WorldWideScience

Sample records for reliability limited life

  1. 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

  2. [Limiting life sustaining therapies].

    Science.gov (United States)

    Azoulay, E

    2006-09-01

    Intensivists are increasingly implementing end-of-life decisions in patients who remain dependent on life sustaining therapies without hope for recovery. Descriptive studies have provided epidemiological data on ICU end-of-life care, identifying areas for improvement. Qualitative studies have highlighted the complexity of the decision making process. In addition to considering the legal and ethical issues involved, this review describes cultural, religious and individual variations observed in ICU end-of-life care. It is important for intensivists to respect patients' preferences and values, but also, in some family members, to avoid increasing the burden and the guilt of sharing the decision. Intensivists should improve their ability to meet the needs of dying patients and their family members. Each situation, patient, family and caregiver is unique, and therefore needs a specific approach. Introducing palliative care and multidisciplinary teams into the ICU might provide an additional opportunity for patients and families to be informed and listened to.

  3. 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.

  4. Reliability of dynamic systems under limited information.

    Energy Technology Data Exchange (ETDEWEB)

    Field, Richard V., Jr. (.,; .); Grigoriu, Mircea

    2006-09-01

    A method is developed for reliability analysis of dynamic systems under limited information. The available information includes one or more samples of the system output; any known information on features of the output can be used if available. The method is based on the theory of non-Gaussian translation processes and is shown to be particularly suitable for problems of practical interest. For illustration, we apply the proposed method to a series of simple example problems and compare with results given by traditional statistical estimators in order to establish the accuracy of the method. It is demonstrated that the method delivers accurate results for the case of linear and nonlinear dynamic systems, and can be applied to analyze experimental data and/or mathematical model outputs. Two complex applications of direct interest to Sandia are also considered. First, we apply the proposed method to assess design reliability of a MEMS inertial switch. Second, we consider re-entry body (RB) component vibration response during normal re-entry, where the objective is to estimate the time-dependent probability of component failure. This last application is directly relevant to re-entry random vibration analysis at Sandia, and may provide insights on test-based and/or model-based qualification of weapon components for random vibration environments.

  5. 76 FR 42534 - Mandatory Reliability Standards for Interconnection Reliability Operating Limits; System...

    Science.gov (United States)

    2011-07-19

    ... Reliability Operating Limits; System Restoration Reliability Standards AGENCY: Federal Energy Regulatory... data necessary to analyze and monitor Interconnection Reliability Operating Limits (IROL) within its... Interconnection Reliability Operating Limits, Order No. 748, 134 FERC ] 61,213 (2011). \\2\\ The term ``Wide-Area...

  6. Overcoming some limitations of imprecise reliability models

    DEFF Research Database (Denmark)

    Kozine, Igor; Krymsky, Victor

    2011-01-01

    The application of imprecise reliability models is often hindered by the rapid growth in imprecision that occurs when many components constitute a system and by the fact that time to failure is bounded from above. The latter results in the necessity to explicitly introduce an upper bound on time ...

  7. Limitation and life in space

    Science.gov (United States)

    Israel, Marvin; Smith, T. Scott

    1986-08-01

    ``The Earth is the very quintescence of the human condition...,'' says Hannah Arendt. Georg Simmel writes: ``The stranger is by nature no `owner of soil'—soil not only in the physical, but also in the figurative sense of a life-substance which is fixed, if not in a point in space, at least in an ideal point of social environment.'' How will no longer being Earthbound affect persons' experience of themselves and of others? Space colonization offers an opportunity for new self-definition by the alteration of existing limits. Thus ``limitation'' is a useful concept for exploring the physical, social and psychological significance of the colonization of space. Will people seek the security of routine, of convention, of hierarchy as in the military model governing our present-day astronauts? or will they seek to maximize the freedom inherent in extraordinary living conditions—as bohemians, deviants, travelers?

  8. Limits of reliability for the measurement of integral count

    International Nuclear Information System (INIS)

    Erbeszkorn, L.

    1979-01-01

    A method is presented for exact and approximate calculation of reliability limits of measured nuclear integral count. The formulae are applicable in measuring conditions which assure the Poisson distribution of the counts. The coefficients of the approximate formulae for 90, 95, 98 and 99 per cent reliability levels are given. The exact reliability limits for 90 per cent reliability level are calculated up to 80 integral counts. (R.J.)

  9. Influences on and Limitations of Classical Test Theory Reliability Estimates.

    Science.gov (United States)

    Arnold, Margery E.

    It is incorrect to say "the test is reliable" because reliability is a function not only of the test itself, but of many factors. The present paper explains how different factors affect classical reliability estimates such as test-retest, interrater, internal consistency, and equivalent forms coefficients. Furthermore, the limits of classical test…

  10. Reliability and extended-life potential of EBR-II

    International Nuclear Information System (INIS)

    King, R.W.

    1985-01-01

    Although the longlife potential of liquid-metal-cooled reactors (LMRs) has been only partially demonstrated, many factors point to the potential for exceptionally long life. EBR-II has the opportunity to become the first LMR to achieve an operational lifetime of 30 years or more. In 1984 a study of the extended-life potential of EBR-II identified the factors that contribute to the continued successful operation of EBR-II as a power reactor and experimental facility. Also identified were factors that could cause disruptions in the useful life of the facility. Although no factors were found that would inherently limit the life of EBR-II, measures were identified that could help ensure continued plant availability. These measures include the implementation of more effective surveillance, diagnostic, and control systems to complement the inherent safety and reliability features of EBR-II. An operating lifetime of well beyond 30 years is certainly feasible

  11. Finite element reliability analysis of fatigue life

    International Nuclear Information System (INIS)

    Harkness, H.H.; Belytschko, T.; Liu, W.K.

    1992-01-01

    Fatigue reliability is addressed by the first-order reliability method combined with a finite element method. Two-dimensional finite element models of components with cracks in mode I are considered with crack growth treated by the Paris law. Probability density functions of the variables affecting fatigue are proposed to reflect a setting where nondestructive evaluation is used, and the Rosenblatt transformation is employed to treat non-Gaussian random variables. Comparisons of the first-order reliability results and Monte Carlo simulations suggest that the accuracy of the first-order reliability method is quite good in this setting. Results show that the upper portion of the initial crack length probability density function is crucial to reliability, which suggests that if nondestructive evaluation is used, the probability of detection curve plays a key role in reliability. (orig.)

  12. Mathematical Methods in Survival Analysis, Reliability and Quality of Life

    CERN Document Server

    Huber, Catherine; Mesbah, Mounir

    2008-01-01

    Reliability and survival analysis are important applications of stochastic mathematics (probability, statistics and stochastic processes) that are usually covered separately in spite of the similarity of the involved mathematical theory. This title aims to redress this situation: it includes 21 chapters divided into four parts: Survival analysis, Reliability, Quality of life, and Related topics. Many of these chapters were presented at the European Seminar on Mathematical Methods for Survival Analysis, Reliability and Quality of Life in 2006.

  13. Scaling limits and reliability of SOI CMOS technology

    International Nuclear Information System (INIS)

    Ioannou, D E

    2005-01-01

    As bulk and PD-SOI CMOS approach their scaling limit (at gate length of around 50 nm), there is a renewed interest on FD-SOI because of its potential for continued scalability beyond this limit. In this review the performance and reliability of extremely scaled FD transistors are discussed and an attempt is made to identify critical areas for further research. (invited paper)

  14. Validity and Reliability of the 8-Item Work Limitations Questionnaire.

    Science.gov (United States)

    Walker, Timothy J; Tullar, Jessica M; Diamond, Pamela M; Kohl, Harold W; Amick, Benjamin C

    2017-12-01

    Purpose To evaluate factorial validity, scale reliability, test-retest reliability, convergent validity, and discriminant validity of the 8-item Work Limitations Questionnaire (WLQ) among employees from a public university system. Methods A secondary analysis using de-identified data from employees who completed an annual Health Assessment between the years 2009-2015 tested research aims. Confirmatory factor analysis (CFA) (n = 10,165) tested the latent structure of the 8-item WLQ. Scale reliability was determined using a CFA-based approach while test-retest reliability was determined using the intraclass correlation coefficient. Convergent/discriminant validity was tested by evaluating relations between the 8-item WLQ with health/performance variables for convergent validity (health-related work performance, number of chronic conditions, and general health) and demographic variables for discriminant validity (gender and institution type). Results A 1-factor model with three correlated residuals demonstrated excellent model fit (CFI = 0.99, TLI = 0.99, RMSEA = 0.03, and SRMR = 0.01). The scale reliability was acceptable (0.69, 95% CI 0.68-0.70) and the test-retest reliability was very good (ICC = 0.78). Low-to-moderate associations were observed between the 8-item WLQ and the health/performance variables while weak associations were observed between the demographic variables. Conclusions The 8-item WLQ demonstrated sufficient reliability and validity among employees from a public university system. Results suggest the 8-item WLQ is a usable alternative for studies when the more comprehensive 25-item WLQ is not available.

  15. Reliability analysis - systematic approach based on limited data

    International Nuclear Information System (INIS)

    Bourne, A.J.

    1975-11-01

    The initial approaches required for reliability analysis are outlined. These approaches highlight the system boundaries, examine the conditions under which the system is required to operate, and define the overall performance requirements. The discussion is illustrated by a simple example of an automatic protective system for a nuclear reactor. It is then shown how the initial approach leads to a method of defining the system, establishing performance parameters of interest and determining the general form of reliability models to be used. The overall system model and the availability of reliability data at the system level are next examined. An iterative process is then described whereby the reliability model and data requirements are systematically refined at progressively lower hierarchic levels of the system. At each stage, the approach is illustrated with examples from the protective system previously described. The main advantages of the approach put forward are the systematic process of analysis, the concentration of assessment effort in the critical areas and the maximum use of limited reliability data. (author)

  16. Developing Reliable Telemedicine Platforms with Unreliable and Limited Communication Bandwidth

    Science.gov (United States)

    2017-10-01

    AFRL-SA-WP-TR-2017-0019 Developing Reliable Telemedicine Platforms with Unreliable and Limited Communication Bandwidth Peter F...Wright-Patterson AFB, OH 45433-7913 DISTRIBUTION STATEMENT A. Approved for public release. Distribution is unlimited. STINFO COPY NOTICE AND...invention that may relate to them. Qualified requestors may obtain copies of this report from the Defense Technical Information Center (DTIC) (http

  17. The thermal limits to life on Earth

    Science.gov (United States)

    Clarke, Andrew

    2014-04-01

    Living organisms on Earth are characterized by three necessary features: a set of internal instructions encoded in DNA (software), a suite of proteins and associated macromolecules providing a boundary and internal structure (hardware), and a flux of energy. In addition, they replicate themselves through reproduction, a process that renders evolutionary change inevitable in a resource-limited world. Temperature has a profound effect on all of these features, and yet life is sufficiently adaptable to be found almost everywhere water is liquid. The thermal limits to survival are well documented for many types of organisms, but the thermal limits to completion of the life cycle are much more difficult to establish, especially for organisms that inhabit thermally variable environments. Current data suggest that the thermal limits to completion of the life cycle differ between the three major domains of life, bacteria, archaea and eukaryotes. At the very highest temperatures only archaea are found with the current high-temperature limit for growth being 122 °C. Bacteria can grow up to 100 °C, but no eukaryote appears to be able to complete its life cycle above ~60 °C and most not above 40 °C. The lower thermal limit for growth in bacteria, archaea, unicellular eukaryotes where ice is present appears to be set by vitrification of the cell interior, and lies at ~-20 °C. Lichens appear to be able to grow down to ~-10 °C. Higher plants and invertebrates living at high latitudes can survive down to ~-70 °C, but the lower limit for completion of the life cycle in multicellular organisms appears to be ~-2 °C.

  18. Imperfect Preventive Maintenance Model Study Based On Reliability Limitation

    Directory of Open Access Journals (Sweden)

    Zhou Qian

    2016-01-01

    Full Text Available Effective maintenance is crucial for equipment performance in industry. Imperfect maintenance conform to actual failure process. Taking the dynamic preventive maintenance cost into account, the preventive maintenance model was constructed by using age reduction factor. The model regards the minimization of repair cost rate as final target. It use allowed smallest reliability as the replacement condition. Equipment life was assumed to follow two parameters Weibull distribution since it was one of the most commonly adopted distributions to fit cumulative failure problems. Eventually the example verifies the rationality and benefits of the model.

  19. Ultra Reliable Closed Loop Life Support for Long Space Missions

    Science.gov (United States)

    Jones, Harry W.; Ewert, Michael K.

    2010-01-01

    Spacecraft human life support systems can achieve ultra reliability by providing sufficient spares to replace all failed components. The additional mass of spares for ultra reliability is approximately equal to the original system mass, provided that the original system reliability is not too low. Acceptable reliability can be achieved for the Space Shuttle and Space Station by preventive maintenance and by replacing failed units. However, on-demand maintenance and repair requires a logistics supply chain in place to provide the needed spares. In contrast, a Mars or other long space mission must take along all the needed spares, since resupply is not possible. Long missions must achieve ultra reliability, a very low failure rate per hour, since they will take years rather than weeks and cannot be cut short if a failure occurs. Also, distant missions have a much higher mass launch cost per kilogram than near-Earth missions. Achieving ultra reliable spacecraft life support systems with acceptable mass will require a well-planned and extensive development effort. Analysis must determine the reliability requirement and allocate it to subsystems and components. Ultra reliability requires reducing the intrinsic failure causes, providing spares to replace failed components and having "graceful" failure modes. Technologies, components, and materials must be selected and designed for high reliability. Long duration testing is needed to confirm very low failure rates. Systems design should segregate the failure causes in the smallest, most easily replaceable parts. The system must be designed, developed, integrated, and tested with system reliability in mind. Maintenance and reparability of failed units must not add to the probability of failure. The overall system must be tested sufficiently to identify any design errors. A program to develop ultra reliable space life support systems with acceptable mass should start soon since it must be a long term effort.

  20. Life prediction and mechanical reliability of NT551 silicon nitride

    Science.gov (United States)

    Andrews, Mark Jay

    551. For the same reasons, the predicted and actual fatigue performance did not correlate well. The results of this study should not be considered a limitation of the life prediction algorithm but emphasize the requirement that ceramics be homogeneous and strength-limiting flaws uniformly distributed as a perquisite for accurate life prediction and reliability analyses.

  1. Limitations in simulator time-based human reliability analysis methods

    International Nuclear Information System (INIS)

    Wreathall, J.

    1989-01-01

    Developments in human reliability analysis (HRA) methods have evolved slowly. Current methods are little changed from those of almost a decade ago, particularly in the use of time-reliability relationships. While these methods were suitable as an interim step, the time (and the need) has come to specify the next evolution of HRA methods. As with any performance-oriented data source, power plant simulator data have no direct connection to HRA models. Errors reported in data are normal deficiencies observed in human performance; failures are events modeled in probabilistic risk assessments (PRAs). Not all errors cause failures; not all failures are caused by errors. Second, the times at which actions are taken provide no measure of the likelihood of failures to act correctly within an accident scenario. Inferences can be made about human reliability, but they must be made with great care. Specific limitations are discussed. Simulator performance data are useful in providing qualitative evidence of the variety of error types and their potential influences on operating systems. More work is required to combine recent developments in the psychology of error with the qualitative data collected at stimulators. Until data become openly available, however, such an advance will not be practical

  2. Developing Ultra Reliable Life Support for the Moon and Mars

    Science.gov (United States)

    Jones, Harry W.

    2009-01-01

    Recycling life support systems can achieve ultra reliability by using spares to replace failed components. The added mass for spares is approximately equal to the original system mass, provided the original system reliability is not very low. Acceptable reliability can be achieved for the space shuttle and space station by preventive maintenance and by replacing failed units, However, this maintenance and repair depends on a logistics supply chain that provides the needed spares. The Mars mission must take all the needed spares at launch. The Mars mission also must achieve ultra reliability, a very low failure rate per hour, since it requires years rather than weeks and cannot be cut short if a failure occurs. Also, the Mars mission has a much higher mass launch cost per kilogram than shuttle or station. Achieving ultra reliable space life support with acceptable mass will require a well-planned and extensive development effort. Analysis must define the reliability requirement and allocate it to subsystems and components. Technologies, components, and materials must be designed and selected for high reliability. Extensive testing is needed to ascertain very low failure rates. Systems design should segregate the failure causes in the smallest, most easily replaceable parts. The systems must be designed, produced, integrated, and tested without impairing system reliability. Maintenance and failed unit replacement should not introduce any additional probability of failure. The overall system must be tested sufficiently to identify any design errors. A program to develop ultra reliable space life support systems with acceptable mass must start soon if it is to produce timely results for the moon and Mars.

  3. Reliability

    OpenAIRE

    Condon, David; Revelle, William

    2017-01-01

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

  4. The Quality of Life Scale (QOLS: Reliability, Validity, and Utilization

    Directory of Open Access Journals (Sweden)

    Anderson Kathryn L

    2003-10-01

    Full Text Available Abstract The Quality of Life Scale (QOLS, created originally by American psychologist John Flanagan in the 1970's, has been adapted for use in chronic illness groups. This paper reviews the development and psychometric testing of the QOLS. A descriptive review of the published literature was undertaken and findings summarized in the frequently asked questions format. Reliability, content and construct validity testing has been performed on the QOLS and a number of translations have been made. The QOLS has low to moderate correlations with physical health status and disease measures. However, content validity analysis indicates that the instrument measures domains that diverse patient groups with chronic illness define as quality of life. The QOLS is a valid instrument for measuring quality of life across patient groups and cultures and is conceptually distinct from health status or other causal indicators of quality of life.

  5. Reliability and service life of wood structures and buildings

    Directory of Open Access Journals (Sweden)

    Zdeňka Havířová

    2005-01-01

    Full Text Available Service life of constructions and buildings of wood is dependent on temperature and moisture conditions in layers of the building cladding where the wood framework is built in. Temperature/moisture conditions or the corresponding equilibrium moisture content (EMC of the construction show considerable effects on the functional reliability of the whole building from the viewpoint of mechanical resistance and stability (ER1, energy savings and thermal protection (ER6 and hygiene, health and environment protection (ER3. To ensure the reliability of constructions and buildings for the period of their supposed service life a more profound analysis of constructions is necessary from the aspect of a global thermal/technical evaluation.

  6. Reliability and service life of wood structures and buildings

    OpenAIRE

    Zdeňka Havířová; Pavel Kubů

    2005-01-01

    Service life of constructions and buildings of wood is dependent on temperature and moisture conditions in layers of the building cladding where the wood framework is built in. Temperature/moisture conditions or the corresponding equilibrium moisture content (EMC) of the construction show considerable effects on the functional reliability of the whole building from the viewpoint of mechanical resistance and stability (ER1), energy savings and thermal protection (ER6) and hygiene, health and e...

  7. Reliability assessment of creep rupture life for Gr. 91 steel

    International Nuclear Information System (INIS)

    Kim, Woo-Gon; Park, Jae-Young; Kim, Seon-Jin; Jang, Jinsung

    2013-01-01

    Highlights: • Statistical analysis of a number of creep rupture data based on Z parameter. • Determination of the constant C in LM parameter and long-term creep life prediction. • Generation of random variables for Z s and Z cr by Monte-Carlo simulation in a SCRI model. • Examples for design application were reasonably drawn from the viewpoints of reliability. - Abstract: This paper presents reliability assessment of the long-term creep life of Gr. 91 steel, which is a major structural material for high temperature structural components of Generation-IV reactor systems. A number of creep rupture data for Gr. 91 steel were collected through literature surveys, and the long-term creep life was predicted by Larson–Miller parameter. A “Z parameter” method was used to describe the magnitude of the deviation of the creep rupture data to a master curve. A “Service Condition-creep Rupture property Interference (SCRI) model” based on the Z parameter was used to simultaneously consider the scattering of the creep rupture data of materials and the fluctuations of service conditions in reliability assessment. A statistical analysis of the creep rupture data was conducted by the Z parameter. To carry out the SCRI model, a number of random variables for Z s describing service conditions and Z cr describing the dispersion of the creep rupture data were generated using a Monte-Carlo simulation technique. As examples for application, the creep rupture life under a certain service conditions of Gr. 91 steel was reasonably drawn from the viewpoints of reliability

  8. Validation and reliability of the Turkish Utian Quality-of-Life Scale in postmenopausal women.

    Science.gov (United States)

    Abay, Halime; Kaplan, Sena

    2016-04-01

    There are a limited number of menopause-specific quality-of-life scales for the Turkish population. This study was conducted to evaluate the validity and reliability of the Turkish Utian Quality-of-Life Scale in postmenopausal women. The study group was comprised of 250 postmenopausal women who applied to a training and research hospital's menopause clinic in Turkey. A survey form and the Turkish Utian quality-of-Life Scale were used to collect data, and the Turkish version of Short Form-36 was used to evaluate reliability with an equivalent form. Language-validity, content-validity, and construct-validity methods were used to assess the validity of the scale, and Cronbach's α coefficient calculation and the equivalent-form reliability methods were used to assess the reliability of the scale. The Turkish Utian Quality-of-Life Scale was determined to be a valid and reliable instrument for measuring the quality of life of postmenopausal women. Confirmatory factor analysis demonstrates that the instrument fits well with 23 items and a four-factor model. The Cronbach's α coefficient for the quality-of-life domains were as follows: 0.88 overall, 0.79 health, 0.78 emotional, 0.76 sexual, and 0.75 occupational. Reliability of the instrument was confirmed through significant correlations between scores on the Turkish version of the Utian Quality-of-Life Scale and the Turkish version of the Short Form-36 (r = 0.745, P measuring quality of life during menopause.

  9. 76 FR 16240 - Mandatory Reliability Standards for Interconnection Reliability Operating Limits

    Science.gov (United States)

    2011-03-23

    ... identified by the Commission. \\5\\ Mandatory Reliability Standards for the Bulk-Power System, Order No. 693... reliability of the interconnection by ensuring that the bulk electric system is assessed during the operations... responsibility for SOLs. Further, Bulk-Power System reliability practices assign responsibilities for analyzing...

  10. Reliability Centered Maintenance as a tool for plant life extension

    International Nuclear Information System (INIS)

    Elliott, J.O.; Mulay, J.N.; Nakahara, Y.

    1991-01-01

    Currently in the nuclear industry there is a growing interest in lowering the cost and complexity of maintenance activities while at the same time improving plant reliability and safety in an effort to prepare for the technical and regulatory challenges of life extension. This seemingly difficult task is being aided by the introduction of a maintenance philosophy developed originally by the airline industry and subsequently applied with great success both in that industry and the U.S. military services. Reliability Centered Maintenance (RCM), in its basic form, may be described as a consideration of reliability and maintenance problems from a systems level approach, allowing a focus on preservation of system function as the aim of a maintenance program optimized for both safety and economics. It is this systematic view of plant maintenance, with the emphasis on overall functions rather than individual parts and components which sets RCM apart from past nuclear plant maintenance philosophies. It is also the factor which makes application of RCM an ideal first step in development of strategies for life extension, both for aging plants, and for plants just beginning their first license term. (J.P.N.)

  11. Steam generator life-management, reliability, maintenance and refurbishment

    International Nuclear Information System (INIS)

    Spekkens, P.

    2012-01-01

    SGC 2012 is a different kind of a conference - it has its own focus, initiatives and objectives and differs from its predecessors. It originated as the Steam Generator and Heat Exchanger Conference in 1990 - a time when premature degradation of steam generators with Alloy 600 tubes was rampant world-wide, and some CANDU steam generators had started to experience significant fouling and corrosion issues. The six previous steam generator conferences were held on a regular cycle, in a very similar format and with a similar theme. We are now in a different era in steam generators. The Alloy 600 tubing has been largely replaced by more robust materials, and the CANDU steam generators have been brought under much more intense and effective life cycle management. Performance of steam generators has improved greatly, and they are no longer considered at risk of limiting the life of the units. Indeed, most Incoloy 800 steam generators in CANDU units are considered to be capable of operating reliably through the 'second life' of the units and are not being replaced during refurbishments. Given this changing environment, the scope of this conference has been expanded from one to three areas: steam generators and heat exchangers as before, but also; controls, valves and pumps, and; reactor components and systems, Programs A, B and C, respectively. The conference is targeting to address the needs and interests of the operating utilities, and to 'focus on what needs attention'. As a means of 'focusing on what needs attention' an 'Issue-Identification and Definition' program was initiated last winter. The Issue-Identification Team operating with COG President Bob Morrison as its Executive Lead, worked to identify issues requiring attention in the three areas of interest. Of the many issues identified by the Team and elaborated on by the Program Developers of this conference, four were recommended for special attention: A. 'Operate Clean - Build Clean - Plant Wide': Despite their

  12. 75 FR 71613 - Mandatory Reliability Standards for Interconnection Reliability Operating Limits

    Science.gov (United States)

    2010-11-24

    ... Interconnection to relieve overloads on the facilities modeled in the Interchange Distribution Calculator (IDC... for other SOLs. But the Functional Model assigns a much broader role to the reliability coordinator to...

  13. Application of structural reliability and risk assessment to life prediction and life extension decision making

    International Nuclear Information System (INIS)

    Meyer, T.A.; Balkey, K.R.; Bishop, B.A.

    1987-01-01

    There can be numerous uncertainties involved in performing component life assessments. In addition, sufficient data may be unavailable to make a useful life prediction. Structural Reliability and Risk Assessment (SRRA) is primarily an analytical methodology or tool that quantifies the impact of uncertainties on the structural life of plant components and can address the lack of data in component life prediction. As a prelude to discussing the technical aspects of SRRA, a brief review of general component life prediction methods is first made so as to better develop an understanding of the role of SRRA in such evaluations. SRRA is then presented as it is applied in component life evaluations with example applications being discussed for both nuclear and non-nuclear components

  14. Limits on reliable information flows through stochastic populations.

    Science.gov (United States)

    Boczkowski, Lucas; Natale, Emanuele; Feinerman, Ofer; Korman, Amos

    2018-06-06

    Biological systems can share and collectively process information to yield emergent effects, despite inherent noise in communication. While man-made systems often employ intricate structural solutions to overcome noise, the structure of many biological systems is more amorphous. It is not well understood how communication noise may affect the computational repertoire of such groups. To approach this question we consider the basic collective task of rumor spreading, in which information from few knowledgeable sources must reliably flow into the rest of the population. We study the effect of communication noise on the ability of groups that lack stable structures to efficiently solve this task. We present an impossibility result which strongly restricts reliable rumor spreading in such groups. Namely, we prove that, in the presence of even moderate levels of noise that affect all facets of the communication, no scheme can significantly outperform the trivial one in which agents have to wait until directly interacting with the sources-a process which requires linear time in the population size. Our results imply that in order to achieve efficient rumor spread a system must exhibit either some degree of structural stability or, alternatively, some facet of the communication which is immune to noise. We then corroborate this claim by providing new analyses of experimental data regarding recruitment in Cataglyphis niger desert ants. Finally, in light of our theoretical results, we discuss strategies to overcome noise in other biological systems.

  15. Reliable tool life measurements in turning - an application to cutting fluid efficiency evaluation

    DEFF Research Database (Denmark)

    Axinte, Dragos A.; Belluco, Walter; De Chiffre, Leonardo

    2001-01-01

    The paper proposes a method to obtain reliable measurements of tool life in turning, discussing some aspects related to experimental procedure and measurement accuracy. The method (i) allows and experimental determination of the extended Taylor's equation, with a limited set of experiments and (ii......) provides efficiency evaluation. Six cutting oils, five of which formulated from vegetable basestock, were evaluated in turning. Experiments were run in a range of cutting parameters. according to a 2, 3-1 factorial design, machining AISI 316L stainless steel with coated carbide tools. Tool life...

  16. An Energy-Based Limit State Function for Estimation of Structural Reliability in Shock Environments

    Directory of Open Access Journals (Sweden)

    Michael A. Guthrie

    2013-01-01

    Full Text Available limit state function is developed for the estimation of structural reliability in shock environments. This limit state function uses peak modal strain energies to characterize environmental severity and modal strain energies at failure to characterize the structural capacity. The Hasofer-Lind reliability index is briefly reviewed and its computation for the energy-based limit state function is discussed. Applications to two degree of freedom mass-spring systems and to a simple finite element model are considered. For these examples, computation of the reliability index requires little effort beyond a modal analysis, but still accounts for relevant uncertainties in both the structure and environment. For both examples, the reliability index is observed to agree well with the results of Monte Carlo analysis. In situations where fast, qualitative comparison of several candidate designs is required, the reliability index based on the proposed limit state function provides an attractive metric which can be used to compare and control reliability.

  17. Space Shuttle Rudder Speed Brake Actuator-A Case Study Probabilistic Fatigue Life and Reliability Analysis

    Science.gov (United States)

    Oswald, Fred B.; Savage, Michael; Zaretsky, Erwin V.

    2015-01-01

    The U.S. Space Shuttle fleet was originally intended to have a life of 100 flights for each vehicle, lasting over a 10-year period, with minimal scheduled maintenance or inspection. The first space shuttle flight was that of the Space Shuttle Columbia (OV-102), launched April 12, 1981. The disaster that destroyed Columbia occurred on its 28th flight, February 1, 2003, nearly 22 years after its first launch. In order to minimize risk of losing another Space Shuttle, a probabilistic life and reliability analysis was conducted for the Space Shuttle rudder/speed brake actuators to determine the number of flights the actuators could sustain. A life and reliability assessment of the actuator gears was performed in two stages: a contact stress fatigue model and a gear tooth bending fatigue model. For the contact stress analysis, the Lundberg-Palmgren bearing life theory was expanded to include gear-surface pitting for the actuator as a system. The mission spectrum of the Space Shuttle rudder/speed brake actuator was combined into equivalent effective hinge moment loads including an actuator input preload for the contact stress fatigue and tooth bending fatigue models. Gear system reliabilities are reported for both models and their combination. Reliability of the actuator bearings was analyzed separately, based on data provided by the actuator manufacturer. As a result of the analysis, the reliability of one half of a single actuator was calculated to be 98.6 percent for 12 flights. Accordingly, each actuator was subsequently limited to 12 flights before removal from service in the Space Shuttle.

  18. Teachers Communicating about Life-Limiting Conditions, Death and Bereavement

    Science.gov (United States)

    Robinson, Sally; Ekins, Alison; Durrant, Ian; Summers, Kathryn

    2018-01-01

    The number of children with life-limiting or life-threatening conditions in England is double what it was at the millennium. These conditions include cystic fibrosis, cancer, organ failure and severe neurological injuries. The Teaching for Life project aimed to explore the needs of teachers working in English schools in relation to working with…

  19. Reliability Evaluation of Bridges Based on Nonprobabilistic Response Surface Limit Method

    OpenAIRE

    Chen, Xuyong; Chen, Qian; Bian, Xiaoya; Fan, Jianping

    2017-01-01

    Due to many uncertainties in nonprobabilistic reliability assessment of bridges, the limit state function is generally unknown. The traditional nonprobabilistic response surface method is a lengthy and oscillating iteration process and leads to difficultly solving the nonprobabilistic reliability index. This article proposes a nonprobabilistic response surface limit method based on the interval model. The intention of this method is to solve the upper and lower limits of the nonprobabilistic ...

  20. Applications of majorization and Schur functions in reliability and life testing

    International Nuclear Information System (INIS)

    Proschan, F.

    1975-01-01

    This is an expository paper presenting basic definitions and properties of majorization and Schur functions, and displaying a variety of applications of these concepts in reliability prediction and modelling, and in reliability inference and life testing

  1. Reliability Evaluation of Bridges Based on Nonprobabilistic Response Surface Limit Method

    Directory of Open Access Journals (Sweden)

    Xuyong Chen

    2017-01-01

    Full Text Available Due to many uncertainties in nonprobabilistic reliability assessment of bridges, the limit state function is generally unknown. The traditional nonprobabilistic response surface method is a lengthy and oscillating iteration process and leads to difficultly solving the nonprobabilistic reliability index. This article proposes a nonprobabilistic response surface limit method based on the interval model. The intention of this method is to solve the upper and lower limits of the nonprobabilistic reliability index and to narrow the range of the nonprobabilistic reliability index. If the range of the reliability index reduces to an acceptable accuracy, the solution will be considered convergent, and the nonprobabilistic reliability index will be obtained. The case study indicates that using the proposed method can avoid oscillating iteration process, make iteration process stable and convergent, reduce iteration steps significantly, and improve computational efficiency and precision significantly compared with the traditional nonprobabilistic response surface method. Finally, the nonprobabilistic reliability evaluation process of bridge will be built through evaluating the reliability of one PC continuous rigid frame bridge with three spans using the proposed method, which appears to be more simple and reliable when lack of samples and parameters in the bridge nonprobabilistic reliability evaluation is present.

  2. A study on the reliability evaluation of shot peened aluminium alloy using accelerated life test

    International Nuclear Information System (INIS)

    Nam, Ji Hun; Cheong, Seong Kyun; Kang, Min Woo

    2006-01-01

    In this paper, the concept of accelerated life test, which is a popular research field nowadays, is applied to the shot peened material. To predict the efficient and exact room temperature fatigue characteristics from the high temperature fatigue data, the adequate accelerated model is investigated. Ono type rotary bending fatigue tester and high temperature chamber were used for the experiment. Room temperature fatigue lives were predicted by applying accelerated models and doing reliability evaluation. Room temperature fatigue tests were accomplished to check the effectiveness of predicted data and the adequate accelerated life test models were presented by considering errors. Experimental result using Arrhenius model, fatigue limit obtain almost 5.45% of error, inverse power law has about 1.36% of error, so we found that inverse power law is applied well to temperature-life relative of shot peended material

  3. [Expectation of life at birth: sex differentials, trends, limits].

    Science.gov (United States)

    Aubenque, M; Damiani, P

    1981-01-01

    Using information available at the end of 1979, the authors present and analyze data on expectation of life at birth in 119 countries. Differences between developing and developed countries, trends over time, sex differentials, and limits on life expectancy are examined. The analysis reveals limits of approximately 73 years for men and 80 for women in the most developed countries. In France, which displays excessive male mortality, expectation of life increases more slowly for men. The authors attribute these sex differentials both to biological factors and to behavioral factors and ways of life.

  4. Treating Chronically Ill Diabetic Patients with Limited Life Expectancy: Implications for Performance Measurement

    Science.gov (United States)

    Woodard, LeChauncy D.; Landrum, Cassie R.; Urech, Tracy H.; Profit, Jochen; Virani, Salim S.; Petersen, Laura A.

    2012-01-01

    Background/Objectives To validly assess quality-of-care differences among providers, performance measurement programs must reliably identify and exclude patients for whom the quality indicator may not be desirable, including those with limited life expectancy. We developed an algorithm to identify patients with limited life expectancy and examined the impact of limited life expectancy on glycemic control and treatment intensification among diabetic patients. Design We identified diabetic patients with coexisting congestive heart failure, chronic obstructive pulmonary disease, dementia, end-stage liver disease, and/or primary/metastatic cancers with limited life expectancy. To validate our algorithm, we assessed 5-year mortality among patients identified as having limited life expectancy. We compared rates of meeting performance measures for glycemic control between patients with and without limited life expectancy. Among uncontrolled patients, we examined the impact of limited life expectancy on treatment intensification within 90 days. Setting 110 Veterans Administration facilities; October 2006 – September 2007 Participants 888,628 diabetic patients Measurements Hemoglobin A1c (HbA1c) Quality measurement and performance-based reimbursement systems should acknowledge the different needs of this population. PMID:22260627

  5. Reliability-based Assessment of Fatigue Life for Bridges

    DEFF Research Database (Denmark)

    Toft, Henrik Stensgaard; Sørensen, John Dalsgaard

    2012-01-01

    The reliability level for bridges is discussed based on a comparison of the reliability levels proposed and used by e.g. JCSS, ISO, NKB and Eurocodes. The influence of reserve capacity by which failure of a specific detail does not lead to structural collapse is investigated. The results show...

  6. Possibilities and limitations of applying software reliability growth models to safety-critical software

    International Nuclear Information System (INIS)

    Kim, Man Cheol; Jang, Seung Cheol; Ha, Jae Joo

    2007-01-01

    It is generally known that software reliability growth models such as the Jelinski-Moranda model and the Goel-Okumoto's Non-Homogeneous Poisson Process (NHPP) model cannot be applied to safety-critical software due to a lack of software failure data. In this paper, by applying two of the most widely known software reliability growth models to sample software failure data, we demonstrate the possibility of using the software reliability growth models to prove the high reliability of safety-critical software. The high sensitivity of a piece of software's reliability to software failure data, as well as a lack of sufficient software failure data, is also identified as a possible limitation when applying the software reliability growth models to safety-critical software

  7. Caring for children with life-limiting and life-threatening illnesses ...

    African Journals Online (AJOL)

    2011-07-03

    Jul 3, 2011 ... She currently works with funding support from the Red Cross War Memorial Children's Hospital and the ... Children with life-limiting illnesses may also develop life-threatening ... bodies in an age-appropriate manner a basic.

  8. Possibilities and Limitations of Applying Software Reliability Growth Models to Safety- Critical Software

    International Nuclear Information System (INIS)

    Kim, Man Cheol; Jang, Seung Cheol; Ha, Jae Joo

    2006-01-01

    As digital systems are gradually introduced to nuclear power plants (NPPs), the need of quantitatively analyzing the reliability of the digital systems is also increasing. Kang and Sung identified (1) software reliability, (2) common-cause failures (CCFs), and (3) fault coverage as the three most critical factors in the reliability analysis of digital systems. For the estimation of the safety-critical software (the software that is used in safety-critical digital systems), the use of Bayesian Belief Networks (BBNs) seems to be most widely used. The use of BBNs in reliability estimation of safety-critical software is basically a process of indirectly assigning a reliability based on various observed information and experts' opinions. When software testing results or software failure histories are available, we can use a process of directly estimating the reliability of the software using various software reliability growth models such as Jelinski- Moranda model and Goel-Okumoto's nonhomogeneous Poisson process (NHPP) model. Even though it is generally known that software reliability growth models cannot be applied to safety-critical software due to small number of expected failure data from the testing of safety-critical software, we try to find possibilities and corresponding limitations of applying software reliability growth models to safety critical software

  9. Life cycle reliability assessment of new products—A Bayesian model updating approach

    International Nuclear Information System (INIS)

    Peng, Weiwen; Huang, Hong-Zhong; Li, Yanfeng; Zuo, Ming J.; Xie, Min

    2013-01-01

    The rapidly increasing pace and continuously evolving reliability requirements of new products have made life cycle reliability assessment of new products an imperative yet difficult work. While much work has been done to separately estimate reliability of new products in specific stages, a gap exists in carrying out life cycle reliability assessment throughout all life cycle stages. We present a Bayesian model updating approach (BMUA) for life cycle reliability assessment of new products. Novel features of this approach are the development of Bayesian information toolkits by separately including “reliability improvement factor” and “information fusion factor”, which allow the integration of subjective information in a specific life cycle stage and the transition of integrated information between adjacent life cycle stages. They lead to the unique characteristics of the BMUA in which information generated throughout life cycle stages are integrated coherently. To illustrate the approach, an application to the life cycle reliability assessment of a newly developed Gantry Machining Center is shown

  10. Requirements and limits for life in the context of exoplanets

    Science.gov (United States)

    McKay, Christopher P.

    2014-09-01

    The requirements for life on Earth, its elemental composition, and its environmental limits provide a way to assess the habitability of exoplanets. Temperature is key both because of its influence on liquid water and because it can be directly estimated from orbital and climate models of exoplanetary systems. Life can grow and reproduce at temperatures as low as -15 °C, and as high as 122 °C. Studies of life in extreme deserts show that on a dry world, even a small amount of rain, fog, snow, and even atmospheric humidity can be adequate for photosynthetic production producing a small but detectable microbial community. Life is able to use light at levels less than 10-5 of the solar flux at Earth. UV or ionizing radiation can be tolerated by many microorganisms at very high levels and is unlikely to be life limiting on an exoplanet. Biologically available nitrogen may limit habitability. Levels of O2 over a few percent on an exoplanet would be consistent with the presence of multicellular organisms and high levels of O2 on Earth-like worlds indicate oxygenic photosynthesis. Other factors such as pH and salinity are likely to vary and not limit life over an entire planet or moon.

  11. What influences parents' decisions to limit or withdraw life support?

    Science.gov (United States)

    Sharman, Mahesh; Meert, Kathleen L; Sarnaik, Ashok P

    2005-09-01

    Decisions to forgo life support from critically ill children are commonly faced by parents and physicians. Previous research regarding parents' perspectives on the decision-making process has been limited by retrospective methods and the use of closed-ended questionnaires. We prospectively identified and described parents' self-reported influences on decisions to forgo life support from their children. Deeper understanding of parents' views will allow physicians to focus end-of-life discussions on factors important to parents and help resolve conflicts. Prospective, qualitative pilot study. Pediatric intensive care unit of a university-affiliated children's hospital. A total of 14 parents of ten children whose pediatric intensive care unit physician had made a recommendation to limit or withdraw life support. : In-depth, semistructured interviews were conducted with parents during their decision-making process. Factors influencing the parents in this study in their decision to forgo life support included their previous experience with death and end-of-life decision making for others, their personal observations of their child's suffering, their perceptions of their child's will to survive, their need to protect and advocate for their child, and the family's financial resources and concerns regarding life-long care. Parents in this study expressed the desire to do what is best for their child but struggled with feelings of selfishness, guilt, and the need to avoid agony and sorrow. Physician recommendations, review of options, and joint formulation of a plan helped parents gain a sense of control over their situation. Parents of eight children agreed to forgo life support and parents of two did not. Prospective interviews with open-ended questions identified factors influencing parents' decision making not previously described in the critical care literature such as parents' past experiences with end-of-life decisions and their anticipated emotional adjustments and

  12. Wealth in Middle and Later Life: Examining the Life Course Timing of Women's Health Limitations.

    Science.gov (United States)

    Wilkinson, Lindsay R; Ferraro, Kenneth F; Mustillo, Sarah A

    2018-06-04

    Guided by cumulative inequality theory, this study poses two main questions: (a) Does women's poor health compromise household financial assets? (b) If yes, is wealth sensitive to the timing of women's health limitations? In addressing these questions, we consider the effect of health limitations on wealth at older ages, as well as examine how health limitations influence wealth over particular segments of the life course, giving attention to both the onset and duration of health limitations. Using 36 years of data from the National Longitudinal Survey of Mature Women, piecewise growth curve and linear regression models were used to estimate the effects of life course timing and duration of health limitations on household wealth. The findings reveal that women who experienced health limitations accumulated substantially less wealth over time, especially if the health limitations were manifest during childhood or early adulthood. This study identifies how early-life health problems lead to less wealth in later life.

  13. Water Walls: Highly Reliable and Massively Redundant Life Support Architecture

    Data.gov (United States)

    National Aeronautics and Space Administration — WATER WALLS (WW) takes an approach to providing a life support system, Forward Osmosis (FO), that is biologically and chemically passive, using mechanical systems...

  14. Constitutional and legal protection for life support limitation in India

    Directory of Open Access Journals (Sweden)

    R K Mani

    2015-01-01

    Full Text Available Appropriate treatment limitations towards the end of life to reduce unwanted burdens require ethical clarity that is supported by appropriate legislation. The lack of knowledge of enabling legal provisions, physicians feel vulnerable to legal misinterpretation of treatment limiting decisions. In India the lack of societal awareness, inadequate exploration of the gray areas of bio-ethics and unambiguous legal position relating to terminal illness have resulted in poor quality end of life care. Much of the perceived vulnerability by the physician is attributable to insufficient knowledge and understanding of existing constitutional and legal position in India. While we await informed legal and legislative opinion, this paper highlights possible legal liabilities arising from treatment limitation decisions with available defense. It is hoped that such clarity would lead to more confident ethical decisions and improved end of life care for patients.

  15. Stress Rupture Life Reliability Measures for Composite Overwrapped Pressure Vessels

    Science.gov (United States)

    Murthy, Pappu L. N.; Thesken, John C.; Phoenix, S. Leigh; Grimes-Ledesma, Lorie

    2007-01-01

    Composite Overwrapped Pressure Vessels (COPVs) are often used for storing pressurant gases onboard spacecraft. Kevlar (DuPont), glass, carbon and other more recent fibers have all been used as overwraps. Due to the fact that overwraps are subjected to sustained loads for an extended period during a mission, stress rupture failure is a major concern. It is therefore important to ascertain the reliability of these vessels by analysis, since the testing of each flight design cannot be completed on a practical time scale. The present paper examines specifically a Weibull statistics based stress rupture model and considers the various uncertainties associated with the model parameters. The paper also examines several reliability estimate measures that would be of use for the purpose of recertification and for qualifying flight worthiness of these vessels. Specifically, deterministic values for a point estimate, mean estimate and 90/95 percent confidence estimates of the reliability are all examined for a typical flight quality vessel under constant stress. The mean and the 90/95 percent confidence estimates are computed using Monte-Carlo simulation techniques by assuming distribution statistics of model parameters based also on simulation and on the available data, especially the sample sizes represented in the data. The data for the stress rupture model are obtained from the Lawrence Livermore National Laboratories (LLNL) stress rupture testing program, carried out for the past 35 years. Deterministic as well as probabilistic sensitivities are examined.

  16. The Physical, Chemical and Physiological Limits of Life

    Directory of Open Access Journals (Sweden)

    Dirk Schulze-Makuch

    2015-07-01

    Full Text Available Life on Earth displays an incredible diversity in form and function, which allows it to survive not only physical extremes, but also periods of time when it is exposed to non-habitable conditions. Extreme physiological adaptations to bridge non-habitable conditions include various dormant states, such as spores or tuns. Here, we advance the hypothesis that if the environmental conditions are different on some other planetary body, a deviating biochemistry would evolve with types of adaptations that would manifest themselves with different physical and chemical limits of life. In this paper, we discuss two specific examples: putative life on a Mars-type planet with a hydrogen peroxide-water solvent and putative life on a Titan-type planetary body with liquid hydrocarbons as a solvent. Both examples would have the result of extending the habitable envelope of life in the universe.

  17. Reliability Reporting Practices in Youth Life Satisfaction Research

    Science.gov (United States)

    Vassar, Matt; Hale, William

    2007-01-01

    Due to the emergence of positive psychology in recent years, a growing line of research has focused on aspects of psychological wellness rather than psychopathology. Within the context of positive psychology, life satisfaction has emerged as a key variable of study in relation to adult and youth populations. Accurate measurement of life…

  18. Trips and the Life Sciences - Perspectives on Limitations to Patentability

    DEFF Research Database (Denmark)

    Wested, Jakob; Minssen, Timo

    2017-01-01

    This report is based on the material and input that was presented and discussed at the webinar with the title: “Perspectives on limitations to patentability”. The Webinar and the theme where introduced by Prof. Timo Minssen. Then Prof. Nari Lee gave a presentation introducing some of the context ...... and Minssen, Timo, Trips and the Life Sciences - Perspectives on Limitations to Patentability (June 15, 2017). Available at SSRN: https://ssrn.com/abstract=2986751...

  19. Evolution of Machine Reliability and Life and Economics of Operational Use

    Directory of Open Access Journals (Sweden)

    Młynarski Stanisław

    2016-12-01

    Full Text Available The article presents new assumptions for reliability and life of machines, resulting from the development of technology. The innovative approach to reliability and life design as well as warranty duration planning is presented on an example of vehicle reliability characteristics. A new algorithm is proposed for the replacement of repairable objects costs by the price of life and reliability of new unrepairable ones. For the planning of the life of innovative machines, an effective method of technical progress rate determination is proposed. In conclusion, necessary modifications of machine and vehicle use systems, resulting from technology evolution and technical progress, are indicated. Finally, recommendations and directions of indispensable research in engineering and management of technical means of production are formulated.

  20. A Note on the Score Reliability for the Satisfaction with Life Scale: An RG Study

    Science.gov (United States)

    Vassar, Matt

    2008-01-01

    The purpose of the present study was to meta-analytically investigate the score reliability for the Satisfaction With Life Scale. Four-hundred and sixteen articles using the measure were located through electronic database searches and then separated to identify studies which had calculated reliability estimates from their own data. Sixty-two…

  1. Life Satisfaction Questionnaire (Lisat-9): Reliability and Validity for Patients with Acquired Brain Injury

    Science.gov (United States)

    Boonstra, Anne M.; Reneman, Michiel F.; Stewart, Roy E.; Balk, Gerlof A.

    2012-01-01

    The aim of this study was to determine the reliability and discriminant validity of the Dutch version of the life satisfaction questionnaire (Lisat-9 DV) to assess patients with an acquired brain injury. The reliability study used a test-retest design, and the validity study used a cross-sectional design. The setting was the general rehabilitation…

  2. Reliability analysis of component-level redundant topologies for solid-state fault current limiter

    Science.gov (United States)

    Farhadi, Masoud; Abapour, Mehdi; Mohammadi-Ivatloo, Behnam

    2018-04-01

    Experience shows that semiconductor switches in power electronics systems are the most vulnerable components. One of the most common ways to solve this reliability challenge is component-level redundant design. There are four possible configurations for the redundant design in component level. This article presents a comparative reliability analysis between different component-level redundant designs for solid-state fault current limiter. The aim of the proposed analysis is to determine the more reliable component-level redundant configuration. The mean time to failure (MTTF) is used as the reliability parameter. Considering both fault types (open circuit and short circuit), the MTTFs of different configurations are calculated. It is demonstrated that more reliable configuration depends on the junction temperature of the semiconductor switches in the steady state. That junction temperature is a function of (i) ambient temperature, (ii) power loss of the semiconductor switch and (iii) thermal resistance of heat sink. Also, results' sensitivity to each parameter is investigated. The results show that in different conditions, various configurations have higher reliability. The experimental results are presented to clarify the theory and feasibility of the proposed approaches. At last, levelised costs of different configurations are analysed for a fair comparison.

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

    Science.gov (United States)

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

    2018-01-01

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

  4. A summary of methods of predicting reliability life of nuclear equipment with small samples

    International Nuclear Information System (INIS)

    Liao Weixian

    2000-03-01

    Some of nuclear equipment are manufactured in small batch, e.g., 1-3 sets. Their service life may be very difficult to determine experimentally in view of economy and technology. The method combining theoretical analysis with material tests to predict the life of equipment is put forward, based on that equipment consists of parts or elements which are made of different materials. The whole life of an equipment part consists of the crack forming life (i.e., the fatigue life or the damage accumulation life) and the crack extension life. Methods of predicting machine life has systematically summarized with the emphasis on those which use theoretical analysis to substitute large scale prototype experiments. Meanwhile, methods and steps of predicting reliability life have been described by taking into consideration of randomness of various variables and parameters in engineering. Finally, the latest advance and trends of machine life prediction are discussed

  5. Reliability and life-cycle analysis of deteriorating systems

    CERN Document Server

    Sánchez-Silva, Mauricio

    2016-01-01

    This book compiles and critically discusses modern engineering system degradation models and their impact on engineering decisions. In particular, the authors focus on modeling the uncertain nature of degradation considering both conceptual discussions and formal mathematical formulations. It also describes the basics concepts and the various modeling aspects of life-cycle analysis (LCA).  It highlights the role of degradation in LCA and defines optimum design and operation parameters. Given the relationship between operational decisions and the performance of the system’s condition over time, maintenance models are also discussed. The concepts and models presented have applications in a large variety of engineering fields such as Civil, Environmental, Industrial, Electrical and Mechanical engineering. However, special emphasis is given to problems related to large infrastructure systems. The book is intended to be used both as a reference resource for researchers and practitioners and as an academic text ...

  6. Reliability Evaluation on Creep Life Prediction of Alloy 617 for a Very High Temperature Reactor

    International Nuclear Information System (INIS)

    Kim, Woo-Gon; Hong, Sung-Deok; Kim, Yong-Wan; Park, Jae-Young; Kim, Seon-Jin

    2012-01-01

    This paper evaluates the reliability of creep rupture life under service conditions of Alloy 617, which is considered as one of the candidate materials for use in a very high temperature reactor (VHTR) system. A Z-parameter, which represents the deviation of creep rupture data from the master curve, was used for the reliability analysis of the creep rupture data of Alloy 617. A Service-condition Creep Rupture Interference (SCRI) model, which can consider both the scattering of the creep rupture data and the fluctuations of temperature and stress under any service conditions, was also used for evaluating the reliability of creep rupture life. The statistical analysis showed that the scattering of creep rupture data based on Z-parameter was supported by normal distribution. The values of reliability decreased rapidly with increasing amplitudes of temperature and stress fluctuations. The results established that the reliability decreased with an increasing service time.

  7. Pre-Proposal Assessment of Reliability for Spacecraft Docking with Limited Information

    Science.gov (United States)

    Brall, Aron

    2013-01-01

    This paper addresses the problem of estimating the reliability of a critical system function as well as its impact on the system reliability when limited information is available. The approach addresses the basic function reliability, and then the impact of multiple attempts to accomplish the function. The dependence of subsequent attempts on prior failure to accomplish the function is also addressed. The autonomous docking of two spacecraft was the specific example that generated the inquiry, and the resultant impact on total reliability generated substantial interest in presenting the results due to the relative insensitivity of overall performance to basic function reliability and moderate degradation given sufficient attempts to try and accomplish the required goal. The application of the methodology allows proper emphasis on the characteristics that can be estimated with some knowledge, and to insulate the integrity of the design from those characteristics that can't be properly estimated with any rational value of uncertainty. The nature of NASA's missions contains a great deal of uncertainty due to the pursuit of new science or operations. This approach can be applied to any function where multiple attempts at success, with or without degradation, are allowed.

  8. A New Approach for Reliability Life Prediction of Rail Vehicle Axle by Considering Vibration Measurement

    Directory of Open Access Journals (Sweden)

    Meral Bayraktar

    2014-01-01

    Full Text Available The effect of vibration on the axle has been considered. Vibration measurements at different speeds have been performed on the axle of a running rail vehicle to figure out displacement, acceleration, time, and frequency response. Based on the experimental works, equivalent stress has been used to find out life of the axles for 90% and 10% reliability. Calculated life values of the rail vehicle axle have been compared with the real life data and it is found that the life of a vehicle axle taking into account the vibration effects is in good agreement with the real life of the axle.

  9. Work limitations among working persons with rheumatoid arthritis: results, reliability, and validity of the work limitations questionnaire in 836 patients.

    Science.gov (United States)

    Walker, Nancy; Michaud, Kaleb; Wolfe, Frederick

    2005-06-01

    To describe workplace limitations and the validity and reliability of the Work Limitations Questionnaire (WLQ) in persons with rheumatoid arthritis (RA). A total of 836 employed persons with RA reported clinical and work related measures and completed the WLQ, a 25 item questionnaire that assesses the impact of chronic health conditions on job performance and productivity. Limitations are categorized into 4 domains: physical demands (PDS), mental demands (MDS), time management demands (TMS), and output demands (ODS), which are then used to calculate the WLQ index. Of the 836 completed WLQ, about 10% (85) could not be scored, as more than half the items in each domain were not applicable to the patient's job. Demographic and clinical variables were associated with missing WLQ scores including older age (OR 1.7, 95% CI 1.3-2.1), male sex (OR 1.9, 95% CI 1.2-3.0), and Health Assessment Questionnaire (HAQ) scores (OR 1.4, 95% CI 1.0-2.0). Work limitations were present in all work domains: PDS (27.5%), MDS (15.7%), ODS (19.4%), and TMS (28.6%), resulting in a mean WLQ index of 5.9 (SD 5.6), which corresponds to a 4.9% decrease in productivity and a 5.1% increase in work hours to compensate for productivity loss. The WLQ index was inversely associated with Medical Outcomes Study Short Form 36 (SF-36) Mental Component Score (MCS; r = -0.60) and Physical Component Score (PCS; r = -0.49). Fatigue (0.5), pain (0.46), and HAQ (0.56) were also significantly associated with the WLQ index. Weaker associations were seen with days unable to perform (0.29), days activities cut down (0.38), and annual income (-0.10). The WLQ is a reliable tool for assessing work productivity. However, persons with RA tend to select jobs that they can do with their RA limitations, with the result that the WLQ does not detect functional limitations as well as the HAQ and SF-36. The WLQ provides special information that is not available using conventional measures of assessment, and can provide helpful

  10. Reliability of buildings in service limit state for maximum horizontal displacements

    Directory of Open Access Journals (Sweden)

    A. G. B. Corelhano

    Full Text Available Brazilian design code ABNT NBR6118:2003 - Design of Concrete Structures - Procedures - [1] proposes the use of simplified models for the consideration of non-linear material behavior in the evaluation of horizontal displacements in buildings. These models penalize stiffness of columns and beams, representing the effects of concrete cracking and avoiding costly physical non-linear analyses. The objectives of the present paper are to investigate the accuracy and uncertainty of these simplified models, as well as to evaluate the reliabilities of structures designed following ABNT NBR6118:2003[1&] in the service limit state for horizontal displacements. Model error statistics are obtained from 42 representative plane frames. The reliabilities of three typical (4, 8 and 12 floor buildings are evaluated, using the simplified models and a rigorous, physical and geometrical non-linear analysis. Results show that the 70/70 (column/beam stiffness reduction model is more accurate and less conservative than the 80/40 model. Results also show that ABNT NBR6118:2003 [1] design criteria for horizontal displacement limit states (masonry damage according to ACI 435.3R-68(1984 [10] are conservative, and result in reliability indexes which are larger than those recommended in EUROCODE [2] for irreversible service limit states.

  11. Limits on quality of life in communication after total laryngectomy.

    Science.gov (United States)

    Chaves, Adriana Di Donato; Pernambuco, Leandro de Araújo; Balata, Patrícia Maria Mendes; Santos, Veridiana da Silva; de Lima, Leilane Maria; de Souza, Síntia Ribeiro; da Silva, Hilton Justino

    2012-10-01

     Among people affected by cancer, the impairment of quality of life of people affected by cancer can cause have devastating effects. The self-image of patients after post-laryngectomyzed patients may be find themselves compromised, affecting the quality of life in this population.  To characterize quality of life in related to communication in people who have undergone went total laryngectomy surgery.  This is an observational study, with a cross-sectional and descriptive series. Design of series study. The sample were comprised 15 patients interviewed the period from January to February of 2011. We used the Quality Protocol for Life Communication in Post-laryngectomy adapted from Bertocello (2004); which this questionnaire contains 55 questions. The protocol was organized from the nature of using responses classified as positive and negative aspects, proposals in with respect to five 5 communication domains: family relationships, social relationships, personal analysis; morphofunctional aspect, and use of writing. To promote and guarantee the autonomy of the respondents, was examiners made use of used assistive technology with the Visual Response Scale.  The responses that total laryngectomy compromises the quality of life in communication amounted to 463 occurrences (65.7%), and that who responses suggesting good quality of life were represented with amounted to 242 occurrences (34.3%), from a total of 705 occurrencesresponses. From Among the five 5 Communication domains, four 4 had percentages of above 63% for occurrences of negative content for impact on communication. Appearance Morphofunctional appearance gave the had the highest percentage of negative content, amounting to 77.3% of cases.  The results showed important limitations of a personal and social nature due to poor communication with their peers. Thus, there is a need for multidisciplinary interventions that aim to minimize the entrapment of negative impact on these people communication

  12. Improved Reliability of Single-Phase PV Inverters by Limiting the Maximum Feed-in Power

    DEFF Research Database (Denmark)

    Yang, Yongheng; Wang, Huai; Blaabjerg, Frede

    2014-01-01

    Grid operation experiences have revealed the necessity to limit the maximum feed-in power from PV inverter systems under a high penetration scenario in order to avoid voltage and frequency instability issues. A Constant Power Generation (CPG) control method has been proposed at the inverter level...... devices, allowing a quantitative prediction of the power device lifetime. A study case on a 3 kW single-phase PV inverter has demonstrated the advantages of the CPG control in terms of improved reliability.......Grid operation experiences have revealed the necessity to limit the maximum feed-in power from PV inverter systems under a high penetration scenario in order to avoid voltage and frequency instability issues. A Constant Power Generation (CPG) control method has been proposed at the inverter level....... The CPG control strategy is activated only when the DC input power from PV panels exceeds a specific power limit. It enables to limit the maximum feed-in power to the electric grids and also to improve the utilization of PV inverters. As a further study, this paper investigates the reliability performance...

  13. Parametric and semiparametric models with applications to reliability, survival analysis, and quality of life

    CERN Document Server

    Nikulin, M; Mesbah, M; Limnios, N

    2004-01-01

    Parametric and semiparametric models are tools with a wide range of applications to reliability, survival analysis, and quality of life. This self-contained volume examines these tools in survey articles written by experts currently working on the development and evaluation of models and methods. While a number of chapters deal with general theory, several explore more specific connections and recent results in "real-world" reliability theory, survival analysis, and related fields.

  14. On-line determination of operating limits incorporating constraint costs and reliability assessment

    International Nuclear Information System (INIS)

    Meisingset, M.; Lovas, G. G.

    1997-01-01

    Problems regarding power system operation following deregulation were discussed. The problems arise as a result of the increased power flow pattern created by deregulation and competitive power markets, resulting in power in excess of N-1, (the capacity of transmission lines available), which in turn creates bottlenecks. In a situation like this, constraint costs and security costs (i.e. the cost of supply interruptions) are incurred as the direct result of the deterministic criteria used in reliability assessment. This paper describes an on-line probabilistic method to determine operating limits based on a trade-off between constraint costs and security costs. The probability of the contingencies depend on the existing weather conditions, which therefore has significant impact on the calculated operating limit. In consequence, the proposed method allows power flow to exceed the N-1 limit during normal weather. Under adverse weather conditions the N-1 criteria should be maintained. 15 refs., 13 figs

  15. A Reliability-Based Determination of Economic Life of Marine power plants

    International Nuclear Information System (INIS)

    Atua, K.

    1999-01-01

    The reliability-based life approach is utilized. Selective failure modes of marine power plants are used for illustration. A case study of the Egyptian Commercial Fleet owned by the Public Sector Company was analyzed and used to establish a demonstration of the expected economic life based on local operating and maintenance conditions. The data acquired is analyzed and failure trend is derived for each failure mode. Probabilistic techniques are used to randomly generate numbers and times of occurrence of different failure modes. The reliability analysis is performed on the life span expected by the manufacture to predict the total number of failures, dependent failures, and cost of failures. Total expenditure due to random failure and cost of scheduled maintenance together with the annual income are utilized (using the time value of money) to determine the economic life of the plant. Conclusions are derived and recommendations for the enhancement of this work in the future are made

  16. Reliability of the Life Satisfaction Questionnaire to assess patients with chronic musculoskeletal pain

    NARCIS (Netherlands)

    Boonstra, Anne M.; Reneman, Michiel F.; Posthumus, Jitze B.; Stewart, Roy E.; Schiphorst Preuper, Henrica R.

    The aim of this study was to determine the reliability of the Life Satisfaction Questionnaire, Dutch version (LSQ-DV), to assess chronic pain patients. The study was designed as test-retest. The setting was the general rehabilitation centre. There were 51 patients over 18 years of age, suffering

  17. Accelerated life testing and reliability of high K multilayer ceramic capacitors

    Science.gov (United States)

    Minford, W. J.

    1981-01-01

    The reliability of one lot of high K multilayer ceramic capacitors was evaluated using accelerated life testing. The degradation in insulation resistance was characterized as a function of voltage and temperature. The times to failure at a voltage-temperature stress conformed to a lognormal distribution with a standard deviation approximately 0.5.

  18. Validity and reliability of the novel thyroid-specific quality of life questionnaire, ThyPRO

    DEFF Research Database (Denmark)

    Watt, Torquil; Hegedus, Laszlo; Grønvold, Mogens

    2010-01-01

    Appropriate scale validity and internal consistency reliability have recently been documented for the new thyroid-specific quality of life (QoL) patient-reported outcome (PRO) measure for benign thyroid disorders, the ThyPRO. However, before clinical use, clinical validity and test...

  19. Reliability testing of the Danish version of the Kidney Disease Quality of Life Short Form

    DEFF Research Database (Denmark)

    Molsted, Stig; Heaf, James; Prescott, Lotte

    2005-01-01

    . MATERIAL AND METHODS: Translation into Danish and back-translation into English were performed. Pilot, field and internal consistency reliability tests were performed. RESULTS: Cronbach's alpha coefficients for the internal reliability test ranged from 0.77 to 0.93 for the eight generic scales. In a test......OBJECTIVE: The questionnaire Kidney Disease Quality of Life Short Form version 1.3 (KDQOL-SF) is valuable for assessing the health-related quality of life in patients treated with chronic dialysis. The aim of this study was to translate and test the reliability of the KDQOL-SF for use in Denmark...... involving all patients, two of the disease-specific scales had Cronbach's alpha coefficients of test of the scores...

  20. Limits to the reliability of size-based fishing status estimation for data-poor stocks

    DEFF Research Database (Denmark)

    Kokkalis, Alexandros; Thygesen, Uffe Høgsbro; Nielsen, Anders

    2015-01-01

    For stocks which are considered “data-poor” no knowledge exist about growth, mortality or recruitment. The only available information is from catches. Here we examine the ability to assess the level of exploitation of a data-poor stock based only on information of the size of individuals in catches....... The model is a formulation of the classic Beverton–Holt theory in terms of size where stock parameters describing growth, natural mortality, recruitment, etc. are determined from life-history invariants. A simulation study was used to compare the reliability of assessments performed under different...... to a considerable improvement in the assessment. Overall, the simulation study demonstrates that it may be possible to classify a data-poor stock as undergoing over- or under-fishing, while the exact status, i.e., how much the fishing mortality is above or below Fmsy, can only be assessed with a substantial...

