, software-assisted method, taking advantage of automatic-thresholding techniques. The validity and the improvement of reliability by an automated method to tMCAO infarct volumetry are demonstrated. In addition, we show the probable consequences of increased reliability for precision, p-values, effect inflation, and power calculation, exemplified by a systematic analysis of experimental stroke studies published in the year 2015. Our study reveals an underappreciated quality problem in translational stroke research and suggests that software-assisted infarct volumetry might help to improve reproducibility and therefore the robustness of bench to bedside translation.

  13. ERP application of real-time vdc-enabled last planner system for planning reliability improvement

    DEFF Research Database (Denmark)

    Cho, S.; Sørensen, Kristian Birch; Fischer, M.

    2009-01-01

    The Last Planner System (LPS) has since its introduction in 1994 become a widely used method of AEC practitioners for improvement of planning reliability and tracking and monitoring of project progress. However, the observations presented in this paper indicate that the last planners and coordina......The Last Planner System (LPS) has since its introduction in 1994 become a widely used method of AEC practitioners for improvement of planning reliability and tracking and monitoring of project progress. However, the observations presented in this paper indicate that the last planners...... and coordinators are in need of a new system that integrates the existing LPS with Virtual Design and Construction (VDC), Enterprise Resource Planning (ERP) systems, and automatic object identification by means of Radio Frequency Identification (RFID) technology. This is because current practice of the LPS...... complete based weekly work plan and look ahead plan with product progress visualization based on programming intelligence. VREL allows LPS users to enable real-time information generating/sharing, more accurate and reliable planning, immediate proactive action execution, machine-to-machine process...

  14. Improving the Reliability of Technological Subsystems Equipment for Steam Turbine Unit in Operation

    Science.gov (United States)

    Brodov, Yu. M.; Murmansky, B. E.; Aronson, R. T.

    2017-11-01

    The authors’ conception is presented of an integrated approach to reliability improving of the steam turbine unit (STU) state along with its implementation examples for the various STU technological subsystems. Basing on the statistical analysis of damage to turbine individual parts and components, on the development and application of modern methods and technologies of repair and on operational monitoring techniques, the critical components and elements of equipment are identified and priorities are proposed for improving the reliability of STU equipment in operation. The research results are presented of the analysis of malfunctions for various STU technological subsystems equipment operating as part of power units and at cross-linked thermal power plants and resulting in turbine unit shutdown (failure). Proposals are formulated and justified for adjustment of maintenance and repair for turbine components and parts, for condenser unit equipment, for regeneration subsystem and oil supply system that permit to increase the operational reliability, to reduce the cost of STU maintenance and repair and to optimize the timing and amount of repairs.

  15. Measuring social skills of children and adolescents in a Chinese population: Preliminary evidence on the reliability and validity of the translated Chinese version of the Social Skills Improvement System-Rating Scales (SSIS-RS-C).

    Science.gov (United States)

    Cheung, Phoebe P P; Siu, Andrew M H; Brown, Ted

    2017-01-01

    The Social Skills Improvement System-Rating Scales (SSIS-RS; Gresham & Elliott, 2008) are designed to assist in the screening and classification of students (aged 5-18 years) who are suspected of presenting with social skills deficits and to offer guidelines in the development of interventions to remediate those types of problems. The objective of this study is to examine the preliminary reliability and validity of the translated Chinese version of the SSIS-RS, referred to as the SSIS-RS-C. In this study, parent-reported social skills and problem behaviors among students with typical development (n=79) were compared with those of age- and gender-matched students with a known developmental disability (n=79) using the SSIS-RS-C. The results indicated that the SSIS-RS-C subscale scores in all the disability groups were significantly different except for those in the Assertion scale for one disability group. Furthermore, the normative sample of typically developing children and adolescents (aged 5-12 and 13-18 years, n=567) from Hong Kong was established to improve the psychometric properties of the SSIS-RS-C. There were moderate to strong relationships between the common subscales across all forms of the SSIS-RS-C. Acceptable to excellent levels of internal consistency across all common subscales was also obtained. The scores for the Hong Kong sample (n=567) derived from the use of the SSIS-RS-C were then compared to the normative sample scores from the American version of the SSIS-RS. It was found that there were statistically significant differences on five out of the seven SSIS-RS-C Social Skill subscales for children aged 5-12 years and on four out of the seven SSIS-RS-C Social Skills subscales for the adolescent group (aged 13-18 years). Also, there were statistically significant differences between the American and Hong Kong samples on all of the SSIS-RS-C Problem Behavior scale scores. It was concluded that the SSIS-RS-C is a promising instrument for clinicians

  16. Reliability investigations and improvements of the pLEDMOS for PDP data driver ICs

    Science.gov (United States)

    Qian, Qinsong; Sun, Weifeng; Li, Haisong; Wu, Hong; Shi, Longxing

    2011-05-01

    In this paper, the p-type lateral extended drain MOS (pLEDMOS) transistor with thick gate oxide for plasma display panel (PDP) data driver ICs is developed. The following reliability issues have been discussed in detail: (1) hot-carrier degradation, (2) the contradiction between the parasitic bipolar junction transistor (BJT) punch-through phenomenon and the impurity segregation effect, (3) surface damage caused by the long-time diffusion process under high-temperature conditions, (4) creep behavior of the breakdown voltage and (5) the Kirk effect due to the high working current density. The improved methods for solving these reliability problems by optimizing the process and device architecture are also presented. The methods have also been verified by the technology computer-aided design (TCAD) simulations and experimental results.

  17. Reactive power control methods for improved reliability of wind power inverters under wind speed variations

    DEFF Research Database (Denmark)

    Ma, Ke; Liserre, Marco; Blaabjerg, Frede

    2012-01-01

    method to relieve the thermal cycling of power switching devices under severe wind speed variations, by circulating reactive power among the parallel power converters in a WTS or among the WTS's in a wind park. The amount of reactive power is adjusted to limit the junction temperature fluctuation......The thermal cycling of power switching devices may lead to failures that compromise the reliability of power converters. Wind Turbine Systems (WTS) are especially subject to severe thermal cycling which may be caused by the wind speed variations or power grid faults. This paper proposes a control...... temperature fluctuation in the most stressed devices of 3L-NPC wind power inverter under severe wind speed variations can be significantly stabilized, and the reliability of the power converter can thereby be improved while the increased stress of the other devices in the same power converter...

  18. Simplified skeletal maturity scoring system: learning curve and methods to improve reliability.

    Science.gov (United States)

    Verma, Kushagra; Sitoula, Prakash; Gabos, Peter; Loveland, Kerry; Sanders, James; Verma, Satyendra; Shah, Suken A

    2014-12-15

    Retrospective radiographical review by 5 independent observers. To validate the intra- and interobserver reliability of the simplified skeletal maturity scoring (SSMS) system in a large cohort for each stage and for the overall cohort. The SSMS has been used to successfully predict curve progression in idiopathic scoliosis. A total of 275 patients with scoliosis (8-16 yr) with 1 hand radiograph were included from 2005 to 2011. Five participants independently scored images on 2 separate occasions using the SSMS (stage, 1-8). Observers (listed in order of increasing SSMS experience) included orthopedic surgery resident, clinical fellow (CF), research fellow, and senior faculty. Intraobserver agreement between the 2 sets of scores was estimated using the Pearson and Spearman rank correlation coefficients. Interobserver agreement was estimated with the unweighted Fleiss κ coefficient for the overall cohort and for junior (orthopedic surgery resident, CF, research fellow) versus senior faculty. Intrarater reliability for orthopedic surgery resident, CF, research fellow, senior faculty was 0.956, 0.967, 0.986, 0.991, and 0.998, respectively (Spearman). Intrarater agreement improved with greater familiarity using the SSMS. The inter-rater reliability for junior faculty (κ = 0.65), senior faculty (κ = 0.652), and the overall group (κ = 0.66) indicated agreement between all observers but no improved inter-rater agreement with experience. However, 98% of disagreements occurred only within 1 stage. Stages 2, 3, and 4 accounted for most of the variability; stage 3 was the most commonly scored stage, corresponding to peak growth velocity. The SSMS has excellent intraobserver agreement with substantial interobserver agreement. Intraobserver--but not interobserver agreement--improves with familiarity using the SSMS. Expectancy bias may contribute to a higher likelihood of assigning an SSMS 3. Discrepancies when classifying stages 2 to 4 may be resolved by improved

  19. Validity and reliability of the Persian version of mobile phone addiction scale

    Directory of Open Access Journals (Sweden)

    Maryam Amidi Mazaheri

    2014-01-01

    Full Text Available Background: With regard to large number of mobile users especially among college students in Iran, addiction to mobile phone is attracting increasing concern. There is an urgent need for reliable and valid instrument to measure this phenomenon. This study examines validity and reliability of the Persian version of mobile phone addiction scale (MPAIS in college students. Materials and Methods: this methodological study was down in Isfahan University of Medical Sciences. One thousand one hundred and eighty students were selected by convenience sampling. The English version of the MPAI questionnaire was translated into Persian with the approach of Jones et al. (Challenges in language, culture, and modality: Translating English measures into American Sign Language. Nurs Res 2006; 55: 75-81. Its reliability was tested by Cronbach′s alpha and its dimensionality validity was evaluated using Pearson correlation coefficients with other measures of mobile phone use and IAT. Construct validity was evaluated using Exploratory subscale analysis. Results: Cronbach′s alpha of 0.86 was obtained for total PMPAS, for subscale1 (eight items was 0.84, for subscale 2 (five items was 0.81 and for subscale 3 (two items was 0.77. There were significantly positive correlations between the score of PMPAS and IAT (r = 0.453, P < 0.001 and other measures of mobile phone use. Principal component subscale analysis yielded a three-subscale structure including: inability to control craving; feeling anxious and lost; mood improvement accounted for 60.57% of total variance. The results of discriminate validity showed that all the item′s correlations with related subscale were greater than 0.5 and correlations with unrelated subscale were less than 0.5. Conclusion: Considering lack of a valid and reliable questionnaire for measuring addiction to the mobile phone, PMPAS could be a suitable instrument for measuring mobile phone addiction in future research.

  20. Validity and reliability of the Persian version of mobile phone addiction scale.

    Science.gov (United States)

    Mazaheri, Maryam Amidi; Karbasi, Mojtaba

    2014-02-01

    With regard to large number of mobile users especially among college students in Iran, addiction to mobile phone is attracting increasing concern. There is an urgent need for reliable and valid instrument to measure this phenomenon. This study examines validity and reliability of the Persian version of mobile phone addiction scale (MPAIS) in college students. this methodological study was down in Isfahan University of Medical Sciences. One thousand one hundred and eighty students were selected by convenience sampling. The English version of the MPAI questionnaire was translated into Persian with the approach of Jones et al. (Challenges in language, culture, and modality: Translating English measures into American Sign Language. Nurs Res 2006; 55: 75-81). Its reliability was tested by Cronbach's alpha and its dimensionality validity was evaluated using Pearson correlation coefficients with other measures of mobile phone use and IAT. Construct validity was evaluated using Exploratory subscale analysis. Cronbach's alpha of 0.86 was obtained for total PMPAS, for subscale1 (eight items) was 0.84, for subscale 2 (five items) was 0.81 and for subscale 3 (two items) was 0.77. There were significantly positive correlations between the score of PMPAS and IAT (r = 0.453, P < 0.001) and other measures of mobile phone use. Principal component subscale analysis yielded a three-subscale structure including: inability to control craving; feeling anxious and lost; mood improvement accounted for 60.57% of total variance. The results of discriminate validity showed that all the item's correlations with related subscale were greater than 0.5 and correlations with unrelated subscale were less than 0.5. Considering lack of a valid and reliable questionnaire for measuring addiction to the mobile phone, PMPAS could be a suitable instrument for measuring mobile phone addiction in future research.

  1. reliability reliability

    African Journals Online (AJOL)

    eobe

    addresses addresses: 1 idrcivil1@yahoo.com, 2 adomaarf1@gmail.com computer computer program was developed to aid the design of reinforced co program was developed to aid ... The probability-based design concept i. However, improvement on ... ian Journal of Technology (NIJOTECH). 4, October 2014, pp.436 – ...

  2. Mining protein interactomes to improve their reliability and support the advancement of network medicine

    KAUST Repository

    Alanis Lobato, Gregorio

    2015-09-23

    High-throughput detection of protein interactions has had a major impact in our understanding of the intricate molecular machinery underlying the living cell, and has permitted the construction of very large protein interactomes. The protein networks that are currently available are incomplete and a significant percentage of their interactions are false positives. Fortunately, the structural properties observed in good quality social or technological networks are also present in biological systems. This has encouraged the development of tools, to improve the reliability of protein networks and predict new interactions based merely on the topological characteristics of their components. Since diseases are rarely caused by the malfunction of a single protein, having a more complete and reliable interactome is crucial in order to identify groups of inter-related proteins involved in disease etiology. These system components can then be targeted with minimal collateral damage. In this article, an important number of network mining tools is reviewed, together with resources from which reliable protein interactomes can be constructed. In addition to the review, a few representative examples of how molecular and clinical data can be integrated to deepen our understanding of pathogenesis are discussed.

  3. An improved IEEE 802.11 protocol for reliable data transmission in power distribution fault diagnosis

    Energy Technology Data Exchange (ETDEWEB)

    Campoccia, F.; Di Silvestre, M.L.; Sanseverino, E.R.; Zizzo, G. [Palermo Univ., Palermo (Italy)

    2010-10-15

    In power systems, on-line transmission between local units and the central unit can be done by means of power line communications or wireless technology. During an electrical fault, the reliability of the distribution system depends on the security of the timely protective and restorative actions on the network. This paper focused on the WiFi system because of its economy and ease of installation. However, WiFi systems are typically managed by the IEEE 802.11 protocol, which is not reliable in terms of security in data communication. In WiFi networks, data is divided into packets and sent in succession to reduce errors within the radio channel. The IEEE 802.11 protocol has high probability for loss of packets or delay in their transmission. In order to ensure the reliability of data transmission times between two terminal units connected by WiFi stations, a new protocol was derived by modifying the IEEE 802.11. The improvements of the new protocol were highlighted and its capability for the diagnostic service was verified. The modified protocol eliminates the danger of collisions between packets and optimizes the transmission time for sending information. 6 refs., 7 tabs., 8 figs.

  4. Improving the reliability of clinical practice guideline appraisals: effects of the Korean AGREE II scoring guide.

    Science.gov (United States)

    Oh, Moo-Kyung; Jo, Heuisug; Lee, You Kyoung

    2014-06-01

    The Korean translated Appraisal of Guidelines for Research and Evaluation II (Korean AGREE II) instrument was distributed into Korean medical societies in 2011. However, inter-rater disagreement issues still exist. The Korean AGREE II scoring guide was therefore developed to reduce inter-rater differences. This study examines the effects of the Korean AGREE II scoring guide to reduce inter-rater differences. Appraisers were randomly assigned to two groups (Scoring Guide group and Non-Scoring Guide group). The Korean AGREE II instrument was provided to both groups. However, the scoring guide was offered to Scoring Guide group only. Total 14 appraisers were participated and each guideline was assessed by 8 appraisers. To evaluate the reliability of the Korean AGREE II scoring guide, correlation of scores among appraisers and domain-specific intra-class correlation (ICC) were compared. Most scores of two groups were comparable. Scoring Guide group showed higher reliability at all guidelines. They showed higher correlation among appraisers and higher ICC values at almost all domains. The scoring guide reduces the inter-rater disagreement and improves the overall reliability of the Korean-AGREE II instrument.

  5. Improving the reliability of peer-reviewed publications: We are all in it together

    Directory of Open Access Journals (Sweden)

    Stephen A. Bustin

    2016-03-01

    Full Text Available The current, and welcome, focus on standardization of techniques and transparency of reporting in the biomedical, peer-reviewed literature is commendable. However, that focus has been intermittent as well as lacklustre and so failed to tackle the alarming lack of reliability and reproducibly of biomedical research. Authors have access to numerous recommendations, ranging from simple standards dealing with technical issues to those regulating clinical trials, suggesting that improved reporting guidelines are not the solution. The elemental solution is for editors to require meticulous implementation of their journals’ instructions for authors and reviewers and stipulate that no paper is published without a transparent, complete and accurate materials and methods section.

  6. Reducing variability of workforce as a tool to improve plan reliability

    DEFF Research Database (Denmark)

    Wandahl, Søren; Yicheng, S.; Zygmunt, K. J.

    Variability of flow is recognized as the greatest obstacle to production management. Since the work flow and labour flow are two dominators of work performance, it is important to manage them simultaneously. The objective of this paper is to examine whether by reducing the variance of a labour flow......, a plan reliability can be improved, therefore, three different construction labour data sets have been examined by utilizing Monte Carlo Simulation, to analyze the probability to finish simulated projects within a certain time. The research findings revealed that reducing variance in the workforce flow...

  7. Reducing Variability of Workforce as a Tool to Improve Plan Reliability

    DEFF Research Database (Denmark)

    Yicheng, Shen; Zygmunt, Katarzyna Julia; Wandahl, Søren

    2017-01-01

    Variability of flow is recognized as one of the greatest obstacles to production management. Since the work flow and labour flow are two dominators of work performance, it is important to manage them simultaneously. The objective of this paper is to examine if an increased plan reliability could...... of the workforce flow does not necessarily shorten the project length, nevertheless it increases probability to finish the tasks within a critical path duration. Additionally, it was concluded, that reducing the variance of crew allocation can improve the productivity....

  8. Lecture 8: Data Reliability at CERN and Ideas on How to Improve it

    CERN Multimedia

    CERN. Geneva

    2013-01-01

    The talk will give an overview of data management activities at CERN focusing on the ongoing research activities aiming to improve data and service reliability. Alberto Pace is a member if the IT department at CERN where he leads the Data and Storage services group ensuring a coherent development process for Physics Data management activities, strongly driven by operational and user needs. He has more than 25 years experience in computing services, infrastructure, software engineering, accelerator control and accelerator operation. He graduated in Electronic Engineering from Politecnico di Milano (Italy).

  9. Robust and reliable rectifier based on electronic inductor with improved performance

    DEFF Research Database (Denmark)

    Singh, Yash Veer; Rasmussen, Peter Omand; Andersen, Torben Ole

    2014-01-01

    harmonic distortions (THDs) of the ac mains current in a three phase diode bridge rectifier. The ESI reduces the low frequency ripples and controls the intermediate dc-link voltage to a dc value and peak value of the mains current also reduces. In case of an inverter connected to the output......Reliability of a power converter depends on voltage and current stresses seen by power semiconductor devices during transient and steady state operation of the power converter. Electronic smoothing inductor (ESI) is an attractive circuit topology to improve power factor and to reduce the total...

  10. WAYS TO IMPROVE THE RELIABILITY AND OPERATING LIFE OF SMALL-SIZE ELECTROMAGNETIC VALVE

    Directory of Open Access Journals (Sweden)

    Gennadii Zaionchkovskyi

    2015-04-01

    Full Text Available This article considers the main ways of improving the reliability and durability of small-size electromagnetic valves. Major changes in the technical state of the valve components under dynamic operating loads were revealed using the results of resource tests of two-position valves with polarized electromagnetic actuator. Aneffective way for reducing the dynamic loads has proved to be the introduction of the damping element into the kinematic scheme of the electromagnetic valve actuator. Damping elements efficiency in reducing dynamic loads has been confirmed experimentally.

  11. Airspace Simulation Through Indoor Operation of Subscale Flight Vehicles Project

    Data.gov (United States)

    National Aeronautics and Space Administration — An indoor environment for simulating airspace operations will be designed. Highly maneuverable subscale vehicles can be used to simulate the dynamics of full-scale...

  12. Application of a method of welding for improvement of reliability of hoppers of slag carriages

    Directory of Open Access Journals (Sweden)

    Аркадій Васильович Лоза

    2016-07-01

    Full Text Available Reliability of the design of slag carriages is of great importance, as these belong to transportation system of iron and steel works, operating with enhanced danger due to the necessity to carry molten materials. That is why it is required to eliminate the slightest possibility of any failures of emergency situations at operation of slag carriages. Presence of defects in the hopper’s wall undermines its reliability and diminishes its service life. Hopper’s wall undergo at operation tremendous mechanical and thermal loads. Heating over the temperature range 500-600C º leads to appearance of residual deformations, it deteriorating exploitation conditions of a slag carrier. Overheating of separate sections of the casing can drastically deteriorate strength characteristics of the material, specified for the hopper’s design. This leads to alternations of its original geometry. The existing methods of improvement of its strength are insufficient due to economic and technological reasons. For this reason a technical solution was proposed and tested, in which additional reinforcing ribs to be installed above the deformation area on the side surface of the hopper were presumed. The indicted area is characterized by the smallest heating temperature its exploitation temperature possesses higher strength characteristics than other sections. This feature was used for strengthening of a less strong adjoining deformation area, undergoing high heating temperature. Reinforcing ribs are made by foundry methods do not always ensure the desired effect as they present the source of inner defects and formation of cracks. This is explained by formation of heat centres and T-shaped elements of casting, that are last crystallized and have no dense structure. That is why it was proposed to install welded reinforcing ribs for improved design of a slag carriers. The ribs are to be manufactured of steel rolled stock. This variant of installation of additional

  13. Active Thermal Control for Reliability Improvement of MOS-gated Power Devices

    DEFF Research Database (Denmark)

    Soldati, Alessandro; Concari, Carlo; Dossena, Fabrizio

    2017-01-01

    This paper proposes an Active Thermal Control (ATC) method for MOS-gated power switches aimed at reducing temperature swing amplitude during operation. It leverages on the fact that thermal cycle amplitude of many actuation system components (such as power devices) has a large impact on the system...... reliability and lifetime. These figures can then be improved, which eases the adoption of electrification in markets, such as transportation, where they are still below target values. The proposed ATC method leaves electric load parameters untouched, while acting dynamically on gate parameters, namely voltage...... and resistance. A model-predictive control (MPC) strategy is used to determine the most suitable parameters to use. Simulations of the control scheme are presented first, to predict the potential benefits on temperature swing amplitude, and the consequent improvements in terms of device lifetime are inferred...

  14. Bales's Interpersonal Rating Forms: Reliability and Dimensionality.

    Science.gov (United States)

    Lustig, Myron W.

    1987-01-01

    Investigated reliability and dimensionality of Bales's Interpersonal Rating Forms (IRF) using volunteer subjects (N=266) enrolled in undergraduate communications course. Results documented shortcomings of IRF as a measuring instrument finding the subscales neither reliable nor dimensionally structured; only 2 of 18 items in each subscale are…

  15. Confirmatory Factor Analysis of the PKBS-2 Subscales for Assessing Social Skills and Behavioral Problems in Preschool Education

    Science.gov (United States)

    Fernandez, Maria; Benitez, Juan L.; Pichardo, M. Carmen; Fernandez, Eduardo; Justicia, Fernando; Garcia, Trinidad; Garcia-Berben, Ana; Justicia, Ana; Alba, Guadalupe

    2010-01-01

    Introduction: Different research studies point out the importance of social competence as a protective factor against antisocial behavior. They likewise alert us of the importance of having valid, reliable instruments that measure these constructs in early childhood. Method: The objective of this research is to validate the subscales of the…

  16. Control Strategies for Improving Energy Efficiency and Reliability in Autonomous Microgrids with Communication Constraints

    Directory of Open Access Journals (Sweden)

    Francisco Martins Portelinha Júnior

    2017-09-01

    Full Text Available Microgrids are a feasible path to deploy smart grids, an intelligent and highly automated power system. Their operation demands a dedicated communication infrastructure to manage, control and monitor the intermittent sources of energy and loads. Therefore, smart devices will be connected to support the growth of grid smartness increasing the dependency on communication networks, which consumes a high amount of power. In an energy-limited scenario, one of the main issues is to enhance the power supply time. Therefore, this paper proposes a hybrid methodology for microgrid energy management, integrated with a communication infrastructure to improve and to optimize islanded microgrid operation at maximum energy efficiency. The hybrid methodology applies some control management rules, such as intentional load shedding, priority load management, and communication energy saving. These energy saving rules establish a trade-off between increasing microgrid energy availability and communication system reliability. To achieve a compromised solution, a continuous time Markov chain model describes the impact of energy saving policies into system reliability. The proposed methodology is simulated and tested with the help of the modified IEEE 34 node test-system.

  17. Improving the reliability of single-subject fMRI by weighting intra-run variability.

    Science.gov (United States)

    de Bertoldi, F; Finos, L; Maieron, M; Weis, L; Campanella, M; Ius, T; Fadiga, L

    2015-07-01

    At present, functional magnetic resonance imaging (fMRI) is one of the most useful methods of studying cognitive processes in the human brain in vivo, both for basic science and clinical goals. Although neuroscience studies often rely on group analysis, clinical applications must investigate single subjects (patients) only. Particularly for the latter, issues regarding the reliability of fMRI readings remain to be resolved. To determine the ability of intra-run variability (IRV) weighting to consistently detect active voxels, we first acquired fMRI data from a sample of healthy subjects, each of whom performed 4 runs (4 blocks each) of self-paced finger-tapping. Each subject's data was analyzed using single-run general linear model (GLM), and each block was then analyzed separately to calculate the IRV weighting. Results show that integrating IRV information into standard single-subject GLM activation maps significantly improved the reliability (p=0.007) of the single-subject fMRI data. This suggests that taking IRV into account can help identify the most constant and relevant neuronal activity at the single-subject level. Copyright © 2015. Published by Elsevier Inc.

  18. Metal-Matrix Nanocomposites with Tailored Coefficients of Thermal Expansion for Improved Thermomechanical Reliability

    Science.gov (United States)

    Trujillo, J. E.; Kim, J. W.; Lan, E. H.; Sharratt, S.; Ju, Y. S.; Dunn, B.

    2012-06-01

    Ensuring the thermomechanical reliability of various interfaces in thermoelectric (TE) devices during manufacture and operation is challenging, especially for those incorporating TE materials with small coefficients of thermal expansion (CTEs). In this paper, we describe our recent progress in the development of metal-matrix nanocomposites with tailorable CTEs, for use as electrodes or as interfacial bonding layers for creating segmented TE elements. The composites incorporate ceramic nanoscale fillers with isotropic negative thermal expansion (NTE) to effectively offset the high CTE of the metal phase. The NTE fillers, synthesized using a sol-gel route, were mixed with metal powders and hot pressed to yield nanocomposites having CTE values decreasing approximately linearly with filler volume fraction. Composites with 54/46 v/v Ag/zirconium tungstate (ZrW2O8) achieved average CTE of 7.2 ppm/K, with electrical and thermal conductivities approximately 50% of that of Ag nanopowders hot pressed under identical conditions. X-ray diffraction (XRD) analyses suggest that the composites are thermally stable at temperatures as high as 920 K. This research provides a foundation upon which to investigate alternative electrode and interface materials with tailored CTEs for achieving improved thermomechanical reliability of TE modules and other thermal and electronic devices.

  19. Improved Reliability of Small Molecule Organic Solar Cells by Double Anode Buffer Layers

    Directory of Open Access Journals (Sweden)

    Pao-Hsun Huang

    2014-01-01

    Full Text Available An optimized hybrid planar heterojunction (PHJ of small molecule organic solar cells (SM-OSCs based on copper phthalocyanine (CuPc as donor and fullerene (C60 as acceptor was fabricated, which obviously enhanced the performance of device by sequentially using both MoO3 and pentacene as double anode buffer layers (ABL, also known as hole extraction layer (HEL. A series of the vacuum-deposited ABL, acting as an electron and exciton blocking layer, were examined for their characteristics in SM-OSCs. The performance and reliability were compared between conventional ITO/ABL/CuPc/C60/BCP/Ag cells and the new ITO/double ABL/CuPc/C60/BCP/Ag cells. The effect on the electrical properties of these materials was also investigated to obtain the optimal thickness of ABL. The comparison shows that the modified cell has an enhanced reliability compared to traditional cells. The improvement of lifetime was attributed to the idea of double layers to prevent humidity and oxygen from diffusing into the active layer. We demonstrated that the interfacial extraction layers are necessary to avoid degradation of device. That is to say, in normal temperature and pressure, a new avenue for the device within double buffer layers has exhibited the highest values of open circuit voltage (Voc, fill factor (FF, and lifetime in this work compared to monolayer of ABL.

  20. [Examination of safety improvement by failure record analysis that uses reliability engineering].

    Science.gov (United States)

    Kato, Kyoichi; Sato, Hisaya; Abe, Yoshihisa; Ishimori, Yoshiyuki; Hirano, Hiroshi; Higashimura, Kyoji; Amauchi, Hiroshi; Yanakita, Takashi; Kikuchi, Kei; Nakazawa, Yasuo

    2010-08-20

    How the maintenance checks of the medical treatment system, including start of work check and the ending check, was effective for preventive maintenance and the safety improvement was verified. In this research, date on the failure of devices in multiple facilities was collected, and the data of the trouble repair record was analyzed by the technique of reliability engineering. An analysis of data on the system (8 general systems, 6 Angio systems, 11 CT systems, 8 MRI systems, 8 RI systems, and the radiation therapy system 9) used in eight hospitals was performed. The data collection period assumed nine months from April to December 2008. Seven items were analyzed. (1) Mean time between failures (MTBF) (2) Mean time to repair (MTTR) (3) Mean down time (MDT) (4) Number found by check in morning (5) Failure generation time according to modality. The classification of the breakdowns per device, the incidence, and the tendency could be understood by introducing reliability engineering. Analysis, evaluation, and feedback on the failure generation history are useful to keep downtime to a minimum and to ensure safety.

  1. Toward lean satellites reliability improvement using HORYU-IV project as case study

    Science.gov (United States)

    Faure, Pauline; Tanaka, Atomu; Cho, Mengu

    2017-04-01

    Lean satellite programs are programs in which the satellite development philosophy is driven by fast delivery and low cost. Though this concept offers the possibility to develop and fly risky missions without jeopardizing a space program, most of these satellites suffer infant mortality and fail to achieve their mission minimum success. Lean satellites with high infant mortality rate indicate that testing prior to launch is insufficient. In this study, the authors monitored failures occurring during the development of the lean satellite HORYU-IV to identify the evolution of the cumulative number of failures against cumulative testing time. Moreover, the sub-systems driving the failures depending on the different development phases were identified. The results showed that half to 2/3 of the failures are discovered during the early stage of testing. Moreover, when the mean time before failure was calculated, it appeared that for any development phase considered, a new failure appears on average every 20 h of testing. Simulations were also performed and it showed that for an initial testing time of 50 h, reliability after 1 month launch can be improved by nearly 6 times as compared to an initial testing time of 20 h. Through this work, the authors aim at providing a qualitative reference for lean satellites developers to better help them manage resources to develop lean satellites following a fast delivery and low cost philosophy while ensuring sufficient reliability to achieve mission minimum success.

  2. A Smart Checkpointing Scheme for Improving the Reliability of Clustering Routing Protocols

    Directory of Open Access Journals (Sweden)

    Jiman Hong

    2010-09-01

    Full Text Available In wireless sensor networks, system architectures and applications are designed to consider both resource constraints and scalability, because such networks are composed of numerous sensor nodes with various sensors and actuators, small memories, low-power microprocessors, radio modules, and batteries. Clustering routing protocols based on data aggregation schemes aimed at minimizing packet numbers have been proposed to meet these requirements. In clustering routing protocols, the cluster head plays an important role. The cluster head collects data from its member nodes and aggregates the collected data. To improve reliability and reduce recovery latency, we propose a checkpointing scheme for the cluster head. In the proposed scheme, backup nodes monitor and checkpoint the current state of the cluster head periodically. We also derive the checkpointing interval that maximizes reliability while using the same amount of energy consumed by clustering routing protocols that operate without checkpointing. Experimental comparisons with existing non-checkpointing schemes show that our scheme reduces both energy consumption and recovery latency.

  3. Improved techniques to monitor thin film characteristics for reliable hybrid microcircuit fabrication

    Energy Technology Data Exchange (ETDEWEB)

    Zawicki, L.R.; Thomas, N.C.

    1980-06-01

    The development, testing, and uses of an edge monitor for monitoring the characteristics of thin metallic films used in the fabrication of hybrid microcircuits are described. The data obtained on this quality control equipment demonstrated improved techniques for monitoring thin film characteristics for reliable hybrid microcircuit fabrication. This was accomplished through the design of a specialized circuit, an integral part of the product substrate to be tested that enhances the effects of degradation mechanisms, both mechanically and electrically. Correlation of mechanical and/or physical characteristcs with electrical data was demonstrated. When coupled with a minicomputer test set with controlling and data retention capabilities, the system offers a useful tool for production process monitoring, diagnostic evaluation, or developmental efforts. (LCL)

  4. Upgrades to improve the usability, reliability, and spectral range of the MST Thomson scattering diagnostic

    Science.gov (United States)

    Kubala, S. Z.; Borchardt, M. T.; Den Hartog, D. J.; Holly, D. J.; Jacobson, C. M.; Morton, L. A.; Young, W. C.

    2016-11-01

    The Thomson scattering diagnostic on MST records both equilibrium and fluctuating electron temperature with a range capability of 10 eV-5 keV. Standard operation with two modified commercial Nd:YAG lasers allows measurements at rates of 1 kHz-25 kHz. Several subsystems of the diagnostic are being improved. The power supplies for the avalanche photodiode detectors (APDs) that record the scattered light are being replaced to improve usability, reliability, and maintainability. Each of the 144 APDs will have an individual rack mounted switching supply, with bias voltage adjustable to match the APD. Long-wavelength filters (1140 nm center, 80 nm bandwidth) have been added to the polychromators to improve capability to resolve non-Maxwellian distributions and to enable directed electron flow measurements. A supercontinuum (SC) pulsed white light source has replaced the tungsten halogen lamp previously used for spectral calibration of the polychromators. The SC source combines substantial brightness produced in nanosecond pulses with a spectrum that covers the entire range of the polychromators.

  5. Improving the Test-Retest Reliability of Resting State fMRI by Removing the Impact of Sleep.

    Science.gov (United States)

    Wang, Jiahui; Han, Junwei; Nguyen, Vinh T; Guo, Lei; Guo, Christine C

    2017-01-01

    Resting state functional magnetic resonance imaging (rs-fMRI) provides a powerful tool to examine large-scale neural networks in the human brain and their disturbances in neuropsychiatric disorders. Thanks to its low demand and high tolerance, resting state paradigms can be easily acquired from clinical population. However, due to the unconstrained nature, resting state paradigm is associated with excessive head movement and proneness to sleep. Consequently, the test-retest reliability of rs-fMRI measures is moderate at best, falling short of widespread use in the clinic. Here, we characterized the effect of sleep on the test-retest reliability of rs-fMRI. Using measures of heart rate variability (HRV) derived from simultaneous electrocardiogram (ECG) recording, we identified portions of fMRI data when subjects were more alert or sleepy, and examined their effects on the test-retest reliability of functional connectivity measures. When volumes of sleep were excluded, the reliability of rs-fMRI is significantly improved, and the improvement appears to be general across brain networks. The amount of improvement is robust with the removal of as much as 60% volumes of sleepiness. Therefore, test-retest reliability of rs-fMRI is affected by sleep and could be improved by excluding volumes of sleepiness as indexed by HRV. Our results suggest a novel and practical method to improve test-retest reliability of rs-fMRI measures.

  6. Improving the Test-Retest Reliability of Resting State fMRI by Removing the Impact of Sleep

    Directory of Open Access Journals (Sweden)

    Jiahui Wang

    2017-05-01

    Full Text Available Resting state functional magnetic resonance imaging (rs-fMRI provides a powerful tool to examine large-scale neural networks in the human brain and their disturbances in neuropsychiatric disorders. Thanks to its low demand and high tolerance, resting state paradigms can be easily acquired from clinical population. However, due to the unconstrained nature, resting state paradigm is associated with excessive head movement and proneness to sleep. Consequently, the test-retest reliability of rs-fMRI measures is moderate at best, falling short of widespread use in the clinic. Here, we characterized the effect of sleep on the test-retest reliability of rs-fMRI. Using measures of heart rate variability (HRV derived from simultaneous electrocardiogram (ECG recording, we identified portions of fMRI data when subjects were more alert or sleepy, and examined their effects on the test-retest reliability of functional connectivity measures. When volumes of sleep were excluded, the reliability of rs-fMRI is significantly improved, and the improvement appears to be general across brain networks. The amount of improvement is robust with the removal of as much as 60% volumes of sleepiness. Therefore, test-retest reliability of rs-fMRI is affected by sleep and could be improved by excluding volumes of sleepiness as indexed by HRV. Our results suggest a novel and practical method to improve test-retest reliability of rs-fMRI measures.

  7. SPE5 Sub-Scale Test Series Summary Report

    Energy Technology Data Exchange (ETDEWEB)

    Vandersall, Kevin S. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Reeves, Robert V. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); DeHaven, Martin R. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Strickland, Shawn L. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2016-01-14

    A series of 2 SPE5 sub-scale tests were performed to experimentally confirm that a booster system designed and evaluated in prior tests would properly initiate the PBXN-110 case charge fill. To conduct the experiments, a canister was designed to contain the nominally 50 mm diameter booster tube with an outer fill of approximately 150 mm diameter by 150 mm in length. The canisters were filled with PBXN-110 at NAWS-China Lake and shipped back to LLNL for testing in the High Explosives Applications Facility (HEAF). Piezoelectric crystal pins were placed on the outside of the booster tube before filling, and a series of piezoelectric crystal pins along with Photonic Doppler Velocimetry (PDV) probes were placed on the outer surface of the canister to measure the relative timing and magnitude of the detonation. The 2 piezoelectric crystal pins integral to the booster design were also utilized along with a series of either piezoelectric crystal pins or piezoelectric polymer pads on the top of the canister or outside case that utilized direct contact, gaps, or different thicknesses of RTV cushions to obtain time of arrival data to evaluate the response in preparation for the large-scale SPE5 test. To further quantify the margin of the booster operation, the 1st test (SPE5SS1) was functioned with both detonators and the 2nd test (SPE5SS2) was functioned with only 1 detonator. A full detonation of the material was observed in both experiments as observed by the pin timing and PDV signals. The piezoelectric pads were found to provide a greater measured signal magnitude during the testing with an RTV layer present, and the improved response is due to the larger measurement surface area of the pad. This report will detail the experiment design, canister assembly for filling, final assembly, experiment firing, presentation of the diagnostic results, and a discussion of the results.

  8. Reliability improvement of electronic circuits based on physical failure mechanisms in components

    NARCIS (Netherlands)

    Brombacher, A.C.; de Boer, H.A.; Bennion, M.; Fennema, P.H.; Hermann, O.E.

    1991-01-01

    Traditionally the position of reliability analysis in the design and production process of electronic circuits is a position of reliability verification. A completed design is checked on reliability aspects and either rejected or accepted for production. This paper describes a method to model

  9. An Innovative Excel Application to Improve Exam Reliability in Marketing Courses

    Science.gov (United States)

    Keller, Christopher M.; Kros, John F.

    2011-01-01

    Measures of survey reliability are commonly addressed in marketing courses. One statistic of reliability is "Cronbach's alpha." This paper presents an application of survey reliability as a reflexive application of multiple-choice exam validation. The application provides an interactive decision support system that incorporates survey item…

  10. Carbohydrate ingestion improves performance of a new reliable test of soccer performance.

    Science.gov (United States)

    Currell, Kevin; Conway, Steve; Jeukendrup, Asker E

    2009-02-01

    The aim of the study was to investigate the reliability of a new test of soccer performance and evaluate the effect of carbohydrate (CHO) on soccer performance. Eleven university footballers were recruited and underwent 3 trials in a randomized order. Two of the trials involved ingesting a placebo beverage, and the other, a 7.5% maltodextrin solution. The protocol comprised a series of ten 6-min exercise blocks on an outdoor Astroturf pitch, separated by the performance of 2 of the 4 soccer-specific tests, making the protocol 90 min in duration. The intensity of the exercise was designed to be similar to the typical activity pattern during soccer match play. Participants performed skill tests of dribbling, agility, heading, and shooting throughout the protocol. The coefficients of variation for dribbling, agility, heading, and shooting were 2.2%, 1.2%, 7.0%, and 2.8%, respectively. The mean combined placebo scores were 42.4 +/- 2.7 s, 43.1 +/- 3.7 s, 210 +/- 34 cm, and 212 +/- 17 points for agility, dribbling, heading, and kicking, respectively. CHO ingestion led to a combined agility time of 41.5 +/- 0.8 s, for dribbling 41.7 +/- 3.5 s, 213 +/- 11 cm for heading, and 220 +/- 5 points for kicking accuracy. There was a significant improvement in performance for dribbling, agility, and shooting (p soccer performance, and ingesting CHO leads to an improvement in soccer performance.

  11. Improved resistive switching reliability by using dual-layer nanoporous carbon structure

    Science.gov (United States)

    Tao, Ye; Li, Xuhong; Wang, Zhongqiang; Xu, Haiyang; Ding, Wentao; Ma, Jiangang; Liu, Yichun

    2017-10-01

    We optimized the diameter and microgeometry of preformed conductive filaments (CFs) to improve the switching reliability of copper/nanoporous amorphous carbon (a-C)/platinum memory devices. Forming-free devices were obtained because of the introduction of preformed CFs into the nanoporous layer during the copper electrode evaporation process. The switching fluctuation decreased with the increasing preformed CF size in a certain range; however, the device with stronger preformed CFs suffered from high current in the first RESET process. Furthermore, to achieve both high switching uniformity and low power consumption, a dual-layer structure was proposed to regulate the microgeometry of preformed CFs. Compared with those of a pristine device and single-layer nanoporous device, the fluctuation of high/low resistance values was further suppressed to 26% and 21%, respectively. In addition, Resistive random access memory (RRAM) devices exhibited a fast switching speed (105 cycles), and long retention time (>105 s at 85 °C). These results reveal the key role of preformed CF optimization in resistive switching performance improvement, providing an effective approach to develop high-performance RRAM devices.

  12. Improved reliability, accuracy and quality in automated NMR structure calculation with ARIA

    Energy Technology Data Exchange (ETDEWEB)

    Mareuil, Fabien [Institut Pasteur, Cellule d' Informatique pour la Biologie (France); Malliavin, Thérèse E.; Nilges, Michael; Bardiaux, Benjamin, E-mail: bardiaux@pasteur.fr [Institut Pasteur, Unité de Bioinformatique Structurale, CNRS UMR 3528 (France)

    2015-08-15

    In biological NMR, assignment of NOE cross-peaks and calculation of atomic conformations are critical steps in the determination of reliable high-resolution structures. ARIA is an automated approach that performs NOE assignment and structure calculation in a concomitant manner in an iterative procedure. The log-harmonic shape for distance restraint potential and the Bayesian weighting of distance restraints, recently introduced in ARIA, were shown to significantly improve the quality and the accuracy of determined structures. In this paper, we propose two modifications of the ARIA protocol: (1) the softening of the force field together with adapted hydrogen radii, which is meaningful in the context of the log-harmonic potential with Bayesian weighting, (2) a procedure that automatically adjusts the violation tolerance used in the selection of active restraints, based on the fitting of the structure to the input data sets. The new ARIA protocols were fine-tuned on a set of eight protein targets from the CASD–NMR initiative. As a result, the convergence problems previously observed for some targets was resolved and the obtained structures exhibited better quality. In addition, the new ARIA protocols were applied for the structure calculation of ten new CASD–NMR targets in a blind fashion, i.e. without knowing the actual solution. Even though optimisation of parameters and pre-filtering of unrefined NOE peak lists were necessary for half of the targets, ARIA consistently and reliably determined very precise and highly accurate structures for all cases. In the context of integrative structural biology, an increasing number of experimental methods are used that produce distance data for the determination of 3D structures of macromolecules, stressing the importance of methods that successfully make use of ambiguous and noisy distance data.

  13. Subscale Water Based Phase Change Material Heat Exchanger Development

    Science.gov (United States)

    Sheth, Rubik; Hansen, Scott

    2016-01-01

    Supplemental heat rejection devices are required in many spacecraft as the radiators are not sized to meet the full heat rejection demand. One means of obtaining additional heat rejection is through the use of phase change material heat exchangers (PCM HX's). PCM HX's utilize phase change to store energy in unfavorable thermal environments (melting) and reject the energy in favorable environments (freezing). Traditionally, wax has been used as a PCM on spacecraft. However, water is an attractive alternative because it is capable of storing about 40% more energy per unit mass due to its higher latent heat of fusion. The significant problem in using water as a PCM is its expansion while freezing, leading to structural integrity concerns when housed in an enclosed heat exchanger volume. Significant investigation and development has taken place over the past five years to understand and overcome the problems associated with water PCM HX's. This paper reports on the final efforts by Johnson Space Center's Thermal Systems Branch to develop a water based PCM HX. The test article developed and reported on is a subscale version of the full-scale water-based PCM HX's constructed by Mezzo Technologies. The subscale unit was designed by applying prior research on freeze front propagation and previous full-scale water PCM HX development. Design modifications to the subscale unit included use of urethane bladder, decreased aspect ratio, perforated protection sheet, and use of additional mid-plates. Testing of the subscale unit was successful and 150 cycles were completed without fail.

  14. What the Customer Wants. Maintenance-Free and Failure-Free Operating Periods to Improve Overall System Availability and Reliability

    Science.gov (United States)

    2000-09-01

    UNCLASSIFIED Defense Technical Information Center Compilation Part Notice ADP010429 TITLE: What the Customer Wants. Maintenance-Free and Failure-Free... THE CUSTOMER WANTS MAINTENANCE-FREE AND FAILURE-FREE OPERATING PERIODS TO IMPROVE OVERALL SYSTEM AVAILABILITY AND RELIABILITY SQUADRON LEADER P MITCHELL...form part of a proposal from an equipment supplier. product reliability, in order to provide the customer with Vendors may then typically estimate

  15. Improved reliability of the urine lactate concentration under controlled hydration after maximal exercise.

    Science.gov (United States)

    Nikolaidis, Stefanos; Kosmidis, Ioannis; Koulidou, Triantafullia; Panagakis, Sotiris; Tsalis, George; Loupos, Dimitris; Mougios, Vassilis

    2017-11-01

    Urine lactate may be a novel biomarker of lactate production capacity but its reliability has been unsatisfactory so far. To compare the reliability of urine lactate between controlled hydration and no hydration after maximal exercise. Athletes performed swimming exercise four times: two followed by consumption of 1 L of water and two followed by no water intake. Blood and urine lactate was measured. The reliability of urine lactate was good and similar to that in blood only after controlled hydration. Blood and urine lactate were correlated under both hydration conditions. Controlled hydration after exercise provides satisfactory reliability of urine lactate.

  16. Embedded Sensors and Controls to Improve Component Performance and Reliability: Conceptual Design Report

    Energy Technology Data Exchange (ETDEWEB)

    Kisner, Roger A [ORNL; Melin, Alexander M [ORNL; Burress, Timothy A [ORNL; Fugate, David L [ORNL; Holcomb, David Eugene [ORNL; Wilgen, John B [ORNL; Miller, John M [ORNL; Wilson, Dane F [ORNL; Silva, Pamela C [ORNL; Whitlow, Lynsie J [ORNL; Peretz, Fred J [ORNL

    2012-10-01

    The overall project objective is to demonstrate improved reliability and increased performance made possible by deeply embedding instrumentation and controls (I&C) in nuclear power plant components. The project is employing a highly instrumented canned rotor, magnetic bearing, fluoride salt pump as its I&C technology demonstration vehicle. The project s focus is not primarily on pump design, but instead is on methods to deeply embed I&C within a pump system. However, because the I&C is intimately part of the basic millisecond-by-millisecond functioning of the pump, the I&C design cannot proceed in isolation from the other aspects of the pump. The pump will not function if the characteristics of the I&C are not embedded within the design because the I&C enables performance of the basic function rather than merely monitoring quasi-stable performance. Traditionally, I&C has been incorporated in nuclear power plant (NPP) components after their design is nearly complete; adequate performance was obtained through over-design. This report describes the progress and status of the project and provides a conceptual design overview for the embedded I&C pump.

  17. Virtualization of Legacy Instrumentation Control Computers for Improved Reliability, Operational Life, and Management.

    Science.gov (United States)

    Katz, Jonathan E

    2017-01-01

    Laboratories tend to be amenable environments for long-term reliable operation of scientific measurement equipment. Indeed, it is not uncommon to find equipment 5, 10, or even 20+ years old still being routinely used in labs. Unfortunately, the Achilles heel for many of these devices is the control/data acquisition computer. Often these computers run older operating systems (e.g., Windows XP) and, while they might only use standard network, USB or serial ports, they require proprietary software to be installed. Even if the original installation disks can be found, it is a burdensome process to reinstall and is fraught with "gotchas" that can derail the process-lost license keys, incompatible hardware, forgotten configuration settings, etc. If you have running legacy instrumentation, the computer is the ticking time bomb waiting to put a halt to your operation.In this chapter, I describe how to virtualize your currently running control computer. This virtualized computer "image" is easy to maintain, easy to back up and easy to redeploy. I have used this multiple times in my own lab to greatly improve the robustness of my legacy devices.After completing the steps in this chapter, you will have your original control computer as well as a virtual instance of that computer with all the software installed ready to control your hardware should your original computer ever be decommissioned.

  18. Ambipolarity reduction in DMG asymmetric vacuum dielectric Schottky Barrier GAA MOSFET to improve hot carrier reliability

    Science.gov (United States)

    Kumar, Manoj; Haldar, Subhasis; Gupta, Mridula; Gupta, R. S.

    2017-11-01

    An explicit surface potential and subthreshold current model for novel Dual Metal Gate (DMG) Asymmetric Vacuum (AV) as gate dielectric Schottky Barrier (SB) Cylindrical Gate All Around (CGAA) MOSFET with the incorporation of localized charges (Nf) is developed to provide excellent immunity against threshold voltage (Vth) degradation due to hot carriers. Hot carrier induced Localized Charges (LC) either positive or negative leads to degrade the threshold of the device. The major advantage of the proposed DMG-AV-SB-CGAA MOSFET is that it mitigates the ambipolar behavior thus offering very good on current to off current ratio; and also reduces the electron temperature which leads to less hot carrier generation thus lesser degradation in Vth and improved Hot Carrier reliability. The surface potential is determined for three different regions by solving 1-D Poisson's and 2-D Laplace equation through separation of variable method to facilitate an optimal model for calculating the subthreshold drain current from Si-SiO2 interface boundary. The developed model results are in good agreement with that of ATLAS-TCAD simulation.

  19. An analysis of implantable cardiac device reliability. The case for improved postmarketing risk assessment and surveillance.

    Science.gov (United States)

    Laskey, Warren; Awad, Khaled; Lum, Jeremy; Skodacek, Ken; Zimmerman, Barbara; Selzman, Kimberly; Zuckerman, Bram

    2012-07-01

    Implantable cardiac devices have become the mainstay of the treatment of patients with heart disease. However, data regarding their reliability and, inferentially, safety have been called into question. We reviewed annual reports submitted to the Food and Drug Administration Office of Device Evaluation by device manufacturers from 2003 to 2007. The annual number of implantable cardiac defibrillators (ICDs) and cardiac resynchronization therapy defibrillator (CRT-D) implants, explants, and returned devices were tabulated along with the cumulative (Cum) number of implants for each device. We derived an annual explantation rate (AER) defined as the ratio of the annual number of explants less the number of normal battery depletions/Cum (×1000). From 2003 to 2007, 256,392 CRT-D and 459,300 ICD devices were implanted in the United States. The overall mean (±SD) AERs for ICD and CRT-D devices were, respectively, 49.5 (15.6) per 1000 ICD devices and 82.6 (35.5) per 1000 CRT-D devices. The AER for each device type significantly decreased over the study period (P for trend AER for CRT-D devices was 38% higher than that for ICD devices (P AER for CRT-D devices was higher than that for ICD devices. Improved methods for tracking individual device histories are needed for more precise estimates of the risk of device explantation for suspected malfunction. The proportion of devices returned to the manufacturer is suboptimal and needs to be improved to better understand the mechanisms of device malfunction.

  20. Improving accuracy of overhanging structures for selective laser melting through reliability characterization of single track formation on thick powder beds

    DEFF Research Database (Denmark)

    Mohanty, Sankhya; Hattel, Jesper Henri

    2016-01-01

    establishing reliability of overhanging structure production by selective laser melting has been adopted. A calibrated, fast, multiscale thermal model is used to simulate the single track formation on a thick powder bed. Single tracks are manufactured on a thick powder bed using same processing parameters......, and subjected to uncertainty and reliability analysis. Cumulative probability distribution functions obtained for melt track widths and depths are found to be coherent with observed experimental values. The technique is subsequently extended for reliability characterization of single layers produced on a thick...... modelling has been adopted towards improving the predictability of the outputs from the selective laser melting process. Establishing the reliability of the process, however, is still a challenge, especially in components having overhanging structures.In this paper, a systematic approach towards...

  1. Subscale Acoustic Testing: Comparison of ALAT and ASMAT

    Science.gov (United States)

    Houston, Janice D.; Counter, Douglas

    2014-01-01

    The liftoff phase induces acoustic loading over a broad frequency range for a launch vehicle. These external acoustic environments are then used in the prediction of internal vibration responses of the vehicle and components which result in the qualification levels. Thus, predicting these liftoff acoustic environments is critical to the design requirements of any launch vehicle. If there is a significant amount of uncertainty in the predictions or if acoustic mitigation options must be implemented, a subscale acoustic test is a feasible pre-launch test option. This paper compares the acoustic measurements of two different subscale tests: the 2% Ares Liftoff Acoustic Test conducted at Stennis Space Center and the 5% Ares I Scale Model Acoustic Test conducted at Marshall Space Flight Center.

  2. Energy Cascade Analysis: from Subscale Eddies to Mean Flow

    Science.gov (United States)

    Cheikh, Mohamad Ibrahim; Wonnell, Louis; Chen, James

    2017-11-01

    Understanding the energy transfer between eddies and mean flow can provide insights into the energy cascade process. Much work has been done to investigate the energy cascade at the level of the smallest eddies using different numerical techniques derived from the Navier-Stokes equations. These methodologies, however, prove to be computationally inefficient when producing energy spectra for a wide range of length scales. In this regard, Morphing Continuum Theory (MCT) resolves the length-scales issues by assuming the fluid continuum to be composed of inner structures that play the role of subscale eddies. The current study show- cases the capabilities of MCT in capturing the dynamics of energy cascade at the level of subscale eddies, through a supersonic turbulent flow of Mach 2.93 over an 8× compression ramp. Analysis of the results using statistical averaging procedure shows the existence of a statistical coupling of the internal and translational kinetic energy fluctuations with the corresponding rotational kinetic energy of the subscale eddies, indicating a multiscale transfer of energy. The results show that MCT gives a new characterization of the energy cascade within compressible turbulence without the use of excessive computational resources. This material is based upon work supported by the Air Force Office of Scientific Research under Award Number FA9550-17-1-0154.

  3. Improving QST Reliability – More Raters, Tests or Occasions? A Multivariate Generalizability Study

    DEFF Research Database (Denmark)

    O'Neill, Søren; O'Neill, Lotte

    2015-01-01

    The reliability of quantitative sensory testing (QST) is affected by the error attributable to both test occasion and rater (examiner) as well as interactions between them. Most reliability studies only account for one source of error. The present study employed a fully-crossed, multivariate...... (relative contribution [19%,78%]). Error attributable to the interaction between study participant and occasion was also influential. Dependability coefficients indicated, that a substantial increase in reliability and feasibility could be achieved by employing a composite QST battery compared to single QST...

  4. A Reliability Generalization Meta-Analysis of Coefficient Alpha for the Maslach Burnout Inventory

    Science.gov (United States)

    Wheeler, Denna L.; Vassar, Matt; Worley, Jody A.; Barnes, Laura L. B.

    2011-01-01

    The purpose of this study was to synthesize internal consistency reliability for the subscale scores on the Maslach Burnout Inventory (MBI). The authors addressed three research questions: (a) What is the mean subscale score reliability for the MBI across studies? (b) What factors are associated with observed variance in MBI subscale score…

  5. Improving the reliability of seasonal climate forecasts through empirical downscaling and multi-model considerations; presentation

    CSIR Research Space (South Africa)

    Landman, WA

    2012-11-01

    Full Text Available embody degrees of uncertainty, often expressed as a probabilistic outcome. Since seasonal prediction is inherently probabilistic in nature they are judged (i.e. verified) probabilistically through attributes including reliability, resolution...

  6. Application of classification principles to improve the reliability of incident classification systems: A test case using HFACS-ADF.

    Science.gov (United States)

    Olsen, Nikki; Williamson, Ann

    2017-09-01

    Accident classification systems are important tools for safety management. Unfortunately, many of the tools available have demonstrated poor reliability of coding, making their validity and usefulness questionable. This paper demonstrates the application of four strategies to improve the reliability of accident and incident classification systems. The strategies include creating a domain-specific system with limitations on system size and careful selection of codes, specifically the reduction of abstract concepts and bias-causing terminology. Using HFACS-ADF as a test case, the system was adapted using the strategies and validated using comprehension and comprehensiveness testing. The new system was then assessed for reliability. The reliability of the system increased by at least 20% at all levels of the classification system following the changes made. The results provide evidence that the application of theoretically and empirically-derived classification principles are effective for improving the reliability of accident and incident classification systems in high hazard industries. Copyright © 2017 Elsevier Ltd. All rights reserved.

