WorldWideScience

Sample records for reliability maintainability supportability

  1. Cost-effectiveness of combustion turbines: recommendations for reliability, maintainability, supportability and maintenance requirements

    Energy Technology Data Exchange (ETDEWEB)

    Meuwisse, C.; Despujols, A. [Electricite de France, Research and Development Division, Chatou (France); Givaudan, B. [Electricite de France, Research and Development Division - SEPTEN, Villeurbanne (France); Lafage, L. [Electricite de France, Engineering and Construction Division - CNET, Paris (France)

    1998-12-31

    The profitability of combustion turbines intended for export is of extreme importance for Electricite de France. It is principally during the development phase of a project that one can ensure resect of two indissociable factors, essential to the per-kWh production cost: global operating costs and performance in terms of reliability and availability. The approach proposed here advocates the global acquisition of the installation and its logistic support. Generally applicable recommendations are given. They enable integrating in the future plant specifications all requirements relative to plant reliability, availability, maintainability and logistic support. They are structured according to type: expression of needs and management factors. (orig.) 4 refs.

  2. Cost-effectiveness of combustion turbines: recommendations for reliability, maintainability, supportability and maintenance requirements

    Energy Technology Data Exchange (ETDEWEB)

    Meuwisse, C; Despujols, A [Electricite de France, Research and Development Division, Chatou (France); Givaudan, B [Electricite de France, Research and Development Division - SEPTEN, Villeurbanne (France); Lafage, L [Electricite de France, Engineering and Construction Division - CNET, Paris (France)

    1999-12-31

    The profitability of combustion turbines intended for export is of extreme importance for Electricite de France. It is principally during the development phase of a project that one can ensure resect of two indissociable factors, essential to the per-kWh production cost: global operating costs and performance in terms of reliability and availability. The approach proposed here advocates the global acquisition of the installation and its logistic support. Generally applicable recommendations are given. They enable integrating in the future plant specifications all requirements relative to plant reliability, availability, maintainability and logistic support. They are structured according to type: expression of needs and management factors. (orig.) 4 refs.

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

    Science.gov (United States)

    Ebeling, Charles E.

    1996-01-01

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

  4. Reliability and maintainability

    International Nuclear Information System (INIS)

    1994-01-01

    Several communications in this conference are concerned with nuclear plant reliability and maintainability; their titles are: maintenance optimization of stand-by Diesels of 900 MW nuclear power plants; CLAIRE: an event-based simulation tool for software testing; reliability as one important issue within the periodic safety review of nuclear power plants; design of nuclear building ventilation by the means of functional analysis; operation characteristic analysis for a power industry plant park, as a function of influence parameters

  5. AECL's reliability and maintainability program

    International Nuclear Information System (INIS)

    Wolfe, W.A.; Nieuwhof, G.W.E.

    1976-05-01

    AECL's reliability and maintainability program for nuclear generating stations is described. How the various resources of the company are organized to design and construct stations that operate reliably and safely is shown. Reliability and maintainability includes not only special mathematically oriented techniques, but also the technical skills and organizational abilities of the company. (author)

  6. 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.

  7. Evolving Reliability and Maintainability Allocations for NASA Ground Systems

    Science.gov (United States)

    Munoz, Gisela; Toon, T.; Toon, J.; Conner, A.; Adams, T.; Miranda, D.

    2016-01-01

    This paper describes the methodology and value of modifying allocations to reliability and maintainability requirements for the NASA Ground Systems Development and Operations (GSDO) programs subsystems. As systems progressed through their design life cycle and hardware data became available, it became necessary to reexamine the previously derived allocations. This iterative process provided an opportunity for the reliability engineering team to reevaluate allocations as systems moved beyond their conceptual and preliminary design phases. These new allocations are based on updated designs and maintainability characteristics of the components. It was found that trade-offs in reliability and maintainability were essential to ensuring the integrity of the reliability and maintainability analysis. This paper discusses the results of reliability and maintainability reallocations made for the GSDO subsystems as the program nears the end of its design phase.

  8. Reliability and maintainability data acquisition in equipment development tests

    International Nuclear Information System (INIS)

    Haire, M.J.; Gift, E.H.

    1983-10-01

    The need for collection of reliability, maintainability, and availability data adds a new dimension to the data acquisition requirements of equipment development tests. This report describes the reliability and maintainability data that are considered necessary to ensure that sufficient and high quality data exist for a comprehensive, quantitative evaluation of equipment and system availability. These necessary data are presented as a set of data collection forms. Three data acquisition forms are discussed: an inventory and technical data form, which is filed by the design engineer when the design is finished or the equipment is received; an event report form, which is completed by the senior test operator at each shutdown; and a maintainability report, which is a collaborative effort between senior operators and lead engineers and is completed on restart. In addition, elements of a reliability, maintainability evaluation program are described. Emphasis is placed on the role of data, its storage, and use in such a program

  9. Cost-effective solutions to maintaining smart grid reliability

    Science.gov (United States)

    Qin, Qiu

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

  10. Improved reliability, maintainability and safety through elastomer upgrading

    International Nuclear Information System (INIS)

    Wensel, R.; Wittich, K.C.

    1995-01-01

    Equipment in nuclear plants has historically contained whatever elastomer each component supplier traditionally used for corresponding non-nuclear service. The resulting proliferation of elastomer compounds, many of which are far from optimal for the service conditions (e.g., pressure, temperature, radiation, etc.), has multiplied the costs to provide station reliability, maintainability and safety. Cost-effective improvements are being achieved in CANDU plants by upgrading and standardizing on a handful of high performing elastomer compounds. These upgraded materials offer significant gains in service life over the materials they replace (often by factors of 2 or more). This rationalization of elastomer compounds also facilitates the EQ process for safety-related equipment. Detailed test data on aging is currently being generated for these specific elastomers, encompassing the conditions and media (air, water, oil) common in CANDU service. Two key elements characterize this testing. First, each result is specific to the compound used in the test, and second, it is specific to the tested failure mode (e.g., compression set, extrusion, fracture, etc.). Having fewer, but more thoroughly tested compounds, avoids the penalty (associated with poorly characterized materials) of having to replace parts prematurely because of conservatism, while maintaining safe, reliable service. This paper provides an overview of this approach covering: the benefits of compound rationalization; and the how and why of establishing relevant failure criteria; appropriate quality assurance to maintain EQ; procurement, storage and handling guidelines; and monitoring and predicting in-service degradation. (author)

  11. Reliability And Maintainability Issues for the Next Linear Collider

    International Nuclear Information System (INIS)

    Wilson, Zane J.; Gold, Saul L.; Koontz, Ron F.; Lavine, Ted L.

    2011-01-01

    Large accelerators for high energy physics research traditionally have been designed using informal best design, engineering, and management practices to achieve acceptable levels of operational availability. However, the Next Linear Collider(NLC) project presents a particular challenge for operational availability due to the unprecedented size and complexity of the accelerator systems required to achieve the physics goals of high center-of-mass energy and high luminosity. Formal reliability and maintainability analysis, design, and implementation will be required to achieve acceptable operational availability for the high energy physics research program. This paper introduces some of the basic concepts of reliability analysis and applies them to the 2.6-cm microwave power system of the two 10-km-long, 250-GeV linacs that are currently proposed for the NLC design.