  1. A Study on the Storage Reliability of LSINS Based on Step-stress Accelerated Life Test

    Directory of Open Access Journals (Sweden)

    Teng Fei

    2015-01-01

    Full Text Available Based on the step-stress accelerated life test and the laser strap-down inertial navigation system, this paper studies the accelerated life model and the test method, provides the likelihood function, the likelihood equation and the two-order derivative when the stress level is k, evaluates the effectiveness of the method with the simulation test model established by MATLAB, applies the research findings in the storage reliability study of the XX laser strap-down inertial navigation system, and puts forward an effective evaluation method of the storage life of the inertial navigation system.

  2. Life Prediction on a T700 Carbon Fiber Reinforced Cylinder with Limited Accelerated Life Testing Data

    Directory of Open Access Journals (Sweden)

    Ma Xiaobing

    2015-01-01

    Full Text Available An accelerated life testing investigation was conducted on a composite cylinder that consists of aluminum alloy and T700 carbon fiber. The ultimate failure stress predictions of cylinders were obtained by the mixing rule and verified by the blasting static pressure method. Based on the stress prediction of cylinder under working conditions, the constant stress accelerated life test of the cylinder was designed. However, the failure data cannot be sufficiently obtained by the accelerated life test due to the time limitation. Therefore, most of the data presented to be high censored in high stress level and zero-failure data in low stress level. When using the traditional method for rupture life prediction, the results showed to be of lower confidence. In this study, the consistency of failure mechanism for carbon fiber and cylinder was analyzed firstly. According to the analysis result, the statistical test information of carbon fiber could be utilized for the accelerated model constitution. Then, rupture life prediction method for cylinder was proposed based on the accelerated life test data and carbon fiber test data. In this way, the life prediction accuracy of cylinder could be improved obviously, and the results showed that the accuracy of this method increased by 35%.

  3. Validity and reliability of the novel thyroid-specific quality of life questionnaire, ThyPRO

    DEFF Research Database (Denmark)

    Watt, Torquil; Hegedüs, Laszlo; Groenvold, Mogens

    2010-01-01

    Background Appropriate scale validity and internal consistency reliability have recently been documented for the new thyroid-specific quality of life (QoL) patient-reported outcome (PRO) measure for benign thyroid disorders, the ThyPRO. However, before clinical use, clinical validity and test......-retest reliability should be evaluated. Aim To investigate clinical ('known-groups') validity and test-retest reliability of the Danish version of the ThyPRO. Methods For each of the 13 ThyPRO scales, we defined groups expected to have high versus low scores ('known-groups'). The clinical validity (known......-groups validity) was evaluated by whether the ThyPRO scales could detect expected differences in a cross-sectional study of 907 thyroid patients. Test-retest reliability was evaluated by intra-class correlations of two responses to the ThyPRO 2 weeks apart in a subsample of 87 stable patients. Results On all 13...

  4. Some infant ventilators do not limit peak inspiratory pressure reliably during active expiration.

    Science.gov (United States)

    Kirpalani, H; Santos-Lyn, R; Roberts, R

    1988-09-01

    In order to minimize barotrauma in newborn infants with respiratory failure, peak inspiratory pressures should not exceed those required for adequate gas exchange. We examined whether four commonly used pressure-limited, constant flow ventilators limit pressure reliably during simulated active expiration against the inspiratory stroke of the ventilator. Three machines of each type were tested at 13 different expiratory flow rates (2 to 14 L/min). Flow-dependent pressure overshoot above a dialed pressure limit of 20 cm H2O was observed in all machines. However, the magnitude differed significantly between ventilators from different manufacturers (p = .0009). Pressure overshoot above 20 cm H2O was consistently lowest in the Healthdyne (0.8 cm H2O at 2 L/min, 3.6 cm H2O at 14 L/min) and highest in the Bourns BP200 (3.0 cm H2O at 2 L/min, 15.4 cm H2O at 14 L/min). We conclude that peak inspiratory pressure overshoots on pressure-limited ventilators occur during asynchronous expiration. This shortcoming may contribute to barotrauma in newborn infants who "fight" positive-pressure ventilation.

  5. LIFELONG LEARNING THROUGH SECOND LIFE: CURRENT TRENDS, POTENTIALS AND LIMITATIONS

    Directory of Open Access Journals (Sweden)

    Nil GOKSEL-CANBEK

    2011-08-01

    Full Text Available Lifelong Learning (LLL has been a remarkable response to people-centered educational demand of 21st century. In order to provide effective formal, non-formal, and informal learning, immersive educational activities undertaken throughout life should be aimed to create a learning society in which people can experience individual and collective learning with no constrains of time or location. The concept of lifelong learning within the context of distance immersive education encompasses diverse 3D activities. The three dimensional, Web-based structured activities supported by distance learning technologies can be viewed as interactive tools which foster LLL. In this perspective, Second Life (SL can be regarded as one of the learning simulation milieus that allow learners to participate in various educational LLL activities in individual or group forms. The following paper examines how SL, taking advantage of its simulative nature and the possibility for creative interaction among participants, which are also common in games, allows the learners to participate in immersive constructivist learning activities. The article will also touch on the current uses of SL as a tool for LLL, as well as its potentials for further development according to the current trends in adult education. Further, the authors will discuss its limitations and will make suggestions towards a more complete pedagogical use.

  6. Remaining life prediction of I and C cables for reliability assessment of NPP systems

    International Nuclear Information System (INIS)

    Santhosh, T.V.; Ghosh, A.K.; Fernandes, B.G.

    2012-01-01

    Highlights: ► A framework for time dependent reliability prediction of I and C cables for use in PSA of NPP has been developed using stress–strength interference theory. ► The proposed methodology has been illustrated with the accelerated thermal aging data on a typical XLPE cable. ► The behavior of insulation resistance when the degradation process is linear or exponential has also been modeled. ► The reliability index or probability of failure obtained from this approach can be used in system reliability evaluation to account for cable aging for PSA of NPP. - Abstract: Instrumentation and control (I and C) cables are one of the most important components in nuclear power plants (NPPs) because they provide power to safety-related equipment and also to transmit signals to and from various controllers to perform safety operations. I and C cables in NPP are subjected to a variety of aging and degradation stressors that can produce immediate degradation or aging-related mechanisms causing the degradation of cable components over time. Although, there exits several life estimation techniques, currently there is no any standard methodology or an approach toward estimating the time dependent reliability of I and C cables that can be directly used in probabilistic safety assessment (PSA) applications. Hence, the objective of this study is to develop an approach to estimate and confirm the continued acceptable margin in cable insulation life over time subjected to aging. This paper presents a framework based on the structural reliability theory to quantify the life time of I and C cable subjecting to thermal aging. Since cross-linked polyethylene (XLPE) cables are extensively being used in Indian NPPs, the remaining life time evaluations have been carried out for a typical XLPE cable. However, the methodology can be extended to other cables such as polyvinyl chloride (PVC), ethylene propylene rubber (EPR), etc.

  7. Rational desires and the limitation of life-sustaining treatment.

    Science.gov (United States)

    Savulescu, Julian

    1994-07-01

    It is accepted that treatment of previously competent, now incompetent patients can be limited if that is what the patient would desire, if she were now competent. Expressed past preferences or an advance directive are often taken to constitute sufficient evidence of what a patient would now desire. I distinguish between desires and rational desires. I argue that for a desire to be an expression of a person's autonomy, it must be or satisfy that person's rational desires. A person rationally desires a course of action if that person desires it while being in possession of all available relevant facts, without committing relevant error of logic, and "vividly imagining" what its consequences would be like for her. I argue that some competent, expressed desires obstruct autonomy. I show that several psychological mechanisms operate to prevent a person rationally evaluating what future life in a disabled state would be like. Rational evaluation is difficult. However, treatment limitation, if it is to respect autonomy, must be in accord with a patient's rational desires, and not merely her expressed desires. I illustrate the implications of these arguments for the use of advance directives and for the treatment of competent patients.

  8. Control of the large renal vein in limited dissected space during laparoscopic nephrectomy: a simple and reliable method

    NARCIS (Netherlands)

    Kijvikai, Kittinut; Laguna, M. Pilar; de la Rosette, Jean

    2006-01-01

    We describe our technique for large renal vein control in the limited dissected space during laparoscopic nephrectomy. This technique is a simple, inexpensive and reliable method, especially for large and short renal vein ligation

  9. Adaptation of Bacillus subtilis to Life at Extreme Potassium Limitation.

    Science.gov (United States)

    Gundlach, Jan; Herzberg, Christina; Hertel, Dietrich; Thürmer, Andrea; Daniel, Rolf; Link, Hannes; Stülke, Jörg

    2017-07-05

    Potassium is the most abundant metal ion in every living cell. This ion is essential due to its requirement for the activity of the ribosome and many enzymes but also because of its role in buffering the negative charge of nucleic acids. As the external concentrations of potassium are usually low, efficient uptake and intracellular enrichment of the ion is necessary. The Gram-positive bacterium Bacillus subtilis possesses three transporters for potassium, KtrAB, KtrCD, and the recently discovered KimA. In the absence of the high-affinity transporters KtrAB and KimA, the bacteria were unable to grow at low potassium concentrations. However, we observed the appearance of suppressor mutants that were able to overcome the potassium limitation. All these suppressor mutations affected amino acid metabolism, particularly arginine biosynthesis. In the mutants, the intracellular levels of ornithine, citrulline, and arginine were strongly increased, suggesting that these amino acids can partially substitute for potassium. This was confirmed by the observation that the supplementation with positively charged amino acids allows growth of B. subtilis even at the extreme potassium limitation that the bacteria experience if no potassium is added to the medium. In addition, a second class of suppressor mutations allowed growth at extreme potassium limitation. These mutations result in increased expression of KtrAB, the potassium transporter with the highest affinity and therefore allow the acquisition and accumulation of the smallest amounts of potassium ions from the environment. IMPORTANCE Potassium is essential for every living cell as it is required for the activity for many enzymes and for maintaining the intracellular pH by buffering the negative charge of the nucleic acids. We have studied the adaptation of the soil bacterium Bacillus subtilis to life at low potassium concentrations. If the major high-affinity transporters are missing, the bacteria are unable to grow

  10. Assessing reliability and useful life of containers for disposal of irradiated fuel waste

    International Nuclear Information System (INIS)

    Doubt, G.

    1984-06-01

    Metal containers for fuel waste isolation are to be designed to last at least 500 years to provide a redundant barrier during the decay period of the high activity components of the waste. To meet the long-life requirement, containers must have a very low failure rate during the design mission, a low incidence of 'juvenile failures' due to undetected defects, and resistance to progressive deterioration from environmental processes. This paper summarizes studies to determine: (1) precedent for low failure rates and relevance to container longevity; (b) the likelihood of initial defects perforating the container before or shortly after emplacement, and estimates of material defect distribution; (c) the utility of reliability analysis techniques for estimating reliability and life of fuel waste containers; (d) other approaches to estimating container longevity and failure versus time distribution

  11. Life Cycle Management for Equipments in Nuclear Plants Based on Reliability

    International Nuclear Information System (INIS)

    Wang Dalin; Sun Jinlong

    2012-01-01

    Life cycle management model based on reliability includes two parts: obtaining failure rate function and founding cost-oriented model to solve. It is actually a single objective programming whose optimal solution is the most economical replacement period. Parameters of failure rate function are estimated by Weibull process fitting with the method of maximum likelihood. The objective function of the model is life-cost function where the dependent variable is replacement period T, with the constraints of failure rate or availability. After foundation of LCM model, we solve it to find the optimal replacement period for the equipments. (author)

  12. Life cycle management for equipments in nuclear plants based on reliability and actual conditions

    International Nuclear Information System (INIS)

    Dalin, Wang; Jingquan, Liu; Peng, Liu

    2010-01-01

    Life cycle management model based on reliability includes two parts: obtaining failure rate function and founding cost-oriented model to solve. It is actually a single objective programming whose optimal solution is the most economical replacement period. Parameters of failure rate function are estimated by Weibull process fitting with the method of maximum likelihood. The objective function of the model is life-cost function where the dependent variable is replacement period T, with the constraints of failure rate or availability. After foundation of LCM model, we solve it to find the optimal replacement period for the equipments. (authors)

  13. Reliability and Validity of the Multidimensional Scale of Life Skills in Late Childhood

    Directory of Open Access Journals (Sweden)

    Minoru Takakura

    2013-04-01

    Full Text Available This study investigated the reliability and validity of the Multidimensional Scale of Life Skills in Late Childhood, an instrument designed to measure a concept similar to “zest for living” in late childhood. A total of 1,888 elementary school students in the 4th, 5th, and 6th grades residing in urban and suburban areas as well as in remote islands of 3 prefectures (Okinawa, Kagoshima, and Nagasaki were surveyed. On the basis of our analysis, 24 items and seven factors were extracted. These factors are problem-solving/synthesis, relationship with friends, personal manners, decision-making and future planning, self-learning, collecting and using information, and leadership. Cronbach’s alpha reliability coefficients were computed for each subscale and ranged from 0.71 to 0.87. Test-retest reliability coefficient values ranged from 0.68 to 0.79. To examine the construct validity of the scales, a goodness-of-fit model was determined by confirmatory factor analysis, and satisfactory values were found (GFI = 0.952, AGFI = 0.937, CFI = 0.966, RMSEA = 0.016. The validity of the goodness-of-fit model and the reliability of the scales indicate that the Multidimensional Scale of Life Skills in Late Childhood is an effective assessment tool.

  14. TURKISH VERSION QUALITY OF LIFE IN ESSENTIAL TREMOR QUESTIONNAIRE (QUEST): VALIDITY AND RELIABILITY STUDY.

    Science.gov (United States)

    Güler, Sibel; Turan, F Nesrin

    2015-09-30

    Our aim was to translate the Quality of Life in Essential Tremor Questionnaire (QUEST) advanced by Troster (2005) and to analyse the validity and reliability of this questionnaire. Two hundred twelve consecutive patients with essential tremor (ET) and forty-three control subjects were included in the study. Permission for the translation and validation of the QUEST scale was obtained. The translation was performed according to the guidelines provided by the publisher. After the translation, the final version of the scale was administered to both groups to determine its reliability and validity. The QUEST Physical, Psychosocial, communication, Hobbies/leisure and Work/finance scores were 0.967, 0.968, 0.933, 0.964 and 0.925, respectively. There were good correlations between each of the QUEST scores that were indicative of good internal consistency. Additionally, we observed that all of the QUEST scores were most strongly related to the right and left arms (p=0.0001). However, we observed that all of the QUEST scores were weakly related to the voice, head and right leg (p=0.0001). These findings support the notion that the Turkish version of the Quality of Life in Essential Tremor (QUEST) questionnaire is a valid and reliable tool for the assessment of the quality of life of patients with ET.

  15. End-of-life content in treatment guidelines for life-limiting diseases.

    Science.gov (United States)

    Mast, Kimberly R; Salama, Marybeth; Silverman, Gabriel K; Arnold, Robert M

    2004-12-01

    Clinical guidelines are systematically developed statements that influence medical practice, education, and funding. Guidelines represent the consensus of leaders, often based on systematic reviews of the literature, regarding the "state of the art." To assess the degree to which end-of-life care is integrated into nationally developed guidelines for chronic, noncurable, life-limiting diseases. Four compendia were reviewed: The Healthcare Standards Directory ECRI, 2001; the Clinical Practice Guidelines Directory, 2000 edition; the National Guidelines Clearinghouse, (guideline.gov); and the National Library of Medicine's MEDLINE database on the OVID platform for guidelines on nine chronic diseases (chronic obstructive pulmonary disease, end-stage liver disease, amyotrophic lateral sclerosis, congestive heart failure, dementia, cerebrovascular accident, end-stage renal disease, cancer [breast, colon, prostate, lung], and human immunodeficiency virus). They were assessed by two reviewers for end-of-life content in 15 domains (e.g., epidemiology of death, symptom management, spiritual, family roles, and settings of care), the presence of eight specific terms dealing with palliative care, integration of palliative care information into the guideline, and descriptive variables. Not available. Each guideline was examined and rated on a 0-2 scale (0, absent content; 1, minimal content; 2, helpful content) using 15 end-of-life content domains. Scores from domains were summed and classified into 3 categories: 4 or less, minimal; 5-12, moderate; and more than 12, significant content. Ten percent of guidelines had significant palliative care content, 64% had minimal content, and 26% had moderate content. The least addressed domains dealt with spirituality, ethics, advocacy and family roles. When guidelines that dealt solely with prevention, acute exacerbations or complications of an illness, or specific treatment modalities were excluded 28% and 16% of these general guidelines

  16. Validity and reliability of the patient assessment of constipation quality of life questionnaire for the Turkish population.

    Science.gov (United States)

    Bengi, Göksel; Yalçın, Mustafa; Akpınar, Hale; Keskinoğlu, Pembe; Ellidokuz, Hülya

    2015-07-01

    There are few specific evaluation forms for evaluating the quality of life among patients with chronic constipation. Our study aimed to determine the validity and reliability of the translated Patient Assessment of Constipation Quality of Life (PAC-QOL) questionnaire for the Turkish population because evidence of its reliability and validity is required to justify its use in other studies and clinical practice. This study included 154 patients with constipation who were treated at the Department of Gastroenterology, Dokuz Eylül University Hospital between January and June 2012. The translated PAC-QOL questionnaire was completed by patients at the clinic and also at a 2-week follow-up to test its reliability. Cronbach's alpha coefficient (internal consistency) was 0.91 (good) for the translated PAC-QOL questionnaire. Time validity was evaluated using the intraclass correlation coefficient (ICC) method, and the ICC value for all questions was confirmed as 0.68 at the 2-week follow-up. The validity of the tool in the study group was evaluated using factor analysis, and the results were highly significant (Kaiser-Meyer-Olkin value: 0.857; Bartlett's test: p=0.001). Questions were categorized according to six factors based on the factor analysis, and these factors explained 65.1% of the total variation. For hypothesis verification of the tool, the correlation coefficient for PAC-QOL and PAC Symptoms (PAC-SYM) was r=0.577 (p<0.001), whereas the correlation coefficient for PAC-QOL and constipation severity score was r=0.457 (p<0.001). The PAC-QOL questionnaire was reliable, although not valid because of the limited sample group.

  17. Reliability and validity of the Malay translated version of diabetes quality of life for youth questionnaire

    Directory of Open Access Journals (Sweden)

    Jamaiyah H

    2013-05-01

    Full Text Available Introduction: Many studies reported poorer quality of life (QoL in youth with diabetes compared to healthy peers. One of the tools used is the Diabetes Quality of Life for Youth (DQoLY questionnaire in English. A validated instrument in Malay is needed to assess the perception of QoL among youth with diabetes in Malaysia. Objective: To translate the modified version, i.e., the DQoLY questionnaire,into Malay and determine its reliability and validity.Methods: Translation and back-translation were used. An expert panel reviewed the translated version for conceptual and content equivalence. The final version was then administered to youths with type 1 diabetes mellitus from the universities and Ministry of Health hospitals between August 2006 and September 2007. Reliability was analysed using Cronbach’s alpha, while validity was confirmed using concurrent validity (HbA1c and self-rated health score.Results: A total of 82 youths with type 1 diabetes (38 males aged 10-18 years were enrolled from eight hospitals. The reliability of overall questionnaire was 0.917, and the reliabilities of the three domains ranged from 0.832 to 0.867. HbA1c was positively correlated with worry (p=0.03. The self-rated health score was found to have significant negative correlation with the “satisfaction” (p=0.013 and “impact” (p=0.007 domains.Conclusion: The Malay translated version of DQoLY questionnaire was reliable and valid to be used among youths with type 2 diabetes in Malaysia.

  18. Reliability and acceptability of the Multiple Sclerosis Quality of Life-29 questionnaire in an English-speaking cohort.

    Science.gov (United States)

    Baker, Georgina; Nair, Krishnan Padmakumari Sivaraman; Baster, Kathleen; Rosato, Rosalba; Solari, Alessandra

    2018-05-01

    Multiple Sclerosis Quality-of-Life Questionnaire-54 (MSQoL-54) is a disease-specific instrument for assessing health-related quality of life (HRQoL). Due to the number of items, the time taken to complete it is long. A shorter 29-item version, Multiple Sclerosis Quality-of-Life Questionnaire-29 (MSQoL-29) is yet to be evaluated in English. To assess reliability and acceptability of English version of MSQoL-29. Among 100 participants with MS who first completed both MSQoL-54 and MSQoL-29, 91 completed MSQoL-29 after 4-8 weeks. We looked for internal consistency (Cronbach's alpha), acceptability, reliability (intraclass correlation coefficients (ICCs)) and agreement (Bland-Altman plots). ICCs were strongly positive between MSQoL-54 and MSQoL-29 (Physical Health Composite (PHC) -ICC = 0.914, confidence interval (CI) = 0.872-0.942; Mental Health Composite (MHC) - ICC = 0.875, CI = 0.814-0.916) and between the two MSQoL-29 (PHC - ICC = 0.970, CI = 0.955-0.980; MHC - ICC = 0.937, CI = 0.904-0.958). On Bland-Altman plots, the MSQoL-29 scores of 95% of participants during two visits were within the limits of agreement (LOAs). Time taken to complete MSQoL-29 was 7.2 ± 2.9 minutes and MSQoL-54 was 19.79 ± 5.4 minutes ( p = 0.0001). MSQoL-29 has good test-retest reliability in English-speaking population and was quicker to complete.

  19. A limited assessment of the ASEP human reliability analysis procedure using simulator examination results

    International Nuclear Information System (INIS)

    Gore, B.R.; Dukelow, J.S. Jr.; Mitts, T.M.; Nicholson, W.L.

    1995-10-01

    This report presents a limited assessment of the conservatism of the Accident Sequence Evaluation Program (ASEP) human reliability analysis (HRA) procedure described in NUREG/CR-4772. In particular, the, ASEP post-accident, post-diagnosis, nominal HRA procedure is assessed within the context of an individual's performance of critical tasks on the simulator portion of requalification examinations administered to nuclear power plant operators. An assessment of the degree to which operator perforn:Lance during simulator examinations is an accurate reflection of operator performance during actual accident conditions was outside the scope of work for this project; therefore, no direct inference can be made from this report about such performance. The data for this study are derived from simulator examination reports from the NRC requalification examination cycle. A total of 4071 critical tasks were identified, of which 45 had been failed. The ASEP procedure was used to estimate human error probability (HEP) values for critical tasks, and the HEP results were compared with the failure rates observed in the examinations. The ASEP procedure was applied by PNL operator license examiners who supplemented the limited information in the examination reports with expert judgment based upon their extensive simulator examination experience. ASEP analyses were performed for a sample of 162 critical tasks selected randomly from the 4071, and the results were used to characterize the entire population. ASEP analyses were also performed for all of the 45 failed critical tasks. Two tests were performed to assess the bias of the ASEP HEPs compared with the data from the requalification examinations. The first compared the average of the ASEP HEP values with the fraction of the population actually failed and it found a statistically significant factor of two bias on the average

  20. The prediction of reliability and residual life of reactor pressure components

    International Nuclear Information System (INIS)

    Nemec, J.; Antalovsky, S.

    1978-01-01

    The paper deals with the problem of PWR pressure components reliability and residual life evaluation and prediction. A physical model of damage cumulation which serves as a theoretical basis for all considerations presents two major aspects. The first one describes the dependence of the degree of damage in the crack leading-edge in pressure components on the reactor system load-time history, i.e. on the number of transient loads. Both stages, fatigue crack initiation and growth through the wall until the critical length is reached, are investigated. The crack is supposed to initiate at the flaws in a strength weld joint or in the bimetallic weld of the base ferritic steel and the austenitic stainless overlay cladding. The growth rates of developed cracks are analysed in respect to different load-time histories. Important cyclic properties of some steels are derived from the low-cycle fatigue theory. The second aspect is the load-time history-dependent process of precipitation, deformation and radiation aging, characterized entirely by the critical crack-length value mentioned above. The fracture point, defined by the equation ''crack-length=critical value'' and hence the residual life, can be evaluated using this model and verified by in-service inspection. The physical model described is randomized by considering all the parameters of the model as random. Monte Carlo methods are applied and fatigue crack initiation and growth is simulated. This permits evaluation of the reliability and residual life of the component. The distributions of material and load-time history parameters are needed for such simulation. Both the deterministic and computer-simulated probabilistic predictions of reliability and residual life are verified by prior-to-failure sequential testing of data coming from in-service NDT periodical inspections. (author)

  1. Reliability and Validity of the Turkish Version of the Voice-Related Quality of Life Measure.

    Science.gov (United States)

    Tezcaner, Zahide Çiler; Aksoy, Songül

    2017-03-01

    This study aims to test the validity and reliability of the Turkish version of the Voice-Related Quality of Life (V-RQOL) questionnaire. This is a nonrandomized, prospective study with control group. The questionnaire was administered to 249 individuals-130 with vocal complaint and 119 without-with a mean age of 37.8 ± 12.3 years. The Turkish version of the Voice Handicap Index (VHI) and perceptual voice evaluation measures were also administered at 2-14 days for retest reliability. The instrument was submitted to validity and reliability evaluation. The V-RQOL measure showed a strong internal consistency and test-retest reliability; the Cronbach's alpha coefficient for the overall V-RQOL was 0.969, the physical functioning domain was 0.949, and the social-emotional domain was 0.940. In the test-retest reliability test, the overall V-RQOL was found to be 0.989. The construct validity of the V-RQOL was determined based on the strength and direction of its relation to the VHI and the perceptual voice evaluation measure. The higher the VHI level, the lower the physical functioning, social-emotional, and overall score levels of the V-RQOL (r = -0.927, r = -0.912, r = -0.944, respectively; P reliability and validity and may play a crucial role in evaluating Turkish-speaking patients with voice disorders. Copyright © 2017 The Voice Foundation. Published by Elsevier Inc. All rights reserved.

  2. Pipeline integrity model-a formative approach towards reliability and life assessment

    International Nuclear Information System (INIS)

    Sayed, A.M.; Jaffery, M.A.

    2005-01-01

    Pipe forms an integral part of transmission medium in oil and gas industry. This holds true for both upstream and downstream segments of this global energy business. With the aging of this asset base, emphasis on its operational aspects has been under immense considerations from the operators and regulators sides. Moreover, the milieu of information area and enhancement in global trade has lifted the barriers on means to forge forward towards better utilization of resources. This has resulted in optimized solutions as priority for business and technical manager's world over. There is a paradigm shift from mere development of 'smart materials' to 'low life cycle cost material'. The force inducing this change is a rationale one: the recovery of development costs is no more a problem in a global community; rather it is the pay-off time which matters most to the materials end users. This means that decision makers are not evaluating just the price offered but are keen to judge the entire life cycle cost of a product. The integrity of pipe are affected by factors such as corrosion, fatigue-crack growth, stress-corrosion cracking, and mechanical damage. Extensive research in the area of reliability and life assessment has been carried out. A number of models concerning with the reliability issues of pipes have been developed and are being used by a number of pipeline operators worldwide. Yet, it is emphasised that there are no substitute for sound engineering judgment and allowance for factors of safety. The ability of a laid down pipe network to transport the intended fluid under pre-defined conditions for the entire project envisaged life, is referred to the reliability of system. The reliability is built into the product through extensive benchmarking against industry standard codes. The process of pipes construction for oil and gas service is regulated through American Petroleum Institute's Specification for Line Pipe. Subsequently, specific programs have been

  3. Harmony in Life Scale - Turkish version: Studies of validity and reliability

    Directory of Open Access Journals (Sweden)

    Seydi Ahmet Satici

    2017-11-01

    Full Text Available Abstract This article presents the adaptation and psychometric evaluation of the Turkish version of Harmony in Life Scale (Turkish-HiL. The present paper investigates (study 1; N 1 = 253 confirmatory factor analysis, measurement invariance; (study 2; N 2 = 231 concurrent validity; (study 3; N 3 = 260 convergent and known-group validities; (study 4; N t − t = 50 test-retest, Cronbach alpha, and composite reliabilities of the Turkish-HiL. In study 1, based on a confirmatory factor analysis, results confirmed that unidimensional-factor structure. The results suggested that the model demonstrated a configural and metric invariance across the gender groups. In study 2, Turkish-HiL significantly correlated with measures of satisfaction with life, subjective happiness, positive affect, and negative affect. In study 3, Turkish-HiL was predicted positively by flourishing, conversely, negatively predicted by depression, anxiety, and stress. Finally, in study 4, alpha, composite and test-retest reliabilities are acceptable. Overall, the scale presented here may prove useful for satisfactorily assessing, in Turkish, the harmony in life of the university students.

  4. Reliability data collection on IC and VLSI devices tested under accelerated life conditions

    International Nuclear Information System (INIS)

    Barry, D.M.; Meniconi, M.

    1986-01-01

    As part of a more general investigation into the reliability and failure causes of semiconductor devices, statistical samples of integrated circuit devices (LM741C) and dynamic random access memory devices (TMS4116) were tested destructively to failure using elevated temperature as the accelerating stress. The devices were operated during the life test and the failure data generated were collected automatically using a multiple question-and-answer program and a process control computer. The failure data were modelled from the lognormal, inverse Gaussian and Weibull distribution using an Arrhenius reaction rate model. The failed devices were later decapsulated for failure cause determination. (orig./DG)

  5. Translation, Validation, and Reliability of the Dutch Late-Life Function and Disability Instrument Computer Adaptive Test.

    Science.gov (United States)

    Arensman, Remco M; Pisters, Martijn F; de Man-van Ginkel, Janneke M; Schuurmans, Marieke J; Jette, Alan M; de Bie, Rob A

    2016-09-01

    Adequate and user-friendly instruments for assessing physical function and disability in older adults are vital for estimating and predicting health care needs in clinical practice. The Late-Life Function and Disability Instrument Computer Adaptive Test (LLFDI-CAT) is a promising instrument for assessing physical function and disability in gerontology research and clinical practice. The aims of this study were: (1) to translate the LLFDI-CAT to the Dutch language and (2) to investigate its validity and reliability in a sample of older adults who spoke Dutch and dwelled in the community. For the assessment of validity of the LLFDI-CAT, a cross-sectional design was used. To assess reliability, measurement of the LLFDI-CAT was repeated in the same sample. The item bank of the LLFDI-CAT was translated with a forward-backward procedure. A sample of 54 older adults completed the LLFDI-CAT, World Health Organization Disability Assessment Schedule 2.0, RAND 36-Item Short-Form Health Survey physical functioning scale (10 items), and 10-Meter Walk Test. The LLFDI-CAT was repeated in 2 to 8 days (mean=4.5 days). Pearson's r and the intraclass correlation coefficient (ICC) (2,1) were calculated to assess validity, group-level reliability, and participant-level reliability. A correlation of .74 for the LLFDI-CAT function scale and the RAND 36-Item Short-Form Health Survey physical functioning scale (10 items) was found. The correlations of the LLFDI-CAT disability scale with the World Health Organization Disability Assessment Schedule 2.0 and the 10-Meter Walk Test were -.57 and -.53, respectively. The ICC (2,1) of the LLFDI-CAT function scale was .84, with a group-level reliability score of .85. The ICC (2,1) of the LLFDI-CAT disability scale was .76, with a group-level reliability score of .81. The high percentage of women in the study and the exclusion of older adults with recent joint replacement or hospitalization limit the generalizability of the results. The Dutch LLFDI

  6. Development of an instrument for direct ozone production rate measurements: measurement reliability and current limitations

    Science.gov (United States)

    Sklaveniti, Sofia; Locoge, Nadine; Stevens, Philip S.; Wood, Ezra; Kundu, Shuvashish; Dusanter, Sébastien

    2018-02-01

    Ground-level ozone (O3) is an important pollutant that affects both global climate change and regional air quality, with the latter linked to detrimental effects on both human health and ecosystems. Ozone is not directly emitted in the atmosphere but is formed from chemical reactions involving volatile organic compounds (VOCs), nitrogen oxides (NOx = NO + NO2) and sunlight. The photochemical nature of ozone makes the implementation of reduction strategies challenging and a good understanding of its formation chemistry is fundamental in order to develop efficient strategies of ozone reduction from mitigation measures of primary VOCs and NOx emissions. An instrument for direct measurements of ozone production rates (OPRs) was developed and deployed in the field as part of the IRRONIC (Indiana Radical, Reactivity and Ozone Production Intercomparison) field campaign. The OPR instrument is based on the principle of the previously published MOPS instrument (Measurement of Ozone Production Sensor) but using a different sampling design made of quartz flow tubes and a different Ox (O3 and NO2) conversion-detection scheme composed of an O3-to-NO2 conversion unit and a cavity attenuated phase shift spectroscopy (CAPS) NO2 monitor. Tests performed in the laboratory and in the field, together with model simulations of the radical chemistry occurring inside the flow tubes, were used to assess (i) the reliability of the measurement principle and (ii) potential biases associated with OPR measurements. This publication reports the first field measurements made using this instrument to illustrate its performance. The results showed that a photo-enhanced loss of ozone inside the sampling flow tubes disturbs the measurements. This issue needs to be solved to be able to perform accurate ambient measurements of ozone production rates with the instrument described in this study. However, an attempt was made to investigate the OPR sensitivity to NOx by adding NO inside the instrument

  7. Dry Blood Spots a Reliable Method for Measurement of Hepatitis B Viral Load in Resource-Limited Settings.

    Directory of Open Access Journals (Sweden)

    Kathrine Stene-Johansen

    Full Text Available Hepatitis B virus (HBV quantification is essential in the management of chronic hepatitis B, both to determine treatment eligibility and in the monitoring of treatment effect. This test, however, is rarely available in resource-limited settings due to high costs and stringent requirements for shipment and storage of plasma. Dried Blood Spots (DBS can be a convenient alternative to plasma, but its use for HBV monitoring has not been investigated under real-life conditions in Africa.The performance of DBS in HBV quantification was investigated using a modified commercial test (Abbott RealTime HBV assay. Paired DBS and plasma samples were collected from an HBV positive cohort in Addis Ababa, Ethiopia. DBS were stored at ambient temperature for 4-39 days before shipment to the laboratory.Twenty-six paired samples were selected covering the total range of quantification, from 2.14 log IU/ml to >7 log IU/ml. HBV was detected in 21 of 21 (100% DBS from patients with a corresponding plasma viral load above 2.70 log IU/ml. The mean difference between plasma and DBS was 0.59 log IU/ml, and the correlation was strong (R2 = 0.92. In stability studies there was no significant change in DBS viral load after storage at room temperature for up to 12 weeks.This study suggests that DBS can be a feasible and reliable alternative to plasma for quantification of HBV in resource-limited settings. DBS can expand access to antiviral treatment for patients in low- and middle-income countries.

  8. Reducing Uncertainty in Fatigue Life Limits of Turbine Engine Alloys

    Science.gov (United States)

    2014-03-01

    10-8 component failures/engine flight hour. This metric underscores the essential role of safety in a design process that simultaneously strives to...This metric underscores the essential role of safety in a design process that simultaneously strives to achieve perfor- mance, efficiency, reliability...resonance at 20 kHz. At the highest stres - ses, surface-connected a particles typically served as the primary sites for crack initiation (e.g., Fig. 4

  9. Life Cycle Assessment for desalination: a review on methodology feasibility and reliability.

    Science.gov (United States)

    Zhou, Jin; Chang, Victor W-C; Fane, Anthony G

    2014-09-15

    As concerns of natural resource depletion and environmental degradation caused by desalination increase, research studies of the environmental sustainability of desalination are growing in importance. Life Cycle Assessment (LCA) is an ISO standardized method and is widely applied to evaluate the environmental performance of desalination. This study reviews more than 30 desalination LCA studies since 2000s and identifies two major issues in need of improvement. The first is feasibility, covering three elements that support the implementation of the LCA to desalination, including accounting methods, supporting databases, and life cycle impact assessment approaches. The second is reliability, addressing three essential aspects that drive uncertainty in results, including the incompleteness of the system boundary, the unrepresentativeness of the database, and the omission of uncertainty analysis. This work can serve as a preliminary LCA reference for desalination specialists, but will also strengthen LCA as an effective method to evaluate the environment footprint of desalination alternatives. Copyright © 2014 Elsevier Ltd. All rights reserved.

  10. A reliability based stress-life evaluation of aluminium-graphite particulate composites

    International Nuclear Information System (INIS)

    Achutha, M.V.; Sridhara, B.K.; Abdul Budan, D.

    2008-01-01

    Fatigue tests were conducted on sand cast aluminium-graphite composite specimens on Rotating Beam Fatigue Testing Machine with three different stress levels. Aluminium-graphite (LM 25-5% graphite) composite was processed by closed mould sand casting method. Three-stress level fatigue test program was planned for carrying out fatigue experiments. Three different stress levels selected for fatigue experiments were a fraction of ultimate tensile strength. Statistical design of fatigue experiments was carried out to determine the sample size at each stress level. Experimental results are presented in the form of stress-life (S-N) curves and reliability-stress-life (R-S-N) curves, which are helpful for designers. The S-N curve of the aluminium-graphite composite was compared with its matrix alloy LM 25. Comparison revealed that the fatigue behaviour of the aluminium-graphite composite is superior to that of the matrix alloy

  11. The Effect of Epoxy Molding Compound Floor Life to Reliability Performance and mold ability for QFN Package

    Science.gov (United States)

    Peanpunga, Udom; Ugsornrat, Kessararat; Thorlor, Panakamol; Sumithpibul, Chalermsak

    2017-09-01

    This research studied about an epoxy molding compound (EMC) floor life to reliability performance of integrated circuit (IC) package. Molding is the process for protecting the die of IC package form mechanical and chemical reaction from external environment by shaping EMC. From normal manufacturing process, the EMC is stored in the frozen at 5oC and left at around room temperature for aging time or floor life before molding process. The EMC floor life effect to its properties and reliability performance of IC package. Therefore, this work interested in varied the floor life of EMC before molding process to analyze properties of EMC such as spiral flow length, gelation time, and viscosity. In experiment, the floor life of EMC was varied to check the effect of its property to reliability performance. The EMC floor life were varied from 0 hours to 60 hours with a step of 12 hours and observed wire sweep, incomplete EMC, and delamination inside the packages for 3x3, 5x5 and 8x8 mm2 of QFN packages. The evaluation showed about clearly effect of EMC floor life to IC packaging reliability. EMC floor life is not any concern for EMC property, moldabilty, and reliability from 0 hours to 48 hours for molding process of 3x3,5x5 and 8x8 mm2 QFN packaging manufacturing

  12. Development of the Knee Quality of Life (KQoL-26 26-item questionnaire: data quality, reliability, validity and responsiveness

    Directory of Open Access Journals (Sweden)

    Atwell Chris

    2008-07-01

    Full Text Available Abstract Background This article describes the development and validation of a self-reported questionnaire, the KQoL-26, that is based on the views of patients with a suspected ligamentous or meniscal injury of the knee that assesses the impact of their knee problem on the quality of their lives. Methods Patient interviews and focus groups were used to derive questionnaire content. The instrument was assessed for data quality, reliability, validity, and responsiveness using data from a randomised trial and patient survey about general practitioners' use of Magnetic Resonance Imaging for patients with a suspected ligamentous or meniscal injury. Results Interview and focus group data produced a 40-item questionnaire designed for self-completion. 559 trial patients and 323 survey patients responded to the questionnaire. Following principal components analysis and Rasch analysis, 26 items were found to contribute to three scales of knee-related quality of life: physical functioning, activity limitations, and emotional functioning. Item-total correlations ranged from 0.60–0.82. Cronbach's alpha and test retest reliability estimates were 0.91–0.94 and 0.80–0.93 respectively. Hypothesised correlations with the Lysholm Knee Scale, EQ-5D, SF-36 and knee symptom questions were evidence for construct validity. The instrument produced highly significant change scores for 65 trial patients indicating that their knee was a little or somewhat better at six months. The new instrument had higher effect sizes (range 0.86–1.13 and responsiveness statistics (range 1.50–2.13 than the EQ-5D and SF-36. Conclusion The KQoL-26 has good evidence for internal reliability, test-retest reliability, validity and responsiveness, and is recommended for use in randomised trials and other evaluative studies of patients with a suspected ligamentous or meniscal injury.

  13. Development of the knee quality of life (KQoL-26) 26-item questionnaire: data quality, reliability, validity and responsiveness.

    Science.gov (United States)

    Garratt, Andrew M; Brealey, Stephen; Robling, Michael; Atwell, Chris; Russell, Ian; Gillespie, William; King, David

    2008-07-10

    This article describes the development and validation of a self-reported questionnaire, the KQoL-26, that is based on the views of patients with a suspected ligamentous or meniscal injury of the knee that assesses the impact of their knee problem on the quality of their lives. Patient interviews and focus groups were used to derive questionnaire content. The instrument was assessed for data quality, reliability, validity, and responsiveness using data from a randomised trial and patient survey about general practitioners' use of Magnetic Resonance Imaging for patients with a suspected ligamentous or meniscal injury. Interview and focus group data produced a 40-item questionnaire designed for self-completion. 559 trial patients and 323 survey patients responded to the questionnaire. Following principal components analysis and Rasch analysis, 26 items were found to contribute to three scales of knee-related quality of life: physical functioning, activity limitations, and emotional functioning. Item-total correlations ranged from 0.60-0.82. Cronbach's alpha and test retest reliability estimates were 0.91-0.94 and 0.80-0.93 respectively. Hypothesised correlations with the Lysholm Knee Scale, EQ-5D, SF-36 and knee symptom questions were evidence for construct validity. The instrument produced highly significant change scores for 65 trial patients indicating that their knee was a little or somewhat better at six months. The new instrument had higher effect sizes (range 0.86-1.13) and responsiveness statistics (range 1.50-2.13) than the EQ-5D and SF-36. The KQoL-26 has good evidence for internal reliability, test-retest reliability, validity and responsiveness, and is recommended for use in randomised trials and other evaluative studies of patients with a suspected ligamentous or meniscal injury.

  14. Reproducibility and Reliability of the Quality of Life Questionnaire in Patients With Atrial Fibrillation

    Directory of Open Access Journals (Sweden)

    Rita Simone Lopes Moreira

    2016-03-01

    Full Text Available Abstract Background: Studies have shown the impact of atrial fibrillation (AF on the patients' quality of life. Specific questionnaires enable the evaluation of relevant events. We previously developed a questionnaire to assess the quality of life of patients with AF (AFQLQ version 1, which was reviewed in this study, and new domains were added. Objective: To demonstrate the reproducibility of the AFQLQ version 2 (AFQLQ v.2, which included the domains of fatigue, illness perception and well-being. Methods: We applied 160 questionnaires (AFQLQ v.2 and SF-36 to 40 patients, at baseline and 15 days after, to measure inter- and intraobserver reproducibility. The analysis of quality of life stability was determined by test-retest, applying the Bartko intraclass correlation coefficient (ICC. Internal consistency was assessed by Cronbach's alpha test. Results: The total score of the test-retest (n = 40 had an ICC of 0.98 in the AFQLQ v.2, and of 0.94 in the SF36. In assessing the intra- and interobserver reproducibility of the AFQLQ v.2, the ICC reliability was 0.98 and 0.97, respectively. The internal consistency had a Cronbach's alpha coefficient of 0.82, compatible with good agreement of the AFQLQ v.2. Conclusion: The AFQLQ v.2 performed better than its previous version. Similarly, the domains added contributed to make it more comprehensive and robust to assess the quality of life of patients with AF.

  15. Reliabilities of mental rotation tasks: limits to the assessment of individual differences.

    Science.gov (United States)

    Hirschfeld, Gerrit; Thielsch, Meinald T; Zernikow, Boris

    2013-01-01

    Mental rotation tasks with objects and body parts as targets are widely used in cognitive neuropsychology. Even though these tasks are well established to study between-groups differences, the reliability on an individual level is largely unknown. We present a systematic study on the internal consistency and test-retest reliability of individual differences in mental rotation tasks comparing different target types and orders of presentations. In total n = 99 participants (n = 63 for the retest) completed the mental rotation tasks with hands, feet, faces, and cars as targets. Different target types were presented in either randomly mixed blocks or blocks of homogeneous targets. Across all target types, the consistency (split-half reliability) and stability (test-retest reliabilities) were good or acceptable both for intercepts and slopes. At the level of individual targets, only intercepts showed acceptable reliabilities. Blocked presentations resulted in significantly faster and numerically more consistent and stable responses. Mental rotation tasks-especially in blocked variants-can be used to reliably assess individual differences in global processing speed. However, the assessment of the theoretically important slope parameter for individual targets requires further adaptations to mental rotation tests.

  16. End-stage dementia spark of life: reliability and validity of the "GATOS" questionnaire.

    Science.gov (United States)

    Tsoucalas, Gregory; Bourelia, Stamati; Kalogirou, Vaso; Giatsiou, Styliani; Mavrogiannaki, Eirini; Gatos, Georgios; Galanos, Antonis; Repana, Olga; Iliadou, Eleni; Antoniou, Antonis; Sgantzos, Markos; Gatos, Konstantinos

    2015-01-01

    Fl oor effects are present in most dementia assessment tools as dementia progresses and the in-depth assessment of patients considered more or less on vegetative state is questionable. To develop a questionnaire (the "Gatos Clinical Test-GCT") for the assessment of end-stage demented patients. Five hundred patients with dementia of various causes and an MMSE score between 0 and 2 were enrolled in the study. The GCT consists of 14 closed type questions rated on a Likert scale. The total score is used to evaluate patient's dementia. Various aspects of validity and reliability (including face, content and structural validity as well as test-retest reliability) were examined. Three subscales "Autonomy/Alertness", "Gnosias" and "Somatokinetic function" were defined, with a Cronbach equal to 0.851, 0.756 and 0.598 respectively. The GCT subscales and total score were statistically significant higher in patients with MMSE score 1 or 2 compared with those with MMSE score 0 (pGATOS" questionnaire is a valid and reliable test for patients with severe dementia, aiming at identification of those patients who could sustain some quality of life. It is a relatively short and easy to administer tool. As dementia prevalence is expected to rise further worldwide we believe that GCT could offer valuable services to health professionals, caregivers and patients.

  17. Accuracy and Reliability in the Prediction of End-of-Life Performance of Solar Generators

    Science.gov (United States)

    Rapp, Etienne

    2008-09-01

    The end-of-life power analysis of solar arrays is calculated using a combination of arithmetic and root square sums of loss factors. These loss factors are sometimes linked to degradations, sometimes linked to uncertainties. The uncertainties of the degradations are taken into account considering contractual "worst cases". This paper will put the first stones for a move "metrological" evaluation of the probable performance associated with a standard uncertainty. The turn from silicon to triple junction solar cells induces some changes in the degradation parameters of solar arrays: * The triple junction cells are more sensitive to UV darkening than silicon ones. * The cell voltage is higher and the current is lower. Then the cell strings are shorter, and there are more strings in parallel. This induces some changes in the reliability analyses and risk management. * The failure modes and failure rates of these cells have to be compared and discussed. We try to define improved rules to design solar arrays for end of life performance, for a better knowledge of the margins and a better reliability.

  18. Measuring Mobility Limitations in Children with Cerebral Palsy: Interrater and Intrarater Reliability of a Mobility Questionnaire (MobQues)

    Science.gov (United States)

    Van Ravesteyn, Nicolien T.; Dallmeijer, Annet J.; Scholtes, Vanessa A.; Roorda, Leo D.; Becher, Jules G.

    2010-01-01

    Aim: The objective of this study was to assess the reliability of a mobility questionnaire (MobQues) that was developed to measure the mobility limitations of children with cerebral palsy (CP) as rated by their parents. A clinical version of the questionnaire, consisting of 47 items (MobQues47), is available, as well as a research version with 28…

  19. Hierarchical complexity and the size limits of life.

    Science.gov (United States)

    Heim, Noel A; Payne, Jonathan L; Finnegan, Seth; Knope, Matthew L; Kowalewski, Michał; Lyons, S Kathleen; McShea, Daniel W; Novack-Gottshall, Philip M; Smith, Felisa A; Wang, Steve C

    2017-06-28

    Over the past 3.8 billion years, the maximum size of life has increased by approximately 18 orders of magnitude. Much of this increase is associated with two major evolutionary innovations: the evolution of eukaryotes from prokaryotic cells approximately 1.9 billion years ago (Ga), and multicellular life diversifying from unicellular ancestors approximately 0.6 Ga. However, the quantitative relationship between organismal size and structural complexity remains poorly documented. We assessed this relationship using a comprehensive dataset that includes organismal size and level of biological complexity for 11 172 extant genera. We find that the distributions of sizes within complexity levels are unimodal, whereas the aggregate distribution is multimodal. Moreover, both the mean size and the range of size occupied increases with each additional level of complexity. Increases in size range are non-symmetric: the maximum organismal size increases more than the minimum. The majority of the observed increase in organismal size over the history of life on the Earth is accounted for by two discrete jumps in complexity rather than evolutionary trends within levels of complexity. Our results provide quantitative support for an evolutionary expansion away from a minimal size constraint and suggest a fundamental rescaling of the constraints on minimal and maximal size as biological complexity increases. © 2017 The Author(s).

  20. Reliability-based fatigue life estimation of shear riveted connections considering dependency of rivet hole failures

    Directory of Open Access Journals (Sweden)

    Leonetti* Davide

    2018-01-01

    Full Text Available Standards and guidelines for the fatigue design of riveted connections make use of a stress range-endurance (S-N curve based on the net section stress range regardless of the number and the position of the rivets. Almost all tests on which S-N curves are based, are performed with a minimum number of rivets. However, the number of rivets in a row is expected to increase the fail-safe behaviour of the connection, whereas the number of rows is supposed to decrease the theoretical stress concentration at the critical locations, and hence these aspects are not considered in the S-N curves. This paper presents a numerical model predicting the fatigue life of riveted connections by performing a system reliability analysis on a double cover plated riveted butt joint. The connection is considered in three geometries, with different number of rivets in a row and different number of rows. The stress state in the connection is evaluated using a finite element model in which the friction coefficient and the clamping force in the rivets are considered in a deterministic manner. The probability of failure is evaluated for the main plate, and fatigue failure is assumed to be originating at the sides of the rivet holes, the critical locations, or hot-spots. The notch stress approach is applied to assess the fatigue life, considered to be a stochastic quantity. Unlike other system reliability models available in the literature, the evaluation of the probability of failure takes into account the stochastic dependence between the failures at each critical location modelled as a parallel system, which means considering the change of the state of stress in the connection when a ligament between two rivets fails. A sensitivity study is performed to evaluate the effect of the pretension in the rivet and the friction coefficient on the fatigue life.

  1. The List of Threatening Experiences: the reliability and validity of a brief life events questionnaire.

    Science.gov (United States)

    Brugha, T S; Cragg, D

    1990-07-01

    During the 23 years since the original work of Holmes & Rahe, research into stressful life events on human subjects has tended towards the development of longer and more complex inventories. The List of Threatening Experiences (LTE) of Brugha et al., by virtue of its brevity, overcomes difficulties of clinical application. In a study of 50 psychiatric patients and informants, the questionnaire version of the list (LTE-Q) was shown to have high test-retest reliability, and good agreement with informant information. Concurrent validity, based on the criterion of independently rated adversity derived from a semistructured life events interview, making use of the Life Events and Difficulties Scales (LEDS) method developed by Brown & Harris, showed both high specificity and sensitivity. The LTE-Q is particularly recommended for use in psychiatric, psychological and social studies in which other intervening variables such as social support, coping, and cognitive variables are of interest, and resources do not allow for the use of extensive interview measures of stress.

  2. [Intra-rater Reliability for the Questionnaire on Activity Limitations and Participation Restrictions of Children With ADHD].

    Science.gov (United States)

    Salamanca Duque, Luisa Matilde; Naranjo Aristizábal, María Mercedes; Gutiérrez Ríos, Gladys Helena; Prieto, Jaime Bayona

    2014-03-01

    Questionnaires for evaluating activity limitations and participation restrictions in children with ADHD (CLARP-TDAH) has recently been developed in Colombia, based on the suggestions made by the WHO from the International Classification of Functioning, Disability and Health (ICF), allowing clinical evaluation beyond an evaluation of the functionality and functioning of children in their family and school environments. Previous research with the questionnaire proved useful in the multidisciplinary approach of Colombian children with ADHD. This study determines the level of intra-rater reliability for questionnaires CLARP-TDAH Parents and Teachers. The study included a non-random sample of 203 Colombian children attending school and diagnosed with ADHD. Intra-rater reliability and the reproducibility of the results was determined using the Kappa index. The informants were parents and teachers. Kappa values >0.7 were obtained for the intra-rater reliability of the questionnaire domains of CLARP-TDAH Parents, while for CLARP-TDAH Teachers domains these values were >0.8. CLARP-TDAH questionnaires are a tool with a good level of intra-rater reliability, which allows a reliable assessment of activity limitations and participation restrictions in order to determine the level of functioning at home and school. Copyright © 2014 Asociación Colombiana de Psiquiatría. Publicado por Elsevier España. All rights reserved.

  3. Quality of Life among Persons with HIV/AIDS in Iran: Internal Reliability and Validity of an International Instrument and Associated Factors

    Directory of Open Access Journals (Sweden)

    Pedram Razavi

    2012-01-01

    Full Text Available The purpose of this cross-sectional study on 191 HIV/AIDS patient was to prepare the first Persian translation of complete WHOQOL-HIV instrument, evaluate its reliability and validity, and apply it to determine quality of life and its associated factors in Tehran, Iran. Student's t-test was used to compare quality of life between groups. Mean Cronbach’s α of facets in all six domains of instrument were more than 0.6 indicating good reliability. Item/total corrected correlations coefficients had a lower limit of more than 0.5 in all facets except for association between energy and fatigue facet and physical domain. Compared to younger participants, patients older than 35 years had significantly lower scores in overall quality of life (P = 0.003, social relationships (P = 0.021, and spirituality/religion/personal beliefs (P = 0.024. Unemployed patients had significantly lower scores in overall quality of life (P = 0.01, level of independence (P = 0.004, and environment (P = 0.001 compared to employed participants. This study demonstrated that the standard, complete WHOQOL-HIV 120 instrument translated into Farsi and evaluated among Iranian participants provides a reliable and valid basis for future research on quality of life for HIV and other patients in Iran.

  4. Reliability and validity of the body image quality of life inventory: version for Brazilian burn victims.

    Science.gov (United States)

    Assunção, Flávia Fernanda Oliveira; Dantas, Rosana Aparecida Spadoti; Ciol, Márcia Aparecida; Gonçalves, Natália; Farina, Jayme Adriano; Rossi, Lidia Aparecida

    2013-06-01

    The aims of this study were to adapt the Body Image Quality of Life Inventory (BIQLI) into Brazilian Portuguese (BP) and to assess the psychometric properties of the adapted version. Construct validity was assessed by correlating the BIQLI-BP scores with the Rosenberg's Self-Esteem Scale, with Burns Specific Health Scale-Revised (BSHS-R), and with gender, total body surface area burned, and visibility of the scars. Participants were 77 adult burn patients. Cronbach's alpha for the adapted version was .90 and moderate linear correlations were found between body image and self-esteem and between BIQLI-BP scores and two domains of the BSHS-R: affect and body image and interpersonal relationships. The BIQLI-BP showed acceptable levels of reliability and validity for Brazilian burn patients. Copyright © 2013 Wiley Periodicals, Inc.

  5. Reproducibility and reliability of hypoglycaemic episodes recorded with Continuous Glucose Monitoring System (CGMS) in daily life

    DEFF Research Database (Denmark)

    Høi-Hansen, T; Pedersen-Bjergaard, U; Thorsteinsson, B

    2005-01-01

    AIM: Continuous glucose monitoring may reveal episodes of unrecognized hypoglycaemia. We evaluated reproducibility and reliability of hypoglycaemic episodes recorded in daily life by the Medtronic MiniMed Continuous Glucose Monitoring System (CGMS). METHODS: Twenty-nine adult patients with Type 1...... data were recalibrated generating four different CGMS data sets [left-A (left side of abdomen, calibration set A), left-B, right-A and right-B]. Agreement between CGMS data sets was evaluated during hypoglycaemic events, comparing CGMS readings = 2.2 mmol/l with nadir values from corresponding CGMS...... data sets. CGMS readings were also compared with independent self-monitored blood glucose (SMBG) values. RESULTS: With hypoglycaemia (CGMS readings = 2.2 mmol/l) in calibration set left-A, values below 3.5 mmol/l were present in 99% (95% CI: 95-100%) of samples in left-B, 91% (95% CI: 84...

  6. The Behçet's Disease Quality of Life: Reliability and Validity of the Korean Version

    Science.gov (United States)

    Yi, Sang Won; Kim, Ji-Hae; Lim, Ki-Young; Bang, Dongsik; Lee, Sungnack

    2008-01-01

    Purpose The Behçet's Disease Quality of Life (BD-QoL) is a BD-specific measure developed in the UK. The aim of this study was to adapt the BD-QoL for use in Korea. Patients and Methods The translation was based on the guidelines for cross-cultural adaptation. A total of 201 Korean patients with BD participated in this study. To evaluate the psychometric properties, internal consistency and test-retest reliability were used. Factor analysis was performed to examine the construct validity. To provide further evidence for validity, the correlation of BD-QoL with the Clinical Activity Form for Korean Patients with BD (BDCAF-K) and the Center for Epidemiologic Studies-Depression (CES-D) scales was assessed. Results The Korean version had high internal consistency (Cronbach's alpha, 0.93) and test-retest reliability (r = 0.835). Factor analysis of the questionnaire revealed one interpretable factor as a general health-related quality of life factor. The Korean version significantly correlated with scores of CES-D (r = 0.749, p= 0.000), self-rating scale of well-being over the past 28 days (r = 0.446, p= 0.000), and BDCAF-K score (r = 0.502, p = 0.000). Conclusion Adaptation of the BD-QoL for use in Korea was successful. Together with the BDCAF-K, it may be a valuable tool for assessing the influence of interventions in BD patients and outcome in clinical trials. PMID:18972588

  7. The Reliability of Turkish "Basic Life Support" and "Cardiac Massage" Videos Uploaded to Websites.

    Science.gov (United States)

    Elicabuk, Hayri; Yaylacı, Serpil; Yilmaz, Atakan; Hatipoglu, Celile; Kaya, F Gokhan; Serinken, Mustafa

    2016-02-01

    In this study, the reliability of Turkish cardiac massage and Basic Life Support (BLS) videos, which have already been downloaded from three website such as YouTube, Google, Yahoo following the publication of 2010 cardiopulmonary resuscitation (CPR) guideline and their suitability to the same guideline were researched. The videos uploaded to the three web-site to search videos on internet were queried by using the keywords "cardiac massage" and "basic life support". Videos that had been uploaded between January 2011 and July 2014 were analyzed and scored by two experienced emergency specialists. A total of 1126 videos were obtained. 1029 of the videos (91.4%) were excluded by researchers. 97 videos were detected to accord with study criteria. Despite most of the videos were found on Google website by keywords, the enormous part of videos proper to criteria were sourced from YouTube website (n=65, 67.0%). One fourth of the videos (24.7%) were observed to not be suitable for 2010 CPR guideline. AED usage was mentioned slightly in the videos (14.4%). Median score of the videos is 5 (IQR: 4-6). The rate and scores of the videos uploaded by official institution or association were significantly higher than others (p=0.007 and 0.006, respectively). Moreover, scores of the videos compatible with guidelines uploaded by official institution or association and medical personal were also found higher (p=0.001). Eventually, all the data obtained in this study support that Turkish videos were not reliable on the subject of BLS and cardiac massage. It is promising that videos with high follow-up rates also have been scored higher.

  8. Bayesian Reliability Estimation for Deteriorating Systems with Limited Samples Using the Maximum Entropy Approach

    OpenAIRE

    Xiao, Ning-Cong; Li, Yan-Feng; Wang, Zhonglai; Peng, Weiwen; Huang, Hong-Zhong

    2013-01-01

    In this paper the combinations of maximum entropy method and Bayesian inference for reliability assessment of deteriorating system is proposed. Due to various uncertainties, less data and incomplete information, system parameters usually cannot be determined precisely. These uncertainty parameters can be modeled by fuzzy sets theory and the Bayesian inference which have been proved to be useful for deteriorating systems under small sample sizes. The maximum entropy approach can be used to cal...

  9. Life Prediction/Reliability Data of Glass-Ceramic Material Determined for Radome Applications

    Science.gov (United States)

    Choi, Sung R.; Gyekenyesi, John P.

    2002-01-01

    Brittle materials, ceramics, are candidate materials for a variety of structural applications for a wide range of temperatures. However, the process of slow crack growth, occurring in any loading configuration, limits the service life of structural components. Therefore, it is important to accurately determine the slow crack growth parameters required for component life prediction using an appropriate test methodology. This test methodology also should be useful in determining the influence of component processing and composition variables on the slow crack growth behavior of newly developed or existing materials, thereby allowing the component processing and composition to be tailored and optimized to specific needs. Through the American Society for Testing and Materials (ASTM), the authors recently developed two test methods to determine the life prediction parameters of ceramics. The two test standards, ASTM 1368 for room temperature and ASTM C 1465 for elevated temperatures, were published in the 2001 Annual Book of ASTM Standards, Vol. 15.01. Briefly, the test method employs constant stress-rate (or dynamic fatigue) testing to determine flexural strengths as a function of the applied stress rate. The merit of this test method lies in its simplicity: strengths are measured in a routine manner in flexure at four or more applied stress rates with an appropriate number of test specimens at each applied stress rate. The slow crack growth parameters necessary for life prediction are then determined from a simple relationship between the strength and the applied stress rate. Extensive life prediction testing was conducted at the NASA Glenn Research Center using the developed ASTM C 1368 test method to determine the life prediction parameters of a glass-ceramic material that the Navy will use for radome applications.

  10. reliability reliability

    African Journals Online (AJOL)

    eobe

    Corresponding author, Tel: +234-703. RELIABILITY .... V , , given by the code of practice. However, checks must .... an optimization procedure over the failure domain F corresponding .... of Concrete Members based on Utility Theory,. Technical ...

  11. Life Prediction on a T700 Carbon Fiber Reinforced Cylinder with Limited Accelerated Life Testing Data

    OpenAIRE

    Ma Xiaobing; Zhang Yongbo

    2015-01-01

    An accelerated life testing investigation was conducted on a composite cylinder that consists of aluminum alloy and T700 carbon fiber. The ultimate failure stress predictions of cylinders were obtained by the mixing rule and verified by the blasting static pressure method. Based on the stress prediction of cylinder under working conditions, the constant stress accelerated life test of the cylinder was designed. However, the failure data cannot be sufficiently obtained by the accelerated life ...

  12. The life and times of the central limit theorem

    CERN Document Server

    Adams, William J

    2009-01-01

    About the First Edition: The study of any topic becomes more meaningful if one also studies the historical development that resulted in the final theorem. …This is an excellent book on mathematics in the making. -Philip Peak, The Mathematics Teacher, May, 1975 I find the book very interesting. It contains valuable information and useful references. It can be recommended not only to historians of science and mathematics but also to students of probability and statistics. -Wei-Ching Chang, Historica Mathematica, August, 1976 In the months since I wrote…I have read it from cover to cover at least once and perused it here and there a number of times. I still find it a very interesting and worthwhile contribution to the history of probability and statistics. -Churchill Eisenhart, past president of the American Statistical Association, in a letter to the author, February 3, 1975 The name Central Limit Theorem covers a wide variety of results involving the determination of necessary and sufficient conditions und...

  13. Bayesian Reliability Estimation for Deteriorating Systems with Limited Samples Using the Maximum Entropy Approach

    Directory of Open Access Journals (Sweden)

    Ning-Cong Xiao

    2013-12-01

    Full Text Available In this paper the combinations of maximum entropy method and Bayesian inference for reliability assessment of deteriorating system is proposed. Due to various uncertainties, less data and incomplete information, system parameters usually cannot be determined precisely. These uncertainty parameters can be modeled by fuzzy sets theory and the Bayesian inference which have been proved to be useful for deteriorating systems under small sample sizes. The maximum entropy approach can be used to calculate the maximum entropy density function of uncertainty parameters more accurately for it does not need any additional information and assumptions. Finally, two optimization models are presented which can be used to determine the lower and upper bounds of systems probability of failure under vague environment conditions. Two numerical examples are investigated to demonstrate the proposed method.