  7. Increasing reliability of APACHE II scores in a medical-surgical intensive care unit: a quality improvement study.

    Science.gov (United States)

    Donahoe, Laura; McDonald, Ellen; Kho, Michelle E; Maclennan, Margaret; Stratford, Paul W; Cook, Deborah J

    2009-01-01

    Given their clinical, research, and administrative purposes, scores on the Acute Physiology and Chronic Health Evaluation (APACHE) II should be reliable, whether calculated by health care personnel or a clinical information system. To determine reliability of APACHE II scores calculated by a clinical information system and by health care personnel before and after a multifaceted quality improvement intervention. APACHE II scores of 37 consecutive patients admitted to a closed, 15-bed, university-affiliated intensive care unit were collected by a research coordinator, a database clerk, and a clinical information system. After a quality improvement intervention focused on health care personnel and the clinical information system, the same methods were used to collect data on 32 consecutive patients. The research coordinator and the clerk did not know each other's scores or the information system's score. The data analyst did not know the source of the scores until analysis was complete. APACHE II scores obtained by the clerk and the research coordinator were highly reliable (intraclass correlation coefficient, 0.88 before vs 0.80 after intervention; P = .25). No significant changes were detected after the intervention; however, compared with scores of the research coordinator, the overall reliability of APACHE II scores calculated by the clinical information system improved (intraclass correlation coefficient, 0.24 before intervention vs 0.91 after intervention, P APACHE II scores for clinical, research, and administrative purposes.

  8. Indirect thermal control for improved reliability of Modular Multilevel Converter by utilizing circulating current

    DEFF Research Database (Denmark)

    Dowlatabadi, Mohammadkazem Bakhshizadeh; Ma, Ke; Loh, Poh Chiang

    2015-01-01

    Modular Multilevel Converter (MMC) has recently become a popular multilevel topology for high-power applications, where the reliability performance is a crucial design consideration. In this paper the impacts of the circulating current in the MMC to the loss and thermal loading of power...... semiconductor devices are comprehensively investigated. Also a novel control strategy by utilizing the circulating current is proposed to enhance the reliability performance of MMC in order to limit the amplitude of thermal cycles. It is concluded that the circulating current may change the losses and thermal...

  9. Scoring haemophilic arthropathy on X-rays: improving inter- and intra-observer reliability and agreement using a consensus atlas

    Energy Technology Data Exchange (ETDEWEB)

    Foppen, Wouter; Schaaf, Irene C. van der; Beek, Frederik J.A. [University Medical Center Utrecht, Department of Radiology (Netherlands); Verkooijen, Helena M. [University Medical Center Utrecht, Department of Radiology (Netherlands); University Medical Center Utrecht, Julius Center for Health Sciences and Primary Care, Utrecht (Netherlands); Fischer, Kathelijn [University Medical Center Utrecht, Julius Center for Health Sciences and Primary Care, Utrecht (Netherlands); University Medical Center Utrecht, Van Creveldkliniek, Department of Hematology, Utrecht (Netherlands)

    2016-06-15

    The radiological Pettersson score (PS) is widely applied for classification of arthropathy to evaluate costly haemophilia treatment. This study aims to assess and improve inter- and intra-observer reliability and agreement of the PS. Two series of X-rays (bilateral elbows, knees, and ankles) of 10 haemophilia patients (120 joints) with haemophilic arthropathy were scored by three observers according to the PS (maximum score 13/joint). Subsequently, (dis-)agreement in scoring was discussed until consensus. Example images were collected in an atlas. Thereafter, second series of 120 joints were scored using the atlas. One observer rescored the second series after three months. Reliability was assessed by intraclass correlation coefficients (ICC), agreement by limits of agreement (LoA). Median Pettersson score at joint level (PS{sub joint}) of affected joints was 6 (interquartile range 3-9). Using the consensus atlas, inter-observer reliability of the PS{sub joint} improved significantly from 0.94 (95 % confidence interval (CI) 0.91-0.96) to 0.97 (CI 0.96-0.98). LoA improved from ±1.7 to ±1.1 for the PS{sub joint}. Therefore, true differences in arthropathy were differences in the PS{sub joint} of >2 points. Intra-observer reliability of the PS{sub joint} was 0.98 (CI 0.97-0.98), intra-observer LoA were ±0.9 points. Reliability and agreement of the PS improved by using a consensus atlas. (orig.)

  10. Description and Operation of the A3 Subscale Facility

    Science.gov (United States)

    Saunders, G. P.; Varner, D. G.; Grover, J. B.

    2010-01-01

    The purpose of this paper is to give an overview of the general design and operation of the A3 Subscale test facility. The goal is to provide the reader with a general understanding of what the major facility systems are, where they are located, and how they are used to meet the objectives supporting the design of the A3 altitude rocket test facility. This paper also provides the reader with the background information prior to reading the subsequent papers detailing the design and test results of the various systems described herein.

  11. PERFORMANCE, RELIABILITY, AND IMPROVEMENT OF A TISSUE-SPECIFIC METABOLIC SIMULATOR

    Science.gov (United States)

    A methodology is described that has been used to build and enhance a simulator for rat liver metabolism providing reliable predictions within a large chemical domain. The tissue metabolism simulator (TIMES) utilizes a heuristic algorithm to generate plausible metabolic maps using...

  12. Improved Reliability of Orbital Rendezvous Operations by Using Small Satellites for Reconnaissance

    Science.gov (United States)

    Rughani, Rahul

    This research explores the use of cubesats as an alternative to fixed radar platforms when performing rendezvous operations between spacecraft in orbit. In order to be a viable alternative, this system needs to be at least as reliable as current systems in use, less costly, and most importantly it must be safe. The main goal of this research is to investigate the application of this system architecture in Low Earth Orbit (LEO), however it can also be applied in Geostationary Orbit (GEO) as will be shown later on. To do this, reliability, safety, and orbit simulations were created in Matlab and run for various formations of cubesats. The system reliability was modeled using an aggregation of the reliabilities of the individual components, with the reliability decreasing exponentially over time. The orbital dynamics of the rendezvous motion was modeled using the Clohessy-Wiltshire linearized approximations for relative motion. Safety analysis was performed by analyzing the orbital characteristics of the system given small perturbations at critical points in the mission, observing how this changes the dynamics of the system and whether or not these changes could make the system unsafe, or dangerous to other spacecraft. The results of these simulations yielded interesting results, demonstrating that such a system architecture can in fact be cheaper, more reliable, and safer than current systems in use, so long as a minimum number of cubesats are employed. Not only can the system be more reliable than current systems, it also has the ability to gather much more accurate data due to the multiple vantage points available. This research also investigates a potential design for the cubesat to be used for this mission. It has been designed in order to acquire targets and function even in the case when the target spacecraft is damaged and unresponsive, or sending bad data to operators on the ground. This ability to rendezvous with a non-cooperative spacecraft is not possible

  13. Improving Phrap-based assembly of the rat using "reliable" overlaps.

    Directory of Open Access Journals (Sweden)

    Michael Roberts

    2008-03-01

    Full Text Available The assembly methods used for whole-genome shotgun (WGS data have a major impact on the quality of resulting draft genomes. We present a novel algorithm to generate a set of "reliable" overlaps based on identifying repeat k-mers. To demonstrate the benefits of using reliable overlaps, we have created a version of the Phrap assembly program that uses only overlaps from a specific list. We call this version PhrapUMD. Integrating PhrapUMD and our "reliable-overlap" algorithm with the Baylor College of Medicine assembler, Atlas, we assemble the BACs from the Rattus norvegicus genome project. Starting with the same data as the Nov. 2002 Atlas assembly, we compare our results and the Atlas assembly to the 4.3 Mb of rat sequence in the 21 BACs that have been finished. Our version of the draft assembly of the 21 BACs increases the coverage of finished sequence from 93.4% to 96.3%, while simultaneously reducing the base error rate from 4.5 to 1.1 errors per 10,000 bases. There are a number of ways of assessing the relative merits of assemblies when the finished sequence is available. If one views the overall quality of an assembly as proportional to the inverse of the product of the error rate and sequence missed, then the assembly presented here is seven times better. The UMD Overlapper with options for reliable overlaps is available from the authors at http://www.genome.umd.edu. We also provide the changes to the Phrap source code enabling it to use only the reliable overlaps.

  14. The use of Spielberger's State-Trait Personality Inventory (trait anxiety subscale) with naval subaquatic specialists.

    Science.gov (United States)

    Van Wijk, Charles H

    2014-12-01

    Panic behavior poses a particular threat to the health and safety of subaquatic occupational specialists. Trait anxiety has previously been identified as a marker of panic behavior under water, and Spielberger's State-Trait Personality Inventory (trait anxiety subscale) has been previously used to measure trait anxiety among subaquatic specialists. Using archived data, the trait anxiety scores of subaquatic specialists were analyzed to meet 3 objectives: 1stly - to develop a trait anxiety profile of subaquatic specialists; 2ndly - to investigate the predictive value of trait anxiety measures upon entering an occupational field; and 3rdly - to establish the reliability of these scores over time. Archival trait-anxiety data from 322 subjects were analyzed statistically. Analysis of the available scores revealed a highly homogenous as well as a very low trait anxiety profile for the investigated occupational group. Additionally, low trait anxiety was somewhat associated with success during specialist training: fewer candidates with high trait anxiety scores completed their qualification. Moreover, measurement of trait anxiety was stable over time, which suggests that when scores for this occupational group are screened, deviations from previous scores could signify a potential need for referral to an intervention from health professionals. Using the trait anxiety subscale as part of occupational health surveillance of subaquatic specialists could support prevention of accidents by identifying high-risk candidates during their annual health assessments, and referral for timeous intervention.

  15. Improvement of Reliability of Compressors for Domestics Refrigerators using HFC134a

    Science.gov (United States)

    Iizuka, Tadashi; Hata, Hiroaki

    In concerning with the trend for the phase out of CFC's,we have developed the technology for the rolling piston type rotary compressors for refrigerators using HFC134a. It is known that the reliability of compressors is less when using HFC134a for conventional compressors without any modifications than that when using CFC12. We have estimated some kinds of refrigerating oil,materials for motors,mechanical parts, and their compatibility for HFC134a. The life test using the compressors with the new oil,motor materials,and modified mechanical parts was carried out and it has been found that the reliability equivalent to that of CFC12 system can be maintained. However,this test only could estimate there liability of compressors under a certain limited condition. So we are now continuing extend examination to adapt the above-mentioned technology to various actual use.

  16. PROPOSALS TO IMPROVE THE RELIABILITY MODELING IN THE CASES OF TRUNCATED TESTS

    Directory of Open Access Journals (Sweden)

    Jan-Cristian GRIGORE

    2012-05-01

    Full Text Available For modeling the reliability, there are used specifically designed computing programs, two situations being possible: complete tests and incomplete tests. However, it is found that in the cases of incomplete tests it is not made distinguish between the censored type testing (which ends when a preset number of products of considered batch failed and the truncated type testing (which ends at a predetermined time moment. In the case of the incomplete type testing, there is not taken into consideration the time interval between the moment of the last failure and the moment of the end of the experiment (the case of truncated type testing. Therefore, based on the realized study, there is proposed a computing algorithm for modeling the reliability through the usual mathematical laws (Weibull, exponential, normal when trying truncated type. The results obtained confirm the usefulness of theoretical and practical computational algorithms proposed

  17. 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...

  18. Needs assessment for nondestructive testing and materials characterization for improved reliability in structural ceramics for heat engines

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, D.R.; McClung, R.W.; Janney, M.A.; Hanusiak, W.M.

    1987-08-01

    A needs assessment was performed for nondestructive testing and materials characterization to achieve improved reliability in ceramic materials for heat engine applications. Raw materials, green state bodies, and sintered ceramics were considered. The overall approach taken to improve reliability of structural ceramics requires key inspections throughout the fabrication flowsheet, including raw materials, greed state, and dense parts. The applications of nondestructive inspection and characterization techniques to ceramic powders and other raw materials, green ceramics, and sintered ceramics are discussed. The current state of inspection technology is reviewed for all identified attributes and stages of a generalized flowsheet for advanced structural ceramics, and research and development requirements are identified and listed in priority order. 164 refs., 3 figs.

  19. Does gymnastics practice improve vertical jump reliability from the age of 8 to 10 years?

    Science.gov (United States)

    Marina, Michel; Torrado, Priscila

    2013-01-01

    The objective of this study was to confirm whether gymnastics practice from a young age can induce greater vertical jump reliability. Fifty young female gymnasts (8.84 ± 0.62 years) and 42 females in the control group (8.58 ± 0.92 years) performed the following jump tests on a contact mat: squat jump, countermovement jump, countermovement jump with arm swing and drop jump from heights of 40 and 60 cm. The two testing sessions had three trials each and were separated by one week. A 2 (groups) × 2 (sessions) × 3 (trials) repeated measures analysis of variance (ANOVA) and a test-retest correlation analysis were used to study the reliability. There was no systematic source of error in either group for non-plyometric jumps such as squat jump, countermovement jump, and countermovement jump with arm swing. A significant group per trial interaction revealed a learning effect in gymnasts' drop jumps from 40 cm height. Additionally, the test-retest correlation analysis and the higher minimum detectable error suggest that the quick drop jump technique was not fully consolidated in either group. At an introductory level of gymnastics and between the ages of 8-10 years, the condition of being a gymnast did not lead to conclusively higher reliability, aside from better overall vertical jump performance.

  20. How to improve centrifugal pumps reliability; Como aumentar a confiabilidade de bombas centrifugas

    Energy Technology Data Exchange (ETDEWEB)

    Pedreira, Java Atayde [PETROBRAS S.A., Rio de Janeiro, RJ (Brazil)

    2004-07-01

    The competitive market where the petroleum and petrochemicals industries are inserted has been taking to significant reductions of its profit margins, leading them to pursue costs reduction and change its way of working, in order to turn them more competitive. The reliability of the plant has a direct impact in the operational costs and it is extremely dependent of the performance of the rotating equipment, predominantly centrifugal pumps. Investments for optimize the reliability of the plants and to reduce the maintenance needs have become imperative for the reduction of the operational and maintenance costs. And why do the pumps fail so much? This is a question that all the pump users make themselves, dealing with an apparently so simple equipment. The pump maintenance costs is about 30 % of rotating equipment total cost.Vibration, mechanical seal failures and efficiency loss are the greatest responsible causes of such high maintenance costs. Many factors should be considered in the analysis of the causes of such low performance. Errors of project, application, installation, maintenance and operation of the pumps are the greatest responsible factors for its low performance. This article makes a detailed analysis of the impact of these factors in the performance of these equipment, discussing the best practices that should be adopted and maintained, in order to assure an optimum reliability. (author)

  1. Improvement of reliability of molecular DNA computing: solution of inverse problem of Raman spectroscopy using artificial neural networks

    Science.gov (United States)

    Dolenko, T. A.; Burikov, S. A.; Vervald, E. N.; Efitorov, A. O.; Laptinskiy, K. A.; Sarmanova, O. E.; Dolenko, S. A.

    2017-02-01

    Elaboration of methods for the control of biochemical reactions with deoxyribonucleic acid (DNA) strands is necessary for the solution of one of the basic problems in the creation of biocomputers—improvement in the reliability of molecular DNA computing. In this paper, the results of the solution of the four-parameter inverse problem of laser Raman spectroscopy—the determination of the type and concentration of each of the DNA nitrogenous bases in multi-component solutions—are presented.

  2. Body surface assessment with 3D laser-based anthropometry: reliability, validation, and improvement of empirical surface formulae.

    Science.gov (United States)

    Kuehnapfel, Andreas; Ahnert, Peter; Loeffler, Markus; Scholz, Markus

    2017-02-01

    Body surface area is a physiological quantity relevant for many medical applications. In clinical practice, it is determined by empirical formulae. 3D laser-based anthropometry provides an easy and effective way to measure body surface area but is not ubiquitously available. We used data from laser-based anthropometry from a population-based study to assess validity of published and commonly used empirical formulae. We performed a large population-based study on adults collecting classical anthropometric measurements and 3D body surface assessments (N = 1435). We determined reliability of the 3D body surface assessment and validity of 18 different empirical formulae proposed in the literature. The performance of these formulae is studied in subsets of sex and BMI. Finally, improvements of parameter settings of formulae and adjustments for sex and BMI were considered. 3D body surface measurements show excellent intra- and inter-rater reliability of 0.998 (overall concordance correlation coefficient, OCCC was used as measure of agreement). Empirical formulae of Fujimoto and Watanabe, Shuter and Aslani and Sendroy and Cecchini performed best with excellent concordance with OCCC > 0.949 even in subgroups of sex and BMI. Re-parametrization of formulae and adjustment for sex and BMI slightly improved results. In adults, 3D laser-based body surface assessment is a reliable alternative to estimation by empirical formulae. However, there are empirical formulae showing excellent results even in subgroups of sex and BMI with only little room for improvement.

  3. Using data from Multidimensional Pain Inventory subscales to assess functioning in pain rehabilitation

    DEFF Research Database (Denmark)

    Harlacher, Uwe; Persson, Ann L; Rivano-Fischer, Marcelo

    2011-01-01

    The aim of this study was to examine whether Multidimensional Pain Inventory (MPI) subscale score changes can be used for monitoring interdisciplinary cognitive behavioural pain rehabilitation programmes, using the Psychological General Well-Being (PGWB) index as an independent variable...... of rehabilitation outcome. Data from 434 consecutively referred patients disabled by chronic pain were analysed. The intervention was a 4-week interdisciplinary pain rehabilitation group programme (5 h/day), based on biopsychosocial and cognitive behavioural principles. Mean PGWB total scores improved after...... rehabilitation (P...

  4. Hydrogen Compressor Reliability Investigation and Improvement. Cooperative Research and Development Final Report, CRADA Number CRD-13-514

    Energy Technology Data Exchange (ETDEWEB)

    Terlip, Danny [National Renewable Energy Lab. (NREL), Golden, CO (United States)

    2016-03-28

    Diaphragm compressors have become the primary source of on-site hydrogen compression for hydrogen fueling stations around the world. NREL and PDC have undertaken two studies aimed at improving hydrogen compressor operation and reducing the cost contribution to dispensed fuel. The first study identified the failure mechanisms associated with mechanical compression to reduce the maintenance and down-time. The second study will investigate novel station configurations to maximize hydrogen usage and compressor lifetime. This partnership will allow for the simulation of operations in the field and a thorough analysis of the component failure to improve the reliability of diaphragm compression.

  5. Beyond redundancy how geographic redundancy can improve service availability and reliability of computer-based systems

    CERN Document Server

    Bauer, Eric; Eustace, Dan

    2012-01-01

    "While geographic redundancy can obviously be a huge benefit for disaster recovery, it is far less obvious what benefit is feasible and likely for more typical non-catastrophic hardware, software, and human failures. Georedundancy and Service Availability provides both a theoretical and practical treatment of the feasible and likely benefits of geographic redundancy for both service availability and service reliability. The text provides network/system planners, IS/IT operations folks, system architects, system engineers, developers, testers, and other industry practitioners with a general discussion about the capital expense/operating expense tradeoff that frames system redundancy and georedundancy"--

  6. Reliability and Maintainability Model (RAM): User and Maintenance Manual. Part 2; Improved Supportability Analysis

    Science.gov (United States)

    Ebeling, Charles E.

    1996-01-01

    This report documents the procedures for utilizing and maintaining the Reliability & Maintainability Model (RAM) developed by the University of Dayton for the National Aeronautics and Space Administration (NASA) Langley Research Center (LaRC). The purpose of the grant is to provide support to NASA in establishing operational and support parameters and costs of proposed space systems. As part of this research objective, the model described here was developed. This Manual updates and supersedes the 1995 RAM User and Maintenance Manual. Changes and enhancements from the 1995 version of the model are primarily a result of the addition of more recent aircraft and shuttle R&M data.

  7. A dissociation between engagement and learning: Enthusiastic instructions fail to reliably improve performance on a memory task.

    Science.gov (United States)

    Motz, Benjamin A; de Leeuw, Joshua R; Carvalho, Paulo F; Liang, Kaley L; Goldstone, Robert L

    2017-01-01

    Despite widespread assertions that enthusiasm is an important quality of effective teaching, empirical research on the effect of enthusiasm on learning and memory is mixed and largely inconclusive. To help resolve these inconsistencies, we conducted a carefully-controlled laboratory experiment, investigating whether enthusiastic instructions for a memory task would improve recall accuracy. Scripted videos, either enthusiastic or neutral, were used to manipulate the delivery of task instructions. We also manipulated the sequence of learning items, replicating the spacing effect, a known cognitive technique for memory improvement. Although spaced study reliably improved test performance, we found no reliable effect of enthusiasm on memory performance across two experiments. We did, however, find that enthusiastic instructions caused participants to respond to more item prompts, leaving fewer test questions blank, an outcome typically associated with increased task motivation. We find no support for the popular claim that enthusiastic instruction will improve learning, although it may still improve engagement. This dissociation between motivation and learning is discussed, as well as its implications for education and future research on student learning.

  8. Improving reliability of state estimation programming and computing suite based on analyzing a fault tree

    Directory of Open Access Journals (Sweden)

    Kolosok Irina

    2017-01-01

    Full Text Available Reliable information on the current state parameters obtained as a result of processing the measurements from systems of the SCADA and WAMS data acquisition and processing through methods of state estimation (SE is a condition that enables to successfully manage an energy power system (EPS. SCADA and WAMS systems themselves, as any technical systems, are subject to failures and faults that lead to distortion and loss of information. The SE procedure enables to find erroneous measurements, therefore, it is a barrier for the distorted information to penetrate into control problems. At the same time, the programming and computing suite (PCS implementing the SE functions may itself provide a wrong decision due to imperfection of the software algorithms and errors. In this study, we propose to use a fault tree to analyze consequences of failures and faults in SCADA and WAMS and in the very SE procedure. Based on the analysis of the obtained measurement information and on the SE results, we determine the state estimation PCS fault tolerance level featuring its reliability.

  9. Using multi-model averaging to improve the reliability of catchment scale nitrogen predictions

    Directory of Open Access Journals (Sweden)

    J.-F. Exbrayat

    2013-01-01

    Full Text Available Hydro-biogeochemical models are used to foresee the impact of mitigation measures on water quality. Usually, scenario-based studies rely on single model applications. This is done in spite of the widely acknowledged advantage of ensemble approaches to cope with structural model uncertainty issues. As an attempt to demonstrate the reliability of such multi-model efforts in the hydro-biogeochemical context, this methodological contribution proposes an adaptation of the reliability ensemble averaging (REA philosophy to nitrogen losses predictions. A total of 4 models are used to predict the total nitrogen (TN losses from the well-monitored Ellen Brook catchment in Western Australia. Simulations include re-predictions of current conditions and a set of straightforward management changes targeting fertilisation scenarios. Results show that, in spite of good calibration metrics, one of the models provides a very different response to management changes. This behaviour leads the simple average of the ensemble members to also predict reductions in TN export that are not in agreement with the other models. However, considering the convergence of model predictions in the more sophisticated REA approach assigns more weight to previously less well-calibrated models that are more in agreement with each other. This method also avoids having to disqualify any of the ensemble members.

  10. Inter- and Intrarater Reliabilities of the Test of Gross Motor Development-Third Edition Among Experienced TGMD-2 Raters.

    Science.gov (United States)

    Maeng, Hyokju; Webster, E Kipling; Pitchford, E Andrew; Ulrich, Dale A

    2017-10-01

    The purpose of this study was to examine the inter- and intrarater reliabilities of the Test of Gross Motor Development-third edition (TGMD-3). The TGMD-3 was administered to 10 typically developing children. Five raters with experience using the Test of Gross Motor Development-second edition (TGMD-2) scored the digitally recorded performances and then rescored the same performances after a period of 2 weeks. Intraclass correlation (ICC) was used to examine both inter- and intrarater reliabilities of scores. Interrater reliability for the total score, locomotor subscale, and ball skills subscale (ICC: 0.92-0.96) were all excellent, while individual skills (ICC: 0.51-0.93) had fair-to-excellent reliability. Intrarater reliability across all raters was also excellent (ICC: 0.77-0.98) but varied widely for individual raters (ICC: 0.28-1.00) including multiple examples of poor reliability. While raters experienced with the TGMD-2 can produce consistent scores for TGMD-3 total scale and subscales, additional training is needed to improve skill-specific reliability.

  11. Improving the reliability of the jpHMM recombination prediction in HIV

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Ming [Los Alamos National Laboratory; Letiner, Thomas K [Los Alamos National Laboratory; Korber, Bette T [Los Alamos National Laboratory

    2008-01-01

    Accurate classification of HIV and the identification of recombinants, including precise breakpoint definitions, is of crucial importance for epidemiological monitoring and the design of potential drugs. Recently we developed jpHMM, a new method to detect recombinations in HIV-l genomes. jpHMM predicts phylogenetic recombination breakpoints in a query sequence and assigns to each segment of the sequence one of the major HIV-l subtypes. For the user the reliability of the predicted breakpoint positions and parental subtypes is most important. For this reason we extended the output of jpHMM to include the information on regions where the model is 'uncertain' about the parental subtype and an interval estimate of the breakpoint. This information is determined using the posterior probabilities of the subtypes at each query sequence position.

  12. Improving Wind Turbine Drivetrain Reliability Using a Combined Experimental, Computational, and Analytical Approach

    Energy Technology Data Exchange (ETDEWEB)

    Guo, Y.; van Dam, J.; Bergua, R.; Jove, J.; Campbell, J.

    2015-03-01

    Nontorque loads induced by the wind turbine rotor overhang weight and aerodynamic forces can greatly affect drivetrain loads and responses. If not addressed properly, these loads can result in a decrease in gearbox component life. This work uses analytical modeling, computational modeling, and experimental data to evaluate a unique drivetrain design that minimizes the effects of nontorque loads on gearbox reliability: the Pure Torque(R) drivetrain developed by Alstom. The drivetrain has a hub-support configuration that transmits nontorque loads directly into the tower rather than through the gearbox as in other design approaches. An analytical model of Alstom's Pure Torque drivetrain provides insight into the relationships among turbine component weights, aerodynamic forces, and the resulting drivetrain loads. Main shaft bending loads are orders of magnitude lower than the rated torque and are hardly affected by wind conditions and turbine operations.

  13. Improving Reliability of Service Operation Using FMEA Review and New Opportunity for Investigations

    Science.gov (United States)

    Sutrisno, Agung; Gunawan, Indra

    2016-01-01

    Despite its growing contribution to the global economy, investigation on the application status of service FMEA study to support realization of reliable service operation is very limited in literature. Motivated by such situation, the paper presented an initial survey on the status and research gaps in developing and applying FMEA in service sectors. Systematic preliminary survey using specific criteria are undertaken. Our study indicated that development and application of service FMEA are partially addressing the characteristics of service operations and it is still applied into the good deed and profit oriented operations. Opportunities for further investigation pertaining to advancement of its decision supporting tool for service risk appraisal, its modification to cope with sustainability related requirements and application of service FMEA in not for profit oriented operations are presented as new avenues for further investigation

  14. Using Model Replication to Improve the Reliability of Agent-Based Models

    Science.gov (United States)

    Zhong, Wei; Kim, Yushim

    The basic presupposition of model replication activities for a computational model such as an agent-based model (ABM) is that, as a robust and reliable tool, it must be replicable in other computing settings. This assumption has recently gained attention in the community of artificial society and simulation due to the challenges of model verification and validation. Illustrating the replication of an ABM representing fraudulent behavior in a public service delivery system originally developed in the Java-based MASON toolkit for NetLogo by a different author, this paper exemplifies how model replication exercises provide unique opportunities for model verification and validation process. At the same time, it helps accumulate best practices and patterns of model replication and contributes to the agenda of developing a standard methodological protocol for agent-based social simulation.

  15. Updating temperature monitoring on reciprocating compressor connecting rods to improve reliability

    Directory of Open Access Journals (Sweden)

    Jim Townsend

    2016-03-01

    The compressors are used to move CO2 and boost the gas to the required field pressure, usually around 2,200 psig. Reciprocating compressors are flexible and able to handle wide capacity and condition swings, offer an efficient method of compressing almost any gas composition in a wide range of pressures and have numerous applications and wide power ratings. This makes them a vital component in various industrial facilities. Condition monitoring of critical rotating machinery is widely accepted by operators of centrifugal compressors. However, condition monitoring of reciprocating machinery such as compressors and internal combustion engines has not received the same degree of acceptance. This paper examines the reliability impact as a result of upgrading the temperature monitoring devices on the connecting rods of electric driven reciprocating compressors. A cost analysis is also presented to demonstrate that the upgrade in hardware and software will eventually yield a saving in the operating cost.

  16. [Conflict of interest disclosure as a tool to improve the reliability of research].

    Science.gov (United States)

    Soto Subiabre, Mauricio

    2016-08-01

    Conflicts of interest are situations in which professional judgment concerning a primary interest, tends to be influenced by a secondary interest. These conflicts could compromise the reliability of biomedical research and result in the dissemination of biased results. Therefore, it is essential to protect the integrity of them, because this information could be used in the development of health policy, medical education and clinical decision making. Conflicts of interest disclosure, is a bioethical tool that contributes to transparent these conflicts, but it is used inappropriately and insufficiently. To be useful, it must be based on clear principles, it should help to perform a critical analysis and should be considered in the design of every research project. This review is an analysis of the conflicts of interest disclosure, its scope and limitations and should contribute to develop a greater awareness of its importance.

  17. Improvement of mechanical reliability by patterned silver/Indium-Tin-Oxide structure for flexible electronic devices

    Energy Technology Data Exchange (ETDEWEB)

    Baek, Kyunghyun; Jang, Kyungsoo; Lee, Youn-Jung; Ryu, Kyungyul; Choi, Woojin [School of Electronic Electrical Engineering, College of Information and Communication Engineering, Sungkyunkwan University, Suwon 440-746 (Korea, Republic of); Kim, Doyoung [School of Electricity and Electronics, Ulsan College, Ulsan 680-749 (Korea, Republic of); Yi, Junsin, E-mail: yi@yurim.skku.ac.kr [School of Electronic Electrical Engineering, College of Information and Communication Engineering, Sungkyunkwan University, Suwon 440-746 (Korea, Republic of)

    2013-03-01

    We report the effect of silver (Ag)-buffer layer Indium-Tin-Oxide (ITO) film on a polyethylene terephthalate substrate on the electrical, optical and reliable properties for transparent–flexible displays. The electrical and optical characteristics of an ITO-only film and an Ag-layer-inserted ITO film are measured and compared to assess the applicability of the triple layered structure in flexible displays. The sheet resistance, the resistivity and the light transmittance of the ITO-only film were 400 Ω/sq, 1.33 × 10{sup −3} Ω-cm and 99.2%, while those of the ITO film inserted with a 10 nm thick Ag layer were 165 Ω/sq, 4.78 × 10{sup −4} Ω-cm and about 97%, respectively. To evaluate the mechanical reliability of the different ITO films, bending tests were carried out. After the dynamic bending test of 900 cycles, the sheet resistance of the ITO film inserted with the Ag layer changed from 154 Ω/sq to 475 Ω/sq, about a 3-time increase but that of the ITO-only film changed from 400 Ω/sq to 61,986 Ω/sq, about 150-time increase. When the radius is changed from 25 mm to 20 mm in the static bending test, the sheet resistance of the ITO-only film changed from 400 to 678.3 linearly whereas that of the Ag-layer inserted ITO film changed a little from 154.4 to 154.9. These results show that Ag-layer inserted ITO film had better mechanical characteristics than the ITO-only film. - Highlights: ► Transparent flexible electrode fabricated on glass substrate. ► Electrode fabricated using vertically-patterned design on glass substrate. ► Optimization of the vertical patterns ► Application of the vertically-patterned electrode in transparent–flexible electronics.

  18. Improving preimplantation genetic diagnosis (PGD) reliability by selection of sperm donor with the most informative haplotype.

    Science.gov (United States)

    Malcov, Mira; Gold, Veronica; Peleg, Sagit; Frumkin, Tsvia; Azem, Foad; Amit, Ami; Ben-Yosef, Dalit; Yaron, Yuval; Reches, Adi; Barda, Shimi; Kleiman, Sandra E; Yogev, Leah; Hauser, Ron

    2017-04-26

    The study is aimed to describe a novel strategy that increases the accuracy and reliability of PGD in patients using sperm donation by pre-selecting the donor whose haplotype does not overlap the carrier's one. A panel of 4-9 informative polymorphic markers, flanking the mutation in carriers of autosomal dominant/X-linked disorders, was tested in DNA of sperm donors before PGD. Whenever the lengths of donors' repeats overlapped those of the women, additional donors' DNA samples were analyzed. The donor that demonstrated the minimal overlapping with the patient was selected for IVF. In 8 out of 17 carriers the markers of the initially chosen donors overlapped the patients' alleles and 2-8 additional sperm donors for each patient were haplotyped. The selection of additional sperm donors increased the number of informative markers and reduced misdiagnosis risk from 6.00% ± 7.48 to 0.48% ±0.68. The PGD results were confirmed and no misdiagnosis was detected. Our study demonstrates that pre-selecting a sperm donor whose haplotype has minimal overlapping with the female's haplotype, is critical for reducing the misdiagnosis risk and ensuring a reliable PGD. This strategy may contribute to prevent the transmission of affected IVF-PGD embryos using a simple and economical procedure. All procedures performed in studies involving human participants were in accordance with the ethical standards of the institutional and/or national research committee and with the 1964 Helsinki declaration and its later amendments or comparable ethical standards. DNA testing of donors was approved by the institutional Helsinki committee (registration number 319-08TLV, 2008). The present study was approved by the institutional Helsinki committee (registration number 0385-13TLV, 2013).

  19. Toward Improved Reliability of Seasonal Hydrologic Forecast: Accounting for Initial Condition and State-Parameter Uncertainties

    Science.gov (United States)

    DeChant, C. M.; Moradkhani, H.

    2012-12-01

    Providing reliable estimates of seasonal water supply is a primary goal in operational hydro-meteorological prediction. In order to achieve this goal, it is accepted that hydrologists must accurately estimate forecast initial conditions (land surface states prior to forecast) and the future climate conditions, and quantify the uncertainty in these two forecast stages to provide a full estimation of the uncertainty in a given forecast. Recent work has highlighted the benefits of such a framework through advancing both land surface state estimation techniques and future climate estimation/modeling, within the operational Ensemble Streamflow Prediction (ESP) methodology. Often overlooked in this framework, the uncertainty in land surface state estimates play a key role in providing reliable seasonal forecasts. In order to quantify and reduce this uncertainty, land surface state-parameter estimation, through ensemble data assimilation, is performed with observations of snow and streamflow in a mountainous basin. Through incorporation of both snow and streamflow data for estimation of land surface states and parameters, the quantity of water stored at the land surface can be estimated, and parameter uncertainty can be estimated for seasonal simulations. With the inclusion of parameter uncertainty in the hydrologic forecasting framework, more robust quantification of hydrologic uncertainty is possible, leading to more useful forecasts for end users. This study seeks to examine the role of combined state-parameter estimation for characterization of initial conditions with the potential to be formally adopted in operational ESP framework, and validates results with probabilistic verification of both ESP and ESP with state-parameter estimation.

  20. Improving reliability of non-volatile memory technologies through circuit level techniques and error control coding

    Science.gov (United States)

    Yang, Chengen; Emre, Yunus; Cao, Yu; Chakrabarti, Chaitali

    2012-12-01

    Non-volatile resistive memories, such as phase-change RAM (PRAM) and spin transfer torque RAM (STT-RAM), have emerged as promising candidates because of their fast read access, high storage density, and very low standby power. Unfortunately, in scaled technologies, high storage density comes at a price of lower reliability. In this article, we first study in detail the causes of errors for PRAM and STT-RAM. We see that while for multi-level cell (MLC) PRAM, the errors are due to resistance drift, in STT-RAM they are due to process variations and variations in the device geometry. We develop error models to capture these effects and propose techniques based on tuning of circuit level parameters to mitigate some of these errors. Unfortunately for reliable memory operation, only circuit-level techniques are not sufficient and so we propose error control coding (ECC) techniques that can be used on top of circuit-level techniques. We show that for STT-RAM, a combination of voltage boosting and write pulse width adjustment at the circuit-level followed by a BCH-based ECC scheme can reduce the block failure rate (BFR) to 10-8. For MLC-PRAM, a combination of threshold resistance tuning and BCH-based product code ECC scheme can achieve the same target BFR of 10-8. The product code scheme is flexible; it allows migration to a stronger code to guarantee the same target BFR when the raw bit error rate increases with increase in the number of programming cycles.

  1. Armaflex: More reliability through improved insulation value. Armaflex: Meer zekerheid door verbeterde isolatiewaarde

    Energy Technology Data Exchange (ETDEWEB)

    Hooijkaas, W.F.G. (Afdeling Technologie, Vereniging van Nederlandse Installatiebedrijven, Zoetermeer (Netherlands))

    1992-12-01

    In Muenster, Germany, Armstrong manufactures insulation materials for pipes and ducts. Under the brand AF/Armaflex Armstrong produces insulation materials, based on a 'sealed' cell structure, which protects against humidity. Next to a low heat conductivity ([lambda]<0.036 W/(m.K)) the vapor diffusion resistance [mu]-factor is improved from 3,000 to 5,000. This improvement offers extra security for cooling pipe insulation. 1 fig., 4 ills.

  2. Subscales of the Barratt Impulsiveness Scale differentially relate to the Big Five factors of personality.

    Science.gov (United States)

    Lange, Florian; Wagner, Adina; Müller, Astrid; Eggert, Frank

    2017-06-01

    The place of impulsiveness in multidimensional personality frameworks is still unclear. In particular, no consensus has yet been reached with regard to the relation of impulsiveness to Neuroticism and Extraversion. We aim to contribute to a clearer understanding of these relationships by accounting for the multidimensional structure of impulsiveness. In three independent studies, we related the subscales of the Barratt Impulsiveness Scale (BIS) to the Big Five factors of personality. Study 1 investigated the associations between the BIS subscales and the Big Five factors as measured by the NEO Five-Factor Inventory (NEO-FFI) in a student sample (N = 113). Selective positive correlations emerged between motor impulsiveness and Extraversion and between attentional impulsiveness and Neuroticism. This pattern of results was replicated in Study 2 (N = 132) using a 10-item short version of the Big Five Inventory. In Study 3, we analyzed BIS and NEO-FFI data obtained from a sample of patients with pathological buying (N = 68). In these patients, the relationship between motor impulsiveness and Extraversion was significantly weakened when compared to the non-clinical samples. At the same time, the relationship between attentional impulsiveness and Neuroticism was substantially stronger in the clinical sample. Our studies highlight the utility of the BIS subscales for clarifying the relationship between impulsiveness and the Big Five personality factors. We conclude that impulsiveness might occupy multiple places in multidimensional personality frameworks, which need to be specified to improve the interpretability of impulsiveness scales. © 2017 Scandinavian Psychological Associations and John Wiley & Sons Ltd.

  3. The Mechanical Performance of Subscale Candidate Elastomer Docking Seals

    Science.gov (United States)

    Bastrzyk, Marta B.; Daniels, Christopher C.

    2010-01-01

    The National Aeronautics and Space Administration is developing a Low Impact Docking System (LIDS) for future exploration missions. The mechanism is a new state-of-the-art device for in-space assembly of structures and rendezvous of vehicles. At the interface between two pressurized modules, each with a version of the LIDS attached, a composite elastomer-metal seal assembly prevents the breathable air from escaping into the vacuum of space. Attached to the active LIDS, this seal mates against the passive LIDS during docking operation. The main interface seal assembly must exhibit low leak and outgas values, must be able to withstand various harsh space environments, must remain operational over a range of temperatures from -50 C to 75 C, and perform after numerous docking cycles. This paper presents results from a comprehensive study of the mechanical performance of four candidate subscale seal assembly designs at -50, 23, 50, and 75 C test temperatures. In particular, the force required to fully compress the seal during docking, and that which is required for separation during the undocking operation were measured. The height of subscale main interface seal bulbs, as well as the test temperature, were shown to have a significant effect on the forces the main interface seal of the LIDS may experience during docking and undocking operations. The average force values required to fully compress each of the seal assemblies were shown to increase with test temperature by approximately 50% from -50 to 75 C. Also, the required compression forces were shown to increase as the height of the seal bulb was increased. The seal design with the tallest elastomer seal bulb, which was 31% taller than that with the shortest bulb, required force values approximately 45% higher than those for the shortest bulb, independent of the test temperature. The force required to separate the seal was shown to increase with decreasing temperature after 15 hours of simulated docking. No adhesion

  4. Reliable B cell epitope predictions: impacts of method development and improved benchmarking

    DEFF Research Database (Denmark)

    Kringelum, Jens Vindahl; Lundegaard, Claus; Lund, Ole

    2012-01-01

    incorporating a novel spatial neighborhood definition and half-sphere exposure as surface measure. Compared to other state-of-the-art prediction methods, Discotope-2.0 displayed improved performance both in cross-validation and in independent evaluations. Using DiscoTope-2.0, we assessed the impact...... on performance when using proper benchmark definitions. For 13 proteins in the training data set where sufficient biological information was available to make a proper benchmark redefinition, the average AUC performance was improved from 0.791 to 0.824. Similarly, the average AUC performance on an independent...... evaluation data set improved from 0.712 to 0.727. Our results thus demonstrate that given proper benchmark definitions, B-cell epitope prediction methods achieve highly significant predictive performances suggesting these tools to be a powerful asset in rational epitope discovery. The updated version...

  5. Integrating fuzzy logic and statistics to improve the reliable delimitation of biogeographic regions and transition zones.

    Science.gov (United States)

    Olivero, Jesús; Márquez, Ana L; Real, Raimundo

    2013-01-01

    This study uses the amphibian species of the Mediterranean basin to develop a consistent procedure based on fuzzy sets with which biogeographic regions and biotic transition zones can be objectively detected and reliably mapped. Biogeographical regionalizations are abstractions of the geographical organization of life on Earth that provide frameworks for cataloguing species and ecosystems, for answering basic questions in biogeography, evolutionary biology, and systematics, and for assessing priorities for conservation. On the other hand, limits between regions may form sharply defined boundaries along some parts of their borders, whereas elsewhere they may consist of broad transition zones. The fuzzy set approach provides a heuristic way to analyse the complexity of the biota within an area; significantly different regions are detected whose mutual limits are sometimes fuzzy, sometimes clearly crisp. Most of the regionalizations described in the literature for the Mediterranean biogeographical area present a certain degree of convergence when they are compared within the context of fuzzy interpretation, as many of the differences found between regionalizations are located in transition zones, according to our case study. Compared with other classification procedures based on fuzzy sets, the novelty of our method is that both fuzzy logic and statistics are used together in a synergy in order to avoid arbitrary decisions in the definition of biogeographic regions and transition zones.

  6. Effect of improved contact on reliability of sub-60 nm carbon nanotube vias.

    Science.gov (United States)

    Vyas, Anshul A; Zhou, Changjian; Chai, Yang; Wang, Phillip; Yang, Cary Y

    2016-09-16

    Advances in semiconductor technology due to the aggressive downward scaling of on-chip feature sizes have led to rapid rises in the resistivity and current density of interconnect conductors. As a result, current interconnect materials, Cu and W, are subject to performance and reliability constraints approaching or exceeding their physical limits. Therefore, alternative materials are being actively considered as potential replacements to meet such constraints. The carbon nanotube (CNT) is among the leading replacement candidates for on-chip interconnect vias due to its high aspect-ratio nanostructure and superior current-carrying capacity to Cu and W, as well as other potential candidates. Based on the results for 40 nm and 60 nm top-contact metallized CNT vias, we demonstrate that not only are their current-carrying capacities two orders of magnitude higher than their Cu and W counterparts, they are enhanced by reduced via resistance due to contact engineering facilitated by the first reported contact resistance extraction scheme for a 40 nm linewidth.

  7. A METHOD TO IMPROVE RELIABILITY OF GEARBOX FAULT DETECTION WITH ARTIFICIAL NEURAL NETWORKS

    Directory of Open Access Journals (Sweden)

    P.V. Srihari

    2010-12-01

    Full Text Available Fault diagnosis of gearboxes plays an important role in increasing the availability of machinery in condition monitoring. An effort has been made in this work to develop an artificial neural networks (ANN based fault detection system to increase reliability. Two prominent fault conditions in gears, worn-out and broken teeth, are simulated and five feature parameters are extracted based on vibration signals which are used as input features to the ANN based fault detection system developed in MATLAB, a three layered feed forward network using a back propagation algorithm. This ANN system has been trained with 30 sets of data and tested with 10 sets of data. The learning rate and number of hidden layer neurons are varied individually and the optimal training parameters are found based on the number of epochs. Among the five different learning rates used the 0.15 is deduced to be optimal one and at that learning rate the number of hidden layer neurons of 9 was the optimal one out of the three values considered. Then keeping the training parameters fixed, the number of hidden layers is varied by comparing the performance of the networks and results show the two and three hidden layers have the best detection accuracy.

  8. Reliability improvement of a flexible FD-SOI MOSFET via heat management

    Science.gov (United States)

    Bong, Jae Hoon; Kim, Seung-Yoon; Jeong, Chan Bae; Chang, Ki Soo; Hwang, Wan Sik; Cho, Byung Jin

    2017-06-01

    Ultra-thin single-crystalline Si membrane transistors on a polymer substrate have drawn attention for flexible electronics applications. However, these devices accompany a reliability issue stemming from severe self-heating because of the inherent poor thermal conductivity of the polymer substrate. In the present study, under an operational condition of VG = 3 V and VD = 8 V, the temperature of the Si membrane transistor on the polymer substrate soared to about 64 °C immediately and remained consistently high. The excess heat generated from the active channel significantly degraded the device performance. However, the implementation of a silver heat spreading layer (HSL) between the active channel and the polymer substrate significantly alleviated the self-heating effect as the silver film rapidly spread the generated heat. The efficient heat spreading, monitored via a high resolution infrared thermal microscope, correlated well with the charge transfer characteristics of the device. These results may be helpful to realize high performance flexible devices using a silicon membrane.

  9. Simulation of a GOX-kerosene subscale rocket combustion chamber

    Science.gov (United States)

    Höglauer, Christoph; Kniesner, Björn; Knab, Oliver; Kirchberger, Christoph; Schlieben, Gregor; Kau, Hans-Peter

    2011-12-01

    In view of future film cooling tests at the Institute for Flight Propulsion (LFA) at Technische Universität München, the Astrium in-house spray combustion CFD tool Rocflam-II was validated against first test data gained from this rocket test bench without film cooling. The subscale rocket combustion chamber uses GOX and kerosene as propellants which are injected through a single double swirl element. Especially the modeling of the double swirl element and the measured wall roughness were adapted on the LFA hardware. Additionally, new liquid kerosene fluid properties were implemented and verified in Rocflam-II. Also the influences of soot deposition and hot gas radiation on the wall heat flux were analytically and numerically estimated. In context of reviewing the implemented evaporation model in Rocflam-II, the binary diffusion coefficient and its pressure dependency were analyzed. Finally simulations have been performed for different load points with Rocflam-II showing a good agreement compared to test data.

  10. RF MEMS Switches with SiC Microbridges for Improved Reliability

    Science.gov (United States)

    Scardelletti, Maximilian C.; Zorman, Christian A.; Oldham, Daniel R.

    2008-01-01

    Radio frequency (RF) microelectromechanical (MEMS) switches offer superior performance when compared to the traditional semiconductor devices such as PIN diodes or GaAs transistors. MEMS switches have a return loss (RL) better than -25 dB, negligible insertion loss (IL), isolation better than -30 dB, and near zero power consumption. However, RF MEMS switches have several drawbacks the most serious being long-term reliability. The ability for the switch to operate for millions or even billions of cycles is a major concern and must be addressed. MEMS switches are basically grouped in two categories, capacitive and metal-to-metal contact. The capacitive type switch consists of a movable metal bridge spanning a fixed electrode and separated by a narrow air gap and thin insulating material. The metal-to-metal contact type utilizes the same basic design but without the insulating material. After prolonged operation the metal bridges, in most of these switches, begin to sag and eventually fail to actuate. For the metal-to-metal type, the two metal layers may actually fuse together. Also if the switches are not packaged properly or protected from the environment moisture may build up and cause stiction between the top and bottom electrodes rendering them useless. Many MEMS switch designs have been developed and most illustrate fairly good RF characteristics. Nevertheless very few have demonstrated both great RF performance and ability to perform millions/billions of switching cycles. Of these, nearly all are of metal-to-metal type so as the frequency increases RF performance decreases.

  11. Reliability data to improve high magnetic field coil design for high velocity coilguns.

    Energy Technology Data Exchange (ETDEWEB)

    Kaye, Ronald John; Mann, Gregory Allen

    2003-09-01

    Coilguns have demonstrated their capability to launch projectiles to 1 km/s, and there is interest in their application for long-range precision strike weapons. However, the incorporation of cooling systems for repetitive operation will impact the mechanical design and response of the future coils. To assess the impact of such changes, an evaluation of the ruggedness and reliability of the existing 50 mm bore coil designed in 1993 was made by repeatedly testing at stress levels associated with operation in a coilgun. A two-coil testbed has been built with a static projectile where each coil is energized by its own capacitor bank. Simulation models of the applied forces generated in this testbed have been created with the SLINGSHOT circuit code to obtain loads equivalent to the worst-case anticipated in a 50 mm coilgun that could launch a 236 g projectile to 2 km/s. Bench measurements of the seven remaining coils built in 1993 have been used to evaluate which coils were viable for testing, and only one was found defective. Measurements of the gradient of the effective coil inductance in the presence of the projectile were compared to values from SLINGSHOT, and the agreement is excellent. Repeated testing of the HFC5 coil built in 1993 has demonstrated no failures after 205 shots, which is an order of magnitude greater than any number achieved in previous testing. Although this testing has only been done on two coils, the results are encouraging as it demonstrates there are no fundamental weak links in the design that will cause a very early failure. Several recommendations for future coil designs are suggested based on observations of this study.

  12. The technology - activities of daily living questionnaire: a version with a technology-related subscale.

    Science.gov (United States)

    Muñoz-Neira, Carlos; López, Oscar L; Riveros, Rodrigo; Núñez-Huasaf, Javier; Flores, Patricia; Slachevsky, Andrea

    2012-01-01

    Information and communication technology (ICT) has become an increasingly important part of daily life. The ability to use technology is becoming essential for autonomous functioning in society. Current functional scales for patients with cognitive impairment do not evaluate the use of technology. The objective of this study was to develop and validate a new version of the Activities of Daily Living Questionnaire (ADLQ) that incorporates an ICT subscale. A new technology-based subscale was incorporated into the Spanish version of the ADLQ (SV-ADLQ), entitled the Technology version of the ADLQ (T-ADLQ). The T-ADLQ was administered to 63 caregivers of dementia patients, 21 proxies of mild cognitive impairment patients and 44 proxies of normal elderly subjects (mean age of the sample ± SD: 73.5 ± 8.30 years). We analysed the convergent validity, internal consistency, reliability cut-off point, sensitivity and specificity of the T-ADLQ. The results of the T-ADLQ were compared to the SV-ADLQ. The T-ADLQ showed significant correlations with the Mini-Mental State Examination (MMSE), the Frontal Assessment Battery (FAB) as well as other measures of functional impairment and dementia severity (MMSE: r = -0.70; FAB: r = -0.65; Functional Assessment Questionnaire: r = 0.77; Instrumental Activities of Daily Living Scale: r = -0.75; Clinical Dementia Rating Scale: r = 0.72; p questions to the ADLQ, our experience suggested that this has to be done cautiously, since the sensitivity of these additional items could vary in different populations. The T-ADLQ needs to be validated in a different population of dementia subjects. Copyright © 2012 S. Karger AG, Basel.

  13. High Reliability Pediatric Septic Shock Quality Improvement Initiative and Decreasing Mortality.

    Science.gov (United States)

    Lane, Roni D; Funai, Tomohiko; Reeder, Ron; Larsen, Gitte Y

    2016-10-01

    Septic shock impacts mortality, morbidity, and health care costs. A quality improvement (QI) initiative was launched to improve early recognition and timely treatment of patients with septic shock in a pediatric emergency department (PED). Our primary aim was to describe the longitudinal effectiveness of the program, iterative changes in clinical practice, and associated outcomes. We implemented multiple interventions during our QI initiative (February 2007 to December 2014). Analysis of compliance and outcomes focused on a bundle consisting of: (1) timely antibiotics, (2) intravenous fluids (IVF) for rapid reversal of perfusion abnormalities and/or hypotension. Logistic regression was used to obtain adjusted odds ratios (ORs) for death and pediatric ICU (PICU) admission. A total of 1380 patients were treated for septic shock; 93% met screening criteria at triage. Implementation of the various processes improved timely interventions. One example included implementation of a sepsis order set, after which the mean proportion of patients receiving timely antibiotics increased to its highest rate. The odds of death were 5 times as high for children who did not receive bundle-compliant care (OR, 5.0 [95% Confidence Interval 1.9, 14.3]) compared with those who did (OR, 0.20 [95% Confidence Interval 0.07, 0.53]). Among PICU admitted patients, the odds of mortality were greater for children who presented with abnormal mental status and a higher pediatric index of mortality 2 score. QI methodology improved septic shock program goal adherence and decreased mortality without increasing PICU admissions or PED length of stay over the 8-year period, supporting continued emphasis on early recognition, timely IVF resuscitation, and antibiotic administration. Copyright © 2016 by the American Academy of Pediatrics.

  14. Numerical Simulations of Subscale Wind Turbine Rotor Inboard Airfoils at Low Reynolds Number

    Energy Technology Data Exchange (ETDEWEB)

    Blaylock, Myra L. [Sandia National Lab. (SNL-CA), Livermore, CA (United States). Thermal/ Fluid Sciences & Engineering Dept.; Maniaci, David Charles [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States). Wind Energy Technologies Dept.; Resor, Brian R. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States). Wind Energy Technologies Dept.

    2015-04-01

    New blade designs are planned to support future research campaigns at the SWiFT facility in Lubbock, Texas. The sub-scale blades will reproduce specific aerodynamic characteristics of utility-scale rotors. Reynolds numbers for megawatt-, utility-scale rotors are generally above 2-8 million. The thickness of inboard airfoils for these large rotors are typically as high as 35-40%. The thickness and the proximity to three-dimensional flow of these airfoils present design and analysis challenges, even at the full scale. However, more than a decade of experience with the airfoils in numerical simulation, in the wind tunnel, and in the field has generated confidence in their performance. Reynolds number regimes for the sub-scale rotor are significantly lower for the inboard blade, ranging from 0.7 to 1 million. Performance of the thick airfoils in this regime is uncertain because of the lack of wind tunnel data and the inherent challenge associated with numerical simulations. This report documents efforts to determine the most capable analysis tools to support these simulations in an effort to improve understanding of the aerodynamic properties of thick airfoils in this Reynolds number regime. Numerical results from various codes of four airfoils are verified against previously published wind tunnel results where data at those Reynolds numbers are available. Results are then computed for other Reynolds numbers of interest.

  15. Cycle chemistry monitoring system as means of improving the reliability of the equipment at the power plants

    Science.gov (United States)

    Yegoshina, O. V.; Voronov, V. N.; Yarovoy, V. O.; Bolshakova, N. A.

    2017-11-01

    There are many problems in domestic energy at the present that require urgent solutions in the near future. One of these problems - the aging of the main and auxiliary equipment. Wear of equipment is the cause of decrease reliability and efficiency of power plants. Reliability of the equipment are associated with the introduction of cycle chemistry monitoring system. The most damageable equipment’s are boilers (52.2 %), turbines (12.6 %) and heating systems (12.3 %) according to the review of failure rate on the power plants. The most part of the damageability of the boiler is heated surfaces (73.2 %). According to the Russian technical requirements, the monitoring systems are responsible to reduce damageability the boiler heating surfaces and to increase the reliability of the equipment. All power units capacity of over 50 MW are equipped with cycle chemistry monitoring systems in order to maintain water chemistry within operating limits. The main idea of cycle chemistry monitoring systems is to improve water chemistry at power plants. According to the guidelines, cycle chemistry monitoring systems of a single unit depends on its type (drum or once-through boiler) and consists of: 20…50 parameters of on-line chemical analyzers; 20…30 «grab» sample analyses (daily) and about 15…20 on-line monitored operating parameters. The operator of modern power plant uses with many data at different points of steam/water cycle. Operators do not can estimate quality of the cycle chemistry due to the large volume of daily and every shift information and dispersion of data, lack of systematization. In this paper, an algorithm for calculating the quality index developed for improving control the water chemistry of the condensate, feed water and prevent scaling and corrosion in the steam/water cycle.