  12. Some areas of reliability technique which have been neglected to some extent - maintainability - human reliability - mechanical reliability - repairable systems

    International Nuclear Information System (INIS)

    Akersten, P.A.

    1985-01-01

    The present thesis consists of four papers, three of which are of a expositary nature and one more theoretical. The first two papers have a natural coupling to the man-machine interface. The first paper is devoted to the concept of maintainability and the role of man as maintenance technician. The second paper discusses aspects of human reliability, mainly studying man as operator. However, maintenance tasks can be studied in the same manner. The third paper concerns reliability prediction for mechanical components. This is an area of vital importance for the reliability practitioner, who needs realistic and easy-to-use mathematical models for different failure modes. The fourth paper discusses mathematical models for repairable systems, especially the problem of testing whether a constant event intensity model is adequate or not. (author)

  13. 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.

  14. Training and Maintaining System-Wide Reliability in Outcome Management.

    Science.gov (United States)

    Barwick, Melanie A; Urajnik, Diana J; Moore, Julia E

    2014-01-01

    The Child and Adolescent Functional Assessment Scale (CAFAS) is widely used for outcome management, for providing real time client and program level data, and the monitoring of evidence-based practices. Methods of reliability training and the assessment of rater drift are critical for service decision-making within organizations and systems of care. We assessed two approaches for CAFAS training: external technical assistance and internal technical assistance. To this end, we sampled 315 practitioners trained by external technical assistance approach from 2,344 Ontario practitioners who had achieved reliability on the CAFAS. To assess the internal technical assistance approach as a reliable alternative training method, 140 practitioners trained internally were selected from the same pool of certified raters. Reliabilities were high for both practitioners trained by external technical assistance and internal technical assistance approaches (.909-.995, .915-.997, respectively). 1 and 3-year estimates showed some drift on several scales. High and consistent reliabilities over time and training method has implications for CAFAS training of behavioral health care practitioners, and the maintenance of CAFAS as a global outcome management tool in systems of care.

  15. Direct unavailability computation of a maintained highly reliable system

    Czech Academy of Sciences Publication Activity Database

    Briš, R.; Byczanski, Petr

    2010-01-01

    Roč. 224, č. 3 (2010), s. 159-170 ISSN 1748-0078 Grant - others:GA Mšk(CZ) MSM6198910007 Institutional research plan: CEZ:AV0Z30860518 Keywords : high reliability * availability * directed acyclic graph Subject RIV: BA - General Mathematics http:// journals .pepublishing.com/content/rtp3178l17923m46/

  16. Forward Capacity Markets: Maintaining Grid Reliability in Europe

    OpenAIRE

    Chaigneau, Matthieu

    2012-01-01

    The liberalization process of the electricity industry in many countries leads to new rules and new challenges for the grid management. System reliability is a major concern, mainly because of (a) the high level penetration of renewable energy sources and (b) the growing peak load and environmental regulations In most electricity markets, peak resources operate only during a short period, and at a high operating cost, jeopardizing their return on investment, while low-cost base resources make...

  17. Reliability and Maintainability Engineering - A Major Driver for Safety and Affordability

    Science.gov (United States)

    Safie, Fayssal M.

    2011-01-01

    The United States National Aeronautics and Space Administration (NASA) is in the midst of an effort to design and build a safe and affordable heavy lift vehicle to go to the moon and beyond. To achieve that, NASA is seeking more innovative and efficient approaches to reduce cost while maintaining an acceptable level of safety and mission success. One area that has the potential to contribute significantly to achieving NASA safety and affordability goals is Reliability and Maintainability (R&M) engineering. Inadequate reliability or failure of critical safety items may directly jeopardize the safety of the user(s) and result in a loss of life. Inadequate reliability of equipment may directly jeopardize mission success. Systems designed to be more reliable (fewer failures) and maintainable (fewer resources needed) can lower the total life cycle cost. The Department of Defense (DOD) and industry experience has shown that optimized and adequate levels of R&M are critical for achieving a high level of safety and mission success, and low sustainment cost. Also, lessons learned from the Space Shuttle program clearly demonstrated the importance of R&M engineering in designing and operating safe and affordable launch systems. The Challenger and Columbia accidents are examples of the severe impact of design unreliability and process induced failures on system safety and mission success. These accidents demonstrated the criticality of reliability engineering in understanding component failure mechanisms and integrated system failures across the system elements interfaces. Experience from the shuttle program also shows that insufficient Reliability, Maintainability, and Supportability (RMS) engineering analyses upfront in the design phase can significantly increase the sustainment cost and, thereby, the total life cycle cost. Emphasis on RMS during the design phase is critical for identifying the design features and characteristics needed for time efficient processing

  18. 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

  19. Nuclear power generating station operability assurance reliability, availability, and maintainability application for maintenance management

    International Nuclear Information System (INIS)

    Cleveland, J.W.; Regenie, T.R.; Wilson, R.J.

    1985-01-01

    Environmental qualification and equipment warrantee insurance stipulations should be supplemented with a reliable maintainability program structured to identify and control fast failing subcomponents within critical equipment. Anticipation of equipment subcomponent failures can control unnecessary plant off-line occurrences. Incorporation of reliability, availability, and maintainability considerations into plant maintenance policies on power generation and safety related items have positive cost benefit advantages

  20. Teach, learn, and motivate: tools to reliability, availability, and maintainability

    International Nuclear Information System (INIS)

    Allison, D.

    1986-01-01

    The recent introduction of performance-based training by the Institute for Nuclear Power Operations (INPO) should not be a surprise to the nuclear industry. The recommended performance-based training method by INPO in one form or another addresses the techniques of teaching and sets the atmosphere for employee learning and motivation. The purpose of this paper is to explore the underlying concepts of why performance-based training yields such high results. The main emphasis will be on the general topics of teaching, learning, and student motivation as each applies to hands-on training. To support each of these topics, ancient philosophers' theories are presented. the intent is to show that hands-on performance-based training applies to engineers and other professional disciplines as well as technicians and operators

  1. Reliability and maintainability assessment factors for reliable fault-tolerant systems

    Science.gov (United States)

    Bavuso, S. J.

    1984-01-01

    A long term goal of the NASA Langley Research Center is the development of a reliability assessment methodology of sufficient power to enable the credible comparison of the stochastic attributes of one ultrareliable system design against others. This methodology, developed over a 10 year period, is a combined analytic and simulative technique. An analytic component is the Computer Aided Reliability Estimation capability, third generation, or simply CARE III. A simulative component is the Gate Logic Software Simulator capability, or GLOSS. The numerous factors that potentially have a degrading effect on system reliability and the ways in which these factors that are peculiar to highly reliable fault tolerant systems are accounted for in credible reliability assessments. Also presented are the modeling difficulties that result from their inclusion and the ways in which CARE III and GLOSS mitigate the intractability of the heretofore unworkable mathematics.

  2. The Centralized Reliability Data Organization (CREDO); an advanced nuclear reactor reliability, availability, and maintainability data bank and data analysis center

    International Nuclear Information System (INIS)

    Knee, H.E.