  14. Diagnosing developmental dyscalculia on the basis of reliable single case FMRI methods: promises and limitations.

    Directory of Open Access Journals (Sweden)

    Philipp Johannes Dinkel

    Full Text Available FMRI-studies are mostly based on a group study approach, either analyzing one group or comparing multiple groups, or on approaches that correlate brain activation with clinically relevant criteria or behavioral measures. In this study we investigate the potential of fMRI-techniques focusing on individual differences in brain activation within a test-retest reliability context. We employ a single-case analysis approach, which contrasts dyscalculic children with a control group of typically developing children. In a second step, a support-vector machine analysis and cluster analysis techniques served to investigate similarities in multivariate brain activation patterns. Children were confronted with a non-symbolic number comparison and a non-symbolic exact calculation task during fMRI acquisition. Conventional second level group comparison analysis only showed small differences around the angular gyrus bilaterally and the left parieto-occipital sulcus. Analyses based on single-case statistical procedures revealed that developmental dyscalculia is characterized by individual differences predominantly in visual processing areas. Dyscalculic children seemed to compensate for relative under-activation in the primary visual cortex through an upregulation in higher visual areas. However, overlap in deviant activation was low for the dyscalculic children, indicating that developmental dyscalculia is a disorder characterized by heterogeneous brain activation differences. Using support vector machine analysis and cluster analysis, we tried to group dyscalculic and typically developing children according to brain activation. Fronto-parietal systems seem to qualify for a distinction between the two groups. However, this was only effective when reliable brain activations of both tasks were employed simultaneously. Results suggest that deficits in number representation in the visual-parietal cortex get compensated for through finger related aspects of number

  15. Diagnosing developmental dyscalculia on the basis of reliable single case FMRI methods: promises and limitations.

    Science.gov (United States)

    Dinkel, Philipp Johannes; Willmes, Klaus; Krinzinger, Helga; Konrad, Kerstin; Koten, Jan Willem

    2013-01-01

    FMRI-studies are mostly based on a group study approach, either analyzing one group or comparing multiple groups, or on approaches that correlate brain activation with clinically relevant criteria or behavioral measures. In this study we investigate the potential of fMRI-techniques focusing on individual differences in brain activation within a test-retest reliability context. We employ a single-case analysis approach, which contrasts dyscalculic children with a control group of typically developing children. In a second step, a support-vector machine analysis and cluster analysis techniques served to investigate similarities in multivariate brain activation patterns. Children were confronted with a non-symbolic number comparison and a non-symbolic exact calculation task during fMRI acquisition. Conventional second level group comparison analysis only showed small differences around the angular gyrus bilaterally and the left parieto-occipital sulcus. Analyses based on single-case statistical procedures revealed that developmental dyscalculia is characterized by individual differences predominantly in visual processing areas. Dyscalculic children seemed to compensate for relative under-activation in the primary visual cortex through an upregulation in higher visual areas. However, overlap in deviant activation was low for the dyscalculic children, indicating that developmental dyscalculia is a disorder characterized by heterogeneous brain activation differences. Using support vector machine analysis and cluster analysis, we tried to group dyscalculic and typically developing children according to brain activation. Fronto-parietal systems seem to qualify for a distinction between the two groups. However, this was only effective when reliable brain activations of both tasks were employed simultaneously. Results suggest that deficits in number representation in the visual-parietal cortex get compensated for through finger related aspects of number representation in

  16. Are YouTube videos accurate and reliable on basic life support and cardiopulmonary resuscitation?

    Science.gov (United States)

    Yaylaci, Serpil; Serinken, Mustafa; Eken, Cenker; Karcioglu, Ozgur; Yilmaz, Atakan; Elicabuk, Hayri; Dal, Onur

    2014-10-01

    The objective of this study is to investigate reliability and accuracy of the information on YouTube videos related to CPR and BLS in accord with 2010 CPR guidelines. YouTube was queried using four search terms 'CPR', 'cardiopulmonary resuscitation', 'BLS' and 'basic life support' between 2011 and 2013. Sources that uploaded the videos, the record time, the number of viewers in the study period, inclusion of human or manikins were recorded. The videos were rated if they displayed the correct order of resuscitative efforts in full accord with 2010 CPR guidelines or not. Two hundred and nine videos meeting the inclusion criteria after the search in YouTube with four search terms ('CPR', 'cardiopulmonary resuscitation', 'BLS' and 'basic life support') comprised the study sample subjected to the analysis. Median score of the videos is 5 (IQR: 3.5-6). Only 11.5% (n = 24) of the videos were found to be compatible with 2010 CPR guidelines with regard to sequence of interventions. Videos uploaded by 'Guideline bodies' had significantly higher rates of download when compared with the videos uploaded by other sources. Sources of the videos and date of upload (year) were not shown to have any significant effect on the scores received (P = 0.615 and 0.513, respectively). The videos' number of downloads did not differ according to the videos compatible with the guidelines (P = 0.832). The videos downloaded more than 10,000 times had a higher score than the others (P = 0.001). The majority of You-Tube video clips purporting to be about CPR are not relevant educational material. Of those that are focused on teaching CPR, only a small minority optimally meet the 2010 Resucitation Guidelines. © 2014 Australasian College for Emergency Medicine and Australasian Society for Emergency Medicine.

  17. Life-history variation of a neotropical thrush challenges food limitation theory

    Science.gov (United States)

    Ferretti, V.; Llambias, P.E.; Martin, T.E.

    2005-01-01

    Since David Lack first proposed that birds rear as many young as they can nourish, food limitation has been accepted as the primary explanation for variation in clutch size and other life-history traits in birds. The importance of food limitation in life-history variation, however, was recently questioned on theoretical grounds. Here, we show that clutch size differences between two populations of a neotropical thrush were contrary to expectations under Lack's food limitation hypothesis. Larger clutch sizes were found in a population with higher nestling starvation rate (i.e. greater food limitation). We experimentally equalized clutches between populations to verify this difference in food limitation. Our experiment confirmed greater food limitation in the population with larger mean clutch size. In addition, incubation bout length and nestling growth rate were also contrary to predictions of food limitation theory. Our results demonstrate the inability of food limitation to explain differences in several life-history traits: clutch size, incubation behaviour, parental feeding rate and nestling growth rate. These life-history traits were better explained by inter-population differences in nest predation rates. Food limitation may be less important to life history evolution in birds than suggested by traditional theory. ?? 2005 The Royal Society.

  18. Real-life efficacy and reliability of training a hearing aid.

    Science.gov (United States)

    Keidser, Gitte; Alamudi, Karima

    2013-09-01

    provided valid data after both comparison trials, those who trained the device consistently generally showed consistent preferences, and vice versa. For those who wanted a change to the prescription, training was mostly effective. Limited data on reliability showed reasonable consistency in training outcomes and preferences. Findings, in particular on reliability, should be verified in larger populations. A guideline on how to clinically manage training with clients is presented.

  19. The Brief Multidimensional Students' Life Satisfaction Scale (BMSLSS): Reliability, validity, and gender invariance in an Indian adolescent sample.

    Science.gov (United States)

    Hashim, Jayana; Areepattamannil, Shaljan

    2017-06-01

    This study examined the internal consistency reliability, factorial, convergent, discriminant, and predictive validity, as well as gender invariance of the Brief Multidimensional Students' Life Satisfaction Scale (BMSLSS; Seligson, Huebner, & Valois, 2003) in a sample of 445 adolescents (M age  = 16.04 years) hailing from the southernmost state of India, Kerala. The study also examined the test-retest reliability (n = 392) of the BMSLSS. The Cronbach's alpha coefficient suggested that the BMSLSS was reliable. Confirmatory factor analyses demonstrated the factorial validity of the BMSLSS. Bivariate correlational analyses provided support for the convergent, discriminant, and predictive validity of the BMSLSS. The test-retest reliability coefficient indicated the temporal stability of the BMSLSS. Finally, multi-group confirmatory factor analysis provided support for the gender invariance of the BMSLSS. Copyright © 2017 The Foundation for Professionals in Services for Adolescents. Published by Elsevier Ltd. All rights reserved.

  20. Reliability of the Music in Everyday Life (MEL) Scale: A Parent-Report Assessment for Children on the Autism Spectrum.

    Science.gov (United States)

    Gottfried, Tali; Thompson, Grace; Elefant, Cochavit; Gold, Christian

    2018-06-07

    For young children on the autism spectrum, the inclusion of shared parent-child music activities in everyday life may provide additional opportunities for social interactions in the home. However, no psychometrically validated assessment exists to measure the extent of shared music activity within family or community contexts. This study aimed to develop and test the reliability of a self-report assessment to measure the use of Music in Everyday Life (MEL) by parents with young children on the autism spectrum. A total of 45 mothers of children with autism aged between 4 and 7 years completed the MEL questionnaire. Internal consistency and item-total correlation were examined. Analysis confirmed the reliability of two predetermined subscales: Music in Everyday Life-Joint Activities using Music (MEL-JAM) and Music in Everyday Life-Routine Activities using Music (MEL-RAM). Internal consistency (Cronbach's alpha 0.63 and 0.75) and positive item-total correlation (Pearson's r between .23 to .62 for MEL-JAM and between .30 to .67 for MEL-RAM) were demonstrated. The reliability of the MEL assessment to measure the use of music in everyday life by parents with their children with autism was confirmed, filling an important gap in the availability of assessment tools.

  1. Reliability and limitation of various diagnostic methods including nuclear medicine in myocardial disease

    International Nuclear Information System (INIS)

    Tokuyasu, Yoshiki; Kusakabe, Kiyoko; Yamazaki, Toshio

    1981-01-01

    Electrocardiography (ECG), echocardiography, nuclear method, cardiac catheterization, left ventriculography and endomyocardial biopsy (biopsy) were performed in 40 cases of cardiomyopathy (CM), 9 of endocardial fibroelastosis and 19 of specific heart muscle disease, and the usefulness and limitation of each method was comparatively estimated. In CM, various methods including biopsy were performed. The 40 patients were classified into 3 groups, i.e., hypertrophic (17), dilated (20) and non-hypertrophic.non-dilated (3) on the basis of left ventricular ejection fraction and hypertrophy of the ventricular wall. The hypertrophic group was divided into 4 subgroups: 9 septal, 4 apical, 2 posterior and 2 anterior. The nuclear study is useful in assessing the site of the abnormal ventricular thickening, perfusion defect and ventricular function. Echocardiography is most useful in detecting asymmetric septal hypertrophy. The biopsy gives the sole diagnostic clue, especially in non-hypertrophic.non-dilated cardiomyopathy. ECG is useful in all cases but correlation with the site of disproportional hypertrophy was not obtained. (J.P.N.)

  2. Life Limiting Issues for Long Term Operation of Nuclear Power Plants

    International Nuclear Information System (INIS)

    Esselman, Thomas; Gaertner, John

    2012-01-01

    This paper reports on a study which identified and characterized life limiting issues for consideration by nuclear plant owners in their decision to extend plant life or seek subsequent license renewal. As nuclear plants operate for longer periods, the risk that a condition in the plant or an event that occurs, at the plant or elsewhere, will cause a plant owner not to extend plant life increases. The Fukushima accident has made this concept concrete. This paper defines 'Life Limiting' concepts for nuclear plants. It identifies the highest risk conditions and events that may limit duration of continued operation in nuclear plants and employs a survey to prioritize these concerns. Methods for evaluating these risks and changing the capability of systems, structures, and components (SSC) to reduce and manage this risk in long term operation are presented. Integrated obsolescence -the existence of an accumulation of events or condition that can threaten long term operation- is discussed. Many of the life limiting conditions or events may be controllable by early identification, recognition, and mitigation of the potential threat. The recognition of conditions may allow measures to be taken to mitigate the condition. Recognition of the potential for events that may be life limiting may allow actions to be taken that will minimize the likelihood or consequences of the event. These actions may include enhanced research on the expected behavior of the SSC, risk assessment and management, and enhanced monitoring and aging management at the plant. (author)

  3. [Perspective of intensive care nursing staff on the limitation of life support treatment].

    Science.gov (United States)

    Vallès-Fructuoso, O; Ruiz-de Pablo, B; Fernández-Plaza, M; Fuentes-Milà, V; Vallès-Fructuoso, O; Martínez-Estalella, G

    To determine the perspective of intensive care nursing staff on the limitation of life support treatment (LLST) in the Intensive Care Units. An exploratory qualitative study was carried out by applying the theory of Strauss and Corbin as the analysis tool. Constructivist paradigm. Nursing staff from three Intensive Care Units of Hospital Universitari de Bellvitge. Convenience sampling to reach theoretical saturation of data. Data collection through semi-structured interview recorded prior to informed consent. Rigor and quality criteria (reliability, credibility, transferability), and authenticity criteria: reflexivity. Demographic data was analysed using Excel. A total of 28 interviews were conducted. The mean age of the nurses was 35.6 years, with a mean seniority of 11.46 years of working in ICU. A minority of nurses (21.46%) had received basic training in bioethics. The large majority (85.7%) believe that LLST is not a common practice due to therapeutic cruelty and poor management with it. There is a correlation with the technical concepts; but among the main ethical problems is the decision to apply LLST. Nurses recognise that the decision on applying LLST depends on medical consensus with relatives, and they believe that their opinion is not considered. Their objective is trying to avoid suffering, and assist in providing a dignified death and support to relatives. There is still a paternalistic pattern between the doctor and patient relationship, where the doctor makes the decision and then agrees with the relatives to apply LLST. Organ failure and poor prognosis are the most important criteria for applying LLST. It is necessary to develop a guide for applying LLST, emphasising the involvement of nurses, patients, and their relatives. Copyright © 2016 Elsevier España, S.L.U. y SEEIUC. All rights reserved.

  4. The Persian Version of the "Life Satisfaction Scale": Construct Validity and Test-Re-Test Reliability among Iranian Older Adults.

    Science.gov (United States)

    Moghadam, Manije; Salavati, Mahyar; Sahaf, Robab; Rassouli, Maryam; Moghadam, Mojgan; Kamrani, Ahmad Ali Akbari

    2018-03-01

    After forward-backward translation, the LSS was administered to 334 Persian speaking, cognitively healthy elderly aged 60 years and over recruited through convenience sampling. To analyze the validity of the model's constructs and the relationships between the constructs, a confirmatory factor analysis followed by PLS analysis was performed. The Construct validity was further investigated by calculating the correlations between the LSS and the "Short Form Health Survey" (SF-36) subscales measuring similar and dissimilar constructs. The LSS was re-administered to 50 participants a month later to assess the reliability. For the eight-factor model of the life satisfaction construct, adequate goodness of fit between the hypothesized model and the model derived from the sample data was attained (positive and statistically significant beta coefficients, good R-squares and acceptable GoF). Construct validity was supported by convergent and discriminant validity, and correlations between the LSS and SF-36 subscales. Minimum Intraclass Correlation Coefficient level of 0.60 was exceeded by all subscales. Minimum level of reliability indices (Cronbach's α, composite reliability and indicator reliability) was exceeded by all subscales. The Persian-version of the Life Satisfaction Scale is a reliable and valid instrument, with psychometric properties which are consistent with the original version.

  5. Validity and reliability of the Portuguese-Brazilian version of the Quality of Life in Epilepsy Inventory-89.

    Science.gov (United States)

    Azevedo, Auro Mauro; Alonso, Neide Barreira; Vidal-Dourado, Marcos; Noffs, Maria Helena da Silva; Pascalicchio, Tatiana Frascarelli; Caboclo, Luís Otávio Sales Ferreira; Ciconelli, Rozana Mesquita; Sakamoto, Américo Ceiki; Yacubian, Elza Márcia Targas

    2009-03-01

    The purpose of this article was to report the translation of the Quality of Life in Epilepsy Inventory-89 (QOLIE-89) into a Portuguese-Brazilian version and evaluate its reliability and validity. This study involved 105 outpatients: 54 patients with refractory temporal lobe epilepsy (TLE) with mesial temporal sclerosis (MTS) and 51 with juvenile myoclonic epilepsy (JME). Reliability and test-retest reliability were assessed. Relationships between QOLIE-89 domains and other questionnaires (Nottingham Health Profile, Beck Depression Inventory, Adverse Event Profile, Neuropsychological Evaluation), and external measures such as demographic and clinical variables were analyzed to examine construct validity. Internal consistency (Cronbach's alpha=0.73-0.92) and test-retest reliability (intraclass correlation coefficient=0.60-0.84) for individual domains were acceptable. For construct validity, we verified high correlations between the QOLIE-89 and the Nottingham Health Profile, Beck Depression Inventory, Adverse Event Profile, and Neuropsychological Evaluation. For clinical characteristics, the patients with juvenile myoclonic epilepsy had better quality-of-life scores on 11 of 17 QOLIE-89 subscales compared with patients with temporal lobe epilepsy (P<0.05). These results support the reliability and validity of the Portuguese-Brazilian translation of QOLIE-89.

  6. Functional claudication distance: a reliable and valid measurement to assess functional limitation in patients with intermittent claudication

    Directory of Open Access Journals (Sweden)

    Prins Martin H

    2009-03-01

    Full Text Available Abstract Background Disease severity and functional impairment in patients with intermittent claudication is usually quantified by the measurement of pain-free walking distance (intermittent claudication distance, ICD and maximal walking distance (absolute claudication distance, ACD. However, the distance at which a patient would prefer to stop because of claudication pain seems a definition that is more correspondent with the actual daily life walking distance. We conducted a study in which the distance a patient prefers to stop was defined as the functional claudication distance (FCD, and estimated the reliability and validity of this measurement. Methods In this clinical validity study we included patients with intermittent claudication, following a supervised exercise therapy program. The first study part consisted of two standardised treadmill tests. During each test ICD, FCD and ACD were determined. Primary endpoint was the reliability as represented by the calculated intra-class correlation coefficients. In the second study part patients performed a standardised treadmill test and filled out the Rand-36 questionnaire. Spearman's rho was calculated to assess validity. Results The intra-class correlation coefficients of ICD, FCD and ACD were 0.940, 0.959, and 0.975 respectively. FCD correlated significantly with five out of nine domains, namely physical function (rho = 0.571, physical role (rho = 0.532, vitality (rho = 0.416, pain (rho = 0.416 and health change (rho = 0.414. Conclusion FCD is a reliable and valid measurement for determining functional capacity in trained patients with intermittent claudication. Furthermore it seems that FCD better reflects the actual functional impairment. In future studies, FCD could be used alongside ICD and ACD.

  7. 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.

  8. Assessment of Advanced Life Support competence when combining different test methods--reliability and validity

    DEFF Research Database (Denmark)

    Ringsted, C; Lippert, F; Hesselfeldt, R

    2007-01-01

    Cardiac Arrest Simulation Test (CASTest) scenarios for the assessments according to guidelines 2005. AIMS: To analyse the reliability and validity of the individual sub-tests provided by ERC and to find a combination of MCQ and CASTest that provides a reliable and valid single effect measure of ALS...... that possessed high reliability, equality of test sets, and ability to discriminate between the two groups of supposedly different ALS competence. CONCLUSIONS: ERC sub-tests of ALS competence possess sufficient reliability and validity. A combined ALS score with equal weighting of one MCQ and one CASTest can...... competence. METHODS: Two groups of participants were included in this randomised, controlled experimental study: a group of newly graduated doctors, who had not taken the ALS course (N=17) and a group of students, who had passed the ALS course 9 months before the study (N=16). Reliability in terms of inter...

  9. Aircraft Engine Life-Consumption Monitoring for Real-Time Reliability Determination, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — The object of this research is to develop an in-service life-monitor system for the prediction of the remaining component and system life of aircraft engines. The...

  10. Evaluating the Impact of Conservatism in Industrial Fatigue Analysis of Life-Limited Components

    Directory of Open Access Journals (Sweden)

    Hoole Joshua

    2018-01-01

    Full Text Available This paper presents a review of the conservatism approaches applied by different industrial sectors to the stress-life (S-N analysis of ‘life-limited’ or ‘safe-life’ components. A comparison of the fatigue design standards for 6 industrial sectors identified that the conservatism approaches are highly inconsistent when comparing the areas of variability and uncertainty accounted for along with the conservatism magnitude and method of application. Through the use of a case-study based on the SAE keyhole benchmark and 4340 steel S-N data, the industrial sector which introduces the greatest reduction of a component life-limit was identified as the nuclear sector. The results of the case-study also highlighted that conservatism applied to account for scatter in S-N data currently provides the greatest contribution to the reduction of component life-limits.

  11. Faith, Hope, and Spirituality: SUPPORTING PARENTS WHEN THEIR CHILD HAS A LIFE-LIMITING ILLNESS.

    Science.gov (United States)

    Crisp, Cheryl L

    2016-01-01

    When a child has a life-limiting illness, parents' goals and strategies for their child's life may need to be drastically altered, especially if early death looms. This article reviews literature and research about how families employ faith, hope, spirituality, and biblical perspectives as their child becomes critically ill and faces death. Suggestions are made for best caring practices for families and children encountering this difficult journey.

  12. The validity and reliability of Systemic Lupus Erythematosus Quality of Life Questionnaire (L-QoL) in a Turkish population.

    Science.gov (United States)

    Duruöz, M T; Unal, C; Toprak, C Sanal; Sezer, I; Yilmaz, F; Ulutatar, F; Atagündüz, P; Baklacioglu, H S

    2017-12-01

    Background Systemic lupus erythematosus (SLE) may have a profound impact on quality of life. There is increasing interest in measuring quality of life in lupus patients. The purpose of this study was to investigate the validity and reliability of SLE Quality of Life Questionnaire (L-QoL) in Turkish SLE patients. Methods SLE according to 2012 Systemic Lupus International Collaborating Clinics Classification Criteria were recruited into the study. Demographic data, clinical parameters and disease activity measured with the Systemic Lupus Erythematosus Disease Activity Index-2000 (SLEDAI-2K); were noted. Nottingham Health Profile and Health Assessment Questionnaire were filled out in addition to the Turkish L-QoL (LQoL-TR). Internal consistency, test-retest reliability, and convergent and discriminant validity were evaluated. Results The mean age of participants was 43.55 ± 14.33 years and the mean disease duration was 89.8 ± 92.1 months. The patients filled out LQoL-TR in 2.5 min. Strong correlation of LQoL-TR with all subgroups of the Nottingham Health Profile and the Health Assessment Questionnaire were established showing the convergent validity. The highest correlation was demonstrated with emotional reactions (rho = 0.72) and sleep component (rho = 0.65) of the Nottingham Health Profile scale ( p < 0.0001). Its poor and not significant correlation with nonfunctional parameters (age, disease duration, perceived general health, SLEDAI-2K) showed its discriminative properties. LQoL-TR demonstrated good internal reliability with a Cronbach's α of 0.93 and test-retest reliability with intraclass correlation coefficient of 0.87. Conclusion The LQoL-TR is a practical and useful tool which demonstrates good validity and reliability.

  13. The European Portuguese WHOQOL-OLD module and the new facet Family/Family life: reliability and validity studies.

    Science.gov (United States)

    Vilar, Manuela; Sousa, Liliana B; Simões, Mário R

    2016-09-01

    The aim of this study was to examine the psychometric properties of the European Portuguese version of the World Health Organization Quality of Life-Older Adults Module (WHOQOL-OLD). The European Portuguese WHOQOL-OLD includes a new identified facet, Family/Family life. A convenience sample of older adults was recruited (N = 921). The assessment protocol included demographics, self-perceived health, depressive symptoms (GDS-30), cognitive function (ACE-R), daily life activities (IAFAI), health status (SF-12) and QoL (WHOQOL-Bref, EUROHIS-QOL-8 and WHOQOL-OLD). The internal consistency was excellent for the total 24-item WHOQOL-OLD original version and also for the final 28-item European Portuguese WHOQOL-OLD version. The test-retest reliability for total scores was good. The construct validity of the European Portuguese WHOQOL-OLD was supported in the correlation matrix analysis. The results indicated good convergent/divergent validity. The WHOQOL-OLD scores differentiated groups of older adults who were healthy/unhealthy and without/mild/severe depressive symptoms. The new facet, Family/Family life, presented evidence of good reliability and validity parameters. Comparatively to international studies, the European Portuguese WHOQOL-OLD version showed similar and/or better psychometric properties. The new facet, Family/Family life, introduces cross-cultural specificity to the study of QoL of older adults and generally improves the psychometric robustness of the WHOQOL-OLD.

  14. The Toronto outcome measure for craniofacial prosthetics: reliability and validity of a condition-specific quality-of-life instrument.

    Science.gov (United States)

    Anderson, James D; Johnston, Dennis A; Haugh, Gil S; Kiat-Amnuay, Sudarat; Gettleman, Lawrence

    2013-01-01

    The purpose of this study was to refine the Toronto Outcome Measure for Craniofacial Prosthetics (TOMCP), present evidence for its reliability and validity, and use the instrument to explore differences in quality of life between prostheses made with chlorinated polyethylene (CPE) (experimental) and silicone (control). As part of a multicenter prospective controlled randomized double-blind single-crossover clinical trial of the two materials, the TOMCP was administered at the start and end of two 4-month study arms, during which 42 patients wore prostheses made from one material then the other. Reliability was assessed at the crossover. To determine validity of the TOMCP, the Linear Analogue Self-Assessment (LASA-12) and the Short-Form 8 (SF-8) were also administered with the TOMCP. The TOMCP was reduced by removing items that were unreliable, had poorly distributed answers, showed increased internal consistency after their removal, or were too highly correlated with more than one other item. The tests of reliability and validity were then repeated. Finally, the reduced instrument was used to test for differences in quality of life between prostheses made of the two materials. The item reduction tactics pared the 52-item instrument down to 27 items. The correlations of both TOMCP versions with the LASA-12 and the SF-8 were found to be statistically significant, providing evidence of the validity of the TOMCP. The instrument revealed significantly better quality of life with silicone rather than CPE prostheses. Both versions of the TOMCP were found to be reliable and valid. The instrument was able to show differences in quality of life between two materials.

  15. The Validity and Reliability Test of the Indonesian Version of Gastroesophageal Reflux Disease Quality of Life (GERD-QOL) Questionnaire.

    Science.gov (United States)

    Siahaan, Laura A; Syam, Ari F; Simadibrata, Marcellus; Setiati, Siti

    2017-01-01

    to obtain a valid and reliable GERD-QOL questionnaire for Indonesian application. at the initial stage, the GERD-QOL questionnaire was first translated into Indonesian language and the translated questionnaire was subsequently translated back into the original language (back-to-back translation). The results were evaluated by the researcher team and therefore, an Indonesian version of GERD-QOL questionnaire was developed. Ninety-one patients who had been clinically diagnosed with GERD based on the Montreal criteria were interviewed using the Indonesian version of GERD-QOL questionnaire and the SF 36 questionnaire. The validity was evaluated using a method of construct validity and external validity, and reliability can be tested by the method of internal consistency and test retest. the Indonesian version of GERD-QOL questionnaire had a good internal consistency reliability with a Cronbach Alpha of 0.687-0.842 and a good test retest reliability with an intra-class correlation coefficient of 0.756-0.936; pGERD-QOL questionnaire has been proven valid and reliable to evaluate the quality of life of GERD patients.

  16. [Development of social activities-related daily life satisfaction scale for the elderly and evaluation of its reliability and validity].

    Science.gov (United States)

    Okamoto, Hideaki

    2010-07-01

    The purpose of this study was to develop a Social Activities-Related Daily Life Satisfaction Scale specifically applicable to elderly people in communities and to evaluate its reliability and validity. Sixteen items were extracted from an initial pool and assessed for inclusion in the scale by correlation and exploratory factor analyses. To confirm validity, confirmatory factor analysis was conducted and correlation coefficients were calculated. In addition, t-tests were performed in order to generate scores of the subscale related to activity. To prove reliability, Cronbach's coefficient alpha values were calculated. Data for 755 older adults aged 65 to 84 years were obtained from a mail survey in Ichikawa City, Chiba Prefecture. Exploratory factor analyses indicated that four factors, "satisfaction with learning" (four items), "satisfaction with usefulness to others and society" (four items), "satisfaction with health and physical strength" (three items), and "satisfaction with friends" (three items) should be extracted. Confirmatory factor analysis for assessing the 14-item four-factor model showed high goodness of fit indices (GFI = 0.943, AGFI = 0.915, RMSEA = 0.068). Concurrent validity was established by comparing the score of the scale with five external variables (Activity and Daily Life Satisfaction Scale for the Elderly, Life Satisfaction Index K, etc). Student's t-tests revealed that each score of the subscale was positively associated with activity variable. The overall Cronbach's coefficient alpha for the scale was 0.919 and for its four subscales values ranged from 0.814 to 0.887. A Social Activities-Related Daily Life Satisfaction Scale was derived consisting of four subscales, "satisfaction with learning", "satisfaction with usefulness to others and society", "satisfaction with health and physical strength", and "satisfaction with friends". The results of the present study suggested that the Social Activities-Related Daily Life Satisfaction Scale

  17. Designing high availability systems DFSS and classical reliability techniques with practical real life examples

    CERN Document Server

    Taylor, Zachary

    2014-01-01

    A practical, step-by-step guide to designing world-class, high availability systems using both classical and DFSS reliability techniques Whether designing telecom, aerospace, automotive, medical, financial, or public safety systems, every engineer aims for the utmost reliability and availability in the systems he, or she, designs. But between the dream of world-class performance and reality falls the shadow of complexities that can bedevil even the most rigorous design process. While there are an array of robust predictive engineering tools, there has been no single-source guide to understan

  18. An Integrated Health Monitoring Method for Structural Fatigue Life Evaluation Using Limited Sensor Data

    Directory of Open Access Journals (Sweden)

    Jingjing He

    2016-11-01

    Full Text Available A general framework for structural fatigue life evaluation under fatigue cyclic loading using limited sensor data is proposed in this paper. First, limited sensor data are measured from various sensors which are preset on the complex structure. Then the strain data at remote spots are used to obtain the strain responses at critical spots by the strain/stress reconstruction method based on empirical mode decomposition (REMD method. All the computations in this paper are directly performed in the time domain. After the local stress responses at critical spots are determined, fatigue life evaluation can be performed for structural health management and risk assessment. Fatigue life evaluation using the reconstructed stresses from remote strain gauge measurement data is also demonstrated with detailed error analysis. Following this, the proposed methodology is demonstrated using a three-dimensional frame structure and a simplified airfoil structure. Finally, several conclusions and future work are drawn based on the proposed study.

  19. Development, validity and reliability testing of the East Midlands Evaluation Tool (EMET) for measuring impacts on trainees' confidence and competence following end of life care training.

    Science.gov (United States)

    Whittaker, B; Parry, R; Bird, L; Watson, S; Faull, C

    2017-02-02

    To develop, test and validate a versatile questionnaire, the East Midlands Evaluation Tool (EMET), for measuring effects of end of life care training events on trainees' self-reported confidence and competence. A paper-based questionnaire was designed on the basis of the English Department of Health's core competences for end of life care, with sections for completion pretraining, immediately post-training and also for longer term follow-up. Preliminary versions were field tested at 55 training events delivered by 13 organisations to 1793 trainees working in diverse health and social care backgrounds. Iterative rounds of development aimed to maximise relevance to events and trainees. Internal consistency was assessed by calculating interitem correlations on questionnaire responses during field testing. Content validity was assessed via qualitative content analysis of (1) responses to questionnaires completed by field tester trainers and (2) field notes from a workshop with a separate cohort of experienced trainers. Test-retest reliability was assessed via repeat administration to a cohort of student nurses. The EMET comprises 27 items with Likert-scaled responses supplemented with questions seeking free-text responses. It measures changes in self-assessed confidence and competence on 5 subscales: communication skills; assessment and care planning; symptom management; advance care planning; overarching values and knowledge. Test-retest reliability was found to be good, as was internal consistency: the questions successfully assess different aspects of the same underlying concept. The EMET provides a time-efficient, reliable and flexible means of evaluating effects of training on self-reported confidence and competence in the key elements of end of life care. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

  20. Understanding reliability and some limitations of the images and spectra reconstructed from a multi-monochromatic x-ray imager

    Science.gov (United States)

    Nagayama, T.; Mancini, R. C.; Mayes, D.; Tommasini, R.; Florido, R.

    2015-11-01

    Temperature and density asymmetry diagnosis is critical to advance inertial confinement fusion (ICF) science. A multi-monochromatic x-ray imager (MMI) is an attractive diagnostic for this purpose. The MMI records the spectral signature from an ICF implosion core with time resolution, 2-D space resolution, and spectral resolution. While narrow-band images and 2-D space-resolved spectra from the MMI data constrain temperature and density spatial structure of the core, the accuracy of the images and spectra depends not only on the quality of the MMI data but also on the reliability of the post-processing tools. Here, we synthetically quantify the accuracy of images and spectra reconstructed from MMI data. Errors in the reconstructed images are less than a few percent when the space-resolution effect is applied to the modeled images. The errors in the reconstructed 2-D space-resolved spectra are also less than a few percent except those for the peripheral regions. Spectra reconstructed for the peripheral regions have slightly but systematically lower intensities by ˜6% due to the instrumental spatial-resolution effects. However, this does not alter the relative line ratios and widths and thus does not affect the temperature and density diagnostics. We also investigate the impact of the pinhole size variation on the extracted images and spectra. A 10% pinhole size variation could introduce spatial bias to the images and spectra of ˜10%. A correction algorithm is developed, and it successfully reduces the errors to a few percent. It is desirable to perform similar synthetic investigations to fully understand the reliability and limitations of each MMI application.

  1. Understanding reliability and some limitations of the images and spectra reconstructed from a multi-monochromatic x-ray imager

    International Nuclear Information System (INIS)

    Nagayama, T.; Mancini, R. C.; Mayes, D.; Tommasini, R.; Florido, R.

    2015-01-01

    Temperature and density asymmetry diagnosis is critical to advance inertial confinement fusion (ICF) science. A multi-monochromatic x-ray imager (MMI) is an attractive diagnostic for this purpose. The MMI records the spectral signature from an ICF implosion core with time resolution, 2-D space resolution, and spectral resolution. While narrow-band images and 2-D space-resolved spectra from the MMI data constrain temperature and density spatial structure of the core, the accuracy of the images and spectra depends not only on the quality of the MMI data but also on the reliability of the post-processing tools. Here, we synthetically quantify the accuracy of images and spectra reconstructed from MMI data. Errors in the reconstructed images are less than a few percent when the space-resolution effect is applied to the modeled images. The errors in the reconstructed 2-D space-resolved spectra are also less than a few percent except those for the peripheral regions. Spectra reconstructed for the peripheral regions have slightly but systematically lower intensities by ∼6% due to the instrumental spatial-resolution effects. However, this does not alter the relative line ratios and widths and thus does not affect the temperature and density diagnostics. We also investigate the impact of the pinhole size variation on the extracted images and spectra. A 10% pinhole size variation could introduce spatial bias to the images and spectra of ∼10%. A correction algorithm is developed, and it successfully reduces the errors to a few percent. It is desirable to perform similar synthetic investigations to fully understand the reliability and limitations of each MMI application

  2. Understanding reliability and some limitations of the images and spectra reconstructed from a multi-monochromatic x-ray imager.

    Science.gov (United States)

    Nagayama, T; Mancini, R C; Mayes, D; Tommasini, R; Florido, R

    2015-11-01

    Temperature and density asymmetry diagnosis is critical to advance inertial confinement fusion (ICF) science. A multi-monochromatic x-ray imager (MMI) is an attractive diagnostic for this purpose. The MMI records the spectral signature from an ICF implosion core with time resolution, 2-D space resolution, and spectral resolution. While narrow-band images and 2-D space-resolved spectra from the MMI data constrain temperature and density spatial structure of the core, the accuracy of the images and spectra depends not only on the quality of the MMI data but also on the reliability of the post-processing tools. Here, we synthetically quantify the accuracy of images and spectra reconstructed from MMI data. Errors in the reconstructed images are less than a few percent when the space-resolution effect is applied to the modeled images. The errors in the reconstructed 2-D space-resolved spectra are also less than a few percent except those for the peripheral regions. Spectra reconstructed for the peripheral regions have slightly but systematically lower intensities by ∼6% due to the instrumental spatial-resolution effects. However, this does not alter the relative line ratios and widths and thus does not affect the temperature and density diagnostics. We also investigate the impact of the pinhole size variation on the extracted images and spectra. A 10% pinhole size variation could introduce spatial bias to the images and spectra of ∼10%. A correction algorithm is developed, and it successfully reduces the errors to a few percent. It is desirable to perform similar synthetic investigations to fully understand the reliability and limitations of each MMI application.

  3. 41 CFR 102-33.370 - What must we do to dispose of military FSCAP or life-limited parts?

    Science.gov (United States)

    2010-07-01

    ... before you exchange or sell the aircraft or engine (see rules for disposing of uninstalled life-limited... dispose of military FSCAP or life-limited parts? 102-33.370 Section 102-33.370 Public Contracts and... Aircraft Parts Special Requirements for Disposing of Flight Safety Critical Aircraft Parts (fscap) and Life...

  4. Validity and reliability of the Portuguese version of the quality of life in epilepsy inventory (QOLIE-31) for Brazil.

    Science.gov (United States)

    da Silva, Tatiana Indelicato; Ciconelli, Rozana Mesquita; Alonso, Neide Barreira; Azevedo, Auro Mauro; Westphal-Guitti, Ana Carolina; Pascalicchio, Tatiana Frascarelli; Marques, Carolina Mattos; Caboclo, Luís Otávio Sales Ferreira; Cramer, Joyce A; Sakamoto, Américo Ceiki; Yacubian, Elza Márcia Targas

    2007-03-01

    We report the cultural adaptation and psychometric properties of the Quality of Life in Epilepsy-31 Inventory (QOLIE-31) for the Portuguese language and Brazilian culture. This study involved 150 outpatients: 50 presurgical patients with refractory temporal lobe epilepsy (TLE) related to mesial temporal sclerosis (MTS), 50 patients with juvenile myoclonic epilepsy (JME), and 50 seizure-free patients with TLE. They completed the QOLIE-31, Nottingham Health Profile (NHP), Beck Depression Inventory (BDI), and Adverse Events Profile (AEP) and underwent a neuropsychological evaluation (NE). Internal consistency reliability, interrater and test-retest reliability, and construct validity were assessed. QOLIE-31 mean scores were 33.1 (Social Function), 68.9 (Overall Quality of Life), 56.5 (Seizure Worry), 64.1 (Emotional Well-Being), 63.7 (Energy/Fatigue), 38.9 (Cognitive Function), and 49.7 (Medication Effects). Internal consistency was high (Cronbach's alpha), as were the associations between QOLIE-31 and the BDI, NHP, AEP, and NE. The Portuguese/Brazilian version of the QOLIE-31 inventory showed good reliability, validity, and construct validity.

  5. [Development and reliability evaluation of an instrument to measure health-related quality of life in independent elderly].

    Science.gov (United States)

    Lima, Maria José Barbosa de; Portela, Margareth Crisóstomo

    2010-08-01

    This study presents an instrument, the health-related quality of life (HRQOL) profile for independent elderly, to measure the health-related quality of life of the functionally independent elderly assisted in the outpatient setting, based on the adaptation of four validated scales: Short-Form Health Survey (SF-36), Duke-UNC Health Profile (DUHP), Sickness Impact Profile (SIP), and Nottingham Health Profile (NHP). The study also evaluates the instrument's reliability based on its use by two different observers with a 15-day interval. The instrument includes five dimensions (health perception, symptoms, physical function, psychological function, and social function) and 45 items. Reliability evaluation of the QUASI instrument was based on interviews with 142 elderly outpatients in the city of Rio de Janeiro, Brazil. Prevalence-adjusted kappa statistic was used to assess all 45 items. Correlation was also calculated between overall scores and scores on individual dimensions. In the reliability evaluation, 39 of the 45 items showed prevalence-adjusted kappa greater than 0.60.

  6. Fuel channel life limiting factors that dictate fuel channel maintenance requirements

    International Nuclear Information System (INIS)

    Richinson, P.J.; Wong, H.W.; Ellis, P.J.

    1995-01-01

    CANDU reactors have been operating for 33 years. The Nuclear Power Demonstration (NPD) Unit started up in 1962 and the prototype of CANDU, Douglas Point, started in 1967. The first commercial reactors, Pickering Units 1 and 2 both went into service in 1971 closely followed by Units 3 and 4 in 1972 and 1973 respectively. Operating commercial reactor experience represents over 10,000 pressure tubes, not including the replaced channels in all the Pickering A Units, and nearly 130,000 pressure tube operating years. No pressure tube has yet operated for its 30 year design lifetime of 210 KEFPH at 80% capacity factor. The longest operating time for pressure tubes to-date is about 120 KEFPH in Pickering Unit 4. Many lessons have been learned regarding pressure tube life limiting factors from the early CANDU units and these, together with the information obtained from an extensive pressure tube R and D program, have resulted in many design changes and improvements in material properties, mainly from manufacturing route changes. Reactors built recently are expected to achieve their 30 year design life. The development of Periodic and In-service Inspection programs and equipment, assessment methodologies and acceptance criteria, and the development of maintenance tooling and procedures are enabling the life limiting factors to be addressed in the currently operating units. The life limiting factors in currently operating Units are reviewed in relation to the experience gained from the early units, the R and D programs and the inspection and maintenance performed to date. (author)

  7. The experience of Chinese American parents of children with life-limiting illness: a comprehensive review.

    Science.gov (United States)

    Wang, Jinjiao; Kearney, Joan A

    2013-07-01

    Life-limiting childhood illness is a traumatic experience presenting parents with psychological, physical, and social challenges. While cultural influences affect all parents coping with the life-limiting illness and end-of-life period of their child, little is known about the experiences of Chinese American parents. The purpose of this comprehensive literature review was to describe Chinese American parents' experiences during their children's end-of-life period from a culturally informed perspective. Important themes in the literature are revealed including culture-based phenomena regarding philosophy of life and illness that can affect treatment choices, cultural mores that influence parental behaviour in Western health-care systems, specific communication patterns within families and between families and providers, certain coping risks, and gender-based roles and caregiving activities that have implications for provider communication patterns. The findings are consonant with the larger literature regarding the impact of traditional culture and values on Chinese family and health behaviours. Health professionals must be sensitive to Chinese American parents' communication styles, unspoken concerns, and unresolved cultural conflicts in American health-care settings. Educational interventions may be very helpful in this regard.

  8. An Introduction To Reliability

    International Nuclear Information System (INIS)

    Park, Kyoung Su

    1993-08-01

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

  9. Reliability and validity of the PHQ-9 for screening late-life depression in Chinese primary care.

    Science.gov (United States)

    Chen, Shulin; Chiu, Helen; Xu, Baihua; Ma, Yan; Jin, Tao; Wu, Manhua; Conwell, Yeates

    2010-11-01

    The aim of this study was to examine the reliability and validation of the 9-item Patient Health Questionnaire (PHQ-9) for late-life depression in Chinese primary care. In the primary care clinics (PCCs) of Hangzhou city, we recruited 364 older patients (aged ≥ 60) for the PHQ-9 screening. Then 77 of them were further interviewed with Structured Clinical Interview for DSM Disorders (SCID) for the diagnosis of major depression in late life. Statistic strategies for the feasibility, reliability, validity, and receiver operating characteristic curve were performed. The mean administration time was 7.5 min, and the Cronbach's α was 0.91. The optimal cut-off score of PHQ-9 ≥ 9 revealed a sensitivity of 0.86, specificity of 0.77, and positive likelihood ratio of 5.73. The area under the curve (AUC) in this study was 0.92 (SD = 0.02, 95% CI 0.88-0.96). The PHQ-2 also revealed good sensitivity (0.84) and specificity (0.90) at the cut-off point ≥ 3. The PHQ-9 performs well and has acceptable psychometric properties for screening of patients with late-life depression in Chinese primary care settings.

  10. Reliability considerations in long-life outer planet spacecraft system design

    Science.gov (United States)

    Casani, E. K.

    1975-01-01

    A Mariner Jupiter/Saturn mission has been planned for 1977. System reliability questions are discussed, taking into account the actual and design lifetime, causes of mission termination, in-flight failures and their consequences for the mission, and the use of redundancy to avoid failures. The design process employed optimizes the use of proven subsystem and system designs and then makes the necessary improvements to increase the lifetime as required.

  11. Sensory shelf-life limiting factor of high hydrostatic pressure processed avocado paste.

    Science.gov (United States)

    Jacobo-Velázquez, D A; Hernández-Brenes, C

    2011-08-01

    High hydrostatic pressure (HHP) processing pasteurizes avocado paste without a significant impact on flavor. Although HHP-treated avocado paste stored under refrigeration is safe for human consumption for months, sensory changes taking place during storage cause the rejection of the product by consumers within days. Although it is known that the shelf life of the product ends before its microbial counts are high, its sensory shelf life limiting factor remains unknown. The present study focused on the use of a trained panel and a consumer panel to determine the sensory shelf life limiting factor of HHP-treated avocado paste. The trained panel identified sour and rancid flavors as the main sensory descriptors (critical descriptors) that differentiated stored from freshly processed samples. Further data obtained from consumers identified sour flavor as the main cause for a significant decrease in the acceptability (shelf life limiting factor) of refrigerated HHP-treated avocado paste. The study allowed the elucidation of a proposed deterioration mechanism for HHP-treated avocado paste during its refrigerated shelf life. The information through this work enhances scientific knowledge of the product and proposes the sour flavor development during storage as a relevant sensory attribute that needs to be improved in order to enhance the product shelf life. At present, HHP is the most effective commercial nonthermal technology to process avocado paste when compared to thermal and chemical alternatives. HHP-treated avocado paste is a microbiologically stable food for a period of at least 45 d stored under refrigeration. However, previous published work indicated that consumers rejected the product after approximately 19 d of storage due to sensory changes. This manuscript presents a sensory study that permitted the identification of the critical sensory descriptor that is acting as the sensory shelf life limiting factor of the product. The data presented herein along with

  12. Closing in on the limits of life through open-access instrumentation.

    Science.gov (United States)

    Girguis, P. R.; Hoer, D.

    2016-12-01

    Put simply, metabolic activity by living organisms can discriminate against elemental isotopes, resulting in an isotopic fractionation that is manifest in their biomolecules, substrates and endproducts. For decades, investigators have used these isotope ratios to make inferences about organismal activity and physiological capacity in modern day and paleo-environments. However, a long standing challenge in the life sciences is identifying and characterizing the limits of life. Whereas the limits of metazoan (animal) life are known to some degree, the extent of microbial life remains unconstrained. For example, we do not know the upper temperature limits of life, nor the lower energy limits of life. Discrete samples and the subsequent geochemical and biological measurements provide a means of bounding these questions, but there are major challenges associated with collecting such samples from the deep sea and other "extreme" habitats. A complementary approach is in situ geo-referenced isotope mapping. To date, we have developed instruments capable of measuring methane-carbon isotope ratios in situ and used the to "map" the activity and influence of anaerobic methanotrophs around natural hydrocarbon seeps (Wankel et al., 2012). While these instruments provide isotopic data in realtime, their greatest value is in producing geo-referenced "maps" of these isotope ratios, enabling investigators to better understand where microbial activity is highest, and the extent to which methane-derived carbon is found in the neighboring sediments and overlying water column. Now, our efforts are aimed at developing a 2nd generation instrument that will be substantially smaller and far more energy efficient, enabling deployment in more challenging environments such as boreholes and beneath ice. Most importantly, we are designing it to be capable of quantifying differences in the isotopes of multiple volatile compounds, e.g. carbon and sulfur, enabling a greater degree of fidelity in

  13. Validity, reliability and responsiveness of the Body Image Quality of Life Inventory in patients treated for infective endocarditis

    DEFF Research Database (Denmark)

    Rasmussen, Trine Bernholdt; Konradsen, Hanne; Dixon, Jane

    2017-01-01

    been validated in this patient population. The purpose of this study was thus to assess the validity, reliability and responsiveness of the Danish Body Image Quality of Life Inventory (BIQLI-DA) on patients treated for IE. METHODS: We evaluated the psychometric properties of the BIQLI-DA on data......: The BIQLI-DA may be applicable in healthcare research as it seems to be valid, reliable and responsive; however, evidence should be strengthened through further exploration of instrument performance, particularly regarding responsiveness.......: Participants were seventy patients with a mean age of 58 years and of which 83% were men. Results indicated convergent construct validity by confirming hypothesised associations to potentially related constructs. The BIQLI-DA was found to be highly internally consistent with a Cronbach's alpha of 0...

  14. Using the Reliability Theory for Assessing the Decision Confidence Probability for Comparative Life Cycle Assessments.

    Science.gov (United States)

    Wei, Wei; Larrey-Lassalle, Pyrène; Faure, Thierry; Dumoulin, Nicolas; Roux, Philippe; Mathias, Jean-Denis

    2016-03-01

    Comparative decision making process is widely used to identify which option (system, product, service, etc.) has smaller environmental footprints and for providing recommendations that help stakeholders take future decisions. However, the uncertainty problem complicates the comparison and the decision making. Probability-based decision support in LCA is a way to help stakeholders in their decision-making process. It calculates the decision confidence probability which expresses the probability of a option to have a smaller environmental impact than the one of another option. Here we apply the reliability theory to approximate the decision confidence probability. We compare the traditional Monte Carlo method with a reliability method called FORM method. The Monte Carlo method needs high computational time to calculate the decision confidence probability. The FORM method enables us to approximate the decision confidence probability with fewer simulations than the Monte Carlo method by approximating the response surface. Moreover, the FORM method calculates the associated importance factors that correspond to a sensitivity analysis in relation to the probability. The importance factors allow stakeholders to determine which factors influence their decision. Our results clearly show that the reliability method provides additional useful information to stakeholders as well as it reduces the computational time.

  15. Patient Assessment of Constipation Quality of Life Questionnaire: Translation, Cultural Adaptation, Reliability, and Validity of the Persian Version.

    Science.gov (United States)

    Nikjooy, Afsaneh; Jafari, Hassan; Saba, Maryam A; Ebrahimi, Naghmeh; Mirzaei, Rezvan

    2018-05-01

    The Patient Assessment of Constipation Quality of Life (PAC-QOL) questionnaire is the most validated and the most specific tool for measuring the quality of life of patients with constipation. Over 120 million people live in countries whose official language is Persian. There is no reported Persian version of the PAC-QOL questionnaire yet. The aim of this study was to translate and culturally adapt the PAC-QOL questionnaire and to assess its reliability and validity among Persian patients with chronic constipation. Following the translation and cultural adaptation of the PAC-QOL questionnaire to Persian, 100 patients (mean±SD age=40.51±13.67) with constipation were recruited for validity measurement and 20 patients were re-examined for reliability. Content validity was assessed based on the opinions of an expert committee and the floor/ceiling effect. Construct validity was evaluated according to the hypothesis test. The SF-36 questionnaire was used for concurrent criterion validity, intra-class correlation coefficient for reliability, and Cronbach's alpha for internal consistency. The content validity of the PAC-QOL questionnaire was proven, and there was no floor/ceiling effect. Construct validity also was confirmed based on the hypothesis test. The overall Cronbach's alpha of the PAC-QOL questionnaire was 0.92 (range=0.72-0.92), and the overall intra-class correlation coefficient of the questionnaire was 0.88 (range=0.69-0.87). The correlation between the SF-36 and PAC-QOL questionnaires was moderate. The Persian version of the PAC-QOL questionnaire demonstrated good validity and reliability properties in chronic constipation. Accordingly, Persian researchers and clinicians can benefit from this questionnaire in further research and assessment of treatment outcomes.

  16. Identification of fall risk predictors in daily life measurements: gait characteristics' reliability and association with self-reported fall history.

    Science.gov (United States)

    Rispens, Sietse M; van Schooten, Kimberley S; Pijnappels, Mirjam; Daffertshofer, Andreas; Beek, Peter J; van Dieën, Jaap H

    2015-01-01

    Background. Gait characteristics extracted from trunk accelerations during daily life locomotion are complementary to questionnaire- or laboratory-based gait and balance assessments and may help to improve fall risk prediction. Objective. The aim of this study was to identify gait characteristics that are associated with self-reported fall history and that can be reliably assessed based on ambulatory data collected during a single week. Methods. We analyzed 2 weeks of trunk acceleration data (DynaPort MoveMonitor, McRoberts) collected among 113 older adults (age range, 65-97 years). During episodes of locomotion, various gait characteristics were determined, including local dynamic stability, interstride variability, and several spectral features. For each characteristic, we performed a negative binomial regression analysis with the participants' self-reported number of falls in the preceding year as outcome. Reliability of gait characteristics was assessed in terms of intraclass correlations between both measurement weeks. Results. The percentages of spectral power below 0.7 Hz along the vertical and anteroposterior axes and below 10 Hz along the mediolateral axis, as well as local dynamic stability, local dynamic stability per stride, gait smoothness, and the amplitude and slope of the dominant frequency along the vertical axis, were associated with the number of falls in the preceding year and could be reliably assessed (all P 0.75). Conclusions. Daily life gait characteristics are associated with fall history in older adults and can be reliably estimated from a week of ambulatory trunk acceleration measurements. © The Author(s) 2014.

  17. Life beyond the limits of knowledge: crystalline life in the popular science of Desiderius Papp (1895-1993).

    Science.gov (United States)

    Brandstetter, Thomas

    2012-10-01

    The aim of this article is to show how, and in which context, astrobiological reasoning was employed before the establishment of astrobiology as a scientific discipline. By way of an example, I will discuss a popular science book published in 1931 by the Hungarian journalist Desiderius Papp. The author claims that this book represents an innovation in astrobiological reasoning, as it draws on contemporary biological research to conduct thought experiments, thereby coming up with concrete forms of possible extraterrestrial life. One of the most interesting of these forms was crystalline life. After a short overview on the history of this concept, this article will show how Papp drew on recent research by Otto Lehmann on liquid crystals to convey the idea that life may be based on other elements than carbon. The author concludes by arguing that popular science did not only make specialist knowledge accessible to a general public but also served to probe the limits of knowledge and point toward the situatedness of established categories and definitions.

  18. Proceedings of the international workshop on reliability data collection in support of PSA, maintenance and life-assurance programmes

    International Nuclear Information System (INIS)

    1996-01-01

    The utilisation of data to support Probabilistic Safety Assessments, Maintenance Activities and Life-Assurance Programmes is becoming more widely recognized as these areas become more and more developed throughout the nuclear industry. Almost every member country of the OECD Nuclear Energy Agency uses PSA in one way or another in their assessment of nuclear power plant safety. A majority of utilities and licensees have completed or are in the process of planning plant specific PSAs. Operability costs associated with maintenance activities and life assurance programmes are highly dependent upon the data and how it is utilized. Considering these statements and the various suggestions made, the Workshop addressed the following topics concerning reliability data collection: data compilation systems; data bases development and management; data application; parameter estimation; common cause failure and dependent failure data

  19. Proceedings of the international workshop on reliability data collection in support of PSA, maintenance and life-assurance programmes

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-07-01

    The utilisation of data to support Probabilistic Safety Assessments, Maintenance Activities and Life-Assurance Programmes is becoming more widely recognized as these areas become more and more developed throughout the nuclear industry. Almost every member country of the OECD Nuclear Energy Agency uses PSA in one way or another in their assessment of nuclear power plant safety. A majority of utilities and licensees have completed or are in the process of planning plant specific PSAs. Operability costs associated with maintenance activities and life assurance programmes are highly dependent upon the data and how it is utilized. Considering these statements and the various suggestions made, the Workshop addressed the following topics concerning reliability data collection: data compilation systems; data bases development and management; data application; parameter estimation; common cause failure and dependent failure data

  20. Breastfeeding in the first hour of life and modern technology: prevalence and limiting factors

    OpenAIRE

    Maria Cristina Pillegi; Adriana Policastro; Sulim Abramovici; Eduardo Cordioli; Alice D’Agostini Deutsch

    2008-01-01

    Objective: To identify the prevalence and limiting factors ofbreastfeeding in the first hour of life at the Maternity Center of HospitalIsraelita Albert Einstein, where the predominant model of childbirthcare is largely based on the use of modern technology. Methods: Aretrospective study with quantitative analysis in a middle and upperclass population of different cultural backgrounds. Data were obtainedfrom the delivery record book in a total of 12,350 births from January2004 to December 200...

  1. Investing in Uncertainty: Young Adults with Life-Limiting Conditions Achieving Their Developmental Goals.

    Science.gov (United States)

    Cook, Karen A; Jack, Susan M; Siden, Hal; Thabane, Lehana; Browne, Gina

    2016-08-01

    With improvements in pediatric care and technology, more young adults (YAs) with life-limiting conditions (LLCs) are surviving into adulthood. However, they have limited expectations to live beyond the first decade of adulthood. This study describes the monumental efforts required for YAs with LLCs to achieve their goals in an abbreviated life. The experiences and aspirations of YAs with LLCs to achieve their goals are relatively unknown. This report focuses on their experiences of living with uncertainty and its impact on achieving developmental goals. This study is one component of a larger descriptive study using an innovative bulletin board focus group to examine life experiences of YAs with LLCs. YAs with LLCs share the aspirations and goals of all YAs. Some participants demonstrated a striking capacity to navigate system barriers and achieve their goals, whereas others "got stuck" resulting in lost opportunities. Successful personal life investments were possible if resources were made available, coordinated, navigable, and responsive to new and special requests. Transformative changes to health, social care, and community services are necessary to support their YA ambitions. This study gave voice to those who were previously unheard and demonstrates the monumental hurdles YAs with LLCs face to achieve their goals. A palliative approach to care can mitigate unnecessary hardships and support their goals.

  2. 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

  3. The reliability, validity and responsiveness of the Thai version of Systemic Lupus Erythematosus Quality of Life (SLEQOL-TH) instrument.

    Science.gov (United States)

    Kasitanon, N; Wangkaew, S; Puntana, S; Sukitawut, W; Leong, K P; Louthrenoo, W

    2013-03-01

    The English version of the Systemic Lupus Erythematosus Quality of Life Questionnaire (SLEQOL) is a validated disease-specific quality of life instrument. The aim of this study was to evaluate the psychometric properties of the Thai version of the SLEQOL (SLEQOL-TH). Two independent translators translated the SLEQOL into Thai. The back translation of this version was performed by two other independent translators. The final version, SLEQOL-TH, was completed after resolving the discrepancies revealed by the back translation. One hundred and nine patients with SLE were enrolled to test the reliability, construct validity, floor and ceiling effects, and sensitivity to the changes of the SLEQOL-TH at six months. The differential item functioning (DIF) between the Thai and English versions was analyzed using the partial gamma. The internal consistency of the SLEQOL-TH was satisfactory with the overall Cronbach's alpha of 0.86. The test-retest reliability of the SLEQOL-TH was acceptable with the intra-class correlation coefficient of 0.86. Low correlations between the SLEQOL-TH and SLEDAI were observed. The total score of the SLEQOL-TH was moderately responsive to changes in quality of life, with a standardized response mean of 0.50. When comparing the SLEQOL-TH from Thai SLE patients with the original SLEQOL version obtained from Singapore SLE patients, 11 out of 40 items showed a moderate to large DIF. The SLEQOL-TH has acceptable psychometric properties and shows construct validity. In comparison with the English version of SLEQOL, there are some items that showed DIF. The applicability of the SLEQOL-TH in real-life clinical practice and clinical trials needs to be determined.

  4. Quality of life for children with life-limiting and life-threatening illnesses: description and evaluation of a regional, collaborative model for pediatric palliative care.

    Science.gov (United States)

    Rogers, Susan K; Gomez, Carlos F; Carpenter, Philip; Farley, Jean; Holson, Debbie; Markowitz, Miriam; Rood, Brian; Smith, Karen; Nigra, Peter

    2011-05-01

    The care of children in the U.S. with life-limiting illnesses is inadequate. Misallocated resources, flawed assumptions and models of care, and a lack of appropriate professional education foster a costly, inefficient system that falls short of its true potential. This article details the evolution of a regional, shared approach to address these issues, the District of Columbia Pediatric Palliative Care Collaboration (DCPPCC), and includes its evolution, preliminary clinical results, and assessment of barriers encountered.

  5. Validity and reliability of a Nigerian-Yoruba version of the stroke-specific quality of life scale 2.0.

    Science.gov (United States)

    Odetunde, Marufat Oluyemisi; Akinpelu, Aderonke Omobonike; Odole, Adesola Christiana

    2017-10-19

    Psychometric evidence is necessary to establish scientific integrity and clinical usefulness of translations and cultural adaptations of the Stroke-Specific Quality of Life (SS-QoL) scale. However, the limited evidence on psychometrics of Yoruba version of SS-QoL 2.0 (SS-QoL(Y)) is a significant shortcoming. This study assessed the test-retest reliability, internal consistency, convergent, divergent, discriminant and known-group validity of the SS-QoL(Y). Yoruba version of the WHOQoL-BREF was used to test the convergent and divergent validity of the SS-QoL(Y) among 100 consenting stroke survivors. The WHOQoL-BREF and SS-QoL(Y) was administered randomly in order to eliminate bias. The test-retest reliability of the SS-QoL(Y) was carried out among 68 of the respondents within an interval of 7 days. All respondents were purposively recruited from selected secondary and tertiary health facilities in South-west Nigeria. Data were analysed using descriptive statistics of mean and standard deviation, and inferential statistics of Spearman correlation, Cronbach's alpha, Intra-class Correlation Coefficient (ICC), Independent t-test and One-way ANOVA. Alpha level was set at p validity of SS-QoL(Y) showed that items' r value ranged from 0.711 to 0.920 with their hypothesized domains. The scale demonstrated moderate to strong test-retest reliability with Intra-class correlation coefficient (ICC) for the domains and overall scores (r = 0.47 to 0.81) and moderate to high internal consistency (Cronbach's alpha =0.61 to 0.82) for domains scores. These correlations were also significant for the domains and overall scores (p validity, test-retest reliability and internal consistency of the Yoruba version of the Stroke Specific Quality of Life 2.0 are adequate while the convergent and divergent validity are low but acceptable. The SS-QoL(Y) is recommended for assessing health-related quality of life among Yoruba stroke survivors.

  6. Reliability residual-life prediction method for thermal aging based on performance degradation

    International Nuclear Information System (INIS)

    Ren Shuhong; Xue Fei; Yu Weiwei; Ti Wenxin; Liu Xiaotian

    2013-01-01

    The paper makes the study of the nuclear power plant main pipeline. The residual-life of the main pipeline that failed due to thermal aging has been studied by the use of performance degradation theory and Bayesian updating methods. Firstly, the thermal aging impact property degradation process of the main pipeline austenitic stainless steel has been analyzed by the accelerated thermal aging test data. Then, the thermal aging residual-life prediction model based on the impact property degradation data is built by Bayesian updating methods. Finally, these models are applied in practical situations. It is shown that the proposed methods are feasible and the prediction accuracy meets the needs of the project. Also, it provides a foundation for the scientific management of aging management of the main pipeline. (authors)

  7. Integrated Life-Cycle Framework for Maintenance, Monitoring and Reliability of Naval Ship Structures

    Science.gov (United States)

    2012-08-15

    uncertainty in quantitative risk and policy analysis, Cambridge Univer- sity Press. NEVES, L. C, FRANGOPOL, D. M., AND CRUZ , P. J. 2006 Probabilistic lifetime...L. C, FRANGOPOL, D. M., AND CRUZ , P. J. 2006 Probabilistic life- time-oriented multiobjective optimization of bridge maintenance: single...Wright Aeronautical Laboratory. Wright- Patterson Air Force Base, Dayton, Ohio; 1981. [5| Chung H-Y, Manuel L, Frank KH. Optimal inspection

  8. Integrated Life Cycle Management: A Strategy for Plants to Extend Operating Lifetimes Safely with High Operational Reliability

    International Nuclear Information System (INIS)

    Esselman, Thomas; Bruck, Paul; Mengers, Charles

    2012-01-01

    Nuclear plant operators are studying the possibility of extending their existing generating facilities operating lifetime to 60 years and beyond. Many nuclear plants have been granted licenses to operate their facilities beyond the original 40 year term; however, in order to optimize the long term operating strategies, plant decision-makers need a consistent approach to support their options. This paper proposes a standard methodology to support effective decision-making for the long-term management of selected station assets. Methods detailed are intended to be used by nuclear plant site management, equipment reliability personnel, long term planners, capital asset planners, license renewal staff, and others that intend to look at operation between the current time and the end of operation. This methodology, named Integrated Life Cycle Management (ILCM), will provide a technical basis to assist decision makers regarding the timing of large capital investments required to get to the end of operation safely and with high plant reliability. ILCM seeks to identify end of life cycle failure probabilities for individual plant large capital assets and attendant costs associated with their refurbishment or replacement. It will provide a standard basis for evaluation of replacement and refurbishment options for these components. ILCM will also develop methods to integrate the individual assets over the entire plant thus assisting nuclear plant decision-makers in their facility long term operating strategies. (author)

  9. Life management and operational experience feedback - tools to enhance safety and reliability of the NPP

    International Nuclear Information System (INIS)

    Mach, P.

    1997-01-01

    Preparation has started of the Temelin power plant centralized equipment database. Principles of reliability centered maintenance are studied, and use of these activities will be made in the Plant Ageing Management Programme. The aims of the Programme are as follows: selection of important components subject to ageing, data collection, determination of dominant stressors, development, selection and validation of ageing evaluation methods, setup of experience feedback, determination of responsibilities, methodologies and strategy, elaboration of programme procedures and documentation, and maintenance of programme flexibility. Pilot studies of component ageing are under way: for the reactor pressure vessel, steam generator, pressurizer, piping, ECCS and cables. The organizational structure of the Operational Experience Feedback system is described, as are the responsibility of staff and sources of information. (M.D.)

  10. The real limits to marine life: a further critique of the Respiration Index

    Science.gov (United States)

    Seibel, B. A.; Childress, J. J.