  16. IMPROVEMENT TO PIPELINE COMPRESSOR ENGINE RELIABILITY THROUGH RETROFIT MICRO-PILOT IGNITION SYSTEM-PHASE I

    Energy Technology Data Exchange (ETDEWEB)

    Ted Bestor

    2003-03-04

    This report documents the first year's effort towards a 3-year program to develop micropilot ignition systems for existing pipeline compressor engines. In essence, all Phase I goals and objectives were met. We intend to proceed with the Phase II research plan, as set forth by the applicable Research Management Plan. The objective for Phase I was to demonstrate the feasibility of micropilot ignition for large bore, slow speed engines operating at low compression ratios. The primary elements of Micropilot Phase I were to develop a single-cylinder test chamber to study the injection of pilot fuel into a combustion cylinder and to develop, install and test a multi-cylinder micropilot ignition system for a 4-cylinder, natural gas test engine. In all, there were twelve (12) tasks defined and executed to support these two (2) primarily elements in a stepwise fashion. Task-specific approaches and results are documented in this report. Research activities for Micropilot Phase I were conducted with the understanding that the efforts are expected to result in a commercial product to capture and disseminate the efficiency and environmental benefits of this new technology. An extensive state-of-art review was conducted to leverage the existing body of knowledge of micropilot ignition with respect to retrofit applications. Additionally, commercially-available fuel injection products were identified and applied to the program where appropriate. This approach will minimize the overall time-to-market requirements, while meeting performance and cost criteria. The four-cylinder prototype data was encouraging for the micro-pilot ignition technology when compared to spark ignition. Initial testing results showed: (1) Brake specific fuel consumption of natural gas was improved from standard spark ignition across the map, 1% at full load and 5% at 70% load. (2) 0% misfires for all points on micropilot ignition. Fuel savings were most likely due to this percent misfire improvement

  17. Improved resolution and reliability in dynamic PET using Bayesian regularization of MRTM2

    DEFF Research Database (Denmark)

    Agn, Mikael; Svarer, Claus; Frokjaer, Vibe G.

    2014-01-01

    model is compared to the conventional approach of improving the low signal-to-noise ratio of PET data, i.e., spatial filtering of each time frame independently by a Gaussian kernel. We show that the model handles high levels of noise better than the conventional approach, while at the same time......This paper presents a mathematical model that regularizes dynamic PET data by using a Bayesian framework. We base the model on the well known two-parameter multilinear reference tissue method MRTM2 and regularize on the assumption that spatially close regions have similar parameters. The developed...

  18. Improvement of Steam Turbine Operational Performance and Reliability with using Modern Information Technologies

    Science.gov (United States)

    Brezgin, V. I.; Brodov, Yu M.; Kultishev, A. Yu

    2017-11-01

    The report presents improvement methods review in the fields of the steam turbine units design and operation based on modern information technologies application. In accordance with the life cycle methodology support, a conceptual model of the information support system during life cycle main stages (LC) of steam turbine unit is suggested. A classifying system, which ensures the creation of sustainable information links between the engineer team (manufacture’s plant) and customer organizations (power plants), is proposed. Within report, the principle of parameterization expansion beyond the geometric constructions at the design and improvement process of steam turbine unit equipment is proposed, studied and justified. The report presents the steam turbine unit equipment design methodology based on the brand new oil-cooler design system that have been developed and implemented by authors. This design system combines the construction subsystem, which is characterized by extensive usage of family tables and templates, and computation subsystem, which includes a methodology for the thermal-hydraulic zone-by-zone oil coolers design calculations. The report presents data about the developed software for operational monitoring, assessment of equipment parameters features as well as its implementation on five power plants.

  19. Reliable B Cell Epitope Predictions: Impacts of Method Development and Improved Benchmarking

    Science.gov (United States)

    Kringelum, Jens Vindahl; Lundegaard, Claus; Lund, Ole; Nielsen, Morten

    2012-01-01

    The interaction between antibodies and antigens is one of the most important immune system mechanisms for clearing infectious organisms from the host. Antibodies bind to antigens at sites referred to as B-cell epitopes. Identification of the exact location of B-cell epitopes is essential in several biomedical applications such as; rational vaccine design, development of disease diagnostics and immunotherapeutics. However, experimental mapping of epitopes is resource intensive making in silico methods an appealing complementary approach. To date, the reported performance of methods for in silico mapping of B-cell epitopes has been moderate. Several issues regarding the evaluation data sets may however have led to the performance values being underestimated: Rarely, all potential epitopes have been mapped on an antigen, and antibodies are generally raised against the antigen in a given biological context not against the antigen monomer. Improper dealing with these aspects leads to many artificial false positive predictions and hence to incorrect low performance values. To demonstrate the impact of proper benchmark definitions, we here present an updated version of the DiscoTope method incorporating a novel spatial neighborhood definition and half-sphere exposure as surface measure. Compared to other state-of-the-art prediction methods, Discotope-2.0 displayed improved performance both in cross-validation and in independent evaluations. Using DiscoTope-2.0, we assessed the impact on performance when using proper benchmark definitions. For 13 proteins in the training data set where sufficient biological information was available to make a proper benchmark redefinition, the average AUC performance was improved from 0.791 to 0.824. Similarly, the average AUC performance on an independent evaluation data set improved from 0.712 to 0.727. Our results thus demonstrate that given proper benchmark definitions, B-cell epitope prediction methods achieve highly significant

  20. Improved Mechanical Performance Fracture Properties and Reliability of Radical-Cured Thermosets

    Energy Technology Data Exchange (ETDEWEB)

    Redline, Erica Marie [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Bolintineanu, Dan S. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Lane, J. Matthew [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Stevens, Mark J. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Alam, Todd M. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Celina, Mathias C. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2016-10-01

    The aim of this study was to alter polymerization chemistry to improve network homogeneity in free-radical crosslinked systems. It was hypothesized that a reduction in heterogeneity of the network would lead to improved mechanical performance. Experiments and simulations were carried out to investigate the connection between polymerization chemistry, network structure and mechanical properties. Experiments were conducted on two different monomer systems - the first is a single monomer system, urethane dimethacrylate (UDMA), and the second is a two-monomer system consisting of bisphenol A glycidyl dimethacrylate (BisGMA) and triethylene glycol dimethacrylate (TEGDMA) in a ratio of 70/30 BisGMA/TEGDMA by weight. The methacrylate systems were crosslinked using traditional radical polymeriza- tion (TRP) with azobisisobutyronitrile (AIBN) or benzoyl peroxide (BPO) as an initiator; TRP systems were used as the control. The monomers were also cross-linked using activator regenerated by electron transfer atom transfer radical polymerization (ARGET ATRP) as a type of controlled radical polymerization (CRP). FTIR and DSC were used to monitor reac- tion kinetics of the systems. The networks were analyzed using NMR, DSC, X-ray diffraction (XRD), atomic force microscopy (AFM), and small angle X-ray scattering (SAXS). These techniques were employed in an attempt to quantify differences between the traditional and controlled radical polymerizations. While a quantitative methodology for characterizing net- work morphology was not established, SAXS and AFM have shown some promising initial results. Additionally, differences in mechanical behavior were observed between traditional and controlled radical polymerized thermosets in the BisGMA/TEGDMA system but not in the UDMA materials; this finding may be the result of network ductility variations between the two materials. Coarse-grained molecular dynamics simulations employing a novel model of the CRP reaction were carried out for

  1. Improved Membrane-Based Sensor Network for Reliable Gas Monitoring in the Subsurface

    Directory of Open Access Journals (Sweden)

    Detlef Lazik

    2012-12-01

    Full Text Available A conceptually improved sensor network to monitor the partial pressure of CO2 in different soil horizons was designed. Consisting of five membrane-based linear sensors (line-sensors each with 10 m length, the set-up enables us to integrate over the locally fluctuating CO2 concentrations (typically lower 5%vol up to the meter-scale gaining valuable concentration means with a repetition time of about 1 min. Preparatory tests in the laboratory resulted in a unexpected highly increased accuracy of better than 0.03%vol with respect to the previously published 0.08%vol. Thereby, the statistical uncertainties (standard deviations of the line-sensors and the reference sensor (nondispersive infrared CO2-sensor were close to each other. Whereas the uncertainty of the reference increases with the measurement value, the line-sensors show an inverse uncertainty trend resulting in a comparatively enhanced accuracy for concentrations >1%vol. Furthermore, a method for in situ maintenance was developed, enabling a proof of sensor quality and its effective calibration without demounting the line-sensors from the soil which would disturb the established structures and ongoing processes.

  2. Improved Membrane-Based Sensor Network for Reliable Gas Monitoring in the Subsurface

    Science.gov (United States)

    Lazik, Detlef; Ebert, Sebastian

    2012-01-01

    A conceptually improved sensor network to monitor the partial pressure of CO2 in different soil horizons was designed. Consisting of five membrane-based linear sensors (line-sensors) each with 10 m length, the set-up enables us to integrate over the locally fluctuating CO2 concentrations (typically lower 5%vol) up to the meter-scale gaining valuable concentration means with a repetition time of about 1 min. Preparatory tests in the laboratory resulted in a unexpected highly increased accuracy of better than 0.03%vol with respect to the previously published 0.08%vol. Thereby, the statistical uncertainties (standard deviations) of the line-sensors and the reference sensor (nondispersive infrared CO2-sensor) were close to each other. Whereas the uncertainty of the reference increases with the measurement value, the line-sensors show an inverse uncertainty trend resulting in a comparatively enhanced accuracy for concentrations >1%vol. Furthermore, a method for in situ maintenance was developed, enabling a proof of sensor quality and its effective calibration without demounting the line-sensors from the soil which would disturb the established structures and ongoing processes. PMID:23235447

  3. Embedded Sensors and Controls to Improve Component Performance and Reliability -- Bench-scale Testbed Design Report

    Energy Technology Data Exchange (ETDEWEB)

    Melin, Alexander M. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Kisner, Roger A. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Drira, Anis [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Reed, Frederick K. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2015-09-01

    Embedded instrumentation and control systems that can operate in extreme environments are challenging due to restrictions on sensors and materials. As a part of the Department of Energy's Nuclear Energy Enabling Technology cross-cutting technology development programs Advanced Sensors and Instrumentation topic, this report details the design of a bench-scale embedded instrumentation and control testbed. The design goal of the bench-scale testbed is to build a re-configurable system that can rapidly deploy and test advanced control algorithms in a hardware in the loop setup. The bench-scale testbed will be designed as a fluid pump analog that uses active magnetic bearings to support the shaft. The testbed represents an application that would improve the efficiency and performance of high temperature (700 C) pumps for liquid salt reactors that operate in an extreme environment and provide many engineering challenges that can be overcome with embedded instrumentation and control. This report will give details of the mechanical design, electromagnetic design, geometry optimization, power electronics design, and initial control system design.

  4. Designing interlayers to improve the mechanical reliability of transparent conductive oxide coatings on flexible substrates

    Science.gov (United States)

    Kim, Eun-Hye; Yang, Chan-Woo; Park, Jin-Woo

    2012-05-01

    In this study, we investigate the effect of interlayers on the mechanical properties of transparent conductive oxide (TCO) on flexible polymer substrates. Indium tin oxide (ITO), which is the most widely used TCO film, and Ti, which is the most widely used adhesive interlayer, are selected as the coating and the interlayer, respectively. These films are deposited on the polymer substrates using dc-magnetron sputtering to achieve varying thicknesses. The changes in the following critical factors for film cracking and delamination are analyzed: the internal stress (σi) induced in the coatings during deposition using a white light interferometer, the crystallinity using a transmission electron microscope, and the surface roughness of ITO caused by the interlayer using an atomic force microscope. The resistances to the cracking and delamination of ITO are evaluated using a fragmentation test. Our tests and analyses reveal the important role of the interlayers, which significantly reduce the compressive σi that is induced in the ITO and increase the resistance to the buckling delamination of the ITO. However, the relaxation of σi is not beneficial to cracking because there is less compensation for the external tension as σi further decreases. Based on these results, the microstructural control is revealed as a more influential factor than σi for improving crack resistance.

  5. Improvement in Device Performance and Reliability of Organic Light-Emitting Diodes through Deposition Rate Control

    Directory of Open Access Journals (Sweden)

    Shun-Wei Liu

    2014-01-01

    Full Text Available We demonstrated a fabrication technique to reduce the driving voltage, increase the current efficiency, and extend the operating lifetime of an organic light-emitting diode (OLED by simply controlling the deposition rate of bis(10-hydroxybenzo[h]qinolinato beryllium (Bebq2 used as the emitting layer and the electron-transport layer. In our optimized device, 55 nm of Bebq2 was first deposited at a faster deposition rate of 1.3 nm/s, followed by the deposition of a thin Bebq2 (5 nm layer at a slower rate of 0.03 nm/s. The Bebq2 layer with the faster deposition rate exhibited higher photoluminescence efficiency and was suitable for use in light emission. The thin Bebq2 layer with the slower deposition rate was used to modify the interface between the Bebq2 and cathode and hence improve the injection efficiency and lower the driving voltage. The operating lifetime of such a two-step deposition OLED was 1.92 and 4.6 times longer than that of devices with a single deposition rate, that is, 1.3 and 0.03 nm/s cases, respectively.

  6. Designing and Assessing the Validity and Reliability of the Hospital Readiness Assessment Tools to Conducting Quality Improvement Program

    Directory of Open Access Journals (Sweden)

    Kamal Gholipoor

    2016-09-01

    Full Text Available Background and objectives : Identifying the readiness of hospital and its strengths and weaknesses can be useful in developing appropriate planning and situation analyses and management to getting effective in clinical audit programs. The aim of this study was to design and assess the validity of the Hospital Readiness Assessment Tools to conduct quality improvement and clinical audit programs. Material and Methods: In this study, based on the results of a systematic review of literature, an initial questionnaire with 77 items was designed. Questionnaire content validity was reviewed by experts in the field of hospital management and quality improvement in Tabriz University of Medical Sciences. For this purpose, 20 questionnaires were sent to experts. Finally, 15 participants returned completed questionnaire. Questionnaire validity was reviewed and confirmed based on Content Validity Index and Content Validity Ratio. Questionnaire reliability was confirmed based on Cronbach's alpha index (α = 0.96 in a pilot study by participation of 30 hospital managers. Results: The results showed that the final questionnaire contains 54 questions as nine category as: data and information (9 items, teamwork (12 questions, resources (5 questions, patient and education (5, intervention design and implementation (5 questions, clinical audit management (4 questions, human resources (6 questions, evidence and standard (4 items and evaluation and feedback (4 items. The final questionnaire content validity index was 0.91 and final questionnaire Cronbach's alpha coefficient was 0.96. Conclusion: Considering the relative good validity and reliability of the designed tool in this study, it appears that the questionnaire can be used to identify and assess the readiness of hospitals for quality improvement and clinical audit program implementation

  7. Routes to improving the reliability of low level DNA analysis using real-time PCR

    Directory of Open Access Journals (Sweden)

    Burns Malcolm J

    2006-07-01

    Full Text Available Abstract Background Accurate quantification of DNA using quantitative real-time PCR at low levels is increasingly important for clinical, environmental and forensic applications. At low concentration levels (here referring to under 100 target copies DNA quantification is sensitive to losses during preparation, and suffers from appreciable valid non-detection rates for sampling reasons. This paper reports studies on a real-time quantitative PCR assay targeting a region of the human SRY gene over a concentration range of 0.5 to 1000 target copies. The effects of different sample preparation and calibration methods on quantitative accuracy were investigated. Results At very low target concentrations of 0.5–10 genome equivalents (g.e. eliminating any replicates within each DNA standard concentration with no measurable signal (non-detects compromised calibration. Improved calibration could be achieved by eliminating all calibration replicates for any calibration standard concentration with non-detects ('elimination by sample'. Test samples also showed positive bias if non-detects were removed prior to averaging; less biased results were obtained by converting to concentration, including non-detects as zero concentration, and averaging all values. Tube plastic proved to have a strongly significant effect on DNA quantitation at low levels (p = 1.8 × 10-4. At low concentrations (under 10 g.e., results for assays prepared in standard plastic were reduced by about 50% compared to the low-retention plastic. Preparation solution (carrier DNA or stabiliser was not found to have a significant effect in this study. Detection probabilities were calculated using logistic regression. Logistic regression over large concentration ranges proved sensitive to non-detected replicate reactions due to amplification failure at high concentrations; the effect could be reduced by regression against log (concentration or, better, by eliminating invalid responses

  8. Optimal distributed generation placement in distribution system to improve reliability and critical loads pick up after natural disasters

    Directory of Open Access Journals (Sweden)

    Galiveeti Hemakumar Reddy

    2017-06-01

    Full Text Available The increase in frequency of natural disasters has necessitated the need of resilient distribution systems. Natural disasters lead to severe damage of power system infrastructure and the main grid may not be available to serve the loads. The integration of distributed generation (DG into distribution system partially restores the loads after natural disasters and improves the reliability during normal operating conditions. After a natural disaster, objective of the system operators is to restore the critical loads as a priority. This enables the need of considering critical load pick up as an objective function while placing the DGs. A location based constraint is, thus, required to make sure the DGs are available to pick up the loads after natural disasters. Fuzzy multi criteria decision making (FMCDM approach is used in this work to rank the load points and locations/feeder sections. This paper uses particle swarm optimization (PSO to evaluate the optimal size and location of DGs using the proposed objective function. The obtained results are compared with the results of reliability as an objective function.

  9. Applying posttraumatic stress disorder MMPI subscale to World War II POW veterans.

    Science.gov (United States)

    Query, W T; Megran, J; McDonald, G

    1986-03-01

    In order to determine whether the MMPI-PTSD subscale has application for assessing DSM-III diagnosed PTSD among populations other than Vietnam veterans, a group of WWII POWs (N = 69) were given the subscale. Results indicated that the use of the PTSD subscale can be generalized to older veterans; in a small sample of Pacific POWs, PTSD is more common among those from the Pacific theater than those from Europe. However, the subscale fails to distinguish between Pacific and European POW veterans. Difficulties in sampling and confounding stressors are discussed, as well as implications for treatment of WWII veterans.

  10. USING A TOTAL QUALITY STRATEGY IN A NEW PRACTICAL APPROACH FOR IMPROVING THE PRODUCT RELIABILITY IN AUTOMOTIVE INDUSTRY

    Directory of Open Access Journals (Sweden)

    Cristiano Fragassa

    2014-09-01

    Full Text Available In this paper a Total Quality Management strategy is proposed, refined and used with the aim at improving the quality of large-mass industrial products far beyond the technical specifications demanded at the end-customer level. This approach combines standard and non-standard tools used for Reliability, Availability and Maintainability analysis. The procedure also realizes a stricter correlation between theoretical evaluation methods and experimental evidences as part of a modern integrated method for strengthening quality in design and process. A commercial Intake Manifold, largely spread in the market, is used as test-case for the validation of the methodology. As general additional result, the research underlines the impact of Total Quality Management and its tools on the development of innovation.

  11. Data Transformation for Confidence Interval Improvement: An Application to the Estimation of Stress-Strength Model Reliability

    Directory of Open Access Journals (Sweden)

    Alessandro Barbiero

    2014-01-01

    Full Text Available In many statistical applications, it is often necessary to obtain an interval estimate for an unknown proportion or probability or, more generally, for a parameter whose natural space is the unit interval. The customary approximate two-sided confidence interval for such a parameter, based on some version of the central limit theorem, is known to be unsatisfactory when its true value is close to zero or one or when the sample size is small. A possible way to tackle this issue is the transformation of the data through a proper function that is able to make the approximation to the normal distribution less coarse. In this paper, we study the application of several of these transformations to the context of the estimation of the reliability parameter for stress-strength models, with a special focus on Poisson distribution. From this work, some practical hints emerge on which transformation may more efficiently improve standard confidence intervals in which scenarios.

  12. Subscale and Full-Scale Testing of Buckling-Critical Launch Vehicle Shell Structures

    Science.gov (United States)

    Hilburger, Mark W.; Haynie, Waddy T.; Lovejoy, Andrew E.; Roberts, Michael G.; Norris, Jeffery P.; Waters, W. Allen; Herring, Helen M.

    2012-01-01

    New analysis-based shell buckling design factors (aka knockdown factors), along with associated design and analysis technologies, are being developed by NASA for the design of launch vehicle structures. Preliminary design studies indicate that implementation of these new knockdown factors can enable significant reductions in mass and mass-growth in these vehicles and can help mitigate some of NASA s launch vehicle development and performance risks by reducing the reliance on testing, providing high-fidelity estimates of structural performance, reliability, robustness, and enable increased payload capability. However, in order to validate any new analysis-based design data or methods, a series of carefully designed and executed structural tests are required at both the subscale and full-scale level. This paper describes recent buckling test efforts at NASA on two different orthogrid-stiffened metallic cylindrical shell test articles. One of the test articles was an 8-ft-diameter orthogrid-stiffened cylinder and was subjected to an axial compression load. The second test article was a 27.5-ft-diameter Space Shuttle External Tank-derived cylinder and was subjected to combined internal pressure and axial compression.

  13. Improved Method for Reliable HMW-GS Identification by RP-HPLC and SDS-PAGE in Common Wheat Cultivars.

    Science.gov (United States)

    Jang, You-Ran; Beom, Hye-Rang; Altenbach, Susan B; Lee, Min-Ki; Lim, Sun-Hyung; Lee, Jong-Yeol

    2017-06-24

    The accurate identification of alleles for high-molecular weight glutenins (HMW-GS) is critical for wheat breeding programs targeting end-use quality. RP-HPLC methods were optimized for separation of HMW-GS, resulting in enhanced resolution of 1By and 1Dx subunits. Statistically significant differences in retention times (RTs) for subunits corresponding to HMW-GS alleles were determined using 16 standard wheat cultivars with known HMW-GS compositions. Subunits that were not identified unambiguously by RP-HPLC were distinguished by SDS-PAGE or inferred from association with linked subunits. The method was used to verify the allelic compositions of 32 Korean wheat cultivars previously determined using SDS-PAGE and to assess the compositions of six new Korean cultivars. Three cultivars contained subunits that were identified incorrectly in the earlier analysis. The improved RP-HPLC method combined with conventional SDS-PAGE provides for accurate, efficient and reliable identification of HMW-GS and will contribute to efforts to improve wheat end-use quality.

  14. Cost and Reliability Improvement for CIGS-Based PV on Flexible Substrate: May 24, 2006 -- July 31, 2010

    Energy Technology Data Exchange (ETDEWEB)

    Wiedeman, S.

    2011-05-01

    Global Solar Energy rapidly advances the cost and performance of commercial thin-film CIGS products using roll-to-roll processing on steel foil substrate in compact, low cost deposition equipment, with in-situ sensors for real-time intelligent process control. Substantial increases in power module efficiency, which now exceed 13%, are evident at GSE factories in two countries with a combined capacity greater than 75 MW. During 2009 the average efficiency of cell strings (3780 cm2) was increased from 7% to over 11%, with champion results exceeding 13% Continued testing of module reliability in rigid product has reaffirmed extended life expectancy for standard glass product, and has qualified additional lower-cost methods and materials. Expected lifetime for PV in flexible packages continues to increase as failure mechanisms are elucidated, and resolved by better methods and materials. Cost reduction has been achieved through better materials utilization, enhanced vendor and material qualification and selection. The largest cost gains have come as a result of higher cell conversion efficiency and yields, higher processing rates, greater automation and improved control in all process steps. These improvements are integral to this thin film PV partnership program, and all realized with the 'Gen2' manufacturing plants, processes and equipment.

  15. Increasing the Precision of Subscale Scores by Using Out-of-Scale Information

    Science.gov (United States)

    Kahraman, Nilufer; Kamata, Akihito

    2004-01-01

    In this study, the precision of subscale score estimates was evaluated when out-of-scale information was incorporated. Procedures that incorporated out-of-scale information and only information within a subscale were compared through a series of simulations. It was revealed that more information (i.e., more precision) was always provided for…

  16. Effects of microstructural control on the failure kinetics and the reliability improvement of Al and Al-alloy interconnects

    Energy Technology Data Exchange (ETDEWEB)

    Kang, Seung Hyuk [Univ. of California, Berkeley, CA (United States)

    1996-12-01

    The reliability of microelectronic systems is often limited by electromigration failure in Al-based thin-film conducting lines which interconnect devices to form an integrated circuit. Under an applied electric field Al atoms migrate with the electron flow, causing a counterflow of vacancies that accumulate into voids, eventually leading to an open circuit failure. The work reported here is concerned with clarifying the microstructural mechanism of electromigration failure, and with developing a metallurgical method to improve the electromigration resistance of Al-based interconnects. Pure Al, Al-2Cu, and Al-2Cu-1Si lines with quasi-bamboo microstructures are explored as a function of heat treatment conditions and current density. The "weakest" microstructural unit that causes failure is identified by electron microscopy; with rare exceptions, failure occurs at the upstream end of the longest polygranular segment in a given line. This microstructural characteristic of electromigration failure is even observed in lines whose maximum segment lengths are less than a few microns. The time to failure appears to increase exponentially with decreasing longest polygranular segment length. A simple constitutive equation is reported to describe the failure kinetics as a function of the polygranular segment length that leads to failure. Given correct values of the kinetic constants included in the equation, this microstructure-based constitutive relation will provide a way to assess interconnect reliability. An effective metallurgical method that can eliminate relatively long polygranular segments is post-pattern annealing. This heat treatment particularly narrows the distribution of the longest polygranular segment lengths over a large set of lines. As a consequence, the time-to-failure distribution narrows as well, so that the time to first failure increases more substantially than the median time to failure.

  17. The Reliability Improvement of Cu Interconnection by the Control of Crystallized α-Ta/TaNx Diffusion Barrier

    Directory of Open Access Journals (Sweden)

    Wei-Lin Wang

    2015-01-01

    Full Text Available Ta/TaN bilayers have been deposited by a commercial self-ionized plasma (SIP system. The microstructures of Ta/TaN bilayers have been systematically characterized by X-ray diffraction patterns and cross-sectional transmission electron microscopy. TaN films deposited by SIP system are amorphous. The crystalline behavior of Ta film can be controlled by the N concentration of underlying TaN film. On amorphous TaN film with low N concentration, overdeposited Ta film is the mixture of α- and β-phases with amorphous-like structure. Increasing the N concentration of amorphous TaN underlayer successfully leads upper Ta film to form pure α-phase. For the practical application, the electrical property and reliability of Cu interconnection structure have been investigated by utilizing various types of Ta/TaN diffusion barrier. The diffusion barrier fabricated by the combination of crystallized α-Ta and TaN with high N concentration efficiently reduces the KRc and improves the EM resistance of Cu interconnection structure.

  18. Comprehensive automation and monitoring of MV grids as the key element of improvement of energy supply reliability and continuity

    Directory of Open Access Journals (Sweden)

    Stanisław Kubacki

    2012-03-01

    Full Text Available The paper presents the issue of comprehensive automation and monitoring of medium voltage (MV grids as a key element of the Smart Grid concept. The existing condition of MV grid control and monitoring is discussed, and the concept of a solution which will provide the possibility of remote automatic grid reconfiguration and ensure full grid observability from the dispatching system level is introduced. Automation of MV grid switching is discussed in detail to isolate a faulty line section and supply electricity at the time of the failure to the largest possible number of recipients. An example of such automation controls’ operation is also presented. The paper’s second part presents the key role of the quick fault location function and the possibility of the MV grid’s remote reconfiguration for improving power supply reliability (SAIDI and SAIFI indices. It is also shown how an increase in the number of points fitted with faulted circuit indicators with the option of remote control of switches from the dispatch system in MV grids may affect reduction of SAIDI and SAIFI indices across ENERGA-OPERATOR SA divisions.

  19. A rapid, automated VWF ristocetin cofactor activity assay improves reliability in the diagnosis of Von Willebrand disease.

    Science.gov (United States)

    Bowyer, Annette E; Shepherd, Fiona; Kitchen, Stephen; Makris, Michael

    2011-04-01

    The effective diagnosis and monitoring of Von Willebrand Disease (VWD) requires an accurate assessment of ristocetin co-factor activity (VWF:RCo). Current methodologies include automated platelet aggregometry and manual visual agglutination both of which are laborious to perform and notoriously subject to a high degree of inter and intra assay variation. We have evaluated an automated VWF:RCo assay (BC Von Willebrand Reagent, Siemens, Marberg, Germany) for use on the Sysmex CS2100i analyser (Milton Keynes, UK) and retrospectively compared the results with an in-house manual visual agglutination assay and VWF antigen (Siemens) in normal subjects and in 53 patients with various types of VWD and 23 patients following VWF therapeutic treatment. The intra and interassay CV was improved with the automated assay (2.3% and 3.8% respectively) compared to 7% with the manual VWF:RCo assay. Good correlation was found between the two assays (r=0.91) in 53 patients with VWD. The mean manual VWF:RCo was 0.25IU/ml and mean automated VWF:RCo was 0.27IU/ml. A comparable increase in VWF:RCo following treatment, mostly with Desmopressin, was found in 13 patients with type 1 VWD (mean 3.9 fold increase with manual VWF:RCo and 3.1 fold with the automated VWF:RCo). In 13 patients with type 2 or 3 VWD following treatment mostly with concentrate , a higher increase was found with the automated VWF:RCo assay than the manual assay (mean 11.9 fold manually and mean 20.3 automated). The automated VWF:RCo assay shows enhanced precision and analysis time in this difficult and time consuming laboratory test and its introduction should greatly improve the reliability of VWF testing. Copyright © 2010. Published by Elsevier Ltd.

  20. METHODS OF IMPROVING THE RELIABILITY OF THE CONTROL SYSTEM TRACTION POWER SUPPLY OF ELECTRIC TRANSPORT BASED ON AN EXPERT INFORMATION

    Directory of Open Access Journals (Sweden)

    O. O. Matusevych

    2009-03-01

    Full Text Available The author proposed the numerous methods of solving the multi-criterion task – increasing of reliability of control system on the basis of expert information. The information, which allows choosing thoughtfully the method of reliability increasing for a control system of electric transport, is considered.

  1. An alternative to the balance error scoring system: using a low-cost balance board to improve the validity/reliability of sports-related concussion balance testing.

    Science.gov (United States)

    Chang, Jasper O; Levy, Susan S; Seay, Seth W; Goble, Daniel J

    2014-05-01

    Recent guidelines advocate sports medicine professionals to use balance tests to assess sensorimotor status in the management of concussions. The present study sought to determine whether a low-cost balance board could provide a valid, reliable, and objective means of performing this balance testing. Criterion validity testing relative to a gold standard and 7 day test-retest reliability. University biomechanics laboratory. Thirty healthy young adults. Balance ability was assessed on 2 days separated by 1 week using (1) a gold standard measure (ie, scientific grade force plate), (2) a low-cost Nintendo Wii Balance Board (WBB), and (3) the Balance Error Scoring System (BESS). Validity of the WBB center of pressure path length and BESS scores were determined relative to the force plate data. Test-retest reliability was established based on intraclass correlation coefficients. Composite scores for the WBB had excellent validity (r = 0.99) and test-retest reliability (R = 0.88). Both the validity (r = 0.10-0.52) and test-retest reliability (r = 0.61-0.78) were lower for the BESS. These findings demonstrate that a low-cost balance board can provide improved balance testing accuracy/reliability compared with the BESS. This approach provides a potentially more valid/reliable, yet affordable, means of assessing sports-related concussion compared with current methods.

  2. Improving the Reliability of Network Metrics in Structural Brain Networks by Integrating Different Network Weighting Strategies into a Single Graph

    Directory of Open Access Journals (Sweden)

    Stavros I. Dimitriadis

    2017-12-01

    Full Text Available Structural brain networks estimated from diffusion MRI (dMRI via tractography have been widely studied in healthy controls and patients with neurological and psychiatric diseases. However, few studies have addressed the reliability of derived network metrics both node-specific and network-wide. Different network weighting strategies (NWS can be adopted to weight the strength of connection between two nodes yielding structural brain networks that are almost fully-weighted. Here, we scanned five healthy participants five times each, using a diffusion-weighted MRI protocol and computed edges between 90 regions of interest (ROI from the Automated Anatomical Labeling (AAL template. The edges were weighted according to nine different methods. We propose a linear combination of these nine NWS into a single graph using an appropriate diffusion distance metric. We refer to the resulting weighted graph as an Integrated Weighted Structural Brain Network (ISWBN. Additionally, we consider a topological filtering scheme that maximizes the information flow in the brain network under the constraint of the overall cost of the surviving connections. We compared each of the nine NWS and the ISWBN based on the improvement of: (a intra-class correlation coefficient (ICC of well-known network metrics, both node-wise and per network level; and (b the recognition accuracy of each subject compared to the remainder of the cohort, as an attempt to access the uniqueness of the structural brain network for each subject, after first applying our proposed topological filtering scheme. Based on a threshold where the network level ICC should be >0.90, our findings revealed that six out of nine NWS lead to unreliable results at the network level, while all nine NWS were unreliable at the node level. In comparison, our proposed ISWBN performed as well as the best performing individual NWS at the network level, and the ICC was higher compared to all individual NWS at the node

  3. Improving the quality of discrete-choice experiments in health: how can we assess validity and reliability?

    Science.gov (United States)

    Janssen, Ellen M; Marshall, Deborah A; Hauber, A Brett; Bridges, John F P

    2017-12-01

    The recent endorsement of discrete-choice experiments (DCEs) and other stated-preference methods by regulatory and health technology assessment (HTA) agencies has placed a greater focus on demonstrating the validity and reliability of preference results. Areas covered: We present a practical overview of tests of validity and reliability that have been applied in the health DCE literature and explore other study qualities of DCEs. From the published literature, we identify a variety of methods to assess the validity and reliability of DCEs. We conceptualize these methods to create a conceptual model with four domains: measurement validity, measurement reliability, choice validity, and choice reliability. Each domain consists of three categories that can be assessed using one to four procedures (for a total of 24 tests). We present how these tests have been applied in the literature and direct readers to applications of these tests in the health DCE literature. Based on a stakeholder engagement exercise, we consider the importance of study characteristics beyond traditional concepts of validity and reliability. Expert commentary: We discuss study design considerations to assess the validity and reliability of a DCE, consider limitations to the current application of tests, and discuss future work to consider the quality of DCEs in healthcare.

  4. Improving model prediction reliability through enhanced representation of wetland soil processes and constrained model auto calibration - A paired watershed study

    Science.gov (United States)

    Sharifi, Amirreza; Lang, Megan W.; McCarty, Gregory W.; Sadeghi, Ali M.; Lee, Sangchul; Yen, Haw; Rabenhorst, Martin C.; Jeong, Jaehak; Yeo, In-Young

    2016-10-01

    Process based, distributed watershed models possess a large number of parameters that are not directly measured in field and need to be calibrated, in most cases through matching modeled in-stream fluxes with monitored data. Recently, concern has been raised regarding the reliability of this common calibration practice, because models that are deemed to be adequately calibrated based on commonly used metrics (e.g., Nash Sutcliffe efficiency) may not realistically represent intra-watershed responses or fluxes. Such shortcomings stem from the use of an evaluation criteria that only concerns the global in-stream responses of the model without investigating intra-watershed responses. In this study, we introduce a modification to the Soil and Water Assessment Tool (SWAT) model, and a new calibration technique that collectively reduce the chance of misrepresenting intra-watershed responses. The SWAT model was modified to better represent NO3 cycling in soils with various degrees of water holding capacity. The new calibration tool has the capacity to calibrate paired watersheds simultaneously within a single framework. It was found that when both proposed methodologies were applied jointly to two paired watersheds on the Delmarva Peninsula, the performance of the models as judged based on conventional metrics suffered, however, the intra-watershed responses (e.g., mass of NO3 lost to denitrification) in the two models automatically converged to realistic sums. This approach also demonstrates the capacity to spatially distinguish areas of high denitrification potential, an ability that has implications for improved management of prior converted wetlands under crop production and for identifying prominent areas for wetland restoration.

  5. "Moved by the spirit": does spirituality moderate the interrelationships between subjective well-being subscales?

    Science.gov (United States)

    Schuurmans-Stekhoven, James

    2010-07-01

    Despite the recent escalation of research into the spirituality and well-being link, past efforts have been plagued by methodological problems. However, the potential for measurement error within psychometric instruments remains largely unexplored. After reviewing theory and evidence suggesting spirituality might represent an affective misattribution, moderation modeling-with each subjective well-being (SWB) subscale as a dependent variable as predicted by the remaining SWB subscales-is utilized to test the assumption of scale invariance. These interrelationships were shown to vary in conjunction with spirituality; that is the analysis revealed significant spirituality x subscale interactions. Importantly, in all models the spirituality main effect was either nonsignificant or accounted for by other predictors. In combination, the findings suggest the interrelationship between the subscales rather than the level of SWB varies systematically with spirituality and casts considerable doubt on the previously reported "belief-as-benefit" effect.

  6. Reliability generalization of the Texas Revised Inventory of Grief (TRIG).

    Science.gov (United States)

    Montano, Samuel A; Lewey, Jennifer H; O'Toole, Siobhan K; Graves, Douglas

    2016-01-01

    While grief is a universal experience, this phenomenon is experienced in a variety of ways largely dependent upon one's cultural schema. To consider the potential problems inherent in generalizing the results of an assessment tool across cultures, this study explores the notion of generalizability in assessment by evaluating the reliability of the Texas Revised Inventory of Grief (TRIG) using a meta-analytic technique called reliability generalization. The TRIG demonstrated strong reliability with mean Cronbach's alphas of .90 and .82 for the present and past subscales, respectively. Overall, the TRIG, especially the present subscale, appears to produce reliable scores even across cultures.

  7. The Correlation of SCL-90-R Anxiety, Depression, Somatization Subscale Scores with Chronic Low Back Pain.

    Science.gov (United States)

    Adilay, Utku; Guclu, Bulent; Goksel, Murat; Keskil, Semih

    2017-02-07

    The aim of this study was to investigate the correlation of the Symptom Checklist-90-R (SCL-90-R) anxiety, depression, and somatization subscale scores with chronic low back pain. In this study, 75 patients admitted with the complaint of chronic low back pain (patient group) and 75 healthy persons (control group) were evaluated. SCL-90-R anxiety, depression, and somatization subscale scores of patients having chronic low back pain and healthy persons were measured. The mean values were paired and using two tailed t test they were statistically evaluated. The difference between SCL-90-R anxiety subscale subscores of patients having choronic low back pain and healthy persons was statistically non significant (p 0.05).The difference betweenSCL-90-R depression subscale subscores of patients having chronic low back pain and healthy persons was statistically non significant (p 0.05). The difference between SCL-90-R somatization subscale subscores of patients having chronic low back pain and healthy persons was statistically significant (p 0.05). Our data show that SCL-90-R somatization subscale subscores were higher in patients with low back pain. The treatment of low back pain can be more successful when combined with the treatment of somatization.

  8. The Subjective Index for Physical and Social Outcome (SIPSO in Stroke: investigation of its subscale structure

    Directory of Open Access Journals (Sweden)

    George Steve

    2010-04-01

    Full Text Available Abstract Background Short and valid measures of the impact of a stroke on integration are required in health and social settings. The Subjective Index of Physical and Social Outcome (SIPSO is one such measure. However, there are questions whether scores can be summed into a total score or whether subscale scores should be calculated. This paper aims to provide clarity on the internal construct validity of the subscales and the total scale. Methods SIPSO data were collected as part of two parallel surveys of the met and unmet needs of 445 younger people (aged 18-65 with non-recent stroke (at least one year and living at home. Factor, Mokken and Rasch analysis were used. Results Factor analysis supported a two factor structure (explaining 68% of the variance as did the Mokken analysis (overall Loevinger coefficient 0.77 for the Physical Integration subscale; 0.51 for the Social Integration subscale. Both subscales fitted the Rasch model (P > 0.01 after adjusting for some observed differential item functioning. The 10-items together did not fit the Rasch model. Conclusions The SIPSO subscales are valid for use with stroke patients of working age but the total SIPSO is not. The conversion table can be used by clinicians and researchers to convert ordinal data to interval level prior to mathematical operations and other parametric procedures. Further work is required to explore the occurrence of bias by gender for some of the items.

  9. An Investigation of the Reliability of Knowledge Measures Through Relational Mapping in Joint Military Environments: Knowledge, Models and Tools to Improve the Effectiveness of Naval Distance Learning

    Science.gov (United States)

    2006-06-01

    v Introduction...Tools to Improve the Effectiveness of Naval Distance Learning v AN INVESTIGATION OF THE RELIABILITY OF KNOWLEDGE MEASURES THROUGH RELATIONAL MAPPING IN...Klein (1999). SNovak and Gowin (1984). Shavelson (Ruiz-Primo, Schultz, Li, & Shavelson, 2001) Referent-based Compares the network Compares the semantic

  10. Fatigue life prediction of liquid rocket engine combustor with subscale test verification

    Science.gov (United States)

    Sung, In-Kyung

    Reusable rocket systems such as the Space Shuttle introduced a new era in propulsion system design for economic feasibility. Practical reusable systems require an order of magnitude increase in life. To achieve this improved methods are needed to assess failure mechanisms and to predict life cycles of rocket combustor. A general goal of the research was to demonstrate the use of subscale rocket combustor prototype in a cost-effective test program. Life limiting factors and metal behaviors under repeated loads were surveyed and reviewed. The life prediction theories are presented, with an emphasis on studies that used subscale test hardware for model validation. From this review, low cycle fatigue (LCF) and creep-fatigue interaction (ratcheting) were identified as the main life limiting factors of the combustor. Several life prediction methods such as conventional and advanced viscoplastic models were used to predict life cycle due to low cycle thermal stress, transient effects, and creep rupture damage. Creep-fatigue interaction and cyclic hardening were also investigated. A prediction method based on 2D beam theory was modified using 3D plate deformation theory to provide an extended prediction method. For experimental validation two small scale annular plug nozzle thrusters were designed, built and tested. The test article was composed of a water-cooled liner, plug annular nozzle and 200 psia precombustor that used decomposed hydrogen peroxide as the oxidizer and JP-8 as the fuel. The first combustor was tested cyclically at the Advanced Propellants and Combustion Laboratory at Purdue University. Testing was stopped after 140 cycles due to an unpredicted failure mechanism due to an increasing hot spot in the location where failure was predicted. A second combustor was designed to avoid the previous failure, however, it was over pressurized and deformed beyond repair during cold-flow test. The test results are discussed and compared to the analytical and numerical

  11. Improving the Efficiency of Administrative Decision-Making when Monitoring Reliability and Safety of Oil and Gas Equipment

    Directory of Open Access Journals (Sweden)

    Zemenkova Maria

    2016-01-01

    Full Text Available Methodology of rapid assessment of reliability index was developed based on system analysis of technological parameters. Within functioning of on-line monitoring system of reliability index of industrial facility this method allows to increase efficiency of making managerial decisions on technical and preventive maintenance. The technique is based on the analysis of technological parameters of operational modes of pipeline transport facilities registered by dispatcher controls. The created technique can be used by the operating, research, design institutes and oil and gas transport enterprises when declaring industrial safety. The received mathematical models allow federal services of supervision, the independent expert organizations to predict the development of reliability in the registered block of dispatching data either in real time mode, or taking into account the dynamics of service conditions of the object.

  12. High-Precise Gravity Observations at Archaeological Sites: How We Can Improve the Interpretation Effectiveness and Reliability?

    Science.gov (United States)

    Eppelbaum, Lev

    2015-04-01

    Microgravity investigations are comparatively rarely used for searching of hidden ancient targets (e.g., Eppelbaum, 2013). It is caused mainly by small geometric size of the desired archaeological objects and various types of noise complicating the observed useful signal. At the same time, development of modern generation of field gravimetric equipment allows to register microGal (10-8 m/s2) anomalies that offer a new challenge in this direction. Correspondingly, an accuracy of gravity variometers (gradientometers) is also sharply increased. How we can improve the interpretation effectiveness and reliability? Undoubtedly, it must be a multi-stage process. I believe that we must begin since nonconventional methodologies for reducing topographic effect and terrain correction computation. Topographic effect reducing The possibilities of reducing topographic effects by grouping the points of additional gravimetric observations around the central point located on the survey network were demonstrated in (Khesin et al., 1996). A group of 4 to 8 additional points is located above and below along the relief approximately symmetrically and equidistant from the central point. The topographic effect is reduced to the obtained difference between the gravity field in the center of the group and its mean value for the whole group. Application of this methodology in the gold-pyrite deposit Gyzyl-Bulakh (Lesser Caucasus, western Azerbaijan) indicated its effectiveness. Computation of terrain correction Some geophysicists compare the new ideas in the field of terrain correction (TC) in gravimetry with the 'perpetuum mobile' invention. However, when we speak about very detailed gravity observations, the problem of most optimal computation of surrounding relief influence is of a great importance. Let us will consider two approaches applied earlier in ore geophysics. First approach A first method was applied in the Gyzyl-Bulakh gold-pyrite deposit situated in the Mekhmana ore region of

  13. Improvement on the Accuracy and Reliability of Ultrasound Coronal Curvature Measurement on Adolescent Idiopathic Scoliosis With the Aid of Previous Radiographs.

    Science.gov (United States)

    Zheng, Rui; Young, Michelle; Hill, Douglas; Le, L H; Hedden, Douglas; Moreau, Marc; Mahood, James; Southon, Sarah; Lou, Edmond

    2016-03-01

    Retrospective study of the coronal curvature measurement on ultrasound (US) images with the aid of previous radiographs. To compare the reliability and accuracy of the coronal curvature measurements from US images on children who have adolescent idiopathic scoliosis (AIS) with and without the knowledge of previous radiographs. Using US imaging technique to measure coronal curvature on children with AIS has demonstrated high intra- and interrater reliabilities. However, the selection of end-vertebrae and the measurement difference between radiography and the US method were only moderately reliable. Two raters measured the coronal curvatures from 65 AIS standing US spine images, without (measured one time) and with the aid of previous standing radiographs (measured two times). The intra- and interrater reliability, the correlation and the difference between the radiographic and US measurements, and the error index of the end-vertebrae selection were assessed. Overall, 109 curves were investigated. The intraclass correlation coefficients (ICC) of intra- and interrater reliability of the US coronal curvature measurement with the aid of previous radiographs (AOR) were 0.95 and 0.91, respectively. In comparison with the radiographic measurements, the correlation of AOR method (R) was 0.90 and the MAD was 2.8°; the corresponding results of the US measurement without the AOR (blinded US method) were 0.73° and 4.8°, respectively. The average error index on end-vertebral selection improved 43% with the AOR. The AOR method significantly improved reliability and accuracy of the spinal curvature measurement on US images compared with the blinded US method (Pchildren with AIS. 3.

  14. Improvement of level-1 PSA computer code package - Modeling and analysis for dynamic reliability of nuclear power plants

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Chang Hoon; Baek, Sang Yeup; Shin, In Sup; Moon, Shin Myung; Moon, Jae Phil; Koo, Hoon Young; Kim, Ju Shin [Seoul National University, Seoul (Korea, Republic of); Hong, Jung Sik [Seoul National Polytechnology University, Seoul (Korea, Republic of); Lim, Tae Jin [Soongsil University, Seoul (Korea, Republic of)

    1996-08-01

    The objective of this project is to develop a methodology of the dynamic reliability analysis for NPP. The first year`s research was focused on developing a procedure for analyzing failure data of running components and a simulator for estimating the reliability of series-parallel structures. The second year`s research was concentrated on estimating the lifetime distribution and PM effect of a component from its failure data in various cases, and the lifetime distribution of a system with a particular structure. Computer codes for performing these jobs were also developed. The objectives of the third year`s research is to develop models for analyzing special failure types (CCFs, Standby redundant structure) that were nor considered in the first two years, and to complete a methodology of the dynamic reliability analysis for nuclear power plants. The analysis of failure data of components and related researches for supporting the simulator must be preceded for providing proper input to the simulator. Thus this research is divided into three major parts. 1. Analysis of the time dependent life distribution and the PM effect. 2. Development of a simulator for system reliability analysis. 3. Related researches for supporting the simulator : accelerated simulation analytic approach using PH-type distribution, analysis for dynamic repair effects. 154 refs., 5 tabs., 87 figs. (author)

  15. Subscales of the vestibular activities and participation questionnaire could be applied across cultures.

    Science.gov (United States)

    Mueller, Martin; Whitney, Susan L; Alghwiri, Alia; Alshebber, Kefah; Strobl, Ralf; Alghadir, Ahmad; Al-momani, Murad O; Furman, Joseph M; Grill, Eva

    2015-02-01

    The objective of this study was to assess the objectivity, cross-cultural validity, and convergent validity of the Vestibular Activities and Participation (VAP) questionnaire among four countries, Germany, United States, Jordan, and Saudi Arabia. This was a cross-sectional study conducted in four specialized outpatient dizziness clinics in Germany, United States, Jordan, and Saudi Arabia. A total of 453 participants were included in the study. The Rasch analysis revealed two separate subscales. Subscale 1 items included focusing attention, lying down, standing, bending, lifting and carrying objects, and sports. Subscale 2 items included walking long distances, climbing, running, moving around within buildings other than home, using transportation, and driving. The Pearson product-moment correlation between the Dizziness Handicap Inventory and the summary score of the VAP subscale 1 was 0.66 and was 0.64 for subscale 2. Owing to its shortness and intercultural adaptability, the new two-scale version of the VAP questionnaire lends itself to clinical practice and research across countries to estimate the effect of vertigo and dizziness on activity limitation and participation restrictions. Psychometrically sound summary scores can be calculated. More extended versions of the VAP can be used for comprehensive clinical assessment where summary scores are not needed or a more detailed documentation is warranted. Copyright © 2015 Elsevier Inc. All rights reserved.

  16. Evaluation of Neuropsychiatric Function in Phenylketonuria: Psychometric Properties of the ADHD Rating Scale-IV and Adult ADHD Self-Report Scale Inattention Subscale in Phenylketonuria.

    Science.gov (United States)

    Wyrwich, Kathleen W; Auguste, Priscilla; Yu, Ren; Zhang, Charlie; Dewees, Benjamin; Winslow, Barbara; Yu, Shui; Merilainen, Markus; Prasad, Suyash

    2015-06-01

    Previous qualitative research among adults and parents of children with phenylketonuria (PKU) has identified inattention as an important psychiatric aspect of this condition. The parent-reported ADHD Rating Scale-IV (ADHD RS-IV) and the Adult ADHD Self-Report Scale (ASRS) have been validated for measuring inattention symptoms in persons with attention-deficit/hyperactivity disorder (ADHD); however, their psychometric attributes for measuring PKU-related inattention have not been established. The primary objective of this investigation was to demonstrate the reliability, validity, and responsiveness of the ADHD RS-IV and ASRS inattention symptoms subscales in a randomized controlled trial of patients with PKU aged 8 years or older. A post hoc analysis investigated the psychometric properties (Rasch model fit, reliability, construct validity, and responsiveness) of the ADHD RS-IV and ASRS inattention subscales using data from a phase 3b, double-blind, placebo-controlled clinical trial in those with PKU aged 8 years or older. The Rasch results revealed good model fit, and reliability analyses revealed strong internal consistency reliability (α ≥ 0.87) and reproducibility (intraclass correlation coefficient ≥ 0.87) for both measures. Both inattention measures demonstrated the ability to discriminate between known groups (P < 0.001) created by the Clinical Global Impression-Severity scale. Correlations between the ADHD RS-IV and the ASRS with the Clinical Global Impression-Severity scale and the age-appropriate Behavior Rating Inventory of Executive Function Working Memory subscale were consistently moderate to strong (r ≥ 0.56). Similarly, results of the change score correlations were of moderate magnitude (r ≥ 0.43) for both measures when compared with changes over time in Behavior Rating Inventory of Executive Function Working Memory subscales. These findings of reliability, validity, and responsiveness of both the ADHD RS-IV and the ASRS inattention scales

  17. Reliability, validity and responsiveness of the Italian version of the Foot Function Index in patients with foot and ankle diseases.

    Science.gov (United States)

    Martinelli, Nicolò; Scotto, Gennaro Maria; Sartorelli, Elena; Bonifacini, Carlo; Bianchi, Alberto; Malerba, Francesco

    2014-02-01

    The purpose of this study was to translate the Foot Function Index (FFI) into Italian, to perform a cross-cultural adaptation and to evaluate the psychometric properties of the Italian version of FFI. The Italian FFI was developed according to the recommended forward/backward translation protocol and evaluated in patients with foot and ankle diseases. Feasibility, reliability [intraclass correlation coefficient (ICC)], internal consistency [Cronbach's alpha (CA)], construct validity (correlation with the SF-36 and a visual analogue scale (VAS) assessing for pain), responsiveness to surgery were assessed. The standardized effect size and standardized response mean were also evaluated. A total of 89 patients were recruited (mean age 51.8 ± 13.9 years, range 21-83). The Italian version of the FFI consisted in 18 items separated into a pain and disability subscales. CA value was 0.95 for both the subscales. The reproducibility was good with an ICC of 0.94 and 0.91 for pain and disability subscales, respectively. A strong correlation was found between the FFI and the scales of the SF-36 and the VAS with related content, particularly in the areas of physical function and pain was observed indicating good construct validity. After surgery, the mean FFI improved from 55.9 ± 24.8 to 32.4 ± 26.3 for the pain subscale and from 48.8 ± 28.8 to 24.9 ± 23.7 for the disability subscale (P validity and reliability of this score.

  18. Improvement of Matrix Converter Drive Reliability by Online Fault Detection and a Fault-Tolerant Switching Strategy

    DEFF Research Database (Denmark)

    Nguyen-Duy, Khiem; Liu, Tian-Hua; Chen, Der-Fa

    2011-01-01

    The matrix converter system is becoming a very promising candidate to replace the conventional two-stage ac/dc/ac converter, but system reliability remains an open issue. The most common reliability problem is that a bidirectional switch has an open-switch fault during operation. In this paper......, a matrix converter driving a speed-controlled permanent-magnet synchronous motor is examined under a single open-switch fault. First, a new fault-detection method is proposed using only the motor currents. Second, a novel fault-tolerant switching strategy is presented. By treating the matrix converter...... as a two-stage rectifier/inverter, existing modulation techniques for the inverter stage can be reused, whereas the rectifier stage is modified by control to counteract the fault. However, the proposed techniques require no additional hardware devices or circuit modifications to the matrix converter...

  19. Validation of the 4DSQ somatization subscale in the occupational health care setting as a screener.

    Science.gov (United States)

    de Vroege, Lars; Emons, Wilco H M; Sijtsma, Klaas; Hoedeman, Rob; van der Feltz-Cornelis, Christina M

    2015-03-01

    Somatoform disorders (physical symptoms without medical explanation that cause dysfunction) are prevalent in the occupational health (OH) care setting and are associated with functional impairment and absenteeism. Availability of psychometric instruments aimed at assessing somatoform disorders is limited. In the OH setting, so far only the Patient-Health-Questionnaire 15 has been validated as screener for somatoform disorder, and has been shown to have moderate validity. The Four-Dimensional Symptom Questionnaire (4DSQ) is frequently used in the OH setting but the Somatization subscale is not validated yet. The aim of this study is to validate the 4DSQ Somatization subscale as screener for DSM-IV somatoform disorder in the OH setting by using the MINI interview as gold standard. Employees absent from work due to physical symptoms, for a period longer than 6 weeks and shorter than 2 years, were asked to participate in this study. They filled out the 4DSQ and underwent a MINI interview by telephone for DSM-IV classification. Specificity and sensitivity scores were calculated for all possible cut-off scores and a receiver operator curve was computed for the Somatization subscale. 95 % confidence intervals (95 % CIs) were calculated for sensitivity and specificity. The Somatization subscale of the 4DSQ has an optimal cut point of 9, with specificity and sensitivity equal to 64.3 % [95 % CI (53.6; 73.7 %)] and 60.9 % [95 % CI (40.8; 77.8 %)], respectively. Receiver operator curves showed an area under the curve equal to 0.61 [SE = 0.07; 95 % CI (0.48; 0.75)] for the Somatization subscale of the 4DSQ. The 4DSQ Somatization subscale is a questionnaire of moderate sensitivity and specificity.

  20. Screening for Psychosocial Risk in Dutch Families of a Child With Cancer: Reliability, Validity, and Usability of the Psychosocial Assessment Tool.

    Science.gov (United States)

    Sint Nicolaas, Simone M; Schepers, Sasja A; Hoogerbrugge, Peter M; Caron, Huib N; Kaspers, Gertjan J L; van den Heuvel-Eibrink, Marry M; Grootenhuis, Martha A; Verhaak, Chris M

    2016-08-01

    The Psychosocial Assessment Tool (PAT) was developed to screen for psychosocial risk in families of a child diagnosed with cancer. The current study is the first describing the cross-cultural adaptation, reliability, validity, and usability of the PAT in an European country (Dutch translation). A total of 117 families (response rate 59%) of newly diagnosed children with cancer completed the PAT2.0 and validation measures. Acceptable reliability was obtained for the PAT total score (α = .72) and majority of subscales (0.50-0.82). Two subscales showed inadequate internal consistency (Social Support α = .19; Family Beliefs α = .20). Validity and usability were adequate. Of the families, 66% scored low (Universal), 29% medium (Targeted), and 5% high (Clinical) risk. This study confirms the cross-cultural applicability, reliability, and validity of the PAT total score. Reliability left room for improvement on subscale level. Future research should indicate whether the PAT can be used to provide cost-effective care. © The Author 2015. Published by Oxford University Press on behalf of the Society of Pediatric Psychology. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  1. Study on the improvement of the reliability of solar cells on polymer substrates; Etude et amelioration de la fiabilite des cellules solaires sur substrats polymeres

    Energy Technology Data Exchange (ETDEWEB)

    Fischer, D.; Ziegler, Y.; Closset, A.

    2004-07-01

    This final report for the Swiss Federal Office of Energy (SFOE) presents the results of work done on the improvement of the long-term reliability of flexible solar cells deposited on polyimide substrates. Several possibilities were explored simultaneously, including vacuum-de-gassing of the polyimide film, the prevention of water absorption by using diffusion barriers and the reduction of mechanical stress in the thin silicon layers. Work completed is described, including the adaptation of the deposition system, the structuring of metal coatings and improvements to existing equipment to reduce defects caused by dust. The continual effort being made to stabilise the production process and make it economically viable is noted.