    1991-01-01

    The Centralized Reliability Data Organization (CREDO) is a data bank and data analysis center, which since 1985 has been jointly sponsored by the US Department of Energy's (US DOE's) Office of Technology Support Programs and Japan's Power Reactor and Nuclear Fuel Development Corporation (PNC). It focuses on reliability, availability and maintainability (RAM) data for components (e.g. valves, pumps, etc.) operating in advanced nuclear reactor facilities. As originally intended, the purpose of the CREDO system was to provide a centralized source of accurate, up-to-date data and information for use in RAM analyses necessary for meeting DOE's data needs in the areas of advanced reactor safety assessments, design and licensing. In particular, creation of the CREDO system was considered an essential element needed to fulfill the DOE Breeder Reactor Safety Program's commitment of 'identifying and exploiting areas in which probabilistic methods can be developed and used in making reactor safety Research and Development choices and optimizing designs of safety systems'. CREDO and its operation are explained. (author)

  3. Application of systems engineering techniques (reliability, availability, maintainability, and dollars) to the Gas Centrifuge Enrichment Plant

    International Nuclear Information System (INIS)

    Boylan, J.G.; DeLozier, R.C.

    1982-01-01

    The systems engineering function for the Gas Centrifuge Enrichment Plant (GCEP) covers system requirements definition, analyses, verification, technical reviews, and other system efforts necessary to assure good balance of performance, safety, cost, and scheduling. The systems engineering function will support the design, installation, start-up, and operational phases of GCEP. The principal objectives of the systems engineering function are to: assure that the system requirements of the GCEP process are adequately specified and documented and that due consideration and emphasis are given to all aspects of the project; provide system analyses of the designs as they progress to assure that system requirements are met and that GCEP interfaces are compatible; assist in the definition of programs for the necessary and sufficient verification of GCEP systems; and integrate reliability, maintainability, logistics, safety, producibility, and other related specialties into a total system effort. This paper addresses the GCEP reliability, availability, maintainability, and dollars (RAM dollars) analyses which are the primary systems engineering tools for the development and implementation of trade-off studies. These studies are basic to reaching cost-effective project decisions. The steps necessary to achieve optimum cost-effective design are shown

  4. Predicting Cost/Reliability/Maintainability of Advanced General Aviation Avionics Equipment

    Science.gov (United States)

    Davis, M. R.; Kamins, M.; Mooz, W. E.

    1978-01-01

    A methodology is provided for assisting NASA in estimating the cost, reliability, and maintenance (CRM) requirements for general avionics equipment operating in the 1980's. Practical problems of predicting these factors are examined. The usefulness and short comings of different approaches for modeling coast and reliability estimates are discussed together with special problems caused by the lack of historical data on the cost of maintaining general aviation avionics. Suggestions are offered on how NASA might proceed in assessing cost reliability CRM implications in the absence of reliable generalized predictive models.

  5. Piping reliability improvement through passive seismic supports

    International Nuclear Information System (INIS)

    Baltus, R.; Rubbers, A.

    1999-01-01

    The nuclear plants designed in the 1970's were equipped with large quantities of snubbers in auxiliary piping systems. The experience revealed a poor performance of snubbers during periodic inspection, while non-nuclear facility piping survived through strong earthquakes. Consequently, seismic design rules evolved towards more realistic criteria and passive dynamic supports were developed to reduce snubber quantities. These solutions improve the pipe reliability during normal operation while reducing the radiation exposure in a sample line is presented with the impact on pipe stresses compared to the results obtained with passive supports named Limit Stops. (author)

  6. Reliability and Maintainability Analysis of a High Air Pressure Compressor Facility

    Science.gov (United States)

    Safie, Fayssal M.; Ring, Robert W.; Cole, Stuart K.

    2013-01-01

    This paper discusses a Reliability, Availability, and Maintainability (RAM) independent assessment conducted to support the refurbishment of the Compressor Station at the NASA Langley Research Center (LaRC). The paper discusses the methodologies used by the assessment team to derive the repair by replacement (RR) strategies to improve the reliability and availability of the Compressor Station (Ref.1). This includes a RAPTOR simulation model that was used to generate the statistical data analysis needed to derive a 15-year investment plan to support the refurbishment of the facility. To summarize, study results clearly indicate that the air compressors are well past their design life. The major failures of Compressors indicate that significant latent failure causes are present. Given the occurrence of these high-cost failures following compressor overhauls, future major failures should be anticipated if compressors are not replaced. Given the results from the RR analysis, the study team recommended a compressor replacement strategy. Based on the data analysis, the RR strategy will lead to sustainable operations through significant improvements in reliability, availability, and the probability of meeting the air demand with acceptable investment cost that should translate, in the long run, into major cost savings. For example, the probability of meeting air demand improved from 79.7 percent for the Base Case to 97.3 percent. Expressed in terms of a reduction in the probability of failing to meet demand (1 in 5 days to 1 in 37 days), the improvement is about 700 percent. Similarly, compressor replacement improved the operational availability of the facility from 97.5 percent to 99.8 percent. Expressed in terms of a reduction in system unavailability (1 in 40 to 1 in 500), the improvement is better than 1000 percent (an order of magnitude improvement). It is worthy to note that the methodologies, tools, and techniques used in the LaRC study can be used to evaluate

  7. Reliability and Maintainability model (RAM) user and maintenance manual. Part 2

    Science.gov (United States)

    Ebeling, Charles E.

    1995-01-01

    This report documents the procedures for utilizing and maintaining the Reliability and Maintainability Model (RAM) developed by the University of Dayton for the NASA Langley Research Center (LaRC). The RAM model predicts reliability and maintainability (R&M) parameters for conceptual space vehicles using parametric relationships between vehicle design and performance characteristics and subsystem mean time between maintenance actions (MTBM) and manhours per maintenance action (MH/MA). These parametric relationships were developed using aircraft R&M data from over thirty different military aircraft of all types. This report describes the general methodology used within the model, the execution and computational sequence, the input screens and data, the output displays and reports, and study analyses and procedures. A source listing is provided.

  8. Solar Energy Grid Integration Systems (SEGIS): adding functionality while maintaining reliability and economics

    Science.gov (United States)

    Bower, Ward

    2011-09-01

    An overview of the activities and progress made during the US DOE Solar Energy Grid Integration Systems (SEGIS) solicitation, while maintaining reliability and economics is provided. The SEGIS R&D opened pathways for interconnecting PV systems to intelligent utility grids and micro-grids of the future. In addition to new capabilities are "value added" features. The new hardware designs resulted in smaller, less material-intensive products that are being viewed by utilities as enabling dispatchable generation and not just unpredictable negative loads. The technical solutions enable "advanced integrated system" concepts and "smart grid" processes to move forward in a faster and focused manner. The advanced integrated inverters/controllers can now incorporate energy management functionality, intelligent electrical grid support features and a multiplicity of communication technologies. Portals for energy flow and two-way communications have been implemented. SEGIS hardware was developed for the utility grid of today, which was designed for one-way power flow, for intermediate grid scenarios, AND for the grid of tomorrow, which will seamlessly accommodate managed two-way power flows as required by large-scale deployment of solar and other distributed generation. The SEGIS hardware and control developed for today meets existing standards and codes AND provides for future connections to a "smart grid" mode that enables utility control and optimized performance.