    2013-05-01

    The recently proposed "Respiration Index" (RI = log PO2/PCO2) suggests that aerobic metabolism is limited by the ratio of reactants (oxygen) to products (carbon dioxide) according to the thermodynamics of cellular respiration. Here, we demonstrate further that, because of the large standard free energy change for organic carbon oxidation (ΔG° = -686 kcal mol-1), carbon dioxide can never reach concentrations that would limit the thermodynamics of this reaction. A PCO2 to PO2 ratio of 10503 would be required to reach equilibrium (equilibrium constant, Keq = 10503), where ΔG = 0. Thus, a Respiration Index of -503 would be the real thermodynamic limit to aerobic life. Such a Respiration Index is never reached, either in the cell or in the environment. Moreover, cellular respiration and oxygen provision are kinetically controlled such that, within limits, environmental oxygen and CO2 concentrations have little to do with intracellular concentrations. The RI is fundamentally different from the aragonite saturation state, a thermodynamic index used to quantify the potential effect of CO2 on calcification rates, because of its failure to incorporate the equilibrium constant of the reaction. Not only is the RI invalid, but its use leads to incorrect and misleading predictions of the threat of changing oxygen and carbon dioxide to marine life. We provide a physiological framework that identifies oxygen thresholds and allows for synergistic effects of ocean acidification and global warming.

  11. The real limits to marine life: a further critique of the Respiration Index

    Directory of Open Access Journals (Sweden)

    B. A. Seibel

    2013-05-01

    Full Text Available The recently proposed "Respiration Index" (RI = log PO2/PCO2 suggests that aerobic metabolism is limited by the ratio of reactants (oxygen to products (carbon dioxide according to the thermodynamics of cellular respiration. Here, we demonstrate further that, because of the large standard free energy change for organic carbon oxidation (ΔG° = −686 kcal mol−1, carbon dioxide can never reach concentrations that would limit the thermodynamics of this reaction. A PCO2 to PO2 ratio of 10503 would be required to reach equilibrium (equilibrium constant, Keq = 10503, where ΔG = 0. Thus, a Respiration Index of −503 would be the real thermodynamic limit to aerobic life. Such a Respiration Index is never reached, either in the cell or in the environment. Moreover, cellular respiration and oxygen provision are kinetically controlled such that, within limits, environmental oxygen and CO2 concentrations have little to do with intracellular concentrations. The RI is fundamentally different from the aragonite saturation state, a thermodynamic index used to quantify the potential effect of CO2 on calcification rates, because of its failure to incorporate the equilibrium constant of the reaction. Not only is the RI invalid, but its use leads to incorrect and misleading predictions of the threat of changing oxygen and carbon dioxide to marine life. We provide a physiological framework that identifies oxygen thresholds and allows for synergistic effects of ocean acidification and global warming.

  12. The reliability and validity of the short version of the WHO Quality of Life Instrument in an Arab general population

    International Nuclear Information System (INIS)

    Ohaeri, Jude U; Awadallab, Abdel W

    2009-01-01

    There is rising interest in quality of life (QOL) research in Arabian countries. The aim of this study was to assess in a nationwide sample of Kuwaiti subjects the reliability and validity of the World Health Organization Quality of Life (WHOQOL-BREF), a shorter version of the widely used QOL assessment instrument that comprises 26 items in the domains of physical health, psychological health, social relationships, and the environment. A one-in-three systematic random proportionate sample of consenting Kuwaiti nationals attending large cooperative stores and municipal government offices in the six governorates completed the Arabic translation of the questionnaire. The indices assessed included test-retest reliability, internal consistency, item internal consistency (2C), item discriminant validity (IDV), known-groups and construct validity. There were 3303 participants (44.8% males, 55.2% females, mean age 35.4 years, range 16 to 87 years). The intra-class correlation for the test-retest statistic and the internal consistency values for the full questionnaire and the domains had a Cronbach's alpha > - 0.7. Of the 24 items that constitute the domains, 21 met the 2 C requirement of correlation > - 0.4 with the corresponding domain, while 16 met the IDV criterion of having a higher correlation with their corresponding domain than other domains. Domain scores discriminated significantly between well and sick groups. In the factor analysis, four strong factors emerged with the same construct as in the WHO report. The Arabic translation of the WHOQOL-BREF has impressive reliability and validity indices. The poor IDV findings are due to the multidimensional nature of the questionnaire. The highly significant validity indices should reassure researchers that the questionnaire represents the same constructs across cultures. Negatively worded items possibly need refinement. (author)

  13. Validity and reliability of the Dutch adaptation of the Psoriatic Arthritis Quality of Life (PsAQoL Questionnaire.

    Directory of Open Access Journals (Sweden)

    Freke Wink

    Full Text Available OBJECTIVE: The Psoriatic Arthritis Quality of Life (PsAQoL questionnaire is a disease- specific instrument developed to measure quality of life (QoL in patients with psoriatic arthritis (PsA. The aim of this study was to translate the measure into Dutch and to determine its psychometric properties. METHOD: Translation of the original English PsAQoL into Dutch was performed by bilingual and lay panel. Ten field-test interviews with PsA patients were performed to assess face and content validity. In total, 211 PsA patients were included in a test-retest postal survey to investigate the reliability and construct validity of the Dutch adaptation of the PsAQoL. The PsAQoL, Health Assessment Questionnaire (HAQ and Skindex-17 were administered on two different occasions approximately two weeks apart. RESULTS: The Dutch version of the PsAQoL was found to be relevant, understandable and easy to complete in only a few minutes. It correlated as expected with the HAQ (Spearman's ρ = 0.72 and the 2 subscales of the Skindex-17 (ρ = 0.40 for the psychosocial and ρ = 0.46 for the symptom scale. Furthermore, the measure had good internal consistency (Cronbach's α = 0.92 and test-retest reliability (ρ = 0.89. The PsAQoL was able to define groups of patients based on self-reported general health status, self-reported severity of PsA and flare of arthritis. Duration of PsA did not influence PsAQoL scores. CONCLUSIONS: The Dutch version of the PsAQoL is a valid and reliable questionnaire suitable for use in clinical or research settings to asses PsA-specific QoL.

  14. General Method of Using Bayesian Nets for a Software Reliability Assessment in Varying SW Development Life cycle

    International Nuclear Information System (INIS)

    Eom, Heung Seop; Chang, Seung Cheol

    2008-01-01

    Bayesian Net (BN) has been used in many researches to predict software defects, because it allows all the evidence to be taken into account. However one of the serious difficulties in the earlier works was that the user had to build a different BN for each software development life cycle. This limits the practical use of BN in the field. One way to solve this problem is the use of general BN templates which are not restricted to a particular software life cycle. This paper describes a method for this purpose on the strength of Object- Oriented BN (OOBN) and Dynamic BN (DBN) technique

  15. Equipment reliability and life cycle optimization of a nuclear plant feedwater heater

    International Nuclear Information System (INIS)

    Thomas, Daniel; Coakley, Michael; Catapano, Michael; Svensson, Eric

    2006-01-01

    Many papers published over the last 25 years have strongly emphasized the need for an ongoing program of inspection and testing with subsequent failure cause analysis of feedwater heaters. Plants must be run more competitively; therefore, Utilities must lower operation and maintenance costs, while optimizing overall plant efficiency and capacity factor. One recognized area that needs to be addressed in accomplishing this goal is the heat cycle. This paper specifically deals with the feedwater heating system. Utility engineers must monitor feedwater heater performance in order to recognize degradation, identify and mitigate failure mechanisms, and prevent in-service failures thereby optimizing availability. Periodic tube plugging without complete analysis of the degraded/failed areas resolves the immediate need for return to service; however, heater life will not be optimized. This paper illustrates a complete life cycle management inspection, testing, and maintenance program implemented at Peach Bottom Atomic Power Station (PBAPS). Concerns that tubes may have been too conservatively plugged due to insufficient data and lack of root cause analysis, justified a program that included: - Removal of previously installed plugs; - Video-probe inspection of failed areas; - Extraction of tube samples for further analysis; - Eddy current testing of selected tubes; - Evaluation of the condition of 'insurance' plugged tubes for return to service; - Hydrostatic testing of selected individual tubes; - Final repair plan based on the results of the above program. This paper concludes that no single method of inspection or testing should solely be relied upon in establishing: - The extent of actual degraded conditions; - The mechanism(s) of failure; - The details of repair to be implemented. Evaluating all data affords the best chance in arresting problems and optimizing feedwater heater life. Problem heaters should be continuously monitored and inspected over time until the facts

  16. Validity and reliability of the Korean version of the pediatric quality of life ESRD module

    Directory of Open Access Journals (Sweden)

    Park Ki-Soo

    2012-06-01

    Full Text Available Abstract Background Health-related quality of life is a very important issue in children with end-stage renal disease and their family. Moreover, this can be a lifelong problem. In this study, we performed a cross-sectional investigation of the health-related quality of life in Korean children, undergoing renal replacement therapies, such as dialysis and renal transplantation. Findings We validated the Korean version of the PedsQL 3.0 End-Stage Renal Disease Module by comparing with the PedsQL 4.0 Generic Core Scales. A total of 92 pediatric patients with end-stage renal disease, aged 2–18 year old, were enrolled in four teaching hospitals in Korea. The module was acceptable for both parent proxy-report and child self-report. The response rate was acceptable, since no reminders were delivered. A large proportion of the responders answered >90% of the items, which suggests a good face validity. The PedsQL 4.0 Generic Core Scales and the PedsQL 3.0 End-Stage Renal Disease Module showed minimal missing values in the current study, which supported feasibility. The validation analyses revealed acceptable floor and ceiling effects and an acceptable construct validity. Conclusions The PedsQL 3.0 End-stage Renal Disease Module may be useful as an end-stage renal disease -specific instrument in the evaluation of the health-related quality of life in Korean children; however, a larger, longitudinal prospective study is needed.

  17. 49 CFR Appendix B to Part 564 - Information To Be Submitted for Long Life Replaceable Light Sources of Limited Definition

    Science.gov (United States)

    2010-10-01

    ...—Information To Be Submitted for Long Life Replaceable Light Sources of Limited Definition I. Filament or... Source that Operates With a Ballast and Rated Life of the Light Source/Ballast Combination. A. Maximum power (in watts). B. Luminous Flux (in lumens). C. Rated laboratory life of the light source/ballast...

  18. 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.

  19. Breastfeeding in the first hour of life and modern technology: prevalence and limiting factors

    Directory of Open Access Journals (Sweden)

    Maria Cristina Pillegi

    2008-12-01

    Full Text Available Objective: To identify the prevalence and limiting factors ofbreastfeeding in the first hour of life at the Maternity Center of HospitalIsraelita Albert Einstein, where the predominant model of childbirthcare is largely based on the use of modern technology. Methods: Aretrospective study with quantitative analysis in a middle and upperclass population of different cultural backgrounds. Data were obtainedfrom the delivery record book in a total of 12,350 births from January2004 to December 2007. Results: Of 12,350 births, 3,277 (26.9%were excluded because of contraindications to breastfeeding in thefirst hour of life such as: prematurity, respiratory distress, adverseeffects of anesthesia, obstetric conditions, congenital malformation,and others. Other 180 cases were excluded due to missing data.Of the remaining 8,893 cases, 2,279 (18.7% were not breastfedbecause of limiting factors that require improvement actions: highdelivery turnover, patient refusal, medical refusal, tiredness due toprolonged labor, loss of data recording. Cesarean delivery and the useof anesthesia did neither prevent breastfeeding in the first hour of lifenor skin-to-skin contact. The prevalence was 74.3%. Conclusions:The use of technology and the hospital practices interfere inbreastfeeding, but are not factors that prevent it. The identificationof the prevalence and limiting factors contributes to the evaluationof the care provided and elaboration of nursing interventions forcontinuous improvement of the care practice. Improvement actionsshould include prenatal care and delivery itself.

  20. Stochastic Dynamic Programming for Three-Echelon Inventory System of Limited Shelf Life Products

    Directory of Open Access Journals (Sweden)

    Galal Noha M.

    2016-01-01

    Full Text Available Coordination of inventory decisions within the supply chain is one of the major determinants of its competitiveness in the global market. Products with limited shelf life impose additional challenges in managing the inventory across the supply chain because of the additional wastage costs incurred in case of being stored beyond product’s useful life. This paper presents a stochastic dynamic programming model for inventory replenishment in a serial multi-echelon distribution supply chain. The model considers uncertain stationary discrete demand at the retailer and zero lead time. The objective is to minimize expected total costs across the supply chain echelons, while maintaining a preset service level. The results illustrate that a cost saving of around 17% is achievable due to coordinating inventory decisions across the supply chain.

  1. Description of Anomalous Noise Events for Reliable Dynamic Traffic Noise Mapping in Real-Life Urban and Suburban Soundscapes

    Directory of Open Access Journals (Sweden)

    Francesc Alías

    2017-02-01

    Full Text Available Traffic noise is one of the main pollutants in urban and suburban areas. European authorities have driven several initiatives to study, prevent and reduce the effects of exposure of population to traffic. Recent technological advances have allowed the dynamic computation of noise levels by means of Wireless Acoustic Sensor Networks (WASN such as that developed within the European LIFE DYNAMAP project. Those WASN should be capable of detecting and discarding non-desired sound sources from road traffic noise, denoted as anomalous noise events (ANE, in order to generate reliable noise level maps. Due to the local, occasional and diverse nature of ANE, some works have opted to artificially build ANE databases at the cost of misrepresentation. This work presents the production and analysis of a real-life environmental audio database in two urban and suburban areas specifically conceived for anomalous noise events’ collection. A total of 9 h 8 min of labelled audio data is obtained differentiating among road traffic noise, background city noise and ANE. After delimiting their boundaries manually, the acoustic salience of the ANE samples is automatically computed as a contextual signal-to-noise ratio (SNR. The analysis of the real-life environmental database shows high diversity of ANEs in terms of occurrences, durations and SNRs, as well as confirming both the expected differences between the urban and suburban soundscapes in terms of occurrences and SNRs, and the rare nature of ANE.

  2. 24. MPA-seminar: safety and reliability of plant technology with special emphasis on integrity and life management. Vol. 2. Papers 28-63

    International Nuclear Information System (INIS)

    1999-01-01

    The second volume is dedicated to the safety and reliability of plant technology with special emphasis on the integrity and life management. The following topics are discussed: 1. Integrity of vessels, pipes and components. 2. Fracture mechanics. 3. Measures for the extension of service life, and 4. Online Monitoring. All 30 contributions are separately analyzed for this database. (orig.)

  3. Bayesian analysis of heat pipe life test data for reliability demonstration testing

    International Nuclear Information System (INIS)

    Bartholomew, R.J.; Martz, H.F.

    1985-01-01

    The demonstration testing duration requirements to establish a quantitative measure of assurance of expected lifetime for heat pipes was determined. The heat pipes are candidate devices for transporting heat generated in a nuclear reactor core to thermoelectric converters for use as a space-based electric power plant. A Bayesian analysis technique is employed, utilizing a limited Delphi survey, and a geometric mean accelerated test criterion involving heat pipe power (P) and temperature (T). Resulting calculations indicate considerable test savings can be achieved by employing the method, but development testing to determine heat pipe failure mechanisms should not be circumvented

  4. Differences on psychosocial outcomes between male and female caregivers of children with life-limiting illnesses.

    Science.gov (United States)

    Schneider, Monica; Steele, Rose; Cadell, Susan; Hemsworth, David

    2011-06-01

    This secondary analysis of data examined the psychosocial outcomes of meaning in caregiving, self-esteem, optimism, burden, depression, spirituality, and posttraumatic growth in 273 parents caring for children with life-limiting illnesses to (a) determine if there were gender differences and (b) identify gender-specific correlations among these outcomes. Findings suggest that significant gender differences exist. Women reported higher average scores compared with men for meaning in caregiving, depression, burden, and posttraumatic growth and lower average scores for optimism. Correlations also revealed some significant differences. Health care professionals need to be aware of gender differences and tailor their interventions appropriately. Copyright © 2011 Elsevier Inc. All rights reserved.

  5. First 0ν half-life limit from the Gotthard xenon time projection chamber

    International Nuclear Information System (INIS)

    Wong, H.T.; Boehm, F.; Fisher, P.

    1991-01-01

    A xenon Time Projection Chamber with an active volume of 207 liters has been built to study 0ν and 2ν double beta decay in 136 Xe. The TPC has been installed in the Gotthard Tunnel Underground Laboratory, and is currently taking data with 5 atm of xenon enriched in 62.5% 136 Xe. The first 166 hours of data are presented. Based on this data set, we deduce a half-life limit of T(0 + → 0 + ) > 6.2 x 10 21 years for the 0ν mode, at a 90% C.L. (author)

  6. Cold aqueous planetary geochemistry with FREZCHEM from modeling to the search for life at the limits

    CERN Document Server

    Marion, Giles M

    2007-01-01

    This book explicitly investigates issues of astrobiological relevance in the context of cold aqueous planetary geochemistry. At the core of the technical chapters is the FREZCHEM model, initially developed over many years by one of the authors to quantify aqueous electrolyte properties and chemical thermodynamics at subzero temperatures. FREZCHEM, of general relevance to biogeochemists and geochemical modelers, cold planetary scientists, physicochemists and chemical engineers, is subsequently applied to the exploration of biogeochemical applications to solar systems bodies in general, and to speculations about the limits for life in cold environments in particular.

  7. Life Cycle Management for Equipments in Nuclear Plants Based on Reliability

    International Nuclear Information System (INIS)

    Wang Dalin; Sun Jinlong

    2012-01-01

    Majority of equipments in nuclear power stations are not un-repairable, but repaired after failures or maintained periodically and then returned to running. Along with aging or fatigue causes, duration between failures may be variable such as larger or shorter. Equipments failure occurrences are consistent with non-homogeneous Poisson process (NHPP), in which their failure rates are variable. We chose Weibull process to simplify the actual circumstances to obtain the optimal life cycle management plans approximately. In application we need to estimate parameters of Weibull process with existing data. Before that, trend test is necessary. Total time test (TTT) is an alternative. Trend test can determine whether the failure rate changes along operating time and whether the devices operated under imperfect or minimal repair. Parameters of Weibull process λ, β can be estimated by maximum likelihood estimation method. LCM model is designed to found an optimizing model for those aging equipments under minimal repair or imperfect maintenance with maximum economic or availability as objective function. The purpose is to establish the optimal replacement strategies. Periodical replacement is the most regular choice and so LCM model aims to calculate the optimal replacement periodical duration.

  8. Real-life decision making in college students. II: Do individual differences show reliable effects?

    Science.gov (United States)

    Galotti, Kathleen M; Tandler, Jane M; Wiener, Hillary J D

    2014-01-01

    First-year undergraduates participated in a short-term longitudinal study of real-life decision making over their first 14 months of college. They were surveyed about 7 different decisions: choosing courses for upcoming terms (on 3 different occasions), choosing an academic major (twice), planning for the upcoming summer, and planning for sophomore-year housing. They also completed a survey of self-reported decision-making styles and the Need for Cognition survey (Cacioppo & Petty, 1982) to assess their focus on rationality and enjoyment of analytic thinking. Results showed few statistically significant correlations between stylistic measures and behavioral measures of decision making, in either the amount of information considered or the way in which the information integration tracked predictions of linear models of decision making applied to each participant's data. However, there were consistent correlations, across the 7 decisions, between stylistic measures and affective reactions to, or retrospective descriptions of, episodes of decision making. We suggest that decision-making styles instruments may better reflect the construction of narratives of self as a decision maker more than they do actual behavior during decision making.

  9. Measuring the reliability and validity of the Greek edition of the Diabetes Quality of Life Brief Clinical Inventory.

    Science.gov (United States)

    Rekleiti, Maria; Souliotis, Kyriakos; Sarafis, Pavlos; Kyriazis, Ioannis; Tsironi, Maria

    2018-06-01

    The present study focuses on studying the validity and reliability of the Greek edition of DQOL-BCI. DQOL-BCI includes 15 questions-elements that are evaluated on a 5-grade scale like Likert and two general form-shapes. The translation process was conducted in conformity with the guidelines of EuroQol group. A non-random sample of 65 people-patients diagnosed with diabetes I and II was selected. The questionnaire that was used to collect the data was the translated version of DQOL-BCI, and included the demographic characteristics of the interviewees. The content validity of DQOL-BCI was re-examined from a team of five experts (expert panel) for qualitative and quantitative performance. The completion of the questionnaire was done via a personal interview. The sample consisted of 58 people (35 men and 23 women, 59.9 ± 10.9 years). The translation of the questionnaire was found appropriate in accordance to the peculiarities of the Greek language and culture. The largest deviation of values is observed in QOL1 (1.71) in comparison to QOL6 (2.98). The difference between the standard deviations is close to 0.6. The statistics results of the tests showed satisfactory content validity and high construct validity, while the high values for Cronbach alpha index (0.95) reveal high reliability and internal consistency. The Greek version of DQOL-BCI has acceptable psychometric properties and appears to demonstrate high internal reliability and satisfactory construct validity, which allows its use as an important tool in evaluating the quality of life of diabetic patients in relation to their health. Copyright © 2018. Published by Elsevier B.V.

  10. Maintenance, reliability and policies for orbital space station life support systems

    International Nuclear Information System (INIS)

    Russell, James F.; Klaus, David M.

    2007-01-01

    The performance of productive work on space missions is critical to sustaining a human presence on orbital space stations (OSS), the Moon, or Mars. Available time for productive work has potentially been impacted on past OSS missions by underestimating the crew time needed to maintain systems, such as the Environmental Control and Life Support System (ECLSS). To determine the cause of this apparent disconnect between the design and operation of an OSS, documented crew time for maintenance was collected from the three Skylab missions and Increments 4-8 on the International Space Station (ISS), and the data was contrasted to terrestrial facility maintenance norms. The results of the ISS analysis showed that for four operational and seven functional categories, the largest deviation of 60.4% over the design time was caused by three of the four operational categories not being quantitatively included in the design documents. In a cross category analysis, 35.3% of the crew time was found to have been used to repair air and waste handling systems. The air system required additional crew time for maintenance due to a greater than expected failure rate and resultant increased time needed for repairs. Therefore, it appears that the disconnect between the design time and actual operations for ECLSS maintenance on ISS was caused by excluding non-repair activities from the estimates and experiencing greater than expected technology maintenance requirements. Based on these ISS and Skylab analyses, future OSS designs (and possibly lunar and Martian missions as well) should consider 3.0-3.3 h/day for crews of 2 to 3 as a baseline of crew time needed for ECLSS maintenance

  11. Self-reported quality of life measure is reliable and valid in adult patients suffering from schizophrenia with executive impairment.

    Science.gov (United States)

    Baumstarck, Karine; Boyer, Laurent; Boucekine, Mohamed; Aghababian, Valérie; Parola, Nathalie; Lançon, Christophe; Auquier, Pascal

    2013-06-01

    Impaired executive functions are among the most widely observed in patients suffering from schizophrenia. The use of self-reported outcomes for evaluating treatment and managing care of these patients has been questioned. The aim of this study was to provide new evidence about the suitability of self-reported outcome for use in this specific population by exploring the internal structure, reliability and external validity of a specific quality of life (QoL) instrument, the Schizophrenia Quality of Life questionnaire (SQoL18). cross-sectional study. age over 18 years, diagnosis of schizophrenia according to the DSM-IV criteria. sociodemographic (age, gender, and education level) and clinical data (duration of illness, Positive and Negative Syndrome Scale, Calgary Depression Scale for Schizophrenia); QoL (SQoL18); and executive performance (Stroop test, lexical and verbal fluency, and trail-making test). Non-impaired and impaired populations were defined for each of the three tests. For the six groups, psychometric properties were compared to those reported from the reference population assessed in the validation study. One hundred and thirteen consecutive patients were enrolled. The factor analysis performed in the impaired groups showed that the questionnaire structure adequately matched the initial structure of the SQoL18. The unidimensionality of the dimensions was preserved, and the internal/external validity indices were close to those of the non-impaired groups and the reference population. Our study suggests that executive dysfunction did not compromise the reliability or validity of self-reported disease-specific QoL questionnaire. Copyright © 2013 Elsevier B.V. All rights reserved.

  12. Assessing software quality at each step of its life-cycle to enhance reliability of control systems

    International Nuclear Information System (INIS)

    Hardion, V.; Buteau, A.; Leclercq, N.; Abeille, G.; Pierre-Joseph, Z.; Le, S.

    2012-01-01

    A distributed software control system aims to enhance the upgrade ability and reliability by sharing responsibility between several components. The disadvantage is that it makes it harder to detect problems on a significant number of modules. With Kaizen in mind we have chosen to continuously invest in automation to obtain a complete overview of software quality despite the growth of legacy code. The development process has already been mastered by staging each life-cycle step thanks to a continuous integration server based on JENKINS and MAVEN. We enhanced this process, focusing on 3 objectives: Automatic Test, Static Code Analysis and Post-Mortem Supervision. Now, the build process automatically includes a test section to detect regressions, incorrect behaviour and integration incompatibility. The in-house TANGOUNIT project satisfies the difficulties of testing distributed components such as Tango Devices. In the next step, the programming code has to pass a complete code quality check-up. The SONAR quality server has been integrated in the process, to collect each static code analysis and display the hot topics on summary web pages. Finally, the integration of Google BREAKPAD in every TANGO Devices gives us essential statistics from crash reports and enables us to replay the crash scenarios at any time. We have already gained greater visibility on current developments. Some concrete results will be presented including reliability enhancement, better management of subcontracted software development, quicker adoption of coding standards by new developers and understanding of impacts when moving to a new technology. (authors)

  13. Siblings of children with life-limiting conditions: psychological adjustment and sibling relationships.

    Science.gov (United States)

    Fullerton, J M; Totsika, V; Hain, R; Hastings, R P

    2017-05-01

    This study explored psychological adjustment and sibling relationships of siblings of children with life-limiting conditions (LLCs), expanding on previous research by defining LLCs using a systematic classification of these conditions. Thirty-nine siblings participated, aged 3-16 years. Parents completed measures of siblings' emotional and behavioural difficulties, quality of life, sibling relationships and impact on families and siblings. Sibling and family adjustment and relationships were compared with population norms, where available, and to a matched comparison group of siblings of children with autistic spectrum disorder (ASD), as a comparable 'high risk' group. LLC siblings presented significantly higher levels of emotional and behavioural difficulties, and lower quality of life than population norms. Their difficulties were at levels comparable to siblings of children with ASD. A wider impact on the family was confirmed. Family socio-economic position, time since diagnosis, employment and accessing hospice care were factors associated with better psychological adjustment. Using a systematic classification of LLCs, the study supported earlier findings of increased levels of psychological difficulties in siblings of children with a LLC. The evidence is (i) highlighting the need to provide support to these siblings and their families, and (ii) that intervention approaches could be drawn from the ASD field. © 2016 John Wiley & Sons Ltd.

  14. Mathematical model of the competition life cycle under limited resources conditions: Problem statement for business community

    Science.gov (United States)

    Shelomentsev, A. G.; Medvedev, M. A.; Berg, D. B.; Lapshina, S. N.; Taubayev, A. A.; Davletbaev, R. H.; Savina, D. V.

    2017-12-01

    Present study is devoted to the development of competition life cycle mathematical model in the closed business community with limited resources. Growth of each agent is determined by the balance of input and output resource flows: input (cash) flow W is covering the variable V and constant C costs and growth dA/dt of the agent's assets A. Value of V is proportional to assets A that allows us to write down a first order non-stationary differential equation of the agent growth. Model includes the number of such equations due to the number of agents. The amount of resources that is available for agents vary in time. The balances of their input and output flows are changing correspondingly to the different stages of the competition life cycle. According to the theory of systems, the most complete description of any object or process is the model of its life cycle. Such a model describes all stages of its development: from the appearance ("birth") through development ("growth") to extinction ("death"). The model of the evolution of an individual firm, not contradicting the economic meaning of events actually observed in the market, is the desired result from modern AVMs for applied use. With a correct description of the market, rules for participants' actions, restrictions, forecasts can be obtained, which modern mathematics and the economy can not give.

  15. Survey of neonatologists' attitudes toward limiting life-sustaining treatments in the neonatal intensive care unit.

    Science.gov (United States)

    Feltman, D M; Du, H; Leuthner, S R

    2012-11-01

    To understand neonatologists' attitudes toward end-of-life (EOL) management in clinical scenarios, EOL ethical concepts and resource utilization. American Academy of Pediatrics (AAP) Perinatal section members completed an anonymous online survey. Respondents indicated preferences in limiting life-sustaining treatments in four clinical scenarios, ranked agreement with EOL-care ethics statements, indicated outside resources previously used and provided demographic information. In all, 451 surveys were analyzed. Across clinical scenarios and as general ethical concepts, withdrawal of mechanical ventilation in severely affected patients was most accepted by respondents; withdrawal of artificial nutrition and hydration was least accepted. One-third of neonatologists did not agree that non-initiation of treatment is ethically equivalent to withdrawal. Around 20% of neonatologists would not defer care if uncomfortable with a parent's request. Respondents' resources included ethics committees, AAP guidelines and legal counsel/courts. Challenges to providing just, unified EOL care strategies are discussed, including deferring care, limiting artificial nutrition/hydration and conditions surrounding ventilator withdrawal.

  16. Fathers' experiences of their child's life-limiting condition: An attachment narrative perspective.

    Science.gov (United States)

    Bailey-Pearce, Oliver; Stedmon, Jacqui; Dallos, Rudi; Davis, George

    2017-09-01

    When a child has a life-limiting illness, parental involvement is amplified, having to respond to the increased needs of the child. Both parents are affected by the illness, yet research has largely under-represented fathers' experiences of their child's illness. Seven fathers were interviewed about their experiences with their child's life-limiting illness. In addition, fathers' attachment strategies were assessed using the Adult Attachment Interview. Narrative analysis was implemented to explore the interviews, and indicators of attachment markers employed in the Adult Attachment Interview were also identified. The dominant themes were found to be 'experience of the diagnosis', 'living with the illness', 'struggling with emotions' and 'relationship with staff'. Within each theme, there were differences which related to the father's attachment strategies. This was particularly evident in parts of their narratives recounting critical moments of threat and anxiety in the course of discovering and adjusting to their child's illness. Importantly, the findings also suggested that the experience for the fathers stressed, and in some cases disrupted, their attachment coping strategies. All fathers told stories of trying to get it right for their children and family. Their experiences of, and adjustment to, the illness were related to their attachment strategies. The clinical implications for health professionals are discussed.

  17. Meaning and Practice of Palliative Care for Hospitalized Older Adults with Life Limiting Illnesses

    Directory of Open Access Journals (Sweden)

    Bethel Ann Powers

    2011-01-01

    Full Text Available Objective. To illustrate distinctions and intersections of palliative care (PC and end-of-life (EOL services through examples from case-centered data of older adults cared for during a four-year ethnographic study of an acute care hospital palliative care consultation service. Methods. Qualitative narrative and thematic analysis. Results. Description of four practice paradigms (EOL transitions, prognostic uncertainty, discharge planning, and patient/family values and preferences and identification of the underlying structure and communication patterns of PC consultation services common to them. Conclusions. Consistent with reports by other researchers, study data support the need to move beyond equating PC with hospice or EOL care and the notion that EOL is a well-demarcated period of time before death. If professional health care providers assume that PC services are limited to assisting with and helping patients and families prepare for dying, they miss opportunities to provide care considered important to older individuals confronting life-limiting illnesses.

  18. The Importance of Awareness and Communication for the Inclusion of Young People with Life-Limiting and Life-Threatening Conditions in Mainstream Schools and Colleges

    Science.gov (United States)

    Asprey, Anthea; Nash, Tricia

    2006-01-01

    Anthea Asprey and Tricia Nash both belong to the Children's Hospice South West Research Group, based at the University of Exeter. In this article, they report one aspect of a research project designed to determine the adequacy of support for young people with life-limiting and life-threatening conditions in the education system. They describe here…

  19. Reliable micro-measurement of strontium is the key to cracking the life-history code in the fish otolith

    International Nuclear Information System (INIS)

    Markwitz, A.; Grambole, D.; Herrmann, F.; Trompetter, W.J.; Dioses, T.; Gauldie, R.W.

    2000-01-01

    The fish otolith is a calcium carbonate (usually aragonite) crystal that grows continuously by accretion over the life of the fish and unlike bone is not continuously re-metabolised. Consequently, the otolith has long been regarded as a potential store of information about the life history of an individual fish, and this information is encoded in the deposition pattern of trace elements in the otolith. The code has been difficult to crack. However, recent developments have show that: (1) Sr is one of the few non-mobile trace elements in the otolith; and (2) the pattern of Sr deposition summarises the effects of environment changes that affect the growth rate of the otolith crystal. The remaining difficulties in cracking the chemical code in the otolith have hinged about making reliable micro-measurements of the stable Sr content at spatial resolutions of 10 μm or less; this interval represents about 4-6 days of otolith growth in most species of fish. This paper describes high beam resolution 2 μm linear measurements, and 6 μm square measurements over narrow windows of about 300 μm square, and links these micro-measures to macro-measures of 2D maps of the entire surface of sections of otoliths up to 5 mm square at beam resolutions of 25 μm square. The otoliths used in this study are from the Jurel, or Peruvian Jack mackerel, Trachurus murphyi (Carangidae: Teleostei)

  20. New Empirical Evidence on the Validity and the Reliability of the Early Life Stress Questionnaire in a Polish Sample.

    Science.gov (United States)

    Sokołowski, Andrzej; Dragan, Wojciech Ł

    2017-01-01

    Background: The Early Life Stress Questionnaire (ELSQ) is widely used to estimate the prevalence of negative events during childhood, including emotional, physical, verbal, sexual abuse, negligence, severe conflicts, separation, parental divorce, substance abuse, poverty, and so forth. Objective: This study presents the psychometric properties of the Polish adaptation of the ELSQ. It also verifies if early life stress (ELS) is a good predictor of psychopathology symptoms during adulthood. Materials and Methods: We analyzed data from two samples. Sample 1 was selected by random quota method from across the country and included 609 participants aged 18-50 years, 306 women (50.2%) and 303 men (49.8%). Sample 2 contained 503 young adults (253 women and 250 men) aged 18-25. Confirmatory and exploratory factor analyses were used to measure ELSQ internal consistency. The validity was based on the relation to psychopathological symptoms and substance misuse. Results: Results showed good internal consistency and validity. Exploratory factor analysis indicates a six-factor structure of the ELSQ. ELS was related to psychopathology in adulthood, including depressive, sociophobic, vegetative as well as pain symptoms. ELSQ score correlated also with alcohol use, but not nicotine dependence. Moreover, ELS was correlated with stress in adulthood. Conclusion: The findings indicate that the Polish version of the ELSQ is a valid and reliable instrument for assessing ELS in the Polish population and may be applied in both clinical and community samples.

  1. Reliability Analysis of Wind Turbines

    DEFF Research Database (Denmark)

    Toft, Henrik Stensgaard; Sørensen, John Dalsgaard

    2008-01-01

    In order to minimise the total expected life-cycle costs of a wind turbine it is important to estimate the reliability level for all components in the wind turbine. This paper deals with reliability analysis for the tower and blades of onshore wind turbines placed in a wind farm. The limit states...... consideres are in the ultimate limit state (ULS) extreme conditions in the standstill position and extreme conditions during operating. For wind turbines, where the magnitude of the loads is influenced by the control system, the ultimate limit state can occur in both cases. In the fatigue limit state (FLS......) the reliability level for a wind turbine placed in a wind farm is considered, and wake effects from neighbouring wind turbines is taken into account. An illustrative example with calculation of the reliability for mudline bending of the tower is considered. In the example the design is determined according...

  2. International Children's Palliative Care Network: A Global Action Network for Children With Life-Limiting Conditions.

    Science.gov (United States)

    Marston, Joan; Boucher, Sue; Downing, Julia

    2018-02-01

    The International Children's Palliative Care Network (ICPCN) is a global network of individuals and organizations working together to reach the estimated 21 million children with life-limiting conditions and life-threatening illnesses. The drive to establish the ICPCN was born from the recognition of the gaps in service provision for children's palliative care and the need to collaborate, network, and share resources. Established in 2005 during a meeting in Seoul, South Korea, the ICPCN has developed over the years into an established network with a global membership. The history of the organization is described, including some of the key events since its inception. Working in collaboration with others, ICPCN has five key focus areas: Communication; Advocacy; Research; Education; and Strategic development, and is the only international charity working globally for the rights of children with palliative care needs. Activities in these areas are discussed, along with the inter-connection between the five areas. Without the ICPCN, palliative care for children would not have developed as far as it has over the years and the organization is committed to ongoing work in this area until all children requiring palliative care have access to quality services, wherever they live around the world. Copyright © 2017 American Academy of Hospice and Palliative Medicine. Published by Elsevier Inc. All rights reserved.

  3. Reduction rules-based search algorithm for opportunistic replacement strategy of multiple life-limited parts

    Directory of Open Access Journals (Sweden)

    Xuyun FU

    2018-01-01

    Full Text Available The opportunistic replacement of multiple Life-Limited Parts (LLPs is a problem widely existing in industry. The replacement strategy of LLPs has a great impact on the total maintenance cost to a lot of equipment. This article focuses on finding a quick and effective algorithm for this problem. To improve the algorithm efficiency, six reduction rules are suggested from the perspectives of solution feasibility, determination of the replacement of LLPs, determination of the maintenance occasion and solution optimality. Based on these six reduction rules, a search algorithm is proposed. This search algorithm can identify one or several optimal solutions. A numerical experiment shows that these six reduction rules are effective, and the time consumed by the algorithm is less than 38 s if the total life of equipment is shorter than 55000 and the number of LLPs is less than 11. A specific case shows that the algorithm can obtain optimal solutions which are much better than the result of the traditional method in 10 s, and it can provide support for determining to-be-replaced LLPs when determining the maintenance workscope of an aircraft engine. Therefore, the algorithm is applicable to engineering applications concerning opportunistic replacement of multiple LLPs in aircraft engines.

  4. Intra- and Trans-Generational Costs of Reduced Female Body Size Caused by Food Limitation Early in Life in Mites

    OpenAIRE

    Walzer, Andreas; Schausberger, Peter

    2013-01-01

    Background Food limitation early in life may be compensated for by developmental plasticity resulting in accelerated development enhancing survival at the expense of small adult body size. However and especially for females in non-matching maternal and offspring environments, being smaller than the standard may incur considerable intra- and trans-generational costs. Methodology/Principal Findings Here, we evaluated the costs of small female body size induced by food limitation early in life i...

  5. Comparison of Quantity Versus Quality Using Performance, Reliability, and Life Cycle Cost Data. A Case Study of the F-15, F-16, and A-10 Aircraft.

    Science.gov (United States)

    1985-09-01

    CoC S~04 COMPARISON OF QUANTITY VERSUS QUALITY USING PERFORMANCE, RELIABILITY, AND LIFE CYCLE COST DATA. A CASE STUDY OF THE F-15, F-16, AND A-10...CYCLE COSTIATU.AT CAE AIR ORE HEO OG .- jAITR UIVERSITY W right.,Patterson Air Force Base, Ohio .! 5ൔ ,6 198 C.IT. U AF’IT/GSL,4/L3Q/65:S Ŗ J...COMPARISON OF QUANTITY VERSUS QUALITY USING PERFORMANCE, RELIABILITY, AND LIFE CYCLE COST DATA. A CASE STUDY OF THE F-15, F-16, AND A-10 AIRCRAFT THESIS David

  6. Analysis and Application of Reliability

    International Nuclear Information System (INIS)

    Jeong, Hae Seong; Park, Dong Ho; Kim, Jae Ju

    1999-05-01

    This book tells of analysis and application of reliability, which includes definition, importance and historical background of reliability, function of reliability and failure rate, life distribution and assumption of reliability, reliability of unrepaired system, reliability of repairable system, sampling test of reliability, failure analysis like failure analysis by FEMA and FTA, and cases, accelerated life testing such as basic conception, acceleration and acceleration factor, and analysis of accelerated life testing data, maintenance policy about alternation and inspection.

  7. Individualised advance care planning in children with life-limiting conditions.

    Science.gov (United States)

    Loeffen, Erik A H; Tissing, Wim J E; Schuiling-Otten, Meggi A; de Kruiff, Chris C; Kremer, Leontien C M; Verhagen, A A Eduard

    2018-05-01

    In 2013, the Pediatric Association of the Netherlands launched an evidence-based guideline 'Palliative care for children'. To promote implementation in daily practice and hereby improve quality of paediatric palliative care, we aimed to develop a functional individualised paediatric palliative care plan (IPPCP) that covers physical, psychological, spiritual and social functioning, with great emphasis on the guideline's recommendations, advance care planning and patients' and parents' preferences and desires. A Dutch working group (28 individuals) with a strong multidisciplinary character developed a draft IPPCP, which was piloted retrospectively and prospectively. In the pilots we completed, the IPPCPs for patients who were recently diagnosed with a life-threatening or life-limiting condition and evaluated completeness, usability and user-friendliness. The final IPPCP comprised five domains: (1) IPPCP data, (2) basics, (3) social, (4) psychosocial and spiritual and (5) physical care. Each domain covered various components. In both pilots, the IPPCP was considered a comprehensive document that covered all areas of paediatric palliative care and was experienced as an improvement to the present situation. However, the current form was regarded to lack user-friendliness. We propose a set of essential components of a comprehensive IPPCP for paediatric palliative care with extra attention for advance care planning and anticipatory action. Patients' and parents' preferences and desires are included next to the recommendations of the evidence-based guideline 'Palliative care for children'. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

  8. 24. MPA-seminar: safety and reliability of plant technology with special emphasis on integrity and life management. Vol. 1. Papers 1-27

    International Nuclear Information System (INIS)

    1999-01-01

    The first volume is dedicated to the safety and reliability of plant technology with special emphasis on the integrity and life management. The main topic in the volume is the contribution of nondestructive testing to the reactor safety from an international point of view. All 20 papers are separately analyzed for this database. (orig.)

  9. Health-related quality of life: validity, reliability, and responsiveness of SF-36, 15D, EQ-5D RAQoL, and HAQ in patients with rheumatoid arthritis

    DEFF Research Database (Denmark)

    Linde, L.; Sørensen, J.; Østergaard, Morten

    2008-01-01

    OBJECTIVE: To compare validity, reliability, and responsiveness of generic and disease specific health-related quality of life (HRQOL) instruments in rheumatoid arthritis (RA). METHODS: Two samples of patients completed the Medical Outcomes Study Short Form-36 Health Survey (SF-36), EuroQol (EQ)-5D...... and VAS pain were responsive to both improvement and deterioration. CONCLUSION: All instruments were valid measures for HRQOL in RA. The RAQoL and HAQ displayed the best reliability, while the SF-36 bodily pain scale and VAS pain were the most responsive. The choice of instrument should depend......, 15D, Rheumatoid Arthritis Quality of Life Scale (RAQoL), Health Assessment Questionnaire (HAQ), and visual analog scales (VAS) for pain, fatigue, and global RA. Validity (convergent, discriminant, and known-groups) was evaluated in a cross-section of 200 patients. Reliability was evaluated...

  10. A reliable incremental method of computing the limit load in deformation plasticity based on compliance: Continuous and discrete setting

    Czech Academy of Sciences Publication Activity Database

    Haslinger, Jaroslav; Repin, S.; Sysala, Stanislav

    2016-01-01

    Roč. 303, September 2016 (2016), s. 156-170 ISSN 0377-0427 R&D Projects: GA MŠk LQ1602; GA ČR GA13-18652S Institutional support: RVO:68145535 Keywords : variational problems with linear growth energy * incremental limit analysis * elastic-perfectly plastic problems * finite element approximation Subject RIV: BA - General Mathematics Impact factor: 1.357, year: 2016 http://www.sciencedirect.com/science/article/pii/S0377042716300917

  11. Detangling the Effects of Environmental Filtering and Dispersal Limitation on Aggregated Distributions of Tree and Shrub Species: Life Stage Matters

    Science.gov (United States)

    Liu, He-Ming; Wang, Zhang-Hua; Ma, Zun-Ping; Fang, Xiao-Feng; Zhang, Jian; Wang, Xi-Hua

    2016-01-01

    The pervasive pattern of aggregated tree distributions in natural communities is commonly explained by the joint effect of two clustering processes: environmental filtering and dispersal limitation, yet little consensus remains on the relative importance of the two clustering processes on tree aggregations. Different life stages of examined species were thought to be one possible explanation of this disagreement, because the effect of environmental filtering and dispersal limitation are expected to increase and decrease with tree life stages, respectively. However, few studies have explicitly tested these expectations. In this study, we evaluated these expectations by three different methods (species-habitat association test based on Poisson Clustering model and spatial point pattern analyses based on Heterogeneous Poisson model and the jointly modeling approach) using 36 species in a 20-ha subtropical forest plot. Our results showed that the percentage of species with significant habitat association increased with life stages, and there were fewer species affected by dispersal limitation in later life stages compared with those in earlier stages. Percentage of variance explained by the environmental filtering and dispersal limitation also increases and decreases with life stages. These results provided a promising alternative explanation on the existing mixed results about the relative importance of the two clustering processes. These findings also highlighted the importance of plant life stages for fully understanding species distributions and species coexistence. PMID:27227538

  12. Early unexpected diagnosis of fetal life-limiting malformation; antenatal palliative care and parental decision.

    Science.gov (United States)

    Mariona, Federico; Burnett, Marianne; Zoma, Melody; Blake, Janice; Khouri, Hanna

    2017-11-02

    Conjoined twins are an infrequent occurrence in obstetric practice. Live-conjoined twins on a late preterm triplet pregnancy is an even rarer event. The objective of this study is to emphasize the critical importance of perinatal palliative care and non-directive parental counseling, informed decision making and respect for autonomy following full disclosure of findings, fetal life-limiting diagnosis, treatment alternatives, maternal-fetal potential complications, and most likely perinatal outcomes. Early surprise prenatal diagnosis, comprehensive parental counseling, palliative care, and perinatal care of a set of conjoined twins and a singleton. Cesarean delivery of a set of conjoined twins and a singleton at 34 weeks' gestation. Immediate neonatal death of the conjoined twins, intact survival, and discharge of the singleton. Review of the database on previously reported similar cases. It is very important to utilize simple and direct language for parents to understand the grave prognosis to the pregnancy. Care alternatives in view of the maternal physical risks and psychological impact of carrying a high order abnormal multiple pregnancy, along with the possible side effects on the singleton.

  13. At limits of life: multidisciplinary insights reveal environmental constraints on biotic diversity in continental Antarctica.

    Directory of Open Access Journals (Sweden)

    Catarina Magalhães

    Full Text Available Multitrophic communities that maintain the functionality of the extreme Antarctic terrestrial ecosystems, while the simplest of any natural community, are still challenging our knowledge about the limits to life on earth. In this study, we describe and interpret the linkage between the diversity of different trophic level communities to the geological morphology and soil geochemistry in the remote Transantarctic Mountains (Darwin Mountains, 80°S. We examined the distribution and diversity of biota (bacteria, cyanobacteria, lichens, algae, invertebrates with respect to elevation, age of glacial drift sheets, and soil physicochemistry. Results showed an abiotic spatial gradient with respect to the diversity of the organisms across different trophic levels. More complex communities, in terms of trophic level diversity, were related to the weakly developed younger drifts (Hatherton and Britannia with higher soil C/N ratio and lower total soluble salts content (thus lower conductivity. Our results indicate that an increase of ion concentration from younger to older drift regions drives a succession of complex to more simple communities, in terms of number of trophic levels and diversity within each group of organisms analysed. This study revealed that integrating diversity across multi-trophic levels of biotic communities with abiotic spatial heterogeneity and geological history is fundamental to understand environmental constraints influencing biological distribution in Antarctic soil ecosystems.

  14. Reliability training

    Science.gov (United States)

    Lalli, Vincent R. (Editor); Malec, Henry A. (Editor); Dillard, Richard B.; Wong, Kam L.; Barber, Frank J.; Barina, Frank J.

    1992-01-01

    Discussed here is failure physics, the study of how products, hardware, software, and systems fail and what can be done about it. The intent is to impart useful information, to extend the limits of production capability, and to assist in achieving low cost reliable products. A review of reliability for the years 1940 to 2000 is given. Next, a review of mathematics is given as well as a description of what elements contribute to product failures. Basic reliability theory and the disciplines that allow us to control and eliminate failures are elucidated.

  15. Brain death organ donation potential and life support therapy limitation in neurocritical patients.

    Science.gov (United States)

    Bodí, M A; Pont, T; Sandiumenge, A; Oliver, E; Gener, J; Badía, M; Mestre, J; Muñoz, E; Esquirol, X; Llauradó, M; Twose, J; Quintana, S

    2015-01-01

    To analyze the profile, incidence of life support therapy limitation (LSTL) and donation potential in neurocritical patients. A multicenter prospective study was carried out. Nine hospitals authorized for organ harvesting for transplantation. All patients consecutively admitted to the hospital with GCS < 8 during a 6-month period were followed-up until discharge or day 30 of hospital stay. Demographic data, cause of coma, clinical status upon admission and outcome were analyzed. LSTL, brain death (BD) and organ donation incidence were recorded. A total of 549 patients were included, with a mean age of 59.0 ± 14.5 years. The cause of coma was cerebral hemorrhage in 27.0% of the cases.LSTL was applied in 176 patients (32.1%). In 78 cases LSTL consisted of avoiding ICU admission. Age, the presence of contraindications, and specific causes of coma were associated to LSTL. A total of 58.1% of the patients died (n=319). One-hundred and thirty-three developed BD (24.2%), and 56.4% of these became organ donors (n=75). The presence of edema and mid-line shift on the CT scan, and transplant coordinator evaluation were associated to BD. LSTL was associated to a no-BD outcome. Early LSTL (first 4 days) was applied in 9 patients under 80 years of age, with no medical contraindications for donation and a GCS ≤ 4 who finally died in asystole. LSTL is a frequent practice in neurocritical patients. In almost one-half of the cases, LSTL consisted of avoiding admission to the ICU, and on several occasions the donation potential was not evaluated by the transplant coordinator. Copyright © 2014 Elsevier España, S.L.U. and SEMICYUC. All rights reserved.

  16. Reliability and construct validity of the Instrument to Measure the Impact of Valve Heart Disease on the Patient's Daily Life.

    Science.gov (United States)

    Anjos, Daniela Brianne Martins Dos; Rodrigues, Roberta Cunha Matheus; Padilha, Kátia Melissa; Pedrosa, Rafaela Batista Dos Santos; Gallani, Maria Cecília Bueno Jayme

    2016-12-19

    evaluate the practicality, acceptability and the floor and ceiling effects, estimate the reliability and verify the convergent construct's validity with the instrument called the Heart Valve Disease Impact on daily life (IDCV) of the valve disease in patients with mitral and or aortic heart valve disease. data was obtained from 86 heart valve disease patients through 3 phases: a face to face interview for a socio-demographic and clinic characterization and then other two done through phone calls of the interviewed patients for application of the instrument (test and repeat test). as for the practicality and acceptability, the instrument was applied with an average time of 9,9 minutes and with 110% of responses, respectively. Ceiling and floor effects observed for all domains, especially floor effect. Reliability was tested using the test - repeating pattern to give evidence of temporal stability of the measurement. Significant negative correlations with moderate to strong magnitude were found between the score of the generic question about the impact of the disease and the scores of IDCV, which points to the validity of the instrument convergent construct. the instrument to measure the impact of valve heart disease on the patient's daily life showed evidence of reliability and validity when applied to patients with heart valve disease. avaliar a praticabilidade, aceitabilidade e os efeitos teto e chão, estimar a confiabilidade e verificar a validade de construto convergente do Instrumento para Mensuração do Impacto da Doença no Cotidiano do Valvopata em pacientes com valvopatia mitral e/ou aórtica. dados foram obtidos junto a 86 pacientes valvopatas por meio de três etapas: uma entrevista presencial para caracterização sociodemográfica e clínica e as duas outras realizadas por meio de contato telefônico para as aplicações do instrumento (Teste e teste de repetição). quanto à praticabilidade e aceitabilidade, o instrumento foi aplicado com tempo m

  17. Evaluation of the Fecal Incontinence Quality of Life Scale (FIQL) using item response theory reveals limitations and suggests revisions.

    Science.gov (United States)

    Peterson, Alexander C; Sutherland, Jason M; Liu, Guiping; Crump, R Trafford; Karimuddin, Ahmer A

    2018-06-01

    The Fecal Incontinence Quality of Life Scale (FIQL) is a commonly used patient-reported outcome measure for fecal incontinence, often used in clinical trials, yet has not been validated in English since its initial development. This study uses modern methods to thoroughly evaluate the psychometric characteristics of the FIQL and its potential for differential functioning by gender. This study analyzed prospectively collected patient-reported outcome data from a sample of patients prior to colorectal surgery. Patients were recruited from 14 general and colorectal surgeons in Vancouver Coastal Health hospitals in Vancouver, Canada. Confirmatory factor analysis was used to assess construct validity. Item response theory was used to evaluate test reliability, describe item-level characteristics, identify local item dependence, and test for differential functioning by gender. 236 patients were included for analysis, with mean age 58 and approximately half female. Factor analysis failed to identify the lifestyle, coping, depression, and embarrassment domains, suggesting lack of construct validity. Items demonstrated low difficulty, indicating that the test has the highest reliability among individuals who have low quality of life. Five items are suggested for removal or replacement. Differential test functioning was minimal. This study has identified specific improvements that can be made to each domain of the Fecal Incontinence Quality of Life Scale and to the instrument overall. Formatting, scoring, and instructions may be simplified, and items with higher difficulty developed. The lifestyle domain can be used as is. The embarrassment domain should be significantly revised before use.

  18. Translation, cultural adaptation assessment, and both validity and reliability testing of the kidney disease quality of life - short form version 1.3 for use with Iranian patients

    DEFF Research Database (Denmark)

    Pakpour, Amir; Yekaninejad, Mirsaeed; Mølsted, Stig

    2011-01-01

    AIM: The aims of the study were to translate the Kidney Disease Quality of Life--Short Form version 1.3 (KDQOL-SF ver. 1.3) questionnaire into Iranian (Farsi), and to then assess it in terms of validity and reliability on Iranian patients. METHODS: The questionnaire was first translated into Farsi...... a larger group (212 patients with end-stage renal disease on haemodialysis). Afterwards, reliability was estimated by internal consistency, and validity was assessed using known group comparisons and constructs for the patient group as a whole. Finally, the factor structure of the questionnaire...... be summarized into an 11 factor structure that jointly accounted for 79.81% of the variance. CONCLUSION: The Iranian version of the KDQOL-SF questionnaire is both highly reliable and valid for use with Iranian patients on haemodialysis....

  19. Long-term Impact of Bile Duct Injury on Morbidity, Mortality, Quality of Life, and Work Related Limitations

    NARCIS (Netherlands)

    Booij, Klaske A. C.; de Reuver, Philip R.; van Dieren, Susan; van Delden, Otto M.; Rauws, Erik A.; Busch, Olivier R.; van Gulik, Thomas M.; Gouma, Dirk J.

    2017-01-01

    Assessment of long-term comprehensive outcome of multimodality treatment of bile duct injury (BDI) in terms of morbidity, mortality, quality of life (QoL), survival, and work related limitations. The impact of BDI on work ability is scarcely investigated. BDI patients referred to a tertiary center

  20. Factors that contribute to physician variability in decisions to limit life support in the ICU: a qualitative study.

    Science.gov (United States)

    Wilson, Michael E; Rhudy, Lori M; Ballinger, Beth A; Tescher, Ann N; Pickering, Brian W; Gajic, Ognjen

    2013-06-01

    Our aim was to explore reasons for physician variability in decisions to limit life support in the intensive care unit (ICU) utilizing qualitative methodology. Single center study consisting of semi-structured interviews with experienced physicians and nurses. Seventeen intensivists from medical (n = 7), surgical (n = 5), and anesthesia (n = 5) critical care backgrounds, and ten nurses from medical (n = 5) and surgical (n = 5) ICU backgrounds were interviewed. Principles of grounded theory were used to analyze the interview transcripts. Eleven factors within four categories were identified that influenced physician variability in decisions to limit life support: (1) physician work environment-workload and competing priorities, shift changes and handoffs, and incorporation of nursing input; (2) physician experiences-of unexpected patient survival, and of limiting life support in physician's family; (3) physician attitudes-investment in a good surgical outcome, specialty perspective, values and beliefs; and (4) physician relationship with patient and family-hearing the patient's wishes firsthand, engagement in family communication, and family negotiation. We identified several factors which physicians and nurses perceived were important sources of physician variability in decisions to limit life support. Ways to raise awareness and ameliorate the potentially adverse effects of factors such as workload, competing priorities, shift changes, and handoffs should be explored. Exposing intensivists to long term patient outcomes, formalizing nursing input, providing additional training, and emphasizing firsthand knowledge of patient wishes may improve decision making.

  1. Reliability assessment of shut-off rod drive mechanism for TAPP - 3 and 4 and critical facility through life cycle testing

    International Nuclear Information System (INIS)

    Singh, Manjit; Badodkar, D.N.; Singh, N.K.; Dalal, N.S.; Mishra, M.K.; Veda Vyas, G.; Kothari, C.B.; Rao, V.V.S.S.; Saraf, R.K.

    2006-01-01

    Shut-off rod drive mechanism forms a safety critical system of a nuclear reactor. It is the space constraints for the given reactor layout, which makes design of shut-off rod drive mechanism (SRDM) a custom built design. Design of SRDM adopts fail-safe, replaceability and the simplicity criterion ensuring very high reliability of its operation. Shut-off rod drive mechanism for TAPP-3 and 4 and 'Critical Facility' have been recently designed and developed at Division of Remote Handling and Robotics (DRHR), BARC. These are designed with a number of advanced features and these are significantly different than those used in Dhruva and 220 MWe PHWRs. Design of SRDM is qualified through proto typing and life cycle testing on a full-scale test set-up. This paper gives details of qualification and life cycle test data for prototype SRDM for TAPP-3 and 4 and 'Critical Facility' and reliability assessment. (author)

  2. Life cycle assessment as a method of limitation of a negative environment impact of castings

    Directory of Open Access Journals (Sweden)

    M. Holtzer

    2011-07-01

    Full Text Available Casting production constitutes environmental problems going far beyond the foundry plant area. Applying a notion of the life cycle the input (suppliers side and output factors (clients side can be identified. The foundry plant activities for the environment hazard mitigation can be situated on various stages of the casting life cycle. The environment impact of motorisation castings made of different materials – during the whole life cycle of castings – are discussed in the paper. It starts from the charge material production, then follows via the casting process, car assembly, car exploitation and ends at the car breaking up for scrap.

  3. Reliability engineering

    International Nuclear Information System (INIS)

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

    1993-08-01

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

  4. Reliability-based service life assessment of concrete structures in nuclear power plants: optimum inspection and repair

    International Nuclear Information System (INIS)

    Ellingwood, B.R.; Mori, Y.

    1995-01-01

    Research is being conducted to address aging management of safety-related reinforced concrete structures in nuclear power plants (NPPs). Documentation is being prepared to identify potential structural safety issues and to recommend criteria for use in evaluating reinforced concrete structures for continued service. Time-dependent reliability analysis provides the framework and quantitative tools for the condition assessment. The role of in-service inspection and repair in ensuring continued reliability in-service is examined. (author). 19 refs., 4 figs

  5. Deformation heterogeneities and their role in life-limiting fatigue failures in a two-phase titanium alloy

    International Nuclear Information System (INIS)

    Jha, Sushant K.; Szczepanski, Christopher J.; John, Reji; Larsen, James M.

    2015-01-01

    Fatigue crack-initiation sites in Ti–6Al–2Sn–4Zr–6Mo (Ti–6–2–4–6), an α + β titanium alloy used in turbine engine applications, were characterized with emphasis on distinguishing the microstructural neighborhoods and mechanisms that produce the life-limiting failures vs. those that promote the mean-lifetime behavior. The characterization methods included quantitative tilt fractography, focused ion beam milling across crack-initiation facets, and electron backscattered diffraction analysis. The motivation for discerning between the life-limiting and the mean-dominating crack-initiation microstructural neighborhoods stemmed from the previously developed understanding that the mean and the life-limiting behaviors respond differently to stress level (and many other variables), leading to an increasing separation between the two subpopulations as the stress level is decreased, thereby increasing the variability in lifetime. The different rates of response of the two behaviors was found to arise because the life-limiting mechanism was dominated by the crack-growth lifetime, with microstructural-scale crack-initiation occurring within the first few fatigue cycles, whereas the mean behavior was increasingly dominated by the crack-initiation lifetime as the stress level was decreased. Representative specimens for 2-D characterization of crack-initiation neighborhoods were selected from life-limiting and mean-dominating populations generated by fatigue tests on a duplex α + β phase microstructure of Ti–6–2–4–6 under a narrow range of applied stress amplitudes. A compilation of data on the crack-initiation facet and the neighborhood of the faceted grain from multiple specimens pointed to at least four categories of critical microstructural configurations, each representing a set of necessary (but perhaps not sufficient) conditions for crack-initiation in this alloy. Based on this characterization, a hypothesis for the life-limiting fatigue behavior

  6. Technical limits on performance reserves and life expectancy in nuclear power stations with light water reactors

    International Nuclear Information System (INIS)

    Wanner, R.; Brosi, S.; Duijvestijn, G.

    1990-01-01

    The safety margin (i.e. the difference between the loads equipment can take and those actually imposed on components) in a reactor pressure vessel is a major factor in the life expectancy of a nuclear power station. This safety margin is reduced considerably by reductions in the toughness of equipment caused by neutron irradiation and growth of cracks. Once the minimum safety margin is infringed, the nuclear power station is at the end of its working life. 13 figs., 11 refs

  7. The limits of extremophilic life expanded under extraterrestrial environment-simulated experiments

    Science.gov (United States)

    Lage, C.; Dalmaso, G.; Teixeira, L.; Bendia, A.; Rosado, A.

    2012-09-01

    Astrobiology is a brand new area of science that seeks to understand the origin and dynamics of life in the universe. Several hypotheses to explain life in the cosmic context have been developed throughout human history, but only now technology has allowed many of them to be tested. Laboratory experiments have been able to show how chemical elements essential to life, carbon, nitrogen, oxygen and hydrogen combine in biologically important compounds. Interestingly, these compounds are found universally. As these compounds were combined to the point of originating cells and complex organisms is still a challenge to be unveiled by science. However, our 4.5 billion years-old solar system was born within a 10-billion years-old universe. Thus, simple cells like microorganisms may have had time to form in planets older than ours or other suitable molecular places in the universe. One hypothesis to explain the origin of life on Earth is called panspermia, which predicts that microbial life could have been formed in the universe billions of years ago, traveling between planets, and inseminating units of life that could have become more complex in habitable planets like ours. A project designed to test the viability of extremophile microorganisms exposed to simulated extraterrestrial environments is ongoing at the Carlos Chagas Filho Institute of Biophysics to test whether microbial life could withstand those inhospitable environments. Ultra-resistant (known or novel ones) microorganisms collected from terrestrial extreme environments, extremophiles, have been exposed to intense radiation sources simulating solar radiation (at synchrotron accelerators), capable of emitting in a few hours radiation equivalent of million years accumulated doses. The results obtained in these experiments reveal the interesting possibility of the existence of microbial life beyond Earth.

  8. Psychiatry trainees' views and educational needs regarding the care of patients with a life-limiting illness.

    Science.gov (United States)

    Forster, Benjamin C; Proskurin, Helen; Kelly, Brian; Lovell, Melanie R; Ilchef, Ralf; Clayton, Josephine M

    2017-04-01

    People with a life-limiting physical illness experience high rates of significant psychological and psychiatric morbidity. Nevertheless, psychiatrists often report feeling ill-equipped to respond to the psychiatric needs of this population. Our aim was to explore psychiatry trainees' views and educational needs regarding the care of patients with a life-limiting physical illness. Using semistructured interviews, participants' opinions were sought on the role of psychiatrists in the care of patients with a life-limiting illness and their caregivers, the challenges faced within the role, and the educational needs involved in providing care for these patients. Interviews were audiotaped, fully transcribed, and then subjected to thematic analysis. A total of 17 psychiatry trainees were recruited through two large psychiatry training networks in New South Wales, Australia. There were contrasting views on the role of psychiatry in life-limiting illness. Some reported that a humanistic, supportive approach including elements of psychotherapy was helpful, even in the absence of a recognizable mental disorder. Those who reported a more biological and clinical stance (with a reliance on pharmacotherapy) tended to have a nihilistic view of psychiatric intervention in this setting. Trainees generally felt ill-prepared to talk to dying patients and felt there was an educational "famine" in this area of psychiatry. They expressed a desire for more training and thought that increased mentorship and case-based learning, including input from palliative care clinicians, would be most helpful. Participants generally feel unprepared to care for patients with a life-limiting physical illness and have contrasting views on the role of psychiatry in this setting. Targeted education is required for psychiatry trainees in order to equip them to care for these patients.