  2. Towards parsimony in habit measurement: Testing the convergent and predictive validity of an automaticity subscale of the Self-Report Habit Index

    Science.gov (United States)

    2012-01-01

    Background The twelve-item Self-Report Habit Index (SRHI) is the most popular measure of energy-balance related habits. This measure characterises habit by automatic activation, behavioural frequency, and relevance to self-identity. Previous empirical research suggests that the SRHI may be abbreviated with no losses in reliability or predictive utility. Drawing on recent theorising suggesting that automaticity is the ‘active ingredient’ of habit-behaviour relationships, we tested whether an automaticity-specific SRHI subscale could capture habit-based behaviour patterns in self-report data. Methods A content validity task was undertaken to identify a subset of automaticity indicators within the SRHI. The reliability, convergent validity and predictive validity of the automaticity item subset was subsequently tested in secondary analyses of all previous SRHI applications, identified via systematic review, and in primary analyses of four raw datasets relating to energy‐balance relevant behaviours (inactive travel, active travel, snacking, and alcohol consumption). Results A four-item automaticity subscale (the ‘Self-Report Behavioural Automaticity Index’; ‘SRBAI’) was found to be reliable and sensitive to two hypothesised effects of habit on behaviour: a habit-behaviour correlation, and a moderating effect of habit on the intention-behaviour relationship. Conclusion The SRBAI offers a parsimonious measure that adequately captures habitual behaviour patterns. The SRBAI may be of particular utility in predicting future behaviour and in studies tracking habit formation or disruption. PMID:22935297

  3. Towards parsimony in habit measurement: testing the convergent and predictive validity of an automaticity subscale of the Self-Report Habit Index.

    Science.gov (United States)

    Gardner, Benjamin; Abraham, Charles; Lally, Phillippa; de Bruijn, Gert-Jan

    2012-08-30

    The twelve-item Self-Report Habit Index (SRHI) is the most popular measure of energy-balance related habits. This measure characterises habit by automatic activation, behavioural frequency, and relevance to self-identity. Previous empirical research suggests that the SRHI may be abbreviated with no losses in reliability or predictive utility. Drawing on recent theorising suggesting that automaticity is the 'active ingredient' of habit-behaviour relationships, we tested whether an automaticity-specific SRHI subscale could capture habit-based behaviour patterns in self-report data. A content validity task was undertaken to identify a subset of automaticity indicators within the SRHI. The reliability, convergent validity and predictive validity of the automaticity item subset was subsequently tested in secondary analyses of all previous SRHI applications, identified via systematic review, and in primary analyses of four raw datasets relating to energy-balance relevant behaviours (inactive travel, active travel, snacking, and alcohol consumption). A four-item automaticity subscale (the 'Self-Report Behavioural Automaticity Index'; 'SRBAI') was found to be reliable and sensitive to two hypothesised effects of habit on behaviour: a habit-behaviour correlation, and a moderating effect of habit on the intention-behaviour relationship. The SRBAI offers a parsimonious measure that adequately captures habitual behaviour patterns. The SRBAI may be of particular utility in predicting future behaviour and in studies tracking habit formation or disruption.

  4. Development of a Farsi translation of the AGREE instrument, and the effects of group discussion on improving the reliability of the scores.

    Science.gov (United States)

    Rashidian, Arash; Yousefi-Nooraie, Reza

    2012-06-01

    We aimed to develop a formal Farsi (Persian) translation of the Appraisal of Guidelines for Research and Evaluation (AGREE) clinical guideline appraisal instrument. We considered the effect of group discussion in improving the reliability of scores. We followed a multi-step process of translation including independent translations of the instrument and extensive assessment of face validity and fluency. We used the instruments to appraise 11 guidelines from three specialities. After the first appraisal, the raters discussed about each guideline in groups, and had the opportunity to revise their scores individually. In total 96 appraisals were conducted. The intra-class correlations (1,1) were calculated for domain scores obtained by two versions at each time point. We observed no statistically significant differences between the mean values obtained from the English and the translated versions of AGREE, and the scores at two time points. The average domain scores, as well as the reliability rose significantly after discussion. The Farsi version of the AGREE instrument yields in the scores comparable to the original version, despite a lower reliability. Revision of scores after group discussion leads to higher reliability, probably by helping the raters recognize what they might have overlooked during the short time of assessment. © 2011 Blackwell Publishing Ltd.

  5. Comparison of Child Behavior Checklist subscales in screening for obsessive-compulsive disorder

    DEFF Research Database (Denmark)

    Andersen, Pia Aaron Skovby; Bilenberg, Niels

    2012-01-01

    Obsessive-compulsive disorder (OCD) is a prevalent psychiatric disorder in children and adolescents associated with significant functional impairment. Early and correct diagnosis is essential for an optimal treatment outcome. The purpose of this study was to determine which of four subscales...... derived from the Child Behavior Checklist best discriminates OCD patients from clinical and population-based controls....

  6. Analysis of the Subscales of the Tennessee Self-Concept Scale.

    Science.gov (United States)

    Gellen, Murray I.; Hoffman, Roy A.

    1984-01-01

    Factor analyzed the item responses comprising each of the five external dimensions and the three internal dimensions of the Tennessee Self-Concept Scale. The results indicated that seven of the eight subscales are essentially single-factor scales. Implications for counseling are discussed. (Author)

  7. Evaluation of the Construction of the Subscales for the Piers-Harris and Tennessee Inventories.

    Science.gov (United States)

    Thomas, Julia Anne

    A sample of 234 fifth- and 259 sixth-grade students scaled the items of the Piers-Harris, Tennessee, Coopersmith, and Lipsett self-concept measures. The scaling of the Piers-Harris and the Tennessee inventories was examined in reference to their subscales. The present technique placed items on a bivariate plane of two orthogonal dimensions…

  8. MEMS reliability

    CERN Document Server

    Hartzell, Allyson L; Shea, Herbert R

    2010-01-01

    This book focuses on the reliability and manufacturability of MEMS at a fundamental level. It demonstrates how to design MEMs for reliability and provides detailed information on the different types of failure modes and how to avoid them.

  9. Improving the communication reliability of body sensor networks based on the IEEE 802.15.4 protocol.

    Science.gov (United States)

    Gomes, Diogo; Afonso, José A

    2014-03-01

    Body sensor networks (BSNs) enable continuous monitoring of patients anywhere, with minimum constraints to daily life activities. Although the IEEE 802.15.4 and ZigBee(®) (ZigBee Alliance, San Ramon, CA) standards were mainly developed for use in wireless sensors network (WSN) applications, they are also widely used in BSN applications because of device characteristics such as low power, low cost, and small form factor. However, compared with WSNs, BSNs present some very distinctive characteristics in terms of traffic and mobility patterns, heterogeneity of the nodes, and quality of service requirements. This article evaluates the suitability of the carrier sense multiple access-collision avoidance protocol, used by the IEEE 802.15.4 and ZigBee standards, for data-intensive BSN applications, through the execution of experimental tests in different evaluation scenarios, in order to take into account the effects of contention, clock drift, and hidden nodes on the communication reliability. Results show that the delivery ratio may decrease substantially during transitory periods, which can last for several minutes, to a minimum of 90% with retransmissions and 13% without retransmissions. This article also proposes and evaluates the performance of the BSN contention avoidance mechanism, which was designed to solve the identified reliability problems. This mechanism was able to restore the delivery ratio to 100% even in the scenario without retransmissions.

  10. Advanced computer technology - An aspect of the Terminal Configured Vehicle program. [air transportation capacity, productivity, all-weather reliability and noise reduction improvements

    Science.gov (United States)

    Berkstresser, B. K.

    1975-01-01

    NASA is conducting a Terminal Configured Vehicle program to provide improvements in the air transportation system such as increased system capacity and productivity, increased all-weather reliability, and reduced noise. A typical jet transport has been equipped with highly flexible digital display and automatic control equipment to study operational techniques for conventional takeoff and landing aircraft. The present airborne computer capability of this aircraft employs a multiple computer simple redundancy concept. The next step is to proceed from this concept to a reconfigurable computer system which can degrade gracefully in the event of a failure, adjust critical computations to remaining capacity, and reorder itself, in the case of transients, to the highest order of redundancy and reliability.

  11. 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

  12. USING A TOTAL QUALITY STRATEGY IN A NEW PRACTICAL APPROACH FOR IMPROVING THE PRODUCT RELIABILITY IN AUTOMOTIVE INDUSTRY

    National Research Council Canada - National Science Library

    Cristiano Fragassa; Ana Pavlovic; Salvatore Massimo

    2014-01-01

    In this paper a Total Quality Management strategy is proposed, refined and used with the aim at improving the quality of large-mass industrial products far beyond the technical specifications demanded...

  13. Clinical meaningfulness of Alzheimer's Disease Assessment Scale-Cognitive subscale change in relation to goal attainment in patients on cholinesterase inhibitors.

    Science.gov (United States)

    Rockwood, Kenneth; Howlett, Susan E; Hoffman, Deborah; Schindler, Rachel; Mitnitski, Arnold

    2017-10-01

    The clinical meaningfulness of Alzheimer's Disease Assessment Scale-Cognitive subscale (ADAS-Cog) subscale change is disputed. We compared 2- to 4-point ADAS-Cog changes with changes in Goal Attainment Scaling (GAS) and everyday function across initial ADAS-Cog scores and treatment responses. This exploratory analysis evaluated mild-moderate Alzheimer's disease patients treated with donepezil (12 months) or galantamine (8 months). Clinical meaningfulness was defined as concomitant ADAS-Cog and GAS changes of ±3 points and/or functional improvement. Patients with ≥3-point ADAS-Cog improvement significantly improved on GAS but not on standard tests of everyday function. ADAS-Cog "no change" (≤±3 points) was seen with mean GAS improvement. Initial ADAS-Cog improvement made endpoint improvement (ADAS-Cog 3 points and GAS 1 point) more likely (odds ratio = 6.9; 95% confidence interval = 2.5-19.5). In contrast, initial deterioration made endpoint improvement unlikely (0.33; 0.14-0.64). ADAS-Cog improvement and no change were each associated with GAS improvement. Initial ADAS-Cog worsening was unlikely to result in later improvement. ISRCTN26167328. Copyright © 2017. Published by Elsevier Inc.

  14. Spectral resolution in conjunction with polar plots improves the accuracy and reliability of FLIM measurements and estimates of FRET efficiency.

    Science.gov (United States)

    Chen, Y-C; Clegg, R M

    2011-10-01

    A spectrograph with continuous wavelength resolution has been integrated into a frequency-domain fluorescence lifetime-resolved imaging microscope (FLIM). The spectral information assists in the separation of multiple lifetime components, and helps resolve signal cross-talking that can interfere with an accurate analysis of multiple lifetime processes. This extends the number of different dyes that can be measured simultaneously in a FLIM measurement. Spectrally resolved FLIM (spectral-FLIM) also provides a means to measure more accurately the lifetime of a dim fluorescence component (as low as 2% of the total intensity) in the presence of another fluorescence component with a much higher intensity. A more reliable separation of the donor and acceptor fluorescence signals are possible for Förster resonance energy transfer (FRET) measurements; this allows more accurate determinations of both donor and acceptor lifetimes. By combining the polar plot analysis with spectral-FLIM data, the spectral dispersion of the acceptor signal can be used to derive the donor lifetime - and thereby the FRET efficiency - without iterative fitting. The lifetime relation between the donor and acceptor, in conjunction with spectral dispersion, is also used to separate the FRET pair signals from the donor alone signal. This method can be applied further to quantify the signals from separate FRET pairs, and provide information on the dynamics of the FRET pair between different states. © 2011 The Authors Journal of Microscopy © 2011 Royal Microscopical Society.

  15. Reliability Study of Solder Paste Alloy for the Improvement of Solder Joint at Surface Mount Fine-Pitch Components

    Directory of Open Access Journals (Sweden)

    Mohd Nizam Ab. Rahman

    2014-12-01

    Full Text Available The significant increase in metal costs has forced the electronics industry to provide new materials and methods to reduce costs, while maintaining customers’ high-quality expectations. This paper considers the problem of most electronic industries in reducing costly materials, by introducing a solder paste with alloy composition tin 98.3%, silver 0.3%, and copper 0.7%, used for the construction of the surface mount fine-pitch component on a Printing Wiring Board (PWB. The reliability of the solder joint between electronic components and PWB is evaluated through the dynamic characteristic test, thermal shock test, and Taguchi method after the printing process. After experimenting with the dynamic characteristic test and thermal shock test with 20 boards, the solder paste was still able to provide a high-quality solder joint. In particular, the Taguchi method is used to determine the optimal control parameters and noise factors of the Solder Printer (SP machine, that affects solder volume and solder height. The control parameters include table separation distance, squeegee speed, squeegee pressure, and table speed of the SP machine. The result shows that the most significant parameter for the solder volume is squeegee pressure (2.0 mm, and the solder height is the table speed of the SP machine (2.5 mm/s.

  16. Improved Efficiency and Reliability of NGS Amplicon Sequencing Data Analysis for Genetic Diagnostic Procedures Using AGSA Software

    Directory of Open Access Journals (Sweden)

    Axel Poulet

    2016-01-01

    Full Text Available Screening for BRCA mutations in women with familial risk of breast or ovarian cancer is an ideal situation for high-throughput sequencing, providing large amounts of low cost data. However, 454, Roche, and Ion Torrent, Thermo Fisher, technologies produce homopolymer-associated indel errors, complicating their use in routine diagnostics. We developed software, named AGSA, which helps to detect false positive mutations in homopolymeric sequences. Seventy-two familial breast cancer cases were analysed in parallel by amplicon 454 pyrosequencing and Sanger dideoxy sequencing for genetic variations of the BRCA genes. All 565 variants detected by dideoxy sequencing were also detected by pyrosequencing. Furthermore, pyrosequencing detected 42 variants that were missed with Sanger technique. Six amplicons contained homopolymer tracts in the coding sequence that were systematically misread by the software supplied by Roche. Read data plotted as histograms by AGSA software aided the analysis considerably and allowed validation of the majority of homopolymers. As an optimisation, additional 250 patients were analysed using microfluidic amplification of regions of interest (Access Array Fluidigm of the BRCA genes, followed by 454 sequencing and AGSA analysis. AGSA complements a complete line of high-throughput diagnostic sequence analysis, reducing time and costs while increasing reliability, notably for homopolymer tracts.

  17. Thermodynamic analysis and subscale modeling of space-based orbit transfer vehicle cryogenic propellant resupply

    Science.gov (United States)

    Defelice, David M.; Aydelott, John C.

    1987-01-01

    The resupply of the cryogenic propellants is an enabling technology for spacebased orbit transfer vehicles. As part of the NASA Lewis ongoing efforts in microgravity fluid management, thermodynamic analysis and subscale modeling techniques were developed to support an on-orbit test bed for cryogenic fluid management technologies. Analytical results have shown that subscale experimental modeling of liquid resupply can be used to validate analytical models when the appropriate target temperature is selected to relate the model to its prototype system. Further analyses were used to develop a thermodynamic model of the tank chilldown process which is required prior to the no-vent fill operation. These efforts were incorporated into two FORTRAN programs which were used to present preliminary analyticl results.

  18. 2017 NREL Photovoltaic Reliability Workshop

    Energy Technology Data Exchange (ETDEWEB)

    Kurtz, Sarah [National Renewable Energy Laboratory (NREL), Golden, CO (United States)

    2017-08-15

    NREL's Photovoltaic (PV) Reliability Workshop (PVRW) brings together PV reliability experts to share information, leading to the improvement of PV module reliability. Such improvement reduces the cost of solar electricity and promotes investor confidence in the technology -- both critical goals for moving PV technologies deeper into the electricity marketplace.

  19. Exploring measurement invariance by gender in the profile of mood states depression subscale among cancer survivors.

    Science.gov (United States)

    Kim, Jihye; Smith, Tenbroeck

    2017-01-01

    The Profile of Mood States-Short Form (POMS-SF) is a well-validated tool commonly used in medical/clinical research. Less attention has been paid to the measurement invariance of the POMS-the degree to which the structure and items behave similarly for different groups (e.g., women and men). This study investigated the measurement invariance of the POMS Depression subscale across gender groups in a sample of cancer survivors. The POMS Depression subscale has 8 items (Unhappy, Sad, Blue, Hopeless, Discouraged, Miserable, Helpless, and Worthless). Invariance was measured using multigroup confirmatory factor analysis. This study used data from American Cancer Society Studies of Cancer Survivors-II, a population-based survey of adult cancer survivors (n = 9170). We found factor structures and factor loadings were invariant for gender groups, but moderate differential item functioning (DIF) in the question containing the word blue. With regard to cancer survivors' gender, we found the Depression subscale of the POMS-SF had configural invariance, and partial metric and scalar invariance. This suggests that results should be interpreted with caution, especially when gender is considered important. More broadly, our finding suggests that questions with the word blue may introduce DIF into other measures of depressive mood. More research is needed to replicate these findings in other samples and with other instruments.

  20. Chilean experimental version of the State-Trait Depression Questionnaire (ST-DEP: Trait sub-scale (T-DEP

    Directory of Open Access Journals (Sweden)

    Pablo Vera-Villarroel

    2008-01-01

    Full Text Available This instrumental study presents the first validity and reliability data for the Trait subscale (T-DEP of the Chilean experimental version of the State and Trait Depression Inventory (ST-DEP: Euthymia and Dysthymia. The data were obtained from a sample of 300 university students. The internal consistency values for the TDEP were high (.90. The test-retest values from eight weeks time interval (fifty six days were elevated (.78. A factorial analysis of the principal components revealed a principal factor for all of the constructed items in this experimental version of the TDEP. The last, promax rotation showed two clear main factors similar in size: negative affectivity (Dysthymia and positive affectivity (Euthymia. The convergent validity indexes for the Beck Depression Inventory and the Zung Self Rating Depression Scale, were also high, with indexes ranging from .64 to .71. The correlation between State- Trait Anxiety Inventory and the depression scales used in this study was high (between .63 and .78, once again indicating the usual overlapping between anxiety and depression seen in most depression inventories.

  1. Grid reliability

    CERN Document Server

    Saiz, P; Rocha, R; Andreeva, J

    2007-01-01

    We are offering a system to track the efficiency of different components of the GRID. We can study the performance of both the WMS and the data transfers At the moment, we have set different parts of the system for ALICE, ATLAS, CMS and LHCb. None of the components that we have developed are VO specific, therefore it would be very easy to deploy them for any other VO. Our main goal is basically to improve the reliability of the GRID. The main idea is to discover as soon as possible the different problems that have happened, and inform the responsible. Since we study the jobs and transfers issued by real users, we see the same problems that users see. As a matter of fact, we see even more problems than the end user does, since we are also interested in following up the errors that GRID components can overcome by themselves (like for instance, in case of a job failure, resubmitting the job to a different site). This kind of information is very useful to site and VO administrators. They can find out the efficien...

  2. Improving medical diagnosis reliability using Boosted C5.0 decision tree empowered by Particle Swarm Optimization.

    Science.gov (United States)

    Pashaei, Elnaz; Ozen, Mustafa; Aydin, Nizamettin

    2015-08-01

    Improving accuracy of supervised classification algorithms in biomedical applications is one of active area of research. In this study, we improve the performance of Particle Swarm Optimization (PSO) combined with C4.5 decision tree (PSO+C4.5) classifier by applying Boosted C5.0 decision tree as the fitness function. To evaluate the effectiveness of our proposed method, it is implemented on 1 microarray dataset and 5 different medical data sets obtained from UCI machine learning databases. Moreover, the results of PSO + Boosted C5.0 implementation are compared to eight well-known benchmark classification methods (PSO+C4.5, support vector machine under the kernel of Radial Basis Function, Classification And Regression Tree (CART), C4.5 decision tree, C5.0 decision tree, Boosted C5.0 decision tree, Naive Bayes and Weighted K-Nearest neighbor). Repeated five-fold cross-validation method was used to justify the performance of classifiers. Experimental results show that our proposed method not only improve the performance of PSO+C4.5 but also obtains higher classification accuracy compared to the other classification methods.

  3. Online signal processing of internal anal sphincter activity during pelvic autonomic nerve stimulation: a new method to improve the reliability of intra-operative neuromonitoring signals.

    Science.gov (United States)

    Kauff, D W; Koch, K P; Somerlik, K H; Heimann, A; Hoffmann, K P; Lang, H; Kneist, W

    2011-12-01

    Intra-operative neuromonitoring is increasingly applied in several surgical disciplines and has been introduced to facilitate pelvic autonomic nerve preservation. Nevertheless, it has been considered a questionable tool for the minimization of risk, as the results are variable and might be misleading. The aim of the present experimental study was to develop an intra-operative neuromonitoring system with improved reliability for monitoring pelvic autonomic nerve function. Fifteen pigs underwent low anterior rectal resection with pelvic autonomic nerve preservation. Intra-operative neuromonitoring was performed under autonomic nerve stimulation with observation of electromyographic signals of the internal anal sphincter and bladder manometry. As the internal anal sphincter frequency spectrum during stimulation was found to be mainly in the range of 5-20 Hz, intra-operative neuromonitoring signals were postoperatively processed by implementation of matching band pass filters. In 10 preliminary experiments, signal processing was performed offline in the postoperative analysis. Of 163 stimulations intra-operatively assessed by the surgeon as positive responses, 135 (83%) were confirmed after signal processing. In the following five consecutive experiments intra-operative online signal processing was realized and demonstrated reliable intra-operative neuromonitoring signals of internal anal sphincter activity with significant increase during pelvic autonomic nerve stimulation [0.5 μV (interquartile range = 0.3-0.7) vs 4.8 μV (interquartile range = 2.5-7.5); P < 0.001]. Online signal processing of internal anal sphincter activity aids reliable identification of pelvic autonomic nerves with potential for improvement of intra-operative neuromonitoring in pelvic surgery. © 2011 The Authors. Colorectal Disease © 2011 The Association of Coloproctology of Great Britain and Ireland.

  4. Journey Toward High Reliability: A Comprehensive Safety Program to Improve Quality of Care and Safety Culture in a Large, Multisite Radiation Oncology Department.

    Science.gov (United States)

    Woodhouse, Kristina Demas; Volz, Edna; Maity, Amit; Gabriel, Peter E; Solberg, Timothy D; Bergendahl, Howard W; Hahn, Stephen M

    2016-05-01

    High-reliability organizations (HROs) focus on continuous identification and improvement of safety issues. We sought to advance a large, multisite radiation oncology department toward high reliability through the implementation of a comprehensive safety culture (SC) program at the University of Pennsylvania Department of Radiation Oncology. In 2011, with guidance from safety literature and experts in HROs, we designed an SC framework to reduce radiation errors. All state-reported medical events (SRMEs) from 2009 to 2016 were retrospectively reviewed and plotted on a control chart. Changes in SC grade were assessed using the Agency for Healthcare Research and Quality Hospital Survey. Outcomes measured included the number of radiation treatment fractions and days between SRMEs, as well as SC grade. Multifaceted safety initiatives were implemented at our main academic center and across all network sites. Postintervention results demonstrate increased staff fundamental safety knowledge, enhanced peer review with an electronic system, and special cause variation of SRMEs on control chart analysis. From 2009 to 2016, the number of days and fractions between SRMEs significantly increased, from a mean of 174 to 541 days (P patient SC grade over time. Our journey toward becoming an HRO has led to the development of a robust SC through a comprehensive safety framework. Our multifaceted initiatives, focusing on culture and system changes, can be successfully implemented in a large academic radiation oncology department to yield measurable improvements in SC and outcomes. Copyright © 2016 by American Society of Clinical Oncology.

  5. An improved behavioural assay demonstrates that ultrasound vocalizations constitute a reliable indicator of chronic cancer pain and neuropathic pain

    Directory of Open Access Journals (Sweden)

    Selvaraj Deepitha

    2010-03-01

    Full Text Available Abstract Background On-going pain is one of the most debilitating symptoms associated with a variety of chronic pain disorders. An understanding of mechanisms underlying on-going pain, i.e. stimulus-independent pain has been hampered so far by a lack of behavioural parameters which enable studying it in experimental animals. Ultrasound vocalizations (USVs have been proposed to correlate with pain evoked by an acute activation of nociceptors. However, literature on the utility of USVs as an indicator of chronic pain is very controversial. A majority of these inconsistencies arise from parameters confounding behavioural experiments, which include novelty, fear and stress due to restrain, amongst others. Results We have developed an improved assay which overcomes these confounding factors and enables studying USVs in freely moving mice repetitively over several weeks. Using this improved assay, we report here that USVs increase significantly in mice with bone metastases-induced cancer pain or neuropathic pain for several weeks, in comparison to sham-treated mice. Importantly, analgesic drugs which are known to alleviate tumour pain or neuropathic pain in human patients significantly reduce USVs as well as mechanical allodynia in corresponding mouse models. Conclusions We show that studying USVs and mechanical allodynia in the same cohort of mice enables comparing the temporal progression of on-going pain (i.e. stimulus-independent pain and stimulus-evoked pain in these clinically highly-relevant forms of chronic pain.

  6. Reliability Engineering

    CERN Document Server

    Lazzaroni, Massimo

    2012-01-01

    This book gives a practical guide for designers and users in Information and Communication Technology context. In particular, in the first Section, the definition of the fundamental terms according to the international standards are given. Then, some theoretical concepts and reliability models are presented in Chapters 2 and 3: the aim is to evaluate performance for components and systems and reliability growth. Chapter 4, by introducing the laboratory tests, puts in evidence the reliability concept from the experimental point of view. In ICT context, the failure rate for a given system can be

  7. Application of a force sensor to improve the reliability of measurement with Articulated Arm Coordinate Measuring Machines.

    Science.gov (United States)

    González-Madruga, Daniel; Cuesta González, Eduardo; Barreiro García, Joaquín; Fernandez-Abia, Ana Isabel

    2013-08-13

    A study of the operator contact force influence on the performance of Articulated Arm Coordinate Measuring Machines (AACMMs) is presented in this paper. After developing a sensor capable of measuring the contact force applied by an operator, a ring gauge has been used to analyse the relationship between the contact force and diameter and form errors measured with the AACMM. As a result, contact force has been proved as one of the main factors influencing the AACMM performance. A probe deflection model based on the Finite Element Method (FEM) has been also proposed in order to obtain the AACMM probe deflection caused by contact force. This allows measurement correction by comparing them with reference values, specifically, a ring gauge. Experimental test results show a significant measurement improvement that minimizes diameter error. Finally, an uncertainty evaluation for the contact force sensor and AACMM measurements with and without probe deflection model has been carried out in order to validate the ability of the sensor and the methodology followed.

  8. Application of a Force Sensor to Improve the Reliability of Measurement with Articulated Arm Coordinate Measuring Machines

    Directory of Open Access Journals (Sweden)

    Joaquín Barreiro

    2013-08-01

    Full Text Available A study of the operator contact force influence on the performance of Articulated Arm Coordinate Measuring Machines (AACMMs is presented in this paper. After developing a sensor capable of measuring the contact force applied by an operator, a ring gauge has been used to analyse the relationship between the contact force and diameter and form errors measured with the AACMM. As a result, contact force has been proved as one of the main factors influencing the AACMM performance. A probe deflection model based on the Finite Element Method (FEM has been also proposed in order to obtain the AACMM probe deflection caused by contact force. This allows measurement correction by comparing them with reference values, specifically, a ring gauge. Experimental test results show a significant measurement improvement that minimizes diameter error. Finally, an uncertainty evaluation for the contact force sensor and AACMM measurements with and without probe deflection model has been carried out in order to validate the ability of the sensor and the methodology followed.

  9. Can we improve accuracy and reliability of MRI interpretation in children with optic pathway glioma? Proposal for a reproducible imaging classification

    Energy Technology Data Exchange (ETDEWEB)

    Lambron, Julien; Frampas, Eric; Toulgoat, Frederique [University Hospital, Department of Radiology, Nantes (France); Rakotonjanahary, Josue [University Hospital, Department of Pediatric Oncology, Angers (France); University Paris Diderot, INSERM CIE5 Robert Debre Hospital, Assistance Publique-Hopitaux de Paris (AP-HP), Paris (France); Loisel, Didier [University Hospital, Department of Radiology, Angers (France); Carli, Emilie de; Rialland, Xavier [University Hospital, Department of Pediatric Oncology, Angers (France); Delion, Matthieu [University Hospital, Department of Neurosurgery, Angers (France)

    2016-02-15

    Magnetic resonance (MR) images from children with optic pathway glioma (OPG) are complex. We initiated this study to evaluate the accuracy of MR imaging (MRI) interpretation and to propose a simple and reproducible imaging classification for MRI. We randomly selected 140 MRIs from among 510 MRIs performed on 104 children diagnosed with OPG in France from 1990 to 2004. These images were reviewed independently by three radiologists (F.T., 15 years of experience in neuroradiology; D.L., 25 years of experience in pediatric radiology; and J.L., 3 years of experience in radiology) using a classification derived from the Dodge and modified Dodge classifications. Intra- and interobserver reliabilities were assessed using the Bland-Altman method and the kappa coefficient. These reviews allowed the definition of reliable criteria for MRI interpretation. The reviews showed intraobserver variability and large discrepancies among the three radiologists (kappa coefficient varying from 0.11 to 1). These variabilities were too large for the interpretation to be considered reproducible over time or among observers. A consensual analysis, taking into account all observed variabilities, allowed the development of a definitive interpretation protocol. Using this revised protocol, we observed consistent intra- and interobserver results (kappa coefficient varying from 0.56 to 1). The mean interobserver difference for the solid portion of the tumor with contrast enhancement was 0.8 cm{sup 3} (limits of agreement = -16 to 17). We propose simple and precise rules for improving the accuracy and reliability of MRI interpretation for children with OPG. Further studies will be necessary to investigate the possible prognostic value of this approach. (orig.)

  10. Development of improved processing and evaluation methods for high reliability structural ceramics for advanced heat engine applications Phase II. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Pujari, V.J.; Tracey, D.M.; Foley, M.R. [and others

    1996-02-01

    The research program had as goals the development and demonstration of significant improvements in processing methods, process controls, and nondestructive evaluation (NDE) which can be commercially implemented to produce high reliability silicon nitride components for advanced heat engine applications at temperatures to 1370{degrees}C. In Phase I of the program a process was developed that resulted in a silicon nitride - 4 w% yttria HIP`ed material (NCX 5102) that displayed unprecedented strength and reliability. An average tensile strength of 1 GPa and a strength distribution following a 3-parameter Weibull distribution were demonstrated by testing several hundred buttonhead tensile specimens. The Phase II program focused on the development of methodology for colloidal consolidation producing green microstructure which minimizes downstream process problems such as drying, shrinkage, cracking, and part distortion during densification. Furthermore, the program focused on the extension of the process to gas pressure sinterable (GPS) compositions. Excellent results were obtained for the HIP composition processed for minimal density gradients, both with respect to room-temperature strength and high-temperature creep resistance. Complex component fabricability of this material was demonstrated by producing engine-vane prototypes. Strength data for the GPS material (NCX-5400) suggest that it ranks very high relative to other silicon nitride materials in terms of tensile/flexure strength ratio, a measure of volume quality. This high quality was derived from the closed-loop colloidal process employed in the program.

  11. Improving the Reliability of Student Scores from Speeded Assessments: An Illustration of Conditional Item Response Theory Using a Computer-Administered Measure of Vocabulary.

    Science.gov (United States)

    Petscher, Yaacov; Mitchell, Alison M; Foorman, Barbara R

    2015-01-01

    A growing body of literature suggests that response latency, the amount of time it takes an individual to respond to an item, may be an important factor to consider when using assessment data to estimate the ability of an individual. Considering that tests of passage and list fluency are being adapted to a computer administration format, it is possible that accounting for individual differences in response times may be an increasingly feasible option to strengthen the precision of individual scores. The present research evaluated the differential reliability of scores when using classical test theory and item response theory as compared to a conditional item response model which includes response time as an item parameter. Results indicated that the precision of student ability scores increased by an average of 5 % when using the conditional item response model, with greater improvements for those who were average or high ability. Implications for measurement models of speeded assessments are discussed.

  12. Changes to the subscales of two vision-related quality of life questionnaires are proposed.

    Science.gov (United States)

    de Boer, Michiel R; de Vet, Henrica C W; Terwee, Caroline B; Moll, Annette C; Völker-Dieben, Hennie J M; van Rens, Ger H M B

    2005-12-01

    Psychometrically sound questionnaires for the assessment of vision-related quality of life (QOL) are scarce. Therefore, the objective was to further validate two vision-related QOL questionnaires in a Dutch population of visually impaired elderly. A total of 329 visually impaired older persons referred to low vision services completed the low vision QOL (LVQOL) and Vision-Related Quality of Life Core Measure (VCM1) questionnaires at baseline, after 1-4 weeks (retest), and after 5 months. Confirmatory factor analyses were performed on baseline data. The smallest detectable change (SDC) was assessed, based on the standard error of measurement (SEM). Change scores between the baseline and 5 months follow-up data were related to a general transition question to assess the minimal important change (MIC). Furthermore, the MIC was related to the SDC, to examine whether the MICs were detectable beyond measurement error. The original factor structures could not be confirmed. After omitting items and remodeling, adequate fits were obtained. SDCs comprised at least one quarter of the scale for all scales and subscales on the individual level and exceeded the MICs on every occasion. We propose MICs of 5-10 points for the scales and subscales of the LVQOL and VCM1. The questionnaires are not useful in the follow-up of individual patients.

  13. Practical Application of a Subscale Transport Aircraft for Flight Research in Control Upset and Failure Conditions

    Science.gov (United States)

    Cunningham, Kevin; Foster, John V.; Morelli, Eugene A.; Murch, Austin M.

    2008-01-01

    Over the past decade, the goal of reducing the fatal accident rate of large transport aircraft has resulted in research aimed at the problem of aircraft loss-of-control. Starting in 1999, the NASA Aviation Safety Program initiated research that included vehicle dynamics modeling, system health monitoring, and reconfigurable control systems focused on flight regimes beyond the normal flight envelope. In recent years, there has been an increased emphasis on adaptive control technologies for recovery from control upsets or failures including damage scenarios. As part of these efforts, NASA has developed the Airborne Subscale Transport Aircraft Research (AirSTAR) flight facility to allow flight research and validation, and system testing for flight regimes that are considered too risky for full-scale manned transport airplane testing. The AirSTAR facility utilizes dynamically-scaled vehicles that enable the application of subscale flight test results to full scale vehicles. This paper describes the modeling and simulation approach used for AirSTAR vehicles that supports the goals of efficient, low-cost and safe flight research in abnormal flight conditions. Modeling of aerodynamics, controls, and propulsion will be discussed as well as the application of simulation to flight control system development, test planning, risk mitigation, and flight research.

  14. Topographic effect of Sub-scale Mountains around the main Tibetan Plateau on Asian climate

    Science.gov (United States)

    Sha, Yingying; Shi, Zhengguo

    2017-04-01

    As one of the most important tectonic events in Cenozoic, the uplift of the Tibetan Plateau (TP) is considered to have profound influences on the evolution of Asian climate.However, the potential influence from the sub-scale mountains around the main TP is largely neglected. In actual, these sub-scale mountains may affect some climate systems, which facilitates from their sensitive locations. Taking the Mongolian Plateau (MP) and Yunnan-Guizhou Plateau (YGP, SW China) as examples, they are located at the core paths of mid-latitude winter westerly and Indian summer southwesterly monsoon, respectively, and seem to significantly block the eastward propagation of these systems from modern climatological data. In this study, general circulation model experiments with and without mountains are employed to evaluate the topographic effect of MP and YGP on the Asian climate. The results show that, the MP, despite its smaller size, exerts a great influence on the strengthened winter climate over East Asia, including the East Asian trough, the subtropical westerly jet and the winter monsoon. The YGP, however, plays an opposite role in the Indian monsoon change, compared to the main TP. It weakens the Indian summer monsoon circulation and associated precipitation. Thus, the response of Asian climate to the mountain uplift depends closely on the actual distributions of topography rather than a simplified bulk of main TP.

  15. Adverse learning strategy: the Adelaide Diagnostic Learning Inventory and its subscale replicability in a medical student population.

    Science.gov (United States)

    Welch, G; Pearce, K; Lewis, M; Mellsop, G

    1990-03-01

    The Adelaide Diagnostic Learning Inventory (ADLIMS) is a measure of learning styles and learning pathologies that was designed to investigate the impact of traditional approaches to learning versus problem-based learning and to identify students whose approach to learning tasks predicted poor academic performance. In this study, some important psychometric properties of the ADLIMS were examined, including its factor structure. In this study, factor replicability across samples was argued to provide a more robust and psychologically meaningful factor solution than that which can be obtained using traditional mathematical criteria. The results of the factor analysis did not confirm the presence of the four factor solution earlier reported for the ADLIMS, but did identify three clear factors that had very high replicability. An inspection of the items comprising these three factors showed that factor 1 tapped subjective distress related to poor study habits, lack of motivation to study, and distraction from social activities. Factor 2 tapped distress arising from high achievement expectations that were hampered by superficial or disorganized study habits that did not enable the student to grasp the relationships between concepts and ideas. Factor 3 tapped positive feelings and a sense of satisfaction associated with a problem-based approach to the learning of new study material. Although the internal reliability of the ADLIMS subscales met the requirements of a measure to be used in general research such as in the investigation of correlates among groups of medical students, they did not meet the higher requirements of a measure to be used to identify or predict individuals with pathological learning styles.

  16. Reliability and Factorial Validity of the Artes de Lenguaje.

    Science.gov (United States)

    Powers, Stephen; And Others

    1984-01-01

    Spanish speaking first graders were administered the Artes de Lenguage (ADL)--a Spanish, criterion-referenced, language arts test. Reliability analyses indicated the adequacy of three of the four subscales (Phonetic Analysis, Vocabulary Development, Comprehension Skills, and General Skills). A principal factors analysis of the intercorrelation…

  17. The Brief Aggression Questionnaire: Structure, Validity, Reliability, and Generalizability.

    Science.gov (United States)

    Webster, Gregory D; DeWall, C Nathan; Pond, Richard S; Deckman, Timothy; Jonason, Peter K; Le, Bonnie M; Nichols, Austin Lee; Schember, Tatiana Orozco; Crysel, Laura C; Crosier, Benjamin S; Smith, C Veronica; Paddock, E Layne; Nezlek, John B; Kirkpatrick, Lee A; Bryan, Angela D; Bator, Renée J

    2015-01-01

    In contexts that increasingly demand brief self-report measures (e.g., experience sampling, longitudinal and field studies), researchers seek succinct surveys that maintain reliability and validity. One such measure is the 12-item Brief Aggression Questionnaire (BAQ; Webster et al., 2014), which uses 4 3-item subscales: Physical Aggression, Verbal Aggression, Anger, and Hostility. Although prior work suggests the BAQ's scores are reliable and valid, we addressed some lingering concerns. Across 3 studies (N = 1,279), we found that the BAQ had a 4-factor structure, possessed long-term test-retest reliability across 12 weeks, predicted differences in behavioral aggression over time in a laboratory experiment, generalized to a diverse nonstudent sample, and showed convergent validity with a displaced aggression measure. In addition, the BAQ's 3-item Anger subscale showed convergent validity with a trait anger measure. We discuss the BAQ's potential reliability, validity, limitations, and uses as an efficient measure of aggressive traits.

  18. Development of a reliable, valid measure to assess parents' and teachers' understanding of postural care for children with physical disabilities: the (UKC PostCarD) questionnaire.

    Science.gov (United States)

    Hotham, S; Hutton, E; Hamilton-West, K E

    2015-11-01

    Previous research has highlighted lack of knowledge, understanding and confidence among parents and teachers responsible for the postural care of children with physical disability. Interventions designed to improve these qualities require a reliable and validated tool to assess pre- and post-intervention levels. Currently, however, no validated measure of postural care confidence (i.e. self-efficacy) exists. Hence, the aim of this research was to develop a reliable and valid questionnaire to assess parents' and teachers' confidence, alongside knowledge and understanding of postural care - the Understanding Knowledge and Confidence in providing POSTural CARe for children with Disabilities (UKC PostCarD) questionnaire. Items were developed by a multidisciplinary team and designed to map onto the content of 'An A-to-Z of Postural Care'. Parents, teachers and therapists assessed items for face validity. Scale reliability was then assessed using Cronbach's alpha and known-group validity was assessed by comparing scores of an 'expert' group (physiotherapists and occupational therapists) with those of a 'non-expert' group (with no formal training in postural care). The total scale and all three subscales (understanding and knowledge, confidence and concerns) demonstrated adequate reliability (α > 0.83) and subscale correlations formed a logical pattern (understanding and knowledge correlated positively with confidence and negatively with concerns). Experts' (n = 111) scores were higher than non-experts' (n = 79) for the total scale and all subscales (P < 0.001). Findings support the reliability and validity of the UKC PostCarD questionnaire as a measure of understanding, knowledge and confidence in providing postural care for children with disabilities. © 2015 John Wiley & Sons Ltd.

  19. Improving the performance and reliability of inverted planar perovskite solar cells with a carbon nanotubes/PEDOT:PSS hybrid hole collector.

    Science.gov (United States)

    Yoon, Saemon; Ha, Tae-Jun; Kang, Dong-Won

    2017-07-13

    Adopting an efficient charge transport layer is crucial to improve the photovoltaic (PV) performances of organo-lead halide perovskite (PRV) solar cells. In this study, we suggest a novel hybrid hole-transport layer (HTL) consisting of single-walled carbon nanotubes (SWNTs) and poly(3,4-ethylenedioxythiophene) polystyrene sulfonate (PEDOT:PSS) for inverted-planar PRV devices. The SWNTs were drop-cast on ITO/glass substrates, and they were partly grown perpendicular to the substrates. Then, we coated PEDOT:PSS to cover the SWNTs for complete electron-blocking. A PRV light-harvester was spin-cast on the hybrid HTL, and the vertical SWNTs protruded into the PRV through penetrating the PEDOT:PSS. Steady-state photoluminescence spectroscopy evidenced that the SWNTs/PEDOT:PSS hybrid HTL showed enhanced charge-carrier quenching properties. The hybrid HTL also revealed negligible parasitic absorption loss checked by UV-Vis spectroscopy. These contributed to improve the average power conversion efficiency from 9.4% to 11.0% (up to 12.5% for the best cell) based on fabricated 90 devices. Furthermore, significant suppression of current-voltage hysteresis was attained by employing the hybrid HTL. This study not only manifests unprecedented utilization of the SWNTs for the HTL in inverted planar PRV cells but also paves the way for the development of high-performance and reliable PRV solar cells compatible with flexible processing at low temperature (<150 °C).

  20. Change of International Restless Legs Syndrome Study Group Rating Scale subscales with treatment and placebo: a pilot study

    Directory of Open Access Journals (Sweden)

    Mitchell UH

    2014-02-01

    Full Text Available Ulrike H Mitchell,1 Sterling C Hilton2 1Brigham Young University, Department of Exercise Sciences, 2Department of Educational Leadership and Foundations, Provo, UT, USA Background: In 2003, the 10-question International Restless Legs Syndrome Study Group Rating Scale (IRLS was developed as a means of assessing the severity of restless legs syndrome. Two subscales were identified: symptom severity (SS 1 and symptom impact (SS 2. Only one study has investigated the subscales' responsiveness to a 12-week treatment with ropinirole. This current study was undertaken to assess the impact of a 4-week, non-pharmaceutical treatment on the two subscales and to explore whether or not both subscales were impacted by the observed placebo effect. Methods: The pooled data from questionnaires of 58 patients (41 from both treatment groups and 17 from the sham treatment control group, who participated in two clinical studies, were reviewed. Their change in score over a 4-week trial was computed. The average change in both subscales in both groups was computed and t-tests were performed. Results: In the treatment group, the average scores of both subscales changed significantly from baseline to week 4 (P<0.005 for both. Compared to the control, SS 1 changed (P<0.001, but not SS 2 (P=0.18. In the sham treatment group, the scores for SS 1 changed significantly (P=0.002, but not for SS 2 (P=0.2. Conclusion: This study corroborated findings from an earlier study in which both subscales changed with a 12-week drug treatment. It also showed that the observed placebo effect is attributed to a small but significant change in symptom severity, but not symptom impact. Keywords: restless legs syndrome, RLS severity scale, IRLS subscales, symptom impact, symptom severity

  1. Comparative Responsiveness of the PROMIS Pain Interference Short Forms, Brief Pain Inventory, PEG, and SF-36 Bodily Pain Subscale.

    Science.gov (United States)

    Kean, Jacob; Monahan, Patrick O; Kroenke, Kurt; Wu, Jingwei; Yu, Zhangsheng; Stump, Tim E; Krebs, Erin E

    2016-04-01

    To compare the sensitivity to change and the responsiveness to intervention of the PROMIS Pain Interference short forms, Brief Pain Inventory (BPI), 3-item PEG scale, and SF-36 Bodily Pain subscale in a sample of patients with persistent musculoskeletal pain of moderate severity. Standardized response means, standardized effect sizes, and receiver operating curve analyses were used to assess change between baseline and 3-month assessments in 250 participants who participated in a randomized clinical effectiveness trial of collaborative telecare management for moderate to severe and persistent musculoskeletal pain. The BPI, PEG, and SF-36 Bodily Pain measures were more sensitive to patient-reported global change than the PROMIS Pain Interference short forms, especially for the clinically improved group, for which the change detected by the PROMIS short forms was not statistically significant. The BPI was more responsive to the clinical intervention than the SF-36 Bodily Pain and PROMIS Pain Interference measures. Post hoc analyses exploring these findings did not suggest that differences in content or rating scale structure (number of response options or anchoring language) adequately explained the observed differences in the detection of change. In this clinical trial, the BPI and PEG measures were better able to detect change than the SF-36 Bodily Pain and PROMIS Pain Interference measures.

  2. Stability of memories of parental rearing among psychiatric inpatients: a replication based on EMBU subscales.

    Science.gov (United States)

    Richter, J; Eisemann, M

    2001-01-01

    With regard to information about parental rearing, retrospective data are exclusively available among adults. These data are vulnerable due to various biases. This study was performed in order to replicate the findings of overall stability of three perceived parental rearing factors of the EMBU (Swedish acronym for 'own memories of childhood upbringing') based on 14 rather detailed subscales. A consecutive sample of 220 depressive inpatients were investigated on admission and at discharge by means of the EMBU, the Beck Depression Inventory and the Dysfunctional Attitude Scale. Perceived parental rearing scores showed high stability despite clinically significant changes in the severity of depression, except for 'tolerance', 'guilt engendering', 'performance orientation' and 'shaming' parenting with probable gender-specific effects which were found to covary with dysfunctional attitudes. Recall of parenting should be taken as a subjective truth when it is assessed by standardised behaviour-oriented questionnaires like the EMBU. Copyright 2002 S. Karger AG, Basel

  3. Anxiety Sensitivity Index (ASI-3) subscales predict unique variance in anxiety and depressive symptoms.

    Science.gov (United States)

    Olthuis, Janine V; Watt, Margo C; Stewart, Sherry H

    2014-03-01

    Anxiety sensitivity (AS) has been implicated in the development and maintenance of a range of mental health problems. The development of the Anxiety Sensitivity Index - 3, a psychometrically sound index of AS, has provided the opportunity to better understand how the lower-order factors of AS - physical, psychological, and social concerns - are associated with unique forms of psychopathology. The present study investigated these associations among 85 treatment-seeking adults with high AS. Participants completed measures of AS, anxiety, and depression. Multiple regression analyses controlling for other emotional disorder symptoms revealed unique associations between AS subscales and certain types of psychopathology. Only physical concerns predicted unique variance in panic, only cognitive concerns predicted unique variance in depressive symptoms, and social anxiety was predicted by only social concerns. Findings emphasize the importance of considering the multidimensional nature of AS in understanding its role in anxiety and depression and their treatment. Copyright © 2013 Elsevier Ltd. All rights reserved.

  4. Subscale Validation of the Subsurface Active Filtration of Exhaust (SAFE) Approach to the NTP Ground Testing

    Science.gov (United States)

    Marshall, William M.; Borowski, Stanley K.; Bulman, Mel; Joyner, Russell; Martin, Charles R.

    2015-01-01

    Nuclear thermal propulsion (NTP) has been recognized as an enabling technology for missions to Mars and beyond. However, one of the key challenges of developing a nuclear thermal rocket is conducting verification and development tests on the ground. A number of ground test options are presented, with the Sub-surface Active Filtration of Exhaust (SAFE) method identified as a preferred path forward for the NTP program. The SAFE concept utilizes the natural soil characteristics present at the Nevada National Security Site to provide a natural filter for nuclear rocket exhaust during ground testing. A validation method of the SAFE concept is presented, utilizing a non-nuclear sub-scale hydrogen/oxygen rocket seeded with detectible radioisotopes. Additionally, some alternative ground test concepts, based upon the SAFE concept, are presented. Finally, an overview of the ongoing discussions of developing a ground test campaign are presented.

  5. A psychometric evaluation of the Diabetes Symptom Checklist-Revised (DSC-R cognitive distress, fatigue, hyperglycemia, and hypoglycemia subscales in patients with type 1 and type 2 diabetes

    Directory of Open Access Journals (Sweden)

    April N Naegeli

    2010-03-01

    Full Text Available April N Naegeli1, Timothy E Stump2, Risa P Hayes11Global Health Outcomes, Eli Lilly and Company, Indianapolis, IN, USA; 2Consultant, Indianapolis, IN, USAObjective: To explore the use of Diabetes Symptom Checklist-Revised (DSC-R Cognitive Distress, Fatigue, Hyperglycemia, and Hypoglycemia subscales as measures of acute diabetesassociated symptoms in patients with both type 1 and 2 diabetes.Research design and methods: Our study was conducted in context of two international, multicenter, randomized clinical trials for inhaled insulin. Confirmatory factor analyses and assessments of reliability and construct validity were performed.Results: Study participants were 371 patients with type 2 (56% male; mean age, 57 years and 481 with type 1 diabetes (57% male, mean age, 40 years. In both populations a four-factor model was the best fit. Cronbach’s α ≥ 0.79 and intraclass correlation coefficient ≥0.63; subscales correlated (P ≤ 0.05 with measures of well-being and satisfaction (0.12 ≤ r ≤ 0.71. In patients with type 1 diabetes, three subscales correlated (P < 0.05 with A1C.Conclusions: The psychometric properties of the DSC-R Cognitive Distress, Fatigue, Hyperglycemia, and Hypoglycemia suggest they may be utilized in clinical trials as reliable and valid measures of acute symptoms of diabetes.Keywords: Diabetes Symptom Checklist-Revised, DSC-R, type 1 diabetes, type 2 diabetes, psychometric validation

  6. Vertical equilibrium with sub-scale analytical methods for geological CO2 sequestration

    KAUST Repository

    Gasda, S. E.

    2009-04-23

    Large-scale implementation of geological CO2 sequestration requires quantification of risk and leakage potential. One potentially important leakage pathway for the injected CO2 involves existing oil and gas wells. Wells are particularly important in North America, where more than a century of drilling has created millions of oil and gas wells. Models of CO 2 injection and leakage will involve large uncertainties in parameters associated with wells, and therefore a probabilistic framework is required. These models must be able to capture both the large-scale CO 2 plume associated with the injection and the small-scale leakage problem associated with localized flow along wells. Within a typical simulation domain, many hundreds of wells may exist. One effective modeling strategy combines both numerical and analytical models with a specific set of simplifying assumptions to produce an efficient numerical-analytical hybrid model. The model solves a set of governing equations derived by vertical averaging with assumptions of a macroscopic sharp interface and vertical equilibrium. These equations are solved numerically on a relatively coarse grid, with an analytical model embedded to solve for wellbore flow occurring at the sub-gridblock scale. This vertical equilibrium with sub-scale analytical method (VESA) combines the flexibility of a numerical method, allowing for heterogeneous and geologically complex systems, with the efficiency and accuracy of an analytical method, thereby eliminating expensive grid refinement for sub-scale features. Through a series of benchmark problems, we show that VESA compares well with traditional numerical simulations and to a semi-analytical model which applies to appropriately simple systems. We believe that the VESA model provides the necessary accuracy and efficiency for applications of risk analysis in many CO2 sequestration problems. © 2009 Springer Science+Business Media B.V.

  7. Low reliability of sighted-normed verbal assessment scores when administered to children with visual impairments.

    Science.gov (United States)

    Morash, Valerie S; McKerracher, Amanda

    2017-03-01

    The most common and advocated assessment approach when a child cannot access visual materials is to use the verbal subscales of a test the psychologist already has and is familiar with. However, previous research indicates that children with visual impairments experience atypical verbal development. This raises the question of whether verbal subscale scores retain their reliability and interpretation validity when given to children with visual impairments. To answer this question, we administered a vocabulary subscale from a common intelligence test along with several nonverbal subscales to 15 early-blind adolescents (onset of ≤2 years). Reliability of only the vocabulary test scores was insufficient for high-stakes testing. This finding points to the broader issue of difficulties in assessing populations of exceptional children who experience atypical development trajectories, possibly making their assessment with common tests inappropriate. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

  8. An Evaluation of the Reliability, Construct Validity, and Factor Structure of the Static-2002R.

    Science.gov (United States)

    Jung, Sandy; Ennis, Liam; Hermann, Chantal A; Pham, Anna T; Choy, Alberto L; Corabian, Gabriela; Hook, Tarah

    2017-03-01

    The fundamental psychometric properties of the subscales found in the Static-2002R, an actuarial measure of sexual recidivism risk, were evaluated in the current study. Namely, the reliability, concurrent and construct validity, and factor structure of the Static-2002R subscales were examined with a sample of 372 adult male sex offenders. In addition to using validated measures of sexual violence risk to examine concurrent validity, construct-related measures taken from extant risk measures and psychometric tests were correlated with three of the subscales to assess overall construct validity. Moderate support was found for the reliability of the Static-2002R. The concurrent and construct validity of the General Criminality, Persistence of Sexual Offending, and Deviant Sexual Interest subscales were supported. Generally, these findings further support the Static-2002R as a valid sex offender risk appraisal instrument that encompasses multiple distinct, clinically relevant, risk domains.

  9. Maui Smart Grid Demonstration Project Managing Distribution System Resources for Improved Service Quality and Reliability, Transmission Congestion Relief, and Grid Support Functions

    Energy Technology Data Exchange (ETDEWEB)

    none,

    2014-09-30

    The Maui Smart Grid Project (MSGP) is under the leadership of the Hawaii Natural Energy Institute (HNEI) of the University of Hawaii at Manoa. The project team includes Maui Electric Company, Ltd. (MECO), Hawaiian Electric Company, Inc. (HECO), Sentech (a division of SRA International, Inc.), Silver Spring Networks (SSN), Alstom Grid, Maui Economic Development Board (MEDB), University of Hawaii-Maui College (UHMC), and the County of Maui. MSGP was supported by the U.S. Department of Energy (DOE) under Cooperative Agreement Number DE-FC26-08NT02871, with approximately 50% co-funding supplied by MECO. The project was designed to develop and demonstrate an integrated monitoring, communications, database, applications, and decision support solution that aggregates renewable energy (RE), other distributed generation (DG), energy storage, and demand response technologies in a distribution system to achieve both distribution and transmission-level benefits. The application of these new technologies and procedures will increase MECO’s visibility into system conditions, with the expected benefits of enabling more renewable energy resources to be integrated into the grid, improving service quality, increasing overall reliability of the power system, and ultimately reducing costs to both MECO and its customers.

  10. The Persian version of Trinity Amputation and Prosthetics Experience Scale: translation, factor structure, reliability and validity.

    Science.gov (United States)

    Mazaheri, Masood; Fardipour, Shima; Salavati, Mahyar; Hadadi, Mohammad; Negahban, Hossein; Bahramizadeh, Mahmood; Khosrozadeh, Fatemeh

    2011-01-01

    The purpose of the present study was to translate the Trinity Amputation and Prosthetics Experience Scale (TAPES) into Persian and to investigate its psychometric properties. A sample of 182 Persian-speaker individuals with lower limb amputation completed the TAPES questionnaire, of whom 103 individuals completed the Short Form 36 Health survey as well. The TAPES was re-administered to 41 participants in the retest session, with an interval of 5-7 days between the two sessions. Internal consistency, test-retest reproducibility, dimensionality, item internal consistency and discriminant validity and construct validity were assessed. Cronbach's α's were greater than the cut-off point of 0.70 for all subscales with the exception of social adjustment subscale. Minimum intraclass correlation coefficient of 0.70 was exceeded by all subscales with the exception of social activity subscale. Principle component analysis performed on each section of the TAPES revealed loading of all items on their corresponding factors. The exceptions were item 4 of social adjustment subscale and the single item of weight subscale. Most items were stronger measures of their hypothesised subscale than the other subscales. In terms of construct validity, 75% of a priori hypotheses were confirmed. The Persian version of TAPES seems to be a reliable and valid measure of psychological adaptation to artificial limb.

  11. Reliability between online raters with varying familiarities of a region: Microscale Audit of Pedestrian Streetscapes (MAPS).