  9. Recommended techniques for effective maintainability. A continuous improvement initiative of the NASA Reliability and Maintainability Steering Committee

    Science.gov (United States)

    1994-01-01

    This manual presents a series of recommended techniques that can increase overall operational effectiveness of both flight and ground based NASA systems. It provides a set of tools that minimizes risk associated with: (1) restoring failed functions (both ground and flight based); (2) conducting complex and highly visible maintenance operations; and (3) sustaining a technical capability to support the NASA mission using aging equipment or facilities. It considers (1) program management - key elements of an effective maintainability effort; (2) design and development - techniques that have benefited previous programs; (3) analysis and test - quantitative and qualitative analysis processes and testing techniques; and (4) operations and operational design techniques that address NASA field experience. This document is a valuable resource for continuous improvement ideas in executing the systems development process in accordance with the NASA 'better, faster, smaller, and cheaper' goal without compromising safety.

  10. An artificial neural network for modeling reliability, availability and maintainability of a repairable system

    International Nuclear Information System (INIS)

    Rajpal, P.S.; Shishodia, K.S.; Sekhon, G.S.

    2006-01-01

    The paper explores the application of artificial neural networks to model the behaviour of a complex, repairable system. A composite measure of reliability, availability and maintainability parameters has been proposed for measuring the system performance. The artificial neural network has been trained using past data of a helicopter transportation facility. It is used to simulate behaviour of the facility under various constraints. The insights obtained from results of simulation are useful in formulating strategies for optimal operation of the system

  11. A new method for evaluating the availability, reliability, and maintainability whatever may be the probability law

    International Nuclear Information System (INIS)

    Doyon, L.R.; CEA Centre d'Etudes Nucleaires de Saclay, 91 - Gif-sur-Yvette

    1975-01-01

    A simple method is presented for computer solving every system model (availability, reliability, and maintenance) with intervals between failures, and time duration for repairs distributed according to any probability law, and for any maintainance policy. A matrix equation is obtained using Markov diagrams. An example is given with the solution by the APAFS program (Algorithme Pour l'Analyse de la Fiabilite des Systemes) [fr

  12. A Primer for DoD Reliability, Maintainability, Safety, and Logistics Standards, 1992

    Science.gov (United States)

    1991-10-01

    Application of Reliability-Centered Maintenance to Naval Aircraft Weapon Systems and Support Equipment "* FMD -91 Failure Mode/Mechanism...Distributions ( FMD -91) available from the Reliability Analysis Center, HIT Research Institute, 201 Mill St., Rome, NY 13440-8200. 14.4 PHYSICAL...Fault Tree Analysis ( FTA ) (9) Sneak Circuit Analysis (10) Design Reviews Items (1) and (2) are addressed in Section 7 largely by reference to MIL

  13. Increasing the reliability, availability, and maintainability of the AP600 by design

    International Nuclear Information System (INIS)

    Trombola, D.; Meyer, C.

    1993-01-01

    The AP600 design is based on providing a safe, simple, standardized, and economically competitive design with a high degree of operability and ease of maintenance. Design features such as component selection, layout, and standardization increase the probability that targeted repair times are achieved. Design requirements from the utility industry and industry design practices have established criteria for: layout, changeout and replacement of parts and components; access for major pieces of equipment; and vehicle passage. These features coupled with a solid reliability assurance and maintenance program will help the AP600 meet its objectives for operation and maintenance. The AP600 draws on the operating experience and lessons learned from the utility community through design workshops and design review interaction, as well as operating plant data from sources several sources. Internally, the AP600 program incorporates the resources of Westinghouse NSD (Nuclear Service Division), which for decades has provided refueling, steam generator, reactor coolant pump, and other operating plant services. Since the early phases of the design process, the AP600 Program has executed a comprehensive reliability, availability, and maintainability program (RAM) which dealt primarily with assessing and improving plant availability. In conjunction with this program a Probabilistic Risk Assessment (PRA) was performed and submitted to the NRC with the Standard Safety Analysis Report (SSAR) in June 1992. This paper describes how AP600 ensures that the plant has design features to enhance reliability, availability, and maintainability. The RAM program that brings the plant through the design certification phase is described

  14. ETARA PC version 3.3 user's guide: Reliability, availability, maintainability simulation model

    Science.gov (United States)

    Hoffman, David J.; Viterna, Larry A.

    1991-01-01

    A user's manual describing an interactive, menu-driven, personal computer based Monte Carlo reliability, availability, and maintainability simulation program called event time availability reliability (ETARA) is discussed. Given a reliability block diagram representation of a system, ETARA simulates the behavior of the system over a specified period of time using Monte Carlo methods to generate block failure and repair intervals as a function of exponential and/or Weibull distributions. Availability parameters such as equivalent availability, state availability (percentage of time as a particular output state capability), continuous state duration and number of state occurrences can be calculated. Initial spares allotment and spares replenishment on a resupply cycle can be simulated. The number of block failures are tabulated both individually and by block type, as well as total downtime, repair time, and time waiting for spares. Also, maintenance man-hours per year and system reliability, with or without repair, at or above a particular output capability can be calculated over a cumulative period of time or at specific points in time.

  15. Establishing monitoring programs for travel time reliability. [supporting datasets

    Science.gov (United States)

    2014-01-01

    The objective of this project was to develop system designs for programs to monitor travel time reliability and to prepare a guidebook that practitioners and others can use to design, build, operate, and maintain such systems. Generally, such travel ...

  16. Design and reliability, availability, maintainability, and safety analysis of a high availability quadruple vital computer system

    Institute of Scientific and Technical Information of China (English)

    Ping TAN; Wei-ting HE; Jia LIN; Hong-ming ZHAO; Jian CHU

    2011-01-01

    With the development of high-speed railways in China,more than 2000 high-speed trains will be put into use.Safety and efficiency of railway transportation is increasingly important.We have designed a high availability quadruple vital computer (HAQVC) system based on the analysis of the architecture of the traditional double 2-out-of-2 system and 2-out-of-3 system.The HAQVC system is a system with high availability and safety,with prominent characteristics such as fire-new internal architecture,high efficiency,reliable data interaction mechanism,and operation state change mechanism.The hardware of the vital CPU is based on ARM7 with the real-time embedded safe operation system (ES-OS).The Markov modeling method is designed to evaluate the reliability,availability,maintainability,and safety (RAMS) of the system.In this paper,we demonstrate that the HAQVC system is more reliable than the all voting triple modular redundancy (AVTMR) system and double 2-out-of-2 system.Thus,the design can be used for a specific application system,such as an airplane or high-speed railway system.