  9. Aborto e eutanásia: dilemas contemporâneos sobre os limites da vida Abortion and euthanasia: contemporary issues on the limits of life

    Directory of Open Access Journals (Sweden)

    Edlaine de Campos Gomes

    2008-01-01

    Full Text Available Este artigo analisa a polêmica em torno da determinação dos limites da vida, a partir do pressuposto de que a demarcação das fronteiras entre vida e morte envolve questões culturais, sociais, religiosas e políticas referentes à gestão da pessoa. Debates acerca do aborto e da eutanásia evidenciam concepções morais sobre os direitos individuais que, por sua vez, são passíveis de normatização em cada contexto. Tais temas revelam para além da criação e do desenvolvimento de novas tecnologias médicas, direcionadas à reprodução assistida, medicina fetal e manutenção artificial da vida, seja de prematuros ou de doentes fora de possibilidades de cura valores e posicionamentos, muitas vezes contrastivos. A partir de levantamento de projetos de lei apresentados no âmbito legislativo brasileiro, constatou-se a presença de discursos opostos, oriundos da religião e de defensores da autonomia individual, o que ilustra os dilemas contemporâneos sobre os limites da vida.This article analyzes the controversy surrounding what can be established as the limit of life, from the presumption that the frontier marks between life and death involve cultural, social, religious and political issues referred to personhood management. Debates about abortion and euthanasia make it clear that moral concepts on individual rights can be standardized in each context. These themes reveal beyond new medical technology creation and development, focused on assisted fertilization, fetal medicine and maintaining life artificially, either for premature babies or patients without possibilities of cure values and viewpoints, often opposed. From the survey of law projects, presented within Brazilian legislative field, opposite positions were revealed, from religion and defenders of individual autonomy, which illustrates the contemporary dilemmas on the limits of life.

  10. THE LOWER LIMIT OF THE RIGHT TO LIFE OF THE PERSON IN THE LIGHT OF THE NEW CRIMINAL CODE

    Directory of Open Access Journals (Sweden)

    MIHAELA (ROTARU MOISE

    2012-05-01

    Full Text Available The right to life is one of the fundamental human rights both nationally and internationally, being provided and guaranteed by a series of legal acts. In the Romanian law, the right to life of the person as guaranteed by the article 22 paragraph (1 of the Constitution is also protected by criminal law. In judicial practice in this matter there was an important and interesting issue regarding the limits of the right to life of people or accurately determining the starting and ending of a person’s life. On this aspect, there were several points of view in the law literature, each grounded on its own way. In the current criminal law, the two aspects that I have mentioned above are linked, on the one hand, for instance to the issue of the legal classification of the fetal injury during birth until the cut of the umbilical cord and, on the other hand, to the thesis of tissue and organs for transplantation. The new Criminal Code is inspired by the European legislation. In relation to the criminal offences against the person it brings news to us by introducing a new offence, namely fetal injury, referred to in the article 202. Analyzing the legal content of this offence it is impossible not to call into question the situation of the lower limit of the right to life of the person.

  11. Validity and Reliability of the Dutch Adaptation of the Psoriatic Arthritis Quality of Life (PsAQoL) Questionnaire

    NARCIS (Netherlands)

    Wink, Freke; Arends, Suzanne; McKenna, Stephen P; Houtman, Pieternella M; Brouwer, Elisabeth; Spoorenberg, Anneke

    2013-01-01

    Objective: The Psoriatic Arthritis Quality of Life (PsAQoL) questionnaire is a disease-specific instrument developed to measure quality of life (QoL) in patients with psoriatic arthritis (PsA). The aim of this study was to translate the measure into Dutch and to determine its psychometric

  12. Quality of life in oncological patients with oropharyngeal dysphagia: validity and reliability of the Dutch version of the MD Anderson Dysphagia Inventory and the Deglutition Handicap Index.

    Science.gov (United States)

    Speyer, Renée; Heijnen, Bas J; Baijens, Laura W; Vrijenhoef, Femke H; Otters, Elsemieke F; Roodenburg, Nel; Bogaardt, Hans C

    2011-12-01

    Quality of life is an important outcome measurement in objectifying the current health status or therapy effects in patients with oropharyngeal dysphagia. In this study, the validity and reliability of the Dutch version of the Deglutition Handicap Index (DHI) and the MD Anderson Dysphagia Inventory (MDADI) have been determined for oncological patients with oropharyngeal dysphagia. At Maastricht University Medical Center, 76 consecutive patients were selected and asked to fill in three questionnaires on quality of life related to oropharyngeal dysphagia (the SWAL-QOL, the MDADI, and the DHI) as well as a simple one-item visual analog Dysphagia Severity Scale. None of the quality-of-life questionnaires showed any floor or ceiling effect. The test-retest reliability of the MDADI and the Dysphagia Severity Scale proved to be good. The test-retest reliability of the DHI could not be determined because of insufficient data, but the intraclass correlation coefficients were rather high. The internal consistency proved to be good. However, confirmatory factor analysis could not distinguish the underlying constructs as defined by the subscales per questionnaire. When assessing criterion validity, both the MDADI and the DHI showed satisfactory associations with the SWAL-QOL (reference or gold standard) after having removed the less relevant subscales of the SWAL-QOL. In conclusion, when assessing the validity and reliability of the Dutch version of the DHI or the MDADI, not all psychometric properties have been adequately met. In general, because of difficulties in the interpretation of study results when using questionnaires lacking sufficient psychometric quality, it is recommended that researchers strive to use questionnaires with the most optimal psychometric properties.

  13. Validity, reliability and understanding of the EORTC-C30 and EORTC-BR23, quality of life questionnaires specific for breast cancer

    Directory of Open Access Journals (Sweden)

    Fernanda Alessandra Silva Michels

    2013-06-01

    Full Text Available Objective: To validate and assess reliability and understanding of the EORTC–C30 quality of life questionnaire and its breast cancer specific module, the EORTC-BR23. Methods: This study was conducted at the AC Camargo Cancer Hospital, São Paulo, Brazil. A total of 100 women diagnosed with breast cancer were interviewed. Internal consistency, confirmatory factorial analysis, convergent validity, construct validity and degree of understanding were examined. Reliability was assessed by comparison of means at times 1 and 2, inter-class coefficient and Bland-Altman graphics. Results: Cronbach’s alpha ranged from 0.72 to 0.86 for the EORTC-C30 and from 0.78 to 0.83 for the EORTC-BR23 questionnaire. Most questions were confirmed in the confirmatory factorial analysis. In the construct validity analysis, the questionnaires were capable of differentiating patients with or without lymphedema, apart from the symptom scales of both questionnaires. Both questionnaires presented a significant correlation in most domains of the SF-36, in the convergent validity analysis. Only a few criticisms were reported concerning questions, and the mean grade of understanding was high (C30 = 4.91 and BR23 = 4.89. The questionnaires presented good rates of reliability, with the exception of the functional scale of the C30 and the symptom scale of the BR23. Conclusions: The EORTC-C30 and EORTC-BR23 quality of life questionnaires were validated, presented good rates of reliability and are easily understood, allowing them to be used in Brazil to assess quality of life among women with breast cancer.

  14. Validity and reliability of the Iranian version of the Pediatric Quality of Life Inventory™ 4.0 (PedsQL™ Generic Core Scales in children

    Directory of Open Access Journals (Sweden)

    Amiri Parisa

    2012-01-01

    Full Text Available Abstract Background This study aimed to investigate the reliability and validity of the Iranian version of the Pediatric Quality of Life Inventory™ 4.0 (PedsQL™ 4.0 Generic Core Scales in children. Methods A standard forward and backward translation procedure was used to translate the US English version of the PedsQL™ 4.0 Generic Core Scales for children into the Iranian language (Persian. The Iranian version of the PedsQL™ 4.0 Generic Core Scales was completed by 503 healthy and 22 chronically ill children aged 8-12 years and their parents. The reliability was evaluated using internal consistency. Known-groups discriminant comparisons were made, and exploratory factor analysis (EFA and confirmatory factor analysis (CFA were conducted. Results The internal consistency, as measured by Cronbach's alpha coefficients, exceeded the minimum reliability standard of 0.70. All monotrait-multimethod correlations were higher than multitrait-multimethod correlations. The intraclass correlation coefficients (ICC between the children self-report and parent proxy-reports showed moderate to high agreement. Exploratory factor analysis extracted six factors from the PedsQL™ 4.0 for both self and proxy reports, accounting for 47.9% and 54.8% of total variance, respectively. The results of the confirmatory factor analysis for 6-factor models for both self-report and proxy-report indicated acceptable fit for the proposed models. Regarding health status, as hypothesized from previous studies, healthy children reported significantly higher health-related quality of life than those with chronic illnesses. Conclusions The findings support the initial reliability and validity of the Iranian version of the PedsQL™ 4.0 as a generic instrument to measure health-related quality of life of children in Iran.

  15. Using Rasch Analysis to Evaluate the Reliability and Validity of the Swallowing Quality of Life Questionnaire: An Item Response Theory Approach.

    Science.gov (United States)

    Cordier, Reinie; Speyer, Renée; Schindler, Antonio; Michou, Emilia; Heijnen, Bas Joris; Baijens, Laura; Karaduman, Ayşe; Swan, Katina; Clavé, Pere; Joosten, Annette Veronica

    2018-02-01

    The Swallowing Quality of Life questionnaire (SWAL-QOL) is widely used clinically and in research to evaluate quality of life related to swallowing difficulties. It has been described as a valid and reliable tool, but was developed and tested using classic test theory. This study describes the reliability and validity of the SWAL-QOL using item response theory (IRT; Rasch analysis). SWAL-QOL data were gathered from 507 participants at risk of oropharyngeal dysphagia (OD) across four European countries. OD was confirmed in 75.7% of participants via videofluoroscopy and/or fiberoptic endoscopic evaluation, or a clinical diagnosis based on meeting selected criteria. Patients with esophageal dysphagia were excluded. Data were analysed using Rasch analysis. Item and person reliability was good for all the items combined. However, person reliability was poor for 8 subscales and item reliability was poor for one subscale. Eight subscales exhibited poor person separation and two exhibited poor item separation. Overall item and person fit statistics were acceptable. However, at an individual item fit level results indicated unpredictable item responses for 28 items, and item redundancy for 10 items. The item-person dimensionality map confirmed these findings. Results from the overall Rasch model fit and Principal Component Analysis were suggestive of a second dimension. For all the items combined, none of the item categories were 'category', 'threshold' or 'step' disordered; however, all subscales demonstrated category disordered functioning. Findings suggest an urgent need to further investigate the underlying structure of the SWAL-QOL and its psychometric characteristics using IRT.

  16. Education, Functional Limitations, and Life Satisfaction among Older Adults in South Korea

    Science.gov (United States)

    Lee, Eun-Kyoung Othelia; Lee, Jungui

    2013-01-01

    This study examined the associations of educational level with functioning and life satisfaction among community-dwelling older adults in South Korea ("n" = 4,152). The sample was drawn from Wave I of the Korean Longitudinal Study on Aging. To examine educational disparities, separate analyses were run to note predictors in less educated…

  17. Measuring the quality of life in mild to very severe dementia: testing the inter-rater and intra-rater reliability of the German version of the QUALIDEM.

    Science.gov (United States)

    Dichter, Martin Nikolaus; Schwab, Christian G G; Meyer, Gabriele; Bartholomeyczik, Sabine; Dortmann, Olga; Halek, Margareta

    2014-05-01

    Quality of life (Qol) is an increasingly used outcome measure in dementia research. The QUALIDEM is a dementia-specific and proxy-rated Qol instrument. We aimed to determine the inter-rater and intra-rater reliability in residents with dementia in German nursing homes. The QUALIDEM consists of nine subscales that were applied to a sample of 108 people with mild to severe dementia and six consecutive subscales that were applied to a sample of 53 people with very severe dementia. The proxy raters were 49 registered nurses and nursing assistants. Inter-rater and intra-rater reliability scores were calculated on the subscale and item level. None of the QUALIDEM subscales showed strong inter-rater reliability based on the single-measure Intra-Class Correlation Coefficient (ICC) for absolute agreement ≥ 0.70. Based on the average-measure ICC for four raters, eight subscales for people with mild to severe dementia (care relationship, positive affect, negative affect, restless tense behavior, social relations, social isolation, feeling at home and having something to do) and five subscales for very severe dementia (care relationship, negative affect, restless tense behavior, social relations and social isolation) yielded a strong inter-rater agreement (ICC: 0.72-0.86). All of the QUALIDEM subscales, regardless of dementia severity, showed strong intra-rater agreement. The ICC values ranged between 0.70 and 0.79 for people with mild to severe dementia and between 0.75 and 0.87 for people with very severe dementia. This study demonstrated insufficient inter-rater reliability and sufficient intra-rater reliability for all subscales of both versions of the German QUALIDEM. The degree of inter-rater reliability can be improved by collaborative Qol rating by more than one nurse. The development of a measurement manual with accurate item definitions and a standardized education program for proxy raters is recommended.

  18. Evaluating the reliability of Persian version of ankylosing spondylitis quality of life (ASQoL) questionnaire and related clinical and demographic parameters in patients with ankylosing spondylitis.

    Science.gov (United States)

    Fallahi, Sasan; Jamshidi, Ahmad Reza; Bidad, Katayoon; Qorbani, Mostafa; Mahmoudi, Mahdi

    2014-06-01

    Ankylosing spondylitis quality of life (ASQoL) is an instrument for assessing quality of life (QoL). The aims of this study were to assess the reliability of Persian version of ASQoL questionnaire and evaluation of QoL status and related factors in ankylosing spondylitis (AS). One hundred and sixty-three Iranian patients with AS who fulfilled modified New York criteria were enrolled. Patients were evaluated using questionnaires including demographic and clinical variables, Bath AS Disease Activity Index (BASDAI), Bath AS Functional Index (BASFI), fatigue, Bath AS Metrology Index, pain and ASQoL. Reliability and validity of Persian version of ASQoL were evaluated by test-re-test agreement, internal consistency and correlation with specific scales. Relationship of parameters with ASQoL was analyzed by multiple regression. Age, disease duration and ASQoL score (mean ± SD) were 37.74 ± 9.88, 14.49 ± 8.47 and 8.02 ± 5.28 years, respectively. Test-re-test reproducibility for ASQoL was good as assessed by intra-class correlation coefficient (ICC: 0.97, P educational level, r = -0.37). Persian version of ASQoL is a valid and reliable scale to assess QoL in AS. Function, fatigue, mood, hip mobility and education are the factors which should be noted to achieve the best QoL.

  19. Reliability and Validity of the English-, Chinese- and Malay-Language Versions of the World Health Organization Quality of Life (WHOQOL-BREF) Questionnaire in Singapore.

    Science.gov (United States)

    Cheung, Yin Bun; Yeo, Khung Keong; Chong, Kok Joon; Khoo, Eric Yh; Wee, Hwee Lin

    2017-12-01

    The World Health Organization Quality of Life (WHOQOL-BREF) questionnaire is a 26-item questionnaire that evaluates 4 domains of quality of life (QoL), namely Physical, Psychological, Social Relationships and Environment. This study aimed to evaluate the validity and reliability of the WHOQOL-BREF among Singapore residents aged 21 and above. We recruited participants from the general population by using multistage cluster sampling and participants from 2 hospitals by using convenience sampling. Participants completed either English, Chinese or Malay versions of the WHOQOL-BREF and the EuroQoL 5 Dimension 5 Levels (EQ-5D-5L) questionnaires. Confirmatory factor analysis, known-group validity, internal consistency (Cronbach's alpha) and test-retest reliability using the intraclass correlation coefficient (ICC) were performed. Data from 1316 participants were analysed (Chinese: 46.9%, Malay: 41.0% and Indian: 11.7%; 57.5% mean, mean standard deviation [SD, range] age: 51.9 [15.68, 24 to 90] years); 154 participants took part in the retest in various languages (English: 60, Chinese: 49 and Malay: 45). Tucker-Lewis Index (TLI) was 0.919, 0.913 and 0.909 for the English, Chinese and Malay versions, respectively. Cronbach's alpha exceeded 0.7 and ICC exceeded 0.4 for all domains in all language versions. The WHOQOL-BREF is valid and reliable for assessing QoL in Singapore. Model fit is reasonable with room for improvement.

  20. Analysis of Reliability Estimations and Spares Protection Levels on Life Cycle Costs of the Marine Corps H-1 Upgrades Program

    National Research Council Canada - National Science Library

    Thompson, David

    2004-01-01

    .... This will be accomplished through the integration of factors impacting spare parts levels and Life Cycle Costs into a spreadsheet model that will establish the appropriate relationship between the factors...

  1. Should the service life of nuclear power plants be limited for technical reasons?

    International Nuclear Information System (INIS)

    Schomer, E.

    1995-01-01

    German nuclear power plant operating licenses take into account the fact that the design lifetime of the facilities is 40 years. The technological lifetime, however, is governed by actual ageing processes and operational burden. The service life of nuclear power plants can be extended by replacement of the steam generator and by repair or replacement of the reactor pressure vessel or parts thereof. Attention is also paid to the reactor protection systems. (J.B.). 8 figs

  2. Geographic divergence in upper thermal limits across insect life stages: does behavior matter?

    Science.gov (United States)

    MacLean, Heidi J; Higgins, Jessica K; Buckley, Lauren B; Kingsolver, Joel G

    2016-05-01

    Insects with complex life cycles vary in size, mobility, and thermal ecology across life stages. We examine how differences in the capacity for thermoregulatory behavior influence geographic differences in physiological heat tolerance among egg and adult Colias butterflies. Colias adults exhibit differences in morphology (wing melanin and thoracic setal length) along spatial gradients, whereas eggs are morphologically indistinguishable. Here we compare Colias eriphyle eggs and adults from two elevations and Colias meadii from a high elevation. Hatching success and egg development time of C. eriphyle eggs did not differ significantly with the elevation of origin. Egg survival declined in response to heat-shock temperatures above 38-40 °C and egg development time was shortest at intermediate heat-shock temperatures of 33-38 °C. Laboratory experiments with adults showed survival in response to heat shock was significantly greater for Colias from higher than from lower elevation sites. Common-garden experiments at the low-elevation field site showed that C. meadii adults initiated heat-avoidance and over-heating behaviors significantly earlier in the day than C. eriphyle. Our study demonstrates the importance of examining thermal tolerances across life stages. Our findings are inconsistent with the hypothesis that thermoregulatory behavior inhibits the geographic divergence of physiological traits in mobile stages, and suggest that sessile stages may evolve similar heat tolerances in different environments due to microclimatic variability or evolutionary constraints.

  3. Feasibility, reliability and validity of the Thai version of the Pediatric Quality of Life Inventory 3.0 cerebral palsy module.

    Science.gov (United States)

    Tantilipikorn, Pinailug; Watter, Pauline; Prasertsukdee, Saipin

    2013-03-01

    Quality of Life (QOL) and Health-related Quality of Life (HRQOL) are now considered as necessary outcome measures for children with cerebral palsy (CP). Various reliable and valid condition-specific HRQOL tools are available for these children. One of these is Pediatric Quality of Life Inventory (PedsQL) 3.0 CP module which has been widely used and was translated to many languages. As no Thai version is available, the authors have completed this translation. This study then aimed to investigate psychometric properties of the newly translated Thai PedsQL 3.0 CP module and to establish parent confidence in their ratings in the translated tool. Translation of the PedsQL 3.0 CP module was performed based on linguistic translation guidelines. Then, the psychometric properties of the Thai version were established. PedsQL 3.0 CP module was completed by children with CP and their parents or caregivers twice with 2-4 weeks. Respondents were 97 parents or caregivers and 54 children. Minimal missing data were found. Acceptable internal consistency was supported except for Movement and Balance Scale (self-report). Intraclass correlation coefficients for parent proxy and self-report were good to excellent (0.684-0.950). The feasibility, reliability and validity of the translated tool were supported.

  4. Fatigue Reliability of Offshore Wind Turbine Systems

    DEFF Research Database (Denmark)

    Marquez-Dominguez, Sergio; Sørensen, John Dalsgaard

    2012-01-01

    of appropriate partial safety factors / fatigue design factors (FDF) for steel substructures of offshore wind turbines (OWTs). The fatigue life is modeled by the SN approach. Design and limit state equations are established based on the accumulated fatigue damage. The acceptable reliability level for optimal...... fatigue design of OWTs is discussed and results for reliability assessment of typical fatigue critical design of offshore steel support structures are presented....

  5. Validity and reliability of the Brief version of Quality of Life in Bipolar Disorder" (Bref QoL.BD) among Chinese bipolar patients.

    Science.gov (United States)

    Xiao, Lin; Gao, Yulin; Zhang, Lili; Chen, Peiyun; Sun, Xiaojia; Tang, Siyuan

    2016-03-15

    Previous literatures on quality of life (QoL) in bipolar disorder (BD) strongly suggested that a disease-specific QoL measure for patients with BD should be developed to evaluate QoL more specifically and reliably. To our knowledge, "Quality of Life in Bipolar Disorder" (QoL.BD) is the first and only questionnaire produced to specifically measure QoL in people with BD. In China, there is no disease-targeted measure available to specifically measure QoL in Chinese patients with BD. The aim of the study is to revise and validate the brief version of the QoL.BD (Bref QoL.BD ) into Chinese version. All the items of the Bref QoL.BD was translated into Chinese language, using the Brislin translation mode. The questionnaire was administered to a total sample of 231 subjects, including 101 BD patients and 130 healthy controls, to test the psychometric properties of Bref QoL.BD (e.g. internal consistency, retest reliability, content validity, item analysis, confirmatory factor analysis, criterion validity, convergent validity, discriminative validity and feasibility). The Chinese version of the Bref QoL.BD had very high internal consistency (Cronbach's alpha=0.815) and retest reliability (intraclass correlation coefficient (ICC )=0.808). Confirmatory factor analysis (CFA) validated the original one-factor structure. The direction and magnitude of correlations with 36-item Short-Form Health Survey (SF-36; rs= 0.313, Psize from only one tertiary care center. And BD patients enrolled were euthymic, excluding the acute BD patients. The Chinese version of the Bref QoL.BD is a feasible, reliable and valid tool for the assessment of QoL for Chinese BD patients. Copyright © 2015 Elsevier B.V. All rights reserved.

  6. Reliability and validity of a survey to measure bowel function and quality of life in long-term rectal cancer survivors.

    Science.gov (United States)

    Wendel, Christopher S; Grant, Marcia; Herrinton, Lisa; Temple, Larissa K F; Hornbrook, Mark C; McMullen, Carmit K; Bulkley, Joanna E; Altschuler, Andrea; Krouse, Robert S

    2014-12-01

    Examination of reliability and validity of a specialized health-related quality of life questionnaire for rectal cancer (RC) survivors (≥5 years post-diagnosis). We mailed 1,063 Kaiser Permanente (KP) RC survivors (313 ostomy and 750 anastomosis) a questionnaire containing the Modified City of Hope Quality of Life-Ostomy (mCOH-QOL-O), SF-12v2, Duke-UNC Functional Social Support Questionnaire (FSSQ), and Memorial Sloan-Kettering Cancer Center Bowel Function Index (BFI). We adapted certain BFI items for use by subjects with intestinal ostomies. We evaluated reliability for all instruments with inter-item correlations and Cronbach's alpha. We assessed construct validity only for the BFI in the ostomy group, because such use has not been reported. The overall response rate was 60.5 % (577 respondents/953 eligible). Compared with non-responders, participants were on average 2 years younger and more likely non-Hispanic white, resided in educationally non-deprived areas, and had KP membership through a group. The mCOH-QOL-O, SF-12, and FSSQ were found to be highly reliable for RC survivors. In the ostomy group, BFI Urgency/Soilage and Dietary subscales were found to be reliable, but Frequency was not. Factor analysis supported the construct of Urgency/Soilage and Dietary subscales in the ostomy group, although one item had a moderate correlation with all three factors. The BFI also demonstrated good concurrent validity with other instruments in the ostomy group. With possible exception of the BFI Frequency subscale in populations with ostomies, components of our survey can be used for the entire population of RC survivors, no matter whether they received anastomosis or ostomy.

  7. Limiting values for the RBE of fission neutrons at low doses for life shortening in mice

    International Nuclear Information System (INIS)

    Storer, J.B.; Mitchell, T.J.

    1984-01-01

    The authors have analyzed recently published data on the effects of low doses of fission neutrons on the mean survival times of mice. The analysis for single-dose exposures was confined to doses of 20 rad or less, while for fractionated exposures only total doses of 80 rad or less were considered. They fitted the data to the frequently used power function model: life shortening = βD/sup γ/, where D is the radiation dose. They show that, at low doses per fraction, either the effects are not additive or the dose-effect curve for single exposures cannot show a greater negative curvature than about the 0.9 power of dose. Analysis of the data for γ rays showed that an exponent of 1.0 gave an acceptable fit. They conclude that at neutron doses of 20 rad or less the RBE for life shortening is constant and ranges from 13 to 22 depending on mouse strain and sex

  8. Caring for Life-Limiting Illness in Ethiopia: A Mixed-Methods Assessment of Outpatient Palliative Care Needs.

    Science.gov (United States)

    Reid, Eleanor Anderson; Gudina, Esayas Kebede; Ayers, Nicola; Tigineh, Wondimagegnu; Azmera, Yoseph Mamo

    2018-05-01

    Palliative care aims to reduce physical suffering and the emotional, spiritual, and psychosocial distress of life-limiting illness. Palliative care is a human right, yet there are vast disparities in its provision: of the 40 million people globally in need of palliative care, less than 10% receive it, largely in high-income countries. There is a particular paucity of data on palliative care needs across the spectrum of incurable disease in Ethiopia. The aims of this research were to assess the overall burden of life-limiting illness, the costs associated with life-limiting illness, and barriers to accessing palliative care in Ethiopia. Mixed-methods case-series. One hundred adults (mean age: 43.7 ± 14 years, 64% female) were recruited at three outpatient clinics (oncology, HIV, noncommunicable disease) and hospice patient homes in Ethiopia. Four internationally validated questionnaires were used to assess physical symptoms, psychosocial distress, and disability. In-depth interviews gauged poverty level, costs of care, and end-of-life preferences. Qualitative data were analyzed by thematic content, quantitative data by standard descriptive, frequency and regression analyses. In oncology, 95.5% of the population endorsed moderate or severe pain, while 24% were not prescribed analgesia. Importantly, 80% of the noncommunicable disease population reported moderate or severe pain. The mean psychosocial distress score was 6.4/10. Severe disability was reported in 26% of the population, with mobility most affected. Statistically significant relationships were found between pain and costs, and pain and lack of well-being. Very high costs were reported by oncology patients. Oncology withstanding, the majority of subjects wished to die at home. Oncology patients cited pain control as the top reason they preferred a hospital death. There are extensive unmet palliative care needs in Ethiopia. Untreated pain and high costs of illness are the major contributors to

  9. Equilibrium moisture content of wood at different temperature/moisture conditions in the cladding of wooden constructions and in the relation to their reliability and service life

    OpenAIRE

    Zdeňka Havířová; Pavel Kubů

    2010-01-01

    One of the natural properties of wood and wood-based materials is their soaking capacity (hy­gro­sco­pi­ci­ty). The moisture content of wood and building constructions of wood and wood based materials significantly influences the service life and reliability of these constructions and buildings. The equilibrium weight moisture content of built-in wood corresponding to temperature/moisture conditions inside the cladding has therefore a decisive influence on the basic requirements placed on bui...

  10. Analyses of inter-rater reliability between professionals, medical students and trained school children as assessors of basic life support skills.

    Science.gov (United States)

    Beck, Stefanie; Ruhnke, Bjarne; Issleib, Malte; Daubmann, Anne; Harendza, Sigrid; Zöllner, Christian

    2016-10-07

    Training of lay-rescuers is essential to improve survival-rates after cardiac arrest. Multiple campaigns emphasise the importance of basic life support (BLS) training for school children. Trainings require a valid assessment to give feedback to school children and to compare the outcomes of different training formats. Considering these requirements, we developed an assessment of BLS skills using MiniAnne and tested the inter-rater reliability between professionals, medical students and trained school children as assessors. Fifteen professional assessors, 10 medical students and 111-trained school children (peers) assessed 1087 school children at the end of a CPR-training event using the new assessment format. Analyses of inter-rater reliability (intraclass correlation coefficient; ICC) were performed. Overall inter-rater reliability of the summative assessment was high (ICC = 0.84, 95 %-CI: 0.84 to 0.86, n = 889). The number of comparisons between peer-peer assessors (n = 303), peer-professional assessors (n = 339), and peer-student assessors (n = 191) was adequate to demonstrate high inter-rater reliability between peer- and professional-assessors (ICC: 0.76), peer- and student-assessors (ICC: 0.88) and peer- and other peer-assessors (ICC: 0.91). Systematic variation in rating of specific items was observed for three items between professional- and peer-assessors. Using this assessment and integrating peers and medical students as assessors gives the opportunity to assess hands-on skills of school children with high reliability.

  11. Functional limitations and quality of life in schizophrenia and other psychotic disorders

    OpenAIRE

    Viertiö, Satu

    2011-01-01

    There is substantial evidence of the decreased functional capacity, especially everyday functioning, of people with psychotic disorder in clinical settings, but little research about it in the general population. The aim of the present study was to provide information on the magnitude of functional capacity problems in persons with psychotic disorder compared with the general population. It estimated the prevalence and severity of limitations in vision, mobility, everyday functioning and qual...

  12. Nitrogen limitation and life history adaptation in the grasshopper "Omocestus viridulus"

    OpenAIRE

    Berner, Daniel

    2005-01-01

    The role of plant-mediated constraints to herbivore populations in terrestrial ecosystems remains relatively poorly understood. One aim of this study was therefore to explore the effects of low host plant nitrogen (N) content on herbivore performance and feeding behaviour, and thereby to evaluate the utility of the N limitation and nutrient balance concepts. The grass-feeding grasshopper Omocestus viridulus (Orthoptera: Acrididae) provided a well-suited model system as the species exhibits hi...

  13. Establishing the reliability and construct validity of the Igbo version of Screening Activity Limitation and Safety Awareness scale in persons with Hansen disease.

    Science.gov (United States)

    Ibikunle, Peter Olanrewaju; Oladipo, Samuel Ekundayo; Chukwu, Joseph Ngozi; Odole, Adesola Christiana; Okeke, Adaigwe Ifeoma

    2015-09-01

    Leprosy or Hansen's disease is an infectious disease affecting skin and peripheral nerves. The World Health Organization (WHO) Recent Report reveals Africa as having 20,599 new cases, America 36, 178, Eastern Asia 166,445, Western pacific 5,400; totally up to 232,875 new cases. Nigeria as at 2012 had 3,805 new cases. Nerve dysfunction can lead to severe impairments, such as wounds, clawing and shortening of digits, and visual impairments that are often indicated as WHO Grade 2 disabilities. The Screening Activity Limitation Safety Awareness (SALSA) scale however, was developed to-measure self-reported activity limitation in people affected by peripheral neuropathy, and has been translated into several languages world-wide, including two of the three major indigenous languages in Nigeria (i.e. Yoruba and Hausa), leaving the Igbo language yet to be translated. This resulted in the present study, in which the scale was translated into Igbo and the psychometric properties also established to help in data collection and to promote research among the Igbo speaking people living with disabilities from Hansen's disease. The research design was a cross-sectional survey, facility based with 70% RFT and 30% on MDT. Data were analysed using Cronbach's alpha and factor analyses. A quantitative exploration of participants' characteristics revealed that of the 40 respondents that participated in the study; 87.5% of them were predominantly from a rural population; 42.5% were males and 57.5% females. Their ages ranged between 15 and 64 years; 55% were uneducated; while 45% were educated. The SALSA Scale was interviewer-administered to the participants. Reliability analysis conducted on the data revealed high Cronbach's alpha co-efficient of 0.93 - 0.94 for the entire items on the scale. Firstly, most of the scale items correlated at least 0.3 with at least one other item on the scale, Secondly, the Kaiser-Meyer-Olkin measure of sampling adequacy was 0.71, Bartlett's test of

  14. Quality of School Life Scale: Means, Variances, Reliabilities, and Factor Analysis for Grades 10, 11, and 12.

    Science.gov (United States)

    Nimmer, Donald N.

    1979-01-01

    The Quality of School Life Scale (QLS) is an instrument designed to measure students' perceptions of their school experiences. Such an instrument may aid educators in evaluating students' perceptions in the three areas identified by the QSL: satisfaction, commitment to classwork, and reactions to teachers. (Author)

  15. Test-retest reliability of the Food Allergy Quality of Life Questionnaires (FAQLQ) for children, adolescents and adults

    NARCIS (Netherlands)

    van der Velde, Jantina L.; Flokstra-de Blok, Bertine M. J.; Vlieg - Boerstra, Berber J.; Oude Elberink, Joanne N. G.; Schouten, Jan P.; DunnGalvin, Audrey; Hourihane, Jonathan O'B; Duiverman, Eric J.; Dubois, Anthony E. J.

    The self-administered Food Allergy Quality of Life Questionnaire-Child Form (FAQLQ-CF), -Teenager Form (FAQLQ-TF) and -Adult Form (FAQLQ-AF) were recently developed within EuroPrevall, a multi-centred study of food allergy in Europe. The primary aim of this study was to evaluate the test-retest

  16. Test-retest reliability of the Food Allergy Quality of Life Questionnaires (FAQLQ) for children, adolescents and adults

    NARCIS (Netherlands)

    van der Velde, Jantina L.; Flokstra-de Blok, Bertine M. J.; Vlieg-Boerstra, Berber J.; Oude Elberink, Joanne N. G.; Schouten, Jan P.; DunnGalvin, Audrey; Hourihane, Jonathan O.'B.; Duiverman, Eric J.; Dubois, Anthony E. J.

    2009-01-01

    The self-administered Food Allergy Quality of Life Questionnaire-Child Form (FAQLQ-CF), -Teenager Form (FAQLQ-TF) and -Adult Form (FAQLQ-AF) were recently developed within EuroPrevall, a multi-centred study of food allergy in Europe. The primary aim of this study was to evaluate the test-retest

  17. Exploring the Limits to Photosynthetic Life in the Hyperarid Atacama (Chile) and Taklimakan (China) Deserts

    Science.gov (United States)

    Warren-Rhodes, K.; Ewing, S.; McKay, C. P.; Rhodes, K. L.

    2003-12-01

    Photosynthetic microbes inhabiting the cracks or fissures (chasmoendoliths) and undersides (hypoliths) of translucent stones function as the sole primary producers in the world's driest deserts. This poster reports on our studies of the distribution and survival of these microorganisms in the hyperarid core of the Atacama Desert--an extreme environment previously considered too dry to support photosynthetic life--and the Taklimakan Desert in China--one of the oldest and driest deserts on the Earth. In both deserts, we measured colonization rates and microclimate variables across natural precipitation gradients in order to investigate the role of moisture in the ecology and survival of hypolithic and chasmoendolithic microorganisms. Our results show 1000-fold variations in colonization rates--from 12% in the wettest portions of the Taklimakan Desert to 3000 y. At slightly wetter sites in the Atacama, Δ 14C of hypolith soils was progressively more enriched in proportion to increased MAP, with corresponding turnover times of >600 y (Δ 14C = -73 ‰ at sites with ˜5-10 mm MAP and ˜1 y Δ 14C = +12 ‰ ) as annual rainfall increased to ˜25 mm. At all sites, Δ 14C signatures of non-hypolith soils corresponded to turnover times that were longer by an order of magnitude, indicating significantly slower OC cycling by non-hypoliths. In the hyperarid core of the Atacama Desert, the prolonged lack of rainfall (decadal scales of a few millimeters) is responsible for possibly the lowest hypolithic and chasmoendolithic colonization rates observed in deserts on the Earth. Microclimate data for rock and soil surface moisture from rainfall, dew and frost suggest the particular form of moisture and its frequency may also explain observed differences in hypolithic versus chasmoendolithic colonization modes. These results hold theoretical and practical considerations for both terrestrial ecology and as analogs for possible life on Mars.

  18. A Life-cycle Approach to Improve the Sustainability of Rural Water Systems in Resource-Limited Countries

    Directory of Open Access Journals (Sweden)

    Nicholas Stacey

    2012-11-01

    Full Text Available A WHO and UNICEF joint report states that in 2008, 884 million people lacked access to potable drinking water. A life-cycle approach to develop potable water systems may improve the sustainability for such systems, however, a review of the literature shows that such an approach has primarily been used for urban systems located in resourced countries. Although urbanization is increasing globally, over 40 percent of the world’s population is currently rural with many considered poor. In this paper, we present a first step towards using life-cycle assessment to develop sustainable rural water systems in resource-limited countries while pointing out the needs. For example, while there are few differences in costs and environmental impacts for many improved rural water system options, a system that uses groundwater with community standpipes is substantially lower in cost that other alternatives with a somewhat lower environmental inventory. However, a LCA approach shows that from institutional as well as community and managerial perspectives, sustainability includes many other factors besides cost and environment that are a function of the interdependent decision process used across the life cycle of a water system by aid organizations, water user committees, and household users. These factors often present the biggest challenge to designing sustainable rural water systems for resource-limited countries.

  19. Development of Reliability Based Life Prediction Methods for Thermal and Environmental Barrier Coatings in Ceramic Matrix Composites

    Science.gov (United States)

    Shah, Ashwin

    2001-01-01

    Literature survey related to the EBC/TBC (environmental barrier coating/thermal barrier coating) fife models, failure mechanisms in EBC/TBC and the initial work plan for the proposed EBC/TBC life prediction methods development was developed as well as the finite element model for the thermal/stress analysis of the GRC-developed EBC system was prepared. Technical report for these activities is given in the subsequent sections.

  20. Equilibrium moisture content of wood at different temperature/moisture conditions in the cladding of wooden constructions and in the relation to their reliability and service life

    Directory of Open Access Journals (Sweden)

    Zdeňka Havířová

    2010-01-01

    Full Text Available One of the natural properties of wood and wood-based materials is their soaking capacity (hy­gro­sco­pi­ci­ty. The moisture content of wood and building constructions of wood and wood based materials significantly influences the service life and reliability of these constructions and buildings. The equilibrium weight moisture content of built-in wood corresponding to temperature/moisture conditions inside the cladding has therefore a decisive influence on the basic requirements placed on building constructions. The wood in wooden frame cladding changes its moisture content depending on temperature and moisture conditions of the environment it is built into. The water vapor condensation doesn’t necessarily have to occur right in the wooden framework of the cladding for the equilibrium moisture content to rise over the level permissible for the reliable function of a given construction. In spite of the fact that the common heat-technical assessment cannot be considered fully capable of detecting the effects of these factors on the functional reliability of wood-based constructions and buildings, an extension has been proposed of the present method of design an assessment of building constructions according to the ČSN 73 0540 standard regarding the interpretation of equilibrium moisture content in relation to the temperature/moisture conditions and their time behavior inside a construction.

  1. Acceptability, reliability, and validity of the Stroke and Aphasia Quality of Life Scale-39 (SAQOL-39) across languages: a systematic review.

    Science.gov (United States)

    Ahmadi, Akram; Tohidast, Seyed Abolfazl; Mansuri, Banafshe; Kamali, Mohammad; Krishnan, Gopee

    2017-09-01

    This systematic review aimed to explore the acceptability, reliability, and validity of the Stroke and Aphasia Quality of Life-39 (SAQOL-39) scale across languages. We employed a systematic search of the online databases including MEDLINE (Pubmed), Science direct, Web of science, Psychinfo, Scopus, ProQuest, Google Scholar, and Cochrane library published between 2003 and 2016. We used PRISMA guidelines for conducting and reporting this review. Subsequently, screening of the titles and abstracts, extraction of data as well as the appraisal of the quality of relevant studies were carried out. The initial search returned 8185 studies. Subsequent screening and study selection processes narrowed them to 20, needing detailed review. Forward-backward translation scheme was the preferred method for translation of the SAQOL-39 from English to other languages. Mainly, the socio-cultural and linguistic adaptations were performed in the translated versions. Most versions of the SAQOL-39 showed high test-retest reliability and internal consistency. However, several psychometric properties including the validity and responsiveness were seldom reported in these versions. The SAQOL-39 scale showed high acceptability, and reliability across the languages reviewed in this study. Future translations may additionally focus on reporting the validity and responsiveness of the instrument.

  2. Electronic versus paper-based assessment of health-related quality of life specific to HIV disease: reliability study of the PROQOL-HIV questionnaire.

    Science.gov (United States)

    Duracinsky, Martin; Lalanne, Christophe; Goujard, Cécile; Herrmann, Susan; Cheung-Lung, Christian; Brosseau, Jean-Paul; Schwartz, Yannick; Chassany, Olivier

    2014-04-25

    Electronic patient-reported outcomes (PRO) provide quick and usually reliable assessments of patients' health-related quality of life (HRQL). An electronic version of the Patient-Reported Outcomes Quality of Life-human immunodeficiency virus (PROQOL-HIV) questionnaire was developed, and its face validity and reliability were assessed using standard psychometric methods. A sample of 80 French outpatients (66% male, 52/79; mean age 46.7 years, SD 10.9) were recruited. Paper-based and electronic questionnaires were completed in a randomized crossover design (2-7 day interval). Biomedical data were collected. Questionnaire version and order effects were tested on full-scale scores in a 2-way ANOVA with patients as random effects. Test-retest reliability was evaluated using Pearson and intraclass correlation coefficients (ICC, with 95% confidence interval) for each dimension. Usability testing was carried out from patients' survey reports, specifically, general satisfaction, ease of completion, quality and clarity of user interface, and motivation to participate in follow-up PROQOL-HIV electronic assessments. Questionnaire version and administration order effects (N=59 complete cases) were not significant at the 5% level, and no interaction was found between these 2 factors (P=.94). Reliability indexes were acceptable, with Pearson correlations greater than .7 and ICCs ranging from .708 to .939; scores were not statistically different between the two versions. A total of 63 (79%) complete patients' survey reports were available, and 55% of patients (30/55) reported being satisfied and interested in electronic assessment of their HRQL in clinical follow-up. Individual ratings of PROQOL-HIV user interface (85%-100% of positive responses) confirmed user interface clarity and usability. The electronic PROQOL-HIV introduces minor modifications to the original paper-based version, following International Society for Pharmacoeconomics and Outcomes Research (ISPOR) ePRO Task

  3. Validity and reliability of the TED-QOL: a new three-item questionnaire to assess quality of life in thyroid eye disease.

    Science.gov (United States)

    Fayers, Tessa; Dolman, Peter J

    2011-12-01

    To develop and test a user-friendly questionnaire for rapidly assessing quality of life (QOL) in thyroid eye disease (TED). A three-item questionnaire, the TED-QOL, was designed and compared to the 16-item Graves Ophthalmopathy (GO)-QOL and the nine-item GO-Quality of Life Scale (QLS). 100 patients with TED were administered all three questionnaires on two occasions. Results were compared to clinical severity scores (Vision, Inflammation, Strabismus, Appearance (VISA) classification). Main outcomes were construct and criterion validity, test-retest reliability, duration, comprehension and completion rates. TED-QOL correlated strongly with the other questionnaires for corresponding items (Pearson correlation: appearance 0.71, 0.62; functioning 0.69, 0.66; overall QOL 0.53). Test-retest analysis demonstrated good reliability for all three questionnaires (intraclass correlations: TED-QOL 0.81, 0.74, 0.87; GO-QOL 0.81, 0.82; GO-QLS 0.74, 0.86, 0.67). TED-QOL was significantly faster to complete (1.6 min vs GO-QOL 3.1 min, GO-QLS 2.7 min, p<0.0001) and had a higher completion rate (100% vs GO-QOL 78%, GO-QLS 94%). There was only moderate correlation between items on all three questionnaires and VISA scores. The TED-QOL is rapid and easy to complete and analyse and has similar validity and reliability to longer questionnaires. All questionnaires showed only moderate correlation with disease severity, emphasising the discrepancy between objective and subjective assessments and the importance of measuring both.

  4. The trypanosome transcriptome is remodelled during differentiation but displays limited responsiveness within life stages

    Directory of Open Access Journals (Sweden)

    Sergeenko Tatiana

    2008-06-01

    . Conclusion While trypanosomes regulate mRNA abundance to effect the major changes accompanying differentiation, a given differentiated state appears transcriptionally inflexible. The implications of the absence of a transcriptome response in trypanosomes for both virulence and models of life cycle progression are discussed.

  5. Validity and Reliability of the MacNew Heart Disease Health-Related Quality of Life Questionnaire in Patients with Heart Failure: The Persian Version

    Directory of Open Access Journals (Sweden)

    Mohammad Abbasi

    2017-12-01

    Full Text Available Background: Heart failure due to changes in the lungs, circulation, and skeletal muscle adversely influences the quality of life. Objectives: The objective of the present study is to assess the reliability and validity of the Persian version of the MacNew in patients with heart failure. Patients and Methods: The 200 Iranian patients who referred to Shahid Beheshti hospital in Qom were recruited by convenience sampling. All the patients filled out the MacNew HRQL questionnaire, the hospital anxiety and depression scale (HADS, the Short Form- 36 and socio-demographic and clinical characteristics. The reliability of the MacNew was assessed by internal consistency and test-retest reliability. Construct validity was assessed by factor analysis, convergent validity and discriminant validity. Discriminant validity of MacNew was assessed by the known-groups approach. All analyses were done through SPSS, version 20, and level of significance was considered at P < 0.05. Results: The mean MacNew Global score was 3.6 ± 0.82. Our results demonstrated that internal consistency (α = 0.94 and reproducibility (ICC = 0.84 of the Persian version of the MacNew were confirmed. The Factor analysis confirmed three factors as the original MacNew. Convergent and divergent validity of the MacNew was confirmed by its correlation pattern with physical and mental components of the SF-36. Discriminative validity was confirmed statistically and clinically for the differences in the MacNew scores on the Global scale and each subscale between Iranian patients with and without anxiety and depression. Conclusions: The Persian version of the MacNew HRQL questionnaire can be applied as a reliable and valid tool in the clinical research for Iranian patients with heart failure.

  6. Reliability Engineering

    International Nuclear Information System (INIS)

    Lee, Sang Yong

    1992-07-01

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

  7. Life at the limits: peculiar features of lichen symbiosis related to extreme environmental factors

    Science.gov (United States)

    de Vera, J.-P.; Horneck, G.; Rettberg, P.; Ott, S.

    A lichen is a symbiotic association formed by a mycobiont (fungi), a photobiont (algae) and/or a cyanobacteria. The special symbiotic contact and interaction between the bionts in a lichen is a prerequisite for maintainance of viability for each of them during influences by harsh environmental factors. In nature parameters like UV radiation, low or high temperatures and dryness may have a destructive impact on all life functions of an organism. But with lichens the evolution has created a peculiar symbiosis which enables a wide variety of lichen species to colonize habitats where their separate bionts would not be able to survive. The results of our investigations are demonstrating these aspects (de Vera et al. 2003, 2004).We have already investigated the viability of the entire lichen thallus, the embedded spores in lichen apothecia (fruiting bodies) as well as the isolated spores and isolated photobionts after exposure to most extreme conditions caused by simulated space parameters as extreme UV radiation and vacuum. The results presented here focuse on the survival capacity of the isolated photobionts from the two lichen species Xanthoria elegans and Fulgensia bracteata which are not protected by the fungal structure of the lichen thallus. They are based on examinations using a Confocal Laser Scanning Microscopy (CLSM), analysed by modern methods of the Image Tool Program and by culture experiments. In contrast to photobionts embedded in the entire lichen thallus the isolated photobionts are much more sensitve to the extreme conditions of UV radiation and vaccum: while 50 % of the bionts in an entire lichen thallus are able to cope with simulated extreme space conditions (UV-radiation: λ quad ≥ 160nm and vacuum: p = 10-5 Pa) during an exposure time of 2 weeks, the viability of the isolated photobiont cells was already decreasing after 2 hours of exposure. All photobiont cells were inactivated after longer exposure times of about 8 hours. Further more analysis

  8. Validation of the Stroke Specific Quality of Life Scale (SS-QOL): test of reliability and validity of the Danish version (SS-QOL-DK).

    Science.gov (United States)

    Muus, Ingrid; Williams, Linda S; Ringsberg, Karin C

    2007-07-01

    To test the reliability and validity of the Danish version of the Stroke Specific Quality of Life Scale version 2.0 (SS-QOL-DK), an instrument for evaluation of health-related quality of life. A correlational study. A stroke unit that provides acute care and rehabilitation for stroke patients in Frederiksborg County, Denmark. One hundred and fifty-two stroke survivors participated; 24 of these performed test-retest. Questionnaires were sent out and returned by mail. A subsequent telephone interview assessed functional level and missing items. Test-retest was measured using Spearman's r, internal consistency was estimated using Cronbach's alpha, and evaluation of floor and ceiling values in proportion of minimum and maximum scores. Construct validity was assessed by comparing patients' scores on the SS-QOL-DK with those obtained by other test methods: Beck's Depression Index, the General Health Survey Short Form 36 (SF-36), the Barthel Index and the National Institutes of Health Stroke Scale, evaluating shared variance using coefficient of determination, r2. Comparing groups with known scores assessed known-group validity. Convergent and discriminant validity were assessed. Test-retest of SS-QOL-DK showed excellent stability, Spearman's r = 0.65-0.99. Internal consistency for all domains showed Cronbach's alpha = 0.81-0.94. Missing items rate was 1.0%. Most SS-QOL-DK domains showed moderately shared variance with similar domains of other test methods, r2 = 0.03-0.62. Groups with known differences showed statistically significant difference in scores. Item-to-scale correlation coefficients of 0.37-0.88 supported convergent validity. SS-QOL-DK is a reliable and valid instrument for measuring self-reported health-related quality of life on group level among people with mild to moderate stroke.

  9. Reliability of an e-PRO Tool of EORTC QLQ-C30 for Measurement of Health-Related Quality of Life in Patients With Breast Cancer: Prospective Randomized Trial.

    Science.gov (United States)

    Wallwiener, Markus; Matthies, Lina; Simoes, Elisabeth; Keilmann, Lucia; Hartkopf, Andreas D; Sokolov, Alexander N; Walter, Christina B; Sickenberger, Nina; Wallwiener, Stephanie; Feisst, Manuel; Gass, Paul; Fasching, Peter A; Lux, Michael P; Wallwiener, Diethelm; Taran, Florin-Andrei; Rom, Joachim; Schneeweiss, Andreas; Graf, Joachim; Brucker, Sara Y

    2017-09-14

    Breast cancer represents the most common malignant disease in women worldwide. As currently systematic palliative treatment only has a limited effect on survival rates, the concept of health-related quality of life (HRQoL) is gaining more and more importance in the therapy setting of metastatic breast cancer. One of the major patient-reported outcomes (PROs) for measuring HRQoL in patients with breast cancer is provided by the European Organization for Research and Treatment of Cancer (EORTC). Currently, paper-based surveys still predominate, as only a few reliable and validated electronic-based questionnaires are available. Facing the possibilities associated with evolving digitalization in medicine, validation of electronic versions of well-established PRO is essential in order to contribute to comprehensive and holistic oncological care and to ensure high quality in cancer research. The aim of this study was to analyze the reliability of a tablet-based measuring application for EORTC QLQ-C30 in German language in patients with adjuvant and (curative) metastatic breast cancer. Paper- and tablet-based questionnaires were completed by a total of 106 female patients with adjuvant and metastatic breast cancer recruited as part of the e-PROCOM study. All patients were required to complete the electronic- (e-PRO) and paper-based versions of the HRQoL EORTC QLQ-C30 questionnaire. A frequency analysis was performed to determine descriptive sociodemographic characteristics. Both dimensions of reliability (parallel forms reliability [Wilcoxon test] and test of internal consistency [Spearman rho and agreement rates for single items, Pearson correlation and Kendall tau for each scale]) were analyzed. High correlations were shown for both dimensions of reliability (parallel forms reliability and internal consistency) in the patient's response behavior between paper- and electronic-based questionnaires. Regarding the test of parallel forms reliability, no significant

  10. Can we determine whether physical limitations are more prevalent in the US than in countries with comparable life expectancy?

    Science.gov (United States)

    Glei, Dana A; Goldman, Noreen; Ryff, Carol D; Weinstein, Maxine

    2017-12-01

    We evaluate the variability in estimates of self-reported physical limitations by age across four nationally representative surveys in the US. We consider its implications for determining whether, as previous literature suggests, the US estimates reveal limitations at an earlier age than in three countries with similar life expectancy: England, Taiwan, and Costa Rica. Based on cross-sectional data from seven population-based surveys, we use local mean smoothing to plot self-reported limitations by age for each of four physical tasks for each survey, stratified by sex. We find substantial variation in the estimates in the US across four nationally-representative surveys. For example, one US survey suggests that American women experience a walking limitation 15 years earlier than their Costa Rican counterparts, while another US survey implies that Americans have a 4-year advantage. Differences in mode of survey may account for higher prevalence of limitations in the one survey that used a self-administered mail-in questionnaire than in the other surveys that used in-person or telephone interviews. Yet, even among US surveys that used the same mode, there is still so much variability in estimates that we cannot conclude whether Americans have better or worse function than their counterparts in the other countries. Seemingly minor differences in question wording and response categories may account for the remaining inconsistency. If minor differences in question wording can result in such extensive variation in the estimates within a given population, then lack of comparability is likely to be an even greater problem when examining results across countries that do not share the same language or culture. Despite the potential utility of self-reported physical function within a survey sample, our findings imply that absolute estimates of population-level prevalence of self-reported physical limitations are unlikely to be strictly comparable across countries-or even

  11. Utilization of Minor Actinides as a Fuel Component for Ultra-Long Life VHTR Configurations: Designs, Advantages and Limitations

    International Nuclear Information System (INIS)

    Tsvetkov, Pavel V.

    2009-01-01

    This project assessed the advantages and limitations of using minor actinides as a fuel component to achieve ultra-long life Very High Temperature Reactor (VHTR) configurations. Researchers considered and compared the capabilities of pebble-bed and prismatic core designs with advanced actinide fuels to achieve ultra-long operation without refueling. Since both core designs permit flexibility in component configuration, fuel utilization, and fuel management, it is possible to improve fissile properties of minor actinides by neutron spectrum shifting through configuration adjustments. The project studied advanced actinide fuels, which could reduce the long-term radio-toxicity and heat load of high-level waste sent to a geologic repository and enable recovery of the energy contained in spent fuel. The ultra-long core life autonomous approach may reduce the technical need for additional repositories and is capable to improve marketability of the Generation IV VHTR by allowing worldwide deployment, including remote regions and regions with limited industrial resources. Utilization of minor actinides in nuclear reactors facilitates developments of new fuel cycles towards sustainable nuclear energy scenarios.

  12. Utilization of Minor Actinides as a Fuel Component for Ultra-Long Life Bhr Configurations: Designs, Advantages and Limitations

    Energy Technology Data Exchange (ETDEWEB)

    Dr. Pavel V. Tsvetkov

    2009-05-20

    This project assessed the advantages and limitations of using minor actinides as a fuel component to achieve ultra-long life Very High Temperature Reactor (VHTR) configurations. Researchers considered and compared the capabilities of pebble-bed and prismatic core designs with advanced actinide fuels to achieve ultra-long operation without refueling. Since both core designs permit flexibility in component configuration, fuel utilization, and fuel management, it is possible to improve fissile properties of minor actinides by neutron spectrum shifting through configuration adjustments. The project studied advanced actinide fuels, which could reduce the long-term radio-toxicity and heat load of high-level waste sent to a geologic repository and enable recovery of the energy contained in spent fuel. The ultra-long core life autonomous approach may reduce the technical need for additional repositories and is capable to improve marketability of the Generation IV VHTR by allowing worldwide deployment, including remote regions and regions with limited industrial resources. Utilization of minor actinides in nuclear reactors facilitates developments of new fuel cycles towards sustainable nuclear energy scenarios.

  13. Assessments of Mechanical and Life Limiting Properties of Two Candidate Silicon Nitrides for Stirling Convertor Heater Head Applications

    Science.gov (United States)

    Choi, Sung R.; Krause, David L.

    2006-01-01

    NASA Glenn Research Center is developing advanced technology for Stirling convertors with a target of significantly improving the specific power and efficiency of the convertor and overall generator for Mars rovers and deep space missions. One specific approach to the target has been recognized as the use of appropriate high-temperature materials. As a series of ceramic material approaches in Advanced Stirling Convertor Development Program in fiscal year 2005, two commercial, structural silicon nitrides AS800 (Honeywell, Torrence, California) and SN282 (Kyocera, Vancouver, Washington) were selected and their mechanical and life limiting properties were characterized at 1050 C in air. AS800 exhibited both strength and Weibull modulus greater than SN282. A life limiting phenomenon was apparent in AS800 with a low slow crack growth parameter n = 15; whereas, a much increased resistance to slow crack growth was found in SN282 with n greater than 100. Difference in elastic modulus and thermal conductivity was negligible up to 1200 C between the two silicon nitrides. The same was true for the coefficient of thermal expansion up to 1400 C.

  14. Narcissistic Personality Disorder in Clinical Health Psychology Practice: Case Studies of Comorbid Psychological Distress and Life-Limiting Illness.

    Science.gov (United States)

    Kacel, Elizabeth L; Ennis, Nicole; Pereira, Deidre B

    2017-01-01

    Narcissistic Personality Disorder (NPD) is characterized by a persistent pattern of grandiosity, fantasies of unlimited power or importance, and the need for admiration or special treatment. Individuals with NPD may experience significant psychological distress related to interpersonal conflict and functional impairment. Research suggests core features of the disorder are associated with poor prognosis in therapy, including slow progress to behavioral change, premature patient-initiated termination, and negative therapeutic alliance. The current manuscript will explore challenges of working with NPD within the context of life-limiting illness for two psychotherapy patients seen in a behavioral health clinic at a large academic health science center. The ways in which their personality disorder affected their illness-experience shared significant overlap characterized by resistance to psychotherapeutic change, inconsistent adherence to medical recommendations, and volatile relationships with providers. In this manuscript we will (1) explore the ways in which aspects of narcissistic personality disorder impacted the patients' physical health, emotional well-being, and healthcare utilization; (2) describe psychotherapeutic methods that may be useful for optimizing psychosocial, behavioral, and physical well-being in individuals with co-morbid NPD and life-limiting disease; and (3) review conceptualizations of NPD from the DSM-5 alternative model for assessing personality function via trait domains.

  15. 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....

  16. Is Nottingham Health Profile a reliable tool to measure quality of life of Filipinos with chronic kidney diseases undergoing hemodialysis.

    Science.gov (United States)

    Chuku, Chika Lawson; Valdez, Josephine R; Ajonuma, Louis Chukwuemeka

    2010-12-01

    The quality of life (QOL) of hemodialysis patients is often compromised and many tools have been developed to assess the health-related QOL of chronic kidney disease (CKD) patients undergoing hemodialysis. However, no such tool is currently in use in the Philippines. The objective of this study is to determine if Nottingham Health Profile (NHP) can be a useful tool in the Philippines. Eighty patients undergoing hemodialysis in the dialysis unit of our hospital were enrolled for this study. Sixty-nine patients completed the study. Comparative analysis revealed significant difference in social isolation with favorable result for the Filipino patients. Other measures correlate well although with differences that were not statistically significant. NHP can be successfully applied as a standard QOL tool in the Philippines. However, it should be translated into Filipino to avoid language difficulty. NHP may be recommended for QOL determination in other developing countries.

  17. The EORTC Core Quality of Life questionnaire (QLQ-C30): validity and reliability when analysed with patients treated with palliative radiotherapy

    International Nuclear Information System (INIS)

    Kaasa, S.; Aaronson, N.

    1995-01-01

    The EORTC Core Quality of Life questionnaire (EORTC QLQ-C30) is designed to measure cancer patients' physical, psychological and social functions. The questionnaire is composed of multi-item scales and single items. 247 patients completed the EORTC QLQ-C30 before palliative radiotherapy and 181 after palliative radiotherapy. The questionnaire was well accepted with a high completion rate in the present patient population consisting of advanced cancer patients with short life expectancy. In addition, the questionnaire was found to be useful to detect the effect of palliative radiotherapy over time. The scale reliability was excellent for all scales except the role functioning scale. Excellent criterion validity was found for the emotional functioning scale where it was correlated with GHQ-20. Performance of the questionnaire was improved after the second evaluation as compared with the first. The present study shows that the EORTC-QLQ-C30 is found to be practical and valid in measuring quality of life in patients with advanced disease. (author)

  18. Impact, meaning and need for help and support: The experience of parents caring for children with disabilities, life-limiting/life-threatening illness or technology dependence.

    Science.gov (United States)

    Whiting, Mark

    2013-03-01

    Parenting a child with complex needs or disabilities is a challenging proposition. This study, which drew upon of the experiences of the parents of 34 children (in 33 families), set out to explore the themes of impact, need for help and support and meaning/sense-making as they were related by parents. Data were collected using semi-structured interviews, and an emerging theoretical framework was validated through the use of a series of mind-maps(®) which were presented to individual parents as the basis for a second round (verificational) interview. Parents were nominated into the study by health care professions who were asked to identify the subject children to one of three separate sub-groups: children with a disability; children with a life-limiting/life-threatening illness or children with a technology dependence. Comparisons were made between the three study sub-groups in order to identify areas of consistency and of inconsistency. A fourth study theme - 'battleground' emerged from entirely within the data set. Sense-making occupied a central position within the overall theoretical framework for the study and parental perception of 'battleground' presented as significant element of parental sense-making, particularly in the context of their relationships with professional staff. © The Author(s) 2012.

  19. 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

  20. The Chinese version of the Pediatric Quality of Life Inventory™ (PedsQL™) 3.0 Asthma Module: reliability and validity.

    Science.gov (United States)

    Feng, Lifen; Zhang, Yingfen; Chen, Ruoqing; Hao, Yuantao

    2011-08-07

    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. 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. 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. The Chinese version of the PedsQL™ 3.0 Asthma Module has acceptable psychometric

  1. Limitations of Routine Verification of Nasogastric Tube Insertion Using X-Ray and Auscultation: Two Case Reports of Life-Threatening Complications.

    Science.gov (United States)

    Nejo, Takahide; Oya, Soichi; Tsukasa, Tsuchiya; Yamaguchi, Naomi; Matsui, Toru

    2016-12-01

    Several bedside approaches used in combination with thoracoabdominal X-ray are widely used to avoid severe complications that have been reported during nasogastric tube management. Although confirmation by X-ray is considered the gold standard, it is not yet perfect. We present 2 cases of rare complications in which the routine verification methods could not detect all the complications related to the nasogastric tube placement. Case 1 was a 17-year-old male who presented with a brain tumor and repeatedly required nasogastric tube placement. Despite normal auscultatory and X-ray findings, the patient's condition deteriorated rapidly after resuming the enteral nutrition (EN). Computed tomography images showed the presence of hepatic portal venous gas (HPVG). Urgent upper gastrointestinal endoscopy showed esophagogastric submucosal tunneling of the tube that required an emergency open total gastrectomy. Case 2 was a 76-year-old man with long-term EN after stroke. While the last auscultatory verification was normal, he suddenly developed extensive HPVG due to gastric mucosal injury following EN, which resulted in progressive intestinal necrosis, general peritonitis, and death. These 2 cases indicated that routine verification methods consisting of auscultation and X-ray may not be completely reliable, and the awareness of the limitations of these methods should be reaffirmed because expeditious examinations and necessary interventions are critical in preventing life-threatening complications.

  2. Lived experiences of parents caring for a child with a life-limiting condition in Australia: A qualitative study.

    Science.gov (United States)

    Collins, Anna; Hennessy-Anderson, Nicole; Hosking, Sarah; Hynson, Jenny; Remedios, Cheryl; Thomas, Kristina

    2016-12-01

    Experiential studies in paediatric palliative care are needed to enable an ongoing international agenda which supports the development of responsive family supports. To provide an in-depth exploration of the prevalent lived experiences of parents who are currently providing care for a child with a life-limiting condition in Australia. Cross-sectional, prospective, qualitative study guided by an advisory group and reported according to the consolidated criteria for reporting qualitative studies. Transcripts were subjected to a thematic analysis, underpinned by an interpretative phenomenological framework. Purposively sampled parents (n = 14) recruited from a statewide paediatric hospice who self-identified as a 'primary caregiver' for one or more children and/or adolescents (⩽18 years) with a life-limiting condition. Four key themes represented the prevalent experiences of parents: (1) trapped inside the house, (2) the protector, (3) living with the shadow and (4) travelling a different pathway. They describe parents' physical and social isolation, exclusion from the workforce, pervasive grief and associated impacts to their health and well-being. Limited professional and diminished social supports resulted in full ownership of care responsibility. Yet, parents embraced their role as 'protector', reporting acquired meaning and purpose. This study builds upon the growing body of evidence available in paediatric palliative care internationally. The key themes highlight the substantial demand for both physical and emotional support beyond what is currently offered and call for the implementation of carefully planned support services and other societal initiatives which seek to alleviate the broad health impacts to caregivers. © The Author(s) 2016.

  3. Verification of the reliability and validity of a Japanese version of the Quality of Life in Childhood Epilepsy Questionnaire (QOLCE-J).