    Science.gov (United States)

    Zhu, Wenfei; Sun, Yuliang; Kurka, Jonathan; Geremia, Carrie; Engelberg, Jessa K; Cain, Kelli; Conway, Terry; Sallis, James F; Hooker, Steven P; Adams, Marc A

    2017-11-01

    To test inter-rater reliability of the online Microscale Audit of Pedestrian Streetscapes (MAPS) tool between raters with varying familiarities of Phoenix, Arizona. The online MAPS tool, based on the MAPS in-field audit tool and scoring system, was used for audits. Sixty route pairs, 141 segment pairs, and 92 crossing pairs in Phoenix were included. Each route, segment or crossing was audited by two independent raters: one rater in Phoenix and the other in San Diego, California, respectively. Item, subscale scores, and total scores reliability analyses were computed using Kappa or intra-class correlation coefficient (ICC). The route overall score had substantial reliability (ICC: 0.832). Of the route subscale and overall scores, sixteen out of twenty had moderate to substantial reliability (ICC: 0.616-0.906), and the four subscales had fair reliability (ICC: 0.409-0.563). Sixteen out of twenty scores in segment and crossing sections demonstrated fair to substantial reliability (ICC: 0.448-0.897), and the remaining four had slight reliability (ICC: 0.348-0.364). Most of the online MAPS items, subscales, and overall scores demonstrated fair to substantial reliability between raters with varied familiarities of the Phoenix area. Results support use of online MAPS to measure microscale elements of the built environment by raters unfamiliar with a region.

  12. An assessment of the test–retest reliability of the New Nordic Diet score

    Directory of Open Access Journals (Sweden)

    Helga Birgit Bjørnarå

    2015-08-01

    Full Text Available Background: There is a growing interest in the New Nordic Diet (NND as a potentially health promoting, environmentally friendly, and palatable regional diet. Also, dietary scores are gaining ground as a complementary approach for examining relations between dietary patterns and various health outcomes. A score assessing adherence to the NND has earlier been published, yet not tested for reliability. Objective: To assess the test–retest reliability of the NND score in a sample of parents of toddlers, residing in Southern Norway. Design: A questionnaire survey was completed on two occasions, approximately 14 days apart, by 67 parents of toddlers [85% females, mean age 34 years (SD=5.3 years]. The NND score was constructed from 24 items and comprised 10 subscales that summarize meal pattern and intake of typical Nordic foods. Each subscale was dichotomized by the median and assigned values of ‘0’ or ‘1’. Adding the subscales yielded a score ranging from 0 to 10, which was further trichotomized. Test–retest reliability of the final NND score and individual subscales was assessed by Pearson's correlation coefficient and Spearman's rank correlation coefficient, respectively. Additionally, cross tabulation and kappa measure of agreement (k were used to assess the test–retest agreement of classification into the NND score, and the subscales. Results: Test–retest correlations of the NND score and subscales were r=0.80 (Pearson and r=0.54–0.84 (Spearman, respectively, all p<0.001. There were 69% (k=0.52 and 67–88% (k=0.32–0.76 test–retest correct classification of the trichotomized score and the dichotomized subscales, respectively. Conclusion: The NND score and the 10 subscales appear to have acceptable test–retest reliability when tested in a sample of parents of toddlers.

  13. Test-retest reliability of the Holyoake Codependency Index with Australian students.

    Science.gov (United States)

    Dear, Greg E

    2004-04-01

    The Holyoake Codependency Index is a 13-item self-report measure of three aspects of codependency: External Focus, Self-sacrifice, and a sense of being overwhelmed by another person's problematic behavior (termed Reactivity). Previous studies have supported internal validity and the internal consistency and construct validity of the subscales. The present scores for 59 students indicate full scale test-retest reliability of .88 and for subscales (.76 to .82) over a 3-wk. interval.

  14. Metrology automation reliability

    Science.gov (United States)

    Chain, Elizabeth E.

    1996-09-01

    At Motorola's MOS-12 facility automated measurements on 200- mm diameter wafers proceed in a hands-off 'load-and-go' mode requiring only wafer loading, measurement recipe loading, and a 'run' command for processing. Upon completion of all sample measurements, the data is uploaded to the factory's data collection software system via a SECS II interface, eliminating the requirement of manual data entry. The scope of in-line measurement automation has been extended to the entire metrology scheme from job file generation to measurement and data collection. Data analysis and comparison to part specification limits is also carried out automatically. Successful integration of automated metrology into the factory measurement system requires that automated functions, such as autofocus and pattern recognition algorithms, display a high degree of reliability. In the 24- hour factory reliability data can be collected automatically on every part measured. This reliability data is then uploaded to the factory data collection software system at the same time as the measurement data. Analysis of the metrology reliability data permits improvements to be made as needed, and provides an accurate accounting of automation reliability. This reliability data has so far been collected for the CD-SEM (critical dimension scanning electron microscope) metrology tool, and examples are presented. This analysis method can be applied to such automated in-line measurements as CD, overlay, particle and film thickness measurements.

  15. Separating the Domains of Oppositional Behavior: Comparing Latent Models of the Conners’ Oppositional Subscale

    Science.gov (United States)

    Kuny, Ana V.; Althoff, Robert R.; Copeland, William; Bartels, Meike; Beijsterveldt, Van; Baer, Julie; Hudziak, James J.

    2012-01-01

    OBJECTIVE Although Oppositional Defiant Disorder (ODD) is usually considered the mildest of the disruptive behavior disorders, it is a key factor in predicting young adult anxiety and depression and is distinguishable from normal childhood behavior. In an effort to understand possible subsets of oppositional defiant behavior (ODB) which may differentially predict outcome, we used Latent Class Analysis (LCA) of mother’s report on the Conners’ Parent Rating Scales Revised Short Forms (CPRS-R:S). METHOD Data were obtained from mother’s report for Dutch twins (7 year-old [n = 7,597], 10 year-old [n = 6,548], and 12 year-old [n = 5,717]) from the Netherlands Twin Registry. Samples partially overlapped at ages 7 and 10 (19% overlapping) and at ages 10 and 12 (30% overlapping), but not at ages 7 and 12. Oppositional defiant behavior was measured using the 6-item Oppositional subscale of the CPRS-R:S. Multilevel LCA with robust standard error estimates was performed using Latent Gold to control for twin-twin dependence in the data. Class assignment across ages was determined and an estimate of heritability for each class was calculated. Comparisons to maternal report Child Behavior Checklist (CBCL) scores were examined using linear mixed models at each age, corrected for multiple comparisons. RESULTS The LCA identified an optimal solution of 4-classes across age groups: Class 1 was associated with no or low symptom endorsement (69–75% of the children), class 2 was characterized by defiance (11–12%), class 3 was characterized by irritability (9–11%), and class 4 was associated with elevated scores on all symptoms (5–8%). Odds ratios for twins being in the same class at each successive age point were higher within classes across ages than between classes. Heritability within the two “intermediate” classes was nearly as high as for the class with all symptoms, except for boys at age 12. Children in the Irritable Class were more likely to have mood symptoms

  16. Reliable adherence to a COPD care bundle mitigates system-level failures and reduces COPD readmissions: a system redesign using improvement science.

    Science.gov (United States)

    Zafar, Muhammad Ahsan; Panos, Ralph J; Ko, Jonathan; Otten, Lisa C; Gentene, Anthony; Guido, Maria; Clark, Katherine; Lee, Caroline; Robertson, Jamie; Alessandrini, Evaline A

    2017-11-01

    Readmissions of chronic obstructive pulmonary disease (COPD) have devastating effects on patient quality-of-life, disease progression and healthcare cost. Effective interventions to reduce COPD readmissions are needed. Reduce 30-day all-cause readmissions by (1) creating a COPD care bundle that addresses care delivery failures, (2) using improvement science to achieve 90% bundle adherence. An 800-bed academic hospital in Ohio, USA. The COPD 30-day all-cause readmission rate was 22.7% from August 2013 to September 2015. We performed a cross-sectional study of COPD 30-day readmissions from October 2014 to March 2015 to identify care delivery failures. We interviewed readmitted patients with COPD to identify their needs after discharge. A multidisciplinary team created a care bundle designed to mitigate system failures. Using a quasi-experimental study and 'Model for Improvement', we redesigned care delivery to improve bundle adherence. We used statistical process control charts to analyse bundle adherence and all-cause 30-day readmissions. Cross-sectional review of the index (first-time) admissions revealed COPD was the most common readmission diagnosis and identified 42 system-level failures. The most prevalent failures were deficient inhaler regimen at discharge, late or non-existent follow-up appointments, and suboptimal discharge instructions. Patient interviews revealed confusing discharge instructions, especially regarding inhaler use. The COPD care-bundle components were: (1) appropriate inhaler regimen, (2) 30-day inhaler supply, (3) inhaler education on the device available postdischarge, (4) follow-up within 15 days (5) standardised patient-centred discharge instructions. The adherence to completing bundle components reached 90% in 5.5 months and was sustained. The COPD 30-day readmission rate decreased from 22.7% to 14.7%. Patients receiving all bundle components had a readmission rate of 10.9%. As a balancing measure for the targeted reduction in

  17. A scaling method for combustion stability rating of coaxial gas liquid injectors in a subscale chamber

    Energy Technology Data Exchange (ETDEWEB)

    Sohn, Chae Hoon; Kim, Young Jun [Sejong Univ., Seoul (Korea, Republic of); Kim, Young Mog [Korea Aerospace Research Institute, Daejeon (Korea, Republic of); Pikalov, Valery P. [Research Institute of Chemical Machine Building, Sergiev Posad (Russian Federation)

    2012-11-15

    A scaling method to examine combustion stability characteristics of a coaxial injector is devised based on the acoustics and combustion dynamics in a chamber. The method is required for a subscale test of stability rating with a model chamber, which is cost effective compared with an actual full scale test. First, scaling and similarity rules are considered for stability rating and thereby, three conditions of acoustic, hydrodynamic, and flame condition similarities are proposed. That is, for acoustic similarity, the natural or resonant frequencies in the actual chamber should be maintained in the model chamber. And, two parameters of density ratio and velocity ratio are derived for the requirement of hydrodynamic and flame condition similarities between the actual and the model conditions. Next, one example of an actual combustion chamber with high performance is selected and the proposed scaling method is applied to the chamber for understanding of the method. The design operating condition for a model test is presented by mass flow rates of propellants. Stability boundaries can be identified on the coordinate plane of chamber pressure and mixture ratio of fuel and oxidizer by applying the scaling method.

  18. Static Aeroelastic Scaling and Analysis of a Sub-Scale Flexible Wing Wind Tunnel Model

    Science.gov (United States)

    Ting, Eric; Lebofsky, Sonia; Nguyen, Nhan; Trinh, Khanh

    2014-01-01

    This paper presents an approach to the development of a scaled wind tunnel model for static aeroelastic similarity with a full-scale wing model. The full-scale aircraft model is based on the NASA Generic Transport Model (GTM) with flexible wing structures referred to as the Elastically Shaped Aircraft Concept (ESAC). The baseline stiffness of the ESAC wing represents a conventionally stiff wing model. Static aeroelastic scaling is conducted on the stiff wing configuration to develop the wind tunnel model, but additional tailoring is also conducted such that the wind tunnel model achieves a 10% wing tip deflection at the wind tunnel test condition. An aeroelastic scaling procedure and analysis is conducted, and a sub-scale flexible wind tunnel model based on the full-scale's undeformed jig-shape is developed. Optimization of the flexible wind tunnel model's undeflected twist along the span, or pre-twist or wash-out, is then conducted for the design test condition. The resulting wind tunnel model is an aeroelastic model designed for the wind tunnel test condition.

  19. Development of improved processing and evaluation methods for high reliability structural ceramics for advanced heat engine applications, Phase 1. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Pujari, V.K.; Tracey, D.M.; Foley, M.R.; Paille, N.I.; Pelletier, P.J.; Sales, L.C.; Wilkens, C.A.; Yeckley, R.L. [Norton Co., Northboro, MA (United States)

    1993-08-01

    The program goals were to develop and demonstrate significant improvements in processing methods, process controls and non-destructive evaluation (NDE) which can be commercially implemented to produce high reliability silicon nitride components for advanced heat engine applications at temperatures to 1,370{degrees}C. The program focused on a Si{sub 3}N{sub 4}-4% Y{sub 2}O{sub 3} high temperature ceramic composition and hot-isostatic-pressing as the method of densification. Stage I had as major objectives: (1) comparing injection molding and colloidal consolidation process routes, and selecting one route for subsequent optimization, (2) comparing the performance of water milled and alcohol milled powder and selecting one on the basis of performance data, and (3) adapting several NDE methods to the needs of ceramic processing. The NDE methods considered were microfocus X-ray radiography, computed tomography, ultrasonics, NMR imaging, NMR spectroscopy, fluorescent liquid dye penetrant and X-ray diffraction residual stress analysis. The colloidal consolidation process route was selected and approved as the forming technique for the remainder of the program. The material produced by the final Stage II optimized process has been given the designation NCX 5102 silicon nitride. According to plan, a large number of specimens were produced and tested during Stage III to establish a statistically robust room temperature tensile strength database for this material. Highlights of the Stage III process demonstration and resultant database are included in the main text of the report, along with a synopsis of the NCX-5102 aqueous based colloidal process. The R and D accomplishments for Stage I are discussed in Appendices 1--4, while the tensile strength-fractography database for the Stage III NCX-5102 process demonstration is provided in Appendix 5. 4 refs., 108 figs., 23 tabs.

  20. A Chinese version of the City of Hope Quality of Life-Ostomy Questionnaire: validity and reliability assessment.

    Science.gov (United States)

    Gao, Wenjun; Yuan, Changrong; Wang, Jichuan; Du, Jiarui; Wu, Huiqiao; Qian, Xiaojie; Hinds, Pamela S

    2013-01-01

    The City of Hope Quality of Life-Ostomy Questionnaire is a widely accepted scale to assess quality of life in ostomy patients. However, the validity and reliability of the Chinese version (C-COH) have not been studied. The objective of the study was to assess the validity and reliability of the C-COH among ostomy patients sampled from Shanghai from August 2010 to June 2011. Content validity was examined based on the reviews of a panel of 10 experts; test-retest was conducted to assess the item reliabilities of the scale; a pilot sample (n = 274) was selected to explore the factorial structure of the C-COH using exploratory factor analysis; a validation sample (n = 370) was selected to confirm the findings from the exploratory study using confirmatory factor analysis (CFA). Statistical package SPSS version 16.0 was used for the exploratory factor analysis, and Amos 17.0 was used for the CFA. The C-COH was developed by modifying 1 item and excluding 11 items from the original scale. Four factors/subscales (physical well-being, psychological well-being, social well-being, and spiritual well-being) were identified and confirmed in the C-COH The scale reliabilities estimated from the CFA results for the 4 subscales were 0.860, 0.885, 0.864, and 0.686, respectively. Findings support the reliability and validity of the C-COH. The C-COH could be a useful measure of the level of quality of life among Chinese patients with a stoma and may provide important intervention implications for healthcare providers to help improve the life quality of patients with a stoma.

  1. Less Is More: Using Static-2002R Subscales to Predict Violent and General Recidivism Among Sexual Offenders.

    Science.gov (United States)

    Babchishin, Kelly M; Hanson, R Karl; Blais, Julie

    2016-04-01

    Given that sexual offenders are more likely to reoffend with a nonsexual offense than a sexual offense, it is useful to have risk scales that predict general recidivism among sexual offenders. In the current study, we examined the extent to which two commonly used risk scales for sexual offenders (Static-99R and Static-2002R) predict violent and general recidivism, and whether it would be possible to improve predictive accuracy for these outcomes by revising their items. Based on an aggregated sample of 3,536 adult male sex offenders from Canada, the United States, and Europe (average age of 39 years), we found that a scale created from the Age at Release item and the General Criminality subscale of Static-2002R predicted nonsexual violent, any violent, and general recidivism significantly better than Static-99R or Static-2002R total scores. The convergent validity of this new scale (Brief Assessment of Recidivism Risk-2002R [BARR-2002R]) was examined in a new, independent data set of Canadian high-risk adult male sex offenders (N = 360) where it was found to be highly correlated with other risk assessment tools for general recidivism and the Psychopathy Checklist-Revised (PCL-R), as well as demonstrated similar discrimination and calibration as in the development sample. Instead of using total scores from the Static-99R or Static-2002R, we recommend that evaluators use the BARR-2002R for predicting violent and general recidivism among sex offenders, and for screening for the psychological dimension of antisocial orientation. © The Author(s) 2015.

  2. Photovoltaic module reliability workshop

    Science.gov (United States)

    Mrig, L.

    The paper and presentations compiled in this volume form the Proceedings of the fourth in a series of Workshops sponsored by Solar Energy Research Institute (SERI/DOE) under the general theme of photovoltaic module reliability during the period 1986 to 1990. The reliability photovoltaic (PV) modules/systems is exceedingly important along with the initial cost and efficiency of modules if the PV technology has to make a major impact in the power generation market, and for it to compete with the conventional electricity producing technologies. The reliability of photovoltaic modules has progressed significantly in the last few years as evidenced by warrantees available on commercial modules of as long as 12 years. However, there is still need for substantial research and testing required to improve module field reliability to levels of 30 years or more. Several small groups of researchers are involved in this research, development, and monitoring activity around the world. In the U.S., PV manufacturers, DOE laboratories, electric utilities and others are engaged in the photovoltaic reliability research and testing. This group of researchers and others interested in this field were brought together under SERI/DOE sponsorship to exchange the technical knowledge and field experience as related to current information in this important field. The papers presented here reflect this effort.

  3. Photovoltaic module reliability workshop

    Energy Technology Data Exchange (ETDEWEB)

    Mrig, L. (ed.)

    1990-01-01

    The paper and presentations compiled in this volume form the Proceedings of the fourth in a series of Workshops sponsored by Solar Energy Research Institute (SERI/DOE) under the general theme of photovoltaic module reliability during the period 1986--1990. The reliability Photo Voltaic (PV) modules/systems is exceedingly important along with the initial cost and efficiency of modules if the PV technology has to make a major impact in the power generation market, and for it to compete with the conventional electricity producing technologies. The reliability of photovoltaic modules has progressed significantly in the last few years as evidenced by warranties available on commercial modules of as long as 12 years. However, there is still need for substantial research and testing required to improve module field reliability to levels of 30 years or more. Several small groups of researchers are involved in this research, development, and monitoring activity around the world. In the US, PV manufacturers, DOE laboratories, electric utilities and others are engaged in the photovoltaic reliability research and testing. This group of researchers and others interested in this field were brought together under SERI/DOE sponsorship to exchange the technical knowledge and field experience as related to current information in this important field. The papers presented here reflect this effort.

  4. Validity and Reliability of the Czech Version of the Amsterdam Preoperative Anxiety and Information Scale (APAIS).

    Science.gov (United States)

    Zeleníková, Renáta; Homzová, Pavlína; Homza, Miroslav; Bužgová, Radka

    2017-10-01

    The purpose of this study was to validate the Czech version of the Amsterdam Preoperative Anxiety and Information Scale (APAIS) in adult patients undergoing elective surgery. A cross-sectional study. Data were collected from July 2012 to January 2013. For reliability and validity testing, two instruments measuring preoperative anxiety were administered to the participants on the same occasion, (APAIS and the Spielberg State Anxiety Inventory (STAI-S)). The sample consisted of 344 patients undergoing elective surgery. Reliability of APAIS anxiety subscale measured by Cronbach's alpha was 0.91. Reliability of APAIS information subscale measured by Cronbach's alpha was 0.78. The APAIS anxiety subscale correlated significantly with the STAI-S (0.69). Women scored significantly higher on anxiety scales than men. APAIS may be a useful tool to measure preoperative anxiety in Czech patients undergoing elective surgery. Copyright © 2016 American Society of PeriAnesthesia Nurses. Published by Elsevier Inc. All rights reserved.

  5. The development of the items-easy (Ie) and items-difficult (Id) subscales for the MMPI-A.

    Science.gov (United States)

    Krakauer, S Y; Archer, R P; Gordon, R A

    1993-06-01

    This research involves the development, validation, and cross-validation of the Items-Easy (Ie) and Items-Difficult (Id) subscales for the Minnesota Multiphasic Personality Inventory-Adolescent (MMPI-A; Butcher et al., 1992). These subscales were designed to assess the degree to which reading comprehension deficits may be responsible for significant elevations of validity Scale F and the standard clinical scales on adolescents' MMPI-A profiles. A difference score, bared on the two 13-item subscales, was created in order to compare subjects' responses to subsets of the more comprehensible (Ie) and less comprehensible (Id) items within the test. Hit rate, sensitivity, specificity, positive predictive power, and negative predictive power were calculated on the basis of simple (Id - Ie) and weighted (3Id - 1Ie) difference scores for the validation (N = 495) and cross-validation (N = 264) samples, and for specific high-F profile subsamples. Although some of the indices reflected classification accuracy as high as 95%, none of the indices yielded consistently high results across the various samples and subsamples. It has been concluded that the Ie and Id subscales should be used only for research purposes at this time.

  6. Validity of the Sleep Subscale of the Diagnostic Assessment for the Severely Handicapped-II (DASH-II)

    Science.gov (United States)

    Matson, Johnny L.; Malone, Carrie J.

    2006-01-01

    Currently there are no available sleep disorder measures for individuals with severe and profound intellectual disability. We, therefore, attempted to establish the external validity of the "Diagnostic Assessment for the Severely Handicapped-II" (DASH-II) sleep subscale by comparing daily observational sleep data with the responses of…

  7. Comparison of behavioral activation subscales of Gray’s original reinforcement sensitivity theory in opioid and methamphetamine dependent patients

    Directory of Open Access Journals (Sweden)

    Amir Ghaderi

    2017-10-01

    Results: The methamphetamine-dependents group had a higher BAS-DR subscale score than the opioid dependent group (P0.05. The BAS-RR scores of the methamphetamine-dependents group were higher than the other two groups (P

  8. North American Electric Reliability Council (NERC) Reliability Coordinators

    Data.gov (United States)

    Department of Homeland Security — ERC is an international regulatory authority that works to improve the reliability of the bulk power system in North America. NERC works with many different regional...

  9. Longitudinal validity and reliability of the Myeloma Patient Outcome Scale (MyPOS) was established using traditional, generalizability and Rasch psychometric methods.

    Science.gov (United States)

    Ramsenthaler, Christina; Gao, Wei; Siegert, Richard J; Schey, Steve A; Edmonds, Poly M; Higginson, Irene J

    2017-11-01

    The Myeloma Patient Outcome Scale (MyPOS) was developed to measure quality of life in routine clinical care. The aim of this study was to determine its longitudinal validity, reliability, responsiveness to change and its acceptability. This 14-centre study recruited patients with multiple myeloma. At baseline and then every two months for 5 assessments, patients completed the MyPOS. Psychometric properties evaluated were as follows: (a) confirmatory factor analysis and scaling assumptions (b) reliability: Generalizability theory and Rasch analysis, (c) responsiveness and minimally important difference (MID) relating changes in scores between baseline and subsequent assessments to an external criterion, (d) determining the acceptability of self-monitoring. 238 patients with multiple myeloma were recruited. Confirmatory factor analysis found three subscales; criteria for scaling assumptions were satisfied except for gastrointestinal items and the Healthcare support scale. Rasch analysis identified limitations of suboptimal scale-to-sample targeting, resulting in floor effects. Test-retest reliability indices were good (R = > 0.97). Responsiveness analysis yielded an MID of +2.5 for improvement and -4.5 for deterioration. The MyPOS demonstrated good longitudinal measurement properties, with potential areas for revision being the Healthcare Support subscale and the rating scale. The new psychometric approaches should be used for testing validity of monitoring in clinical settings.

  10. The genetic and environmental structure of the character sub-scales of the temperament and character inventory in adolescence.

    Science.gov (United States)

    Lester, Nigel; Garcia, Danilo; Lundström, Sebastian; Brändström, Sven; Råstam, Maria; Kerekes, Nóra; Nilsson, Thomas; Cloninger, C Robert; Anckarsäter, Henrik

    2016-01-01

    The character higher order scales (self-directedness, cooperativeness, and self-transcendence) in the temperament and character inventory are important general measures of health and well-being [Mens Sana Monograph 11:16-24 (2013)]. Recent research has found suggestive evidence of common environmental influence on the development of these character traits during adolescence. The present article expands earlier research by focusing on the internal consistency and the etiology of traits measured by the lower order sub-scales of the character traits in adolescence. The twin modeling analysis of 423 monozygotic pairs and 408 same sex dizygotic pairs estimated additive genetics (A), common environmental (C), and non-shared environmental (E) influences on twin resemblance. All twins were part of the on-going longitudinal Child and Adolescent Twin Study in Sweden (CATSS). The twin modeling analysis suggested a common environmental contribution for two out of five self-directedness sub-scales (0.14 and 0.23), for three out of five cooperativeness sub-scales (0.07-0.17), and for all three self-transcendence sub-scales (0.10-0.12). The genetic structure at the level of the character lower order sub-scales in adolescents shows that the proportion of the shared environmental component varies in the trait of self-directedness and in the trait of cooperativeness, while it is relatively stable across the components of self-transcendence. The presence of this unique shared environmental effect in adolescence has implications for understanding the relative importance of interventions and treatment strategies aimed at promoting overall maturation of character, mental health, and well-being during this period of the life span.

  11. 2015 NREL Photovoltaic Module Reliability Workshops

    Energy Technology Data Exchange (ETDEWEB)

    Kurtz, Sarah [National Renewable Energy Laboratory (NREL), Golden, CO (United States)

    2017-09-14

    NREL's Photovoltaic (PV) Module Reliability Workshop (PVMRW) brings together PV reliability experts to share information, leading to the improvement of PV module reliability. Such improvement reduces the cost of solar electricity and promotes investor confidence in the technology--both critical goals for moving PV technologies deeper into the electricity marketplace.

  12. 2016 NREL Photovoltaic Module Reliability Workshop

    Energy Technology Data Exchange (ETDEWEB)

    Kurtz, Sarah [National Renewable Energy Laboratory (NREL), Golden, CO (United States)

    2017-09-07

    NREL's Photovoltaic (PV) Module Reliability Workshop (PVMRW) brings together PV reliability experts to share information, leading to the improvement of PV module reliability. Such improvement reduces the cost of solar electricity and promotes investor confidence in the technology - both critical goals for moving PV technologies deeper into the electricity marketplace.

  13. Space transportation main engine reliability and safety

    Science.gov (United States)

    Monk, Jan C.

    1991-01-01

    Viewgraphs are used to illustrate the reliability engineering and aerospace safety of the Space Transportation Main Engine (STME). A technology developed is called Total Quality Management (TQM). The goal is to develop a robust design. Reducing process variability produces a product with improved reliability and safety. Some engine system design characteristics are identified which improves reliability.

  14. Reliability of Wireless Sensor Networks

    Science.gov (United States)

    Dâmaso, Antônio; Rosa, Nelson; Maciel, Paulo

    2014-01-01

    Wireless Sensor Networks (WSNs) consist of hundreds or thousands of sensor nodes with limited processing, storage, and battery capabilities. There are several strategies to reduce the power consumption of WSN nodes (by increasing the network lifetime) and increase the reliability of the network (by improving the WSN Quality of Service). However, there is an inherent conflict between power consumption and reliability: an increase in reliability usually leads to an increase in power consumption. For example, routing algorithms can send the same packet though different paths (multipath strategy), which it is important for reliability, but they significantly increase the WSN power consumption. In this context, this paper proposes a model for evaluating the reliability of WSNs considering the battery level as a key factor. Moreover, this model is based on routing algorithms used by WSNs. In order to evaluate the proposed models, three scenarios were considered to show the impact of the power consumption on the reliability of WSNs. PMID:25157553

  15. Improving the reliability of female fertility breeding values using type and milk yield traits that predict energy status in Australian Holstein cattle.

    Science.gov (United States)

    González-Recio, O; Haile-Mariam, M; Pryce, J E

    2016-01-01

    The objectives of this study were (1) to propose changing the selection criteria trait for evaluating fertility in Australia from calving interval to conception rate at d 42 after the beginning of the mating season and (2) to use type traits as early fertility predictors, to increase the reliability of estimated breeding values for fertility. The breeding goal in Australia is conception within 6 wk of the start of the mating season. Currently, the Australian model to predict fertility breeding values (expressed as a linear transformation of calving interval) is a multitrait model that includes calving interval (CVI), lactation length (LL), calving to first service (CFS), first nonreturn rate (FNRR), and conception rate. However, CVI has a lower genetic correlation with the breeding goal (conception within 6 wk of the start of the mating season) than conception rate. Milk yield, type, and fertility data from 164,318 cow sired by 4,766 bulls were used. Principal component analysis and genetic correlation estimates between type and fertility traits were used to select type traits that could subsequently be used in a multitrait analysis. Angularity, foot angle, and pin set were chosen as type traits to include in an index with the traits that are included in the multitrait fertility model: CVI, LL, CFS, FNRR, and conception rate at d 42 (CR42). An index with these 8 traits is expected to achieve an average bull first proof reliability of 0.60 on the breeding objective (conception within 6 wk of the start of the mating season) compared with reliabilities of 0.39 and 0.45 for CR42 only or the current 5-trait Australian model. Subsequently, we used the first eigenvector of a principal component analysis with udder texture, bone quality, angularity, and body condition score to calculate an energy status indicator trait. The inclusion of the energy status indicator trait composite in a multitrait index with CVI, LL, CFS, FNRR, and CR42 achieved a 12-point increase in

  16. Reliability and validity of the multidimensional scale of perceived social support in Chinese mainland patients with methadone maintenance treatment.

    Science.gov (United States)

    Zhou, Kaina; Li, Hengxin; Wei, Xiaoli; Yin, Juan; Liang, Peifeng; Zhang, Hongmei; Kou, Lingling; Hao, Mengmeng; You, Lijuan; Li, Xiaomei; Zhuang, Guihua

    2015-07-01

    The multidimensional scale of perceived social support (MSPSS) is a valid tool for assessing perceived support from family, friends and significant others. However, evidence about reliability and validity of the MSPSS in Chinese mainland patients with methadone maintenance treatment (MMT) is lacking. The patients (n=1212) being admitted to the first two largest MMT clinics in Xi'an were recruited in the study. Reliability was estimated with Cronbach's α and intra-class correlation (ICC). Convergent and discriminant validity was assessed using item-subscale correlation. Factorial validity was examined using exploratory and confirmatory factor analysis. The patients answered the questions of MSPSS at baseline and re-test after 6months, respectively. Cronbach's α of the overall MSPSS was 0.92 (subscales range: 0.84-0.89). ICC of the overall MSPSS was 0.65 (subscales range: 0.57-0.64). Better convergent validity (r≥0.40) was demonstrated by the satisfactory hypothesized item-subscale correlation. All of the hypothesized item-subscale correlations were higher than the correlations between the hypothesized items and other subscales, indicating better discriminant validity. Two factors were extracted from the 12 items, with factor 1 mainly covering friends and significant others subscales (explained 55.56% variance) and factor 2 mainly covering family subscale (explained 11.77% variance). In comparison with the proposed three-subscale model, the two-factor observed model did not fit well in this sample according to model fit indices. The MSPSS has acceptable reliability and convergent/discriminant validity in Chinese mainland MMT patients. The proposed three-factor model of MSPSS is much better fit than the two-factor observed model in this study. Findings of the study will provide evidence of psychometric properties of the MSPSS in MMT patient population and expand the use of the MSPSS in clinical MMT context. Copyright © 2015 Elsevier Inc. All rights reserved.

  17. Measurement properties of the Brazilian version of the Penn Shoulder Score (PSS-Brazil): reliability, validity, and responsiveness.

    Science.gov (United States)

    de Souza, Marcela Bembo; Martins, Jaqueline; Hotta, Gisele Harumi; de Oliveira, Anamaria Siriani

    2015-02-01

    Clinical measurement. To determine the reliability, validity, and responsiveness of the Brazilian version of the Penn Shoulder Score (PSS-Brazil) in patients with shoulder dysfunctions. Several questionnaires assessing shoulder dysfunctions are available in Brazil, but the measurement properties of most of them, such as the PSS, have not yet been tested. Internal consistency, measurement error, construct validity, and floor and ceiling effects were evaluated in 62 patients, 36 of whom completed the questionnaire at baseline and after 2 to 7 days to assess test-retest reliability. Responsiveness was determined with 50 patients who completed the questionnaire at an initial visit and after 4 weeks of physical therapy. The PSS-Brazil displayed acceptable internal consistency, with a Cronbach alpha of .92. Test-retest reliability was excellent, with an intraclass correlation coefficient of 0.95; the standard error of measurement and minimal detectable change were 12.8 and 14.4 points, respectively. A high correlation was obtained between the PSS and the Shoulder Pain and Disability Index (0.96) and the Disabilities of the Arm, Shoulder and Hand questionnaire (0.86). There was moderate correlation between the PSS and its subscales and the pain and function subscales of the Medical Outcomes Study 36-Item Short-Form Health Survey (0.40-0.68). There was high responsiveness, with an effect size of 0.95 and standardized response mean of 1.13 for patients with improvement of shoulder dysfunction, and adequate area under the curve of 0.81. No floor or ceiling effects were observed. The PSS-Brazil is a reliable, valid, and responsive measure for assessing patients with shoulder dysfunction.

  18. Reliability Studies in the Real World

    Science.gov (United States)

    Roesch, William J.

    This chapter is intended to give a nontraditional look at reliability of compound semiconductors. It is a review of the five main stages of reliability analysis. Although essential, the first three stages are separated as those traditional tests which are particularly applicable for process development and material selection phases. The remaining two reliability stages are the focus of real life. These later stages are the tools used for improving reliability of established processes and families of products where significant changes and switches to new materials are not feasible. While all five steps are necessary in reliability studies, the methods of establishing and improving reliability are different.

  19. 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

  20. Reliability and construct validity of a new Danish translation of the Prosthesis Evaluation Questionnaire in a population of Danish amputees

    DEFF Research Database (Denmark)

    Christensen, Jan; Doherty, Patrick; Bjorner, Jakob Bue

    2017-01-01

    . Estimates for standard error of measurement (SEM) were calculated based on reliability estimates. Construct validity was evaluated by testing using hypotheses testing. Results: Reliability estimates (ICC/Cronbach’s alpha) for the nine subscales were: Social Burden (0.85/0.76), Appearance (0...

  1. The psychometric properties of the Social Training and Achievement Record: II. Reliabilities and concurrent validities.

    Science.gov (United States)

    Olurin, J; Sturmey, P

    1989-10-01

    Three studies are reported which investigated the test-retest and inter-rater reliabilities of the Social Training and Achievement Record as well as concurrent validities with intelligence. Reliabilities of total and sub-scale scores as well as individual items are reported. Test-retest reliabilities over the period of one month were good for total scores, subscale scores and individual items. Inter-rater reliabilities were more modest. At times, inter-rater reliabilities of a small proportion of items were only at chance levels. Concurrent validities with Raven's Matrices and the Weschler Adult Intelligence Scale were comparable with other measures of adaptive behaviour. The role of direct observation in the assessment of adaptive behaviour, in particular with respect to individual skills being selected for teaching, is discussed.

  2. Development and testing of mobile technology for community park improvements: validity and reliability of the eCPAT application with youth.

    Science.gov (United States)

    Besenyi, Gina M; Diehl, Paul; Schooley, Benjamin; Turner-McGrievy, Brie M; Wilcox, Sara; Stanis, Sonja A Wilhelm; Kaczynski, Andrew T

    2016-12-01

    Creation of mobile technology environmental audit tools can provide a more interactive way for youth to engage with communities and facilitate participation in health promotion efforts. This study describes the development and validity and reliability testing of an electronic version of the Community Park Audit Tool (eCPAT). eCPAT consists of 149 items and incorporates a variety of technology benefits. Criterion-related validity and inter-rater reliability were evaluated using data from 52 youth across 47 parks in Greenville County, SC. A large portion of items (>70 %) demonstrated either fair or moderate to perfect validity and reliability. All but six items demonstrated excellent percent agreement. The eCPAT app is a user-friendly tool that provides a comprehensive assessment of park environments. Given the proliferation of smartphones, tablets, and other electronic devices among both adolescents and adults, the eCPAT app has potential to be distributed and used widely for a variety of health promotion purposes.

  3. Development of a Low-Cost, Subscale Test System to Evaluate Particle Impingement Erosion in Nozzle Ablative Materials

    Science.gov (United States)

    Lansing, Matthew D.; Lawrence, Timothy W.; Gordon, Gail H. (Technical Monitor)

    2001-01-01

    This viewgraph presentation gives an overview on the development of a low-cost, subscale test system to evaluate particle impingement erosion in nozzle ablative materials. Details are given on the need for a new test bed, solid fuel torch components, solid fuel torch test, additional uses for the solid fuel torch, the development of a supersonic blast tube (SSBT), and particle impingement material discrimination.

  4. The use of Spielberger’s State-Trait Personality Inventory (trait anxiety subscale) with naval subaquatic specialists

    OpenAIRE

    Van Wijk, Charles H

    2014-01-01

    Objectives: Panic behavior poses a particular threat to the health and safety of subaquatic occupational specialists. Trait anxiety has previously been identified as a marker of panic behavior under water, and Spielberger’s State-Trait Personality Inventory (trait anxiety subscale) has been previously used to measure trait anxiety among subaquatic specialists. Using archived data, the trait anxiety scores of subaquatic specialists were analyzed to meet 3 objectives: 1stly – to develop a trait...

  5. The Child Behavior Checklist-Obsessive-Compulsive Subscale Detects Severe Psychopathology and Behavioral Problems Among School-Aged Children.

    Science.gov (United States)

    Saad, Laura O; do Rosario, Maria C; Cesar, Raony C; Batistuzzo, Marcelo C; Hoexter, Marcelo Q; Manfro, Gisele G; Shavitt, Roseli G; Leckman, James F; Miguel, Eurípedes C; Alvarenga, Pedro G

    2017-05-01

    The aims of this study were (1) to assess obsessive-compulsive symptoms (OCS) dimensionally in a school-aged community sample and to correlate them with clinical and demographical variables; (2) to determine a subgroup with significant OCS ("at-risk for OCD") using the Child Behavior Checklist (CBCL-OCS) and (3) to compare it with the rest of the sample; (4) To review the CBCL-OCS subscale properties as a screening tool for pediatric OCD. Data from the Brazilian High Risk Cohort were analyzed. The presence and severity of OCS were assessed through the CBCL-OCS subscale. DSM-IV psychiatric diagnoses were obtained by the Developmental and Well-Being Assessment. Behavioral problems were assessed using the Strengths and Difficulties Questionnaire, the Youth Strengths Inventory, and the CBCL internalizing and externalizing behavior subscales. A total of 2512 (mean age: 8.86 ± 1.84 years; 55.0% male) children were included. Moderate correlations were found between OCS severity and functional impairment (r = 0.36, p behavioral problems (p behavioral patterns and psychiatric comorbidities (e.g., tics [odds ratios, OR = 6.41, p approach suggests that the presence of OCS in children is associated with higher rates of comorbidity, behavioral problems, and impairment. The "at-risk for OCD" group defined by the CBCL revealed a group of patients phenotypically similar to full blown OCD.

  6. Industrial application of fluidized bed combustion. Phase I, task 4: sub-scale unit testing and data analysis. Volume I. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Goodstine, S.L.; Accortt, J.I.; Harris, R.D.; Kantersaria, P.P.; Matthews, F.T.; Jones, B.C.; Jukkola, G.D.

    1979-12-01

    Combustion Engineering, under contract with the Department of Energy, has developed, designed, and is constructing a 50,000 lbs steam/hr Industrial FBC Demonstration Plant. The plant will provide steam for space heating at the Great Lakes Naval Base in North Chicago, Illinois. Its operation will enable industry to objectively appraise the performance, reliability, and economics of FBC technology. A hot sub-scale unit (SSU), simulating the operating conditions of the demonstration plant, has been constructed and operated at Combustion Engineering's Kreisinger Development Laboratory in Windsor, Connecticut. The SSU facility has served as a valuable developmental tool in establishing the performance characteristics of the FBC process and equipment as used in the larger Demonstration Plant. Experience gained during more than 2000 hours of operation, including the analytical results derived from an extensive test program of 1500 hours operation, has defined problems and identified solutions in engineering the larger FBC Demonstration Plant. This report presents documentation of the results of the SSU test program.

  7. Mining a database of single amplified genomes from Red Sea brine pool extremophiles-improving reliability of gene function prediction using a profile and pattern matching algorithm (PPMA).

    KAUST Repository

    Grötzinger, Stefan W.

    2014-04-07

    Reliable functional annotation of genomic data is the key-step in the discovery of novel enzymes. Intrinsic sequencing data quality problems of single amplified genomes (SAGs) and poor homology of novel extremophile\\'s genomes pose significant challenges for the attribution of functions to the coding sequences identified. The anoxic deep-sea brine pools of the Red Sea are a promising source of novel enzymes with unique evolutionary adaptation. Sequencing data from Red Sea brine pool cultures and SAGs are annotated and stored in the Integrated Data Warehouse of Microbial Genomes (INDIGO) data warehouse. Low sequence homology of annotated genes (no similarity for 35% of these genes) may translate into false positives when searching for specific functions. The Profile and Pattern Matching (PPM) strategy described here was developed to eliminate false positive annotations of enzyme function before progressing to labor-intensive hyper-saline gene expression and characterization. It utilizes InterPro-derived Gene Ontology (GO)-terms (which represent enzyme function profiles) and annotated relevant PROSITE IDs (which are linked to an amino acid consensus pattern). The PPM algorithm was tested on 15 protein families, which were selected based on scientific and commercial potential. An initial list of 2577 enzyme commission (E.C.) numbers was translated into 171 GO-terms and 49 consensus patterns. A subset of INDIGO-sequences consisting of 58 SAGs from six different taxons of bacteria and archaea were selected from six different brine pool environments. Those SAGs code for 74,516 genes, which were independently scanned for the GO-terms (profile filter) and PROSITE IDs (pattern filter). Following stringent reliability filtering, the non-redundant hits (106 profile hits and 147 pattern hits) are classified as reliable, if at least two relevant descriptors (GO-terms and/or consensus patterns) are present. Scripts for annotation, as well as for the PPM algorithm, are available

  8. Mining a database of single amplified genomes from Red Sea brine pool extremophiles – Improving reliability of gene function prediction using a profile and pattern matching algorithm (PPMA

    Directory of Open Access Journals (Sweden)

    Stefan Wolfgang Grötzinger

    2014-04-01

    Full Text Available Reliable functional annotation of genomic data is the key-step in the discovery of novel enzymes. Intrinsic sequencing data quality problems of single amplified genomes (SAGs and poor homology of novel extremophile’s genomes pose significant challenges for the attribution of functions to the coding sequences identified. The anoxic deep-sea brine pools of the Red Sea are a promising source of novel enzymes with unique evolutionary adaptation. Sequencing data from Red Sea brine pool cultures and SAGs are annotated and stored in the INDIGO data warehouse. Low sequence homology of annotated genes (no similarity for 35% of these genes may translate into false positives when searching for specific functions. The Profile & Pattern Matching (PPM strategy described here was developed to eliminate false positive annotations of enzyme function before progressing to labor-intensive hyper-saline gene expression and characterization. It utilizes InterPro-derived Gene Ontology (GO-terms (which represent enzyme function profiles and annotated relevant PROSITE IDs (which are linked to an amino acid consensus pattern. The PPM algorithm was tested on 15 protein families, which were selected based on scientific and commercial potential. An initial list of 2,577 E.C. numbers was translated into 171 GO-terms and 49 consensus patterns. A subset of INDIGO-sequences consisting of 58 SAGs from six different taxons of bacteria and archaea were selected from 6 different brine pool environments. Those SAGs code for 74,516 genes, which were independently scanned for the GO-terms (profile filter and PROSITE IDs (pattern filter. Following stringent reliability filtering, the non-redundant hits (106 profile hits and 147 pattern hits are classified as reliable, if at least two relevant descriptors (GO-terms and/or consensus patterns are present. Scripts for annotation, as well as for the PPM algorithm, are available through the INDIGO website.

  9. State-oriented plant management. New concept improves reliability and availability of industrial systems; Zustandsorientierte Anlagenwirtschaft. Neues Konzept verbessert die Zuverlaessigkeit und Verfuegbarkeit von Industrieanlagen

    Energy Technology Data Exchange (ETDEWEB)

    Reinert, U. [Deutscher Kraftfahrzeug-Ueberwachungsverein e.V. (DEKRA), Stuttgart (Germany); Fichtner, H.P. [Ramsys GmbH, St. Ingbert (Germany)

    2000-07-01

    Conventional maintenance management systems as a rule are not based on heterogeneous real plant data. The data are not available in a database and thus cannot be updated consistently. This will reduce plant availabilty and reliability. A new concept is presented which makes it possible to develop new strategies for plant maintenance and optimisation. [German] Herkoemmliche Instandhaltungs-Managementsysteme basieren in der Regel nicht auf den heterogenen Daten der Anlagen-Istsituation. Diese sind nicht in Form einer Datenbank vorhanden und koennen daher nicht konsistent gepflegt werden. Eine Verschlechterung der Anlagenzuverlaessigkeit und -verfuegbarkeit ist die Folge. Durch das vorgestellte Anlagenwirtschaftskonzept wird die Entwicklung von neuen Instandhaltungs- und Optimierungsstrategien moeglich. (orig.)

  10. IMPROVING THE RELIABILITY OF THE POWER CIRCUIT OF THE ELECTRIC TRAINS ЕР2Т AND ЕПЛ2Т

    Directory of Open Access Journals (Sweden)

    N. H. Visin

    2010-02-01

    Full Text Available The transitional processes in shunt circuit of traction engines, which armatures and excitation windings are connected in non-conducting direction as to the flowing power current, are considered in this paper. The changes in the control circuits of braking switch and in the shunt power circuit of traction engines with additional mounting a resistor of 0.5 Ohm are proposed. All this modernization will allow increasing greatly the operation reliability of power circuit of ЭР2Т and ЕПЛ2Т electric locomotives during their service life.

  11. Development and validation of subscales to assess perceived support for self-management of mood or emotional problems: Results from a randomized trial.

    Science.gov (United States)

    McCusker, Jane; Haggerty, Jeannie; De Raad, Manon; Belzile, Eric; Bouharaoui, Fatima; Beaulieu, Christine; Yaffe, Mark; Ciampi, Antonio

    2017-06-10

    To validate 2 new patient-reported measures of self-management support from health professionals for mood and emotional problems. The sample comprised primary care patients with chronic physical conditions and co-morbid depressive symptoms enrolled in a randomized trial of telephone coaching of a depression self-care intervention (n=120). At 6-month follow-up, patients completed 2 subscales with respect to support for self-management of their chronic physical condition(s): 1) Self-Management Information (SMInfo-Phys); and 2) Care Plan (CP-Phys) and equivalent subscales adapted to assess self-management support for mood and emotional problems: SMInfo-Mood and CP-Mood. Subscale scoring was assessed with Item Response Theory (IRT) analysis. Convergent validity of the mood subscales was assessed. The sensitivity of the mood and physical condition subscales to mental health interventions was assessed with generalized estimating equations (GEE). The mood subscales were associated with relevant measures of perceived unmet mental health needs. Both SMInfo-Mood and CP-Mood were sensitive to the coaching intervention; CP-Mood was also sensitive to receipt of depression treatment outside the trial. This study provides preliminary evidence for the validity of the 2 new subscales. The subscales may be used to assess perceived health professional support for self-management of mood and emotional problems. Copyright © 2017 Elsevier B.V. All rights reserved.

  12. Reliability and Validity Study of the Attitude towards Mathematics Instruments Short Form

    Directory of Open Access Journals (Sweden)

    Güney HACIÖMEROĞLU

    2017-05-01

    Full Text Available Purpose of this study was to investigate the reliability and validity of the Turkish form of the Attitude Towards Mathematics Instrument Short Form developed by Lim and Chapman (2013. In this study, data gathered from 310 elementary students were utilized for Exploratory and Confirmatory Factor Analysis to determine the structure of factor loading. The factor loading among the sub-scales were different from original. Confirmatory Factor analysis revealed that the model was acceptable. There were three sub-scales, value, self-confidence, enjoyment and motivation. Cronbach’s alpha coefficient for the overall instrument was calculated as .84, respectively. The adapted instrument includes three sub-scales: value (α=.91, self-confidence (α=.86, enjoyment and motivation (α=.82. Turkish adaptation of the questionnaire is valid and reliable and appropriate to use in Turkish culture.

  13. Highly improved reliability of amber light emitting diode with Ca -α-SiAlON phosphor in glass formed by gas pressure sintering for automotive applications.

    Science.gov (United States)

    Yoon, Chang-Bun; Kim, Sanghyun; Choi, Sung-Woo; Yoon, Chulsoo; Ahn, Sang Hyeon; Chung, Woon Jin

    2016-04-01

    Phosphor in glass (PiG) with 40 wt% of Ca-α-SiAlON phosphor and 60 wt% of Pb-free silicate glass was synthesized and mounted on a high-power blue LED to make an amber LED for automotive applications. Gas pressure sintering was applied after the conventional sintering process was used to achieve fully dense PiG plates. Changes in photoluminescence spectra and color coordination were inspected by varying the thickness of the plates that were mounted after optical polishing and machining. A trade-off between luminous flux and color purity was observed. The commercial feasibility of amber PiG packaged LED, which can satisfy international regulations for automotive components, was successfully demonstrated by examining the practical reliability under 85% humidity at an 85°C condition.

  14. Improvement of reliability and speed of phase change memory devices with N7.9(Ge46.9Bi7.2Te45.9 films

    Directory of Open Access Journals (Sweden)

    J. H. Park

    2015-08-01

    Full Text Available In this study, we propose a nitrogen-incorporated GeBiTe ternary phase of N7.9(Ge46.9Bi7.2Te45.9 as a phase change material for reliable PCM (Phase Change Memory with high speed operation. We found that the N7.9(Ge46.9Bi7.2Te45.9 film shows the resistance value of 40 kΩ after annealing at 440oC for 10 minutes, which is much higher than the value of 3.4 kΩ in the case of conventional N7.0(Ge22.0Sb22.0Te56.0 films. A set operation time of 14 nsec was achieved in the devices due to the increased probability of the nucleation by the addition of the elemental Bi. The long data retention time of 10 years at 85oC on the base of 1% failure was obtained as the result of higher activation energy of 2.52 eV for the crystallization compared to the case of N7.0(Ge22.0Sb22.0Te56.0 film, in which the activation energy is 2.1 eV. In addition, a reset current reduction of 27% and longer cycles of endurance as much as 2 order of magnitude compared to the case of N7.0(Ge22.0Sb22.0Te56.0 were observed at a set operation time of 14 nsec. Our results show that N7.9(Ge46.9Bi7.2Te45.9 is highly promising for use as a phase change material in reliable PCMs with high performance and also in forthcoming storage class memory applications, too.

  15. Modeling and simulation of a GOX/kerosene subscale rocket combustion chamber with film cooling

    Science.gov (United States)

    Höglauer, C.; Kniesner, B.; Knab, O.; Schlieben, G.; Kirchberger, C.; Silvestri, S.; Haidn, O. J.

    2015-12-01

    Detailed knowledge on the heat transfer mechanisms is crucial for the design of reliable and efficient rocket engines. Due to the high heat loads of the combustion chamber walls and the corrosive hot gases, film cooling is often applied supplementary or even as a primary cooling technique. Nevertheless, the dominating processes determining the film effectiveness under the conditions representative for rocket combustors are still not fully understood. In context of the national research program Transregio SFB/TRR-40, TEKAN and TARES, the Institute for Flight Propulsion (LFA) of the Technische Universität München (TUM) and Airbus Defence and Space carry out experimental and numerical investigations on heat transfer and film cooling techniques at application-relevant combustion pressures and temperatures. In this paper, results from film cooling experiments and numerical simulations with liquid and transcritical kerosene films in a water-cooled GOX/kerosene rocket combustion chamber are presented. The tests have been performed at two different combustion chamber pressures and with two different throat diameters to study the influence of Reynolds and Mach number. In the numerical investigations, a major issue has been the modeling of kerosene films in sub- and transcritical state. For the modeling Airbus Defence and Space's in-house tool, Rocflam-II has been applied. The main goal of Rocflam-II is to provide a tool package for the simulation of a wide range of rocket combustion devices, validated against experimental data. This includes the modeling of propellant injection, atomization, mixing, combustion, wall heat transfer, film modeling as well as the conjugate heat transfer into the chamber wall and the cooling channels.

  16. The Reliability and Validity of Scores from the Children's Version of the Perception of Success Questionnaire.

    Science.gov (United States)

    Liukkonen, Jarmo; Leskinen, Esko

    1999-01-01

    Analyzed the reliability and validity of scores of 557 14-year-old Finnish male soccer players on the children's version of the Perception of Success Questionnaire (G. Roberts and others, 1998). Internal consistency coefficients for the two subscales' scores were high, and scores on both scales had strong construct validity. (LSD)

  17. Using Self-Concept Instruments with High-Ability College Students: Reliability and Validity Evidence

    Science.gov (United States)

    Rinn, Anne N.; Cunningham, Lindy G.

    2008-01-01

    This study investigated the reliability and validity of the academic subscales of Marsh's Self-Description Questionnaire III and Neeman and Harter's Self-Perception Profile for College Students for use with high-ability college students. Participants included 100 high-ability college students and 196 average-ability college students enrolled in a…

  18. Crosscultural adaptation, reliability, and validity of the Japanese version of the neck disability index.

    Science.gov (United States)

    Nakamaru, Koji; Vernon, Howard; Aizawa, Junya; Koyama, Takayuki; Nitta, Osamu

    2012-10-01

    Translation and psychometric testing. To translate and culturally adapt the Neck Disability Index (NDI) and to assess the reliability and validity of the Japanese version of the NDI (NDI-J) in Japanese outpatients with neck pain. To date, no previous report exists on the translation process and psychometric testing of the NDI-J. The NDI was translated and culturally adapted into Japanese in accordance with published guidelines. A total of 110 outpatients with neck pain participated in the study. Psychometric testing included reliability by internal consistency (Cronbach α) and test-retest reliability (intraclass correlation coefficient), factor analysis, convergent validity by comparing the NDI-J with the short-form health survey (Pearson correlation) and responsiveness (unpaired t tests, standard error of measurement, and minimal detectable change). The Cronbach α of the NDI-J was 0.88 and the intraclass correlation coefficient for test-retest reliability was 0.91 (95% confidence interval, 0.82-0.95). Factor analysis demonstrated a 2-factor structure, explaining 61.8% of the total variance. The correlation between the NDI-J and the short-form health survey, version 36, subscales ranged from good to fair (-0.25 to -0.51). The analysis of responsiveness was calculated with an unpaired t test after 3 weeks of treatment demonstrating a statistically significant difference between the stable and improved patients (P ≤ 0.05). The standard error of measurement and minimal detectable change were calculated as 2.9 and 6.8, respectively. The NDI-J is a valid, reliable, and responsive tool that can be used to assess neck pain in Japanese outpatients.

  19. Analysis of the reliability and validity of the Turkish version of the intermittent and constant osteoarthritis pain questionnaire.

    Science.gov (United States)

    Erel, Suat; Şimşek, İbrahim Engin; Özkan, Hüseyin

    2015-01-01

    The aim of this study was to analyze the validity and reliability of the Turkish version (ICOAP-TR) of the intermittent and constant osteoarthritis pain (ICOAP) questionnaire in patients with knee osteoarthritis (OA). Thirty-eight volunteer patients diagnosed with knee OA answered the questionnaire twice with an interval of 2-4 days. The reliability of the measurement was assessed using Cronbach's alpha coefficient and intraclass correlation (ICC) for test-retest reliability. Criterion validity was tested against the Western Ontario and McMaster Universities Arthritis Index (WOMAC) pain score and visual analog scale (VAS) designed to assess the perceived discomfort rated by the patient. Test-retest reliability was found to be ICC=0.942 for total score, 0.902 for constant pain subscale, and 0.945 for intermittent pain subscale. Internal consistency was tested using Cronbach's alpha and was found to be 0.970 for total score, 0.948 for constant pain subscale, and 0.972 for intermittent pain subscale. For criterion validity, the correlation between the total score of ICOAP-TR and WOMAC pain subscale was r=0.779 (pVAS was r=0.570 (pvalid instrument to be used with patients with knee OA.

  20. Reliability of goniometric measurements.

    Science.gov (United States)

    Boone, D C; Azen, S P; Lin, C M; Spence, C; Baron, C; Lee, L

    1978-11-01

    This study determined the intratester and intertester variability and reliability of goniometric measurements taken by four physical therapists on upper and lower extremity motions of normal male subjects. The same subjects were measured once weekly for four weeks by testers with varied experience in goniometry. Data were analyzed by analyses of variance with repeated measures. Intratester variation for all measurements was less than intertester variation. Further, intertester variation was less for the three upper extremity motions than for those of the lower extremity. These findings indicate the necessity for using the same tester when effects of treatment are evaluated. When the same tester measures the same movement, increases in joint motion of at least three to four degrees determine improvement for either the upper or lower extremity. When more than one tester, however, measures the same movement, increases in joint motion should exceed five degrees for the upper extremity and six degrees for the lower extremity to determine improvement.