  17. Work accommodations and natural supports for maintaining employment.

    Science.gov (United States)

    Corbière, Marc; Villotti, Patrizia; Lecomte, Tania; Bond, Gary R; Lesage, Alain; Goldner, Elliot M

    2014-06-01

    Job tenure for people with severe mental disorders, even for those enrolled in supported employment programs, is typically brief. Few studies to date have investigated the relationship between accommodations and natural supports available in the workplace, and job tenure for this population. The main objectives of this study were to develop and to validate a new measure to describe work accommodations and natural supports available in the workplace and to determine which of them are significantly related to job tenure for participants enrolled in supported employment services. In total, 124 people with a severe mental disorder enrolled in supported employment programs and who obtained only one competitive employment at the 9-month follow-up answered the Work Accommodation and Natural Support Scale (WANSS). They also provided information regarding their disclosure (or non-) of mental disorders in the workplace and the length of their job tenure. Confirmatory factor analysis conducted on the WANSS showed 40 items distributed on 6 dimensions (e.g., Schedule flexibility). Correlation results showed that disclosure was significantly related to the number of work accommodations and natural supports available in the workplace. Survival analyses indicated that one WANSS dimension was more salient in predicting job tenure: Supervisor and coworker supports. The WANSS is a valid and useful tool to assess work accommodations and natural supports available in the workplace that employment specialists could use in their practice.

  18. Experiences from maintaining the reliability of a nuclear standby diesel generator system

    International Nuclear Information System (INIS)

    Tammi, P.

    1982-01-01

    The nuclear standby diesel generator system is quite complicated comprising several mechanical and electrotechnical components, on which the reliability of the system is depending. It is an important support system of the plant safety system, and like the safety system it is composed of separate redundant units. The Loviisa nuclear power station has eight diesel generators. The first four of them were taken into operation in 1976. When the frequency of some mechanical failures showed increase, a project was started at the end of 1980 with the intention to find out potential failure possibilities and means for prevention of failures. The work has been mainly concentrated on improving the reliability of the diesel engines. (Auth.)

  19. Supporting farmers in maintaining and selecting seeds of local varieties

    NARCIS (Netherlands)

    Almekinders, C.J.M.; Louwaars, N.P.

    2009-01-01

    This book addresses strategies and approaches through which professionals can support informal seed supply, and link these with the conservation and use of the huge genetic resource base of crops and local varieties. The aim of all the strategies, case studies and reflections on experiences

  20. Reliability and Maintainability Analysis for the Amine Swingbed Carbon Dioxide Removal System

    Science.gov (United States)

    Dunbar, Tyler

    2016-01-01

    I have performed a reliability & maintainability analysis for the Amine Swingbed payload system. The Amine Swingbed is a carbon dioxide removal technology that has gone through 2,400 hours of International Space Station on-orbit use between 2013 and 2016. While the Amine Swingbed is currently an experimental payload system, the Amine Swingbed may be converted to system hardware. If the Amine Swingbed becomes system hardware, it will supplement the Carbon Dioxide Removal Assembly (CDRA) as the primary CO2 removal technology on the International Space Station. NASA is also considering using the Amine Swingbed as the primary carbon dioxide removal technology for future extravehicular mobility units and for the Orion, which will be used for the Asteroid Redirect and Journey to Mars missions. The qualitative component of the reliability and maintainability analysis is a Failure Modes and Effects Analysis (FMEA). In the FMEA, I have investigated how individual components in the Amine Swingbed may fail, and what the worst case scenario is should a failure occur. The significant failure effects are the loss of ability to remove carbon dioxide, the formation of ammonia due to chemical degradation of the amine, and loss of atmosphere because the Amine Swingbed uses the vacuum of space to regenerate the Amine Swingbed. In the quantitative component of the reliability and maintainability analysis, I have assumed a constant failure rate for both electronic and nonelectronic parts. Using this data, I have created a Poisson distribution to predict the failure rate of the Amine Swingbed as a whole. I have determined a mean time to failure for the Amine Swingbed to be approximately 1,400 hours. The observed mean time to failure for the system is between 600 and 1,200 hours. This range includes initial testing of the Amine Swingbed, as well as software faults that are understood to be non-critical. If many of the commercial parts were switched to military-grade parts, the expected

  1. Nutritional support to maintain proper immune status during intense training.

    Science.gov (United States)

    Gleeson, Michael

    2013-01-01

    Prolonged exercise and heavy training are associated with depressed immune function which can increase the risk of picking up minor infections. To maintain robust immunity, athletes should eat a well-balanced diet sufficient to meet their energy, carbohydrate, protein, and micronutrient requirements. Dietary deficiencies of protein and specific micronutrients have long been associated with immune dysfunction and an adequate intake of iron, zinc, and vitamins A, D, E, B6 and B12 is particularly important in the maintenance of immune function. Consuming carbohydrate during prolonged strenuous exercise attenuates rises in stress hormones and appears to limit the degree of exercise-induced immune depression. Similar effects can be seen with daily ingestion of high-dose antioxidant vitamin supplements, though concerns have been expressed that excessive antioxidant intake may impair exercise training adaptations. It is safe to say with reasonable confidence that individual amino acids, colostrum, Echinacea, and zinc are unlikely to boost immunity or reduce infection risk in athletes. The ingestion of carbohydrate during exercise and daily consumption of probiotic and plant polyphenol (e.g. quercetin)-containing supplements or foodstuffs (e.g. non-alcoholic beer) currently offer the best chance of success. This approach is likely to be most effective for individuals who are particularly prone to illness. Copyright © 2013 Nestec Ltd., Vevey/S. Karger AG, Basel.

  2. 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.

  3. Management of reliability and maintainability; a disciplined approach to fleet readiness

    Science.gov (United States)

    Willoughby, W. J., Jr.

    1981-01-01

    Material acquisition fundamentals were reviewed and include: mission profile definition, stress analysis, derating criteria, circuit reliability, failure modes, and worst case analysis. Military system reliability was examined with emphasis on the sparing of equipment. The Navy's organizational strategy for 1980 is presented.

  4. Reliability analysis of idealized tunnel support system using probability-based methods with case studies

    Science.gov (United States)

    Gharouni-Nik, Morteza; Naeimi, Meysam; Ahadi, Sodayf; Alimoradi, Zahra

    2014-06-01

    In order to determine the overall safety of a tunnel support lining, a reliability-based approach is presented in this paper. Support elements in jointed rock tunnels are provided to control the ground movement caused by stress redistribution during the tunnel drive. Main support elements contribute to stability of the tunnel structure are recognized owing to identify various aspects of reliability and sustainability in the system. The selection of efficient support methods for rock tunneling is a key factor in order to reduce the number of problems during construction and maintain the project cost and time within the limited budget and planned schedule. This paper introduces a smart approach by which decision-makers will be able to find the overall reliability of tunnel support system before selecting the final scheme of the lining system. Due to this research focus, engineering reliability which is a branch of statistics and probability is being appropriately applied to the field and much effort has been made to use it in tunneling while investigating the reliability of the lining support system for the tunnel structure. Therefore, reliability analysis for evaluating the tunnel support performance is the main idea used in this research. Decomposition approaches are used for producing system block diagram and determining the failure probability of the whole system. Effectiveness of the proposed reliability model of tunnel lining together with the recommended approaches is examined using several case studies and the final value of reliability obtained for different designing scenarios. Considering the idea of linear correlation between safety factors and reliability parameters, the values of isolated reliabilities determined for different structural components of tunnel support system. In order to determine individual safety factors, finite element modeling is employed for different structural subsystems and the results of numerical analyses are obtained in

  5. Waste Feed Delivery System Phase 1 Preliminary Reliability and Availability and Maintainability Analysis [SEC 1 and 2

    Energy Technology Data Exchange (ETDEWEB)

    CARLSON, A.B.