    Science.gov (United States)

    Moriguchi, Eri; Ito, Mikiko; Nagai, Toshisaburo

    2015-11-01

    A Japanese version of the Quality of Life in Childhood Epilepsy Questionnaire (QOLCE-J) was developed using international guidelines as a QOL scale for childhood epilepsy; its reliability and validity were examined, focusing on Japanese pediatric epilepsy patients applicability. A pilot test questionnaire survey was conducted; involving parents of pediatric epilepsy patients aged 4-15 undergoing outpatient treatment. 278 responses were obtained and analyzed. Internal consistency for the 16 QOLCE-J subscales, except for , was sufficient, and a high overall coefficient α was obtained. The intraclass correlation coefficient was also high, supporting the test-retest reliability of this version. Associations among the subscales, high correlations of r>0.7 were observed among , , and , representing cognitive and behavioral aspects, and among these and . In contrast, correlations among others were moderate or weaker. Furthermore, correlations of r>0.35 were observed among the subscales of the SDQ (Strength and Difficulties Questionnaire) used as an external criterion and the QOLCE-J, confirming the criterion validity of the study version. Analysis of associations between the total QOLCE-J score and pathology of epilepsy, found significant correlation with age of onset and frequency of seizures, ADL, and antiepileptics side effects' symptoms. QOLCE has mostly been used in treatment resistant pediatric patients, the influence of interictal period presently observed, like antiepileptic side effects' symptoms; suggest usefulness for pediatric patients with seizures under control. The QOLCE-J with sufficient reliability and validity may be applicable as a QOL scale for Japanese children with epilepsy. Copyright © 2015 The Japanese Society of Child Neurology. Published by Elsevier B.V. All rights reserved.

  4. Health-related quality of life in children and adolescents: Current normative data, determinants and reliability on proxy-report.

    Science.gov (United States)

    Meyer, Michael; Oberhoffer, Renate; Hock, Julia; Giegerich, Tobias; Müller, Jan

    2016-06-01

    Health-related quality of life (HrQoL) is a multidimensional concept including self-reported measures of physical and mental health. Throughout the last decades, HrQoL has become a more and more important outcome measure not only in clinical conditions. This study evaluates current HrQoL of healthy children and adolescents, determinants of HrQoL, and the agreement between self- and proxy-report. From April 2012 to July 2013, we prospectively examined 530 healthy children (13.2 ± 2.1 years, 236 girls) and their parents on their childrens HrQoL using the KINDL-R self-report questionnaire and the parent's proxy-report. Data was compared to the established reference value from 2007 and the agreement of self- and parent's proxy-report was assessed by calculation of intraclass correlation coefficient (ICC). In general, the HrQoL improved compared to references in both children's (104.5 ± 12.6 % of predicted reference value, P proxy-report (104.3 ± 12.3 % of predicted reference value, P proxy-report (ICC: .774). Only in the domains 'self-esteem' (ICC: .558) and 'Emotional well-being' (ICC: .612) the agreements were moderate. HrQoL perception has increased throughout the past 10 years and worsens with increasing age. Moreover, the parent's proxy-report of the KINDL-R questionnaire is a good supplementary method to provide additional information regarding to children's HrQoL. © 2016 Paediatrics and Child Health Division (The Royal Australasian College of Physicians).

  5. Validity, reliability, and factor analysis of Persian version of quality of life questionnaire for irritable bowel syndrome (IBS-QOL-34

    Directory of Open Access Journals (Sweden)

    Nasrine Masaeli

    2013-01-01

    Full Text Available Background: Quality of life (QOL improvement is the main objective of treating patients with irritable bowel syndrome (IBS. This study aimed to assess the validity, reliability, and factor analysis of IBS-QOL-34 questionnaire as a common transcultural instrument for Iranian IBS patients. Materials and Methods: Two hundred and forty patients with IBS (based on gastroenterologists′ diagnosis according to ROM III criteria were referred to Digestive Health Clinic in Psychosomatic Research Center have been selected in this study. Aside with IBS-QOL-34, MOS 36-item short-form health survey (SF-36 and IBS severity index (IBSSI questionnaires were completed by the cases for determination of correlation coefficients; the data were analyzed using descriptive statistics, factor analysis, Cronbach′s alpha, Pearson correlation coefficient by Statistical Package for Social Sciences (SPSS software, version 18. Results: Total reliability of the questionnaire was reported by using Cronbach′s alpha as 0.95, ranging from 0.65 to 0.90. Correlation coefficients of concurrent implementation of IBS-QOL with SF-36 and IBSSI resulted in −0.61 and 0.64, respectively. Exploratory factor analysis using varimax rotation identified eight principle components, which will determine QOL at 67% variance. Conclusion: According to the results, IBS-QOL-34 questionnaire has good psychometric properties in the research community and can be safely used as a valid tool to assess QOL of patients with IBS for healthcare and therapeutic purposes.

  6. The impact of self-perceived limitations, stigma and sense of coherence on quality of life in multiple sclerosis patients : results of a cross-sectional study

    NARCIS (Netherlands)

    Broersma, Feddrik; Oeseburg, Barth; Dijkstra, Jacob; Wynia, Klaske

    2018-01-01

    OBJECTIVE: To examine the impact of perceived limitations, stigma and sense of coherence on quality of life in multiple sclerosis patients. DESIGN: Cross-sectional survey. SETTING: Department of Neurology, University Medical Center Groningen, the Netherlands. SUBJECTS: Multiple sclerosis patients.

  7. Transition from children's to adult services for young adults with life-limiting conditions: A realist review of the literature.

    Science.gov (United States)

    Kerr, Helen; Price, Jayne; Nicholl, Honor; O'Halloran, Peter

    2017-11-01

    Improvements in care and treatment have led to more young adults with life-limiting conditions living beyond childhood, which means they must make the transition from children's to adult services. This has proved a challenging process for both young adults and service providers, with complex transition interventions interacting in unpredictable ways with local contexts. To explain how intervention processes interact with contextual factors to help transition from children's to adult services for young adults with life-limiting conditions. Systematic realist review of the literature. Literature was sourced from four electronic databases: Embase, MEDLINE, Science Direct and Cochrane Library from January 1995 to April 2016. This was supplemented with a search in Google Scholar and articles sourced from reference lists of included papers. Data were extracted using an adapted standardised data extraction tool which included identifying information related to interventions, mechanisms, contextual influences and outcomes. Two reviewers assessed the relevance of papers based on the inclusion criteria. Methodological rigor was assessed using the relevant Critical Appraisal Skills Programme tools. 78 articles were included in the review. Six interventions were identified related to an effective transition to adult services. Contextual factors include the need for children's service providers to collaborate with adult service providers to prepare an environment with knowledgeable staff and adequate resources. Mechanisms triggered by the interventions include a sense of empowerment and agency amongst all stakeholders. Early planning, collaboration between children's and adult service providers, and a focus on increasing the young adults' confidence in decision-making and engaging with adult services, are vital to a successful transition. Interventions should be tailored to their context and focused not only on organisational procedures but on equipping young adults, parents

  8. Intra- and trans-generational costs of reduced female body size caused by food limitation early in life in mites.

    Science.gov (United States)

    Walzer, Andreas; Schausberger, Peter

    2013-01-01

    Food limitation early in life may be compensated for by developmental plasticity resulting in accelerated development enhancing survival at the expense of small adult body size. However and especially for females in non-matching maternal and offspring environments, being smaller than the standard may incur considerable intra- and trans-generational costs. Here, we evaluated the costs of small female body size induced by food limitation early in life in the sexually size-dimorphic predatory mite Phytoseiulus persimilis. Females are larger than males. These predators are adapted to exploit ephemeral spider mite prey patches. The intra- and trans-generational effects of small maternal body size manifested in lower maternal survival probabilities, decreased attractiveness for males, and a reduced number and size of eggs compared to standard-sized females. The trans-generational effects of small maternal body size were sex-specific with small mothers producing small daughters but standard-sized sons. Small female body size apparently intensified the well-known costs of sexual activity because mortality of small but not standard-sized females mainly occurred shortly after mating. The disadvantages of small females in mating and egg production may be generally explained by size-associated morphological and physiological constraints. Additionally, size-assortative mate preferences of standard-sized mates may have rendered small females disproportionally unattractive mating partners. We argue that the sex-specific trans-generational effects were due to sexual size dimorphism - females are the larger sex and thus more strongly affected by maternal stress than the smaller males - and to sexually selected lower plasticity of male body size.

  9. Intra- and Trans-Generational Costs of Reduced Female Body Size Caused by Food Limitation Early in Life in Mites

    Science.gov (United States)

    Walzer, Andreas; Schausberger, Peter

    2013-01-01

    Background Food limitation early in life may be compensated for by developmental plasticity resulting in accelerated development enhancing survival at the expense of small adult body size. However and especially for females in non-matching maternal and offspring environments, being smaller than the standard may incur considerable intra- and trans-generational costs. Methodology/Principal Findings Here, we evaluated the costs of small female body size induced by food limitation early in life in the sexually size-dimorphic predatory mite Phytoseiulus persimilis. Females are larger than males. These predators are adapted to exploit ephemeral spider mite prey patches. The intra- and trans-generational effects of small maternal body size manifested in lower maternal survival probabilities, decreased attractiveness for males, and a reduced number and size of eggs compared to standard-sized females. The trans-generational effects of small maternal body size were sex-specific with small mothers producing small daughters but standard-sized sons. Conclusions/Significance Small female body size apparently intensified the well-known costs of sexual activity because mortality of small but not standard-sized females mainly occurred shortly after mating. The disadvantages of small females in mating and egg production may be generally explained by size-associated morphological and physiological constraints. Additionally, size-assortative mate preferences of standard-sized mates may have rendered small females disproportionally unattractive mating partners. We argue that the sex-specific trans-generational effects were due to sexual size dimorphism – females are the larger sex and thus more strongly affected by maternal stress than the smaller males – and to sexually selected lower plasticity of male body size. PMID:24265745

  10. Intra- and trans-generational costs of reduced female body size caused by food limitation early in life in mites.

    Directory of Open Access Journals (Sweden)

    Andreas Walzer

    Full Text Available Food limitation early in life may be compensated for by developmental plasticity resulting in accelerated development enhancing survival at the expense of small adult body size. However and especially for females in non-matching maternal and offspring environments, being smaller than the standard may incur considerable intra- and trans-generational costs.Here, we evaluated the costs of small female body size induced by food limitation early in life in the sexually size-dimorphic predatory mite Phytoseiulus persimilis. Females are larger than males. These predators are adapted to exploit ephemeral spider mite prey patches. The intra- and trans-generational effects of small maternal body size manifested in lower maternal survival probabilities, decreased attractiveness for males, and a reduced number and size of eggs compared to standard-sized females. The trans-generational effects of small maternal body size were sex-specific with small mothers producing small daughters but standard-sized sons.Small female body size apparently intensified the well-known costs of sexual activity because mortality of small but not standard-sized females mainly occurred shortly after mating. The disadvantages of small females in mating and egg production may be generally explained by size-associated morphological and physiological constraints. Additionally, size-assortative mate preferences of standard-sized mates may have rendered small females disproportionally unattractive mating partners. We argue that the sex-specific trans-generational effects were due to sexual size dimorphism - females are the larger sex and thus more strongly affected by maternal stress than the smaller males - and to sexually selected lower plasticity of male body size.

  11. 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.

  12. Hybrid PSO–SVM-based method for forecasting of the remaining useful life for aircraft engines and evaluation of its reliability

    International Nuclear Information System (INIS)

    García Nieto, P.J.; García-Gonzalo, E.; Sánchez Lasheras, F.; Cos Juez, F.J. de

    2015-01-01

    The present paper describes a hybrid PSO–SVM-based model for the prediction of the remaining useful life of aircraft engines. The proposed hybrid model combines support vector machines (SVMs), which have been successfully adopted for regression problems, with the particle swarm optimization (PSO) technique. This optimization technique involves kernel parameter setting in the SVM training procedure, which significantly influences the regression accuracy. However, its use in reliability applications has not been yet widely explored. Bearing this in mind, remaining useful life values have been predicted here by using the hybrid PSO–SVM-based model from the remaining measured parameters (input variables) for aircraft engines with success. A coefficient of determination equal to 0.9034 was obtained when this hybrid PSO–RBF–SVM-based model was applied to experimental data. The agreement of this model with experimental data confirmed its good performance. One of the main advantages of this predictive model is that it does not require information about the previous operation states of the engine. Finally, the main conclusions of this study are exposed. - Highlights: • A hybrid PSO–SVM-based model is built as a predictive model of the RUL values for aircraft engines. • The remaining physical–chemical variables in this process are studied in depth. • The obtained regression accuracy of our method is about 95%. • The results show that PSO–SVM-based model can assist in the diagnosis of the RUL values with accuracy

  13. Manual dexterity in hereditary motor and sensory neuropathy type 1a: severity of limitations and feasibility and reliability of two assessment instruments

    NARCIS (Netherlands)

    Videler, Annemieke J.; Beelen, Anita; van Schaik, Ivo N.; de Visser, Marianne; Nollet, Frans

    2008-01-01

    OBJECTIVE: To assess the prevalence and significance of impaired manual dexterity in hereditary motor and sensory neuropathy type 1a (HMSN 1a), with the Sollerman hand function and the Functional Dexterity test, and compare the reliability and agreement of the tests. DESIGN: Descriptive

  14. Reliability and validity of Thai versions of the MOS-HIV and SF-12 quality of life questionnaires in people living with HIV/AIDS

    Directory of Open Access Journals (Sweden)

    Kemerer Verne F

    2011-03-01

    Full Text Available Abstract Background/Aim As Thai people living with HIV/AIDS gain increasing access to antiretroviral (ARV therapy, it is important to evaluate the impact this has not only on clinical outcomes, but also on patients' functional status and well-being. In this study, we translated, culturally adapted and tested the reliability and validity of two widely-used health-related quality of life questionnaires - the MOS-HIV Health Survey and the SF-12 - in people living with HIV/AIDS in Northern Thailand. Methods: Questionnaires were administered to 100 patients at community hospital outpatient ARV clinics in northern Thailand. Reliability was estimated using Cronbach's alpha, while evidence for validity was tested using known-groups comparison based on CD4 group, symptom distress score, bed days and days of reduced activity in the past three months. Results Patients' median age was 36, with 58% female, 58% working as laborers, and 60% completing at least primary education. Median CD4 count was 218 cells/mm3. There were no missing data. For the MOS-HIV and SF-12, mean physical summary scores were 53.1 and 49.0 respectively; mean mental summary scores were 53.4 and 45.6, respectively. Internal consistency coefficients were >0.7 for all but one scale, the PF scale (0.67. As hypothesized, scores were slightly to moderately correlated with CD4 count, symptom score, number of days in bed or with reduced activity. Correlations were higher with physical health scores than with mental health scales. The MOS-HIV discriminated clinical known groups slightly better than the SF-12. Conclusion Both the MOS-HIV and the shorter SF-12 were successfully adapted for people with HIV/AIDS in Northern Thailand, and showed encouraging evidence for reliability and validity. These patient reported questionnaires could be valuable tools in evaluating therapeutic interventions and other innovations in health and social services, and to estimate health needs and population

  15. Simulated Seasonal Photoperiods and Fluctuating Temperatures Have Limited Effects on Blood Feeding and Life History in Aedes triseriatus (Diptera: Culicidae).

    Science.gov (United States)

    Westby, K M; Juliano, S A

    2015-09-01

    Biotic and abiotic factors change seasonally and impact life history in temperate-zone ectotherms. Temperature and photoperiod are factors that change in predictable ways. Most studies testing for effects of temperature on vectors use constant temperatures and ignore potential correlated effects of photoperiod. In two experiments, we tested for effects of larval rearing environments creating ecologically relevant temperatures and photoperiods simulating early and late season conditions (June and August), or constant temperatures (cool and warm) with the June or August photoperiods, respectively. We determined effects on survivorship, development, size, and a composite performance index in a temperate-zone population of Aedes triseriatus (Say). We followed cohorts of resulting females, all held under the same environmental conditions, to assess carry-over effects of rearing conditions for larvae on longevity, blood feeding, and egg production. Larval survivorship was affected by treatment in one experiment. Development time was greater in the June and cool treatments, but the constant and fluctuating temperatures did not differ. Significantly larger mosquitoes were produced in fluctuating versus constant temperature treatments. There were no significant treatment effects on the composite performance index. Adult female longevity was lower after rearing at constant versus fluctuating temperature, but there was no difference between June and August, nor did size affect longevity. There was no effect of treatments on blood feeding and a limited effect on egg production. We conclude that seasonal temperatures and photoperiods during development have limited effects on this population of A. triseriatus and find little evidence of strong effects of fluctuating versus constant temperatures. © The Authors 2015. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  16. 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

  17. Definition of Terms Used in Limitation of Treatment and Providing Palliative Care at the End of Life: The Indian Council of Medical Research Commission Report

    Science.gov (United States)

    Salins, Naveen; Gursahani, Roop; Mathur, Roli; Iyer, Shivakumar; Macaden, Stanley; Simha, Nagesh; Mani, Raj Kumar; Rajagopal, M. R.

    2018-01-01

    Background: Indian hospitals, in general, lack policies on the limitation of inappropriate life-sustaining interventions at the end of life. To facilitate discussion, preparation of guidelines and framing of laws, terminologies relating to the treatment limitation, and providing palliative care at the end-of-life care (EOLC) need to be defined and brought up to date. Methodology: This consensus document on terminologies and definitions of terminologies was prepared under the aegis of the Indian Council of Medical Research. The consensus statement was created using Nominal Group and Delphi Method. Results: Twenty-five definitions related to the limitations of treatment and providing palliative care at the end of life were created by reviewing existing international documents and suitably modifying it to the Indian sociocultural context by achieving national consensus. Twenty-five terminologies defined within the scope of this document are (1) terminal illness, (2) actively dying, (3) life-sustaining treatment, (4) potentially inappropriate treatment, (5) cardiopulmonary resuscitation (CPR), (6) do not attempt CPR, (7) withholding life-sustaining treatment, (8) withdrawing life-sustaining treatment, (9) euthanasia (10) active shortening of the dying process, (11) physician-assisted suicide, (12) palliative care, (13) EOLC, (14) palliative sedation, (15) double effect, (16) death, (17) best interests, (18) health-care decision-making capacity, (19) shared decision-making, (20) advance directives, (21) surrogates, (22) autonomy, (23) beneficence, (24) nonmaleficence, and (25) justice.

  18. Informing social work practice through research with parent caregivers of a child with a life-limiting illness.

    Science.gov (United States)

    Cadell, Susan; Kennedy, Kimberly; Hemsworth, David

    2012-01-01

    Pediatric palliative care is an evolving field of practice in social work. As such, research plays a critical role in informing best social work practices in this area. For parents, caring for a child with a life-limiting illness (LLI) is a stressful experience that compounds the usual challenges of parenting. The negative aspects of caring for a child with an LLI are well documented. In the face of such adversity, parent caregivers can also experience positive changes caring for children with even the most serious conditions. This article presents results from a research study of posttraumatic growth in parents who are caring for a child with a LLI. Using mixed methods, two overarching themes were prominent in both the quantitative and qualitative data. The first describes stress related to financial burden associated with caregiving. The second theme concerns the posttraumatic growth experienced by the parent caregivers. The quantitative and qualitative data have been woven together to underscore issues and parental perspectives related to these two themes. This provides a unique and important platform for parent caregivers' experiences that can inform the work of social workers and other pediatric palliative care professionals.

  19. Life course persistent and adolescence limited conduct disorder in a nationally representative US sample: prevalence, predictors, and outcomes.

    Science.gov (United States)

    Moore, Ashlee A; Silberg, Judy L; Roberson-Nay, Roxann; Mezuk, Briana

    2017-04-01

    The course of conduct disorder (CD) is heterogeneous. Moffitt proposed the heuristic of life course persistent (LCP) and adolescence limited (AL) to differentiate etiologically distinct forms of antisocial behavior (AB), each with distinct predictors and consequences, although a few studies have assessed this demarcation within the context of CD. The objective of this study was to apply Moffitt's taxonomy in a nationally representative US sample to investigate the prevalence, predictors, and outcomes of LCP and AL CD. Data come from the Collaborative Psychiatric Epidemiology Studies, a set of population-based nationally representative cross-sectional surveys (N = 20,130). Predictors included harsh discipline, maternal and paternal closeness, poverty in childhood, history of learning disability, parental deviance, and nativity. Outcomes included substance use, employment status, education attainment, marital status, income level, and self-rated mental and physical health. The prevalence of LCP and AL CD was 0.5 and 4.6%, respectively, for females, and 1.9 and 5.1%, respectively, for males. Low childhood SES [Odds Ratio (OR) = 3.49], lack of maternal closeness (OR = 2.50), and history of harsh discipline (OR = 2.17) increased odds of LCP group membership. The LCP group had higher odds of developing substance use disorders (OR = 2.00) relative to AL. LCP CD is more strongly influenced by childhood environment and confers increased odds for substance use problems in adulthood relative to AL CD.

  20. 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...

  1. A relational understanding of sibling experiences of children with rare life-limiting conditions: findings from a qualitative study.

    Science.gov (United States)

    Malcolm, Cari; Gibson, Faith; Adams, Sally; Anderson, Gillian; Forbat, Liz

    2014-09-01

    Mucopolysaccharidoses (MPS) and Batten disease are rare life-limiting conditions (LLCs) characterised by progressive and permanent physical and cognitive decline. The impact of such conditions on families, and notably on siblings, has not yet been described or documented. This paper presents data from a UK-wide study that sought to understand the family experience of supporting a child with the rare degenerative LLCs of MPS and Batten disease. The aim of this paper is to report sibling experiences related to these rare degenerative and progressive conditions, in order to inform the future development of supportive interventions. Eight siblings of children with MPS (n = 7) and Batten Disease (n = 1) participated in semi-structured qualitative interviews. A card sort technique was utilised to support and engage the children. Siblings are clearly impacted emotionally, pragmatically and relationally by the ill health of another child in the family. The data indicate four key themes which demonstrate impacts on siblings: perceptions of the condition and its symptoms, impact on daily life, emotional consequences and ways of coping. Siblings often had considerable knowledge of the condition and took on important roles in symptom management. However, these experiences were in the context of managing relationships within the family (often protecting parents from an awareness of how much they knew) and relationships at school (including distraction from learning and being bullied by peers). The data highlight how sibling experiences are generated through a combination of negative disability discourses and support through peers and family members. The data indicate how these features shift as a consequence of witnessing the advancement of their brother's or sister's condition and the emotional sequelae of disease progression. Exploration of siblings' experiences of living with such rare progressive and degenerative LLCs suggest the focus of interventions to support this

  2. Reliability, construct and criterion validity of the KIDSCREEN-10 score: a short measure for children and adolescents’ well-being and health-related quality of life

    Science.gov (United States)

    Erhart, Michael; Rajmil, Luis; Herdman, Michael; Auquier, Pascal; Bruil, Jeanet; Power, Mick; Duer, Wolfgang; Abel, Thomas; Czemy, Ladislav; Mazur, Joanna; Czimbalmos, Agnes; Tountas, Yannis; Hagquist, Curt; Kilroe, Jean

    2010-01-01

    Background To assess the criterion and construct validity of the KIDSCREEN-10 well-being and health-related quality of life (HRQoL) score, a short version of the KIDSCREEN-52 and KIDSCREEN-27 instruments. Methods The child self-report and parent report versions of the KIDSCREEN-10 were tested in a sample of 22,830 European children and adolescents aged 8–18 and their parents (n = 16,237). Correlation with the KIDSCREEN-52 and associations with other generic HRQoL measures, physical and mental health, and socioeconomic status were examined. Score differences by age, gender, and country were investigated. Results Correlations between the 10-item KIDSCREEN score and KIDSCREEN-52 scales ranged from r = 0.24 to 0.72 (r = 0.27–0.72) for the self-report version (proxy-report version). Coefficients below r = 0.5 were observed for the KIDSCREEN-52 dimensions Financial Resources and Being Bullied only. Cronbach alpha was 0.82 (0.78), test–retest reliability was ICC = 0.70 (0.67) for the self- (proxy-)report version. Correlations between other children self-completed HRQoL questionnaires and KIDSCREEN-10 ranged from r = 0.43 to r = 0.63 for the KIDSCREEN children self-report and r = 0.22–0.40 for the KIDSCREEN parent proxy report. Known group differences in HRQoL between physically/mentally healthy and ill children were observed in the KIDSCREEN-10 self and proxy scores. Associations with self-reported psychosomatic complaints were r = −0.52 (−0.36) for the KIDSCREEN-10 self-report (proxy-report). Statistically significant differences in KIDSCREEN-10 self and proxy scores were found by socioeconomic status, age, and gender. Conclusions Our results indicate that the KIDSCREEN-10 provides a valid measure of a general HRQoL factor in children and adolescents, but the instrument does not represent well most of the single dimensions of the original KIDSCREEN-52. Test–retest reliability was slightly below a priori defined thresholds. PMID:20668950

  3. Children with life-limiting conditions in paediatric intensive care units: a national cohort, data linkage study.

    Science.gov (United States)

    Fraser, Lorna K; Parslow, Roger

    2017-07-13

    To determine how many children are admitted to paediatric intensive care unit (PICU) with life-limiting conditions (LLCs) and their outcomes. National cohort, data-linkage study. PICUs in England. Children admitted to a UK PICU (1 January 2004 and 31 March 2015) were identified in the Paediatric Intensive Care Audit Network dataset. Linkage to hospital episodes statistics enabled identification of children with a LLC using an International Classification of Diseases (ICD10) code list. Random-effects logistic regression was undertaken to assess risk of death in PICU. Flexible parametric survival modelling was used to assess survival in the year after discharge. Overall, 57.6% (n=89 127) of PICU admissions and 72.90% (n=4821) of deaths in PICU were for an individual with a LLC.The crude mortality rate in PICU was 5.4% for those with a LLC and 2.7% of those without a LLC. In the fully adjusted model, children with a LLC were 75% more likely than those without a LLC to die in PICU (OR 1.75 (95% CI 1.64 to 1.87)).Although overall survival to 1 year postdischarge was 96%, children with a LLC were 2.5 times more likely to die in that year than children without a LLC (OR 2.59 (95% CI 2.47 to 2.71)). Children with a LLC accounted for a large proportion of the PICU population. There is an opportunity to integrate specialist paediatric palliative care services with paediatric critical care to enable choice around place of care for these children and families. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

  4. Limited Engagements? Women’s and Men’s Work/Volunteer Time in the Encore Life Course Stage

    Science.gov (United States)

    Moen, Phyllis; Flood, Sarah

    2013-01-01

    Americans are living healthier and longer lives, but the shifting age distribution is straining existing and projected social welfare protections for older adults (e.g., Social Security, Medicare). One solution is to delay retirement. Another is an alternative to “total leisure” retirement -- an “encore” stage of paid or unpaid engagement coming after career jobs but before infirmities associated with old age. We draw on gendered life-course themes together with data from the American Time Use Survey (2003–2009) to examine the real time American men and women ages 50–75 apportion to paid work and unpaid volunteer work on an average day, as well as factors predicting their time allocations. We find that while full-time employment declines after the 50s, many Americans allot time to more limited engagements – working part time, being self-employed, volunteering, helping out – through and even beyond their 60s. Caring for a child or infirm adult reduces the odds of paid work but not volunteering. While time working for pay declines with age (though more slowly for men than women), time volunteering does not. Older men and women in poor health, without a college degree, with a disability or SSI income are the least likely to be publicly engaged. This social patterning illustrates that while the ideal of an encore of paid or unpaid voluntary, flexible, and meaningful engagement is an emerging reality for some, it appears less attainable for others. This suggests the importance of organizational and public policy innovations offering all Americans a range of encore opportunities. PMID:24273348

  5. Reliability evaluation programmable logic devices

    International Nuclear Information System (INIS)

    Srivani, L.; Murali, N.; Thirugnana Murthy, D.; Satya Murty, S.A.V.

    2014-01-01

    Programmable Logic Devices (PLD) are widely used as basic building modules in high integrity systems, considering their robust features such as gate density, performance, speed etc. PLDs are used to implement digital design such as bus interface logic, control logic, sequencing logic, glue logic etc. Due to semiconductor evolution, new PLDs with state-of-the-art features are arriving to the market. Since these devices are reliable as per the manufacturer's specification, they were used in the design of safety systems. But due to their reduced market life, the availability of performance data is limited. So evaluating the PLD before deploying in a safety system is very important. This paper presents a survey on the use of PLDs in the nuclear domain and the steps involved in the evaluation of PLD using Quantitative Accelerated Life Testing. (author)

  6. The practice of hope: a longitudinal, multi-perspective qualitative study among South Asian Sikhs and Muslims with life-limiting illness in Scotland.

    Science.gov (United States)

    Kristiansen, Maria; Irshad, Tasneem; Worth, Allison; Bhopal, Raj; Lawton, Julia; Sheikh, Aziz

    2014-02-01

    We explored the role of faith and religious identities in shaping end of life experiences in South Asian Muslims and Sikhs with life-limiting illnesses. Secondary analysis of data from a longitudinal, multi-perspective qualitative study of the experience of life-limiting illness and access to palliative care services among South Asian Sikhs and Muslims in Scotland. Up to three semi-structured interviews were conducted with 25 participants, 15 family members and 20 health care professionals over a period of 18 months. Analysis was informed by Mattingly's theory on hope. Hope emerged as a central construct in the accounts of illness constructed by the participants as they struggled to make sense of and uphold a meaningful life. Clinical encounters and, for some, religious beliefs served as sources of hope for participants. Hope unfolded as an active process that enabled them to live with the personal and in particular the social ramifications of their illness. Changing images of hope were formulated and reflected as illness progressed or treatments failed. These ranged from hoping for cure, prolonged life, the regaining of lost capabilities needed to fulfil social roles, or at times death when suffering and the consequences for the family became too hard to bear. For those suffering from a life-limiting illness, sustaining hope is a complex challenge. The social character of hope is evident as it focuses on envisioning a life that is worth living, not only for oneself, but most importantly for social relations. Continuity in care at the end of life and a holistic approach is important in order to enable patients to articulate complex and changing notions of hope that at times are silenced within families, and for patients to feel confident in discussing the possible role of religious beliefs in shaping personal notions of hope.

  7. How does organic matter occurrence set limit onto the use of Ce anomaly as a reliable proxy of redox conditions in shallow groundwaters?

    Science.gov (United States)

    Dia, A.; Gruau, G.; Davranche, M.; Vidy, A.; Henin, O.; Petitjean, P.; Le Coz-Bouhnik, M.

    2003-04-01

    This study is dedicated to the effects of organic matter on the hydrochemistry of Rare Earth Elements (REE) and the ability of using the Ce anomaly as a reliable proxy of redox conditions in surface waters when organic matter occurs. The data include a : i) two-year survey of SREE and Ce anomalies in organic-rich waters recovered from a catchment located in Brittany (western Europe) and (ii) experimental incubation of organic soils from this catchment set under controlled conditions, as well as, (iii) a REE speciation calculation in both the natural organic-rich waters from the wetlands and the experimental solutions. Field and experimental data appear to be extremely coherent, displaying good correlation between the SREE, the Dissolved Organic Carbon (DOC) contents and the redox state. The field data show a strong increase of the SREE and DOC concentrations in soil waters when the environment becomes more reducing. The onset of DOC and SREE contents is seen to be in phase with the increase of dissolved Fe and Mn. The role of Fe-, Mn-oxyhydroxides is confirmed by the experimental data as the maximum of DOC and SREE content is reached when Fe2+ reaches a maximum in the soil solution, suggesting that reductive dissolution of Fe, Mn-oxyhydroxides happens. Despite the strong redox changes and the known redox sensitive behaviour of Ce as compared to other REE, none Ce anomaly variation is observed during either, the experimental procedure, or the field survey through time. Speciation calculations were performed showing that in both such pH range and moderately oxidizing waters in DOC-rich waters, REE should have an organic speciation. Such an organic speciation prevents the formation of Ce(IV) and therefore the development of any Ce anomaly. However, since the studied waters are highly oxidizing (high nitrate contents), the nitrates impose the redox formation of Ce(IV) and a Ce anomaly should appear. Therefore, Ce(IV) is not formed in these waters either because (i) the

  8. Human reliability

    International Nuclear Information System (INIS)

    Embrey, D.E.

    1987-01-01

    Concepts and techniques of human reliability have been developed and are used mostly in probabilistic risk assessment. For this, the major application of human reliability assessment has been to identify the human errors which have a significant effect on the overall safety of the system and to quantify the probability of their occurrence. Some of the major issues within human reliability studies are reviewed and it is shown how these are applied to the assessment of human failures in systems. This is done under the following headings; models of human performance used in human reliability assessment, the nature of human error, classification of errors in man-machine systems, practical aspects, human reliability modelling in complex situations, quantification and examination of human reliability, judgement based approaches, holistic techniques and decision analytic approaches. (UK)

  9. 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...

  10. Limited post-chemotherapy retroperitoneal resection of residual tumour in non-seminomatous testicular cancer: complications, outcome and quality of life

    DEFF Research Database (Denmark)

    Schmidt, Anna Hartmann; Høyer, Morten; Jensen, Bent Frode Skov

    2018-01-01

    , complications, working ability and quality of life (QOL) following a limited surgical procedure performed to resect residual masses in non-seminomatous testicular cancer patients after chemotherapy. MATERIAL AND METHODS: A consecutive patient cohort of 109 patients having surgery between 1993 and 2013...

  11. New limit on the half-life of 78Kr with respect to the 2K(2ν)-capture decay mode

    International Nuclear Information System (INIS)

    Gavriljuk, Ju.M.; Kuzminov, V.V.; Osetrova, N.Ya.; Ratkevich, S.S.

    2000-01-01

    The features of data accumulated for 1817 h in an experimental search for the 2K(2ν)-capture mode of 78 Kr decay are discussed. A new limit on the half-life for this decay is found: T 1sol2 ≥ 2.3 x 10 20 yr (at a 90% C.L.)

  12. NASA Applications and Lessons Learned in Reliability Engineering

    Science.gov (United States)

    Safie, Fayssal M.; Fuller, Raymond P.

    2011-01-01

    Since the Shuttle Challenger accident in 1986, communities across NASA have been developing and extensively using quantitative reliability and risk assessment methods in their decision making process. This paper discusses several reliability engineering applications that NASA has used over the year to support the design, development, and operation of critical space flight hardware. Specifically, the paper discusses several reliability engineering applications used by NASA in areas such as risk management, inspection policies, components upgrades, reliability growth, integrated failure analysis, and physics based probabilistic engineering analysis. In each of these areas, the paper provides a brief discussion of a case study to demonstrate the value added and the criticality of reliability engineering in supporting NASA project and program decisions to fly safely. Examples of these case studies discussed are reliability based life limit extension of Shuttle Space Main Engine (SSME) hardware, Reliability based inspection policies for Auxiliary Power Unit (APU) turbine disc, probabilistic structural engineering analysis for reliability prediction of the SSME alternate turbo-pump development, impact of ET foam reliability on the Space Shuttle System risk, and reliability based Space Shuttle upgrade for safety. Special attention is given in this paper to the physics based probabilistic engineering analysis applications and their critical role in evaluating the reliability of NASA development hardware including their potential use in a research and technology development environment.

  13. Non-Destructive Assessment of Concrete Structures Reliability and Limits of Single and Combined Techniques State-of-the-Art Report of the RILEM Technical Committee 207-INR

    CERN Document Server

    2012-01-01

    This book gives information on non destructive techniques for assessment of concrete structures. It synthesizes the best of international knowledge about what techniques can be used for assessing material properties (strength) and structural properties (geometry, defects...). It describes how the techniques can be used so as to answer a series of usual questions, highlighting their capabilities and limits, and providing advices for a better use of techniques. It also focuses on possible combinations of techniques so as to improve the assessment. It is based on many illustrative examples and give in each case references to standards and guidelines.

  14. Healthcare users' experiences of communicating with healthcare professionals about children who have life-limiting conditions: a qualitative systematic review protocol.

    Science.gov (United States)

    Ekberg, Stuart; Bradford, Natalie; Herbert, Anthony; Danby, Susan; Yates, Patsy

    2015-11-01

    The objective of this review is to identify and synthesize the best international qualitative evidence on healthcare users' experiences of communication with healthcare professionals about children who have life-limiting conditions. For the purposes of this review, "healthcare users" will be taken to include children who have life-limiting conditions and their families. The question to be addressed is:What are healthcare users' experiences of communicating with healthcare professionals about children who have life-limiting conditions? The prospect of the death of a child from an incurable medical condition is harrowing, yet finding a way to discuss this prospect is crucial to maximize the quality of life for such children and their families. High-quality communication is well recognized as a core skill health care professionals need to maximize the quality of care they provide. This skill is valued by service users, who consistently rate it as one of the highest priorities for the care they receive. Evidence suggests, however, that healthcare professionals can feel ill-equipped or uncomfortable communicating with and about such children. Therefore, it is important to understand what represents high-quality communication and what is involved in accomplishing this within pediatric palliative care.In recent decades there has been an increased focus on providing palliative care for children who have life-limiting conditions. These are conditions for which no cure is available and for which the probable outcome is premature death. Palliative care may also be appropriate for children who have life-threatening conditions; these are conditions where there is not only a high probability of premature death but also a chance of long-term survival into adulthood Although pediatric palliative care is underpinned by the same philosophy as adult palliative care, children who have life-limiting conditions and their families have particular needs that distinguish them from users of

  15. Psychometric properties of the 25-item Work Limitations Questionnaire in Japan: factor structure, validity, and reliability in information and communication technology company employees.

    Science.gov (United States)

    Kono, Yuko; Matsushima, Eisuke; Uji, Masayo

    2014-02-01

    The 25-item Work Limitations Questionnaire (WLQ-25) measures presenteeism but has not been sufficiently validated in a Japanese population. A total of 451 employees from four information technology companies in Tokyo completed the WLQ-25 and questionnaires of other variables on two occasions, 2 weeks apart. The WLQ-25 yielded a two-factor structure: Cognitive Demand and Physical Demand. These subscales showed good internal consistency, and both were associated with adverse working conditions, greater perceived job strain, lower skill use, poorer workplace social support, and less satisfactory psychological adjustment. Intraclass correlation coefficients of the two WLQ-25 subscales between time 1 and time 2 were 0.78 and 0.55, respectively. This study suggests acceptable psychometric properties of the WLQ-25 in Japan.

  16. Accelerated life testing of spacecraft subsystems

    Science.gov (United States)

    Wiksten, D.; Swanson, J.

    1972-01-01

    The rationale and requirements for conducting accelerated life tests on electronic subsystems of spacecraft are presented. A method for applying data on the reliability and temperature sensitivity of the parts contained in a sybsystem to the selection of accelerated life test parameters is described. Additional considerations affecting the formulation of test requirements are identified, and practical limitations of accelerated aging are described.

  17. The Cambridge Otology Quality of Life Questionnaire: an otology-specific patient-recorded outcome measure. A paper describing the instrument design and a report of preliminary reliability and validity.

    Science.gov (United States)

    Martin, T P C; Moualed, D; Paul, A; Ronan, N; Tysome, J R; Donnelly, N P; Cook, R; Axon, P R

    2015-04-01

    The Cambridge Otology Quality of Life Questionnaire (COQOL) is a patient-recorded outcome measurement (PROM) designed to quantify the quality of life of patients attending otology clinics. Item-reduction model. A systematically designed long-form version (74 items) was tested with patient focus groups before being presented to adult otology patients (n. 137). Preliminary item analysis tested reliability, reducing the COQOL to 24 questions. This was then presented in conjunction with the SF-36 (V1) questionnaire to a total of 203 patients. Subsequently, these were re-presented at T + 3 months, and patients recorded whether they felt their condition had improved, deteriorated or remained the same. Non-responders were contacted by post. A correlation between COQOL scores and patient perception of change was examined to analyse content validity. Teaching hospital and university psychology department. Adult patients attending otology clinics with a wide range of otological conditions. Item reliability measured by item–total correlation, internal consistency and test– retest reliability. Validity measured by correlation between COQOL scores and patient-reported symptom change. Reliability: the COQOL showed excellent internal consistency at both initial presentation (a = 0.90) and 3 months later (a = 0.93). Validity: One-way analysis of variance showed a significant difference between groups reporting change and those reporting no change in quality of life (F(2, 80) = 5.866, P < 0.01). The COQOL is the first otology-specific PROM. Initial studies demonstrate excellent reliability and encouraging preliminary criterion validity: further studies will allow a deeper validation of the instrument.

  18. Columbus safety and reliability

    Science.gov (United States)

    Longhurst, F.; Wessels, H.

    1988-10-01

    Analyses carried out to ensure Columbus reliability, availability, and maintainability, and operational and design safety are summarized. Failure modes/effects/criticality is the main qualitative tool used. The main aspects studied are fault tolerance, hazard consequence control, risk minimization, human error effects, restorability, and safe-life design.

  19. Reliability based structural design

    NARCIS (Netherlands)

    Vrouwenvelder, A.C.W.M.

    2014-01-01

    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. Limites e possibilidades da identificação de risco de autismo no primeiro ano de vida Limits and possibilities of identifying autism within the first year of life

    Directory of Open Access Journals (Sweden)

    Mariana Luisa Garcia

    2011-01-01

    Full Text Available Identificar risco de autismo no primeiro ano de vida possibilita intervir precocemente para um prognóstico mais favorável em crianças com autismo. O objetivo deste artigo é discutir limites e possibilidades metodológicas que viabilizem a identificação de sinais de risco de autismo entre 0-12 meses. A metodologia empregada em 24 estudos (retrospectivos e prospectivos sobre identificação de sinais precoces e seus resultados foram analisados. Verificou-se que os limites da identificação de risco de autismo no primeiro ano parecem residir na buscar por categorias comportamentais discretas e que as possibilidades podem residir em analisar categorias de interação e de ordem afetiva.Identifying signs of autism in the first year of life is justified by early intervention and better prognostic. This article aims at discussing methodological limits and possibilities of identifying risk of autism at 0-12 months. Methodology from 24 retrospective and prospective early signs studies and their outcomes were analyzed. Limits of identifying risk of autism in the 1st year of life lies in observing discrete behavioral categories, and possibilities seem to lie in analyzing interactional and affective categories.

  1. Design reliability engineering

    International Nuclear Information System (INIS)

    Buden, D.; Hunt, R.N.M.

    1989-01-01

    Improved design techniques are needed to achieve high reliability at minimum cost. This is especially true of space systems where lifetimes of many years without maintenance are needed and severe mass limitations exist. Reliability must be designed into these systems from the start. Techniques are now being explored to structure a formal design process that will be more complete and less expensive. The intent is to integrate the best features of design, reliability analysis, and expert systems to design highly reliable systems to meet stressing needs. Taken into account are the large uncertainties that exist in materials, design models, and fabrication techniques. Expert systems are a convenient method to integrate into the design process a complete definition of all elements that should be considered and an opportunity to integrate the design process with reliability, safety, test engineering, maintenance and operator training. 1 fig

  2. A computer program for calculation of parameters necessary for the computation of reliable pair distribution functions of non-crystalline materials from limited diffraction data. II

    International Nuclear Information System (INIS)

    Hansen, F.Y.

    1978-01-01

    The pair distribution function of non-crystalline materials may be obtained by a Fourier transform of the structure factor as calculated in part I of this series. The structure factor is often limited in the sense that it shows significant oscillations at the maximal wave vector transfers obtainable. The Fourier transform of such functions, therefore, introduces truncation errors in the transformed function. With this program a parametrization of the small distance part of the pair distribution function is obtained according to a method described which enables one to eliminate truncation error from the final pair distribution function. It is based on a least squares fit calculation of the small distance part of the pair distribution function obtained by a direct transform of the experimental structure factor and a model pair distribution function obtained from a model structure factor truncated at the same wave vector transfers as the experimental factor. The storage requirement depends on the number of structure factor data and the number of peaks used to resolve the small distance part of the pair distribution function. In the present set-up storage requirement is set to 15083 words, which is estimated to be satisfactory for a large number of cases. (Auth.)

  3. 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

  4. Limits of reliability of optical properties of commercial glass in Mexico, a comparative analysis with experimental results; Limites de confiabilidad de propiedades opticas de vidrios comerciales en mexico, analisis comparativo con resultados experimentales

    Energy Technology Data Exchange (ETDEWEB)

    Barrios Rodriguez, Pilar; Dorantes Rodriguez, Ruben J. [Universidad Autonoma Metropolitana Azcapotzalco, Mexico, D.F. (Mexico)

    2000-07-01

    The heat transfer through the buildings has been increased by the intensive use of glass in the building's covering; this situation has demanded more electrical energy for compensate the heat's gain or loss. Energy use in buildings is responsible for some 50% of CO{sub 2} emissions in many countries, so it's necessary a building's thermal design for a rational use of energy. The glass is an important material in the building's encircling, so it's essential to count on precise values of the glass's properties for design building's covering. Experimental evaluation on optical properties in some building's glasses to compare the experimental values with manufacturer's reported values inside tolerance limits. [Spanish] La ganancia de calor solar al interior de las edificaciones se ha visto incrementada por la tendencia actual en el uso intensivo y extensivo del vidrio en la envolvente, lo que ha aumentado la necesidad del uso de energia electrica para compensar con climatizacion artificial las ganancias y/o perdidas termicas en los espacios interiores de las edificaciones. El gasto energetico en edificios es responsable de cerca del 50% de emision de CO{sub 2} en varios paises, por lo que es necesario un diseno termico de la envolvente que contempla un uso racional de la energia. Por la importancia termica que el vidrio tiene en la envolvente de las edificaciones y la necesidad de contar con el valor de las propiedades lo mas preciso posible para su diseno, se planteo evaluar en forma experimental el comportamiento termico de algunos vidrios que tuviesen uso tanto real como potencial en las edificaciones de nuestro pais y comparar los valores obtenidos con los valores reportados por los fabricantes dentro de limites de tolerancia o confiabilidad.

  5. Reliability calculations

    International Nuclear Information System (INIS)

    Petersen, K.E.

    1986-03-01

    Risk and reliability analysis is increasingly being used in evaluations of plant safety and plant reliability. The analysis can be performed either during the design process or during the operation time, with the purpose to improve the safety or the reliability. Due to plant complexity and safety and availability requirements, sophisticated tools, which are flexible and efficient, are needed. Such tools have been developed in the last 20 years and they have to be continuously refined to meet the growing requirements. Two different areas of application were analysed. In structural reliability probabilistic approaches have been introduced in some cases for the calculation of the reliability of structures or components. A new computer program has been developed based upon numerical integration in several variables. In systems reliability Monte Carlo simulation programs are used especially in analysis of very complex systems. In order to increase the applicability of the programs variance reduction techniques can be applied to speed up the calculation process. Variance reduction techniques have been studied and procedures for implementation of importance sampling are suggested. (author)

  6. Happiness and life satisfaction prospectively predict self-rated health, physical health, and the presence of limiting, long-term health conditions.

    Science.gov (United States)

    Siahpush, Mohammad; Spittal, Matt; Singh, Gopal K

    2008-01-01

    To examine the effect of happiness and life satisfaction on health. Longitudinal data from waves 1 and 3, conducted in 2001 and 2004, respectively, of the Household Income and Labour Dynamics in Australia survey. Australia. A total of 9981 respondents aged 18 years and older. Outcomes were self-reported health; the absence of long-term, limiting health conditions; and physical health. Happiness was assessed with the following question: "During the past 4 weeks, have you been a happy person"? Life satisfaction was determined with the following question: "All things considered, how satisfied are you with your life"? We used multiple regression analysis to estimate odds ratios (ORs), beta coefficients (beta), and 95% confidence intervals (CIs) for the associations between baseline happiness or life satisfaction and health at wave 3. Baseline happiness and life satisfaction both were positively associated at wave 3 with excellent, very good, or good health (OR = 1.50, CI = 1.33-1.70, p < .0001; and OR = 1.62, CI = 1.27-2.08, p < .0001, respectively); with the absence of long-term, limiting health conditions (OR = 1.53, CI = 1.35-1.75, p < .0001; and OR = 1.51, CI = 1.25-1.82, p < .0001, respectively); and with higher physical health levels (beta = .99, CI = .60-1.39, p < .0001; and beta = .99, CI = .20-1.78, p < .0145, respectively). This study showed that happier people and those who were more satisfied with their lives at baseline reported better health (self-rated health; absence of limiting, long-term conditions; and physical health) at the 2-year follow-up when adjusted for baseline health and other relevant covariates.

  7. Prolonging life and delaying death: The role of physicians in the context of limited intensive care resources

    Directory of Open Access Journals (Sweden)

    Bagshaw Sean M

    2009-02-01

    Full Text Available Abstract Critical care is in an emerging crisis of conflict between what individuals expect and the economic burden society and government are prepared to provide. The goal of critical care support is to prevent suffering and premature death by intensive therapy of reversible illnesses within a reasonable timeframe. Recently, it has become apparent that early support in an intensive care environment can improve patient outcomes. However, life support technology has advanced, allowing physicians to prolong life (and postpone death in circumstances that were not possible in the recent past. This has been recognized by not only the medical community, but also by society at large. One corollary may be that expectations for recovery from critical illness have also become extremely high. In addition, greater numbers of patients are dying in intensive care units after having receiving prolonged durations of life-sustaining therapy. Herein lies the emerging crisis – critical care therapy must be available in a timely fashion for those who require it urgently, yet its provision is largely dependent on a finite availability of both capital and human resources. Physicians are often placed in a troubling conflict of interest by pressures to use health resources prudently while also promoting the equitable and timely access to critical care therapy. In this commentary, these issues are broadly discussed from the perspective of the individual clinician as well as that of society as a whole. The intent is to generate dialogue on the dynamic between individual clinicians navigating the complexities of how and when to use critical care support in the context of end-of-life issues, the increasing demands placed on finite critical care capacity, and the reasonable expectations of society.

  8. Systems reliability/structural reliability

    International Nuclear Information System (INIS)

    Green, A.E.

    1980-01-01

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

  9. Reliability and Validity of the World Health Organization Quality of Life: Brief Version (WHOQOL-BREF) in a Homeless Substance Dependent Veteran Population

    Science.gov (United States)

    Garcia-Rea, Elizabeth A.; LePage, James P.

    2010-01-01

    With the high number of homeless, there is a critical need for rapid and accurate assessment of quality of life to assess program outcomes. The World Health Organization's WHOQOL-100 has demonstrated promise in accurately assessing quality-of-life in this population. However, its length may make large scale use impractical for working with a…

  10. Cross-cultural adaptation, reliability, and validity of the Turkish version of PedsQL 3.0 Arthritis Module: a quality-of-life measure for patients with juvenile idiopathic arthritis in Turkey.

    Science.gov (United States)

    Tarakci, E; Baydogan, S N; Kasapcopur, O; Dirican, A

    2013-04-01

    The aim of this study was to describe the cultural adaptation, validity, and reliability of a Turkish version of the pediatric quality-of-life inventory (PedsQL) 3.0 Arthritis Module in a population with juvenile idiopathic arthritis (JIA). A total of 169 patients with JIA and their parents were enrolled in the study. The Turkish version of the childhood health assessment questionnaire (CHAQ) was used to evaluate the validity of related domains in the PedsQL 3.0 Arthritis Module. Both the PedsQL 3.0 Arthritis Module and CHAQ were filled out by children over 8 years of age and by the parents of children 2-7 years of age. Internal reliability was poor to excellent (Cronbach's alpha coefficients 0.56-0.84 for self-reporting and 0.63-0.82 for parent reporting), and interobserver reliability varied from good to excellent (intraclass correlation coefficient (ICC) 0.79-0.91 for self-reporting and 0.80-0.88 for parent reporting) for the total scores of the PedsQL 3.0 Arthritis Module. Parent-child concordance for all scores was moderate to excellent (ICC 0.42-0.92). The PedsQL 3.0 Arthritis Module and CHAQ were highly positively correlated, with coefficients from 0.21 to 0.76, indicating concurrent validity. We demonstrated the reliability and validity of quality-of-life measurement using the Turkish version of the PedsQL 3.0 Arthritis Module in our sociocultural context. The PedsQL 3.0 Arthritis Module can be utilized as a tool for the evaluation of quality of life in patients with JIA aged 2-18 years.

  11. Bull trout life history, genetics, habitat needs, and limiting factors in Central and Northeast Oregon. Annual report 1996

    International Nuclear Information System (INIS)

    Bellerud, B.L.; Gunkel, S.; Hemmingsen, A.R.; Buchanan, D.V.; Howell, P.J.

    1997-10-01

    This study is part of a multi-year research project studying aspects of bull trout life history, ecology and genetics. This report covers the activities of the project in 1996. Results and analysis are presented in the following five areas: (1) analysis of the genetic structure of Oregon bull trout populations; (2) distribution and habitat use of bull trout and brook trout in streams containing both species; (3) bull trout spawning surveys; (4) summary and analysis of historical juvenile bull trout downstream migrant trap catches in the Grande Ronde basin; and (5) food habits and feeding behavior of bull trout alone and in sympatry with brook trout

  12. Bull Trout Life History, Genetics, Habitat Needs, and Limiting Factors in Central and Northeast Oregon. Annual Report 1996.

    Energy Technology Data Exchange (ETDEWEB)

    Bellerud, Blane L.; Gunckel, Stephanie; Hemmingsen, Alan R.; Buchanan, David V.; Howell, Philip J.

    1997-10-01

    This study is part of a multi-year research project studying aspects of bull trout life history, ecology and genetics. This report covers the activities of the project in 1996. Results and analysis are presented in the following five areas: (1) analysis of the genetic structure of Oregon bull trout populations; (2) distribution and habitat use of bull trout and brook trout in streams containing both species; (3) bull trout spawning surveys; (4) summary and analysis of historical juvenile bull trout downstream migrant trap catches in the Grande Ronde basin; and (5) food habits and feeding behavior of bull trout alone and in sympatry with brook trout.

  13. The Licancabur Project: Exploring the Limits of Life in the Highest Lake on Earth as an Analog to Martian Paleolakes

    Science.gov (United States)

    Cabrol, N. A.; Grin, E. A.; McKay, C. P.; Friedmann, I.; Diaz, G. Chong; Demergasso, C.; Kisse, K.; Grigorszky, I.; Friedmann, R. Ocampo; Hock, A.

    2003-01-01

    The Licancabur volcano (6017 m) hosts the highest and one of the least explored lakes in the world in its summit crater. It is located 22 deg.50 min. South / 67 deg.53 min. West at the boundary of Chile and Bolivia in the High-Andes. In a freezing environment, the lake located in volcano-tectonic environment combines low-oxygen, low atmospheric pressure due to altitude, and high-UV radiation (see table). However, its bottom water temperature remains above 0 C year-round. These conditions make Licancabur a unique analog to Martian paleolakes considered high-priority sites for the search for life on Mars.

  14. Educational differences in disability-free life expectancy: a comparative study of long-standing activity limitation in eight European countries.

    Science.gov (United States)

    Mäki, Netta; Martikainen, Pekka; Eikemo, Terje; Menvielle, Gwenn; Lundberg, Olle; Ostergren, Olof; Jasilionis, Domantas; Mackenbach, Johan P

    2013-10-01

    Healthy life expectancy is a composite measure of length and quality of life and an important indicator of health in aging populations. There are few cross-country comparisons of socioeconomic differences in healthy life expectancy. Most of the existing comparisons focus on Western Europe and the United States, often relying on older data. To address these deficiencies, we estimated educational differences in disability-free life expectancy for eight countries from all parts of Europe in the early 2000s. Long-standing severe disability was measured as a Global Activity Limitation Indicator (GALI) derived from the European Union Statistics on Income and Living Conditions (EU-SILC) survey. Census-linked mortality data were collected by a recent project comparing health inequalities between European countries (the EURO-GBD-SE project). We calculated sex-specific educational differences in disability-free life expectancy between the ages of 30 and 79 years using the Sullivan method. The lowest disability-free life expectancy was found among Lithuanian men and women (33.1 and 39.1 years, respectively) and the highest among Italian men and women (42.8 and 44.4 years, respectively). Life expectancy and disability-free life expectancy were directly related to the level of education, but the educational differences were much greater in the latter in all countries. The difference in the disability-free life expectancy between those with a primary or lower secondary education and those with a tertiary education was over 10 years for males in Lithuania and approximately 7 years for males in Austria, Finland and France, as well as for females in Lithuania. The difference was smallest in Italy (4 and 2 years among men and women, respectively). Highly educated Europeans can expect to live longer and spend more years in better health than those with lower education. The size of the educational difference in disability-free life expectancy varies significantly between countries

  15. Human reliability

    International Nuclear Information System (INIS)

    Bubb, H.

    1992-01-01

    This book resulted from the activity of Task Force 4.2 - 'Human Reliability'. This group was established on February 27th, 1986, at the plenary meeting of the Technical Reliability Committee of VDI, within the framework of the joint committee of VDI on industrial systems technology - GIS. It is composed of representatives of industry, representatives of research institutes, of technical control boards and universities, whose job it is to study how man fits into the technical side of the world of work and to optimize this interaction. In a total of 17 sessions, information from the part of ergonomy dealing with human reliability in using technical systems at work was exchanged, and different methods for its evaluation were examined and analyzed. The outcome of this work was systematized and compiled in this book. (orig.) [de

  16. Microelectronics Reliability

    Science.gov (United States)

    2017-01-17

    inverters  connected in a chain. ................................................. 5  Figure 3  Typical graph showing frequency versus square root of...developing an experimental  reliability estimating methodology that could both illuminate the  lifetime  reliability of advanced devices,  circuits and...or  FIT of the device. In other words an accurate estimate of the device  lifetime  was found and thus the  reliability  that  can  be  conveniently

  17. The Short Health Scale: a valid and reliable measure of health related quality of life in English speaking inflammatory bowel disease patients.

    LENUS (Irish Health Repository)

    McDermott, Edel

    2013-09-01

    Health related quality of life in inflammatory bowel disease is influenced both by disease activity as well as by the psychosocial characteristics of the individual patient. The Short Health Scale (SHS) is a four-part visual analogue scale questionnaire using open-ended questions that are designed to assess the impact of inflammatory bowel disease on a health related quality of life. The four dimensions include bowel symptoms, activities of daily life, worry and general wellbeing. It has previously been validated in Swedish and Norwegian speaking patients.

  18. Examining Microbial Survival During Infall onto Europa: An Important Limit on the Origin of Potential European Life

    Science.gov (United States)

    Fries, M.; Conrad, P.; Matney, M.; Steele, A.

    2015-01-01

    Previous work shows that transfer of material from Earth to Europa is statistically possible, opening the question of whether terrestrial biota may have transferred to Europa to populate that world. Transfer of viable organisms is a function of parameters such as ejection shock, radiation exposure, and others, applied across four phases in the transfer process: ejection from the parent body, transport through interplanetary space, infall onto the target world, and biological adaptation. If terrestrial biota could survive transport to Europa, then biology on Europa may be either the product of a separate and unrelated origin or they are the descendants of transferred terrestrial organisms. If, however, transfer of viable organisms is impossible, then any biota present on Europa must be the product of a biological origin independent from terrestrial life. We will investigate the survival likelihood of material falling onto Europa.

  19. Electrophoretic characterization of protein interactions suggesting limited feasibility of accelerated shelf-life testing of ultra-high temperature milk.

    Science.gov (United States)

    Grewal, Manpreet Kaur; Chandrapala, Jayani; Donkor, Osaana; Apostolopoulos, Vasso; Vasiljevic, Todor

    2017-01-01

    Accelerated shelf-life testing is applied to a variety of products to estimate keeping quality over a short period of time. The industry has not been successful in applying this approach to ultra-high temperature (UHT) milk because of chemical and physical changes in the milk proteins that take place during processing and storage. We investigated these protein changes, applying accelerated shelf-life principles to UHT milk samples with different fat levels and using native- and sodium dodecyl sulfate-PAGE. Samples of UHT skim and whole milk were stored at 20, 30, 40, and 50°C for 28d. Irrespective of fat content, UHT treatment had a similar effect on the electrophoretic patterns of milk proteins. At the start of testing, proteins were bonded mainly through disulfide and noncovalent interactions. However, storage at and above 30°C enhanced protein aggregation via covalent interactions. The extent of aggregation appeared to be influenced by fat content; whole milk contained more fat than skim milk, implying aggregation via melted or oxidized fat, or both. Based on reduction in loss in absolute quantity of individual proteins, covalent crosslinking in whole milk was facilitated mainly by products of lipid oxidation and increased access to caseins for crosslinking reactions. Maillard and dehydroalanine products were the main contributors involved in protein changes in skim milk. Protein crosslinking appeared to follow a different pathway at higher temperatures (≥40°C) than at lower temperatures, making it very difficult to extrapolate these changes to protein interactions at lower temperatures. Copyright © 2017 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

  20. A social capital framework for palliative care: supporting health and well-being for people with life-limiting illness and their carers through social relations and networks.

    Science.gov (United States)

    Lewis, Joanne M; DiGiacomo, Michelle; Luckett, Tim; Davidson, Patricia M; Currow, David C

    2013-01-01

    Social relations and networks are vital for sustaining and enhancing end-of-life care. The social capital concept supports a framework to understand the association between social relations and well-being; yet, to date, there has been very limited investigation of social capital in the palliative care literature. A framework for understanding social contexts in end-of-life care is necessary. To summarize the literature on social capital, well-being, and quality of life for key outcomes to inform a model of social capital in palliative care. The electronic databases MEDLINE (1997 to March 2011), Embase (1997 to March 2011), CINAHL (1997 to March 2011), and PsycINFO (1997 to March 2011) were searched using key/MeSH search terms of "social capital," "palliative care," and "well-being" and/or "quality of life." The literature was reviewed to identify key concepts to develop and inform a palliative care social capital framework. A total of 93 articles were included in the literature review, with only two articles identifying discourse on social capital and palliative care. Four key areas integrating the social capital outcomes informed a framework for palliative care. The social capital concept provides a structure for understanding how the organization and meaning of social contexts can potentially enhance or hinder end-of-life care. Research that identifies specificity in application of social capital concepts is fundamental to issues of access to services, sustaining levels of care, quality of life, and well-being. The importance of "bridged" social capital relations and networks for improved resource acquisition and information flow was identified in the literature and outlined within the palliative care social capital framework. Differential access to social capital by disadvantaged groups provides further impetus to engage a model of social capital for palliative care. Copyright © 2013 U.S. Cancer Pain Relief Committee. Published by Elsevier Inc. All rights

  1. PHENOTYPIC DIFFERENTIATION AT SOUTHERN LIMIT BORDERS: THE CASE STUDY OF TWO FUCOID MACROALGAL SPECIES WITH DIFFERENT LIFE-HISTORY TRAITS1.

    Science.gov (United States)

    Araújo, Rita; Serrão, Ester A; Sousa-Pinto, Isabel; Åberg, Per

    2011-06-01

    Marginal populations are often geographically isolated, smaller, and more fragmented than central populations and may frequently have to face suboptimal local environmental conditions. Persistence of these populations frequently involves the development of adaptive traits at phenotypic and genetic levels. We compared population structure and demographic variables in two fucoid macroalgal species contrasting in patterns of genetic diversity and phenotypic plasticity at their southern distribution limit with a more central location. Models were Ascophyllum nodosum (L.) Le Jol. (whose extreme longevity and generation overlap may buffer genetic loss by drift) and Fucus serratus L. (with low genetic diversity at southern margins). At edge locations, both species exhibited trends in life-history traits compatible with population persistence but by using different mechanisms. Marginal populations of A. nodosum had higher reproductive output in spite of similar mortality rates at all life stages, making edge populations denser and with smaller individuals. In F. serratus, rather than demographic changes, marginal populations differed in habitat, occurring restricted to a narrower vertical habitat range. We conclude that persistence of both A. nodosum and F. serratus at the southern-edge locations depends on different strategies. Marginal population persistence in A. nodosum relies on a differentiation in life-history traits, whereas F. serratus, putatively poorer in evolvability potential, is restricted to a narrower vertical range at border locations. These results contribute to the general understanding of mechanisms that lead to population persistence at distributional limits and to predict population resilience under a scenario of environmental change. © 2011 Phycological Society of America.

  2. Life, limb or off-label recombinant VIIa use in the setting of limited blood assets: a case study.

    Science.gov (United States)

    Carr, Marcus E; Vickaryous, Brian

    2013-06-01

    Due to the lack of adequate controlled trials, the off-label use of recombinant factor VIIa (rFVIIa) to control hemorrhage in trauma patients remains controversial. The decision regarding when to initiate rFVIIa therapy is particularly problematic. Whereas most reports and trials have delayed use until significant bleeding has occurred, there is some evidence that coagulopathy develops early in some trauma patients, raising the possibility that early rFVIIa use may be more clinically efficacious. Herein, we report the case of a hemodynamically unstable patient with massive blood loss from multiple gunshot wounds and who had a potentially salvageable upper extremity. Rapid hemorrhage despite efforts to surgically control the bleeding resulted in virtual exhaustion of the facilities' limited blood component supply. Hemorrhage was controlled when rFVIIa was added to hypotensive resuscitation allowing salvage of the arm and significant conservation of blood products. This case raises the question as to whether earlier off-label use of this agent should be considered when amputation for hemorrhage control is being considered and/or conservation of limited blood assets is needed.