  1. Environmentally Responsible Aviation (ERA) Project - N+2 Advanced Vehicle Concepts Study and Conceptual Design of Subscale Test Vehicle (STV) Final Report

    Science.gov (United States)

    Bonet, John T.; Schellenger, Harvey G.; Rawdon, Blaine K.; Elmer, Kevin R.; Wakayama, Sean R.; Brown, Derrell L.; Guo, Yueping

    2011-01-01

    NASA has set demanding goals for technology developments to meet national needs to improve fuel efficiency concurrent with improving the environment to enable air transportation growth. A figure shows NASA's subsonic transport system metrics. The results of Boeing ERA N+2 Advanced Vehicle Concept Study show that the Blended Wing Body (BWB) vehicle, with ultra high bypass propulsion systems have the potential to meet the combined NASA ERA N+2 goals. This study had 3 main activities. 1) The development of an advanced vehicle concepts that can meet the NASA system level metrics. 2) Identification of key enabling technologies and the development of technology roadmaps and maturation plans. 3) The development of a subscale test vehicle that can demonstrate and mature the key enabling technologies needed to meet the NASA system level metrics. Technology maturation plans are presented and include key performance parameters and technical performance measures. The plans describe the risks that will be reduced with technology development and the expected progression of technical maturity.

  2. Classification of quality of life subscales within the ICF framework in burn research: identifying overlaps and gaps.

    Science.gov (United States)

    Meirte, J; van Loey, N E E; Maertens, K; Moortgat, P; Hubens, G; Van Daele, U

    2014-11-01

    Quality of life (QOL) is one of the leading outcomes in burn care research. This study classifies subscales of common QOL measures within the International Classification of Functioning disability and health (ICF) framework to determine to which extent the measures are complementary or overlapping and to investigate whether the instruments are able to describe the full spectrum of patients' functioning. A literature search was performed to determine the most frequently used questionnaires in burn research. The subscales of the three mostly used questionnaires were classified within the ICF framework. Two generic measures, the Short Form-36 items (SF-36) and the European Quality of Life 5 Dimensions (EQ-5D), and a disease specific measure, the Burn Specific Health Scale-Brief (BSHS-B), were analyzed. The BSHS-B covered most domains and was the only scale that included personal factors. The SF-36 included only one domain in the activity limitations and similar to the EQ-5D no contextual factors were included. Environmental factors were not addressed in the questionnaires, even though these may have an impact on the quality of life in patients with burns. To capture the full spectrum of dysfunctioning a combination of the BSHS-B with a generic questionnaire seems obligatory. However still some domains of functioning remain uncovered. Copyright © 2014 Elsevier Ltd and ISBI. All rights reserved.

  3. Reliability Assessment of Wind Turbines

    DEFF Research Database (Denmark)

    Sørensen, John Dalsgaard

    2015-01-01

    but manufactured in series production based on many component tests, some prototype tests and zeroseries wind turbines. These characteristics influence the reliability assessment where focus in this paper is on the structural components. Levelized Cost Of Energy is very important for wind energy, especially when...... comparing to other energy sources. Therefore much focus is on cost reductions and improved reliability both for offshore and onshore wind turbines. The wind turbine components should be designed to have sufficient reliability level with respect to both extreme and fatigue loads but also not be too costly...... (and safe). In probabilistic design the single components are designed to a level of reliability, which accounts for an optimal balance between failure consequences, cost of operation & maintenance, material costs and the probability of failure. Furthermore, using a probabilistic design basis...

  4. Reliability assessment of Wind turbines

    DEFF Research Database (Denmark)

    Sørensen, John Dalsgaard

    2015-01-01

    but manufactured in series production based on many component tests, some prototype tests and zeroseries wind turbines. These characteristics influence the reliability assessment where focus in this paper is on the structural components. Levelized Cost Of Energy is very important for wind energy, especially when...... comparing to other energy sources. Therefore much focus is on cost reductions and improved reliability both for offshore and onshore wind turbines. The wind turbine components should be designed to have sufficient reliability level with respect to both extreme and fatigue loads but also not be too costly...... (and safe). In probabilistic design the single components are designed to a level of reliability, which accounts for an optimal balance between failure consequences, cost of operation & maintenance, material costs and the probability of failure. Furthermore, using a probabilistic design basis...

  5. A method for improving reliability and relevance of LCA reviews: the case of life-cycle greenhouse gas emissions of tap and bottled water.

    Science.gov (United States)

    Fantin, Valentina; Scalbi, Simona; Ottaviano, Giuseppe; Masoni, Paolo

    2014-04-01

    The purpose of this study is to propose a method for harmonising Life Cycle Assessment (LCA) literature studies on the same product or on different products fulfilling the same function for a reliable and meaningful comparison of their life-cycle environmental impacts. The method is divided in six main steps which aim to rationalize and quicken the efforts needed to carry out the comparison. The steps include: 1) a clear definition of the goal and scope of the review; 2) critical review of the references; 3) identification of significant parameters that have to be harmonised; 4) harmonisation of the parameters; 5) statistical analysis to support the comparison; 6) results and discussion. This approach was then applied to the comparative analysis of the published LCA studies on tap and bottled water production, focussing on Global Warming Potential (GWP) results, with the aim to identify the environmental preferable alternative. A statistical analysis with Wilcoxon's test confirmed that the difference between harmonised GWP values of tap and bottled water was significant. The results obtained from the comparison of the harmonised mean GWP results showed that tap water always has the best environmental performance, even in case of high energy-consuming technologies for drinking water treatments. The strength of the method is that it enables both performing a deep analysis of the LCA literature and obtaining more consistent comparisons across the published LCAs. For these reasons, it can be a valuable tool which provides useful information for both practitioners and decision makers. Finally, its application to the case study allowed both to supply a description of systems variability and to evaluate the importance of several key parameters for tap and bottled water production. The comparative review of LCA studies, with the inclusion of a statistical decision test, can validate and strengthen the final statements of the comparison. Copyright © 2014 Elsevier B.V. All

  6. Audio-Visual Biofeedback Does Not Improve the Reliability of Target Delineation Using Maximum Intensity Projection in 4-Dimensional Computed Tomography Radiation Therapy Planning

    Energy Technology Data Exchange (ETDEWEB)

    Lu, Wei, E-mail: wlu@umm.edu [Department of Radiation Oncology, University of Maryland School of Medicine, Baltimore, Maryland (United States); Neuner, Geoffrey A.; George, Rohini; Wang, Zhendong; Sasor, Sarah [Department of Radiation Oncology, University of Maryland School of Medicine, Baltimore, Maryland (United States); Huang, Xuan [Research and Development, Care Management Department, Johns Hopkins HealthCare LLC, Glen Burnie, Maryland (United States); Regine, William F.; Feigenberg, Steven J.; D' Souza, Warren D. [Department of Radiation Oncology, University of Maryland School of Medicine, Baltimore, Maryland (United States)

    2014-01-01

    Purpose: To investigate whether coaching patients' breathing would improve the match between ITV{sub MIP} (internal target volume generated by contouring in the maximum intensity projection scan) and ITV{sub 10} (generated by combining the gross tumor volumes contoured in 10 phases of a 4-dimensional CT [4DCT] scan). Methods and Materials: Eight patients with a thoracic tumor and 5 patients with an abdominal tumor were included in an institutional review board-approved prospective study. Patients underwent 3 4DCT scans with: (1) free breathing (FB); (2) coaching using audio-visual (AV) biofeedback via the Real-Time Position Management system; and (3) coaching via a spirometer system (Active Breathing Coordinator or ABC). One physician contoured all scans to generate the ITV{sub 10} and ITV{sub MIP}. The match between ITV{sub MIP} and ITV{sub 10} was quantitatively assessed with volume ratio, centroid distance, root mean squared distance, and overlap/Dice coefficient. We investigated whether coaching (AV or ABC) or uniform expansions (1, 2, 3, or 5 mm) of ITV{sub MIP} improved the match. Results: Although both AV and ABC coaching techniques improved frequency reproducibility and ABC improved displacement regularity, neither improved the match between ITV{sub MIP} and ITV{sub 10} over FB. On average, ITV{sub MIP} underestimated ITV{sub 10} by 19%, 19%, and 21%, with centroid distance of 1.9, 2.3, and 1.7 mm and Dice coefficient of 0.87, 0.86, and 0.88 for FB, AV, and ABC, respectively. Separate analyses indicated a better match for lung cancers or tumors not adjacent to high-intensity tissues. Uniform expansions of ITV{sub MIP} did not correct for the mismatch between ITV{sub MIP} and ITV{sub 10}. Conclusions: In this pilot study, audio-visual biofeedback did not improve the match between ITV{sub MIP} and ITV{sub 10}. In general, ITV{sub MIP} should be limited to lung cancers, and modification of ITV{sub MIP} in each phase of the 4DCT data set is recommended.

  7. Conceiving processes in atmospheric models-General equations, subscale parameterizations, and 'superparameterizations'

    Science.gov (United States)

    Gramelsberger, Gabriele

    The scientific understanding of atmospheric processes has been rooted in the mechanical and physical view of nature ever since dynamic meteorology gained ground in the late 19th century. Conceiving the atmosphere as a giant 'air mass circulation engine' entails applying hydro- and thermodynamical theory to the subject in order to describe the atmosphere's behaviour on small scales. But when it comes to forecasting, it turns out that this view is far too complex to be computed. The limitation of analytical methods precludes an exact solution, forcing scientists to make use of numerical simulation. However, simulation introduces two prerequisites to meteorology: First, the partitioning of the theoretical view into two parts-the large-scale behaviour of the atmosphere, and the effects of smaller-scale processes on this large-scale behaviour, so-called parametrizations; and second, the dependency on computational power in order to achieve a higher resolution. The history of today's atmospheric circulation modelling can be reconstructed as the attempt to improve the handling of these basic constraints. It can be further seen as the old schism between theory and application under new circumstances, which triggers a new discussion about the question of how processes may be conceived in atmospheric modelling.

  8. Wind Tunnel Test of Subscale Ringsail and Disk-Gap-Band Parachutes

    Science.gov (United States)

    Zumwalt, Carlie H.; Cruz, Juan R.; Keller, Donald F.; O'Farrell, Clara

    2016-01-01

    A subsonic wind tunnel test was conducted to determine the drag and static aerodynamic coefficients, as well as to capture the dynamic motions of a new Supersonic Ringsail parachute developed by the Low Density Supersonic Decelerator Project. To provide a comparison against current Mars parachute technology, the Mars Science Laboratory's Disk-Gap-Band parachute was also included in the test. To account for the effect of fabric permeability, two fabrics ("low" and "standard" permeability) were used to fabricate each parachute canopy type, creating four combinations of canopy type and fabric material. A wide range of test conditions were covered during the test, spanning Mach numbers from 0.09 to 0.5, and static pressures from 103 to 2116 pounds per square inch (psf) (nominal values). The fabric permeability is shown to have a first-order effect on the aerodynamic coefficients and dynamic motions of the parachutes. For example, for a given parachute type and test condition, models fabricated from "low" permeability fabric always have a larger drag coefficient than models fabricated from "standard" permeability material. This paper describes the test setup and conditions, how the results were analyzed, and presents and discusses a sample of the results. The data collected during this test is being used to create and improve parachute aerodynamic databases for use in flight dynamics simulations for missions to Mars.

  9. A comparative validation of the abbreviated Apathy Evaluation Scale (AES-10) with the Neuropsychiatric Inventory apathy subscale against diagnostic criteria of apathy.

    NARCIS (Netherlands)

    Leontjevas, R.; Evers-Stephan, A.; Smalbrugge, M.; Pot, A.M.; Thewissen, V.; Gerritsen, D.L.; Koopmans, R.T.C.M.

    2012-01-01

    OBJECTIVE: To compare the Neuropsychiatric Inventory apathy subscale (NPIa) with the abbreviated Apathy Evaluation Scale (AES-10) on discriminant validity and on their performance to distinguish residents as apathetic or nonapathetic. DESIGN: Cross-sectional design. SETTING: Nursing home.

  10. Hungarian adaptation of the Tinnitus Handicap Inventory: reliability and validity.

    Science.gov (United States)

    Bencsik, Beata; Tamás, László; Trimmel, Krisztina; Stauder, Adrienne

    2015-09-01

    The objective of this study was to determine the reliability and validity of the Hungarian version of the original Tinnitus Handicap Inventory (THI). In the study design the original THI (THI-US) was translated into Hungarian by three independent investigators. The final Hungarian version (THI-HUN) was constructed on the basis of these Hungarian interpretations and then administered to 72 patients suffering from chronic tinnitus. Construct validity was assessed using short version of Beck's Depression Inventory (BDI), Perceived Stress Scale (PSS4 version), Visual Analogue Scale (VAS) (loudness, annoyance and pitch of tinnitus), pure tone audiometry and tinnitometry. The 72 participants were 43 women and 29 men. Their mean age was 49.86 years with a mean tinnitus duration of 4.16 years. In the results THI-HUN and its subscales showed good internal consistency reliabilities (α = 0.95-0.74), with significant correlation between THI-HUN total score and subscales and the BDI, PSS4 and VAS annoyance. There was a high or moderate correlation between THI-HUN total score and VAS loudness, tinnitus duration, hearing loss and subjective perception of tinnitus loudness. The VAS pitch of tinnitus, the subjective perception of tinnitus pitch, age, gender and level of education did not show any correlation with THI-HUN total score. The test-retest reliability was high (r = 0.97). We conclude that a valid and reliable THI-HUN questionnaire was constructed.

  11. PV Systems Reliability Final Technical Report.

    Energy Technology Data Exchange (ETDEWEB)

    Lavrova, Olga [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Flicker, Jack David [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Johnson, Jay [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Armijo, Kenneth Miguel [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Gonzalez, Sigifredo [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Schindelholz, Eric John [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Sorensen, Neil R. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Yang, Benjamin Bing-Yeh [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2015-12-01

    The continued exponential growth of photovoltaic technologies paves a path to a solar-powered world, but requires continued progress toward low-cost, high-reliability, high-performance photovoltaic (PV) systems. High reliability is an essential element in achieving low-cost solar electricity by reducing operation and maintenance (O&M) costs and extending system lifetime and availability, but these attributes are difficult to verify at the time of installation. Utilities, financiers, homeowners, and planners are demanding this information in order to evaluate their financial risk as a prerequisite to large investments. Reliability research and development (R&D) is needed to build market confidence by improving product reliability and by improving predictions of system availability, O&M cost, and lifetime. This project is focused on understanding, predicting, and improving the reliability of PV systems. The two areas being pursued include PV arc-fault and ground fault issues, and inverter reliability.

  12. Reliability and internal validity of the michigan hand questionnaire.

    Science.gov (United States)

    Chung, Bryan T; Morris, Steven F

    2014-10-01

    The Michigan Hand Outcomes Questionnaire (MHQ) remains one of very few to be based on validated and systematic methods in its creation. However, test-retest reliability and internal validity have not been appropriately investigated in any other English-speaking population outside the original development sample. The objective of this study is to examine the reliability and internal validity of the MHQ in a Canadian population. All patients with a clinical hand problem but no hand immobilization who attended our Plastic Surgery Clinic were invited to participate in this study. Patients were asked to complete the MHQ, and then contacted to arrange for completion of the MHQ a second time. Internal validity was estimated using Cronbach alpha. Reliability was estimated using the method of Bland and Altman, and intraclass correlation coefficients. Correlation analysis between score differences and time between tests was performed. Full versions of the MHQ were completed by 116 participants on their initial visit, while only 77 participants completed a second MHQ. Cronbach alpha ranged from 0.84 to 0.95 for the MHQ subscales. Intraclass-correlation coefficients ranged from 0.71 to 0.84 for the subscales. The magnitude of the limits of agreement for the subscales ranged from 13.8 to 26.2. The difference in scores between the first and second tests was not related to the time between tests. The high values of Cronbach alpha indicate high internal validity, but that there may be redundancy between items in the MHQ, which could be eliminated without losing information. Reliability of the MHQ is considered moderate. The limits of agreement are considered wide, indicating potential issues with respect to interpretation of a change in score between 2 administrations of the MHQ.

  13. Validity and Reliability of the Alcohol, Smoking, and Substance Involvement Screening Test (ASSIST) in University Students.

    Science.gov (United States)

    Tiburcio Sainz, Marcela; Rosete-Mohedano, Ma Guadalupe; Natera Rey, Guillermina; Martínez Vélez, Nora Angélica; Carreño García, Silvia; Pérez Cisneros, Daniel

    2016-03-02

    The Alcohol, Smoking and Substance Involvement Screening Test (ASSIST), developed by the World Health Organization (WHO), has been used successfully in many countries, but there are few studies of its validity and reliability for the Mexican population. The objective of this study was to determine the psychometric properties of the self-administered ASSIST test in university students in Mexico. This was an ex post facto non-experimental study with 1,176 undergraduate students, the majority women (70.1%) aged 18-23 years (89.5%) and single (87.5%). To estimate concurrent validity, factor analysis and tests of reliability and correlation were carried out between the subscale for alcohol and AUDIT, those for tobacco and the Fagerström Test, and those for marijuana and DAST-20. Adequate reliability coefficients were obtained for ASSIST subscales for tobacco (alpha = 0.83), alcohol (alpha = 0.76), and marijuana (alpha = 0.73). Significant correlations were found only with the AUDIT (r = 0.71) and the alcohol subscale. The best balance of sensitivity and specificity of the alcohol subscale (83.8% and 80%, respectively) and the largest area under the ROC curve (81.9%) was found with a cutoff score of 8. The self-administered version of ASSIST is a valid screening instrument to identify at-risk cases due to substance use in this population.

  14. The Accelerator Reliability Forum

    CERN Document Server

    Lüdeke, Andreas; Giachino, R

    2014-01-01

    A high reliability is a very important goal for most particle accelerators. The biennial Accelerator Reliability Workshop covers topics related to the design and operation of particle accelerators with a high reliability. In order to optimize the over-all reliability of an accelerator one needs to gather information on the reliability of many different subsystems. While a biennial workshop can serve as a platform for the exchange of such information, the authors aimed to provide a further channel to allow for a more timely communication: the Particle Accelerator Reliability Forum [1]. This contribution will describe the forum and advertise it’s usage in the community.

  15. [Validity and Reliability of Korean Version of the Spiritual Care Competence Scale].

    Science.gov (United States)

    Chung, Mi Ja; Park, Youngrye; Eun, Young

    2016-12-01

    The aim of this study was to examine the validity and reliability of the Korean Version of the Spiritual Care Competence Scale (K-SCCS). A cross-sectional study design was used. The K-SCCS consisted of 26 questions to measure spiritual care competence of nurses. Participants, 228 nurses who had more than 3 years'experience as a nurse, completed the survey. Confirmatory factor analysis was used to examine the construct validity and correlations of K-SCCS and spiritual well-being (SWB) were used to examine the criterion validity of K-SCCS. Cronbach's alpha was used to test internal consistency. The construct and the criterion-related validity of K-SCCS were supported as measures of spiritual care competence. Cronbach's alpha was .95. Factor loadings of the 26 questions ranged from .60 to .96. Construct validity of K-SCCS was verified by confirmatory factor analysis (RMSEA=.08, CFI=.90, NFI=.85). Criterion validity compared to the SWB showed significant correlation (r=.44, pcompetence with validity and reliability. However, further study is needed to retest the verification of the factor analysis related to factor 2 (professionalisation and improving the quality of spiritual care) and factor 3 (personal support and patient counseling). Therefore, we recommend using the total score without distinguishing subscales.

  16. El análisis de criticidad, una metodología para mejorar la confiabilidad operacional // Criticality analysis , a methodology to improve the operational reliability.

    Directory of Open Access Journals (Sweden)

    R. Huerta Mendoza

    2000-10-01

    establecer prioridades, yfocalizar el esfuerzo que garantice el éxito maximizando la rentabilidad.Palabras claves: confiabilidad, criticidad, seguridad, ambiente, riesgo, disponibilidad, mejoramiento.___________________________________________________________________Abstract:The criticality analysis is a methodology that allows to establish the hierarchy or priorities of processes, systems andequipments, creating a structure that facilitates the taking of effective and correct decisions, addressing the effort and theresources in areas where it is more important or necessary to improve the operational dependability, based on the currentreality.The improvement of the operational dependability of any installation or their systems and components is associated withfour fundamental aspects: human dependability, dependability of the process, dependability of the design and thedependability of the maintenance. Regrettably, difficultly is in our hands limitless resources, so much economic as human,to be able to improve at the same time, these four aspects in all the areas of a company.The approaches to carry out a criticality analysis are associated with: security, surroundings, production, operation costsand maintenance, failure rate and repair time mainly. These approaches are related with a mathematical equation thatgenerates punctuation for each evaluated element.The generated list, result of a team work, allows to even and to homologate approaches to establish priorities, and focalisethe effort that guarantees the success maximizing the profitability..Key words:. PDVSA, dependability, criticality, security, surroundings, risk, readiness, improvement,changes.

  17. Space Launch System Base Heating Test: Sub-Scale Rocket Engine/Motor Design, Development & Performance Analysis

    Science.gov (United States)

    Mehta, Manish; Seaford, Mark; Kovarik, Brian; Dufrene, Aaron; Solly, Nathan

    2014-01-01

    ATA-002 Technical Team has successfully designed, developed, tested and assessed the SLS Pathfinder propulsion systems for the Main Base Heating Test Program. Major Outcomes of the Pathfinder Test Program: Reach 90% of full-scale chamber pressure Achieved all engine/motor design parameter requirements Reach steady plume flow behavior in less than 35 msec Steady chamber pressure for 60 to 100 msec during engine/motor operation Similar model engine/motor performance to full-scale SLS system Mitigated nozzle throat and combustor thermal erosion Test data shows good agreement with numerical prediction codes Next phase of the ATA-002 Test Program Design & development of the SLS OML for the Main Base Heating Test Tweak BSRM design to optimize performance Tweak CS-REM design to increase robustness MSFC Aerosciences and CUBRC have the capability to develop sub-scale propulsion systems to meet desired performance requirements for short-duration testing.

  18. Design and Analysis of Subscale and Full-Scale Buckling-Critical Cylinders for Launch Vehicle Technology Development

    Science.gov (United States)

    Hilburger, Mark W.; Lovejoy, Andrew E.; Thornburgh, Robert P.; Rankin, Charles

    2012-01-01

    NASA s Shell Buckling Knockdown Factor (SBKF) project has the goal of developing new analysis-based shell buckling design factors (knockdown factors) and design and analysis technologies for launch vehicle structures. Preliminary design studies indicate that implementation of these new knockdown factors can enable significant reductions in mass and mass-growth in these vehicles. However, in order to validate any new analysis-based design data or methods, a series of carefully designed and executed structural tests are required at both the subscale and full-scale levels. This paper describes the design and analysis of three different orthogrid-stiffeNed metallic cylindrical-shell test articles. Two of the test articles are 8-ft-diameter, 6-ft-long test articles, and one test article is a 27.5-ft-diameter, 20-ft-long Space Shuttle External Tank-derived test article.

  19. Diabetes fatalism and its emotional distress subscale are independent predictors of glycemic control among Lebanese patients with type 2 diabetes.

    Science.gov (United States)

    Sukkarieh-Haraty, Ola; Egede, Leonard E; Abi Kharma, Joelle; Bassil, Maya

    2017-09-04

    Achieving and sustaining optimal glycemic control in type 2 diabetes (T2DM) is difficult because of socio-cultural and psychosocial factors including diabetes fatalism. Diabetes fatalism is 'a complex psychological cycle characterized by perceptions of despair, hopelessness, and powerlessness'. The purpose of this paper is to explore whether diabetes fatalism and other psychosocial and socio-cultural variables are correlates of glycemic control in Lebanese population with T2DM. A convenience sample of 280 adult participants with T2DM were recruited from a major hospital in greater Beirut-Lebanon area and from the community. Diabetes fatalism was assessed using the Arabic version of 12-item Diabetes Fatalism Scale. Multiple linear regression models were used to assess the relationship between HbA1c and psychosocial and socio-cultural characteristics including diabetes fatalism. Four models were run to examine the independent association between HbA1c and diabetes fatalism and to identify which of the 3 subscales (emotional distress, spiritual coping and perceived self-efficacy) were associated with HbA1c. The mean age of the participants was 58.24(SD = 13.48) and the majority were females (53.76%), while 32.73% of the sample had diabetes for more than 10 years. Fully adjusted multiple linear regression models showed that higher scores on diabetes fatalism and the emotional distress subscale (P = 0.018) were significantly associated with higher HbA1c values. In addition, having diabetes for more than 11 years (P = 0.05) and a higher number of diabetes complications (P fatalism as an independent predictor of glycemic control among Lebanese. Future studies should further investigate this construct to guide interventions that can address it for better diabetes outcomes.

  20. Developing Reliable Life Support for Mars

    Science.gov (United States)

    Jones, Harry W.

    2017-01-01

    A human mission to Mars will require highly reliable life support systems. Mars life support systems may recycle water and oxygen using systems similar to those on the International Space Station (ISS). However, achieving sufficient reliability is less difficult for ISS than it will be for Mars. If an ISS system has a serious failure, it is possible to provide spare parts, or directly supply water or oxygen, or if necessary bring the crew back to Earth. Life support for Mars must be designed, tested, and improved as needed to achieve high demonstrated reliability. A quantitative reliability goal should be established and used to guide development t. The designers should select reliable components and minimize interface and integration problems. In theory a system can achieve the component-limited reliability, but testing often reveal unexpected failures due to design mistakes or flawed components. Testing should extend long enough to detect any unexpected failure modes and to verify the expected reliability. Iterated redesign and retest may be required to achieve the reliability goal. If the reliability is less than required, it may be improved by providing spare components or redundant systems. The number of spares required to achieve a given reliability goal depends on the component failure rate. If the failure rate is under estimated, the number of spares will be insufficient and the system may fail. If the design is likely to have undiscovered design or component problems, it is advisable to use dissimilar redundancy, even though this multiplies the design and development cost. In the ideal case, a human tended closed system operational test should be conducted to gain confidence in operations, maintenance, and repair. The difficulty in achieving high reliability in unproven complex systems may require the use of simpler, more mature, intrinsically higher reliability systems. The limitations of budget, schedule, and technology may suggest accepting lower and

  1. A study on the role of grain boundary engineering in promoting high-cycle fatigue resistance and improving reliability in nickel base superalloys for propulsion systems

    Science.gov (United States)

    Gao, Yong

    High-cycle fatigue, involving the premature initiation and/or rapid propagation of small cracks to failure due to high-frequency (vibratory) loading, remains the principal cause of failures in military gas-turbine propulsion systems. The objective of this study is to examine whether the resistance to high-cycle fatigue failures can be enhanced by grain-boundary engineering, i.e., through the modification of the spatial distribution and topology of the grain boundaries in the microstructure. While grain boundary engineering has been used to obtain significant improvements in intergranular corrosion and cracking, creep and cavitation behavior, toughness and plasticity, cold-work embrittlement, and weldability, only very limited, but positive, results exist for fatigue. Accordingly, using a commercial polycrystalline nickel base gamma/gamma' superalloy, ME3, as a typical engine disk material, sequential thermomechanical processing, involving alternate cycles of strain and annealing, is used to (i) modify the proportion of special grain boundaries, and (ii) interrupt the connectivity of the random boundaries in the grain boundary network. The processed microstructures are then subjected to fracture-mechanics based high cycle fatigue testing to evaluate how the crack initiation and small- and large-crack growth properties are affected and to examine how the altered grain boundary population and connectivity can influence growth rates and overall lifetimes. The effect of such grain-boundary engineering on the fatigue-crack-propagation behavior of large (˜8 to 20 mm), through-thickness cracks at 25, 700, and 800°C was examined. Although there was little influence of an increased special boundary fraction at ambient temperatures, the resistance to near-threshold crack growth was definitively improved at elevated temperatures, with fatigue threshold-stress intensities some 10 to 20% higher than at 25°C, concomitant with a lower proportion (˜20%) of intergranular

  2. Evidence of Reliability and Validity for a Children’s Auditory Continuous Performance Test

    Directory of Open Access Journals (Sweden)

    Michael J. Lasee

    2013-11-01

    Full Text Available Continuous Performance Tests (CPTs are commonly utilized clinical measures of attention and response inhibition. While there have been many studies of CPTs that utilize a visual format, there is considerably less research employing auditory CPTs. The current study provides initial reliability and validity evidence for the Auditory Vigilance Screening Measure (AVSM, a newly developed CPT. Participants included 105 five- to nine-year-old children selected from two rural Midwestern school districts. Reliability data for the AVSM was collected through retesting of 42 participants. Validity was evaluated through correlation of AVSM scales with subscales from the ADHD Rating Scale–IV. Test–retest reliability coefficients ranged from .62 to .74 for AVSM subscales. A significant (r = .31 correlation was obtained between the AVSM Impulsivity Scale and teacher ratings of inattention. Limitations and implications for future study are discussed.

  3. Half-Year Retest-Reliability of the Barratt Impulsiveness Scale–Short Form (BIS-15

    Directory of Open Access Journals (Sweden)

    Adrian Meule

    2015-03-01

    Full Text Available One of the most widely used instruments for the measurement of impulsivity is the Barratt Impulsiveness Scale (BIS-11. The short form of the BIS-11, the BIS-15, consists of 15 items representing the three subscales Attentional, Motor, and Non-Planning Impulsivity. In the current study, retest-reliabilities of BIS-15 scores were examined. Female university students completed the BIS-15 at the beginning of the first (n = 133 and second (n = 120 semesters. Half-year retest-reliability was rtt = .79 for the BIS-15 total score and ranged between rtt = .61 and .78 for the subscales. Considering the long time span of almost half a year between measurements, the total score of the BIS-15 has high retest-reliability and, thus, measures impulsivity as a stable personality trait.

  4. Human Reliability Program Overview

    Energy Technology Data Exchange (ETDEWEB)

    Bodin, Michael

    2012-09-25

    This presentation covers the high points of the Human Reliability Program, including certification/decertification, critical positions, due process, organizational structure, program components, personnel security, an overview of the US DOE reliability program, retirees and academia, and security program integration.

  5. The concurrent validity of the Problem Oriented Screening Instrument for Teenagers (POSIT) substance use/abuse subscale in adolescent patients in an urban federally qualified health center.

    Science.gov (United States)

    Kelly, Sharon M; O'Grady, Kevin E; Gryczynski, Jan; Mitchell, Shannon Gwin; Kirk, Arethusa; Schwartz, Robert P

    2017-01-01

    The Problem Oriented Screening Instrument for Teenagers (POSIT) substance use/abuse subscale has been validated with high school students, adolescents with criminal justice involvement, and adolescent substance use treatment samples using the Diagnostic and Statistical Manual of Mental Disorders (DSM)-III-R and DSM-IV. This study examines the concurrent validity of the POSIT's standard 17-item substance use/abuse subscale and a revised, shorter 11-item version using DSM-5 substance use disorder diagnoses. Adolescents (N = 525; 93% African American, 55% female) 12-17 years of age awaiting primary care appointments at a Federally Qualified Health Center in Baltimore, Maryland completed the 17-item POSIT substance use/abuse subscale and items from a modified World Mental Health Composite International Diagnostic Interview corresponding to DSM-5 alcohol use disorder (AUD) and cannabis use disorder (CUD). Receiver operating characteristic curves, sensitivities, and specificities were examined with DSM-5 AUD, CUD, and a diagnosis of either or both disorders for the standard and revised subscales using risk cutoffs of either 1 or 2 POSIT "yes" responses. For the 17-item subscale, sensitivities were generally high using either cutoff (range: 0.79-1.00), although a cutoff of 1 was superior (sensitivities were 1.00 for AUD, CUD, and for either disorder). Specificities were also high using either cutoff (range: 0.81-0.95) but were higher using a cutoff of 2. For the 11-item subscale, a cutoff of 1 yielded higher sensitivities than a cutoff of 2 (ranges for 1 and 2: 0.96-1.00 and 0.79-0.86, respectively). Specificities for this subscale were higher using a cutoff of 2 (ranges for 1 and 2: 0.82-0.89 and 0.89-0.96, respectively). Findings suggest that the POSIT's substance use/abuse subscale is a potentially useful tool for screening adolescents in primary care for AUD or CUD using a cutoff of 1 or 2. The briefer, revised subscale may be preferable to the standard subscale in

  6. Improving reliability of pQCT-derived muscle area and density measures using a watershed algorithm for muscle and fat segmentation.

    Science.gov (United States)

    Wong, Andy Kin On; Hummel, Kayla; Moore, Cameron; Beattie, Karen A; Shaker, Sami; Craven, B Catharine; Adachi, Jonathan D; Papaioannou, Alexandra; Giangregorio, Lora

    2015-01-01

    In peripheral quantitative computed tomography scans of the calf muscles, segmentation of muscles from subcutaneous fat is challenged by muscle fat infiltration. Threshold-based edge detection segmentation by manufacturer software fails when muscle boundaries are not smooth. This study compared the test-retest precision error for muscle-fat segmentation using the threshold-based edge detection method vs manual segmentation guided by the watershed algorithm. Three clinical populations were investigated: younger adults, older adults, and adults with spinal cord injury (SCI). The watershed segmentation method yielded lower precision error (1.18%-2.01%) and higher (pmuscle density values (70.2±9.2 mg/cm3) compared with threshold-based edge detection segmentation (1.77%-4.06% error, 67.4±10.3 mg/cm3). This was particularly true for adults with SCI (precision error improved by 1.56% and 2.64% for muscle area and density, respectively). However, both methods still provided acceptable precision with error well under 5%. Bland-Altman analyses showed that the major discrepancies between the segmentation methods were found mostly among participants with SCI where more muscle fat infiltration was present. When examining a population where fatty infiltration into muscle is expected, the watershed algorithm is recommended for muscle density and area measurement to enable the detection of smaller change effect sizes. Copyright © 2015 The International Society for Clinical Densitometry. Published by Elsevier Inc. All rights reserved.

  7. Reliability and responsiveness of the Movement Assessment Battery for Children-Second Edition Test in children with developmental coordination disorder.

    Science.gov (United States)

    Wuang, Yee-Pay; Su, Jui-Hsing; Su, Chwen-Yng

    2012-02-01

    To examine the internal consistency, test-retest reliability, and responsiveness of the Movement Assessment Battery for Children-Second Edition (MABC-2) Test for children with developmental coordination disorder (DCD). One hundred and forty-four Taiwanese children with DCD aged 6 to 12 years (87 males, 57 females) were tested on three separate occasions: two baseline measurements with a 20-day interval before the intervention, and a follow-up measurement after 6 months of rehabilitation. The therapists rated the performance of children in school-related physical tasks at baseline and after intervention. Internal consistency for the MABC-2 Test was α = 0.90. Test-retest reliability for the total score was excellent, with an intraclass correlation coefficient of 0.97. A small to medium magnitude of treatment effect was captured by the MABC-2 Test. The minimal detectable change (MDC) was 0.28 points whereas the minimal important difference (MID) values were from 2.36 to 2.50. All subscales except balance showed acceptable validity in differentiating groups of children whose physical performance had improved or remained stable. The MABC-2 Test is a reliable and valid measure to assess motor competence in children with DCD. The MID and MDC scores provide the reference point for clinical decision-making in managing the individual child. © The Authors. Developmental Medicine & Child Neurology © 2012 Mac Keith Press.

  8. Reliable Design Versus Trust

    Science.gov (United States)

    Berg, Melanie; LaBel, Kenneth A.

    2016-01-01

    This presentation focuses on reliability and trust for the users portion of the FPGA design flow. It is assumed that the manufacturer prior to hand-off to the user tests FPGA internal components. The objective is to present the challenges of creating reliable and trusted designs. The following will be addressed: What makes a design vulnerable to functional flaws (reliability) or attackers (trust)? What are the challenges for verifying a reliable design versus a trusted design?

  9. The establishment of evidence-based practice competencies for practicing registered nurses and advanced practice nurses in real-world clinical settings: proficiencies to improve healthcare quality, reliability, patient outcomes, and costs.

    Science.gov (United States)

    Melnyk, Bernadette Mazurek; Gallagher-Ford, Lynn; Long, Lisa English; Fineout-Overholt, Ellen

    2014-02-01

    Although it is widely known that evidence-based practice (EBP) improves healthcare quality, reliability, and patient outcomes as well as reduces variations in care and costs, it is still not the standard of care delivered by practicing clinicians across the globe. Adoption of specific EBP competencies for nurses and advanced practice nurses (APNs) who practice in real-world healthcare settings can assist institutions in achieving high-value, low-cost evidence-based health care. The aim of this study was to develop a set of clear EBP competencies for both practicing registered nurses and APNs in clinical settings that can be used by healthcare institutions in their quest to achieve high performing systems that consistently implement and sustain EBP. Seven national EBP leaders developed an initial set of competencies for practicing registered nurses and APNs through a consensus building process. Next, a Delphi survey was conducted with 80 EBP mentors across the United States to determine consensus and clarity around the competencies. Two rounds of the Delphi survey resulted in total consensus by the EBP mentors, resulting in a final set of 13 competencies for practicing registered nurses and 11 additional competencies for APNs. Incorporation of these competencies into healthcare system expectations, orientations, job descriptions, performance appraisals, and clinical ladder promotion processes could drive higher quality, reliability, and consistency of healthcare as well as reduce costs. Research is now needed to develop valid and reliable tools for assessing these competencies as well as linking them to clinician and patient outcomes. © 2014 Sigma Theta Tau International.

  10. Principles of Bridge Reliability

    DEFF Research Database (Denmark)

    Thoft-Christensen, Palle; Nowak, Andrzej S.

    The paper gives a brief introduction to the basic principles of structural reliability theory and its application to bridge engineering. Fundamental concepts like failure probability and reliability index are introduced. Ultimate as well as serviceability limit states for bridges are formulated......, and as an example the reliability profile and a sensitivity analyses for a corroded reinforced concrete bridge is shown....

  11. Integrated system reliability analysis

    DEFF Research Database (Denmark)

    Gintautas, Tomas; Sørensen, John Dalsgaard

    Specific targets: 1) The report shall describe the state of the art of reliability and risk-based assessment of wind turbine components. 2) Development of methodology for reliability and risk-based assessment of the wind turbine at system level. 3) Describe quantitative and qualitative measures...... (indicators) that can be used to assess the reliability of innovations and new technologies....

  12. Power system reliability

    Energy Technology Data Exchange (ETDEWEB)

    Allan, R.; Billinton, Roy (Manchester Univ. (United Kingdom). Inst. of Science and Technology Saskatchewan Univ., Saskatoon, SK (Canada))

    1994-01-01

    The function of an electric power system is to satisfy the system load as economically as possible and with a reasonable assurance of continuity or reliability. The application of quantitative reliability techniques in planning and operation has increased considerably in the past few years. Reliability evaluation is now becoming an integral part of the economic comparison of alternatives (6 figures, 17 references) (Author)

  13. Botulinum toxin improves quality of life in hemifacial spasm: validation of a questionnaire (HFS-30).

    Science.gov (United States)

    Tan, Eng-King; Fook-Chong, Stephanie; Lum, Sau-Ying; Lim, Erle

    2004-04-15

    Hemifacial spasm (HFS) can be disabling and affect quality of life. There is a lack of a validated scale for evaluating botulinum toxin (BTX) response in HFS. We examined the validity and reliability of a self-rating health-related quality of life (HRQOL) questionnaire (HFS-30) in HFS and investigated the correlation of this questionnaire with the neurologists' assessment of severity of HFS and response to botulinum toxin (BTX) treatment. HFS patients were asked to answer a total of 30 self-rating questions divided into seven subscales: Mobility; Activities of Daily Living (ADL); Emotional Well-being; Stigma; Social support; Cognition; and Communication. All of the items were scored on a 5-point scales ranging from 0 ("never") to 4 ("always"). They were also asked to assess their response to the BTX treatment based on a similar questionnaire at 6-8 weeks after BTX. The validity, reliability and sensitivity of the questionnaire were analyzed statistically. There were 80 HFS patients with mean age of 56.3+/-11.1 (S.D.) years (range 35 to 81), consisting of 54 (67.5%) females, 26 (32.5%) males. The intraclass correlation coefficient (ICC) and Cronbach's alpha were more than 0.7 for the majority of the items and subscales, respectively. There was a good positive correlation of severity of HFS with the subscale scores. Regression analysis of physicians' assessment of response to BTX on change in scores from baseline as rated by patients demonstrated a significant correlation. We demonstrated validity, reliability and sensitivity of the HFS-30 questionnaire. BTX improves quality of life in HFS.

  14. Reliability and radiation effects in compound semiconductors

    CERN Document Server

    Johnston, Allan

    2010-01-01

    This book discusses reliability and radiation effects in compound semiconductors, which have evolved rapidly during the last 15 years. Johnston's perspective in the book focuses on high-reliability applications in space, but his discussion of reliability is applicable to high reliability terrestrial applications as well. The book is important because there are new reliability mechanisms present in compound semiconductors that have produced a great deal of confusion. They are complex, and appear to be major stumbling blocks in the application of these types of devices. Many of the reliability problems that were prominent research topics five to ten years ago have been solved, and the reliability of many of these devices has been improved to the level where they can be used for ten years or more with low failure rates. There is also considerable confusion about the way that space radiation affects compound semiconductors. Some optoelectronic devices are so sensitive to damage in space that they are very difficu...

  15. Reliability of Power Electronic Converter Systems

    DEFF Research Database (Denmark)

    for advancing the reliability, availability, system robustness, and maintainability of PECS at different levels of complexity. Drawing on the experience of an international team of experts, this book explores the reliability of PECS covering topics including an introduction to reliability engineering in power...... electronic converter systems; anomaly detection and remaining-life prediction for power electronics; reliability of DC-link capacitors in power electronic converters; reliability of power electronics packaging; modeling for life-time prediction of power semiconductor modules; minimization of DC......-link capacitance in power electronic converter systems; wind turbine systems; smart control strategies for improved reliability of power electronics system; lifetime modelling; power module lifetime test and state monitoring; tools for performance and reliability analysis of power electronics systems; fault...

  16. The prosthesis evaluation questionnaire: reliability and cross-validation of the Turkish version

    Science.gov (United States)

    Safer, Vildan Binay; Yavuzer, Gunes; Demir, Sibel Ozbudak; Yanikoglu, Inci; Guneri, Fulya Demircioglu

    2015-01-01

    [Purpose] Currently, there are a limited number of amputee-specific instruments for measuring prosthesis-related quality of life with good psychometric properties in Turkey. This study translated the Prosthetic Evaluation Questionnaire to Turkish and analyzed as well as discussed its construct validity and internal consistency. [Subjects and Methods] The Prosthetic Evaluation Questionnaire was adapted for use in Turkish by forward/backward translation. The final Turkish version of this questionnaire was administered to 90 unilateral amputee patients. Second evaluation was possible in 83 participants within a median 28 day time period. [Results] Point estimates for the intraclass correlation coefficient ranged from 0.69 to 0.89 for all 9 Prosthetic Evaluation Questionnaire scales, indicating good correlation. Overall Cronbach’s alpha coefficients ranged from 0.64 to 0.92, except for the perceived response subscale of 0.39. The ambulation subscale was correlated with the physical functioning subscales of Short Form-36 (SF-36) (r=0.48). The social burden subscale score of the Prosthetic Evaluation Questionnaire was correlated with social functioning subscales of SF-36 (r= 0.63). [Conclusion] The Turkish version of the Prosthetic Evaluation Questionnaire is a valid and reliable tool for implementation in the Turkish unilateral amputee population. PMID:26180296

  17. Reliability Characteristics of Power Plants

    Directory of Open Access Journals (Sweden)

    Zbynek Martinek

    2017-01-01

    Full Text Available This paper describes the phenomenon of reliability of power plants. It gives an explanation of the terms connected with this topic as their proper understanding is important for understanding the relations and equations which model the possible real situations. The reliability phenomenon is analysed using both the exponential distribution and the Weibull distribution. The results of our analysis are specific equations giving information about the characteristics of the power plants, the mean time of operations and the probability of failure-free operation. Equations solved for the Weibull distribution respect the failures as well as the actual operating hours. Thanks to our results, we are able to create a model of dynamic reliability for prediction of future states. It can be useful for improving the current situation of the unit as well as for creating the optimal plan of maintenance and thus have an impact on the overall economics of the operation of these power plants.

  18. Reliability Based Ship Structural Design

    DEFF Research Database (Denmark)

    Dogliani, M.; Østergaard, C.; Parmentier, G.

    1996-01-01

    This paper deals with the development of different methods that allow the reliability-based design of ship structures to be transferred from the area of research to the systematic application in current design. It summarises the achievements of a three-year collaborative research project dealing...... with developments of models of load effects and of structural collapse adopted in reliability formulations which aim at calibrating partial safety factors for ship structural design. New probabilistic models of still-water load effects are developed both for tankers and for containerships. New results are presented...... of non-linear wave induced load effects and the corresponding long-term formulations. Methods to combine linear and non-linear components of wave induced load effects have been developed and checked by alternative methods.These improved models were used for the reliability assessment of the primary hull...

  19. The Movement Imagery Questionnaire-Revised, Second Edition (MIQ-RS Is a Reliable and Valid Tool for Evaluating Motor Imagery in Stroke Populations

    Directory of Open Access Journals (Sweden)

    Andrew J. Butler

    2012-01-01

    Full Text Available Mental imagery can improve motor performance in stroke populations when combined with physical therapy. Valid and reliable instruments to evaluate the imagery ability of stroke survivors are needed to maximize the benefits of mental imagery therapy. The purposes of this study were to: examine and compare the test-retest intra-rate reliability of the Movement Imagery Questionnaire-Revised, Second Edition (MIQ-RS in stroke survivors and able-bodied controls, examine internal consistency of the visual and kinesthetic items of the MIQ-RS, determine if the MIQ-RS includes both the visual and kinesthetic dimensions of mental imagery, correlate impairment and motor imagery scores, and investigate the criterion validity of the MIQ-RS in stroke survivors by comparing the results to the KVIQ-10. Test-retest analysis indicated good levels of reliability (ICC range: .83–.99 and internal consistency (Cronbach α: .95–.98 of the visual and kinesthetic subscales in both groups. The two-factor structure of the MIQ-RS was supported by factor analysis, with the visual and kinesthetic components accounting for 88.6% and 83.4% of the total variance in the able-bodied and stroke groups, respectively. The MIQ-RS is a valid and reliable instrument in the stroke population examined and able-bodied populations and therefore useful as an outcome measure for motor imagery ability.

  20. Confirmatory Factor Analysis and Multiple Linear Regression of the Neck Disability Index: Assessment If Subscales Are Equally Relevant in Whiplash and Nonspecific Neck Pain.

    Science.gov (United States)

    Croft, Arthur C; Milam, Bryce; Meylor, Jade; Manning, Richard

    2016-06-01

    Because of previously published recommendations to modify the Neck Disability Index (NDI), we evaluated the responsiveness and dimensionality of the NDI within a population of adult whiplash-injured subjects. The purpose of the present study was to evaluate the responsiveness and dimensionality of the NDI within a population of adult whiplash-injured subjects. Subjects who had sustained whiplash injuries of grade 2 or higher completed an NDI questionnaire. There were 123 subjects (55% female, of which 36% had recovered and 64% had chronic symptoms. NDI subscales were analyzed using confirmatory factor analysis, considering only the subscales and, secondly, using sex as an 11th variable. The subscales were also tested with multiple linear regression modeling using the total score as a target variable. When considering only the 10 NDI subscales, only a single factor emerged, with an eigenvalue of 5.4, explaining 53.7% of the total variance. Strong correlation (> .55) (P Multiple linear regression modeling revealed high internal consistency with all coefficients reaching significance (P < .0001). The 4 NDI subscales exerting the greatest effect were, in decreasing order, Sleeping, Lifting, Headaches, and Pain Intensity. A 2-factor model of the NDI is not justified based on our results, and in this population of whiplash subjects, the NDI was unidimensional, demonstrating high internal consistency and supporting the original validation study of Vernon and Mior.

  1. The Neonatal Pain, Agitation and Sedation Scale reliably detected oversedation but failed to differentiate between other sedation levels.

    Science.gov (United States)

    Giordano, V; Deindl, P; Kuttner, S; Waldhör, T; Berger, A; Olischar, M

    2014-12-01

    The aim of this study was to analyse the sedation subscale of the Neonatal Pain, Agitation and Sedation Scale (N-PASS), because the N-PASS has only been validated for the assessment of acute and prolonged pain. The nurses' expert opinion regarding the level of sedation of the study patients was used as reference scale. Paired assessments of both the N-PASS sedation subscale and the nurses' expert opinion were performed in 50 sedated neonates from 23 to 44 weeks of postmenstrual age. A total set of 503 paired observations was included into analysis. The median N-PASS sedation subscale scores were significantly different for the three nurses' expert opinion categories, with minus eight for oversedation, minus two for adequate sedation and zero for undersedation (p sedation subscale was excellent - linearly weighted Cohen's Kappa was 0.93 - as was the internal consistency of 0.88, estimated by a Cronbach's alpha. The internal consistency increased to 0.90 if the vital sign item of the subscale was deleted. The N-PASS sedation subscale reliably detected oversedation, but failed to differentiate between adequate and undersedation. We therefore recommend using additional methods to ensure adequate assessment of sedation in neonates. ©2014 Foundation Acta Paediatrica. Published by John Wiley & Sons Ltd.

  2. Measuring teacher regulating activities concerning student learning in secondary education classrooms : Reliability and validity of student perceptions

    NARCIS (Netherlands)

    van Beek, J. A.; de Jong, F. P. C. M.; Wubbels, Th.; Minnaert, A. E. M. G.

    2014-01-01

    This article describes the use and validation of the Pedagogical Practices Inventory, which uses student perceptions arranged into five subscales to measure teacher activities concerning the regulation of student learning in secondary education. To determine the reliability and validity of the

  3. The Screening Test for Emotional Problems--Teacher-Report Version (Step-T): Studies of Reliability and Validity

    Science.gov (United States)

    Erford, Bradley T.; Butler, Caitlin; Peacock, Elizabeth

    2015-01-01

    The Screening Test for Emotional Problems-Teacher Version (STEP-T) was designed to identify students aged 7-17 years with wide-ranging emotional disturbances. Coefficients alpha and test-retest reliability were adequate for all subscales except Anxiety. The hypothesized five-factor model fit the data very well and external aspects of validity were…

  4. Orofacial Pain during Mastication in People with Dementia: Reliability Testing of the Orofacial Pain Scale for Non-Verbal Individuals

    NARCIS (Netherlands)

    Vries, M.W. de; Visscher, C.; Delwel, S.; Steen, J.T. van der; Pieper, M.J.; Scherder, E.J.; Achterberg, W.P.; Lobbezoo, F.

    2016-01-01

    Objectives. The aim of this study was to establish the reliability of the "chewing" subscale of the OPS-NVI, a novel tool designed to estimate presence and severity of orofacial pain in nonverbal patients. Methods. The OPS-NVI consists of 16 items for observed behavior, classified into four

  5. Orofacial pain during mastication in people with dementia : Reliability testing of the orofacial pain scale for non-verbal individuals

    NARCIS (Netherlands)

    de Vries, M.W.; Visscher, C.; Delwel, S.; van der Steen, J.T.; Pieper, M.J.C.; Scherder, E.J.A.; Achterberg, W.P.; Lobbezoo, F.

    2016-01-01

    Objectives. The aim of this study was to establish the reliability of the “chewing” subscale of the OPS-NVI, a novel tool designed to estimate presence and severity of orofacial pain in nonverbal patients. Methods. The OPS-NVI consists of 16 items for observed behavior, classified into four

  6. Reliability and validity of the Treatment Satisfaction Questionnaire for Medication among Portuguese-speaking Brazilian patients with hypertension.

    Science.gov (United States)

    Sauer Liberato, Ana Carolina; Cunha Matheus Rodrigues, Roberta; Kim, MyoungJin; Mallory, Caroline

    2016-07-01

    This study examined the reliability and validity of the Brazilian Portuguese version of the Treatment Satisfaction Questionnaire for Medication (version 1.4) among patients with hypertension. Understanding the patient experience with treatment satisfaction will contribute to improved medication adherence and control of hypertension. Hypertension is a serious problem in Brazil that is associated with chronic illness controlled, in part, by consistent adherence to medications. Patient satisfaction with medication treatment is associated with adherence to medication. The Treatment Satisfaction Questionnaire for Medication (version 1.4) is a promising instrument for measuring medication; however, to date there has been no report of the reliability and validity of the instrument with Portuguese-speaking adults with hypertension in Brazil. Cross-sectional descriptive exploratory study. A convenience sample of 300 patients with hypertension in an outpatient setting in the southeast region of São Paulo state in Brazil completed the Treatment Satisfaction Questionnaire for Medication (version 1.4). The instrument, comprised of four subscales, was evaluated for reliability using correlation analyses and internal consistency. Confirmatory factor analysis was used to determine factorial validity. Correlational analyses, internal consistency (Cronbach's alpha) and hierarchical confirmatory factor analysis demonstrate adequate support for the four-factor dimensionality, reliability and factorial validity of the Treatment Satisfaction Questionnaire for Medication (version 1.4). This study provides modest evidence for internal consistency and factorial validity of the Treatment Satisfaction Questionnaire for Medication (version 1.4) in Portuguese-speaking adult Brazilians with hypertension. Future testing should focus on extending reliability testing, discriminant validity and potential translation and literacy issues in this population. Within known limitations, clinicians will

  7. [Measuring workplace climate: reliability and validity of the 12-item Organizational Climate Scale (OCS-12)].

    Science.gov (United States)

    Fukui, Satoe; Haratani, Takashi; Toshima, Yutaka; Shima, Satoru; Takahashi, Masaya; Nakata, Akinori; Fukasawa, Kenji; Ohba, Sayo; Sato, Emi; Hirota, Yasuko

    2004-11-01

    In order to investigate the reliability and validity of the short version of the 30-item Organizational Climate Scale (OCS-30; Toshima and Matsuda, 1992, 1995), a self-administered questionnaire was conducted in a sample of 819 employees of two medium-sized private companies in Japan by using the OCS-30, the Generic Job Stress Questionnaire (GJSQ), and the 12-item General Health Questionnaire (GHQ-12). The OCS has two subscales, i.e., the Tradition Scale (TS) and the Organizational Environment Scale (OES). The organizational climate perceived by each worker can be grouped into four categories based on the subscale scores: low TS and high OES (Active), high TS and high OES (Governed), low TS and low OES (Disorganized), and high TS and low OES (Reluctant). Principal component analysis for the OCS-30 was submitted (varimax rotation, the number of factors = 2), and 6 items for each factor, with factor loadings greater than 0.50, were selected for the short version, which constituted the 12-item Organizational Climate Scale (OCS-12). Cronbach's alpha reliability coefficients of the two subscales of the OCS-12 were acceptable; 0.63 for the TS and 0.71 for the OES. Both two subscales of the OCS-12 were significantly correlated with the GHQ-12 and many subscales of the GJSQ, which indicated the good constructive validity of the OCS-12. Among 4 types of organizational climate categorized by the OCS-12, the "Active" group showed the lowest job stress scores. It is suggested that the OCS-12 could be a reliable and valid instrument for assessing workers' perception of workplace climate.

  8. Self-stigma of mental illness scale--short form: reliability and validity.

    Science.gov (United States)

    Corrigan, Patrick W; Michaels, Patrick J; Vega, Eduardo; Gause, Michael; Watson, Amy C; Rüsch, Nicolas

    2012-08-30

    The internalization of public stigma by persons with serious mental illnesses may lead to self-stigma, which harms self-esteem, self-efficacy, and empowerment. Previous research has evaluated a hierarchical model that distinguishes among stereotype awareness, agreement, application to self, and harm to self with the 40-item Self-Stigma of Mental Illness Scale (SSMIS). This study addressed SSMIS critiques (too long, contains offensive items that discourages test completion) by strategically omitting half of the original scale's items. Here we report reliability and validity of the 20-item short form (SSMIS-SF) based on data from three previous studies. Retained items were rated less offensive by a sample of consumers. Results indicated adequate internal consistencies for each subscale. Repeated measures ANOVAs showed subscale means progressively diminished from awareness to harm. In support of its validity, the harm subscale was found to be inversely and significantly related to self-esteem, self-efficacy, empowerment, and hope. After controlling for level of depression, these relationships remained significant with the exception of the relation between empowerment and harm SSMIS-SF subscale. Future research with the SSMIS-SF should evaluate its sensitivity to change and its stability through test-rest reliability. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

  9. Psychometric Assessment of the PPDG: Utilizing Cronbach’s Alpha as a Means of Reliability

    Directory of Open Access Journals (Sweden)

    Joe R. Anderson, Pharm. D.

    2013-01-01

    Full Text Available Introduction: Since the development of the 10 item Purdue Pharmacist Directive Guidance (PPDG Scale several studies of the psychometric properties of the PPDG have been conducted. Although Cronbach’s alpha was calculated as a means of internal consistency reliability, a demonstration of the mean centering of the individual items from the instrument were not explored.Objectives: This study focused on investigating the mean stabilization of items within the PPDG as they pertain to Cronbach’s reliability coefficient calculation.Methods:Using item analysis procedures in SPSS, the mean stability of items within the general factor of directive guidance and subscales of instruction and feedback and goal setting were examined for the PPDG.Results:Mean stability scores for entire PPDG scale and the subscales of instruction and feedback and goal setting were strong. Also, corrected item-total correlations and Cronbach’s alphas following item deletion were good for the overall PPDG scale and the subscales.Conclusions: The results provide evidence to enhance understanding of the psychometric stability of the PPDG scale and its subscales.