    1999-11-11

    The document presents updated results of the preliminary reliability, availability, maintainability analysis performed for delivery of waste feed from tanks 241-AZ-101 and 241-AN-105 to British Nuclear Fuels Limited, inc. under the Tank Waste Remediation System Privatization Contract. The operational schedule delay risk is estimated and contributing factors are discussed.

  6. Waste Feed Delivery System Phase 1 Preliminary Reliability and Availability and Maintainability Analysis [SEC 1 and 2

    International Nuclear Information System (INIS)

    CARLSON, A.B.

    1999-01-01

    The document presents updated results of the preliminary reliability, availability, maintainability analysis performed for delivery of waste feed from tanks 241-AZ-101 and 241-AN-105 to British Nuclear Fuels Limited, inc. under the Tank Waste Remediation System Privatization Contract. The operational schedule delay risk is estimated and contributing factors are discussed

  7. 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.

  8. Fast Monte Carlo reliability evaluation using support vector machine

    International Nuclear Information System (INIS)

    Rocco, Claudio M.; Moreno, Jose Ali

    2002-01-01

    This paper deals with the feasibility of using support vector machine (SVM) to build empirical models for use in reliability evaluation. The approach takes advantage of the speed of SVM in the numerous model calculations typically required to perform a Monte Carlo reliability evaluation. The main idea is to develop an estimation algorithm, by training a model on a restricted data set, and replace system performance evaluation by a simpler calculation, which provides reasonably accurate model outputs. The proposed approach is illustrated by several examples. Excellent system reliability results are obtained by training a SVM with a small amount of information

  9. Space Station Freedom power - A reliability, availability, and maintainability assessment of the proposed Space Station Freedom electric power system

    Science.gov (United States)

    Turnquist, S. R.; Twombly, M.; Hoffman, D.

    1989-01-01

    A preliminary reliability, availability, and maintainability (RAM) analysis of the proposed Space Station Freedom electric power system (EPS) was performed using the unit reliability, availability, and maintainability (UNIRAM) analysis methodology. Orbital replacement units (ORUs) having the most significant impact on EPS availability measures were identified. Also, the sensitivity of the EPS to variations in ORU RAM data was evaluated for each ORU. Estimates were made of average EPS power output levels and availability of power to the core area of the space station. The results of assessments of the availability of EPS power and power to load distribution points in the space stations are given. Some highlights of continuing studies being performed to understand EPS availability considerations are presented.

  10. Basic conceptions for development of new-type high-efficiency cooling towers with enhanced reliability, maneuverability and maintainability

    International Nuclear Information System (INIS)

    Kim En Be; Nedviga, Yu.S.

    1990-01-01

    The state-of-the-art of cooling tower design, construction and operation is analysed. From the analysis formulated are general requirements which can be imposed upon cooling towers serving as most important technological apparatuses in water supply systems of thermal and nuclear power plants. With these requirements taken into account, basic research and technical conceptions are developed to be used in designing new-type cooling towers characterized by enhanced reliability, maneuverability and maintainability

  11. John F. Kennedy Space Center, Safety, Reliability, Maintainability and Quality Assurance, Survey and Audit Program

    Science.gov (United States)

    1994-01-01

    This document is the product of the KSC Survey and Audit Working Group composed of civil service and contractor Safety, Reliability, and Quality Assurance (SR&QA) personnel. The program described herein provides standardized terminology, uniformity of survey and audit operations, and emphasizes process assessments rather than a program based solely on compliance. The program establishes minimum training requirements, adopts an auditor certification methodology, and includes survey and audit metrics for the audited organizations as well as the auditing organization.

  12. User's manual of a support system for human reliability analysis

    International Nuclear Information System (INIS)

    Yokobayashi, Masao; Tamura, Kazuo.

    1995-10-01

    Many kinds of human reliability analysis (HRA) methods have been developed. However, users are required to be skillful so as to use them, and also required complicated works such as drawing event tree (ET) and calculation of uncertainty bounds. Moreover, each method is not so complete that only one method of them is not enough to evaluate human reliability. Therefore, a personal computer (PC) based support system for HRA has been developed to execute HRA practically and efficiently. The system consists of two methods, namely, simple method and detailed one. The former uses ASEP that is a simplified THERP-technique, and combined method of OAT and HRA-ET/DeBDA is used for the latter. Users can select a suitable method for their purpose. Human error probability (HEP) data were collected and a database of them was built to use for the support system. This paper describes outline of the HRA methods, support functions and user's guide of the system. (author)

  13. [The external evaluation of study quality: the role in maintaining the reliability of laboratory information].

    Science.gov (United States)

    Men'shikov, V V

    2013-08-01

    The external evaluation of quality of clinical laboratory examinations was gradually introduced in USSR medical laboratories since 1970s. In Russia, in the middle of 1990 a unified all-national system of external evaluation quality was organized known as the Federal center of external evaluation of quality at the basis of laboratory of the state research center of preventive medicine. The main positions of policy in this area were neatly formulated in the guidance documents of ministry of Health. Nowadays, the center of external evaluation of quality proposes 100 and more types of control studies and permanently extends their specter starting from interests of different disciplines of clinical medicine. The consistent participation of laboratories in the cycles of external evaluation of quality intrinsically promotes improvement of indicators of properness and precision of analysis results and increases reliability of laboratory information. However, a significant percentage of laboratories does not participate at all in external evaluation of quality or takes part in control process irregularly and in limited number of tests. The managers of a number of medical organizations disregard the application of the proposed possibilities to increase reliability of laboratory information and limit financing of studies in the field of quality control. The article proposes to adopt the national standard on the basis of ISO 17043 "Evaluation of compliance. The common requirements of professional competence testing".

  14. An information system supporting design for reliability and maintenance

    Energy Technology Data Exchange (ETDEWEB)

    Rit, J.F.; Beraud, M.T

    1997-12-31

    EDF is currently developing a methodology to integrate availability, operating experience and maintenance in the design of power plants. This involves studies that depend closely on the results and assumptions of each other about the reliability and operations of the plant. Therefore a support information system must be carefully designed. Concurrently with development of the methodology, a research oriented information system was designed and built. It is based on the database model of a logistic support repository that we tailored to our needs. (K.A.) 10 refs.

  15. An information system supporting design for reliability and maintenance

    International Nuclear Information System (INIS)

    Rit, J.F.; Beraud, M.T.

    1997-01-01

    EDF is currently developing a methodology to integrate availability, operating experience and maintenance in the design of power plants. This involves studies that depend closely on the results and assumptions of each other about the reliability and operations of the plant. Therefore a support information system must be carefully designed. Concurrently with development of the methodology, a research oriented information system was designed and built. It is based on the database model of a logistic support repository that we tailored to our needs. (K.A.)

  16. Reliability of decision-support systems for nuclear emergency management

    Energy Technology Data Exchange (ETDEWEB)

    Ionescu, Tudor B.