  3. Health-related quality of life: validity, reliability, and responsiveness of SF-36, 15D, EQ-5D [corrected] RAQoL, and HAQ in patients with rheumatoid arthritis

    DEFF Research Database (Denmark)

    Linde, Louise; Sørensen, Jan; Ostergaard, Mikkel

    2008-01-01

    .21-6.47). The longitudinal sample included 80% women, median age 60 years (22-82). Validity: all instruments discriminated between low, moderate, and high DAS28. Reliability: RAQoL and HAQ displayed good repeatability (ICC > 0.95) and internal consistency (Cronbach's alpha > 0.90). Responsiveness: SF-36 bodily pain scale......, 15D, Rheumatoid Arthritis Quality of Life Scale (RAQoL), Health Assessment Questionnaire (HAQ), and visual analog scales (VAS) for pain, fatigue, and global RA. Validity (convergent, discriminant, and known-groups) was evaluated in a cross-section of 200 patients. Reliability was evaluated...... questionnaires (at 2 weeks and 6 months) included questions about changes in health status since baseline. RESULTS: The cross-sectional sample included 77% women, median age 57 years (range 19-87), disease duration 6 years (0-58), with Disease Activity Score 28-joint count (DAS28) of 3.10 (1...

  4. Comparison of Psychological, Quality of Life, Work-Limitation, and Socioeconomic Status Between Patients With Occupational Asthma and Work-Exacerbated Asthma.

    Science.gov (United States)

    Lipszyc, Joshua C; Silverman, Frances; Holness, Dorothy Linn; Liss, Gary M; Lavoie, Kim L; Tarlo, Susan M

    2017-07-01

    The aim of this study was to compare psychological status, quality of life (QoL), work limitation, and socioeconomic status between patients with occupational asthma (OA) and work-exacerbated asthma (WEA). The following questionnaires were administered to participants: Beck anxiety and depression (II) inventories, Marks' Asthma Quality of Life Questionnaire, and Work Limitations Questionnaire. Cross-sectional analyses between OA and WEA subgroups were completed. There were 77 participants. WEA subjects had a trend to higher anxiety scores (OA = 9.2 ± 8.0, WEA = 12.8 ± 8.3, P = 0.07, Cohen d = 0.4). Depression scores trended higher for those with WEA (OA = 9.6 ± 10.3, WEA = 13.4 ± 13.5, P = 0.2, Cohen d = 0.3). QoL was comparable between groups. WEA subjects had fewer work limitations (N = 50, OA = 25.1 ± 27.3, WEA = 20.6 ± 24.4, P = 0.56, Cohen d = 0.3) and OA subjects were more likely to have reduced income. In a tertiary clinic, there were some modest differences for specific variables between OA and WEA subjects that may help inform management.

  5. Edible moisture barriers: how to assess of their potential and limits in food products shelf-life extension?

    Science.gov (United States)

    Bourlieu, C; Guillard, V; Vallès-Pamiès, B; Guilbert, S; Gontard, N

    2009-05-01

    Control of moisture transfer inside composite food products or between food and its environment remains today a major challenge in food preservation. A wide rage of film-forming compounds is now available and facilitates tailoring moisture barriers with optimized functional properties. Despite these huge potentials, a realistic assessment of the film or coating efficacy is still critical. Due to nonlinear water sorption isotherms, water-dependent diffusivities, and variations of physical state, modelling transport phenomena through edible barriers is complex. Water vapor permeability can hardly be considered as an inherent property of films and only gives a relative indication of the barrier efficacy. The formal or mechanistic models reported in literature that describe the influence of testing conditions on the barrier properties of edible films are reviewed and discussed. Most of these models have been validated on a narrow range of conditions. Conversely, few original predictive models based on Fick's Second Law have been developed to assess shelf-life extension of food products including barriers. These models, assuming complex and realistic hypothesis, have been validated in various model foods. The development of nondestructive methods of moisture content measurement should speed up model validation and allow a better comprehension of moisture transfer through edible films.

  6. Bull Trout Life History, Genetics, Habitat Needs, and Limiting Fact in Central and Northeast Oregon. Annual Report 1999.

    Energy Technology Data Exchange (ETDEWEB)

    Hemmingsen, Alan R.; Gunckel, Stephanie L.; Howell, Philip J.

    2001-08-01

    This section describes work accomplished in 1999 that continued to address two objectives of this project. These objectives are (1) determine the distribution of juvenile and adult bull trout Salvelinus confluentus and habitats associated with that distribution, and (2) determine fluvial and resident bull trout life history patterns. Completion of these objectives is intended through studies of bull trout in the Grande Ronde, Walla Walla, and John Day basins. These basins were selected because they provide a variety of habitats, from relatively degraded to pristine, and bull trout populations were thought to vary from relatively depressed to robust. In all three basins we used radio telemetry to determine the seasonal movements of bull trout. In the John Day and Walla Walla basins we also used traps to capture migrant bull trout. With these traps, we intended to determine the timing of bull trout movements both upstream and downstream, determine the relative abundance, size and age of migrant fish, and capture bull trout to be implanted with radio transmitters. In the John Day basin, we captured adult and juvenile bull trout from the upper John Day River and its tributaries, Call Creek, Reynolds Creek, and Roberts Creek. In the Walla Walla basin, we captured adult and juvenile bull trout from Mill Creek.

  7. Bull trout life history, genetics, habitat needs, and limiting fact in central and northeast Oregon/1999; ANNUAL

    International Nuclear Information System (INIS)

    Hemmingsen, A.R.; Gunckel, S.L.; Howell, P.J.

    2001-01-01

    This section describes work accomplished in 1999 that continued to address two objectives of this project. These objectives are (1) determine the distribution of juvenile and adult bull trout Salvelinus confluentus and habitats associated with that distribution, and (2) determine fluvial and resident bull trout life history patterns. Completion of these objectives is intended through studies of bull trout in the Grande Ronde, Walla Walla, and John Day basins. These basins were selected because they provide a variety of habitats, from relatively degraded to pristine, and bull trout populations were thought to vary from relatively depressed to robust. In all three basins we used radio telemetry to determine the seasonal movements of bull trout. In the John Day and Walla Walla basins we also used traps to capture migrant bull trout. With these traps, we intended to determine the timing of bull trout movements both upstream and downstream, determine the relative abundance, size and age of migrant fish, and capture bull trout to be implanted with radio transmitters. In the John Day basin, we captured adult and juvenile bull trout from the upper John Day River and its tributaries, Call Creek, Reynolds Creek, and Roberts Creek. In the Walla Walla basin, we captured adult and juvenile bull trout from Mill Creek

  8. Communication and support from health-care professionals to families, with dependent children, following the diagnosis of parental life-limiting illness: A systematic review.

    Science.gov (United States)

    Fearnley, Rachel; Boland, Jason W

    2017-03-01

    Communication between parents and their children about parental life-limiting illness is stressful. Parents want support from health-care professionals; however, the extent of this support is not known. Awareness of family's needs would help ensure appropriate support. To find the current literature exploring (1) how parents with a life-limiting illness, who have dependent children, perceive health-care professionals' communication with them about the illness, diagnosis and treatments, including how social, practical and emotional support is offered to them and (2) how this contributes to the parents' feelings of supporting their children. A systematic literature review and narrative synthesis. Embase, MEDLINE, PsycINFO, CINAHL and ASSIA ProQuest were searched in November 2015 for studies assessing communication between health-care professionals and parents about how to talk with their children about the parent's illness. There were 1342 records identified, five qualitative studies met the inclusion criteria (55 ill parents, 11 spouses/carers, 26 children and 16 health-care professionals). Parents wanted information from health-care professionals about how to talk to their children about the illness; this was not routinely offered. Children also want to talk with a health-care professional about their parents' illness. Health-care professionals are concerned that conversations with parents and their children will be too difficult and time-consuming. Parents with a life-limiting illness want support from their health-care professionals about how to communicate with their children about the illness. Their children look to health-care professionals for information about their parent's illness. Health-care professionals, have an important role but appear reluctant to address these concerns because of fears of insufficient time and expertise.

  9. Redefining reliability

    International Nuclear Information System (INIS)

    Paulson, S.L.

    1995-01-01

    Want to buy some reliability? The question would have been unthinkable in some markets served by the natural gas business even a few years ago, but in the new gas marketplace, industrial, commercial and even some residential customers have the opportunity to choose from among an array of options about the kind of natural gas service they need--and are willing to pay for. The complexities of this brave new world of restructuring and competition have sent the industry scrambling to find ways to educate and inform its customers about the increased responsibility they will have in determining the level of gas reliability they choose. This article discusses the new options and the new responsibilities of customers, the needed for continuous education, and MidAmerican Energy Company's experiment in direct marketing of natural gas

  10. Bull Trout Life History, Genetics, Habitat Needs, and Limiting Factors in Central and Northeast Oregon, Annual Report 2000.

    Energy Technology Data Exchange (ETDEWEB)

    Hemmingsen, Alan R.; Gunckel, Stephanie L.; Sankovich, Paul M.; Howell, Philip J.

    2001-11-01

    This section describes work accomplished in 2000 that continued to address two objectives of this project. These objectives are (1) determine the distribution of juvenile and adult bull trout Salvelinus confluentus and habitats associated with that distribution, and (2) determine fluvial and resident bull trout life history patterns. Completion of these objectives is intended through studies of bull trout in the Grande Ronde, Walla Walla, and John Day basins. These basins were selected because they provide a variety of habitats, from relatively degraded to pristine, and bull trout populations were thought to vary from relatively depressed to robust. In all three basins we continued to monitor the movements of bull trout with radio transmitters applied in 1998 (Hemmingsen, Bellerud, Gunckel and Howell 2001) and 1999 (Hemmingsen, Gunckel and Howell 2001). No new radio transmitters were applied to bull trout of the upper John Day River subbasin, Mill Creek (Walla Walla Basin), or the Grande Ronde Basin in 2000. We did implant radio transmitters in two bull trout incidentally captured in the John Day River near the confluence of the North Fork John Day River. In Mill Creek, we used traps to capture migrant bull trout to obtain data for the third successive year in this stream. With these traps, we intended to determine the timing of bull trout movements both upstream and downstream, and to determine the relative abundance, size and age of migrant fish. Because we captured migrant bull trout with traps for three years in the upper John Day River and its tributaries (Hemmingsen, Bellerud, Buchanan, Gunckel, Shappart and Howell 2001; Hemmingsen, Bellerud, Gunckel and Howell 2001; Hemmingsen, Gunckel and Howell 2001) and traps were no longer needed to capture bull trout for radio-tagging, no traps were operated in the John Day Basin in 2000.

  11. Bull trout life history, genetics, habitat needs, and limiting fact in central and northeast Oregon, annual report 2000.; ANNUAL

    International Nuclear Information System (INIS)

    Hemmingsen, Alan R.

    2001-01-01

    This section describes work accomplished in 2000 that continued to address two objectives of this project. These objectives are (1) determine the distribution of juvenile and adult bull trout Salvelinus confluentus and habitats associated with that distribution, and (2) determine fluvial and resident bull trout life history patterns. Completion of these objectives is intended through studies of bull trout in the Grande Ronde, Walla Walla, and John Day basins. These basins were selected because they provide a variety of habitats, from relatively degraded to pristine, and bull trout populations were thought to vary from relatively depressed to robust. In all three basins we continued to monitor the movements of bull trout with radio transmitters applied in 1998 (Hemmingsen, Bellerud, Gunckel and Howell 2001) and 1999 (Hemmingsen, Gunckel and Howell 2001). No new radio transmitters were applied to bull trout of the upper John Day River subbasin, Mill Creek (Walla Walla Basin), or the Grande Ronde Basin in 2000. We did implant radio transmitters in two bull trout incidentally captured in the John Day River near the confluence of the North Fork John Day River. In Mill Creek, we used traps to capture migrant bull trout to obtain data for the third successive year in this stream. With these traps, we intended to determine the timing of bull trout movements both upstream and downstream, and to determine the relative abundance, size and age of migrant fish. Because we captured migrant bull trout with traps for three years in the upper John Day River and its tributaries (Hemmingsen, Bellerud, Buchanan, Gunckel, Shappart and Howell 2001; Hemmingsen, Bellerud, Gunckel and Howell 2001; Hemmingsen, Gunckel and Howell 2001) and traps were no longer needed to capture bull trout for radio-tagging, no traps were operated in the John Day Basin in 2000

  12. Initial Reliability and Validity of the Life Satisfaction Scale for Problem Youth in a Sample of Drug Abusing and Conduct Disordered Youth

    Science.gov (United States)

    Donohue, Brad; Teichner, Gordon; Azrin, Nathan; Weintraub, Noah; Crum, Thomas A.; Murphy, Leah; Silver, N. Clayton

    2003-01-01

    Responses to Life Satisfaction Scale for Problem Youth (LSSPY) items were examined in a sample of 193 substance abusing and conduct disordered adolescents. In responding to the LSSPY, youth endorse their percentage of happiness (0 to 100%) in twelve domains (i.e., friendships, family, school, employment/work, fun activities, appearance, sex…

  13. Reliability, construct and criterion validity of the KIDSCREEN-10 score: A short measure for children and adolescents' well-being and health-related quality of life

    NARCIS (Netherlands)

    Ravens-Sieberer, U.; Erhart, M.; Rajmil, L.; Herdman, M.; Auquier, P.; Bruil, J.; Power, M.; Duer, W.; Abel, T.; Czemy, L.; Mazur, J.; Czimbalmos, A.; Tountas, Y.; Hagquist, C.; Kilroe, J.

    2010-01-01

    Background: To assess the criterion and construct validity of the KIDSCREEN-10 well-being and health-related quality of life (HRQoL) score, a short version of the KIDSCREEN-52 and KIDSCREEN-27 instruments. Methods: The child self-report and parent report versions of the KIDSCREEN-10 were tested in a

  14. A comparison between patients with epiphora and cataract of the activity limitations they experience in daily life due to their visual disability.

    Science.gov (United States)

    Bohman, Elin; Wyon, Maria; Lundström, Mats; Dafgård Kopp, Eva

    2018-02-01

    The objective of this study was to compare patients with epiphora and cataract in terms of the activity limitations they experience in daily life due to their visual disability and to validate the use of the Catquest-9SF questionnaire for epiphora patients. Seventy-two consecutively encountered adult patients with confirmed lacrimal obstruction and listed for dacryocystorhinostomy (DCR) or lacrimal intubation at the St. Erik Eye Hospital, Stockholm, Sweden, completed the Catquest-9SF questionnaire, which measures activity limitations in daily life due to visual disability. The psychometric qualities of the Catquest-9SF results obtained from this group of patients were evaluated by Rasch analysis. Rasch analysis was further employed to convert the ordinal raw data to a Rasch score for comparison with the preoperative scores of patients registered in the Swedish National Cataract Register (NCR) during March 2013. The Catquest-9SF exhibited good psychometric qualities when investigating epiphora patients, with the exception of a misfit for Item 4, the item regarding facial recognition. On the Rasch scale (-5.43 = no activity limitations to +5.01 = severe activity limitations), the mean score for epiphora patients was -0.82 while for patients listed for 1st eye and 2nd eye cataract surgery it was -0.17 and -0.76, respectively. An equivalence test confirmed that the reported visual disability of epiphora patients was not significantly different from visual disability reported by patients waiting for 2nd eye cataract surgery. The Catquest-9SF is a valid measure of visual disability in patients with epiphora. Epiphora patients experience visual disability to the same degree as patients awaiting 2nd eye cataract surgery. © 2017 Acta Ophthalmologica Scandinavica Foundation. Published by John Wiley & Sons Ltd.

  15. Reliability of patient-reported outcome instruments in US adults with hemophilia: the Pain, Functional Impairment and Quality of life (P-FiQ study

    Directory of Open Access Journals (Sweden)

    Kempton CL

    2017-09-01

    Full Text Available Christine L Kempton,1 Michael Wang,2 Michael Recht,3 Anne Neff,4 Amy D Shapiro,5 Amit Soni,6 Roshni Kulkarni,7 Tyler W Buckner,2 Katharine Batt,8 Neeraj N Iyer,9 David L Cooper9 1Departments of Pediatrics and Hematology and Medical Oncology, Emory University School of Medicine, Atlanta, GA, USA; 2Hemophilia and Thrombosis Center, University of Colorado School of Medicine, Aurora, CO, USA; 3The Hemophilia Center, Oregon Health & Science University, Portland, OR, USA; 4Hematology and Medical Oncology, Cleveland Clinic, Cleveland, OH, USA; 5Indiana Hemophilia & Thrombosis Center, Indianapolis, IN, USA; 6Center for Inherited Blood Disorders and CHOC Children’s Hospital/UC Irvine, Orange, CA, USA; 7MSU Center for Bleeding and Clotting Disorders, Michigan State University, East Lansing, MI, USA; 8Hematology and Oncology, Wake Forest School of Medicine, Winston-Salem, NC, USA; 9Clinical, Medical and Regulatory Affairs, Novo Nordisk Inc., Plainsboro, NJ, USA Background: Hemophilia is marked by frequent joint bleeding, resulting in pain and functional impairment.Objective: This study aimed to assess the reliability of five patient-reported outcome (PRO instruments in people with hemophilia (PWH in a non-bleeding state.Methods: Adult male PWH of any severity and inhibitor status, with a history of joint pain or bleeding, completed a pain history and five PRO instruments (EQ-5D-5L, Brief Pain Inventory v2 [BPI], International Physical Activity Questionnaire [IPAQ], Short Form 36 Health Survey v2 [SF-36v2], and Hemophilia Activities List [HAL] during their routine comprehensive care visit. Patients were approached to complete the PRO instruments again at the end of their visit while in a similar non-bleeding state. Concordance of individual questionnaire items and correlation between domain scores were assessed using intra-class correlation coefficient (ICC.Results: Participants completing the retest (n=164 had a median age of 33.9 years. Median time for

  16. Qualitative study of the communication expectations of clients accessing oncology care at a tertiary referral center for dogs with life-limiting cancer.

    Science.gov (United States)

    Stoewen, Debbie L; Coe, Jason B; MacMartin, Clare; Stone, Elizabeth A; E Dewey, Catherine

    2014-10-01

    To describe the process aspects (communication) of the information expectations of clients accessing oncology care services at a tertiary referral center for dogs with life-limiting cancer. Qualitative analysis of data acquired during in-person single and dyadic interviews. 43 dog owners participating in 30 interviews. Independent in-person interviews were conducted with standardized open- and closed-ended questions from April to October 2009. Thematic analysis was performed on transcripts of the interview discussions. The participants expected information to be communicated in a forthright manner; in multiple formats; with understandable language; in an unrushed environment wherein staff took the time to listen, answer all questions, and repeat information when necessary; on a continuous basis, with 24-hour access to address questions or concerns; in a timely manner; with positivity; with compassion and empathy; with a nonjudgmental attitude; and through staff with whom they had established relationships. Results indicated that the manner in which information is communicated is vitally important to clients of dogs with life-limiting cancer in that it not only facilitates comprehension but also creates a humanistic environment from which clients derive the psychosocial support needed to successfully cope with their pet's condition.

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

    International Nuclear Information System (INIS)

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

    2013-01-01

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

  18. Disease-specific questionnaire for quality of life in patients with peripheral arterial occlusive disease in the stage of critical ischemia (FLeQKI) - methodical development of a specific measuring instrument and psychometric evaluation of its validity and reliability. Pt. 1

    International Nuclear Information System (INIS)

    Wohlgemuth, W.A.; Bohndorf, K.; Kirchhof, K.; Olbricht, W.; Klarmann, S.; Engelhardt, M.; Freitag, M.H.; Woelfle, K.

    2007-01-01

    Purpose: To develop a disease-specific measuring instrument for quality of life in German-speaking patients with peripheral arterial occlusive disease in the stage of critical ischemia and to test it in a prospective study for validity and reliability. Materials and methods: We developed a questionnaire compiling items representing subjective disease relevant health states. With 35 of these items, we designed the scales comorbidity (KO), physical pain (SZ), physical functioning (KF), physical state (KS), social functioning (SB), mental health (PB), and therapy-induced limitations (TE). Each item was to be valued as never, seldom, often or always. The scales were standardized with a control group of 40 individuals without peripheral arterial occlusive disease who were interviewed twice in an interval of 6 months using both the FLeQKI and the Medical Outcomes Study Group Short Form 36 (SF-36). Convergent and discriminative validity was determined in 65 consecutive in-patients with peripheral occlusive arterial disease in the stage of critical ischemia who were interviewed with FLeQKI and SF-36 prior to percutaneous transluminal angioplasty (PTA) or bypass operation and 1 month and 6 months after. The internal consistency and test-retest reliability of the FLeQKI were determined in the control group. For statistical analysis, Cronbach's α Test and Pearsons Product Moment Correlation were used. Results: The control group consisted of 21 men and 19 women with an age of 73.4 ± 7.8, and the treatment group was comprised of 35 men and 30 women with an age of 75.1 ± 7.0. In the treatment group, convergent validity reached high values in the scales SB, KF, PB, and SZ (r = 0.41 - 0.70). With their discriminative validity (r = -0.04 - 0.30), TE and KS were independent, specific dimensions of life quality. The control group showed good values for internal consistency (Cronbach's α = 0.54 - 0.93) and for test-retest reliability (r = 0.44 - 0.96). Conclusion: The FLeQKI is

  19. Designing reliability into high-effectiveness industrial gas turbine regenerators

    International Nuclear Information System (INIS)

    Valentino, S.J.

    1979-01-01

    The paper addresses the measures necessary to achieve a reliable regenerator design that can withstand higher temperatures (1000-1200 F) and many start and stop cycles - conditions encountered in high-efficiency operation in pipeline applications. The discussion is limited to three major areas: (1) structural analysis of the heat exchanger core - the part of the regenerator that must withstand the higher temperatures and cyclic duty (2) materials data and material selection and (3) a comprehensive test program to demonstrate the reliability of the regenerator. This program includes life-cycle tests, pressure containment in fin panels, core-to-core joint structural test, bellows pressure containment test, sliding pad test, core gas-side passage flow distribution test, and production test. Today's regenerators must have high cyclic life capability, stainless steel construction, and long fault-free service life of 120,000 hr

  20. INSPIRE (INvestigating Social and PractIcal suppoRts at the End of life): Pilot randomised trial of a community social and practical support intervention for adults with life-limiting illness.

    LENUS (Irish Health Repository)

    McLoughlin, Kathleen

    2015-11-24

    For most people, home is the preferred place of care and death. Despite the development of specialist palliative care and primary care models of community based service delivery, people who are dying, and their families\\/carers, can experience isolation, feel excluded from social circles and distanced from their communities. Loneliness and social isolation can have a detrimental impact on both health and quality of life. Internationally, models of social and practical support at the end of life are gaining momentum as a result of the Compassionate Communities movement. These models have not yet been subjected to rigorous evaluation. The aims of the study described in this protocol are: (1) to evaluate the feasibility, acceptability and potential effectiveness of The Good Neighbour Partnership (GNP), a new volunteer-led model of social and practical care\\/support for community dwelling adults in Ireland who are living with advanced life-limiting illness; and (2) to pilot the method for a Phase III Randomised Controlled Trial (RCT).

  1. Analysis of fatigue reliability for high temperature and high pressure multi-stage decompression control valve

    Science.gov (United States)

    Yu, Long; Xu, Juanjuan; Zhang, Lifang; Xu, Xiaogang

    2018-03-01

    Based on stress-strength interference theory to establish the reliability mathematical model for high temperature and high pressure multi-stage decompression control valve (HMDCV), and introduced to the temperature correction coefficient for revising material fatigue limit at high temperature. Reliability of key dangerous components and fatigue sensitivity curve of each component are calculated and analyzed by the means, which are analyzed the fatigue life of control valve and combined with reliability theory of control valve model. The impact proportion of each component on the control valve system fatigue failure was obtained. The results is shown that temperature correction factor makes the theoretical calculations of reliability more accurate, prediction life expectancy of main pressure parts accords with the technical requirements, and valve body and the sleeve have obvious influence on control system reliability, the stress concentration in key part of control valve can be reduced in the design process by improving structure.

  2. Evaluation of aileron actuator reliability with censored data

    Directory of Open Access Journals (Sweden)

    Li Huaiyuan

    2015-08-01

    Full Text Available For the purpose of enhancing reliability of aileron of Airbus new-generation A350XWB, an evaluation of aileron reliability on the basis of maintenance data is presented in this paper. Practical maintenance data contains large number of censoring samples, information uncertainty of which makes it hard to evaluate reliability of aileron actuator. Considering that true lifetime of censoring sample has identical distribution with complete sample, if censoring sample is transformed into complete sample, conversion frequency of censoring sample can be estimated according to frequency of complete sample. On the one hand, standard life table estimation and product limit method are improved on the basis of such conversion frequency, enabling accurate estimation of various censoring samples. On the other hand, by taking such frequency as one of the weight factors and integrating variance of order statistics under standard distribution, weighted least square estimation is formed for accurately estimating various censoring samples. Large amounts of experiments and simulations show that reliabilities of improved life table and improved product limit method are closer to the true value and more conservative; moreover, weighted least square estimate (WLSE, with conversion frequency of censoring sample and variances of order statistics as the weights, can still estimate accurately with high proportion of censored data in samples. Algorithm in this paper has good effect and can accurately estimate the reliability of aileron actuator even with small sample and high censoring rate. This research has certain significance in theory and engineering practice.

  3. INSPIRE (INvestigating Social and PractIcal suppoRts at the End of life): Pilot randomised trial of a community social and practical support intervention for adults with life-limiting illness.

    Science.gov (United States)

    McLoughlin, Kathleen; Rhatigan, Jim; McGilloway, Sinead; Kellehear, Allan; Lucey, Michael; Twomey, Feargal; Conroy, Marian; Herrera-Molina, Emillio; Kumar, Suresh; Furlong, Mairead; Callinan, Joanne; Watson, Max; Currow, David; Bailey, Christopher

    2015-11-24

    For most people, home is the preferred place of care and death. Despite the development of specialist palliative care and primary care models of community based service delivery, people who are dying, and their families/carers, can experience isolation, feel excluded from social circles and distanced from their communities. Loneliness and social isolation can have a detrimental impact on both health and quality of life. Internationally, models of social and practical support at the end of life are gaining momentum as a result of the Compassionate Communities movement. These models have not yet been subjected to rigorous evaluation. The aims of the study described in this protocol are: (1) to evaluate the feasibility, acceptability and potential effectiveness of The Good Neighbour Partnership (GNP), a new volunteer-led model of social and practical care/support for community dwelling adults in Ireland who are living with advanced life-limiting illness; and (2) to pilot the method for a Phase III Randomised Controlled Trial (RCT). The INSPIRE study will be conducted within the Medical Research Council (MRC) Framework for the Evaluation of Complex Interventions (Phases 0-2) and includes an exploratory two-arm delayed intervention randomised controlled trial. Eighty patients and/or their carers will be randomly allocated to one of two groups: (I) Intervention: GNP in addition to standard care or (II) Control: Standard Care. Recipients of the GNP will be asked for their views on participating in both the study and the intervention. Quantitative and qualitative data will be gathered from both groups over eight weeks through face-to-face interviews which will be conducted before, during and after the intervention. The primary outcome is the effect of the intervention on social and practical need. Secondary outcomes are quality of life, loneliness, social support, social capital, unscheduled health service utilisation, caregiver burden, adverse impacts, and satisfaction

  4. A quantitative calculation for software reliability evaluation

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Young-Jun; Lee, Jang-Soo [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2016-10-15

    To meet these regulatory requirements, the software used in the nuclear safety field has been ensured through the development, validation, safety analysis, and quality assurance activities throughout the entire process life cycle from the planning phase to the installation phase. A variety of activities, such as the quality assurance activities are also required to improve the quality of a software. However, there are limitations to ensure that the quality is improved enough. Therefore, the effort to calculate the reliability of the software continues for a quantitative evaluation instead of a qualitative evaluation. In this paper, we propose a quantitative calculation method for the software to be used for a specific operation of the digital controller in an NPP. After injecting random faults in the internal space of a developed controller and calculating the ability to detect the injected faults using diagnostic software, we can evaluate the software reliability of a digital controller in an NPP. We tried to calculate the software reliability of the controller in an NPP using a new method that differs from a traditional method. It calculates the fault detection coverage after injecting the faults into the software memory space rather than the activity through the life cycle process. We attempt differentiation by creating a new definition of the fault, imitating the software fault using the hardware, and giving a consideration and weights for injection faults.

  5. Dependent systems reliability estimation by structural reliability approach

    DEFF Research Database (Denmark)

    Kostandyan, Erik; Sørensen, John Dalsgaard

    2014-01-01

    Estimation of system reliability by classical system reliability methods generally assumes that the components are statistically independent, thus limiting its applicability in many practical situations. A method is proposed for estimation of the system reliability with dependent components, where...... the leading failure mechanism(s) is described by physics of failure model(s). The proposed method is based on structural reliability techniques and accounts for both statistical and failure effect correlations. It is assumed that failure of any component is due to increasing damage (fatigue phenomena...... identification. Application of the proposed method can be found in many real world systems....

  6. Proposed reliability cost model

    Science.gov (United States)

    Delionback, L. M.

    1973-01-01

    The research investigations which were involved in the study include: cost analysis/allocation, reliability and product assurance, forecasting methodology, systems analysis, and model-building. This is a classic example of an interdisciplinary problem, since the model-building requirements include the need for understanding and communication between technical disciplines on one hand, and the financial/accounting skill categories on the other. The systems approach is utilized within this context to establish a clearer and more objective relationship between reliability assurance and the subcategories (or subelements) that provide, or reenforce, the reliability assurance for a system. Subcategories are further subdivided as illustrated by a tree diagram. The reliability assurance elements can be seen to be potential alternative strategies, or approaches, depending on the specific goals/objectives of the trade studies. The scope was limited to the establishment of a proposed reliability cost-model format. The model format/approach is dependent upon the use of a series of subsystem-oriented CER's and sometimes possible CTR's, in devising a suitable cost-effective policy.

  7. Measuring health-related quality of life in children with cancer living in mainland China: feasibility, reliability and validity of the Chinese mandarin version of PedsQL 4.0 Generic Core Scales and 3.0 Cancer Module

    Directory of Open Access Journals (Sweden)

    Ji Yi

    2011-11-01

    Full Text Available Abstract Background The Pediatric Quality of Life Inventory (PedsQL is widely used instrument to measure pediatric health-related quality of life (HRQOL for children aged 2 to 18 years. The purpose of the current study was to investigate the feasibility, reliability and validity of the Chinese mandarin version of the PedsQL 4.0 Generic Core Scales and 3.0 Cancer Module in a group of Chinese children with cancer. Methods The PedsQL 4.0 Genetic Core Scales and the PedsQL 3.0 Cancer Module were administered to children with cancer (aged 5-18 years and parents of such children (aged 2-18 years. For comparison, a survey on a demographically group-matched sample of the general population with children (aged 5-18 and parents of children (aged 2-18 years was conducted with the PedsQL 4.0 Genetic Core Scales. Result The minimal mean percentage of missing item responses (except the School Functioning scale supported the feasibility of the PedsQL 4.0 Generic Core Scales and 3.0 Cancer Module for Chinese children with cancer. Most of the scales showed satisfactory reliability with Cronbach's α of exceeding 0.70, and all scales demonstrated sufficient test-retest reliability. Assessing the clinical validity of the questionnaires, statistically significant difference was found between healthy children and children with cancer, and between children on-treatment versus off-treatment ≥12 months. Positive significant correlations were observed between the scores of the PedsQL 4.0 Generic Core Scale and the PedsQL 3.0 Cancer Module. Exploratory factor analysis demonstrated sufficient factorial validity. Moderate to good agreement was found between child self- and parent proxy-reports. Conclusion The findings support the feasibility, reliability and validity of the Chinese Mandarin version of PedsQL 4.0 Generic Core Scales and 3.0 Cancer Module in children with cancer living in mainland China.

  8. Adolescent self-report and parent proxy-report of health-related quality of life: an analysis of validity and reliability of PedsQL 4.0 among a sample of Malaysian adolescents and their parents.

    Science.gov (United States)

    Kaartina, Sanker; Chin, Yit Siew; Fara Wahida, Rezali; Woon, Fui Chee; Hiew, Chu Chien; Zalilah, Mohd Shariff; Mohd Nasir, Mohd Taib

    2015-04-08

    The Pediatric Quality of Life Inventory Generic Core Scales (PedsQL) 4.0 is a generalized assessment of health-related quality of life (HRQoL) based on adolescent self-report and parent proxy-report. This study aims to determine the construct validity and reliability of PedsQL 4.0 among a sample of Malaysian adolescents and parents. A cross-sectional study was carried out at three selected public schools in the state of Selangor. A total of 379 Malaysian adolescents completed the PedsQL 4.0 adolescent self-report and 218 (55.9%) parents completed the PedsQL 4.0 parent proxy-report. Weight and height of adolescents were measured and BMI-for-age by sex was used to determine their body weight status. There were 50.8% male and 49.2% female adolescents who participated in this study (14.25 ± 1.23 years). The prevalence of overweight and obesity (25.8%) was four times higher than the prevalence of severe thinness and thinness (6.1%). Construct validity was analyzed using Confirmatory Factor Analysis (CFA). Based on CFA, adolescent self-report and parent proxy-report met the criteria of convergent validity (factor loading > 0.5, Average Variance Extracted (AVE) > 0.5, Construct Reliability > 0.7) and showed good fit to the data. The adolescent self-report and parent proxy-report exhibited discriminant validity as the AVE values were larger than the R(2) values. Cronbach's alpha coefficients of the adolescent self-report (α = 0.862) and parent proxy-report (α = 0.922) showed these instruments are reliable. Parents perceived the HRQoL of adolescents was poorer compared to the perception of the adolescent themselves (t = 5.92, p 0.05). Parent proxy-report was negatively associated with the adolescents' BMI-for-age (r = -0.152, p 0.05). Adolescent self-report and parent proxy-report of the PedsQL 4.0 are valid and reliable to assess HRQoL of Malaysian adolescents. Future studies are recommended to use both adolescent self-report and parent-proxy report of HRQoL as

  9. Experience based reliability centered maintenance

    International Nuclear Information System (INIS)

    Haenninen, S.; Laakso, K.

    1993-03-01

    The systematic analysis and documentation of operating experiences should be included in a living NPP life management program. Failure mode and effects and maintenance effects analyses are suitable methods for analysis of the failure and corrective maintenance experiences of equipment. Combined use of the information on occurred functional failures and the decision tree logic of the reliability centered maintenance identifies applicable and effective preventive maintenance tasks of equipment in an old plant. In this study the electrical motor drives of closing and isolation valves (MOV) of TVO and Loviisa nuclear power plants were selected to serve as pilot study objects. The study was limited to valve drives having actuators manufactured by AUMA in Germany. The fault and maintenance history of MOVs from 1981 up to and including October 1991 in different safety and process systems at TVO 1 and 2 nuclear power units was at first analyzed in a systematic way. The scope of the components studied was 81 MOVs in safety-related systems and 127 other MOVs per each TVO unit. In the case of the Loviisa plant, the observation period was limited to three years, i.e. from February 1989 up to February 1992. The scope of the Loviisa 1 and 2 components studied was 44 respectively 95 MOVs. (25 refs., 22 figs., 8 tabs.)

  10. Storytelling in the Early Bereavement Period to Reduce Emotional Distress Among Surrogates Involved in a Decision to Limit Life Support in the ICU: A Pilot Feasibility Trial.

    Science.gov (United States)

    Barnato, Amber E; Schenker, Yael; Tiver, Greer; Dew, Mary Amanda; Arnold, Robert M; Nunez, Eduardo R; Reynolds, Charles F

    2017-01-01

    Surrogate decision makers involved in decisions to limit life support for an incapacitated patient in the ICU have high rates of adverse emotional health outcomes distinct from normal processes of grief and bereavement. Narrative self-disclosure (storytelling) reduces emotional distress after other traumatic experiences. We sought to assess the feasibility, acceptability, and tolerability of storytelling among bereaved surrogates involved in a decision to limit life support in the ICU. Pilot single-blind trial. Five ICUs across three hospitals within a single health system between June 2013 and November 2014. Bereaved surrogates of ICU patients. Storytelling and control conditions involved printed bereavement materials and follow-up assessments. Storytelling involved a single 1- to 2-hour home or telephone visit by a trained interventionist who elicited the surrogate's story. The primary outcomes were feasibility (rates of enrollment, intervention receipt, 3- and 6-mo follow-up), acceptability (closed and open-ended end-of-study feedback at 6 mo), and tolerability (acute mental health services referral). Of 53 eligible surrogates, 32 (60%) consented to treatment allocation. Surrogates' mean age was 55.5 (SD, 11.8), and they were making decisions for their parent (47%), spouse (28%), sibling (13%), child (3%), or other relation (8%). We allocated 14 to control and 18 to storytelling, 17 of 18 (94%) received storytelling, 14 of 14 (100%) and 13 of 14 (94%) control subjects and 16 of 18 (89%) and 17 of 18 (94%) storytelling subjects completed their 3- and 6-month telephone assessments. At 6 months, nine of 13 control participants (69%) and 16 of 17 storytelling subjects (94%) reported feeling "better" or "much better," and none felt "much worse." One control subject (8%) and one storytelling subject (6%) said that the study was burdensome, and one control subject (8%) wished they had not participated. No subjects required acute mental health services referral. A

  11. Functional limitation and health-related quality of life, and associated factors among long term stroke survivors in a Malaysian community.

    Science.gov (United States)

    Nor Azlin, M N; Aziz, N A; Saperi, B S; Aljunid, S M

    2016-12-01

    this study aimed to evaluate function and quality of life (QoL) and associated factors among long term stroke survivors in the Malaysian community. A cross-sectional study was conducted involving stroke survivors living in the community at two or more years post-stroke. Eligible participants with the diagnosis of stroke were identified from 2005-2010 case mix database of a tertiary hospital. the patients' medical records were analysed and data on demographic and clinical profiles were collected. telephone interviews were conducted to assess existing stroke-related impairments, comorbidities, stroke recurrences, current level of function and QoL, with the usage of rivermead mobility index (rMI), barthel index (bI) and stroke specific quality of life scale (ssQOL). A total of 203 stroke survivors; mean age 64.5 (standard Deviation(sD) 12.2) years, 45.3% males, stroke duration 44.7 (sD 13.8) months completed the interviews. Mean rMI was 11.7 (sD 3.4) and bI was 89.8 (sD 19.8). Forty three percent and 99% had difficulty in ascending/descending stairs and fast walking, respectively. Up to 20% had limitations in most of the bI subsets. Mean ssQOL was 207.6 (sD 37.2), with domains mostly affected were 'energy' and 'social role'. Function and QOL were both influenced by age (p<0.01) and stroke related impairments (p<0.05), but not by co-morbidities or stroke recurrence. QoL and function (both mobility and ADL) were strongly positively correlated with each other (p<0.01). It was observed that functional limitations especially mobility, remains post-stroke major problem and were attributed mainly to stroke-related impairments.

  12. 24. MPA-seminar: safety and reliability of plant technology with special emphasis on integrity and life management. Vol. 2. Papers 28-63; 24. MPA-Seminar: Sicherheit und Verfuegbarkeit in der Anlagentechnik mit dem Schwerpunk Integritaet und Lebensdauermanagement. Bd. 2. Vortraege 28-63

    Energy Technology Data Exchange (ETDEWEB)

    1999-09-01

    The second volume is dedicated to the safety and reliability of plant technology with special emphasis on the integrity and life management. The following topics are discussed: 1. Integrity of vessels, pipes and components. 2. Fracture mechanics. 3. Measures for the extension of service life, and 4. Online Monitoring. All 30 contributions are separately analyzed for this database. (orig.)

  13. 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

  14. New limit for the half-life of double beta decay of {sup 94}Zr to the first excited state of {sup 94}Mo

    Energy Technology Data Exchange (ETDEWEB)

    Dokania, N.; Nanal, V.; Gupta, G.; Pillay, R.G.; Ghosh, C. [Tata Institute of Fundamental Research, Department of Nuclear and Atomic Physics, Mumbai (India); Pal, S. [Tata Institute of Fundamental Research, Pelletron Linac Facility, Mumbai (India); Rath, P.K. [University of Lucknow, Department of Physics, Lucknow (India); Tretyak, V.I. [Institute for Nuclear Research, Kyiv (Ukraine); Garai, A.; Krishnamoorthy, H. [Tata Institute of Fundamental Research, India-based Neutrino Observatory, Mumbai (India); Homi Bhabha National Institute, Mumbai (India); Raina, P.K. [Indian Institute of Technology, Department of Physics, Rupnagar (India); Bhushan, K.G. [Bhabha Atomic Research Centre, Technical Physics Division, Mumbai (India)

    2017-04-15

    Neutrinoless double beta decay is a phenomenon of fundamental interest in particle physics. The decay rates of double beta decay transitions to the excited states can provide input for Nuclear Transition Matrix Element calculations for the relevant two neutrino double beta decay process. It can be useful as supplementary information for the calculation of Nuclear Transition Matrix Element for the neutrinoless double beta decay process. In the present work, double beta decay of {sup 94}Zr to the 2{sup +}{sub 1} excited state of {sup 94}Mo at 871.1 keV is studied using a low background ∝ 230 cm{sup 3} HPGe detector. No evidence of this decay was found with a 232 g.y exposure of natural zirconium. The lower half-life limit obtained for the double beta decay of {sup 94}Zr to the 2{sup +}{sub 1} excited state of {sup 94}Mo is T{sub 1/2}(0ν + 2ν) > 3.4 x 10{sup 19} y at 90% C.L., an improvement by a factor of ∝ 4 over the existing experimental limit at 90% C.L. The sensitivity is estimated to be T{sub 1/2} (0ν + 2ν) > 2.0 x 10{sup 19} y at 90% C.L. using the Feldman-Cousins method. (orig.)

  15. Reliability Assessment of Concrete Bridges

    DEFF Research Database (Denmark)

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

    This paper is partly based on research performed for the Highways Agency, London, UK under the project DPU/9/44 "Revision of Bridge Assessment Rules Based on Whole Life Performance: concrete bridges". It contains the details of a methodology which can be used to generate Whole Life (WL) reliability...... profiles. These WL reliability profiles may be used to establish revised rules for concrete bridges. This paper is to some extend based on Thoft-Christensen et. al. [1996], Thoft-Christensen [1996] et. al. and Thoft-Christensen [1996]....

  16. Multi-life-stage monitoring system based on fibre bragg grating sensors for more reliable wind turbine rotor blades: Experimental and numerical analysis of deformation and failure in composite materials

    DEFF Research Database (Denmark)

    Pereira, Gilmar Ferreira

    , design and optimisation of offshore wind turbines. The MareWint main scientific objective is to optimise the design of offshore wind turbines, maximise reliability, and minimise maintenance costs. Integrated within the innovative rotor blades work-package, this PhD project is focused on damage analysis...... are used to improve the design process, and the implemented sensor are used to control the manufacturing and operation stage of a wind turbine rotor blade. The FBG sensors measurement principle is analysed from a multi-life-stage (design, material testing, manufacturing, and operation) perspective......, and supported/validated by numerical models, software tools, signal post-processing, and experimental validation. The damage in the wind turbine rotor blade is analysed from a material perspective (fibre reinforced polymers) and used as a design property, meaning that damage is accepted in an operational wind...

  17. Limitation of life-sustaining treatment in patients with prolonged admission to the ICU. Current situation in Spain as seen from the EPIPUSE Study.

    Science.gov (United States)

    Hernández-Tejedor, A; Martín Delgado, M C; Cabré Pericas, L; Algora Weber, A

    2015-10-01

    Limitation of life-sustaining treatment (LLST) is a recommended practice in certain circumstances. Limitation practices are varied, and their application differs from one center to another. The present study evaluates the current situation of LLST practices in patients with prolonged admission to the ICU who suffer worsening of their condition. A prospective, observational cohort study was carried out. Seventy-five Spanish ICUs. A total of 589 patients suffering 777 complications or adverse events with organ function impairment after day 7 of admission, during a three-month recruitment period. The timing of limitation, the subject proposing LLST, the degree of agreement within the team, the influence of LLST upon the doctor-patient-family relationship, and the way in which LLST is implemented. LLST was proposed in 34.3% of the patients presenting prolonged admission to the ICU with severe complications. The incidence was higher in patients with moderate to severe lung disease, cancer, immunosuppressive treatment or dependence for basic activities of daily living. LLST was finally implemented in 97% of the cases in which it was proposed. The decision within the medical team was unanimous in 87.9% of the cases. The doctor-patient-family relationship usually does not change or even improves in this situation. LLST in ICUs is usually carried out under unanimous decision of the medical team, is performed more frequently in patients with severe comorbidity, and usually does not have a negative impact upon the relationship with the patients and their families. Copyright © 2013 Elsevier España, S.L.U. and SEMICYUC. All rights reserved.

  18. Mobility Limitations and Fall-Related Factors Contribute to the Reduced Health-Related Quality of Life in Older Adults With Chronic Musculoskeletal Pain.

    Science.gov (United States)

    Stubbs, Brendon; Schofield, Pat; Patchay, Sandhi

    2016-01-01

    To investigate (1) the prevalence of chronic musculoskeletal pain (CMP) among a sample of community-dwelling older adults and (2) health-related quality of life (HRQOL) in people with CMP, particularly the association with mobility limitations and falls-related factors. Overall, 295 (response rate 73.5%) community-dwelling older adults were recruited across 10 sites. CMP was assessed using recognized criteria. In the sample of people with CMP, a hierarchical multiple regression analysis was conducted with HRQOL as the dependent variable and a number of independent variables were then inserted into the model. After controlling for demographic and medical variables, mobility (timed up and go (TUG), walking aid use, sedentary behavior) and fall-related factors (falls history, balance confidence, concerns about consequences of falling) were inserted into the model at the second step and changes in adjusted R(2) noted. Within our sample of older adults, 52% had CMP (154/295). Compared to the group without CMP of similar age (n = 141), those with CMP had reduced HRQOL and profound mobility limitations and more falls risk factors (P falls explanatory variables increased the variance explained within HRQOL from 14% to 36% (adjusted R(2) change 20%) in those with CMP. Sedentary behavior, pain interference, concerns about the consequences of falling, falls history, TUG scores, and balance confidence all remained significant predictors of HRQOL in the fully adjusted model in the CMP sample. Older adults with CMP have pronounced mobility limitations and increased falls risk factors, and these are associated with a marked reduction in HRQOL. Future prospective research is required to build on this cross-sectional study. © 2014 World Institute of Pain.

  19. Report on an Assessment of the Application of EPP Results from the Strain Limit Evaluation Procedure to the Prediction of Cyclic Life Based on the SMT Methodology

    Energy Technology Data Exchange (ETDEWEB)

    Jetter, R. I. [R. I. Jetter Consulting, Pebble Beach, CA (United States); Messner, M. C. [Argonne National Lab. (ANL), Argonne, IL (United States); Sham, T. -L. [Argonne National Lab. (ANL), Argonne, IL (United States); Wang, Y. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2017-08-01

    The goal of the proposed integrated Elastic Perfectly-Plastic (EPP) and Simplified Model Test (SMT) methodology is to incorporate an SMT data based approach for creep-fatigue damage evaluation into the EPP methodology to avoid the separate evaluation of creep and fatigue damage and eliminate the requirement for stress classification in current methods; thus greatly simplifying evaluation of elevated temperature cyclic service. This methodology should minimize over-conservatism while properly accounting for localized defects and stress risers. To support the implementation of the proposed methodology and to verify the applicability of the code rules, analytical studies and evaluation of thermomechanical test results continued in FY17. This report presents the results of those studies. An EPP strain limits methodology assessment was based on recent two-bar thermal ratcheting test results on 316H stainless steel in the temperature range of 405 to 7050C. Strain range predictions from the EPP evaluation of the two-bar tests were also evaluated and compared with the experimental results. The role of sustained primary loading on cyclic life was assessed using the results of pressurized SMT data from tests on Alloy 617 at 9500C. A viscoplastic material model was used in an analytic simulation of two-bar tests to compare with EPP strain limits assessments using isochronous stress strain curves that are consistent with the viscoplastic material model. A finite element model of a prior 304H stainless steel Oak Ridge National Laboratory (ORNL) nozzle-to-sphere test was developed and used for an EPP strain limits and creep-fatigue code case damage evaluations. A theoretical treatment of a recurring issue with convergence criteria for plastic shakedown illustrated the role of computer machine precision in EPP calculations.

  20. Measuring health-related quality of life in patients with mild to moderate eczema and psoriasis: clinical validity, reliability and sensitivity to change of the DLQI. The Cavide Research Group.

    Science.gov (United States)

    Badia, X; Mascaró, J M; Lozano, R

    1999-10-01

    The aim of this study was to assess the feasibility, validity, reliability and sensitivity to change of a Spanish version of the Dermatology Life Quality Index (DLQI) in patients with mild to moderate eczema and psoriasis who were treated with topical corticosteroids. The final study sample comprised 237 patients (48% eczema). Discriminant validity was tested by comparing patients' scores with those of a random sample of the general population (n = 100), and convergent validity by analysing correlations between DLQI scores, measures of clinical severity, and domain scores on the Nottingham Health Profile (NHP). Internal consistency and test-retest reliability were tested in clinically stable patients (n = 94), and responsiveness in a clinically unstable group (n = 143) initiating treatment with topical corticosteroids. Patient scores were significantly higher than general population scores (4.3 vs. 0. 27, P effect size for the total group of de novo patients = 0.70), though the great majority of changes occurred in items 1 and 2. The NHP Emotional Reactions and Mobility domains were more responsive than some DLQI domains. In clinical trials of treatments for mild to moderate eczema and psoriasis, it is likely that only items 1 and 2 of the DLQI will be needed, and it is probably advisable to include generic instruments alongside the DLQI.

  1. Proof tests on reliability

    International Nuclear Information System (INIS)

    Mishima, Yoshitsugu

    1983-01-01

    In order to obtain public understanding on nuclear power plants, tests should be carried out to prove the reliability and safety of present LWR plants. For example, the aseismicity of nuclear power plants must be verified by using a large scale earthquake simulator. Reliability test began in fiscal 1975, and the proof tests on steam generators and on PWR support and flexure pins against stress corrosion cracking have already been completed, and the results have been internationally highly appreciated. The capacity factor of the nuclear power plant operation in Japan rose to 80% in the summer of 1983, and considering the period of regular inspection, it means the operation of almost full capacity. Japanese LWR technology has now risen to the top place in the world after having overcome the defects. The significance of the reliability test is to secure the functioning till the age limit is reached, to confirm the correct forecast of deteriorating process, to confirm the effectiveness of the remedy to defects and to confirm the accuracy of predicting the behavior of facilities. The reliability of nuclear valves, fuel assemblies, the heat affected zones in welding, reactor cooling pumps and electric instruments has been tested or is being tested. (Kako, I.)

  2. Reliability analysis and risk-based methods for planning of operation & maintenance of offshore wind turbines

    DEFF Research Database (Denmark)

    Sørensen, John Dalsgaard

    2017-01-01

    for extreme and fatigue limit states are presented. Operation & Maintenance planning often follows corrective and preventive strategies based on information from condition monitoring and structural health monitoring systems. A reliability- and risk-based approach is presented where a life-cycle approach...

  3. Chronic early life stress induced by limited bedding and nesting (LBN) material in rodents: critical considerations of methodology, outcomes and translational potential.

    Science.gov (United States)

    Walker, Claire-Dominique; Bath, Kevin G; Joels, Marian; Korosi, Aniko; Larauche, Muriel; Lucassen, Paul J; Morris, Margaret J; Raineki, Charlis; Roth, Tania L; Sullivan, Regina M; Taché, Yvette; Baram, Tallie Z

    2017-09-01

    The immediate and long-term effects of exposure to early life stress (ELS) have been documented in humans and animal models. Even relatively brief periods of stress during the first 10 days of life in rodents can impact later behavioral regulation and the vulnerability to develop adult pathologies, in particular an impairment of cognitive functions and neurogenesis, but also modified social, emotional, and conditioned fear responses. The development of preclinical models of ELS exposure allows the examination of mechanisms and testing of therapeutic approaches that are not possible in humans. Here, we describe limited bedding and nesting (LBN) procedures, with models that produce altered maternal behavior ranging from fragmentation of care to maltreatment of infants. The purpose of this paper is to discuss important issues related to the implementation of this chronic ELS procedure and to describe some of the most prominent endpoints and consequences, focusing on areas of convergence between laboratories. Effects on the hypothalamic-pituitary adrenal (HPA) axis, gut axis and metabolism are presented in addition to changes in cognitive and emotional functions. Interestingly, recent data have suggested a strong sex difference in some of the reported consequences of the LBN paradigm, with females being more resilient in general than males. As both the chronic and intermittent variants of the LBN procedure have profound consequences on the offspring with minimal external intervention from the investigator, this model is advantageous ecologically and has a large translational potential. In addition to the direct effect of ELS on neurodevelopmental outcomes, exposure to adverse early environments can also have intergenerational impacts on mental health and function in subsequent generation offspring. Thus, advancing our understanding of the effect of ELS on brain and behavioral development is of critical concern for the health and wellbeing of both the current

  4. Providers with Limited Experience Perform Better in Advanced Life Support with Assistance Using an Interactive Device with an Automated External Defibrillator Linked to a Ventilator.

    Science.gov (United States)

    Busch, Christian Werner; Qalanawi, Mohammed; Kersten, Jan Felix; Kalwa, Tobias Johannes; Scotti, Norman Alexander; Reip, Wikhart; Doehn, Christoph; Maisch, Stefan; Nitzschke, Rainer

    2015-10-01

    Medical teams with limited experience in performing advanced life support (ALS) or with a low frequency of cardiopulmonary resuscitation (CPR) while on duty, often have difficulty complying with CPR guidelines. This study evaluated whether the quality of CPR of trained medical students, who served as an example of teams with limited experience in ALS, could be improved with device assistance. The primary outcome was the hands-off time (i.e., the percentage of the entire CPR time without chest compressions). The secondary outcome was seven time intervals, which should be as short as possible, and the quality of ventilations and chest compressions on the mannequin. We compared standard CPR equipment to an interactive device with visual and acoustic instructions for ALS workflow measures to guide briefly trained medical students through the ALS algorithm in a full-scale mannequin simulation study with a randomized crossover study design. The study equipment consisted of an automatic external defibrillator and ventilator that were electronically linked and communicating as a single system. Included were regular medical students in the third to sixth years of medical school of one class who provided written informed consent for voluntary participation and for the analysis of their CPR performance data. No exclusion criteria were applied. For statistical measures of evaluation we used an analysis of variance for crossover trials accounting for treatment effect, sequence effect, and carry-over effect, with adjustment for prior practical experience of the participants. Forty-two medical students participated in 21 CPR sessions, each using the standard and study equipment. Regarding the primary end point, the study equipment reduced the hands-off time from 40.1% (95% confidence interval [CI] 36.9-43.4%) to 35.6% (95% CI 32.4-38.9%, p = 0.031) compared with the standard equipment. Within the prespecified secondary end points, study equipment reduced the time interval until

  5. Association of Accelerometry-Measured Physical Activity and Cardiovascular Events in Mobility-Limited Older Adults: The LIFE (Lifestyle Interventions and Independence for Elders) Study.

    Science.gov (United States)

    Cochrane, Shannon K; Chen, Shyh-Huei; Fitzgerald, Jodi D; Dodson, John A; Fielding, Roger A; King, Abby C; McDermott, Mary M; Manini, Todd M; Marsh, Anthony P; Newman, Anne B; Pahor, Marco; Tudor-Locke, Catrine; Ambrosius, Walter T; Buford, Thomas W

    2017-12-02

    Data are sparse regarding the value of physical activity (PA) surveillance among older adults-particularly among those with mobility limitations. The objective of this study was to examine longitudinal associations between objectively measured daily PA and the incidence of cardiovascular events among older adults in the LIFE (Lifestyle Interventions and Independence for Elders) study. Cardiovascular events were adjudicated based on medical records review, and cardiovascular risk factors were controlled for in the analysis. Home-based activity data were collected by hip-worn accelerometers at baseline and at 6, 12, and 24 months postrandomization to either a physical activity or health education intervention. LIFE study participants (n=1590; age 78.9±5.2 [SD] years; 67.2% women) at baseline had an 11% lower incidence of experiencing a subsequent cardiovascular event per 500 steps taken per day based on activity data (hazard ratio, 0.89; 95% confidence interval, 0.84-0.96; P =0.001). At baseline, every 30 minutes spent performing activities ≥500 counts per minute (hazard ratio, 0.75; confidence interval, 0.65-0.89 [ P =0.001]) were also associated with a lower incidence of cardiovascular events. Throughout follow-up (6, 12, and 24 months), both the number of steps per day (per 500 steps; hazard ratio, 0.90, confidence interval, 0.85-0.96 [ P =0.001]) and duration of activity ≥500 counts per minute (per 30 minutes; hazard ratio, 0.76; confidence interval, 0.63-0.90 [ P =0.002]) were significantly associated with lower cardiovascular event rates. Objective measurements of physical activity via accelerometry were associated with cardiovascular events among older adults with limited mobility (summary score >10 on the Short Physical Performance Battery) both using baseline and longitudinal data. URL: http://www.clinicaltrials.gov. Unique identifier: NCT01072500. © 2017 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley.

  6. 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

  7. The effect of an outdoor activities' intervention delivered by older volunteers on the quality of life of older people with severe mobility limitations: a randomized controlled trial.

    Science.gov (United States)

    Rantanen, Taina; Äyräväinen, Irma; Eronen, Johanna; Lyyra, Tiinamari; Törmäkangas, Timo; Vaarama, Marja; Rantakokko, Merja

    2015-04-01

    Older community-living disabled people often have unmet activity needs and participation restrictions potentially reducing their quality of life (QoL). We examined the effects of an individualized out-of-home activity intervention delivered by volunteers on QoL among community-living older people, who have difficulty accessing the outdoors independently. Volunteering, Access to Outdoor Activities and Wellbeing in Older People (VOW; ISRCTN56847832) was a two-arm randomized single-blinded, controlled effectiveness trial (RCT) in Jyväskylä, Finland. The inclusion criteria were: age 65 or over, severe mobility limitation, able to communicate, and agree to participate in a RCT. Each intervention group member was assigned a trained volunteer with whom out-of-home activities were done once a week for 3 months (e.g., running errands or recreational activities). The primary outcome was the environmental subscore of QoL assessed with WHOQOL-BREF. Secondary outcomes were the overall QoL, physical capacity, psychological well-being, and social relationships assessed with WHOQOL_BREF and lower-extremity performance assessed with Short Physical Performance Battery (SPPB). 121 people aged 67-92 years (mean age 81.9 years, SD 5.9, 90 % women) were randomized. No treatment effect on the environmental QoL subscore was observed, but for physical capacity subscore a significant treatment effect was observed (General Linear Model, Group by Time p = 0.001). No effects were observed for the other QoL subscores or for SPPB score. This study suggests that individualized out-of-home activity intervention delivered by volunteers may influence the QoL of old severely mobility-limited community-living people in a positive way. Further studies are needed to better understand how to improve QoL of older disabled community-living people and potentially buffer them against more severe care needs and institutionalization.

  8. 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...... 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...

  9. Towards a strategy of reliable fusion first-wall design

    International Nuclear Information System (INIS)

    Schultz, J.H.

    1981-05-01

    Fusion first walls are subject to a large number of possible failure mechanisms, including erosion due to sputtering, arcing, blistering and vaporization and crack growth due to thermal and magnetic stresses. Each of these failure mechanisms is poorly characterized and has the potential of being severe. A strategy for designing reliably in the face of great uncertainty is discussed. Topological features beneficial to reactor availability are identified. The integration of limiter pumping with rf wave launching is discussed, as a means of simplifying reactor design. The concept of a sewer limiter is introduced, as a possible long-life limiter topology. The concept of flexible armor is discussed, as a means of extending maximum life

  10. Reliability-Based Code Calibration

    DEFF Research Database (Denmark)

    Faber, M.H.; Sørensen, John Dalsgaard

    2003-01-01

    The present paper addresses fundamental concepts of reliability based code calibration. First basic principles of structural reliability theory are introduced and it is shown how the results of FORM based reliability analysis may be related to partial safety factors and characteristic values....... Thereafter the code calibration problem is presented in its principal decision theoretical form and it is discussed how acceptable levels of failure probability (or target reliabilities) may be established. Furthermore suggested values for acceptable annual failure probabilities are given for ultimate...... and serviceability limit states. Finally the paper describes the Joint Committee on Structural Safety (JCSS) recommended procedure - CodeCal - for the practical implementation of reliability based code calibration of LRFD based design codes....

  11. Power peaking nuclear reliability factors

    International Nuclear Information System (INIS)

    Hassan, H.A.; Pegram, J.W.; Mays, C.W.; Romano, J.J.; Woods, J.J.; Warren, H.D.

    1977-11-01

    The Calculational Nuclear Reliability Factor (CNRF) assigned to the limiting power density calculated in reactor design has been determined. The CNRF is presented as a function of the relative power density of the fuel assembly and its radial local. In addition, the Measurement Nuclear Reliability Factor (MNRF) for the measured peak hot pellet power in the core has been evaluated. This MNRF is also presented as a function of the relative power density and radial local within the fuel assembly

  12. Risk assessment and reliability for low level radioactive waste disposal

    International Nuclear Information System (INIS)

    Gregory, P.O.; Jones, G.A.

    1986-01-01

    The reliability of critical design features at low-level radioactive waste disposal facilities is a major concern in the licensing of these structures. To date, no systematic methodology has been adopted to evaluate the geotechnical reliability of Uranium Mill Tailings Remedial Action (UMTRA) disposal facilities currently being designed and/or constructed. This paper discusses and critiques the deterministic methods currently used to evaluate UMTRA reliability. Because deterministic methods may not be applicable in some cases because of the unusually long design life of UMTRA facilities, it is proposed that a probabilistic risk assessment-based methodology be used as a secondary method to aid in the evaluating of geotechnical reliability of critical items. Similar methodologies have proven successful in evaluating the reliability of a variety of conventional earth structures. In this paper, an ''acceptable'' level of risk for UMTRA facilities is developed, an evaluation method is presented, and two example applications of the proposed methodology are provided for a generic UMTRA disposal facility. The proposed technique is shown to be a simple method which might be used to aid in reliability evaluations on a selective basis. Finally, other possible applications and the limitations of the proposed methodology are discussed

  13. As reliable as the sun

    Science.gov (United States)

    Leijtens, J. A. P.

    2017-11-01

    Fortunately there is almost nothing as reliable as the sun which can consequently be utilized as a very reliable source of spacecraft power. In order to harvest this power, the solar panels have to be pointed towards the sun as accurately and reliably as possible. To this extend, sunsensors are available on almost every satellite to support vital sun-pointing capability throughout the mission, even in the deployment and save mode phases of the satellites life. Given the criticality of the application one would expect that after more than 50 years of sun sensor utilisation, such sensors would be fully matured and optimised. In actual fact though, the majority of sunsensors employed are still coarse sunsensors which have a proven extreme reliability but present major issues regarding albedo sensitivity and pointing accuracy.

  14. Steam generator reliability improvement project

    International Nuclear Information System (INIS)

    Blomgren, J.C.; Green, S.J.

    1987-01-01

    Upon successful completion of its research and development technology transfer program, the Electric Power Research Institute's Steam Generator Owners Group (SGOG II) will disband in December 1986 and be replaced in January 1987 by a successor project, the Steam Generator Reliability Project (SGRP). The new project, funded in the EPRI base program, will continue the emphasis on reliability and life extension that was carried forward by SGOG II. The objectives of SGOG II have been met. Causes and remedies have been identified for tubing corrosion problems, such as stress corrosion cracking and pitting, and steam generator technology has been improved in areas such as tube wear prediction and nondestructive evaluation (NDE). These actions have led to improved reliability of steam generators. Now the owners want to continue with a centrally managed program that builds on what has been learned. The goal is to continue to improve steam generator reliability and solve small problems before they become large problems

  15. Steam generator reliability improvement project

    International Nuclear Information System (INIS)

    Blomgren, J.C.; Green, S.J.

    1987-01-01

    Upon successful completion of its research and development technology transfer program, the Electric Power Research Institute's (EPRI's) Steam Generator Owners Group (SGOG II) will disband in December 1986, and be replaced in January 1987, by a successor project, the Steam Generator Reliability Project (SGRP). The new project, funded in the EPRI base program, will continue to emphasize reliability and life extension, which were carried forward by SGOG II. The objectives of SGOG II have been met. Causes and remedies have been identified for tubing corrosion problems such as stress corrosion cracking and pitting, and steam generator technology has been improved in areas such as tube wear prediction and nondestructive evaluation. These actions have led to improved reliability of steam generators. Now the owners want to continue with a centrally managed program that builds on what has been learned. The goal is to continue to improve steam generator reliability and to solve small problems before they become large problems

  16. Cross-cultural adaptation, reliability and validity of the Spanish version of the Quality of Life in Adult Cancer Survivors (QLACS) questionnaire: application in a sample of short-term survivors.