  10. Reliability and safety engineering

    CERN Document Server

    Verma, Ajit Kumar; Karanki, Durga Rao

    2016-01-01

    Reliability and safety are core issues that must be addressed throughout the life cycle of engineering systems. Reliability and Safety Engineering presents an overview of the basic concepts, together with simple and practical illustrations. The authors present reliability terminology in various engineering fields, viz.,electronics engineering, software engineering, mechanical engineering, structural engineering and power systems engineering. The book describes the latest applications in the area of probabilistic safety assessment, such as technical specification optimization, risk monitoring and risk informed in-service inspection. Reliability and safety studies must, inevitably, deal with uncertainty, so the book includes uncertainty propagation methods: Monte Carlo simulation, fuzzy arithmetic, Dempster-Shafer theory and probability bounds. Reliability and Safety Engineering also highlights advances in system reliability and safety assessment including dynamic system modeling and uncertainty management. Cas...

  11. Clinical utility of the MMPI-A content scales and Harris-Lingoes subscales in the assessment of suicidal risk factors in psychiatric adolescents.

    Science.gov (United States)

    Kopper, B A; Osman, A; Osman, J R; Hoffman, J

    1998-02-01

    This study of 143 inpatient adolescents (68 boys and 75 girls) investigated the clinical utility of the MMPI-A in assessing suicidal risk factors by examining the unique contribution of the content scales and Harris-Lingoes subscales beyond what is provided by the basic clinical scales. The results of the regression analyses indicated that for boys, the Depression, Psychopathic Deviate and Hypomania scales; Alienation and Anxiety content scales: and Subjective Depression. Self Alienation, Imperturbability, and Amorality Harris-Lingoes subscales contributed significantly to the prediction of suicide probability. For girls, the Depression, Psychopathic Deviate, and Hypomania scales; Family Problems, Conduct Problems, School Problems, Depression, and Social Discomfort content scales; and the Subjective Depression, Self Alienation, Psychomotor Acceleration, and Imperturbability Harris-Lingoes subscales contributed significantly to the prediction of suicide probability.

  12. Improvements To Micro Contact Performance And Reliability

    Science.gov (United States)

    2016-12-22

    for their use in other microelectronic de- vices [98]. Thus, the use of carbon-based conducting materials such as graphene may protect metals which...manifesting in specific directions within the reciprocal space of some semiconductors [120, 121], and are even in use currently within ballistic diodes that...effective negative mass under reasonable operating con- ditions, it will likely be incorporated in typical semiconductor fabrication processes. A small

  13. The X-40 sub-scale technology demonstrator and its U.S. Army CH-47 Chinook helicopter mothership fly

    Science.gov (United States)

    2000-01-01

    The X-40 sub-scale technology demonstrator and its U.S. Army CH-47 Chinook helicopter mothership fly over a dry lakebed runway during a captive-carry test flight from NASA's Dryden Flight Research Center, Edwards, California. The X-40 is attached to a sling which is suspended from the CH-47 by a 110-foot-long cable during the tests, while a small parachute trails behind to provide stability. The captive carry flights are designed to verify the X-40's navigation and control systems, rigging angles for its sling, and stability and control of the helicopter while carrying the X-40 on a tether. Following a series of captive-carry flights, the X-40 made free flights from a launch altitude of about 15,000 feet above ground, gliding to a fully autonomous landing. The X-40 is an unpowered 82 percent scale version of the X-37, a Boeing-developed spaceplane designed to demonstrate various advanced technologies for development of future lower-cost access to space vehicles. The X-37 will be carried into space aboard a space shuttle and then released to perform various maneuvers and a controlled re-entry through the Earth's atmosphere to an airplane-style landing on a runway, controlled entirely by pre-programmed computer software.

  14. Development of a sub-scale dynamics model for pressure relaxation of multi-material cells in Lagrangian hydrodynamics

    Directory of Open Access Journals (Sweden)

    Canfield T.R.

    2011-01-01

    Full Text Available We have extended the Sub-Scale Dynamics (SSD closure model for multi-fluid computational cells. Volume exchange between two materials is based on the interface area and a notional interface translation velocity, which is derived from a linearized Riemann solution. We have extended the model to cells with any number of materials, computing pressure-difference-driven volume and energy exchange as the algebraic sum of pairwise interactions. In multiple dimensions, we rely on interface reconstruction to provide interface areas and orientations, and centroids of material polygons. In order to prevent unphysically large or unmanageably small material volumes, we have used a flux-corrected transport (FCT approach to limit the pressure-driven part of the volume exchange. We describe the implementation of this model in two dimensions in the FLAG hydrodynamics code. We also report on Lagrangian test calculations, comparing them with others made using a mixed-zone closure model due to Tipton, and with corresponding calculations made with only single-material cells. We find that in some cases, the SSD model more accurately predicts the state of material in mixed cells. By comparing the algebraic forms of both models, we identify similar dependencies on state and dynamical variables, and propose explanations for the apparent higher fidelity of the SSD model.

  15. Psychometric properties of the existence subscale of the purpose in life questionnaire for Chinese adolescents in Hong Kong.

    Science.gov (United States)

    Law, Ben M F

    2012-01-01

    The current study aims to test the psychometric properties of the Existence Subscale of the Purpose in Life Questionnaire (EPIL) for early adolescence. The Purpose in Life Questionnaire (PIL), originally created by Craumbaugh and Maholick, is a 20-item scale measuring different dimensions of life purposes. The current study selected seven items representative of the existence dimension to form another scale, the EPIL. The analysis was based on 2842 early adolescents, ranging from 11 to 14 years old. Principal axis factoring found one factor, with 60% variance being explained. Cronbach's alpha for the EPIL was 0.89, which was high. The factor structure was stable across genders. Criterion-related validity was determined when the scale was used to differentiate volunteers and nonvolunteers. Construct validity was found when the scale was associated with life satisfaction. The results give support to the fact that the EPIL could be used alone to measure the psychological well-being of early adolescents and the appropriateness of the EPIL in adolescent research.

  16. Space Launch System Base Heating Test: Sub-Scale Rocket Engine/Motor Design, Development and Performance Analysis

    Science.gov (United States)

    Mehta, Manish; Seaford, Mark; Kovarik, Brian; Dufrene, Aaron; Solly, Nathan; Kirchner, Robert; Engel, Carl D.

    2014-01-01

    The Space Launch System (SLS) base heating test is broken down into two test programs: (1) Pathfinder and (2) Main Test. The Pathfinder Test Program focuses on the design, development, hot-fire test and performance analyses of the 2% sub-scale SLS core-stage and booster element propulsion systems. The core-stage propulsion system is composed of four gaseous oxygen/hydrogen RS-25D model engines and the booster element is composed of two aluminum-based model solid rocket motors (SRMs). The first section of the paper discusses the motivation and test facility specifications for the test program. The second section briefly investigates the internal flow path of the design. The third section briefly shows the performance of the model RS-25D engines and SRMs for the conducted short duration hot-fire tests. Good agreement is observed based on design prediction analysis and test data. This program is a challenging research and development effort that has not been attempted in 40+ years for a NASA vehicle.

  17. Analysis of the laser ignition of methane/oxygen mixtures in a sub-scale rocket combustion chamber

    Science.gov (United States)

    Wohlhüter, Michael; Zhukov, Victor P.; Sender, Joachim; Schlechtriem, Stefan

    2017-06-01

    The laser ignition of methane/oxygen mixtures in a sub-scale rocket combustion chamber has been investigated numerically and experimentally. The ignition test case used in the present paper was generated during the In-Space Propulsion project (ISP-1), a project focused on the operation of propulsion systems in space, the handling of long idle periods between operations, and multiple reignitions under space conditions. Regarding the definition of the numerical simulation and the suitable domain for the current model, 2D and 3D simulations have been performed. Analysis shows that the usage of a 2D geometry is not suitable for this type of simulation, as the reduction of the geometry to a 2D domain significantly changes the conditions at the time of ignition and subsequently the flame development. The comparison of the numerical and experimental results shows a strong discrepancy in the pressure evolution and the combustion chamber pressure peak following the laser spark. The detailed analysis of the optical Schlieren and OH data leads to the conclusion that the pressure measurement system was not able to capture the strong pressure increase and the peak value in the combustion chamber during ignition. Although the timing in flame development following the laser spark is not captured appropriately, the 3D simulations reproduce the general ignition phenomena observed in the optical measurement systems, such as pressure evolution and injector flow characteristics.

  18. Development of a sub-scale dynamics model for pressure relaxation of multi-material cells in Lagrangian hydrodynamics

    Energy Technology Data Exchange (ETDEWEB)

    Harrison, Alan K [Los Alamos National Laboratory; Shashkov, Mikhail J [Los Alamos National Laboratory; Fung, Jimmy [Los Alamos National Laboratory; Canfield, Thomas R [Los Alamos National Laboratory; Kamm, James R [SNLA

    2010-10-14

    We have extended the Sub-Scale Dynamics (SSD) closure model for multi-fluid computational cells. Volume exchange between two materials is based on the interface area and a notional interface translation velocity, which is derived from a linearized Riemann solution. We have extended the model to cells with any number of materials, computing pressure-difference-driven volume and energy exchange as the algebraic sum of pairwise interactions. In multiple dimensions, we rely on interface reconstruction to provide interface areas and orientations, and centroids of material polygons. In order to prevent unphysically large or unmanageably small material volumes, we have used a flux-corrected transport (FCT) approach to limit the pressure-driven part of the volume exchange. We describe the implementation of this model in two dimensions in the FLAG hydrodynamics code. We also report on Lagrangian test calculations, comparing them with others made using a mixed-zone closure model due to Tipton, and with corresponding calculations made with only single-material cells. We find that in some cases, the SSD model more accurately predicts the state of material in mixed cells. By comparing the algebraic forms of both models, we identify similar dependencies on state and dynamical variables, and propose explanations for the apparent higher fidelity of the SSD model.

  19. Structural Reliability Methods

    DEFF Research Database (Denmark)

    Ditlevsen, Ove Dalager; Madsen, H. O.

    The structural reliability methods quantitatively treat the uncertainty of predicting the behaviour and properties of a structure given the uncertain properties of its geometry, materials, and the actions it is supposed to withstand. This book addresses the probabilistic methods for evaluation...... of structural reliability, including the theoretical basis for these methods. Partial safety factor codes under current practice are briefly introduced and discussed. A probabilistic code format for obtaining a formal reliability evaluation system that catches the most essential features of the nature...

  20. Differential Item Functioning in the SF-36 Physical Functioning and Mental Health Sub-Scales: A Population-Based Investigation in the Canadian Multicentre Osteoporosis Study.

    Science.gov (United States)

    Lix, Lisa M; Wu, Xiuyun; Hopman, Wilma; Mayo, Nancy; Sajobi, Tolulope T; Liu, Juxin; Prior, Jerilynn C; Papaioannou, Alexandra; Josse, Robert G; Towheed, Tanveer E; Davison, K Shawn; Sawatzky, Richard

    2016-01-01

    Self-reported health status measures, like the Short Form 36-item Health Survey (SF-36), can provide rich information about the overall health of a population and its components, such as physical, mental, and social health. However, differential item functioning (DIF), which arises when population sub-groups with the same underlying (i.e., latent) level of health have different measured item response probabilities, may compromise the comparability of these measures. The purpose of this study was to test for DIF on the SF-36 physical functioning (PF) and mental health (MH) sub-scale items in a Canadian population-based sample. Study data were from the prospective Canadian Multicentre Osteoporosis Study (CaMos), which collected baseline data in 1996-1997. DIF was tested using a multiple indicators multiple causes (MIMIC) method. Confirmatory factor analysis defined the latent variable measurement model for the item responses and latent variable regression with demographic and health status covariates (i.e., sex, age group, body weight, self-perceived general health) produced estimates of the magnitude of DIF effects. The CaMos cohort consisted of 9423 respondents; 69.4% were female and 51.7% were less than 65 years. Eight of 10 items on the PF sub-scale and four of five items on the MH sub-scale exhibited DIF. Large DIF effects were observed on PF sub-scale items about vigorous and moderate activities, lifting and carrying groceries, walking one block, and bathing or dressing. On the MH sub-scale items, all DIF effects were small or moderate in size. SF-36 PF and MH sub-scale scores were not comparable across population sub-groups defined by demographic and health status variables due to the effects of DIF, although the magnitude of this bias was not large for most items. We recommend testing and adjusting for DIF to ensure comparability of the SF-36 in population-based investigations.

  1. Photovoltaic Module Reliability Workshop 2010: February 18-19, 2010

    Energy Technology Data Exchange (ETDEWEB)

    Kurtz, J.

    2013-11-01

    NREL's Photovoltaic (PV) Module Reliability Workshop (PVMRW) brings together PV reliability experts to share information, leading to the improvement of PV module reliability. Such improvement reduces the cost of solar electricity and promotes investor confidence in the technology--both critical goals for moving PV technologies deeper into the electricity marketplace.

  2. Photovoltaic Module Reliability Workshop 2014: February 25-26, 2014

    Energy Technology Data Exchange (ETDEWEB)

    Kurtz, S.

    2014-02-01

    NREL's Photovoltaic (PV) Module Reliability Workshop (PVMRW) brings together PV reliability experts to share information, leading to the improvement of PV module reliability. Such improvement reduces the cost of solar electricity and promotes investor confidence in the technology--both critical goals for moving PV technologies deeper into the electricity marketplace.

  3. Photovoltaic Module Reliability Workshop 2011: February 16-17, 2011

    Energy Technology Data Exchange (ETDEWEB)

    Kurtz, S.

    2013-11-01

    NREL's Photovoltaic (PV) Module Reliability Workshop (PVMRW) brings together PV reliability experts to share information, leading to the improvement of PV module reliability. Such improvement reduces the cost of solar electricity and promotes investor confidence in the technology--both critical goals for moving PV technologies deeper into the electricity marketplace.

  4. Photovoltaic Module Reliability Workshop 2012: February 28 - March 1, 2012

    Energy Technology Data Exchange (ETDEWEB)

    Kurtz, S.

    2013-11-01

    NREL's Photovoltaic (PV) Module Reliability Workshop (PVMRW) brings together PV reliability experts to share information, leading to the improvement of PV module reliability. Such improvement reduces the cost of solar electricity and promotes investor confidence in the technology--both critical goals for moving PV technologies deeper into the electricity marketplace.

  5. Photovoltaic Module Reliability Workshop 2013: February 26-27, 2013

    Energy Technology Data Exchange (ETDEWEB)

    Kurtz, S.

    2013-10-01

    NREL's Photovoltaic (PV) Module Reliability Workshop (PVMRW) brings together PV reliability experts to share information, leading to the improvement of PV module reliability. Such improvement reduces the cost of solar electricity and promotes investor confidence in the technology--both critical goals for moving PV technologies deeper into the electricity marketplace.

  6. Measurement System Reliability Assessment

    Directory of Open Access Journals (Sweden)

    Kłos Ryszard

    2015-06-01

    Full Text Available Decision-making in problem situations is based on up-to-date and reliable information. A great deal of information is subject to rapid changes, hence it may be outdated or manipulated and enforce erroneous decisions. It is crucial to have the possibility to assess the obtained information. In order to ensure its reliability it is best to obtain it with an own measurement process. In such a case, conducting assessment of measurement system reliability seems to be crucial. The article describes general approach to assessing reliability of measurement systems.

  7. Circuit design for reliability

    CERN Document Server

    Cao, Yu; Wirth, Gilson

    2015-01-01

    This book presents physical understanding, modeling and simulation, on-chip characterization, layout solutions, and design techniques that are effective to enhance the reliability of various circuit units.  The authors provide readers with techniques for state of the art and future technologies, ranging from technology modeling, fault detection and analysis, circuit hardening, and reliability management. Provides comprehensive review on various reliability mechanisms at sub-45nm nodes; Describes practical modeling and characterization techniques for reliability; Includes thorough presentation of robust design techniques for major VLSI design units; Promotes physical understanding with first-principle simulations.

  8. A reliability generalization meta-analysis of coefficient alpha and test-retest coefficient for the aging males' symptoms (AMS) scale.

    Science.gov (United States)

    Lee, Chin-Pang; Chiu, Yu-Wen; Chu, Chun-Lin; Chen, Yu; Jiang, Kun-Hao; Chen, Jiun-Liang; Chen, Ching-Yen

    2016-12-01

    The aging males' symptoms (AMS) scale is an instrument used to determine the health-related quality of life in adult and elderly men. The purpose of this study was to synthesize internal consistency (Cronbach's alpha) and test-retest reliability for the AMS scale and its three subscales. Of the 123 studies reviewed, 12 provided alpha coefficients which were then used in the meta-analyses of internal consistency. Seven of the 12 included studies provided test-retest coefficients, and these were used in the meta-analyses of test-retest reliability. The AMS scale had excellent internal consistency [α = 0.89 (95% CI 0.88-0.90)]; the mean alpha estimates across the AMS subscales ranged from 0.79 to 0.82. The AMS scale also had good test-retest reliability [r = 0.85 (95% CI 0.82-0.88]; the test-retest reliability coefficients of the AMS subscales ranged from 0.76 to 0.83. There was significant heterogeneity among the included studies. The AMS scale and the three subscales had fairly good internal consistency and test-retest reliability. Future psychometric studies of the AMS scale should report important characteristics of the participants, details of item scores, and test-retest reliability.

  9. Establishing monitoring programs for travel time reliability.

    Science.gov (United States)

    2014-01-01

    Within the second Strategic Highway Research Program (SHRP 2), Project L02 focused on creating a suite of methods by which transportation agencies could monitor and evaluate travel time reliability. Creation of the methods also produced an improved u...

  10. Reliability Research for Photovoltaic Modules

    Science.gov (United States)

    Ross, Ronald J., Jr.

    1986-01-01

    Report describes research approach used to improve reliability of photovoltaic modules. Aimed at raising useful module lifetime to 20 to 30 years. Development of cost-effective solutions to module-lifetime problem requires compromises between degradation rates, failure rates, and lifetimes, on one hand, and costs of initial manufacture, maintenance, and lost energy, on other hand. Life-cycle costing integrates disparate economic terms, allowing cost effectiveness to be quantified, allowing comparison of different design alternatives.

  11. Validity and Reliability of Asbestos Knowledge and Awareness Questionnaire for Environmental Asbestos Exposure in Rural Areas

    Directory of Open Access Journals (Sweden)

    Selma Metintaş

    2017-04-01

    Full Text Available Objective: There is no treatment for asbestos–related diseases, but they can be prevented. One of the first interventions is to improve the knowledge level of people in order to protect people from asbestos and asbestos–related diseases. The present study was conducted to develop a questionnaire for measuring the knowledge and awareness level of asbestos and also assess its validity and reliability in a rural population that is exposed to asbestos environmentally. Methods: A questionnaire, interviewer–administered, that included 37 items was employed on a convenient sample consisting of adult persons who attended a tertiary teaching hospital in Eskişehir where asbestos exposure is widespread in its rural areas. After assessment of validity and reliability of the results, the questionnaire was refined to 19 items and one subscale. Results: A total of 760 participants were included in this study. The mean age of participants was 53.2±15.1 years and 51.6% of them were male. The discrimination and difficulty indices of the asbestos knowledge and awareness questionnaire ranged between 20.0–60.5% and 0.39–0.98, respectively. Cronbach’s alpha coefficient was 0.951 for overall items. The median (min–max and mean (SD score of the study population were 30 (19–56 and 33.9 (11.9, respectively. The score increased correspondingly with greater knowledge levels. Conclusion: This questionnaire is a practical and easy tool to apply with acceptable reliability and validity on high-risk adults in rural areas with environmental asbestos exposure.

  12. Reliability Growth in Space Life Support Systems

    Science.gov (United States)

    Jones, Harry W.

    2014-01-01

    A hardware system's failure rate often increases over time due to wear and aging, but not always. Some systems instead show reliability growth, a decreasing failure rate with time, due to effective failure analysis and remedial hardware upgrades. Reliability grows when failure causes are removed by improved design. A mathematical reliability growth model allows the reliability growth rate to be computed from the failure data. The space shuttle was extensively maintained, refurbished, and upgraded after each flight and it experienced significant reliability growth during its operational life. In contrast, the International Space Station (ISS) is much more difficult to maintain and upgrade and its failure rate has been constant over time. The ISS Carbon Dioxide Removal Assembly (CDRA) reliability has slightly decreased. Failures on ISS and with the ISS CDRA continue to be a challenge.

  13. Use of the ICU Nurse-Physician Questionnaire (ICU N-P-Q): testing reliability and validity in neonatal intensive care units in Japan.

    Science.gov (United States)

    Sasaki, Hatoko; Yonemoto, Naohiro; Mori, Rintaro; Nishida, Toshihiko; Kusuda, Satoshi; Nakayama, Takeo

    2016-05-09

    Although communication among health providers has become a critical part of improving quality of care, few studies on this topic have been conducted in Japan. This study aimed to examine the reliability and validity of the Intensive Care Unit Nurse-Physician Questionnaire (ICU N-P-Q) for use among nurses and physicians in neonatal ICUs (NICUs) in Japan. A Japanese translation of the ICU N-P-Q was administered to physicians and nurses working at 40 NICUs across Japan, which were participating in the Improvement of NICU Practice and Team Approach Cluster randomized controlled trial (INTACT). We used the principal components analysis to evaluate the factor structure of the instruments. Convergent validity was assessed by examining correlations between the subscales of Communication and Conflict Management of the ICU N-P-Q and the subscales and total score of the Nurse-Physician Collaboration Scale (NPCS). Correlations between the subscales of Communication and Conflict Management by correlation with scales that refer to performance, including Job Satisfaction and Unit Effectiveness, were calculated to test the criterion validity. In total, 2006 questionnaires were completed by 316 physicians and 1690 nurses. The exploratory factor analysis revealed 15 factors in the physicians' questionnaire and 12 in the nurses' questionnaire. Convergent validity was confirmed, except for 'Between-group Accuracy' and 'Cooperativeness' in the physicians' scale, and for 'Between-group Accuracy' and 'Sharing of Patient Information' in the nurses' scale. Correlations between the subscales of communication and outcomes were confirmed in the nurses' questionnaire but were not fully supported in the physicians' questionnaire. Although the psychometric property behaved somewhat differently by occupation, the present findings provide preliminary support for the utility of the common item structure with the original scale, to measure the degree and quality of communication and collaboration

  14. Reliable design of electronic equipment an engineering guide

    CERN Document Server

    Natarajan, Dhanasekharan

    2014-01-01

    This book explains reliability techniques with examples from electronics design for the benefit of engineers. It presents the application of de-rating, FMEA, overstress analyses and reliability improvement tests for designing reliable electronic equipment. Adequate information is provided for designing computerized reliability database system to support the application of the techniques by designers. Pedantic terms and the associated mathematics of reliability engineering discipline are excluded for the benefit of comprehensiveness and practical applications. This book offers excellent support

  15. System and Software Reliability (C103)

    Science.gov (United States)

    Wallace, Dolores

    2003-01-01

    Within the last decade better reliability models (hardware. software, system) than those currently used have been theorized and developed but not implemented in practice. Previous research on software reliability has shown that while some existing software reliability models are practical, they are no accurate enough. New paradigms of development (e.g. OO) have appeared and associated reliability models have been proposed posed but not investigated. Hardware models have been extensively investigated but not integrated into a system framework. System reliability modeling is the weakest of the three. NASA engineers need better methods and tools to demonstrate that the products meet NASA requirements for reliability measurement. For the new models for the software component of the last decade, there is a great need to bring them into a form that they can be used on software intensive systems. The Statistical Modeling and Estimation of Reliability Functions for Systems (SMERFS'3) tool is an existing vehicle that may be used to incorporate these new modeling advances. Adapting some existing software reliability modeling changes to accommodate major changes in software development technology may also show substantial improvement in prediction accuracy. With some additional research, the next step is to identify and investigate system reliability. System reliability models could then be incorporated in a tool such as SMERFS'3. This tool with better models would greatly add value in assess in GSFC projects.

  16. Structural Reliability Methods

    DEFF Research Database (Denmark)

    Ditlevsen, Ove Dalager; Madsen, H. O.

    of structural reliability, including the theoretical basis for these methods. Partial safety factor codes under current practice are briefly introduced and discussed. A probabilistic code format for obtaining a formal reliability evaluation system that catches the most essential features of the nature...

  17. Hawaii Electric System Reliability

    Energy Technology Data Exchange (ETDEWEB)

    Loose, Verne William [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Silva Monroy, Cesar Augusto [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2012-08-01

    This report addresses Hawaii electric system reliability issues; greater emphasis is placed on short-term reliability but resource adequacy is reviewed in reference to electric consumers’ views of reliability “worth” and the reserve capacity required to deliver that value. The report begins with a description of the Hawaii electric system to the extent permitted by publicly available data. Electrical engineering literature in the area of electric reliability is researched and briefly reviewed. North American Electric Reliability Corporation standards and measures for generation and transmission are reviewed and identified as to their appropriateness for various portions of the electric grid and for application in Hawaii. Analysis of frequency data supplied by the State of Hawaii Public Utilities Commission is presented together with comparison and contrast of performance of each of the systems for two years, 2010 and 2011. Literature tracing the development of reliability economics is reviewed and referenced. A method is explained for integrating system cost with outage cost to determine the optimal resource adequacy given customers’ views of the value contributed by reliable electric supply. The report concludes with findings and recommendations for reliability in the State of Hawaii.

  18. Hawaii electric system reliability.

    Energy Technology Data Exchange (ETDEWEB)

    Silva Monroy, Cesar Augusto; Loose, Verne William

    2012-09-01

    This report addresses Hawaii electric system reliability issues; greater emphasis is placed on short-term reliability but resource adequacy is reviewed in reference to electric consumers' views of reliability %E2%80%9Cworth%E2%80%9D and the reserve capacity required to deliver that value. The report begins with a description of the Hawaii electric system to the extent permitted by publicly available data. Electrical engineering literature in the area of electric reliability is researched and briefly reviewed. North American Electric Reliability Corporation standards and measures for generation and transmission are reviewed and identified as to their appropriateness for various portions of the electric grid and for application in Hawaii. Analysis of frequency data supplied by the State of Hawaii Public Utilities Commission is presented together with comparison and contrast of performance of each of the systems for two years, 2010 and 2011. Literature tracing the development of reliability economics is reviewed and referenced. A method is explained for integrating system cost with outage cost to determine the optimal resource adequacy given customers' views of the value contributed by reliable electric supply. The report concludes with findings and recommendations for reliability in the State of Hawaii.

  19. LED system reliability

    NARCIS (Netherlands)

    Driel, W.D. van; Yuan, C.A.; Koh, S.; Zhang, G.Q.

    2011-01-01

    This paper presents our effort to predict the system reliability of Solid State Lighting (SSL) applications. A SSL system is composed of a LED engine with micro-electronic driver(s) that supplies power to the optic design. Knowledge of system level reliability is not only a challenging scientific

  20. Subscale Carbon-Carbon Nozzle Extension Development and Hot Fire Testing in Support of Upper Stage Liquid Rocket Engines

    Science.gov (United States)

    Gradl, Paul; Valentine, Peter; Crisanti, Matthew; Greene, Sandy Elam

    2016-01-01

    Upper stage and in-space liquid rocket engines are optimized for performance through the use of high area ratio nozzles to fully expand combustion gases to low exit pressures increasing exhaust velocities. Due to the large size of such nozzles and the related engine performance requirements, carbon-carbon (C/C) composite nozzle extensions are being considered for use in order to reduce weight impacts. NASA and industry partner Carbon-Carbon Advanced Technologies (C-CAT) are working towards advancing the technology readiness level of large-scale, domestically-fabricated, C/C nozzle extensions. These C/C extensions have the ability to reduce the overall costs of extensions relative to heritage metallic and composite extensions and to decrease weight by 50%. Material process and coating developments have advanced over the last several years, but hot fire testing to fully evaluate C/C nozzle extensions in relevant environments has been very limited. NASA and C-CAT have designed, fabricated and hot fire tested multiple subscale nozzle extension test articles of various C/C material systems, with the goal of assessing and advancing the manufacturability of these domestically producible materials as well as characterizing their performance when subjected to the typical environments found in a variety of liquid rocket and scramjet engines. Testing at the MSFC Test Stand 115 evaluated heritage and state-of-the-art C/C materials and coatings, demonstrating the capabilities of the high temperature materials and their fabrication methods. This paper discusses the design and fabrication of the 1.2k-lbf sized carbon-carbon nozzle extensions, provides an overview of the test campaign, presents results of the hot fire testing, and discusses potential follow-on development work.

  1. Measurement of aggressive behaviors in dementia: comparison of the physical aggression subscales of the Cohen-Mansfield Agitation Inventory and the Ryden Aggression Scale.

    Science.gov (United States)

    Whall, Ann L; Kim, Hyojeong; Colling, Kathleen Byrne; Hong, Gwi-Ryung; DeCicco, Barry; Antonakos, Cathy

    2013-07-01

    One of the central issues in the development of research-based interventions for aggressive behavior (AB) in late-stage dementia is the provision of precise measurement of the major dependent variable, in this case, AB levels. To advance the nursing goal of evidence-based practice, this article presents the characteristics of two research instruments: the Cohen-Mansfield Agitation Inventory (CMAI) aggressive behavior subscale (CMAI-ABS) and the Ryden Aggression Scale (RAS) physically aggressive behavior subscale (RAS-PABS). A total of 282 shower bath events (which are most associated with AB) were observed for 107 nursing home residents with dementia in nine randomly selected nursing homes. Then, we compared the psychometric properties of the CMAI-ABS and the RAS-PABS. Moderate to substantial agreements between the two instruments were identified using Cohen's Kappa. A similar percentage of AB was found on both subscales. Similar items on both subscales, such as hitting and pushing, were moderately correlated. Overall, the study results support that the CMAI-ABS and RAS-PABS measure a single but multifaceted construct-physically aggressive behavior in dementia. Copyright 2013, SLACK Incorporated.

  2. Complex Relationships Among Masculine Norms and Health/Well-Being Outcomes: Correlation Patterns of the Conformity to Masculine Norms Inventory Subscales.

    Science.gov (United States)

    Gerdes, Zachary T; Levant, Ronald F

    2018-03-01

    The Conformity to Masculine Norms Inventory (CMNI) is a widely used multidimensional scale. Studies using the CMNI most often report only total scale scores, which are predominantly associated with negative outcomes. Various studies since the CMNI's inception in 2003 using subscales have reported both positive and negative outcomes. The current content analysis examined studies ( N = 17) correlating the 11 subscales with 63 criterion variables across 7 categories. Most findings were consistent with past research using total scale scores that reported negative outcomes. For example, conformity to masculine norms has been inversely related to help-seeking and positively correlated with concerning health variables, such as substance use. Nonetheless, past reliance on total scores has obscured the complexity of associations with the CMNI in that 30% of the findings in the present study reflected positive outcomes, particularly for health promotion. Subscales differed in their relationships with various outcomes: for one subscale they were predominantly positive, but six others were mostly negative. The situational and contextual implications of conformity to masculine norms and their relationships to positive and negative outcomes are discussed.

  3. Toward defining a cutoff score for elevated fear of hypoglycemia on the hypoglycemia fear survey worry subscale in patients with type 2 diabetes

    DEFF Research Database (Denmark)

    Hajós, Tibor R S; Polonsky, William H; Pouwer, Frans

    2014-01-01

    OBJECTIVE To determine a cutoff score for clinically meaningful fear of hypoglycemia (FoH) on the Hypoglycemia Fear Survey Worry subscale (HFS-W). RESEARCH DESIGN AND METHODS Data on the HFS-W, history of hypoglycemia, emotional well-being (World Health Organization-5 well-being index...

  4. Structural Reliability Methods

    DEFF Research Database (Denmark)

    Ditlevsen, Ove Dalager; Madsen, H. O.

    The structural reliability methods quantitatively treat the uncertainty of predicting the behaviour and properties of a structure given the uncertain properties of its geometry, materials, and the actions it is supposed to withstand. This book addresses the probabilistic methods for evaluation...... of structural reliability, including the theoretical basis for these methods. Partial safety factor codes under current practice are briefly introduced and discussed. A probabilistic code format for obtaining a formal reliability evaluation system that catches the most essential features of the nature...... of the uncertainties and their interplay is the developed, step-by-step. The concepts presented are illustrated by numerous examples throughout the text....

  5. Reliability engineering theory and practice

    CERN Document Server

    Birolini, Alessandro

    2017-01-01

    This book shows how to build in and assess reliability, availability, maintainability, and safety (RAMS) of components, equipment, and systems. It presents the state of the art of reliability (RAMS) engineering, in theory & practice, and is based on over 30 years author's experience in this field, half in industry and half as Professor of Reliability Engineering at the ETH, Zurich. The book structure allows rapid access to practical results. Methods & tools are given in a way that they can be tailored to cover different RAMS requirement levels. Thanks to Appendices A6 - A8 the book is mathematically self-contained, and can be used as a textbook or as a desktop reference with a large number of tables (60), figures (210), and examples / exercises^ 10,000 per year since 2013) were the motivation for this final edition, the 13th since 1985, including German editions. Extended and carefully reviewed to improve accuracy, it represents the continuous improvement effort to satisfy reader's needs and confidenc...

  6. Design and simulation of a novel E-mode GaN MIS-HEMT based on a cascode connection for suppression of electric field under gate and improvement of reliability

    Science.gov (United States)

    Li, Weiyi; Zhang, Zhili; Fu, Kai; Yu, Guohao; Zhang, Xiaodong; Sun, Shichuang; Song, Liang; Hao, Ronghui; Fan, Yaming; Cai, Yong; Zhang, Baoshun

    2017-07-01

    We proposed a novel AlGaN/GaN enhancement-mode (E-mode) high electron mobility transistor (HEMT) with a dual-gate structure and carried out the detailed numerical simulation of device operation using Silvaco Atlas. The dual-gate device is based on a cascode connection of an E-mode and a D-mode gate. The simulation results show that electric field under the gate is decreased by more than 70% compared to that of the conventional E-mode MIS-HEMTs (from 2.83 MV/cm decreased to 0.83 MV/cm). Thus, with the discussion of ionized trap density, the proposed dual-gate structure can highly improve electric field-related reliability, such as, threshold voltage stability. In addition, compared with HEMT with field plate structure, the proposed structure exhibits a simplified fabrication process and a more effective suppression of high electric field. Project supported by the Key Technologies Support Program of Jiangsu Province (No. BE2013002-2) and the National Key Scientific Instrument and Equipment Development Projects of China (No. 2013YQ470767).

  7. Design and simulation of a novel E-mode GaN MIS-HEMT based on a cascode connection for suppression of electric field under gate and improvement of reliability

    Institute of Scientific and Technical Information of China (English)

    Weiyi Li; Yong Cai; Baoshun Zhang; Zhili Zhang; Kai Fu; Guohao Yu; Xiaodong Zhang; Shichuang Sun; Liang Song; Ronghui Hao; Yaming Fan

    2017-01-01

    We proposed a novel AlGaN/GaN enhancement-mode (E-mode) high electron mobility transistor (HEMT) with a dual-gate structure and carried out the detailed numerical simulation of device operation using Silvaco Atlas.The dual-gate device is based on a cascode connection of an E-mode and a D-mode gate.The simulation results show that electric field under the gate is decreased by more than 70% compared to that of the conventional E-mode MIS-HEMTs (from 2.83 MV/cm decreased to 0.83 MV/cm).Thus,with the discussion of ionized trap density,the proposed dual-gate structure can highly improve electric field-related reliability,such as,threshold voltage stability.In addition,compared with HEMT with field plate structure,the proposed structure exhibits a simplified fabrication process and a more effective suppression of high electric field.

  8. Creating high reliability in health care organizations.

    Science.gov (United States)

    Pronovost, Peter J; Berenholtz, Sean M; Goeschel, Christine A; Needham, Dale M; Sexton, J Bryan; Thompson, David A; Lubomski, Lisa H; Marsteller, Jill A; Makary, Martin A; Hunt, Elizabeth

    2006-08-01

    The objective of this paper was to present a comprehensive approach to help health care organizations reliably deliver effective interventions. Reliability in healthcare translates into using valid rate-based measures. Yet high reliability organizations have proven that the context in which care is delivered, called organizational culture, also has important influences on patient safety. MODEL FOR IMPROVEMENT: Our model to improve reliability, which also includes interventions to improve culture, focuses on valid rate-based measures. This model includes (1) identifying evidence-based interventions that improve the outcome, (2) selecting interventions with the most impact on outcomes and converting to behaviors, (3) developing measures to evaluate reliability, (4) measuring baseline performance, and (5) ensuring patients receive the evidence-based interventions. The comprehensive unit-based safety program (CUSP) is used to improve culture and guide organizations in learning from mistakes that are important, but cannot be measured as rates. We present how this model was used in over 100 intensive care units in Michigan to improve culture and eliminate catheter-related blood stream infections--both were accomplished. Our model differs from existing models in that it incorporates efforts to improve a vital component for system redesign--culture, it targets 3 important groups--senior leaders, team leaders, and front line staff, and facilitates change management-engage, educate, execute, and evaluate for planned interventions.

  9. Reliability, validity and responsiveness of a Norwegian version of the Chronic Sinusitis Survey

    Directory of Open Access Journals (Sweden)

    Røssberg Edna

    2006-05-01

    Full Text Available Abstract Background The Chronic Sinusitis Survey (CSS is a valid, disease-specific questionnaire for assessing health status and treatment effectiveness in chronic rhinosinusitis. In the present study, we developed a Norwegian version of the CSS and assessed its psychometric properties. Methods In the pooled data set of 65 patients from a trial of treatment for chronic sinusitis with long-standing symptoms and signs of sinusitis on computed tomography (CT, we assessed the reliability, validity and responsiveness of the CSS. Results Test-retest reliability of the two CSS scales and the total scale ranged 0.87–0.92, while internal consistency reliability ranged 0.31–0.55. CSS subscale scores were associated with other items on sinusitis symptoms, and with the Mental health and Bodily pain scale of the SF-36. There was little association of the CSS scale scores with sinus CT findings. The patients with chronic sinusitis had worse scores on all three CSS scales than a healthy reference population (n = 42 (p Conclusion The Norwegian version of the CSS had acceptable test-retest reliability, but lower internal consistency reliability than the accepted standard criteria. The results support the construct validity of the measure and the sinusitis symptoms subscale and the total scales were responsive to change. This supports the use of the questionnaire in interventions for chronic sinusitis, but points at problems with the internal consistency reliability.

  10. Active Listening Attitude Scale (ALAS: Reliability and Validity in a Nationwide Sample of Greek Educators

    Directory of Open Access Journals (Sweden)

    Ntina Kourmousi

    2017-03-01

    Full Text Available The present study examined the Active Listening Attitude Scale (ALAS validity and reliability in a sample of 3955 Greek educators. The sample was randomly split and an exploratory factor analysis (EFA was conducted in the even subsample to evaluate the scale’s construct validity. A confirmatory factor analysis (CFA was performed in the odd subsample to confirm the three-factor model identified by the EFA. The chi square test (χ2 of the model was significant (p < 0.05, due to the large sample size. The root mean square error of approximation (RMSEA, the comparative fit index (CFI and the goodness of fit index (GFI values were 0.079, 0.969 and 0.960, respectively, further supporting the fit of the three-factor model. Cronbach’s alpha coefficient was used to test internal consistency reliability and was satisfactory exceeding 0.72 for ALAS subscales. The intercorrelations of the three subscales were all positive and significant (p < 0.001, ranging from 0.20 to 0.42. Student’s t-tests and the computation of effect sizes revealed that women scored higher on Listening Skill and Conversation Opportunity, while principals and participants trained on mental health promotion scored higher on all three subscales. The analyses confirmed the three-factor model of ALAS and demonstrated its validity and reliability in measuring Greek teachers’ active listening attitudes.

  11. Reliability and validity of a Danish adaptation of the Tinnitus Handicap Inventory.

    Science.gov (United States)

    Zachariae, R; Mirz, F; Johansen, L V; Andersen, S E; Bjerring, P; Pedersen, C B

    2000-01-01

    The objective of this study was to determine the reliability and validity of a Danish translation of the Tinnitus Handicap Inventory (THI), a self-report measure of perceived tinnitus handicap. The Danish version of the THI was administered to 50 patients reporting tinnitus as their primary complaint or secondary to hearing loss. Construct validity was assessed using tinnitus symptom rating scales, the Beck Depression Inventory (BDI), the State-Trait Anxiety Inventory (STAI), the Tinnitus Coping Style Questionnaire (TCSQ), the Eysenck Personality Questionnaire (EPQ), and perceived tinnitus loudness and pitch. The Danish translation of the THI and its subscales showed good internal consistency reliabilities (c = 0.93 to alpha = 0.74) comparable to those of the original version. High to moderate correlations were observed between THI and psychological distress, tinnitus symptom ratings, neuroticism and maladaptive tinnitus coping. A confirmatory factor analysis failed to validate the three subscales of THI, and high intercorrelations found between the subscales question whether they represent three distinct factors. The results suggest that the Danish THI-Total scale may be a reliable and valid measure of general tinnitus related distress that can be used in a clinical setting to quantify the impact of tinnitus on daily living.

  12. Reliability and validity of the Lithuanian Tinnitus Handicap Inventory.

    Science.gov (United States)

    Ulozienė, Ingrida; Balnytė, Renata; Alzbutienė, Giedrė; Arechvo, Irina; Vaitkus, Antanas; Šileikaitė, Milda; Šaferis, Viktoras; Ulozas, Virgilijus

    2016-01-01

    The aim of this study was to determine the reliability and validity of the Lithuanian version of the Tinnitus Handicap Inventory (THI), a self-report measure of perceived tinnitus handicap. A cross-sectional psychometric validation study was performed in the University Hospital. A total of 248 subjects reporting chronic tinnitus as their primary complaint or secondary to hearing loss were encluded in the study and filled in the Lithuanian version of THI. For assessment of construct validity a subgroup of 55 participants completed the Lithuanian version of the Hospital Anxiety and Depression Scale as a measure of self-perceived levels of anxiety and depression. Test-retest and internal consistency reliability as well as construct validity were calculated. The Lithuanian version of the THI and its subscales showed a robust internal consistency reliability (Cronbach's alpha=0.93) comparable to the original version. Statistically significant correlations were observed between the Lithuanian translation of the THI and the measures of self-perceived levels of anxiety and depression using HADS. Confirmatory factor analysis demonstrated that the three subscales of the THI Lithuanian version corresponded to three different factors, which strongly correlated between themselves. The results suggest that the Lithuanian version of THI maintains its original validity and may serve as reliable and valid measure of general tinnitus related distress that can be used in a clinical setting to quantify the impact of tinnitus on daily living. Copyright © 2016 The Lithuanian University of Health Sciences. Production and hosting by Elsevier Urban & Partner Sp. z o.o. All rights reserved.

  13. TARGET/CRYOCHIL - THERMODYNAMIC ANALYSIS AND SUBSCALE MODELING OF SPACE-BASED ORBIT TRANSFER VEHICLE CRYOGENIC PROPELLANT RESUPPLY

    Science.gov (United States)

    Defelice, D. M.

    1994-01-01

    The resupply of the cryogenic propellants is an enabling technology for space-based transfer vehicles. As part of NASA Lewis's ongoing efforts in micro-gravity fluid management, thermodynamic analysis and subscale modeling techniques have been developed to support an on-orbit test bed for cryogenic fluid management technologies. These efforts have been incorporated into two FORTRAN programs, TARGET and CRYOCHIL. The TARGET code is used to determine the maximum temperature at which the filling of a given tank can be initiated and subsequently filled to a specified pressure and fill level without venting. The main process is the transfer of the energy stored in the thermal mass of the tank walls into the inflowing liquid. This process is modeled by examining the end state of the no-vent fill process. This state is assumed to be at thermal equilibrium between the tank and the fluid which is well mixed and saturated at the tank pressure. No specific assumptions are made as to the processes or the intermediate thermodynamic states during the filling. It is only assumed that the maximum tank pressure occurs at the final state. This assumption implies that, during the initial phases of the filling, the injected liquid must pass through the bulk vapor in such a way that it absorbs a sufficient amount of its superheat so that moderate tank pressures can be maintained. It is believed that this is an achievable design goal for liquid injection systems. TARGET can be run with any fluid for which the user has a properties data base. Currently it will only run for hydrogen, oxygen, and nitrogen since pressure-enthalpy data sets have been included for these fluids only. CRYOCHIL's primary function is to predict the optimum liquid charge to be injected for each of a series of charge-hold-vent chilldown cycles. This information can then be used with specified mass flow rates and valve response times to control a liquid injection system for tank chilldown operations. This will

  14. The rating reliability calculator

    Directory of Open Access Journals (Sweden)

    Solomon David J

    2004-04-01

    Full Text Available Abstract Background Rating scales form an important means of gathering evaluation data. Since important decisions are often based on these evaluations, determining the reliability of rating data can be critical. Most commonly used methods of estimating reliability require a complete set of ratings i.e. every subject being rated must be rated by each judge. Over fifty years ago Ebel described an algorithm for estimating the reliability of ratings based on incomplete data. While his article has been widely cited over the years, software based on the algorithm is not readily available. This paper describes an easy-to-use Web-based utility for estimating the reliability of ratings based on incomplete data using Ebel's algorithm. Methods The program is available public use on our server and the source code is freely available under GNU General Public License. The utility is written in PHP, a common open source imbedded scripting language. The rating data can be entered in a convenient format on the user's personal computer that the program will upload to the server for calculating the reliability and other statistics describing the ratings. Results When the program is run it displays the reliability, number of subject rated, harmonic mean number of judges rating each subject, the mean and standard deviation of the averaged ratings per subject. The program also displays the mean, standard deviation and number of ratings for each subject rated. Additionally the program will estimate the reliability of an average of a number of ratings for each subject via the Spearman-Brown prophecy formula. Conclusion This simple web-based program provides a convenient means of estimating the reliability of rating data without the need to conduct special studies in order to provide complete rating data. I would welcome other researchers revising and enhancing the program.

  15. On Reliability and Validity

    OpenAIRE

    MARTINS, Gilberto de Andrade

    2007-01-01

    In order to assess, evaluate or quantify financial, equity, auditing and controllership oriented data related both to private and public sectors, the practioner or the researcher has to pay close attention to the significance and accurateness criteria of the research tools he is about to employ: validity and reliability. The validity criterion refers to the instrument capacity of assessing what it intends to assess; reliability deals with the constancy of results when the same individual or o...

  16. The Leuven Adolescent Perceived Parenting Scale (LAPPS: Reliability and Validity with French-Speaking Adolescents in Belgium

    Directory of Open Access Journals (Sweden)

    Marie Delhaye

    2012-12-01

    Full Text Available The present study examined the reliability and validity of the Leuven Adolescent Perceived Parenting Scale (LAPPS, an instrument initially developed for use with Dutch-speaking adolescents in Belgium, in French-speaking adolescents living in that same country. The instrument was administered to a sample of French-speaking adolescents ('N' = 625 and a carefully matched sample of Dutch-speaking adolescents ('N' = 630. Internal consistency (Cronbach's alpha, factor structure, and mean scores for the LAPPS subscales were highly similar across linguistic region. Finally, the LAPPS subscales showed a differential pattern of associations with an alternative measure of adolescent-parent relationships (i.e., the Emotional Autonomy Scale; EAS in the French-speaking subsample. These results clearly show that the LAPPS is a reliable and valid measure of perceived parenting in French-speaking adolescents in Belgium. Suggestions for future research on the reliability and validity of the LAPPS are outlined.

  17. Reliability and Validity of the Child and Adolescent Behavior Assessment (CABA): A Brief Structured Scale.

    Science.gov (United States)

    Morin, Amanda Leigh; Miller, Stacy Jo; Smith, Johan R; Johnson, Karen E

    2017-04-01

    Use of valid, affordable, accessible, and brief measures facilitates the assessment of mental health outcomes. The Child and Adolescent Behavior Assessment Scale, a brief, structured scale, assesses problem behavior through patient and/or informant report. The purpose of this paper is to illustrate the scale's psychometric properties. In the cross-sectional study presented, a large national sample of youth (aged 5-18) admitted for psychiatric treatment (N = 32,689) was examined. The two major domains of problem behavior assessed were Internalizing and Externalizing. Reliability was good to excellent with alpha levels ranging from 0.874 to 0.917. Additional items measured Risk Behavior (α = 0.648). Subscale total scores correlated well with the Brief Psychiatric Rating Scale for Children, 9-item version (BPRS-C-9). Exploratory and confirmatory factor analyses supported the three-factor, multidimensional model of problem behavior as satisfactory for child and adolescent use, although further research is required to refine some items for clarity and improved model fit.

  18. D5.3 Reading reliability report

    DEFF Research Database (Denmark)

    Cetin, Bilge Kartal; Galiotto, Carlo; Cetin, Kamil

    2010-01-01

    This deliverable presents a detailed description of the main causes of reading reliability degradation. Two main groups of impairments are recognized: those at the physical layer (e.g., fading, multipath, electromagnetic interference, shadowing due to obstacles, tag orientation misalignment, tag...... bending, metallic environments, etc.) and those at the medium access control sub-layer (e.g., collisions due to tag-to-tag, reader-to-reader and multiple readers-to-tag interference). The review presented in this deliverable covers previous reliability reports and existing definitions of RFID reading...... reliability. Performance metrics and methodologies for assessing reading reliability are further discussed. This document also presents a review of state-of-the-art RFID reading reliability improvement schemes. The solutions are classified into physical- (PHY), medium access control- (MAC), upper-, and cross...

  19. Reliability of Power Electronic Converter Systems

    DEFF Research Database (Denmark)

    -link capacitance in power electronic converter systems; wind turbine systems; smart control strategies for improved reliability of power electronics system; lifetime modelling; power module lifetime test and state monitoring; tools for performance and reliability analysis of power electronics systems; fault......The main aims of power electronic converter systems (PECS) are to control, convert, and condition electrical power flow from one form to another through the use of solid-state electronics. This book outlines current research into the scientific modeling, experimentation, and remedial measures...... for advancing the reliability, availability, system robustness, and maintainability of PECS at different levels of complexity. Drawing on the experience of an international team of experts, this book explores the reliability of PECS covering topics including an introduction to reliability engineering in power...

  20. Reliability of Power Electronic Converter Systems

    DEFF Research Database (Denmark)

    The main aims of power electronic converter systems (PECS) are to control, convert, and condition electrical power flow from one form to another through the use of solid-state electronics. This book outlines current research into the scientific modeling, experimentation, and remedial measures...... for advancing the reliability, availability, system robustness, and maintainability of PECS at different levels of complexity. Drawing on the experience of an international team of experts, this book explores the reliability of PECS covering topics including an introduction to reliability engineering in power......-link capacitance in power electronic converter systems; wind turbine systems; smart control strategies for improved reliability of power electronics system; lifetime modelling; power module lifetime test and state monitoring; tools for performance and reliability analysis of power electronics systems; fault...

  1. Testing the validity and reliability of an instrument to measure nurses' antipathy towards patients who self-harm: Korean version of the Self-Harm Antipathy Scale.

    Science.gov (United States)

    Kwon, ChaeRyung; Lee, EunNam

    2017-07-01

    To investigate the validity and reliability of the Korean version of the Self-Harm Antipathy Scale (SHAS-K) to be used to measure nurses' antipathy towards patients who self-harm. The internal consistency reliability and construct validity, using exploratory and confirmatory factor analysis, was evaluated.The survey data were collected from 249 nurses who worked in emergency care facilities in South Korea. The Cronbach's α values regarding internal consistency were 0.54-0.88 for the subscales of the SHAS-K. The factor loadings of the 26 items on the four subscales ranged from 0.44 to 0.86. The four-subscale model was validated by a confirmatory factor analysis. This study shows that the SHAS-K should be used with caution when measuring nurses' antipathy towards patients in Korea who self-harm. © 2016 Japan Academy of Nursing Science.

  2. Differential Item Functioning in the SF-36 Physical Functioning and Mental Health Sub-Scales: A Population-Based Investigation in the Canadian Multicentre Osteoporosis Study.

    Directory of Open Access Journals (Sweden)

    Lisa M Lix

    Full Text Available Self-reported health status measures, like the Short Form 36-item Health Survey (SF-36, can provide rich information about the overall health of a population and its components, such as physical, mental, and social health. However, differential item functioning (DIF, which arises when population sub-groups with the same underlying (i.e., latent level of health have different measured item response probabilities, may compromise the comparability of these measures. The purpose of this study was to test for DIF on the SF-36 physical functioning (PF and mental health (MH sub-scale items in a Canadian population-based sample.Study data were from the prospective Canadian Multicentre Osteoporosis Study (CaMos, which collected baseline data in 1996-1997. DIF was tested using a multiple indicators multiple causes (MIMIC method. Confirmatory factor analysis defined the latent variable measurement model for the item responses and latent variable regression with demographic and health status covariates (i.e., sex, age group, body weight, self-perceived general health produced estimates of the magnitude of DIF effects.The CaMos cohort consisted of 9423 respondents; 69.4% were female and 51.7% were less than 65 years. Eight of 10 items on the PF sub-scale and four of five items on the MH sub-scale exhibited DIF. Large DIF effects were observed on PF sub-scale items about vigorous and moderate activities, lifting and carrying groceries, walking one block, and bathing or dressing. On the MH sub-scale items, all DIF effects were small or moderate in size.SF-36 PF and MH sub-scale scores were not comparable across population sub-groups defined by demographic and health status variables due to the effects of DIF, although the magnitude of this bias was not large for most items. We recommend testing and adjusting for DIF to ensure comparability of the SF-36 in population-based investigations.

  3. Reliability of provocative tests of motion sickness susceptibility

    Science.gov (United States)

    Calkins, D. S.; Reschke, M. F.; Kennedy, R. S.; Dunlop, W. P.

    1987-01-01

    Test-retest reliability values were derived from motion sickness susceptibility scores obtained from two successive exposures to each of three tests: (1) Coriolis sickness sensitivity test; (2) staircase velocity movement test; and (3) parabolic flight static chair test. The reliability of the three tests ranged from 0.70 to 0.88. Normalizing values from predictors with skewed distributions improved the reliability.

  4. Reliability analysis of the combined district heating systems

    Science.gov (United States)

    Sharapov, V. I.; Orlov, M. E.; Kunin, M. V.

    2015-12-01

    Technologies that improve the reliability and efficiency of the combined district heating systems in urban areas are considered. The calculation method of reliability of the CHP combined district heating systems is proposed. The comparative estimation of the reliability of traditional and combined district heating systems is performed.

  5. The impact of reliability on the productivity of railroad companies

    DEFF Research Database (Denmark)

    Abate, Megersa Abera; Lijesen, Mark; Pels, Eric

    2013-01-01

    This paper studies the relationship between reliability (proxied by punctuality) and productivity in passenger railroad services. Increasing reliability may lower productivity, as it requires inputs, that can’t be used to produce outputs. The relationship between reliability and productivity also...... the productivity of railway operations and aiming to improve both may be a feasible strategy. © 2013 Elsevier Ltd. All rights reserved....

  6. Study and implementation of a thermal acceleration test for the improvement of the quality and reliability of components and systems; Estudo e implementacao de um teste de aceleracao termica para a melhoria da qualidade e confiabilidade de componentes e sistemas

    Energy Technology Data Exchange (ETDEWEB)

    Leao, Felippe Carneiro

    1993-09-01

    The objective of this work is to introduce the application of the burn-in test (test of thermal acceleration) in electronic products, using the practical example of this test in a power supply and to do an analysis of the application of this test in a production line showing the advantages and disadvantages of its implementation. For that it is made an abbreviation presentation of the basic concepts of quality and reliability. Starting from these concepts are presented the statistical models used in reliability, that describe the behavior of life of products and components. Besides showing, from the speed chemical reaction model , the influence of the temperature about this reliability.

  7. Simvastatin improves the sexual health-related quality of life in men aged 40 years and over with erectile dysfunction: additional data from the erectile dysfunction and statin trial.

    Science.gov (United States)

    Trivedi, Daksha; Wellsted, David M; Collard, Jade B; Kirby, Michael

    2014-03-05

    Erectile dysfunction is prevalent in men over 40 years, affecting their quality of life and that of their partners. The aims of this study were:a) To evaluate the internal reliability of the male erectile dysfunction specific quality of life (MED-QoL) scale and explore its factor structure.b) To evaluate the effect of simvastatin on subscales of the MED-QoL in men over forty years with erectile dysfunction. This is a double blind randomised controlled trial of 40 mg simvastatin or placebo given once daily for six months to men over forty years with untreated erectile dysfunction, who were not at high cardiovascular risk and were not on anti-hypertensive or lipid-lowering medication. 173 eligible men were recruited from 10 general practices in East of England. Data were collected at two points over 30 weeks.We report on the factor structure of MED-QoL, the internal reliability of the scale and the derived subscales, and the effect of simvastatin on MED-QoL subscales. An initial analysis of the MED-QoL items suggested that a number of items should be removed (MED-QoL-R). Exploratory factor analysis identified three subscales within the MED-QoL-R which accounted for 96% of the variance, related to feelings of Control, initiating Intimacy, and Emotional response to erectile dysfunction. The alpha value for the revised scale (MED-Qol-R) was >0.95 and exceeded .82 for each subscale. Regression analysis showed that patients in the placebo group experienced a significantly reduced feeling of Control over erectile dysfunction than those in the statin group. Those in the placebo group had significantly lower Emotional response than those in the statin group at the close of trial, but there was no significant treatment effect on Intimacy. Our revised MED-QoL-R identified three subscales. Secondary analysis showed a significant improvement in sexual health related quality of life, specifically in relation to perception of control and emotional health in men with untreated

  8. Hardware and software reliability estimation using simulations

    Science.gov (United States)

    Swern, Frederic L.