    2013-08-15

    Decision support systems for nuclear emergency management (DSNE) are currently used worldwide to assist decision makers in taking emergency response countermeasures in case of accidental releases of radioactive materials from nuclear facilities. The present work has been motivated by the fact that, up until now, DSNE systems have not been regarded as safetycritical software systems, such as embedded software currently being used in vehicles and aircraft. The core of any DSNE system is represented by the different simulation codes linked together to form the dispersion simulation workflow. These codes require input emission and meteorological data to produce forecasts of the atmospheric dispersion of radioactive pollutants and other substances. However, the reliability of the system not only depends on the trustworthiness of the measured (or generated) input data but also on the reliability of the simulation codes used. The main goal of this work is to improve the reliability of DSNE systems by adapting current state of the art methods from the domain of software reliability engineering to the case of atmospheric dispersion simulation codes. The current approach is based on the design by diversity principle for improving the reliability of codes and the trustworthiness of results as well as on a flexible fault-tolerant workflow scheduling algorithm for ensuring the maximum availability of the system. The author's contribution is represented by (i) an acceptance test for dispersion simulation results, (ii) an adjudication algorithm (voter) based on comparing taxonomies of dispersion simulation results, and (iii) a feedback-control based fault-tolerant workflow scheduling algorithm. These tools provide means for the continuous verification of dispersion simulation codes while tolerating timing faults caused by disturbances in the underlying computational environment and will thus help increase the reliability and trustworthiness of DSNE systems in missioncritical

  17. Reliability of decision-support systems for nuclear emergency management

    International Nuclear Information System (INIS)

    Ionescu, Tudor B.

    2013-08-01

    Decision support systems for nuclear emergency management (DSNE) are currently used worldwide to assist decision makers in taking emergency response countermeasures in case of accidental releases of radioactive materials from nuclear facilities. The present work has been motivated by the fact that, up until now, DSNE systems have not been regarded as safetycritical software systems, such as embedded software currently being used in vehicles and aircraft. The core of any DSNE system is represented by the different simulation codes linked together to form the dispersion simulation workflow. These codes require input emission and meteorological data to produce forecasts of the atmospheric dispersion of radioactive pollutants and other substances. However, the reliability of the system not only depends on the trustworthiness of the measured (or generated) input data but also on the reliability of the simulation codes used. The main goal of this work is to improve the reliability of DSNE systems by adapting current state of the art methods from the domain of software reliability engineering to the case of atmospheric dispersion simulation codes. The current approach is based on the design by diversity principle for improving the reliability of codes and the trustworthiness of results as well as on a flexible fault-tolerant workflow scheduling algorithm for ensuring the maximum availability of the system. The author's contribution is represented by (i) an acceptance test for dispersion simulation results, (ii) an adjudication algorithm (voter) based on comparing taxonomies of dispersion simulation results, and (iii) a feedback-control based fault-tolerant workflow scheduling algorithm. These tools provide means for the continuous verification of dispersion simulation codes while tolerating timing faults caused by disturbances in the underlying computational environment and will thus help increase the reliability and trustworthiness of DSNE systems in missioncritical

  18. The Need to Support and Maintain Legacy Software: Ensuring Ongoing Support for the Isotopics Codes

    International Nuclear Information System (INIS)

    Weber, A.-L.; Funk, P.; McGinnis, B.; Vo, D.; Wang, T.-F.; Peerani, P.; Zsigrai, J.; )

    2015-01-01

    Since about four decades, gamma evaluation codes for plutonium and uranium isotope abundance measurements are a key component of international, regional and domestic safeguards inspections. However, the development of these codes still relies upon a very limited number of experts. This led the safeguards authorities to express concerns, and to request continuity of knowledge and maintenance capability for the codes. The presentation describes initiatives undertaken in the past ten years to ensure ongoing support for the isotopic codes. As a follow-up to the 2005 international workshop, the IAEA issued a roadmap for future developments of gamma codes, followed by a request for support in this field to several MSSP's (namely JNT A 01684). The international working group on gamma spectrometry techniques for U and Pu isotopics (IWG-GST) was launched by the European, French and US MSSPs in 2007, to respond to the needs expressed by the IAEA and other national or international inspectorates. Its activities started with the organization in 2008 of a workshop on gamma spectrometry analysis codes for U and Pu isotopics. The working group is currently developing an international database of reference spectra that will be made available to the community of users and developers. In parallel, IRSN contributes to the JNT A 01684 by advising the IAEA on establishing a procedure for validating a new version of isotopics codes compared to the previous version. The most recent initiative, proposed by the IAEA, consists in organizing an inter-comparison exercise to assess the performances of U and Pu isotopics and mass assay techniques based on medium resolution gamma spectrometry (MRGS). All these initiatives contributed to the continuity of knowledge and maintenance of the gamma isotopic codes, but further efforts are needed to ensure the long-term sustainability of the codes. (author)

  19. Product manufacturing, quality, and reliability initiatives to maintain a competitive advantage and meet customer expectations in the semiconductor industry

    Science.gov (United States)

    Capps, Gregory

    Semiconductor products are manufactured and consumed across the world. The semiconductor industry is constantly striving to manufacture products with greater performance, improved efficiency, less energy consumption, smaller feature sizes, thinner gate oxides, and faster speeds. Customers have pushed towards zero defects and require a more reliable, higher quality product than ever before. Manufacturers are required to improve yields, reduce operating costs, and increase revenue to maintain a competitive advantage. Opportunities exist for integrated circuit (IC) customers and manufacturers to work together and independently to reduce costs, eliminate waste, reduce defects, reduce warranty returns, and improve quality. This project focuses on electrical over-stress (EOS) and re-test okay (RTOK), two top failure return mechanisms, which both make great defect reduction opportunities in customer-manufacturer relationship. Proactive continuous improvement initiatives and methodologies are addressed with emphasis on product life cycle, manufacturing processes, test, statistical process control (SPC), industry best practices, customer education, and customer-manufacturer interaction.

  20. Incremental support vector machines for fast reliable image recognition

    International Nuclear Information System (INIS)

    Makili, L.; Vega, J.; Dormido-Canto, S.

    2013-01-01

    Highlights: ► A conformal predictor using SVM as the underlying algorithm was implemented. ► It was applied to image recognition in the TJ–II's Thomson Scattering Diagnostic. ► To improve time efficiency an approach to incremental SVM training has been used. ► Accuracy is similar to the one reached when standard SVM is used. ► Computational time saving is significant for large training sets. -- Abstract: This paper addresses the reliable classification of images in a 5-class problem. To this end, an automatic recognition system, based on conformal predictors and using Support Vector Machines (SVM) as the underlying algorithm has been developed and applied to the recognition of images in the Thomson Scattering Diagnostic of the TJ–II fusion device. Using such conformal predictor based classifier is a computationally intensive task since it implies to train several SVM models to classify a single example and to perform this training from scratch takes a significant amount of time. In order to improve the classification time efficiency, an approach to the incremental training of SVM has been used as the underlying algorithm. Experimental results show that the overall performance of the new classifier is high, comparable to the one corresponding to the use of standard SVM as the underlying algorithm and there is a significant improvement in time efficiency

  1. Incremental support vector machines for fast reliable image recognition

    Energy Technology Data Exchange (ETDEWEB)

    Makili, L., E-mail: makili_le@yahoo.com [Instituto Superior Politécnico da Universidade Katyavala Bwila, Benguela (Angola); Vega, J. [Asociación EURATOM/CIEMAT para Fusión, Madrid (Spain); Dormido-Canto, S. [Dpto. Informática y Automática – UNED, Madrid (Spain)