    Science.gov (United States)

    Escobar, Antonio; Trujillo-Martín, Maria del Mar; Rueda, Antonio; Pérez-Ruiz, Elisabeth; Avis, Nancy E; Bilbao, Amaia

    2015-11-16

    The aim of this study was to validate the Quality of Life in Adult Cancer Survivors (QLACS) in short-term Spanish cancer survivor's patients. Patients with breast, colorectal or prostate cancer that had finished their initial cancer treatment 3 years before the beginning of this study completed QLACS, WHOQOL, Short Form-36, Hospital Anxiety and Depression Scale, EORTC-QLQ-BR23 and EQ-5D. Cultural adaptation was made based on established guidelines. Reliability was evaluated using internal consistency and test-retest. Convergent validity was studied by mean of Pearson's correlation coefficient. Structural validity was determined by a second-order confirmatory factor analysis (CFA) and Rasch analysis was used to assess the unidimensionality of the Generic and Cancer-specific scales. Cronbach's alpha were above 0.7 in all domains and summary scales. Test-retest coefficients were 0.88 for Generic and 0.82 for Cancer-specific summary scales. QLACS generic summary scale was correlated with other generic criterion measures, SF-36 MCS (r = - 0.74) and EQ-VAS (r = - 0.63). QLACS cancer-specific scale had lower values with the same constructs. CFA provided satisfactory fit indices in all cases. The RMSEA value was 0.061 and CFI and TLI values were 0.929 and 0.925, respectively. All factor loadings were higher than 0.40 and statistically significant (P validity and reliability of QLACS questionnaire to be used in short-term cancer survivors.

  17. System Reliability Engineering

    International Nuclear Information System (INIS)

    Lim, Tae Jin

    2005-02-01

    This book tells of reliability engineering, which includes quality and reliability, reliability data, importance of reliability engineering, reliability and measure, the poisson process like goodness of fit test and the poisson arrival model, reliability estimation like exponential distribution, reliability of systems, availability, preventive maintenance such as replacement policies, minimal repair policy, shock models, spares, group maintenance and periodic inspection, analysis of common cause failure, and analysis model of repair effect.

  18. RTE - Reliability report 2016

    International Nuclear Information System (INIS)

    2017-06-01

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

  19. Development of a post-intensive care unit storytelling intervention for surrogates involved in decisions to limit life-sustaining treatment.

    Science.gov (United States)

    Schenker, Yael; Dew, Mary Amanda; Reynolds, Charles F; Arnold, Robert M; Tiver, Greer A; Barnato, Amber E

    2015-06-01

    Surrogates involved in decisions to limit life-sustaining treatment for a loved one in the intensive care unit (ICU) are at increased risk for adverse psychological outcomes that can last for months to years after the ICU experience. Post-ICU interventions to reduce surrogate distress have not yet been developed. We sought to (1) describe a conceptual framework underlying the beneficial mental health effects of storytelling, and (2) present formative work developing a storytelling intervention to reduce distress for recently bereaved surrogates. An interdisciplinary team conceived the idea for a storytelling intervention based on evidence from narrative theory that storytelling reduces distress from traumatic events through emotional disclosure, cognitive processing, and social connection. We developed an initial storytelling guide based on this theory and the clinical perspectives of team members. We then conducted a case series with recently bereaved surrogates to iteratively test and modify the guide. The storytelling guide covered three key domains of the surrogate's experience of the patient's illness and death: antecedents, ICU experience, and aftermath. The facilitator focused on the parts of a story that appeared to generate strong emotions and used nonjudgmental statements to attend to these emotions. Between September 2012 and May 2013, we identified 28 eligible surrogates from a medical ICU and consented 20 for medical record review and recontact; 10 became eligible, of whom 6 consented and completed the storytelling intervention. The single-session storytelling intervention lasted from 40 to 92 minutes. All storytelling participants endorsed the intervention as acceptable, and five of six reported it as helpful. Surrogate storytelling is an innovative and acceptable post-ICU intervention for recently bereaved surrogates and should be evaluated further.

  20. Feasibility, reliability, and validity of the Pediatric Quality of Life Inventory ™ generic core scales, cancer module, and multidimensional fatigue scale in long-term adult survivors of pediatric cancer.

    Science.gov (United States)

    Robert, Rhonda S; Paxton, Raheem J; Palla, Shana L; Yang, Grace; Askins, Martha A; Joy, Shaini E; Ater, Joann L

    2012-10-01

    Most health-related quality of life assessments are designed for either children or adults and have not been evaluated for adolescent and young adult survivors of pediatric cancer. The objective of this study was to examine the feasibility, reliability, and validity of the Pediatric Quality of Life Inventory (PedsQL ™ Generic Core Scales, Cancer Module, and Multidimensional Fatigue Scale in adult survivors of pediatric cancer. Adult survivors (n = 64; Mean age 35 year old; >2 years after treatment) completed the PedsQL™ Generic Core Scales, Cancer Module, and Multidimensional Fatigue Scale. Feasibility was examined with floor and ceiling effects; and internal consistency was determined by Cronbach's coefficient alpha calculations. Inter-factor correlations were also assessed. Significant ceiling effects were observed for the scales of social function, nausea, procedural anxiety, treatment anxiety, and communication. Internal consistency for all subscales was within the recommended ranges (α ≥ 0.70). Moderate to strong correlations between most Cancer Module and Generic Core Scales (r = 0.25 to r = 0.76) and between the Multidimensional Fatigue Scale and Generic Core Scales (r = 0.37 to r = 0.73). The PedsQL™ Generic Core Scales, Cancer Module, and Multidimensional Fatigue Scale appear to be feasible for an older population of pediatric cancer survivors; however, some of the Cancer Module Scales (nausea, procedural/treatment anxiety, and communication) were deemed not relevant for long-term survivors. More information is needed to determine whether the issues addressed by these modules are meaningful to long-term adult survivors of pediatric cancers. Copyright © 2012 Wiley Periodicals, Inc.

  1. Introduction to quality and reliability engineering

    CERN Document Server

    Jiang, Renyan

    2015-01-01

    This book presents the state-of-the-art in quality and reliability engineering from a product life cycle standpoint. Topics in reliability include reliability models, life data analysis and modeling, design for reliability and accelerated life testing, while topics in quality include design for quality, acceptance sampling and supplier selection, statistical process control, production tests such as screening and burn-in, warranty and maintenance. The book provides comprehensive insights into two closely related subjects, and includes a wealth of examples and problems to enhance reader comprehension and link theory and practice. All numerical examples can be easily solved using Microsoft Excel. The book is intended for senior undergraduate and post-graduate students in related engineering and management programs such as mechanical engineering, manufacturing engineering, industrial engineering and engineering management programs, as well as for researchers and engineers in the quality and reliability fields. D...

  2. Turbomachine Sealing and Secondary Flows - Part 3. Part 3; Review of Power-Stream Support, Unsteady Flow Systems, Seal and Disk Cavity Flows, Engine Externals, and Life and Reliability Issues

    Science.gov (United States)

    Hendricks, R. C.; Steinetz, B. M.; Zaretsky, E. V.; Athavale, M. M.; Przekwas, A. J.

    2004-01-01

    The issues and components supporting the engine power stream are reviewed. It is essential that companies pay close attention to engine sealing issues, particularly on the high-pressure spool or high-pressure pumps. Small changes in these systems are reflected throughout the entire engine. Although cavity, platform, and tip sealing are complex and have a significant effect on component and engine performance, computational tools (e.g., NASA-developed INDSEAL, SCISEAL, and ADPAC) are available to help guide the designer and the experimenter. Gas turbine engine and rocket engine externals must all function efficiently with a high degree of reliability in order for the engine to run but often receive little attention until they malfunction. Within the open literature statistically significant data for critical engine components are virtually nonexistent; the classic approach is deterministic. Studies show that variations with loading can have a significant effect on component performance and life. Without validation data they are just studies. These variations and deficits in statistical databases require immediate attention.

  3. RELIABILITY OF MACHINE ELEMENTS IN WIND TURBINES

    Directory of Open Access Journals (Sweden)

    Willi GRUENDER

    2010-06-01

    Full Text Available Worldwide electrical energy production generated by wind turbines grows at a rate of 30 percent. This doubles the total production every three years. At the same time the power of individual stations goes up by 20 percent annually. Whereas today the towers, rotors and drive trains have to handle 5 MW, in about six to eight years they might produce up to fifteen MW. As a consequence, enormous pressure is put on the wind turbine manufacturers, the component suppliers and the operators. And because prototype and field testing is limited by its expense, the design of new turbines demands thorough analysis and simulation. Looking at the critical components of a wind turbine this paper describes advanced design tools which help to anticipate failures, but also assists in optimizing reliability and service life. Development of the software tools has been supported by research activities in many universities.

  4. AMSAA Reliability Growth Guide

    National Research Council Canada - National Science Library

    Broemm, William

    2000-01-01

    ... has developed reliability growth methodology for all phases of the process, from planning to tracking to projection. The report presents this methodology and associated reliability growth concepts.

  5. Reliability analysis of shutdown system

    International Nuclear Information System (INIS)

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

    2005-01-01

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

  6. Reliability issues at the LHC

    CERN Multimedia

    CERN. Geneva. Audiovisual Unit; Gillies, James D

    2002-01-01

    The Lectures on reliability issues at the LHC will be focused on five main Modules on five days. Module 1: Basic Elements in Reliability Engineering Some basic terms, definitions and methods, from components up to the system and the plant, common cause failures and human factor issues. Module 2: Interrelations of Reliability & Safety (R&S) Reliability and risk informed approach, living models, risk monitoring. Module 3: The ideal R&S Process for Large Scale Systems From R&S goals via the implementation into the system to the proof of the compliance. Module 4: Some Applications of R&S on LHC Master logic, anatomy of risk, cause - consequence diagram, decomposition and aggregation of the system. Module 5: Lessons learned from R&S Application in various Technologies Success stories, pitfalls, constrains in data and methods, limitations per se, experienced in aviation, space, process, nuclear, offshore and transport systems and plants. The Lectures will reflect in summary the compromise in...

  7. Reliability and Maintainability (RAM) Training

    Science.gov (United States)

    Lalli, Vincent R. (Editor); Malec, Henry A. (Editor); Packard, Michael H. (Editor)

    2000-01-01

    The theme of this manual is failure physics-the study of how products, hardware, software, and systems fail and what can be done about it. The intent is to impart useful information, to extend the limits of production capability, and to assist in achieving low-cost reliable products. In a broader sense the manual should do more. It should underscore the urgent need CI for mature attitudes toward reliability. Five of the chapters were originally presented as a classroom course to over 1000 Martin Marietta engineers and technicians. Another four chapters and three appendixes have been added, We begin with a view of reliability from the years 1940 to 2000. Chapter 2 starts the training material with a review of mathematics and a description of what elements contribute to product failures. The remaining chapters elucidate basic reliability theory and the disciplines that allow us to control and eliminate failures.

  8. 24. MPA-seminar: safety and reliability of plant technology with special emphasis on integrity and life management. Vol. 1. Papers 1-27; 24. MPA-Seminar: Sicherheit und Verfuegbarkeit in der Anlagentechnik mit dem Schwerpunkt Integritaet und Lebensdauermanagement. Bd. 1. Vortraege 1-27

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1999-08-01

    The first volume is dedicated to the safety and reliability of plant technology with special emphasis on the integrity and life management. The main topic in the volume is the contribution of nondestructive testing to the reactor safety from an international point of view. All 20 papers are separately analyzed for this database. (orig.)

  9. Pulse shape analysis for the GERDA experiment to set a new limit on the half-life of 0νββ decay of {sup 76}Ge

    Energy Technology Data Exchange (ETDEWEB)

    Wagner, Victoria Elisabeth

    2017-01-25

    The GERDA experiment searches for neutrinoless double beta (0νββ) decay of {sup 76}Ge using high purity germanium (HPGe) detectors operated in liquid argon (LAr). The aim is to explore half-lives of the order of 10{sup 26} yr. Therefore, GERDA relies on improved active background reduction techniques such as pulse shape discrimination (PSD) in which the time structure of the germanium signals is analyzed to discriminate signal- from background-like events. Two types of HPGe detectors are operated: semi-coaxial detectors previously used in the Heidelberg-Moscow and IGEX experiments and new Broad Energy Germanium (BEGe) detectors which feature an improved energy resolution and enhanced PSD. In Phase I of the experiment, five enriched BEGe detectors were used for the first time in the search for 0νββ decay. A PSD based on a single parameter, the ratio of the maximum current amplitude over the energy A/E is applied. 83% of the background events in a 232 keV region around Q{sub ββ} are rejected with a high signal efficiency of (92.1 ± 1.9) %. The achieved background index (BI) is (5.4{sup +4.1}{sub -3.4}) . 10{sup -3} (counts)/(keV.kg.yr). This is an improvement by a factor of 10 compared to previous germanium based 0νββ experiments. Phase II of the experiment includes a major upgrade: for further background rejection, the LAr cryostat is instrumented to detect argon scintillation light. Additional 25 BEGe detectors are installed. After PSD and LAr veto a BI of (0.7{sup +1.3}{sub -0.5}) . 10{sup -3} (counts)/(keV.kg.yr) is achieved. This is the best BI achieved in 0νββ experiments so far. A frequentist statistical analysis is performed on the combined data collected in GERDA Phase I and the first Phase II release. A new limit on the half-life of 0νββ decay of {sup 76}Ge is set to T{sup 0ν}{sub 1/2}>5.3.10{sup 25} yr at 90% C.L., with a median sensitivity of T{sup 0ν}{sub 1/2}>4.0.10{sup 25} yr at 90% C.L.

  10. A reliability simulation language for reliability analysis

    International Nuclear Information System (INIS)

    Deans, N.D.; Miller, A.J.; Mann, D.P.

    1986-01-01

    The results of work being undertaken to develop a Reliability Description Language (RDL) which will enable reliability analysts to describe complex reliability problems in a simple, clear and unambiguous way are described. Component and system features can be stated in a formal manner and subsequently used, along with control statements to form a structured program. The program can be compiled and executed on a general-purpose computer or special-purpose simulator. (DG)

  11. Fatigue Reliability under Random Loads

    DEFF Research Database (Denmark)

    Talreja, R.

    1979-01-01

    We consider the problem of estimating the probability of survival (non-failure) and the probability of safe operation (strength greater than a limiting value) of structures subjected to random loads. These probabilities are formulated in terms of the probability distributions of the loads...... propagation stage. The consequences of this behaviour on the fatigue reliability are discussed....

  12. Equipment Reliability Program in NPP Krsko

    International Nuclear Information System (INIS)

    Skaler, F.; Djetelic, N.

    2006-01-01

    Operation that is safe, reliable, effective and acceptable to public is the common message in a mission statement of commercial nuclear power plants (NPPs). To fulfill these goals, nuclear industry, among other areas, has to focus on: 1 Human Performance (HU) and 2 Equipment Reliability (EQ). The performance objective of HU is as follows: The behaviors of all personnel result in safe and reliable station operation. While unwanted human behaviors in operations mostly result directly in the event, the behavior flaws either in the area of maintenance or engineering usually cause decreased equipment reliability. Unsatisfied Human performance leads even the best designed power plants into significant operating events, which can be found as well-known examples in nuclear industry. Equipment reliability is today recognized as the key to success. While the human performance at most NPPs has been improving since the start of WANO / INPO / IAEA evaluations, the open energy market has forced the nuclear plants to reduce production costs and operate more reliably and effectively. The balance between these two (opposite) goals has made equipment reliability even more important for safe, reliable and efficient production. Insisting on on-line operation by ignoring some principles of safety could nowadays in a well-developed safety culture and human performance environment exceed the cost of electricity losses. In last decade the leading USA nuclear companies put a lot of effort to improve equipment reliability primarily based on INPO Equipment Reliability Program AP-913 at their NPP stations. The Equipment Reliability Program is the key program not only for safe and reliable operation, but also for the Life Cycle Management and Aging Management on the way to the nuclear power plant life extension. The purpose of Equipment Reliability process is to identify, organize, integrate and coordinate equipment reliability activities (preventive and predictive maintenance, maintenance

  13. Reliability Modeling of Wind Turbines

    DEFF Research Database (Denmark)

    Kostandyan, Erik

    Cost reductions for offshore wind turbines are a substantial requirement in order to make offshore wind energy more competitive compared to other energy supply methods. During the 20 – 25 years of wind turbines useful life, Operation & Maintenance costs are typically estimated to be a quarter...... for Operation & Maintenance planning. Concentrating efforts on development of such models, this research is focused on reliability modeling of Wind Turbine critical subsystems (especially the power converter system). For reliability assessment of these components, structural reliability methods are applied...... to one third of the total cost of energy. Reduction of Operation & Maintenance costs will result in significant cost savings and result in cheaper electricity production. Operation & Maintenance processes mainly involve actions related to replacements or repair. Identifying the right times when...

  14. Component reliability for electronic systems

    CERN Document Server

    Bajenescu, Titu-Marius I

    2010-01-01

    The main reason for the premature breakdown of today's electronic products (computers, cars, tools, appliances, etc.) is the failure of the components used to build these products. Today professionals are looking for effective ways to minimize the degradation of electronic components to help ensure longer-lasting, more technically sound products and systems. This practical book offers engineers specific guidance on how to design more reliable components and build more reliable electronic systems. Professionals learn how to optimize a virtual component prototype, accurately monitor product reliability during the entire production process, and add the burn-in and selection procedures that are the most appropriate for the intended applications. Moreover, the book helps system designers ensure that all components are correctly applied, margins are adequate, wear-out failure modes are prevented during the expected duration of life, and system interfaces cannot lead to failure.

  15. Fundamentals and applications of systems reliability analysis

    International Nuclear Information System (INIS)

    Boesebeck, K.; Heuser, F.W.; Kotthoff, K.

    1976-01-01

    The lecture gives a survey on the application of methods of reliability analysis to assess the safety of nuclear power plants. Possible statements of reliability analysis in connection with specifications of the atomic licensing procedure are especially dealt with. Existing specifications of safety criteria are additionally discussed with the help of reliability analysis by the example of the reliability analysis of a reactor protection system. Beyond the limited application to single safety systems, the significance of reliability analysis for a closed risk concept is explained in the last part of the lecture. (orig./LH) [de

  16. RELIABILITY OF LENTICULAR EXPANSION COMPENSATORS

    Directory of Open Access Journals (Sweden)

    Gabriel BURLACU,

    2011-11-01

    Full Text Available Axial lenticular compensators are made to take over the longitudinal heat expansion, shock , vibration and noise, made elastic connections for piping systems. In order to have a long life for installations it is necessary that all elements, including lenticular compensators, have a good reliability. This desire can be did by technology of manufactoring and assembly of compensators, the material for lenses and by maintenance.of compensator

  17. Guarantee of reliability of devices complexes for plastic tube welding

    International Nuclear Information System (INIS)

    Voskresenskij, L.A.; Zajtsev, A.I.; Nelyubov, V.I.; Fedorov, M.A.

    1988-01-01

    Results of calculations and experimental studies on providing reliability of complex for plastic tube welding are presented. Choice of reliability indeces and standards is based. Reliability levels of components are determined. The most waded details are calculated. It is shown that they meet the reqrurements of strength and reliability. Service life tests supported the correct choice of springs. Recommendations on elevating reliability are given. Directions of further developments are shown. 8 refs.; 2 figs.; 1 tab

  18. Can they recover? An assessment of adult adjustment problems among males in the abstainer, recovery, life-course persistent, and adolescence-limited pathways followed up to age 56 in the Cambridge Study in Delinquent Development.

    Science.gov (United States)

    Jennings, Wesley G; Rocque, Michael; Fox, Bryanna Hahn; Piquero, Alex R; Farrington, David P

    2016-05-01

    Much research has examined Moffitt's developmental taxonomy, focusing almost exclusively on the distinction between life-course persistent and adolescence-limited offenders. Of interest, a handful of studies have identified a group of individuals whose early childhood years were marked by extensive antisocial behavior but who seemed to recover and desist (at least from severe offending) in adolescence and early adulthood. We use data from the Cambridge Study in Delinquent Development to examine the adult adjustment outcomes of different groups of offenders, including a recoveries group, in late middle adulthood, offering the most comprehensive investigation of this particular group to date. Findings indicate that abstainers comprise the largest group of males followed by adolescence-limited offenders, recoveries, and life-course persistent offenders. Furthermore, the results reveal that a host of adult adjustment problems measured at ages 32 and 48 in a number of life-course domains are differentially distributed across these four offender groups. In addition, the recoveries and life-course persistent offenders often show the greatest number of adult adjustment problems relative to the adolescence-limited offenders and abstainers.

  19. Transmission reliability faces future challenges

    International Nuclear Information System (INIS)

    Beaty, W.

    1993-01-01

    The recently published Washington International Energy Group's 1993 Electric Utility Outlook states that nearly one-third (31 percent) of U.S. utility executives expect reliability to decrease in the near future. Electric power system stability is crucial to reliability. Stability analysis determines whether a system will stay intact under normal operating conditions, during minor disturbances such as load fluctuations, and during major disturbances when one or more parts of the system fails. All system elements contribute to reliability or the lack of it. However, this report centers on the transmission segment of the electric system. The North American Electric Reliability Council (NERC) says the transmission systems as planned will be adequate over the next 10 years. However, delays in building new lines and increasing demands for transmission services are serious concerns. Reliability concerns exist in the Mid-Continent Area Power Pool and the Mid-America Interconnected Network regions where transmission facilities have not been allowed to be constructed as planned. Portions of the transmission systems in other regions are loaded at or near their limits. NERC further states that utilities must be allowed to complete planned generation and transmission as scheduled. A reliable supply of electricity also depends on adhering to established operating criteria. Factors that could complicate operations include: More interchange schedules resulting from increased transmission services. Increased line loadings in portions of the transmission systems. Proliferation of non-utility generators

  20. Bridging the gap between metallurgy and fatigue reliability of hydraulic turbine runners

    International Nuclear Information System (INIS)

    Thibault, D; Gagnon, M; Godin, S

    2014-01-01

    The failure of hydraulic turbine runners is a very rare event. Hence, in order to assess the reliability of these components, one cannot rely on statistical models based on the number of failures in a given population. However, as there is a limited number of degradation mechanisms involved, it is possible to use physically-based reliability models. Such models are more complicated but have the advantage of being able to account for physical parameters in the prediction of the evolution of runner degradation. They can therefore propose solutions to help improve reliability. With the use of such models, the effect of materials properties on runner reliability can easily be illustrated. This paper will present a brief review of the Kitagawa-Takahashi diagram that links the damage tolerance approach, based on fracture mechanics, to the stress or strain-life approaches. This diagram is at the centre of the reliability model used in this study. Using simplified response spectra obtained from on-site runner stress measurements, the paper will show how fatigue reliability is impacted by materials fatigue properties, namely fatigue crack propagation behaviour and fatigue limit obtained on S-N curves. It will also present a review of the most important microstructural features of 13%Cr- 4%Ni stainless steels used for runner manufacturing and will review how they influence fatigue properties in an effort to bridge the gap between metallurgy and turbine runners reliability

  1. Reliability data banks

    International Nuclear Information System (INIS)

    Cannon, A.G.; Bendell, A.

    1991-01-01

    Following an introductory chapter on Reliability, what is it, why it is needed, how it is achieved and measured, the principles of reliability data bases and analysis methodologies are the subject of the next two chapters. Achievements due to the development of data banks are mentioned for different industries in the next chapter, FACTS, a comprehensive information system for industrial safety and reliability data collection in process plants are covered next. CREDO, the Central Reliability Data Organization is described in the next chapter and is indexed separately, as is the chapter on DANTE, the fabrication reliability Data analysis system. Reliability data banks at Electricite de France and IAEA's experience in compiling a generic component reliability data base are also separately indexed. The European reliability data system, ERDS, and the development of a large data bank come next. The last three chapters look at 'Reliability data banks, - friend foe or a waste of time'? and future developments. (UK)

  2. Suncor maintenance and reliability

    Energy Technology Data Exchange (ETDEWEB)

    Little, S. [Suncor Energy, Calgary, AB (Canada)

    2006-07-01

    Fleet maintenance and reliability at Suncor Energy was discussed in this presentation, with reference to Suncor Energy's primary and support equipment fleets. This paper also discussed Suncor Energy's maintenance and reliability standard involving people, processes and technology. An organizational maturity chart that graphed organizational learning against organizational performance was illustrated. The presentation also reviewed the maintenance and reliability framework; maintenance reliability model; the process overview of the maintenance and reliability standard; a process flow chart of maintenance strategies and programs; and an asset reliability improvement process flow chart. An example of an improvement initiative was included, with reference to a shovel reliability review; a dipper trip reliability investigation; bucket related failures by type and frequency; root cause analysis of the reliability process; and additional actions taken. Last, the presentation provided a graph of the results of the improvement initiative and presented the key lessons learned. tabs., figs.

  3. 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.

  4. The role of high cycle fatigue (HCF) onset in Francis runner reliability

    International Nuclear Information System (INIS)

    Gagnon, M; Tahan, S A; Bocher, P; Thibault, D

    2012-01-01

    High Cycle Fatigue (HCF) plays an important role in Francis runner reliability. This paper presents a model in which reliability is defined as the probability of not exceeding a threshold above which HCF contributes to crack propagation. In the context of combined Low Cycle Fatigue (LCF) and HCF loading, the Kitagawa diagram is used as the limit state threshold for reliability. The reliability problem is solved using First-Order Reliability Methods (FORM). A study case is proposed using in situ measured strains and operational data. All the parameters of the reliability problem are based either on observed data or on typical design specifications. From the results obtained, we observed that the uncertainty around the defect size and the HCF stress range play an important role in reliability. At the same time, we observed that expected values for the LCF stress range and the number of LCF cycles have a significant influence on life assessment, but the uncertainty around these values could be neglected in the reliability assessment.

  5. Reliability of the Fermilab Antiproton Source

    International Nuclear Information System (INIS)

    Harms, E. Jr.

    1993-05-01

    This paper reports on the reliability of the Fermilab Antiproton source since it began operation in 1985. Reliability of the complex as a whole as well as subsystem performance is summarized. Also discussed is the trending done to determine causes of significant machine downtime and actions taken to reduce the incidence of failure. Finally, results of a study to detect previously unidentified reliability limitations are presented

  6. Limitación del esfuerzo terapéutico versus eutanasia: una reflexión bioética Limiting life-sustaining medical treatment versus euthanasia: a bioethical reflection

    Directory of Open Access Journals (Sweden)

    Gilberto de Jesús Betancourt Betancourt

    2011-08-01

    Full Text Available La práctica de la limitación del esfuerzo terapéutico no es novedad en las unidades de atención al paciente grave. Es necesario diferenciar la eutanasia de la limitación del esfuerzo terapéutico, considerada esta última como una buena práctica clínica. En este trabajo se realiza una reflexión teórica que tiene como objetivo fundamental el análisis bioético acerca de las diferencias fundamentales entre ambas.The practice of limiting life-sustaining medical treatment is nothing new at intensive care units. Euthanasia should be distinguished from limiting life-sustaining medical treatments, which is considered as a good practice. This paper presents a theoretical reflection based on a bioethical analysis of the main differences between both of them.

  7. Reliable computation from contextual correlations

    Science.gov (United States)

    Oestereich, André L.; Galvão, Ernesto F.

    2017-12-01

    An operational approach to the study of computation based on correlations considers black boxes with one-bit inputs and outputs, controlled by a limited classical computer capable only of performing sums modulo-two. In this setting, it was shown that noncontextual correlations do not provide any extra computational power, while contextual correlations were found to be necessary for the deterministic evaluation of nonlinear Boolean functions. Here we investigate the requirements for reliable computation in this setting; that is, the evaluation of any Boolean function with success probability bounded away from 1 /2 . We show that bipartite CHSH quantum correlations suffice for reliable computation. We also prove that an arbitrarily small violation of a multipartite Greenberger-Horne-Zeilinger noncontextuality inequality also suffices for reliable computation.

  8. 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.

  9. Power electronics reliability analysis.

    Energy Technology Data Exchange (ETDEWEB)

    Smith, Mark A.; Atcitty, Stanley

    2009-12-01

    This report provides the DOE and industry with a general process for analyzing power electronics reliability. The analysis can help with understanding the main causes of failures, downtime, and cost and how to reduce them. One approach is to collect field maintenance data and use it directly to calculate reliability metrics related to each cause. Another approach is to model the functional structure of the equipment using a fault tree to derive system reliability from component reliability. Analysis of a fictitious device demonstrates the latter process. Optimization can use the resulting baseline model to decide how to improve reliability and/or lower costs. It is recommended that both electric utilities and equipment manufacturers make provisions to collect and share data in order to lay the groundwork for improving reliability into the future. Reliability analysis helps guide reliability improvements in hardware and software technology including condition monitoring and prognostics and health management.

  10. Reliability of software

    International Nuclear Information System (INIS)

    Kopetz, H.

    1980-01-01

    Common factors and differences in the reliability of hardware and software; reliability increase by means of methods of software redundancy. Maintenance of software for long term operating behavior. (HP) [de

  11. Life-cycle assessment of semiconductors

    CERN Document Server

    Boyd, Sarah B

    2012-01-01

    Life-Cycle Assessment of Semiconductors presents the first and thus far only available transparent and complete life cycle assessment of semiconductor devices. A lack of reliable semiconductor LCA data has been a major challenge to evaluation of the potential environmental benefits of information technologies (IT). The analysis and results presented in this book will allow a higher degree of confidence and certainty in decisions concerning the use of IT in efforts to reduce climate change and other environmental effects. Coverage includes but is not limited to semiconductor manufacturing trends by product type and geography, unique coverage of life-cycle assessment, with a focus on uncertainty and sensitivity analysis of energy and global warming missions for CMOS logic devices, life cycle assessment of flash memory and life cycle assessment of DRAM. The information and conclusions discussed here will be highly relevant and useful to individuals and institutions. The book also: Provides a detailed, complete a...

  12. The Effect of a Microprocessor Prosthetic Foot on Function and Quality of Life in Transtibial Amputees Who Are Limited Community Ambulators

    Science.gov (United States)

    2017-09-01

    motion and active power , will translate into improved functional performance, ambulatory safety (risk of falls) and quality of life in trans-tibial...clinical trial designed to determine if a microprocessor controlled prosthetic foot (MPF), with greater range of motion and active power , will...contact over a 6 month period of time and receive physical therapy training to minimize deviations resulting from habit or lack of training, education

  13. Should the service life of nuclear power plants be limited for technical reasons?; Mela by byt provozni zivotnost jaderne elektrarny z technickych duvodu omezena?

    Energy Technology Data Exchange (ETDEWEB)

    Schomer, E

    1995-03-01

    German nuclear power plant operating licenses take into account the fact that the design lifetime of the facilities is 40 years. The technological lifetime, however, is governed by actual ageing processes and operational burden. The service life of nuclear power plants can be extended by replacement of the steam generator and by repair or replacement of the reactor pressure vessel or parts thereof. Attention is also paid to the reactor protection systems. (J.B.). 8 figs.

  14. 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?

  15. Pocket Handbook on Reliability

    Science.gov (United States)

    1975-09-01

    exponencial distributions Weibull distribution, -xtimating reliability, confidence intervals, relia- bility growth, 0. P- curves, Bayesian analysis. 20 A S...introduction for those not familiar with reliability and a good refresher for those who are currently working in the area. LEWIS NERI, CHIEF...includes one or both of the following objectives: a) prediction of the current system reliability, b) projection on the system reliability for someI future

  16. Assessing high reliability via Bayesian approach and accelerated tests

    International Nuclear Information System (INIS)

    Erto, Pasquale; Giorgio, Massimiliano

    2002-01-01

    Sometimes the assessment of very high reliability levels is difficult for the following main reasons: - the high reliability level of each item makes it impossible to obtain, in a reasonably short time, a sufficient number of failures; - the high cost of the high reliability items to submit to life tests makes it unfeasible to collect enough data for 'classical' statistical analyses. In the above context, this paper presents a Bayesian solution to the problem of estimation of the parameters of the Weibull-inverse power law model, on the basis of a limited number (say six) of life tests, carried out at different stress levels, all higher than the normal one. The over-stressed (i.e. accelerated) tests allow the use of experimental data obtained in a reasonably short time. The Bayesian approach enables one to reduce the required number of failures adding to the failure information the available a priori engineers' knowledge. This engineers' involvement conforms to the most advanced management policy that aims at involving everyone's commitment in order to obtain total quality. A Monte Carlo study of the non-asymptotic properties of the proposed estimators and a comparison with the properties of maximum likelihood estimators closes the work

  17. Reliability in engineering '87

    International Nuclear Information System (INIS)

    Tuma, M.

    1987-01-01

    The participants heard 51 papers dealing with the reliability of engineering products. Two of the papers were incorporated in INIS, namely ''Reliability comparison of two designs of low pressure regeneration of the 1000 MW unit at the Temelin nuclear power plant'' and ''Use of probability analysis of reliability in designing nuclear power facilities.''(J.B.)

  18. Reliability analysis under epistemic uncertainty

    International Nuclear Information System (INIS)

    Nannapaneni, Saideep; Mahadevan, Sankaran

    2016-01-01

    This paper proposes a probabilistic framework to include both aleatory and epistemic uncertainty within model-based reliability estimation of engineering systems for individual limit states. Epistemic uncertainty is considered due to both data and model sources. Sparse point and/or interval data regarding the input random variables leads to uncertainty regarding their distribution types, distribution parameters, and correlations; this statistical uncertainty is included in the reliability analysis through a combination of likelihood-based representation, Bayesian hypothesis testing, and Bayesian model averaging techniques. Model errors, which include numerical solution errors and model form errors, are quantified through Gaussian process models and included in the reliability analysis. The probability integral transform is used to develop an auxiliary variable approach that facilitates a single-level representation of both aleatory and epistemic uncertainty. This strategy results in an efficient single-loop implementation of Monte Carlo simulation (MCS) and FORM/SORM techniques for reliability estimation under both aleatory and epistemic uncertainty. Two engineering examples are used to demonstrate the proposed methodology. - Highlights: • Epistemic uncertainty due to data and model included in reliability analysis. • A novel FORM-based approach proposed to include aleatory and epistemic uncertainty. • A single-loop Monte Carlo approach proposed to include both types of uncertainties. • Two engineering examples used for illustration.

  19. Reliable computer systems.

    Science.gov (United States)

    Wear, L L; Pinkert, J R

    1993-11-01

    In this article, we looked at some decisions that apply to the design of reliable computer systems. We began with a discussion of several terms such as testability, then described some systems that call for highly reliable hardware and software. The article concluded with a discussion of methods that can be used to achieve higher reliability in computer systems. Reliability and fault tolerance in computers probably will continue to grow in importance. As more and more systems are computerized, people will want assurances about the reliability of these systems, and their ability to work properly even when sub-systems fail.

  20. Human factor reliability program

    International Nuclear Information System (INIS)

    Knoblochova, L.

    2017-01-01

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

  1. Uncertainties and reliability theories for reactor safety

    International Nuclear Information System (INIS)

    Veneziano, D.

    1975-01-01

    What makes the safety problem of nuclear reactors particularly challenging is the demand for high levels of reliability and the limitation of statistical information. The latter is an unfortunate circumstance, which forces deductive theories of reliability to use models and parameter values with weak factual support. The uncertainty about probabilistic models and parameters which are inferred from limited statistical evidence can be quantified and incorporated rationally into inductive theories of reliability. In such theories, the starting point is the information actually available, as opposed to an estimated probabilistic model. But, while the necessity of introducing inductive uncertainty into reliability theories has been recognized by many authors, no satisfactory inductive theory is presently available. The paper presents: a classification of uncertainties and of reliability models for reactor safety; a general methodology to include these uncertainties into reliability analysis; a discussion about the relative advantages and the limitations of various reliability theories (specifically, of inductive and deductive, parametric and nonparametric, second-moment and full-distribution theories). For example, it is shown that second-moment theories, which were originally suggested to cope with the scarcity of data, and which have been proposed recently for the safety analysis of secondary containment vessels, are the least capable of incorporating statistical uncertainty. The focus is on reliability models for external threats (seismic accelerations and tornadoes). As an application example, the effect of statistical uncertainty on seismic risk is studied using parametric full-distribution models

  2. A new approach for reliability analysis with time-variant performance characteristics

    International Nuclear Information System (INIS)

    Wang, Zequn; Wang, Pingfeng

    2013-01-01

    Reliability represents safety level in industry practice and may variant due to time-variant operation condition and components deterioration throughout a product life-cycle. Thus, the capability to perform time-variant reliability analysis is of vital importance in practical engineering applications. This paper presents a new approach, referred to as nested extreme response surface (NERS), that can efficiently tackle time dependency issue in time-variant reliability analysis and enable to solve such problem by easily integrating with advanced time-independent tools. The key of the NERS approach is to build a nested response surface of time corresponding to the extreme value of the limit state function by employing Kriging model. To obtain the data for the Kriging model, the efficient global optimization technique is integrated with the NERS to extract the extreme time responses of the limit state function for any given system input. An adaptive response prediction and model maturation mechanism is developed based on mean square error (MSE) to concurrently improve the accuracy and computational efficiency of the proposed approach. With the nested response surface of time, the time-variant reliability analysis can be converted into the time-independent reliability analysis and existing advanced reliability analysis methods can be used. Three case studies are used to demonstrate the efficiency and accuracy of NERS approach

  3. The reliability analysis of cutting tools in the HSM processes

    OpenAIRE

    W.S. Lin

    2008-01-01

    Purpose: This article mainly describe the reliability of the cutting tools in the high speed turning by normaldistribution model.Design/methodology/approach: A series of experimental tests have been done to evaluate the reliabilityvariation of the cutting tools. From experimental results, the tool wear distribution and the tool life are determined,and the tool life distribution and the reliability function of cutting tools are derived. Further, the reliability ofcutting tools at anytime for h...

  4. A comparison of production system life cycle models

    Science.gov (United States)

    Attri, Rajesh; Grover, Sandeep

    2012-09-01

    Companies today need to keep up with the rapidly changing market conditions to stay competitive. The main issues in this paper are related to a company's market and its competitors. The prediction of market behavior is helpful for a manufacturing enterprise to build efficient production systems. However, these predictions are usually not reliable. A production system is required to adapt to changing markets, but such requirement entails higher cost. Hence, analyzing different life cycle models of the production system is necessary. In this paper, different life cycle models of the production system are compared to evaluate the distinctive features and the limitations of each model. Furthermore, the difference between product life cycle and production life cycle is summarized, and the effect of product life cycle on production life cycle is explained. Finally, a production system life cycle model, along with key activities to be performed in each stage, is proposed specifically for the manufacturing sector.

  5. System Reliability for LED-Based Products

    Energy Technology Data Exchange (ETDEWEB)

    Davis, J Lynn; Mills, Karmann; Lamvik, Michael; Yaga, Robert; Shepherd, Sarah D; Bittle, James; Baldasaro, Nick; Solano, Eric; Bobashev, Georgiy; Johnson, Cortina; Evans, Amy

    2014-04-07

    Results from accelerated life tests (ALT) on mass-produced commercially available 6” downlights are reported along with results from commercial LEDs. The luminaires capture many of the design features found in modern luminaires. In general, a systems perspective is required to understand the reliability of these devices since LED failure is rare. In contrast, components such as drivers, lenses, and reflector are more likely to impact luminaire reliability than LEDs.

  6. 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.

  7. Reliability of nuclear power plants and equipment

    International Nuclear Information System (INIS)

    1985-01-01

    The standard sets the general principles, a list of reliability indexes and demands on their selection. Reliability indexes of nuclear power plants include the simple indexes of fail-safe operation, life and maintainability, and of storage capability. All terms and notions are explained and methods of evaluating the indexes briefly listed - statistical, and calculation experimental. The dates when the standard comes in force in the individual CMEA countries are given. (M.D.)

  8. Challenges Regarding IP Core Functional Reliability

    Science.gov (United States)

    Berg, Melanie D.; LaBel, Kenneth A.

    2017-01-01

    For many years, intellectual property (IP) cores have been incorporated into field programmable gate array (FPGA) and application specific integrated circuit (ASIC) design flows. However, the usage of large complex IP cores were limited within products that required a high level of reliability. This is no longer the case. IP core insertion has become mainstream including their use in highly reliable products. Due to limited visibility and control, challenges exist when using IP cores and subsequently compromise product reliability. We discuss challenges and suggest potential solutions to critical application IP insertion.

  9. Limitaciones de esfuerzos terapéuticos: Resultados de un registro prospectivo en una sala de clínica médica Limitation of life-sustaining treatment: A prospective study developed in a clinical ward

    Directory of Open Access Journals (Sweden)

    Abel Novillo

    2008-12-01

    Full Text Available El objetivo de este trabajo fue describir el proceso de limitación de los esfuerzos terapéuticos (LET en los pacientes internados en una sala general. Para ello se realizó un estudio prospectivo descriptivo, desarrollado en la sala de internación general de un hospital universitario. Fueron evaluados pacientes que tuviesen alguna LET, asistidos por el servicio de clínica médica en un período de 60 días consecutivos. Durante el mismo se hospitalizaron 402 pacientes, 62 (15% tuvieron algún tipo de LET. Este último grupo estaba compuesto por un 66% de mujeres, la mediana de edad fue de 86 años (78-90 y de la duración de hospitalización de 12 días (8-18. La mala calidad de vida fue la causa más frecuente de LET (69%. Se brindó información acerca de las limitaciones a 43 familias (69% y 8 pacientes (13%. En la decisión participaron el médico de cabecera (50%, médicos de planta (50%, residentes (40%, la familia (42% y los propios pacientes (11%. En 7 casos hubo constancia en la historia clínica (11%. Diecisiete pacientes (27% con LET fallecieron durante la internación, mientras que 44 (71% fueron dados de alta. En conclusión, la limitación de esfuerzos terapéuticos en nuestros pacientes constituyó un hecho frecuente. No se logró identificar un proceso uniforme o sistematizado para la toma de la decisión de LET. Resulta innegable la necesidad de normativas que guíen al equipo de salud en la toma de decisiones, tranquilicen a familiares y acompañen a los pacientes en sus reales necesidades.The purpose of this study is to describe the limiting life-sustaining treatment process of patients admitted to a general ward. A prospective descriptive study was designed. The setting was the general ward of universitary hospital. Study participants were patients assisted by the internal medicine department during a 60- consecutive days period who had limitations of life sustaining treatments. During the study period, 402 patients were

  10. Solid State Lighting Reliability Components to Systems

    CERN Document Server

    Fan, XJ

    2013-01-01

    Solid State Lighting Reliability: Components to Systems begins with an explanation of the major benefits of solid state lighting (SSL) when compared to conventional lighting systems including but not limited to long useful lifetimes of 50,000 (or more) hours and high efficacy. When designing effective devices that take advantage of SSL capabilities the reliability of internal components (optics, drive electronics, controls, thermal design) take on critical importance. As such a detailed discussion of reliability from performance at the device level to sub components is included as well as the integrated systems of SSL modules, lamps and luminaires including various failure modes, reliability testing and reliability performance. This book also: Covers the essential reliability theories and practices for current and future development of Solid State Lighting components and systems Provides a systematic overview for not only the state-of-the-art, but also future roadmap and perspectives of Solid State Lighting r...

  11. Accelerated reliability demonstration under competing failure modes

    International Nuclear Information System (INIS)

    Luo, Wei; Zhang, Chun-hua; Chen, Xun; Tan, Yuan-yuan

    2015-01-01

    The conventional reliability demonstration tests are difficult to apply to products with competing failure modes due to the complexity of the lifetime models. This paper develops a testing methodology based on the reliability target allocation for reliability demonstration under competing failure modes at accelerated conditions. The specified reliability at mission time and the risk caused by sampling of the reliability target for products are allocated for each failure mode. The risk caused by degradation measurement fitting of the target for a product involving performance degradation is equally allocated to each degradation failure mode. According to the allocated targets, the accelerated life reliability demonstration test (ALRDT) plans for the failure modes are designed. The accelerated degradation reliability demonstration test plans and the associated ALRDT plans for the degradation failure modes are also designed. Next, the test plan and the decision rules for the products are designed. Additionally, the effects of the discreteness of sample size and accepted number of failures for failure modes on the actual risks caused by sampling for the products are investigated. - Highlights: • Accelerated reliability demonstration under competing failure modes is studied. • The method is based on the reliability target allocation involving the risks. • The test plan for the products is based on the plans for all the failure modes. • Both failure mode and degradation failure modes are considered. • The error of actual risks caused by sampling for the products is small enough

  12. Reliability of thermal interface materials: A review

    International Nuclear Information System (INIS)

    Due, Jens; Robinson, Anthony J.

    2013-01-01

    Thermal interface materials (TIMs) are used extensively to improve thermal conduction across two mating parts. They are particularly crucial in electronics thermal management since excessive junction-to-ambient thermal resistances can cause elevated temperatures which can negatively influence device performance and reliability. Of particular interest to electronic package designers is the thermal resistance of the TIM layer at the end of its design life. Estimations of this allow the package to be designed to perform adequately over its entire useful life. To this end, TIM reliability studies have been performed using accelerated stress tests. This paper reviews the body of work which has been performed on TIM reliability. It focuses on the various test methodologies with commentary on the results which have been obtained for the different TIM materials. Based on the information available in the open literature, a test procedure is proposed for TIM selection based on beginning and end of life performance. - Highlights: ► This paper reviews the body of work which has been performed on TIM reliability. ► Test methodologies for reliability testing are outlined. ► Reliability results for the different TIM materials are discussed. ► A test procedure is proposed for TIM selection BOLife and EOLife performance.

  13. Reliability analysis of pipelines under H2S environment as a part of ageing management

    International Nuclear Information System (INIS)

    Santosh; Vinod, Gopika; Saraf, R.K.; Ghosh, A.K.; Kushwaha, H.S.

    2006-01-01

    Ageing management programme in a plant calls for the estimation of remaining life of the component. Reliability analysis methods using remaining life estimation models have found profound application in providing directives in ageing management programme. As a part of ageing management programme of H 2 S based heavy water plants, the remaining life estimation models are applied to the pipelines carrying H 2 S. The pipelines under H 2 S environment are more susceptible to the internal corrosion thereby reducing the pipeline's load carrying capacity. The objective of this study is to obtain the remaining life of pipelines under ageing due to internal corrosion. The ageing assessment of pipelines involves estimating the failure pressure of a pipeline and evaluating the failure surface equation. Several failure pressure models developed for assessing the pipeline's remaining strength due to internal corrosion were studied for this purpose. From the study, it was found that the modified B31G failure pressure model is most suitable for modeling the pipeline failure pressure. Due to the presence of non-linearity in the failure surface equation or limit state function and non-normal variables, the first order second moment method has been employed for carrying out the reliability analysis. The uncertainties of the random variables on which the limit state function depends are modeled using the probability distributions. The failure probabilities of the pipelines have been evaluated for the service lives of 15 and 25 years, which are the present life and designed life respectively. In addition, sensitivity analysis was carried out to identify the most important sensitive parameters in reliability analysis estimation. The paper highlights the application of these methodologies in the context of pipeline remaining life estimation with a suitable case study. (author)

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

    DEFF Research Database (Denmark)

    Wang, Huai; Zhou, Dao; Blaabjerg, Frede

    2013-01-01

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

  15. Human reliability analysis

    International Nuclear Information System (INIS)

    Dougherty, E.M.; Fragola, J.R.

    1988-01-01

    The authors present a treatment of human reliability analysis incorporating an introduction to probabilistic risk assessment for nuclear power generating stations. They treat the subject according to the framework established for general systems theory. Draws upon reliability analysis, psychology, human factors engineering, and statistics, integrating elements of these fields within a systems framework. Provides a history of human reliability analysis, and includes examples of the application of the systems approach

  16. Reliability of electronic systems

    International Nuclear Information System (INIS)

    Roca, Jose L.

    2001-01-01

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

  17. Operational safety reliability research

    International Nuclear Information System (INIS)

    Hall, R.E.; Boccio, J.L.

    1986-01-01

    Operating reactor events such as the TMI accident and the Salem automatic-trip failures raised the concern that during a plant's operating lifetime the reliability of systems could degrade from the design level that was considered in the licensing process. To address this concern, NRC is sponsoring the Operational Safety Reliability Research project. The objectives of this project are to identify the essential tasks of a reliability program and to evaluate the effectiveness and attributes of such a reliability program applicable to maintaining an acceptable level of safety during the operating lifetime at the plant

  18. 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.

  19. Shelf-life Assessment of Food Undergoing Oxidation-A Review.

    Science.gov (United States)

    Calligaris, Sonia; Manzocco, Lara; Anese, Monica; Nicoli, Maria Cristina

    2016-08-17

    Oxidation is the most common event leading to the end of shelf life of microbiologically stable foods. Thus, a reliable shelf-life assessment is crucial to verify how long the product will last before it becomes oxidized to an unacceptable level to the consumers. Shelf-life assessment strategies of foods and beverages suffering oxidation are critically discussed focusing on definition of the acceptability limit, as well as the choice of the proper oxidative indicators, and methodologies for shelf-life testing. Testing methodologies for shelf-life determination under actual and accelerated storage conditions are considered, highlighting possible uncertainties, pitfalls, and future research needs.

  20. Imaging a memory trace over half a life-time in the medial temporal lobe reveals a time-limited role of CA3 neurons in retrieval

    Science.gov (United States)

    Lux, Vanessa; Atucha, Erika; Kitsukawa, Takashi; Sauvage, Magdalena M

    2016-01-01

    Whether retrieval still depends on the hippocampus as memories age or relies then on cortical areas remains a major controversy. Despite evidence for a functional segregation between CA1, CA3 and parahippocampal areas, their specific role within this frame is unclear. Especially, the contribution of CA3 is questionable as very remote memories might be too degraded to be used for pattern completion. To identify the specific role of these areas, we imaged brain activity in mice during retrieval of recent, early remote and very remote fear memories by detecting the immediate-early gene Arc. Investigating correlates of the memory trace over an extended period allowed us to report that, in contrast to CA1, CA3 is no longer recruited in very remote retrieval. Conversely, we showed that parahippocampal areas are then maximally engaged. These results suggest a shift from a greater contribution of the trisynaptic loop to the temporoammonic pathway for retrieval. DOI: http://dx.doi.org/10.7554/eLife.11862.001 PMID:26880561

  1. Weibull distribution in reliability data analysis in nuclear power plant

    International Nuclear Information System (INIS)

    Ma Yingfei; Zhang Zhijian; Zhang Min; Zheng Gangyang

    2015-01-01

    Reliability is an important issue affecting each stage of the life cycle ranging from birth to death of a product or a system. The reliability engineering includes the equipment failure data processing, quantitative assessment of system reliability and maintenance, etc. Reliability data refers to the variety of data that describe the reliability of system or component during its operation. These data may be in the form of numbers, graphics, symbols, texts and curves. Quantitative reliability assessment is the task of the reliability data analysis. It provides the information related to preventing, detect, and correct the defects of the reliability design. Reliability data analysis under proceed with the various stages of product life cycle and reliability activities. Reliability data of Systems Structures and Components (SSCs) in Nuclear Power Plants is the key factor of probabilistic safety assessment (PSA); reliability centered maintenance and life cycle management. The Weibull distribution is widely used in reliability engineering, failure analysis, industrial engineering to represent manufacturing and delivery times. It is commonly used to model time to fail, time to repair and material strength. In this paper, an improved Weibull distribution is introduced to analyze the reliability data of the SSCs in Nuclear Power Plants. An example is given in the paper to present the result of the new method. The Weibull distribution of mechanical equipment for reliability data fitting ability is very strong in nuclear power plant. It's a widely used mathematical model for reliability analysis. The current commonly used methods are two-parameter and three-parameter Weibull distribution. Through comparison and analysis, the three-parameter Weibull distribution fits the data better. It can reflect the reliability characteristics of the equipment and it is more realistic to the actual situation. (author)

  2. A study of the reliability, validity and responsiveness of the HIV overview of problems evaluation system (HOPES) in assessing the quality of life of patients with AIDS and symptomatic HIV infection

    NARCIS (Netherlands)

    de Boer, J. B.; Sprangers, M. A.; Aaronson, N. K.; Lange, J. M.; van Dam, F. S.

    1996-01-01

    The objective of this study was to evaluate the feasibility, reliability, validity and responsiveness of the HIV Overview of Problems Evaluation System (HOPES) in a Dutch sample. The HOPES was administered three times in a one-year period to a sample of 106 outpatients with a symptomatic

  3. Exact reliability quantification of highly reliable systems with maintenance

    Energy Technology Data Exchange (ETDEWEB)

    Bris, Radim, E-mail: radim.bris@vsb.c [VSB-Technical University Ostrava, Faculty of Electrical Engineering and Computer Science, Department of Applied Mathematics, 17. listopadu 15, 70833 Ostrava-Poruba (Czech Republic)

    2010-12-15

    When a system is composed of highly reliable elements, exact reliability quantification may be problematic, because computer accuracy is limited. Inaccuracy can be due to different aspects. For example, an error may be made when subtracting two numbers that are very close to each other, or at the process of summation of many very different numbers, etc. The basic objective of this paper is to find a procedure, which eliminates errors made by PC when calculations close to an error limit are executed. Highly reliable system is represented by the use of directed acyclic graph which is composed from terminal nodes, i.e. highly reliable input elements, internal nodes representing subsystems and edges that bind all of these nodes. Three admissible unavailability models of terminal nodes are introduced, including both corrective and preventive maintenance. The algorithm for exact unavailability calculation of terminal nodes is based on merits of a high-performance language for technical computing MATLAB. System unavailability quantification procedure applied to a graph structure, which considers both independent and dependent (i.e. repeatedly occurring) terminal nodes is based on combinatorial principle. This principle requires summation of a lot of very different non-negative numbers, which may be a source of an inaccuracy. That is why another algorithm for exact summation of such numbers is designed in the paper. The summation procedure uses benefits from a special number system with the base represented by the value 2{sup 32}. Computational efficiency of the new computing methodology is compared with advanced simulation software. Various calculations on systems from references are performed to emphasize merits of the methodology.

  4. Significant human beta-cell turnover is limited to the first three decades of life as determined by in vivo thymidine analog incorporation and radiocarbon dating.

    Science.gov (United States)

    Perl, S; Kushner, J A; Buchholz, B A; Meeker, A K; Stein, G M; Hsieh, M; Kirby, M; Pechhold, S; Liu, E H; Harlan, D M; Tisdale, J F

    2010-10-01

    Diabetes mellitus results from an absolute or relative deficiency of insulin-producing pancreatic β-cells. The turnover rate of adult human β-cells remains unknown. We employed two techniques to examine adult human islet β-cell turnover and longevity in vivo. Subjects enrolled in National Institutes of Health clinical trials received thymidine analogs [iododeoxyuridine (IdU) or bromodeoxyuridine (BrdU)] 8 d to 4 yr prior to death. Archival autopsy samples from 10 patients (aged 17-74 yr) were employed to assess β-cell turnover by scoring nuclear analog labeling within insulin-staining cells. Human adult β-cell longevity was determined by estimating the cells' genomic DNA integration of atmospheric (14)C. DNA was purified from pancreatic islets isolated from cadaveric donors; whole islet prep DNA was obtained from a 15-yr-old donor, and purified β-cell DNA was obtained from two donors (ages 48 and 80 yr). (14)C levels were then determined using accelerator mass spectrometry. Cellular "birth date" was determined by comparing the subject's DNA (14)C content relative to a well-established (14)C atmospheric prevalence curve. In the two subjects less than 20 yr of age, 1-2% of the β-cell nuclei costained for BrdU/IdU. No β-cell nuclei costained in the eight patients more than 30 yr old. Consistent with the BrdU/IdU turnover data, β-cell DNA (14)C content indicated that the "birth date" of cells occurred within the subject's first 30 yr of life. Under typical circumstances, human β-cells and their cellular precursors are established by young adulthood.

  5. 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.

  6. 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.

  7. 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

  8. 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...

  9. Reliability of neural encoding

    DEFF Research Database (Denmark)

    Alstrøm, Preben; Beierholm, Ulrik; Nielsen, Carsten Dahl

    2002-01-01

    The reliability with which a neuron is able to create the same firing pattern when presented with the same stimulus is of critical importance to the understanding of neuronal information processing. We show that reliability is closely related to the process of phaselocking. Experimental results f...

  10. Reliability engineering for nuclear and other high technology systems

    International Nuclear Information System (INIS)

    Lakner, A.A.; Anderson, R.T.

    1985-01-01

    This book is written for the reliability instructor, program manager, system engineer, design engineer, reliability engineer, nuclear regulator, probability risk assessment (PRA) analyst, general manager and others who are involved in system hardware acquisition, design and operation and are concerned with plant safety and operational cost-effectiveness. It provides criteria, guidelines and comprehensive engineering data affecting reliability; it covers the key aspects of system reliability as it relates to conceptual planning, cost tradeoff decisions, specification, contractor selection, design, test and plant acceptance and operation. It treats reliability as an integrated methodology, explicitly describing life cycle management techniques as well as the basic elements of a total hardware development program, including: reliability parameters and design improvement attributes, reliability testing, reliability engineering and control. It describes how these elements can be defined during procurement, and implemented during design and development to yield reliable equipment. (author)

  11. Bayesian methods in reliability

    Science.gov (United States)

    Sander, P.; Badoux, R.

    1991-11-01

    The present proceedings from a course on Bayesian methods in reliability encompasses Bayesian statistical methods and their computational implementation, models for analyzing censored data from nonrepairable systems, the traits of repairable systems and growth models, the use of expert judgment, and a review of the problem of forecasting software reliability. Specific issues addressed include the use of Bayesian methods to estimate the leak rate of a gas pipeline, approximate analyses under great prior uncertainty, reliability estimation techniques, and a nonhomogeneous Poisson process. Also addressed are the calibration sets and seed variables of expert judgment systems for risk assessment, experimental illustrations of the use of expert judgment for reliability testing, and analyses of the predictive quality of software-reliability growth models such as the Weibull order statistics.

  12. Qualidade de vida de crianças e adolescentes de São Paulo: confiabilidade e validade da versão brasileira do questionário genérico Pediatric Quality of Life InventoryTM versão 4.0 Quality of life of children and adolescents from São Paulo: reliability and validity of the Brazilian version of the Pediatric Quality of Life InventoryTM version 4.0 Generic Core Scales

    Directory of Open Access Journals (Sweden)

    Denise A. Klatchoian

    2008-08-01

    Full Text Available OBJETIVOS: Avaliar a confiabilidade e a validade da versão brasileira do questionário genérico Pediatric Quality of Life InventoryTM (PedsQL TM 4.0 e mensurar a qualidade de vida de crianças e adolescentes saudáveis e de pacientes com doenças reumáticas. MÉTODOS: No processo de validação, seguimos a metodologia proposta pelos idealizadores da versão original em inglês do questionário PedsQL TM 4.0. O instrumento foi administrado por entrevista em dois grupos: 240 crianças e adolescentes aparentemente saudáveis de São Paulo (SP e 105 pacientes com doenças reumáticas crônicas, pareados por idade, e aos respectivos pais ou responsáveis. O questionário foi aplicado nos cuidadores e nas crianças separadamente e no mesmo dia. RESULTADOS: Os valores do teste alfa de Cronbach situaram-se entre 0,6 e 0,9 para todas as dimensões, demonstrando uma consistência interna adequada. Os pacientes com doenças reumáticas apresentaram uma redução significativa na qualidade de vida quando comparados com as crianças saudáveis (p OBJECTIVES: To evaluate the reliability and validity of the Brazilian version of the Pediatric Quality of Life InventoryTM (PedsQL TM 4.0 Generic Core Scales and measure the quality of life of healthy children and adolescents and patients with rheumatic diseases. METHODS: We followed the translation methodology proposed by the developer of the original English version of the PedsQL TM 4.0. The instrument was administered by interviews in two groups: 240 apparently healthy children and adolescents from São Paulo (SP, Brazil and 105 patients with chronic rheumatic diseases, matched by age, as well as to their respective parents or caregivers. The parent proxy-report was administered to the children's parents or caregivers separately on the same day. RESULTS: Cronbach's alpha values were between 0.6 and 0.9 for all dimensions, demonstrating adequate internal consistency. Patients with rheumatic diseases reported

  13. TFTR CAMAC power supplies reliability

    International Nuclear Information System (INIS)

    Camp, R.A.; Bergin, W.

    1989-01-01

    Since the expected life of the Tokamak Fusion Test Reactor (TFTR) has been extended into the early 1990's, the issues of equipment wear-out, when to refurbish/replace, and the costs associated with these decisions, must be faced. The management of the maintenance of the TFTR Central Instrumentation, Control and Data Acquisition System (CICADA) power supplies within the CAMAC network is a case study of a set of systems to monitor repairable systems reliability, costs, and results of action. The CAMAC network is composed of approximately 500 racks, each with its own power supply. By using a simple reliability estimator on a coarse time interval, in conjunction with determining the root cause of individual failures, a cost effective repair and maintenance program has been realized. This paper describes the estimator, some of the specific causes for recurring failures and their correction, and the subsequent effects on the reliability estimator. By extension of this program the authors can assess the continued viability of CAMAC power supplies into the future, predicting wear-out and developing cost effective refurbishment/replacement policies. 4 refs., 3 figs., 1 tab

  14. Equipment Reliability Process in Krsko NPP

    International Nuclear Information System (INIS)

    Gluhak, M.

    2016-01-01

    To ensure long-term safe and reliable plant operation, equipment operability and availability must also be ensured by setting a group of processes to be established within the nuclear power plant. Equipment reliability process represents the integration and coordination of important equipment reliability activities into one process, which enables equipment performance and condition monitoring, preventive maintenance activities development, implementation and optimization, continuous improvement of the processes and long term planning. The initiative for introducing systematic approach for equipment reliability assuring came from US nuclear industry guided by INPO (Institute of Nuclear Power Operations) and by participation of several US nuclear utilities. As a result of the initiative, first edition of INPO document AP-913, 'Equipment Reliability Process Description' was issued and it became a basic document for implementation of equipment reliability process for the whole nuclear industry. The scope of equipment reliability process in Krsko NPP consists of following programs: equipment criticality classification, preventive maintenance program, corrective action program, system health reports and long-term investment plan. By implementation, supervision and continuous improvement of those programs, guided by more than thirty years of operating experience, Krsko NPP will continue to be on a track of safe and reliable operation until the end of prolonged life time. (author).

  15. Reliability assessments in qualitative health promotion research.

    Science.gov (United States)

    Cook, Kay E

    2012-03-01

    This article contributes to the debate about the use of reliability assessments in qualitative research in general, and health promotion research in particular. In this article, I examine the use of reliability assessments in qualitative health promotion research in response to health promotion researchers' commonly held misconception that reliability assessments improve the rigor of qualitative research. All qualitative articles published in the journal Health Promotion International from 2003 to 2009 employing reliability assessments were examined. In total, 31.3% (20/64) articles employed some form of reliability assessment. The use of reliability assessments increased over the study period, ranging from qualitative articles decreased. The articles were then classified into four types of reliability assessments, including the verification of thematic codes, the use of inter-rater reliability statistics, congruence in team coding and congruence in coding across sites. The merits of each type were discussed, with the subsequent discussion focusing on the deductive nature of reliable thematic coding, the limited depth of immediately verifiable data and the usefulness of such studies to health promotion and the advancement of the qualitative paradigm.

  16. Energy Efficient Authentication and Authorization for Multinode Cooperative Connectivity and Reliability

    DEFF Research Database (Denmark)

    Rohokale, Vandana M.

    2013-01-01

    their effective QoS via cooperation. The performance of wireless networks is greatly affected by some of the channel parameters such as bandwidth and power scarcity, multi-user interference, non-reliability due to signal fading, vulnerability to the attacks, etc. The cooperative diversity mechanism makes use...... of the benefits of wireless sensor network scalability in terms of cooperative resource sharing wherein multiple diversity channels are created that results into the higher transmission rates, increased throughput and coverage range, improvement in reliability and end-to-end performance and much more. Cooperative......Wireless communication is a great revolution but it still suffers from limited battery life, broken connections from multi-path fading and insufficient coverage. Simple cooperation can mak a big difference in coverage range, energy and battery life. In CWC, the active nodes may increase...

  17. Design for Reliability of Power Electronics for Grid-Connected Photovoltaic Systems

    DEFF Research Database (Denmark)

    Yang, Yongheng; Sangwongwanich, Ariya; Blaabjerg, Frede

    2016-01-01

    Power electronics is the enabling technology for optimizing energy harvesting from renewable systems like Photovoltaic (PV) and wind power systems, and also for interfacing grid-friendly energy systems. Advancements in the power semiconductor technology (e.g., wide band-gap devices) have pushed...... the conversion efficiency of power electronics to above 98%, where however te reliability of power electronics is becoming of high concern. Therefore, it is important to design for reliable power electronic systems to lower the risks of many failures during operation; otherwise will increase the cost...... for maintenance and reputation, thus affecting the cost of PV energy. Today's PV power conversion applications require the power electronic systems with low failure rates during a service life of 20 years or even more. To achieve so, it is vital to know the main life-limiting factors of power electronic systems...

  18. Reliability of construction materials

    International Nuclear Information System (INIS)

    Merz, H.

    1976-01-01

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

  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...... of the uncertainties and their interplay is the developed, step-by-step. The concepts presented are illustrated by numerous examples throughout the text....

  20. Reliability and mechanical design

    International Nuclear Information System (INIS)

    Lemaire, Maurice

    1997-01-01

    A lot of results in mechanical design are obtained from a modelisation of physical reality and from a numerical solution which would lead to the evaluation of needs and resources. The goal of the reliability analysis is to evaluate the confidence which it is possible to grant to the chosen design through the calculation of a probability of failure linked to the retained scenario. Two types of analysis are proposed: the sensitivity analysis and the reliability analysis. Approximate methods are applicable to problems related to reliability, availability, maintainability and safety (RAMS)