    1994-01-01

    The simulation technique is used to explore the validation of both hardware and software. It was concluded that simulation is a viable means for validating both hardware and software and associating a reliability number with each. This is useful in determining the overall probability of system failure of an embedded processor unit, and improving both the code and the hardware where necessary to meet reliability requirements. The methodologies were proved using some simple programs, and simple hardware models.

  9. Offshore wind turbines reliability, availability and maintenance

    CERN Document Server

    Tavner, Peter

    2012-01-01

    The first book to specifically focus on offshore wind turbine technology and which addresses practically wind turbine reliability and availability. The book draws on the author's experience of power generation reliability and availability and the condition monitoring of that plant to describe the problems facing the developers of offshore wind farms and the solutions available to them to raise availability, reduce cost of energy and improve through life cost.

  10. Reliability in automotive and mechanical engineering determination of component and system reliability

    CERN Document Server

    Bertsche, Bernd

    2008-01-01

    In the present contemporary climate of global competition in every branch of engineering and manufacture it has been shown from extensive customer surveys that above every other attribute, reliability stands as the most desired feature in a finished product. To survive this relentless fight for survival any organisation, which neglect the plea of attaining to excellence in reliability, will do so at a serious cost Reliability in Automotive and Mechanical Engineering draws together a wide spectrum of diverse and relevant applications and analyses on reliability engineering. This is distilled into this attractive and well documented volume and practising engineers are challenged with the formidable task of simultaneously improving reliability and reducing the costs and down-time due to maintenance. The volume brings together eleven chapters to highlight the importance of the interrelated reliability and maintenance disciplines. They represent the development trends and progress resulting in making this book ess...

  11. Reliability and Validity of the Perspectives of Support From God Scale

    Science.gov (United States)

    Hamilton, Jill B.; Crandell, Jamie L.; Carter, J. Kameron; Lynn, Mary R.

    2010-01-01

    Background Existing spiritual support scales for use with cancer survivors focus on the support believed to come from a religious community, clergy, or health care providers. Objective The objective of this study was to evaluate the reliability and validity of a new measure of spiritual support believed to come from God in older Christian African American cancer survivors. Methods The Perceived Support From God Scale was administered to 317 African American cancer survivors aged 55–89 years. Psychometric evaluation involved identifying underlying factors, conducting item analysis and estimating reliability, and obtaining evidence on the relationship to other variables or the extent to which the Perceived Support From God Scale correlates with religious involvement and depression. Results The Perceived Support From God Scale consists of 15 items in two subscales (Support From God and God’s Purpose for Me). The two subscales explained 59% of the variance. Cronbach’s α coefficients were .94 and .86 for the Support From God and God’s Purpose for Me subscales, respectively. Test–retest correlations were strong, supporting the temporal stability of the instrument. Pearson’s correlations to an existing religious involvement and beliefs scale were moderate to strong. Subscale scores on Support From God were negatively correlated to depression. Discussion Initial support for reliability and validity was demonstrated for the Perceived Support From God Scale. The scale captures a facet of spirituality not emphasized in other measures. Further research is needed to evaluate the scale with persons of other racial/ethnic groups and to explore the relationship of spirituality to other outcome measures. PMID:20216012

  12. Gearbox Reliability Collaborative Update (Presentation)

    Energy Technology Data Exchange (ETDEWEB)

    Sheng, S.; Keller, J.; Glinsky, C.

    2013-10-01

    This presentation was given at the Sandia Reliability Workshop in August 2013 and provides information on current statistics, a status update, next steps, and other reliability research and development activities related to the Gearbox Reliability Collaborative.

  13. Validity and reliability of the Family Empowerment Scale for caregivers of adults with mental health issues.

    Science.gov (United States)

    Kageyama, M; Nakamura, Y; Kobayashi, S; Yokoyama, K

    2016-10-01

    WHAT IS KNOWN ON THE SUBJECT?: Empowerment of family caregivers of adults with mental health issues has received increasing attention among mental health nurses in Japan and has been recognized as a new goal of family interventions. The Family Empowerment Scale (FES) was originally developed to measure the empowerment status of parents of children with emotional disorders. However, it was later applied to broader health issues. WHAT THIS PAPER ADDS TO EXISTING KNOWLEDGE?: We developed a Japanese version of the FES for family caregivers of adults with mental health issues (FES-AMJ) and examined the validity and reliability among parents. Results showed that the FES-AMJ had acceptable concurrent validity and reliability; however, insufficient construct validity was found, especially for the subscale regarding the service system. WHAT ARE THE IMPLICATIONS FOR PRACTICE?: Further studies need to modify the scale. Clarification of ideal family empowerment status in the service system through discussion with mental health nurses and family caregivers may be important. Introduction The Family Empowerment Scale (FES) was originally developed for parents of children with emotional disorders. In Japan, family empowerment is gaining increasing attention and may be one goal of nursing interventions. Aim To develop a Japanese version of the FES for family caregivers of adults with mental health issues and to study the validity and reliability of this scale among parents. Method We translated the FES into Japanese and administered this self-report questionnaire to 275 parents. Results The multitrait scaling analysis revealed acceptable convergent validity and insufficient discriminant validity among all subscales. In particular, all items of the Service system subscale had insufficient discriminant and/or convergent validity. Each subscale significantly correlated with the indicator of empowerment. The intraclass correlation coefficients of each subscale were .855-.917. Cronbach

  14. Preliminary testing of the reliability and feasibility of SAGE: a system to measure and score engagement with and use of research in health policies and programs.

    Science.gov (United States)

    Makkar, Steve R; Williamson, Anna; D'Este, Catherine; Redman, Sally

    2017-12-19

    Few measures of research use in health policymaking are available, and the reliability of such measures has yet to be evaluated. A new measure called the Staff Assessment of Engagement with Evidence (SAGE) incorporates an interview that explores policymakers' research use within discrete policy documents and a scoring tool that quantifies the extent of policymakers' research use based on the interview transcript and analysis of the policy document itself. We aimed to conduct a preliminary investigation of the usability, sensitivity, and reliability of the scoring tool in measuring research use by policymakers. Nine experts in health policy research and two independent coders were recruited. Each expert used the scoring tool to rate a random selection of 20 interview transcripts, and each independent coder rated 60 transcripts. The distribution of scores among experts was examined, and then, interrater reliability was tested within and between the experts and independent coders. Average- and single-measure reliability coefficients were computed for each SAGE subscales. Experts' scores ranged from the limited to extensive scoring bracket for all subscales. Experts as a group also exhibited at least a fair level of interrater agreement across all subscales. Single-measure reliability was at least fair except for three subscales: Relevance Appraisal, Conceptual Use, and Instrumental Use. Average- and single-measure reliability among independent coders was good to excellent for all subscales. Finally, reliability between experts and independent coders was fair to excellent for all subscales. Among experts, the scoring tool was comprehensible, usable, and sensitive to discriminate between documents with varying degrees of research use. Secondly, the scoring tool yielded scores with good reliability among the independent coders. There was greater variability among experts, although as a group, the tool was fairly reliable. The alignment between experts' and independent

  15. Examining the Role of Predictor Variables of Mental Health and Personality Subscales in Internet Addiction of Students in Medical and non-Medical Universities of Sanandaj in 2014

    Directory of Open Access Journals (Sweden)

    Afshin Salahian

    2015-12-01

    Full Text Available Background and objective: According to the high and increasing prevalence of internet addiction, and the fact that little research has been done on the predictors of internet addiction in Iran, the purpose of this study was to examine the role of predictor variables of mental health and personality subscales in internet addiction of students in medical and non-medical universities of Sanandaj in 2014. Methods: The Method of this research was correlation and the statistical population were all of medical and non-medical students of Sanandaj Universities in 2014. In this study, 250 students (125 female and 125 male, were randomly selected, and completed the checklist of mental health symptoms, NEO personality questionnaire, and internet addiction questionnaire. Data were analyzed using Pearson Correlation, stepwise regression, and T test by SPSS software version 20. Results: The results indicated that obsession-compulsion, openness, consciousness, aggression and somatization subscales had predictor roles in internet addiction, and totally 51 percent of variances predicted the internet addiction (F=29.97; P=0.001. Conclusion: The internet addiction of university students is dependent upon their mental health and personality, and one can predict the internet addiction of students via subscales of mental health and personality.

  16. Structural Reliability Methods

    DEFF Research Database (Denmark)

    Ditlevsen, Ove Dalager; Madsen, H. O.

    The structural reliability methods quantitatively treat the uncertainty of predicting the behaviour and properties of a structure given the uncertain properties of its geometry, materials, and the actions it is supposed to withstand. This book addresses the probabilistic methods for evaluation...

  17. EXPLOITATION RELIABILITY OF RECUPERATORS

    OpenAIRE

    A. M. Selutin; V. A. Zharanov; A. V. Tkachenko

    2006-01-01

    The investigations and experience of implementation of constructions, that provide increase of gas-tightness of heat-exchangers, are described in the article. The given variants of compensators of different types allow to increase the reliability of operation of systems of the fuel furnaces waste flue gases heat using.

  18. EXPLOITATION RELIABILITY OF RECUPERATORS

    Directory of Open Access Journals (Sweden)

    A. M. Selutin

    2006-01-01

    Full Text Available The investigations and experience of implementation of constructions, that provide increase of gas-tightness of heat-exchangers, are described in the article. The given variants of compensators of different types allow to increase the reliability of operation of systems of the fuel furnaces waste flue gases heat using.

  19. Reliability based structural design

    NARCIS (Netherlands)

    Vrouwenvelder, A.C.W.M.

    2013-01-01

    According to ISO 2394, structures shall be designed, constructed and maintained in such a way that they are suited for their use during the design working life in an economic way. To fulfil this requirement one needs insight into the risk and reliability under expected and non-expected actions. A

  20. The value of reliability

    DEFF Research Database (Denmark)

    Fosgerau, Mogens; Karlström, Anders

    2010-01-01

    We derive the value of reliability in the scheduling of an activity of random duration, such as travel under congested conditions. Using a simple formulation of scheduling utility, we show that the maximal expected utility is linear in the mean and standard deviation of trip duration, regardless...

  1. Reliability and Model Fit

    Science.gov (United States)

    Stanley, Leanne M.; Edwards, Michael C.

    2016-01-01

    The purpose of this article is to highlight the distinction between the reliability of test scores and the fit of psychometric measurement models, reminding readers why it is important to consider both when evaluating whether test scores are valid for a proposed interpretation and/or use. It is often the case that an investigator judges both the…

  2. Reliability of Plastic Slabs

    DEFF Research Database (Denmark)

    Thoft-Christensen, Palle

    1989-01-01

    In the paper it is shown how upper and lower bounds for the reliability of plastic slabs can be determined. For the fundamental case it is shown that optimal bounds of a deterministic and a stochastic analysis are obtained on the basis of the same failure mechanisms and the same stress fields....

  3. Travel time reliability modeling.

    Science.gov (United States)

    2011-07-01

    This report includes three papers as follows: : 1. Guo F., Rakha H., and Park S. (2010), "A Multi-state Travel Time Reliability Model," : Transportation Research Record: Journal of the Transportation Research Board, n 2188, : pp. 46-54. : 2. Park S.,...

  4. Parametric Mass Reliability Study

    Science.gov (United States)

    Holt, James P.

    2014-01-01

    The International Space Station (ISS) systems are designed based upon having redundant systems with replaceable orbital replacement units (ORUs). These ORUs are designed to be swapped out fairly quickly, but some are very large, and some are made up of many components. When an ORU fails, it is replaced on orbit with a spare; the failed unit is sometimes returned to Earth to be serviced and re-launched. Such a system is not feasible for a 500+ day long-duration mission beyond low Earth orbit. The components that make up these ORUs have mixed reliabilities. Components that make up the most mass-such as computer housings, pump casings, and the silicon board of PCBs-typically are the most reliable. Meanwhile components that tend to fail the earliest-such as seals or gaskets-typically have a small mass. To better understand the problem, my project is to create a parametric model that relates both the mass of ORUs to reliability, as well as the mass of ORU subcomponents to reliability.

  5. Reliability of semiology description.

    Science.gov (United States)

    Heo, Jae-Hyeok; Kim, Dong Wook; Lee, Seo-Young; Cho, Jinwhan; Lee, Sang-Kun; Nam, Hyunwoo

    2008-01-01

    Seizure semiology is important for classifying patients' epilepsy. Physicians usually get most of the seizure information from observers though there have been few reports on the reliability of the observers' description. This study aims at determining the reliability of observers' description of the semiology. We included 92 patients who had their habitual seizures recorded during video-EEG monitoring. We compared the semiology described by the observers with that recorded on the videotape, and reviewed which characteristics of the observers affected the reliability of their reported data. The classification of seizures and the individual components of the semiology based only on the observer-description was somewhat discordant compared with the findings from the videotape (correct classification, 85%). The descriptions of some ictal behaviors such as oroalimentary automatism, tonic/dystonic limb posturing, and head versions were relatively accurate, but those of motionless staring and hand automatism were less accurate. The specified directions by the observers were relatively correct. The accuracy of the description was related to the educational level of the observers. Much of the information described by well-educated observers is reliable. However, every physician should keep in mind the limitations of this information and use this information cautiously.

  6. Reliability measurement without limits

    NARCIS (Netherlands)

    Reidsma, Dennis; Carletta, J.

    In computational linguistics, a reliability measurement of 0.8 on some statistic such as $\\kappa$ is widely thought to guarantee that hand-coded data is fit for purpose, with lower values suspect. We demonstrate that the main use of such data, machine learning, can tolerate data with a low

  7. High reliability organizations

    NARCIS (Netherlands)

    Gallis, R.; Zwetsloot, G.I.J.M.

    2014-01-01

    High Reliability Organizations (HRO’s) are organizations that constantly face serious and complex (safety) risks yet succeed in realising an excellent safety performance. In such situations acceptable levels of safety cannot be achieved by traditional safety management only. HRO’s manage safety

  8. Reliability and validity of the SF-36 Health Survey Questionnaire in patients with brain tumors: a cross-sectional study.

    Science.gov (United States)

    Bunevicius, Adomas

    2017-05-04

    Deterioration of health related quality of life (HRQoL) is common in brain tumor patients. This study evaluated validity and reliability of the Medical Outcomes Study 36-Item Short Form (SF-36) in patients with brain tumors. Two hundred and seventy-seven patients admitted for brain tumor surgery were evaluated for HRQoL (SF-36 questionnaire); depressive symptoms (Beck Depression Inventory-II or BDI-II); and functional status (Barthel index or BI). Final histological diagnosis was obtained from pathology reports. Two-hundred and twenty-seven (completion rate of 82%) patients (69% women; mean age 55.8 ± 14.4 years) completed the SF-36 questionnaire. The most common brain tumor diagnosis was meningioma (40%), followed high-grade glioma (19%). Missing data rates were ≤4%. Internal consistency was adequate for all (Cronbach α ≥ .728) but Social Functioning (Cronbach α = .527) and General Health (Cronbach α = .693) subscales. Ceiling (≥36%) and floor (≥22%) effect rates were the greatest for the Role Limitations subscales. The SF-36 subscales pertaining physical health correlated the strongest with the BI score, while the SF-36 subscales pertaining emotional health correlated the strongest with the BDI-II score. Patients with mild-moderate depressive symptoms (BDI-II score ≥20) scored lower across all SF-36 subscales, and handicap patients (BI score SF-36 is a valid and reliable instrument in brain tumor patients and therefore can be reliably applied for evaluation of HRQoL in neuro-oncology setting. Further studies exploring other psychometric properties of the SF-36 in brain tumor patients across disease progression stages are warranted.

  9. Development and reliability of a Telephone-Administered Perceived Racism Scale (TPRS): a tool for epidemiological use.

    Science.gov (United States)

    Vines, A I; McNeilly, M D; Stevens, J; Hertz-Picciotto, I; Baird, M; Baird, D D

    2001-01-01

    The conceptualization of perceived racism as a chronic stressor is relatively new to epidemiology. The Telephone-Administered Perceived Racism Scale (TPRS) captures the complexity of racism within five scales: Experience of Racism (by Blacks as a group and by the respondent), Emotional Responses, Behavioral Responses, Concern for Child(ren), and Past Experiences of Racism. The TPRS was developed for employed Black women. Exploratory factor analyses and tests of internal consistency were completed with 476 Black women, aged 36-53. Factor analyses on their responses to racism yielded five factors: passive emotions, active emotions, passive behaviors, internal active behaviors, and external active behaviors. Alpha reliability values ranged from 0.75 to 0.80 for the active and passive emotions subscales, from 0.59 to 0.69 for the passive behaviors subscale, and greater than 0.76 for both active behaviors subscales. Alpha reliabilities were 0.82, 0.90, 0.88, and 0.82 for Past Experiences, Concern for Child(ren), Experience of Racism--Personal, and Experience of Racism--Group, respectively. Another 30 Black women were queried for test-retest reliability, with values ranging from 0.61 to 0.82. The TPRS was found to be reliable and should serve as a useful epidemiological tool in the examination of the effects of perceived racism on Black women's health.

  10. [Validity, reliability, and acceptability of the brief version of the self-management knowledge, attitude, and behavior assessment scale for diabetes patients].

    Science.gov (United States)

    Wu, Y Z; Wang, W J; Feng, N P; Chen, B; Li, G C; Liu, J W; Liu, H L; Yang, Y Y

    2016-07-06

    To evaluate the validity, reliability, and acceptability of the brief version of the self-management knowledge, attitude, and behavior (KAB) assessment scale for diabetes patients. Diabetes patients who were managed at the Xinkaipu Community Health Service Center of Tianxin in Changsha, Hunan Province were selected for survey by cluster sampling. A total of 350 diabetes patients were surveyed using the brief scale to collect data on knowledge, attitudes, and behaviors of self-management. Content validity was evaluated by Pearson correlation coefficient between the brief scale and subscales of knowledge, attitude, and behavior. Structure validity was evaluated by factor analysis, and discrimination validity was evaluated by an independent sample t-test between the high-score and low-score groups. Reliability was tested by internal consistency reliability and split-half reliability. The evaluation indexes of internal consistency reliability were Cronbach's α coefficients, θ coefficient, and Ω coefficient. Acceptability was evaluated by valid response rate and completion time of the brief scale. A total of 346(98.9%) valid questionnaires were returned, with average survey time of (11.43±3.4) minutes. Average score of the brief scale was 78.85 ± 11.22; scores of the knowledge, attitude, and behavior subscales were 16.45 ± 4.42, 21.33 ± 2.03, and 41.07 ± 8.34, respectively. Pearson correlation coefficients between the brief scale and the knowledge, attitude, and behavior subscales were 0.92, 0.42, and 0.60, respectively; P-values were all less than 0.01, indicating that the face validity and content validity of the brief scale were achieved to a good level. The common factor cumulative variance contribution rate of the brief scale and three subscales was from 53.66% to 61.75%, which achieved more than 50% of the approved standard. There were 11 common factors; 41 of the total 42 items had factor loadings above 0.40 in their relevant common factor, indicating

  11. 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....

  12. Reliability of short form-36 in an Internet- and a pen-and-paper version

    DEFF Research Database (Denmark)

    Basnov, Maja; Kongsved, Sissel Marie; Bech, Per

    2009-01-01

    Use of Internet versions of questionnaires may have several advantages in clinical and epidemiological research, but we know little about if Internet versions differ with respect to validity and reliability. We aimed to compare Internet- and pen-and-paper versions of short form-36 (SF-36......) with respect to test-retest reliability and internal consistency. Women referred to mammography (n = 782) were randomised to receive either a paper version with a prepaid return envelope or a guideline on how to fill in the Internet version. A subgroup was asked to answer the questionnaire once again...... in the alternative version. Test-retest reliability was assessed by the intra-class correlation coefficient. Internal consistency was calculated as Cronbach's alpha. The between-version test-retest reliability for the eight subscales were between 0.63 and 0.92. Cronbach's alpha for the two versions were all between...

  13. Self-esteem among nursing assistants: reliability and validity of the Rosenberg Self-Esteem Scale.

    Science.gov (United States)

    McMullen, Tara; Resnick, Barbara

    2013-01-01

    To establish the reliability and validity of the Rosenberg Self-Esteem Scale (RSES) when used with nursing assistants (NAs). Testing the RSES used baseline data from a randomized controlled trial testing the Res-Care Intervention. Female NAs were recruited from nursing homes (n = 508). Validity testing for the positive and negative subscales of the RSES was based on confirmatory factor analysis (CFA) using structural equation modeling and Rasch analysis. Estimates of reliability were based on Rasch analysis and the person separation index. Evidence supports the reliability and validity of the RSES in NAs although we recommend minor revisions to the measure for subsequent use. Establishing reliable and valid measures of self-esteem in NAs will facilitate testing of interventions to strengthen workplace self-esteem, job satisfaction, and retention.

  14. [The Basel Interview for Psychosis (BIP): structure, reliability and validity].

    Science.gov (United States)

    Riecher-Rössler, A; Ackermann, T; Uttinger, M; Ittig, S; Koranyi, S; Rapp, C; Bugra, H; Studerus, E

    2015-02-01

    Although several instruments have been developed to identify patients with an at-risk mental state (ARMS) for psychosis and first episode of psychosis (FEP), up to now there were no instruments for a detailed assessment of risk factors and indicators of emerging psychosis and the temporal development of psychiatric symptoms over the whole life span in these patients. We therefore developed the Basle Interview for Psychosis (BIP). The aim of this study is to describe the development of the BIP and to report about its psychometric properties. The BIP is a comprehensive semi-structured interview that was developed for the Basel early detection of psychoses (FePsy) study. Its items were derived from the most important risk factors and indicators of psychosis described in the literature and from several existing instruments. It contains the following six sections: 1) social and physical development and family, 2) signs and symptoms, 3) vulnerability, 4) help-seeking behavior, 5) illness insight, 6) evaluation of the interview. To estimate the inter-rater reliabilities of the items of sections 2 and 3, 20 interviews were conducted and rated by 8 well-trained raters. The factorial structure of the BIP section "signs and symptoms" was explored in a sample of 120 ARMS and 77 FEP patients. On the basis of the discovered factorial structure, we created new subscales and assessed their reliabilities and validities. Of the 153 studied items of sections 2 and 3, 150 (98 %) were rated with sufficiently high agreement (inter-rater reliability > 0.4). The items of section "signs and symptoms" could be grouped into 5 subscales with predominantly good to very good internal consistencies, homogeneities, and discriminant and convergent validities. Predictive validities could be demonstrated for the subscales "Positive Psychotic Symptoms", "Disturbance of Thinking" and the total score. The BIP is the first interview for comprehensively assessing risk factors and indicators of

  15. Measuring the Safety of Excreta Disposal Behavior in India with the New Safe San Index: Reliability, Validity and Utility

    Directory of Open Access Journals (Sweden)

    Marion W. Jenkins

    2014-08-01

    Full Text Available Methods to assess household excreta disposal practices are critical for informing public health outcomes of efforts to improve sanitation in developing countries. We present a new metric, the Safe San Index (SSI, to quantify the hygienic safety of a household’s defecation and human feces disposal practices in India, where behavioral outcomes from on-going public expenditures to construct household sanitation facilities and eliminate open defecation are poorly measured. We define hygienic safety of feces disposal as capture in a hygienic sanitation facility. The SSI consists of 15 self-report items and two sub-scales, Latrine Use Frequency and Seven-Day Open Defecation Rate. Households are scored on a standardized scale from 0 (no defecation safely captured to 100 (all defecation safely captured. We present results of a pilot study in Odisha, India to apply the Index to assess excreta disposal behaviors among rural households and evaluate the reliability and validity of the Index for estimating the rate of correct and consistent sanitation facility usage of household with an improved latrine.

  16. Reliability and Validity of the Spanish Version of the Memorial Symptom Assessment Scale in Oncology Patients.

    Science.gov (United States)

    Llamas Ramos, Inés; Llamas Ramos, Rocío; Martín Nogueras, Ana María; Alvarado Omenat, Jorge Juan; Calvo Arenillas, José Ignacio; Fonseca Sánchez, Emilio; Cortés Rodríguez, María

    2016-12-01

    Memorial Symptom Assessment Scale (MSAS) is a multidimensional tool developed to evaluate frequency, severity, and distress of common symptoms present in cancer patients. To translate the original English version of MSAS and prove the reliability and validity of the Spanish version. MSAS scale was translated into Spanish and administered to 246 cancer patients aged between 18 and 85 years. They attended the Day Hospital to receive chemotherapy. European Organization for Research and Treatment of Cancer Quality of Life Questionnaire-Core 30 and Rotterdam Symptom Checklist were used to test criterion validity. TOTAL MSAS, Physical Symptom Subscale (PHYS), Psychological Symptom Subscale (PSYCH), and Global Distress Index (GDI) reported high internal consistency: 0.891, 0.801, 0.825, 0.813, respectively. Exploratory factor analysis identified two-factors structure and confirmatory factor analysis showed good adjustment rates. The emotional functioning subscale of European Organization for Research and Treatment of Cancer Quality of Life Questionnaire-Core 30 highly correlated with PSYCH (r = -0.868; P PSYCH (r = -0.704; P PSYCH with PSYCH (r = 0.872; P < 0.001). The Spanish version of MSAS was determined to be a valid and reliable scale in cancer patients. Copyright © 2016 American Academy of Hospice and Palliative Medicine. Published by Elsevier Inc. All rights reserved.

  17. Study on segmented distribution for reliability evaluation

    Directory of Open Access Journals (Sweden)

    Huaiyuan Li

    2017-02-01

    Full Text Available In practice, the failure rate of most equipment exhibits different tendencies at different stages and even its failure rate curve behaves a multimodal trace during its life cycle. As a result, traditionally evaluating the reliability of equipment with a single model may lead to severer errors. However, if lifetime is divided into several different intervals according to the characteristics of its failure rate, piecewise fitting can more accurately approximate the failure rate of equipment. Therefore, in this paper, failure rate is regarded as a piecewise function, and two kinds of segmented distribution are put forward to evaluate reliability. In order to estimate parameters in the segmented reliability function, Bayesian estimation and maximum likelihood estimation (MLE of the segmented distribution are discussed in this paper. Since traditional information criterion is not suitable for the segmented distribution, an improved information criterion is proposed to test and evaluate the segmented reliability model in this paper. After a great deal of testing and verification, the segmented reliability model and its estimation methods presented in this paper are proven more efficient and accurate than the traditional non-segmented single model, especially when the change of the failure rate is time-phased or multimodal. The significant performance of the segmented reliability model in evaluating reliability of proximity sensors of leading-edge flap in civil aircraft indicates that the segmented distribution and its estimation method in this paper could be useful and accurate.

  18. Chronic pain acceptance questionnaire: confirmatory factor analysis, reliability, and validity in Italian subjects with chronic low back pain.

    Science.gov (United States)

    Monticone, Marco; Ferrante, Simona; Rocca, Barbara; Nava, Tiziana; Parini, Chiara; Cerri, Cesare

    2013-06-01

    Cross-sectional evaluation of the psychometric properties of a translated questionnaire. To validate the Italian version of the Chronic Pain Acceptance Questionnaire (CPAQ) to allow its use with Italian-speaking patients with chronic low back pain (LBP). Growing attention is being given to cognitive-behavioral measures to improve interventions for LBP. The CPAQ has never been validated in Italian subjects with chronic LBP. The psychometric testing included confirmatory factor analysis, reliability by internal consistency (Cronbach α), test-retest reliability (intraclass correlation coefficient), sensitivity to change by calculating the smallest detectable change, and construct validity by comparing CPAQ with a pain numerical rating scale, the Roland-Morris Disability Questionnaire Scale, the Hospital Anxiety and Depression Scale, the Pain Catastrophizing Scale, and the Tampa Scale of Kinesiophobia (Pearson correlations). Hierarchical multiple regression analyses were computed to further investigate construct validity of the CPAQ subscales. The questionnaire was administered to 142 subjects with chronic LBP. Factor analysis confirmed a 2-factor (viz., Activities Engagement and Pain Willingness) 20-item solution, achieving a good data-model fit. Internal consistency (α = 0.88) and test-retest reliability (intraclass correlation coefficient = 0.86) were good. The smallest detectable change was 22. Construct validity showed a moderate correlation between the CPAQ and numerical rating scale (r = -0.485), Roland-Morris Disability Questionnaire Scale (r = -0.594), and Tampa Scale of Kinesiophobia (r = -0.595), and a close correlation with Hospital Anxiety and Depression Scale (r = -0.610 for the Anxiety score and r = -0.659 for the Depression score) and Pain Catastrophizing Scale (r = -0.658). The standardized regression coefficients for Activity Engagement were significant in all of the equations, and those for Pain Willingness were significant in the anxiety

  19. The development, validity, and reliability of the Addiction Profile Index (API).

    Science.gov (United States)

    Ögel, Kültegin; Evren, Cüneyt; Karadağ, Figen; Gürol, Defne Tamar

    2012-01-01

    The objective of this study was to develop a practical questionnaire for multidimensional assessment of problems associated with alcohol and substance abuse that would also be useful for treatment planning. The Addiction Profile Index (API) is a self-report questionnaire consisting of 37 items and the following 5 subscales: characteristics of substance use; dependency diagnosis; the effects of subsance use on the user; craving; motivation to quit using substances. The study included 345 alcohol and/or substance abusers from 2 addiction treatment clinics and a prison addiction service. The validity of the questionnaire was assessed using the Michigan Alcoholism Screening Test (MAST), Readiness to Change Questionnaire (SOCRATES), Penn Alcohol Craving Scale (PACS), Drug Craving Scale (DCS), Structured Clinical Interview for DSM-IV Axis I Disorders (SCID-I), and Addiction Severity Index (ASI). The Cronbach's alpha coefficient for the total API was 0.89 and for the subscales it ranged from 0.63 to 0.86. Item-total correlation coefficients ranged from 0.42 to 0.89. The Spearman Brown split-half method coefficient for the total API was 0.83. In all, 4 factors were obtained using explanatory factor analysis that represented 52.3% of the total variance. The API craving subscale was observed to be consistent with PACS and the API motivation subscale was consistent with SOCRATES. The API total score was strongly correlated with the mean MAST score, and the composite ASI medical status, substance use, legal status, and family social relations subscale scores. Based on ROC analyses, the area under curve was 0.90. With a total API cut-off score of 4, the scale's sensitivity and specificity 0.85 was 0.78, respectively. The findings show that the API is a valid and reliable questionnaire that can be used to measure the severity of different dimensions of substance dependency.

  20. Solder joint technology materials, properties, and reliability

    CERN Document Server

    Tu, King-Ning

    2007-01-01

    Solder joints are ubiquitous in electronic consumer products. The European Union has a directive to ban the use of Pb-based solders in these products on July 1st, 2006. There is an urgent need for an increase in the research and development of Pb-free solders in electronic manufacturing. For example, spontaneous Sn whisker growth and electromigration induced failure in solder joints are serious issues. These reliability issues are quite complicated due to the combined effect of electrical, mechanical, chemical, and thermal forces on solder joints. To improve solder joint reliability, the science of solder joint behavior under various driving forces must be understood. In this book, the advanced materials reliability issues related to copper-tin reaction and electromigration in solder joints are emphasized and methods to prevent these reliability problems are discussed.

  1. Cross-cultural adaptation and reliability and validity of the Dutch Patient-Rated Tennis Elbow Evaluation (PRTEE-D).

    Science.gov (United States)

    van Ark, Mathijs; Zwerver, Johannes; Diercks, Ronald L; van den Akker-Scheek, Inge

    2014-08-11

    Lateral Epicondylalgia (LE) is a common injury for which no reliable and valid measure exists to determine severity in the Dutch language. The Patient-Rated Tennis Elbow Evaluation (PRTEE) is the first questionnaire specifically designed for LE but in English. The aim of this study was to translate into Dutch and cross-culturally adapt the PRTEE and determine reliability and validity of the PRTEE-D (Dutch version). The PRTEE was cross-culturally adapted according to international guidelines. Participants (n = 122) were asked to fill out the PRTEE-D twice with a one week interval to assess test-retest reliability. Internal consistency of the PRTEE-D was determined by calculating Crohnbach's alphas for the questionnaire and subscales. Intraclass Correlation Coefficients (ICC) were calculated for the overall PRTEE-D score, pain and function subscale and individual questions to determine test-retest reliability. Additionally, the Disabilities for the Arm, Shoulder and Hand questionnaire (DASH) and Visual Analogue Scale (VAS) pain scores were obtained from 30 patients to assess construct validity; Spearman's correlation coefficients were calculated between the PRTEE-D (subscales) and DASH and VAS-pain scores. The PRTEE was successfully cross-culturally adapted into Dutch (PRTEE-D). Crohnbach's alpha for the first assessment of the PRTEE-D was 0.98; Crohnbach's alpha was 0.93 for the pain subscale and 0.97 for the function subscale. ICC for the PRTEE-D was 0.98; subscales also showed excellent ICC values (pain scale 0.97 and function scale 0.97). A significant moderate correlation exists between PRTEE-D and DASH (0.65) and PRTEE-D and VAS pain (0.68). The PRTEE was successfully cross-culturally adapted and this study showed that the PRTEE-D is reliable and valid to obtain an indication of severity of LE. An easy-to-use instrument for practitioners is now available and this facilitates comparing Dutch and international research data.

  2. Validity and Reliability Study of the Korean Tinetti Mobility Test for Parkinson’s Disease

    Directory of Open Access Journals (Sweden)

    Jinse Park

    2018-01-01

    Full Text Available Objective Postural instability and gait disturbance are the cardinal symptoms associated with falling among patients with Parkinson’s disease (PD. The Tinetti mobility test (TMT is a well-established measurement tool used to predict falls among elderly people. However, the TMT has not been established or widely used among PD patients in Korea. The purpose of this study was to evaluate the reliability and validity of the Korean version of the TMT for PD patients. Methods Twenty-four patients diagnosed with PD were enrolled in this study. For the interrater reliability test, thirteen clinicians scored the TMT after watching a video clip. We also used the test-retest method to determine intrarater reliability. For concurrent validation, the unified Parkinson’s disease rating scale, Hoehn and Yahr staging, Berg Balance Scale, Timed-Up and Go test, 10-m walk test, and gait analysis by three-dimensional motion capture were also used. We analyzed receiver operating characteristic curve to predict falling. Results The interrater reliability and intrarater reliability of the Korean Tinetti balance scale were 0.97 and 0.98, respectively. The interrater reliability and intra-rater reliability of the Korean Tinetti gait scale were 0.94 and 0.96, respectively. The Korean TMT scores were significantly correlated with the other clinical scales and three-dimensional motion capture. The cutoff values for predicting falling were 14 points (balance subscale and 10 points (gait subscale. Conclusion We found that the Korean version of the TMT showed excellent validity and reliability for gait and balance and had high sensitivity and specificity for predicting falls among patients with PD.

  3. Validity and Reliability Study of the Korean Tinetti Mobility Test for Parkinson's Disease.

    Science.gov (United States)

    Park, Jinse; Koh, Seong-Beom; Kim, Hee Jin; Oh, Eungseok; Kim, Joong-Seok; Yun, Ji Young; Kwon, Do-Young; Kim, Younsoo; Kim, Ji Seon; Kwon, Kyum-Yil; Park, Jeong-Ho; Youn, Jinyoung; Jang, Wooyoung

    2018-01-01

    Postural instability and gait disturbance are the cardinal symptoms associated with falling among patients with Parkinson's disease (PD). The Tinetti mobility test (TMT) is a well-established measurement tool used to predict falls among elderly people. However, the TMT has not been established or widely used among PD patients in Korea. The purpose of this study was to evaluate the reliability and validity of the Korean version of the TMT for PD patients. Twenty-four patients diagnosed with PD were enrolled in this study. For the interrater reliability test, thirteen clinicians scored the TMT after watching a video clip. We also used the test-retest method to determine intrarater reliability. For concurrent validation, the unified Parkinson's disease rating scale, Hoehn and Yahr staging, Berg Balance Scale, Timed-Up and Go test, 10-m walk test, and gait analysis by three-dimensional motion capture were also used. We analyzed receiver operating characteristic curve to predict falling. The interrater reliability and intrarater reliability of the Korean Tinetti balance scale were 0.97 and 0.98, respectively. The interrater reliability and intra-rater reliability of the Korean Tinetti gait scale were 0.94 and 0.96, respectively. The Korean TMT scores were significantly correlated with the other clinical scales and three-dimensional motion capture. The cutoff values for predicting falling were 14 points (balance subscale) and 10 points (gait subscale). We found that the Korean version of the TMT showed excellent validity and reliability for gait and balance and had high sensitivity and specificity for predicting falls among patients with PD.

  4. Accelerator reliability workshop

    Energy Technology Data Exchange (ETDEWEB)

    Hardy, L.; Duru, Ph.; Koch, J.M.; Revol, J.L.; Van Vaerenbergh, P.; Volpe, A.M.; Clugnet, K.; Dely, A.; Goodhew, D

    2002-07-01

    About 80 experts attended this workshop, which brought together all accelerator communities: accelerator driven systems, X-ray sources, medical and industrial accelerators, spallation sources projects (American and European), nuclear physics, etc. With newly proposed accelerator applications such as nuclear waste transmutation, replacement of nuclear power plants and others. Reliability has now become a number one priority for accelerator designers. Every part of an accelerator facility from cryogenic systems to data storage via RF systems are concerned by reliability. This aspect is now taken into account in the design/budget phase, especially for projects whose goal is to reach no more than 10 interruptions per year. This document gathers the slides but not the proceedings of the workshop.

  5. Human Reliability Program Workshop

    Energy Technology Data Exchange (ETDEWEB)

    Landers, John; Rogers, Erin; Gerke, Gretchen

    2014-05-18

    A Human Reliability Program (HRP) is designed to protect national security as well as worker and public safety by continuously evaluating the reliability of those who have access to sensitive materials, facilities, and programs. Some elements of a site HRP include systematic (1) supervisory reviews, (2) medical and psychological assessments, (3) management evaluations, (4) personnel security reviews, and (4) training of HRP staff and critical positions. Over the years of implementing an HRP, the Department of Energy (DOE) has faced various challenges and overcome obstacles. During this 4-day activity, participants will examine programs that mitigate threats to nuclear security and the insider threat to include HRP, Nuclear Security Culture (NSC) Enhancement, and Employee Assistance Programs. The focus will be to develop an understanding of the need for a systematic HRP and to discuss challenges and best practices associated with mitigating the insider threat.

  6. Laser System Reliability

    Science.gov (United States)

    1977-03-01

    RELIABILITY INTERACTION WITH MANAGEMENT This section describes how reliability, in a general sense, plays Into the overall development of an optimally...8217— "l ’ ^’^Tt^jli^^ D. DEFINITIONS The hierarchy of levels of the physical system breakdown plays an . important role in the total under s t andi...plp2p3p4p5I6 (J). + plp2p3p«ii5W6 * plp2p3W6 * plp2£3V5W6 * hVlVA * ilW2W3V5W6 ; (J) whore , «gain, the (J) symbol Implies that the

  7. Reliability and construction control

    Directory of Open Access Journals (Sweden)

    Sherif S. AbdelSalam

    2016-06-01

    Full Text Available The goal of this study was to determine the most reliable and efficient combination of design and construction methods required for vibro piles. For a wide range of static and dynamic formulas, the reliability-based resistance factors were calculated using EGYPT database, which houses load test results for 318 piles. The analysis was extended to introduce a construction control factor that determines the variation between the pile nominal capacities calculated using static versus dynamic formulae. From the major outcomes, the lowest coefficient of variation is associated with Davisson’s criterion, and the resistance factors calculated for the AASHTO method are relatively high compared with other methods. Additionally, the CPT-Nottingham and Schmertmann method provided the most economic design. Recommendations related to a pile construction control factor were also presented, and it was found that utilizing the factor can significantly reduce variations between calculated and actual capacities.

  8. Reliability of Circumplex Axes

    Directory of Open Access Journals (Sweden)

    Micha Strack

    2013-06-01

    Full Text Available We present a confirmatory factor analysis (CFA procedure for computing the reliability of circumplex axes. The tau-equivalent CFA variance decomposition model estimates five variance components: general factor, axes, scale-specificity, block-specificity, and item-specificity. Only the axes variance component is used for reliability estimation. We apply the model to six circumplex types and 13 instruments assessing interpersonal and motivational constructs—Interpersonal Adjective List (IAL, Interpersonal Adjective Scales (revised; IAS-R, Inventory of Interpersonal Problems (IIP, Impact Messages Inventory (IMI, Circumplex Scales of Interpersonal Values (CSIV, Support Action Scale Circumplex (SAS-C, Interaction Problems With Animals (IPI-A, Team Role Circle (TRC, Competing Values Leadership Instrument (CV-LI, Love Styles, Organizational Culture Assessment Instrument (OCAI, Customer Orientation Circle (COC, and System for Multi-Level Observation of Groups (behavioral adjectives; SYMLOG—in 17 German-speaking samples (29 subsamples, grouped by self-report, other report, and metaperception assessments. The general factor accounted for a proportion ranging from 1% to 48% of the item variance, the axes component for 2% to 30%; and scale specificity for 1% to 28%, respectively. Reliability estimates varied considerably from .13 to .92. An application of the Nunnally and Bernstein formula proposed by Markey, Markey, and Tinsley overestimated axes reliabilities in cases of large-scale specificities but otherwise works effectively. Contemporary circumplex evaluations such as Tracey’s RANDALL are sensitive to the ratio of the axes and scale-specificity components. In contrast, the proposed model isolates both components.

  9. Wind turbine reliability analysis

    OpenAIRE

    Pinar Pérez, Jesús María; García Márquez, Fausto Pedro; Tobias, Andrew Mark; Papaelias, Mayorkinos

    2013-01-01

    Against the background of steadily increasing wind power generation worldwide, wind turbine manufacturers are continuing to develop a range of configurations with different combinations of pitch control, rotor speeds, gearboxes, generators and converters. This paper categorizes the main designs, focusing on their reliability by bringing together and comparing data from a selection of major studies in the literature. These are not particularly consistent but plotting failure rates against hour...

  10. Revisiting the reliability and validity of the Entrepreneurial Attitude Orientation Scale in China.

    Science.gov (United States)

    Miao, Qing

    2012-10-01

    The Entrepreneurial Attitude Orientation (EAO) scale is a multidimensional self-report measure of attitudes toward entrepreneurship. Few studies have tested the validity and reliability of the EAO scale in different social and cultural situations. The present study examined the generalizability of the EAO scale in a Chinese context using a two-wave survey. Exploratory factor analysis with the first wave data revealed a four-factor solution consistent with the original scale with 5 items removed. Confirmatory factor analysis of the secondary wave data verified the hypothesized model with a group of parameters and an overall satisfactory fit. The analysis indicated that the Cronbach's a of the four subscales were similar to the values reported by the developers of the scale. However, the results of the test-retest r of the four subscales were lower than the original reports. The findings generally support the generalizability of the four-dimensional model of the EAO. Further research questions are discussed.

  11. Controle da qualidade no laboratório clínico: alinhando melhoria de processos, confiabilidade e segurança do paciente Quality control in clinical laboratory: aligning process improvement, reliability and patient safety

    Directory of Open Access Journals (Sweden)

    Fernando de Almeida Berlitz

    2010-10-01

    has been widely pursued as a theoretical basis for this issue is high reliability organization (HRO. In this paper we propose a new approach to analytical quality control (AQC, based on HRO principles and focused on patient safety improvement. OBJECTIVES: To propose a new approach to AQC system, aligned with HRO theory and focused on patient safety improvement. MATERIALS AND METHODS: In order to optimize the traditional AQC approach and make feasible the long term assessment of system stability, we propose a model based on evaluation of random and systematic error by means of advanced control charts. We used real data obtained from the routine to validate the simulated model (glucose, Vitros FS 5.1, OCD. RESULTS: The studied assay was evaluated in terms of long term performance and showed an adequate performance (4.1 sigma for its diagnostic use. DISCUSSION: The proposed model suggests an alternative tool based on expertise already widely applied in statistical process control in order to control long-term stability of laboratory methods. CONCLUSION: The new proposed approach, which is a complement to the traditional quality control system and involves the sequential and associated use of different statistical tools, proved to be a valid and useful model for effective performance evaluation and its ongoing performance stability.

  12. 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.

  13. Gate-Level Circuit Reliability Analysis: A Survey

    Directory of Open Access Journals (Sweden)

    Ran Xiao

    2014-01-01

    Full Text Available Circuit reliability has become a growing concern in today’s nanoelectronics, which motivates strong research interest over the years in reliability analysis and reliability-oriented circuit design. While quite a few approaches for circuit reliability analysis have been reported, there is a lack of comparative studies on their pros and cons in terms of both accuracy and efficiency. This paper provides an overview of some typical methods for reliability analysis with focus on gate-level circuits, large or small, with or without reconvergent fanouts. It is intended to help the readers gain an insight into the reliability issues, and their complexity as well as optional solutions. Understanding the reliability analysis is also a first step towards advanced circuit designs for improved reliability in the future research.

  14. Factor structure, reliability, and validity of the Chinese version of the School Bullying Experience Questionnaire

    Directory of Open Access Journals (Sweden)

    Cheng-Fang Yen

    2012-09-01

    Full Text Available The aims of this study were to examine the factor structure, internal consistency, 1-month test–retest reliability, and congruent validity of the Chinese version of the School Bullying Experience Questionnaire (C-SBEQ. Study 1, in which 5751 Taiwanese adolescents in Southern Taiwan participated, examined the adequacy of the original four-factor structure of the C-SBEQ using confirmatory factor analysis (CFA and internal-consistency reliability using Cronbach α. Study 2, in which 108 adolescents in Southern Taiwan participated, examined the 1-month test–retest reliability using intraclass correlation coefficients (ICCs. We examined the congruent validity of the C-SBEQ by examining the consistency between self-reported and teacher- and classmate-nominated experiences of bullying involvement in Study 2. The results of CFA supported the four-factor structure of the C-SBEQ in Taiwanese adolescents. The test–retest and internal reliability values of all subscales of the C-SBEQ were at acceptable to satisfactory levels. Nominated adolescents had significantly higher self-reported scores on three C-SBEQ subscales than non-nominated ones, and the levels of agreement between self-reported and nominated victims were moderate. The results of this study indicate that the C-SBEQ is appropriate for assessing bullying experiences in Taiwanese adolescents.

  15. The Chinese version of the Pediatric Quality of Life Inventory™ (PedsQL™ 3.0 Asthma Module: reliability and validity

    Directory of Open Access Journals (Sweden)

    Chen Ruoqing

    2011-08-01

    Full Text Available Abstract Background Health-related quality of life (HRQOL has been recognized as an important health outcome measurement for pediatric patients. One of the most promising instruments in measuring pediatric HRQOL emerged in recent years is the Pediatric Quality of Life Inventory (PedsQL™. The PedsQL™ 3.0 Asthma Module, one of the PedsQL™disease-specific scales, was designed to measure HRQOL dimensions specifically tailored for pediatric asthma. The present study is aimed to evaluate the psychometric properties of the Chinese version of the PedsQL™ 3.0 Asthma Module. Methods The PedsQL™ 3.0 Asthma Module was translated into Chinese following the PedsQL™ Measurement Model Translation Methodology. The Chinese version scale was administered to 204 children with asthma and 337 parents of children with asthma from four Triple A hospitals. The psychometric properties were then evaluated. Results The percentage of missing value for each item of the scale ranged from 0.00% to 8.31%. All child self-report subscales and parent proxy-report subscales approached or exceeded the minimum reliability standard of 0.70 for alpha coefficient, except 3 subscales of Young Child (aged 5-7 self-report (alphas ranging from 0.59 to 0.68. Test-retest reliability was satisfactory with intraclass correlation coefficients (ICCs which exceeded the recommended standard of 0.80 in all subscales. Correlation coefficients between items and their hypothesized subscales were higher than those with other subscales. The PedsQL™ 3.0 Asthma Module distinguished between outpatients and inpatients. Patients with mild asthma reported higher scores than those with moderate/severe asthma in majority of subscales. The intercorrelations among the PedsQL™ 3.0 Asthma Module subscales and the PedsQL™ 4.0 Generic Core Scales were in medium to large effect size. The child self-report scores were consistent with the parent proxy-report scores. Conclusions The Chinese version of

  16. An Item Response Analysis of the Motor and Behavioral Subscales of the Unified Huntington's Disease Rating Scale in Huntington Disease Gene Expansion Carriers

    Science.gov (United States)

    Vaccarino, Anthony L.; Anderson, Karen; Borowsky, Beth; Duff, Kevin; Giuliano, Joseph; Guttman, Mark; Ho, Aileen K.; Orth, Michael; Paulsen, Jane S.; Sills, Terrence; van Kammen, Daniel P.; Evans, Kenneth R.

    2011-01-01

    Although the Unified Huntington's Disease Rating Scale (UHDRS) is widely used in the assessment of Huntington disease (HD), the ability of individual items to discriminate individual differences in motor or behavioral manifestations has not been extensively studied in HD gene expansion carriers without a motor-defined clinical diagnosis (i.e., prodromal-HD or prHD). To elucidate the relationship between scores on individual motor and behavioral UHDRS items and total score for each subscale, a non-parametric item response analysis was performed on retrospective data from two multicentre, longitudinal studies. Motor and Behavioral assessments were supplied for 737 prHD individuals with data from 2114 visits (PREDICT-HD) and 686 HD individuals with data from 1482 visits (REGISTRY). Option characteristic curves were generated for UHDRS subscale items in relation to their subscale score. In prHD, overall severity of motor signs was low and participants had scores of 2 or above on very few items. In HD, motor items that assessed ocular pursuit, saccade initiation, finger tapping, tandem walking, and to a lesser extent saccade velocity, dysarthia, tongue protrusion, pronation/supination, Luria, bradykinesia, choreas, gait and balance on the retropulsion test were found to discriminate individual differences across a broad range of motor severity. In prHD, depressed mood, anxiety, and irritable behavior demonstrated good discriminative properties. In HD, depressed mood demonstrated a good relationship with the overall behavioral score. These data suggest that at least some UHDRS items appear to have utility across a broad range of severity, although many items demonstrate problematic features. PMID:21370269

  17. Self-Harm Subscale of the Schedule for Nonadaptive and Adaptive Personality (SNAP): Predicting Suicide Attempts Over 8 Years of Follow-Up

    Science.gov (United States)

    Yen, Shirley; Shea, M. Tracie; Walsh, Zach; Edelen, Maria O.; Hopwood, Christopher J.; Markowitz, John C.; Ansell, Emily B.; Morey, Leslie C.; Grilo, Carlos M.; Sanislow, Charles A.; Skodol, Andrew E.; Gunderson, John G.; Zanarini, Mary C.; McGlashan, Thomas H.

    2013-01-01

    Objective We examined the predictive power of the self-harm subscale of the Schedule for Nonadaptive and Adaptive Personality (SNAP) to identify suicide attempters in the Collaborative Longitudinal Study of Personality Disorders (CLPS). Method The SNAP, a self-report personality inventory, was administered to 733 CLPS participants at baseline, of whom 701 (96%) had at least 6 months of follow-up data. Cox proportional hazards regression analyses were performed to examine the SNAP–self-harm subscale (SNAP-SH) in predicting the 129 suicide attempters over 8 years of follow-up. Possible moderators of prediction were examined, including borderline personality disorder, major depressive disorder (MDD), and substance use disorder. We also compared baseline administration of the SNAP-SH to subsequent administrations more proximal to the suicide attempt, and to a higher-order SNAP-negative temperament (SNAP-NT) subscale. Receiver operating characteristic analyses were conducted using suicide attempts (n = 58) over the first year of follow-up to provide reference points for sensitivity and specificity. Results The SNAP-SH demonstrated good predictive power for suicide attempts (hazard ratio = 1.28, P < .001) and appeared relatively consistent across borderline personality disorder, MDD, and substance use disorder diagnoses. Using more proximal scores did not increase predictive power. The SNAP-SH compared favorably to the predictive power of the higher-order SNAP-NT. Receiver operating characteristic analyses indicate several cutoff scores on the SNAP-SH that yield moderate to high sensitivity and specificity for predicting suicide attempts over the first year of follow-up. Conclusions The SNAP-SH may be a useful screening instrument for risk of suicide attempts in nonpsychotic psychiatric patients. PMID:21294991

  18. Testing comparison models of DASS-12 and its reliability among adolescents in Malaysia.

    Science.gov (United States)

    Osman, Zubaidah Jamil; Mukhtar, Firdaus; Hashim, Hairul Anuar; Abdul Latiff, Latiffah; Mohd Sidik, Sherina; Awang, Hamidin; Ibrahim, Normala; Abdul Rahman, Hejar; Ismail, Siti Irma Fadhilah; Ibrahim, Faisal; Tajik, Esra; Othman, Norlijah

    2014-10-01

    The 21-item Depression, Anxiety and Stress Scale (DASS-21) is frequently used in non-clinical research to measure mental health factors among adults. However, previous studies have concluded that the 21 items are not stable for utilization among the adolescent population. Thus, the aims of this study are to examine the structure of the factors and to report on the reliability of the refined version of the DASS that consists of 12 items. A total of 2850 students (aged 13 to 17 years old) from three major ethnic in Malaysia completed the DASS-21. The study was conducted at 10 randomly selected secondary schools in the northern state of Peninsular Malaysia. The study population comprised secondary school students (Forms 1, 2 and 4) from the selected schools. Based on the results of the EFA stage, 12 items were included in a final CFA to test the fit of the model. Using maximum likelihood procedures to estimate the model, the selected fit indices indicated a close model fit (χ(2)=132.94, df=57, p=.000; CFI=.96; RMR=.02; RMSEA=.04). Moreover, significant loadings of all the unstandardized regression weights implied an acceptable convergent validity. Besides the convergent validity of the item, a discriminant validity of the subscales was also evident from the moderate latent factor inter-correlations, which ranged from .62 to .75. The subscale reliability was further estimated using Cronbach's alpha and the adequate reliability of the subscales was obtained (Total=76; Depression=.68; Anxiety=.53; Stress=.52). The new version of the 12-item DASS for adolescents in Malaysia (DASS-12) is reliable and has a stable factor structure, and thus it is a useful instrument for distinguishing between depression, anxiety and stress. Copyright © 2014 Elsevier Inc. All rights reserved.

  19. Reliability and validity of the Functional Assessment of Chronic Illness Therapy-Palliative care (FACIT-Pal) scale.

    Science.gov (United States)

    Lyons, Kathleen Doyle; Bakitas, Marie; Hegel, Mark T; Hanscom, Brett; Hull, Jay; Ahles, Tim A

    2009-01-01

    The Functional Assessment of Chronic Illness Therapy (FACIT) system provides a general, multidimensional measure of health-related quality of life (FACT-G) that can be augmented with disease or symptom-specific subscales. The 19-item palliative care subscale of the FACIT system has undergone little psychometric evaluation to date. The aim of this paper is to report the internal consistency, factor structure, and construct validity of the instrument using the palliative care subscale (FACIT-Pal). Two hundred fifty-six persons with advanced cancer in a randomized trial testing a palliative care psychoeducational intervention completed the 46-item FACIT-Pal at baseline. Internal consistency was greater than 0.74 for all subscales and the total score. Seventeen of the 19 palliative care subscale items loaded onto the four-factor solution of the established core measure (FACT-G). As hypothesized, total scores were correlated with measures of symptom intensity (r=-0.73, P<0.001) and depression (r=-0.75, P<0.001). The FACIT-Pal was able to discriminate between participants who died within three months of completing the baseline and participants who lived for at least one year after completing the baseline assessment (t=-4.05, P<0.001). The functional well-being subscale discriminated between participants who had a Karnofsky performance score of 70 and below and participants with a Karnofsky performance score of 80 and above (t=3.40, P<0.001). The findings support the internal consistency reliability and validity of the FACIT-Pal as a measure of health-related quality of life for persons with advanced cancer.

  20. MEASUREMENT: ACCOUNTING FOR RELIABILITY IN PERFORMANCE ESTIMATES.

    Science.gov (United States)

    Waterman, Brian; Sutter, Robert; Burroughs, Thomas; Dunagan, W Claiborne

    2014-01-01

    When evaluating physician performance measures, physician leaders are faced with the quandary of determining whether departures from expected physician performance measurements represent a true signal or random error. This uncertainty impedes the physician leader's ability and confidence to take appropriate performance improvement actions based on physician performance measurements. Incorporating reliability adjustment into physician performance measurement is a valuable way of reducing the impact of random error in the measurements, such as those caused by small sample sizes. Consequently, the physician executive has more confidence that the results represent true performance and is positioned to make better physician performance improvement decisions. Applying reliability adjustment to physician-level performance data is relatively new. As others have noted previously, it's important to keep in mind that reliability adjustment adds significant complexity to the production, interpretation and utilization of results. Furthermore, the methods explored in this case study only scratch the surface of the range of available Bayesian methods that can be used for reliability adjustment; further study is needed to test and compare these methods in practice and to examine important extensions for handling specialty-specific concerns (e.g., average case volumes, which have been shown to be important in cardiac surgery outcomes). Moreover, it's important to note that the provider group average as a basis for shrinkage is one of several possible choices that could be employed in practice and deserves further exploration in future research. With these caveats, our results demonstrate that incorporating reliability adjustment into physician performance measurements is feasible and can notably reduce the incidence of "real" signals relative to what one would expect to see using more traditional approaches. A physician leader who is interested in catalyzing performance improvement