    2013-10-15

    Highlights: ► A conformal predictor using SVM as the underlying algorithm was implemented. ► It was applied to image recognition in the TJ–II's Thomson Scattering Diagnostic. ► To improve time efficiency an approach to incremental SVM training has been used. ► Accuracy is similar to the one reached when standard SVM is used. ► Computational time saving is significant for large training sets. -- Abstract: This paper addresses the reliable classification of images in a 5-class problem. To this end, an automatic recognition system, based on conformal predictors and using Support Vector Machines (SVM) as the underlying algorithm has been developed and applied to the recognition of images in the Thomson Scattering Diagnostic of the TJ–II fusion device. Using such conformal predictor based classifier is a computationally intensive task since it implies to train several SVM models to classify a single example and to perform this training from scratch takes a significant amount of time. In order to improve the classification time efficiency, an approach to the incremental training of SVM has been used as the underlying algorithm. Experimental results show that the overall performance of the new classifier is high, comparable to the one corresponding to the use of standard SVM as the underlying algorithm and there is a significant improvement in time efficiency.

  2. Maintaining normality and support are central issues when receiving chemotherapy for ovarian cancer.

    Science.gov (United States)

    Ekman, Inger; Bergbom, Ingegerd; Ekman, Tor; Berthold, Harrieth; Mahsneh, Sawsan Majali

    2004-01-01

    The aim of this study was to enrich the understanding of patients' perspective of being diagnosed and treated for ovarian cancer. A qualitative approach was used to obtain knowledge and insight into patients' experiences and thoughts. Ten Swedish women, diagnosed with ovarian cancer, participated in a total of 23 interviews on 3 occasions: at the time of diagnosis, during chemotherapy, and after completion of chemotherapy. The results of the interpretation of the interviews were formulated in the form of 3 themes: (1) feeling the same despite radical castrating surgery, (2) accepting chemotherapy, and (3) maintaining normality and support. Suggestions of caring implications from our interpretation of the interview data underscore the need to support these women in learning to cope with their feelings of weakness and anxiety. The findings further indicate the potential in narrative methods to identify important issues in comprehensive cancer care.

  3. Pilot testing of SHRP 2 reliability data and analytical products: Southern California. [supporting datasets

    Science.gov (United States)

    2014-01-01

    The objective of this project was to develop system designs for programs to monitor travel time reliability and to prepare a guidebook that practitioners and others can use to design, build, operate, and maintain such systems. Generally, such travel ...

  4. Four-train support always more reliable than a two-train support?

    International Nuclear Information System (INIS)

    Guey, C.N.; Arrieta, L.; Youngblood, R.

    1986-01-01

    Once the gross features of a frontline fluid system have been defined, one must consider what support system configuration will provide the best overall system performance. This paper considers different direct-current (dc) bus configurations for a given emergency feedwater system (EFWS). Results indicate that a four-train support system (i.e., 4 dc buses) gives a lower system unavailability for transients, but a higher system unavailability for anticipated transients without scram (ATWSs), than a two-train support system (i.e., two dc buses). This serves to illustrate that more trains do not necessarily provide higher reliability, and that a configuration choice which is better for one emission success criterion may be worse for another. Because of the small characteristic unreliability of dc buses, the numerical comparisons made here are not dramatic, but the underlying topological point is nevertheless broadly applicable

  5. Maintaining adequate nutrient supply - Principles, decision-support tools, and best management practices [Chapter 6

    Science.gov (United States)

    Robert B. Harrison; Douglas A. Maguire; Deborah Page-Dumroese

    2011-01-01

    Maintaining adequate nutrient supply to maintain or enhance tree vigor and forest growth requires conservation of topsoil and soil organic matter. Sometimes nutrient amendments are also required to supplement inherent nutrient-pool limitations or replenish nutrients removed in harvested material. The goal is to maintain the productive potential of the soil and, when...

  6. Groningen orthopaedic social support scale: Validity and reliability

    NARCIS (Netherlands)

    van den Akker-Scheek, I.; Stevens, M.; Spriensma, A.; van Horn, J.R.

    2004-01-01

    BACKGROUND: Social support is an important factor in the rehabilitation process, as it has a positive influence on patients' health, functioning and recovery. In particular, perceived social support and instrumental support are important after total hip or knee arthroplasty. However, nursing staff

  7. 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.

  8. Integrated approach for combining sustainability and safety into a RAM analysis, RAM2S (Reliability, Availability, Maintainability, Sustainability and Safety) towards greenhouse gases emission targets

    Energy Technology Data Exchange (ETDEWEB)

    Alvarenga, Tobias V. [Det Norske Veritas (DNV), Hovik, Oslo (Norway)

    2009-07-01

    This paper aims to present an approach to integrate sustainability and safety concerns on top of a typical RAM Analysis to support new enterprises to find alternatives to align themselves to the greenhouse gases emission targets, measured as CO{sub 2} (carbon dioxide) equivalent. This approach can be used to measure the impact of the potential CO{sub 2} equivalent emission levels mainly related to new enterprises with high CO{sub 2} content towards environment and production, as per example, the extraction of oil and gas from the Brazilian Pre-salt layers. In this sense, this integrated approach, combining Sustainability and Safety into a RAM analysis, RAM2S (Reliability, Availability, Maintainability, Sustainability and Safety), can be used to assess the impact of CO{sub 2} 'production' along the entire enterprise life-cycle, including the impact of possible facility shutdown due to emission restrictions limits, as well as due to the occurrence of additional failures modes related to CO{sub 2} corrosion capabilities. Thus, at the end, this integrated approach would allow companies to find out a more cost-effective alternative to adapt their business into the global warming reality, overcoming the inherent threats of greenhouse gases. (author)

  9. Is a 4-train support ''always'' more reliable than a 2-train support

    International Nuclear Information System (INIS)

    Guey, C.N.; Arrieta, L.; Youngblood, R.

    1986-06-01

    Once the gross features of a frontline fluid system have been defined, one must consider what support system configuration will provide the best overall system performance. This paper considers different dc bus configurations for a given emergency feedwater system. Results indicate that a four-train support system (i.e., 4 dc buses) gives a lower system unavailability for transients, but a higher system unavailability for Anticipated Transients Without Scram (ATWS), than a two-train support system (i.e., two dc buses). This serves to illustrate that more trains do not necessarily provide higher reliability, and that a configuration choice which is better for one mission success criterion may be worse for another. Because of the small characteristic unreliability of dc buses, the numerical comparisons made here are not dramatic, but the underlying topological point is nevertheless broadly applicable. The EFWS selected in this study consists of two turbine-driven pumps, and two motor-driven pumps, with associated piping, instruments, and valves. There are two divisions of EFWS, each division including one turbine-driven pump train, and one motor-driven pump train with a crosstie that can provide an alternate flow path in case one train is not available. Each of the motor-driven pumps has one ac power bus associated with it. No ac power is required for the turbine-driven trains

  10. 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...

  11. 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.

  12. Further HTGR core support structure reliability studies. Interim report No. 1

    International Nuclear Information System (INIS)

    Platus, D.L.

    1976-01-01

    Results of a continuing effort to investigate high temperature gas cooled reactor (HTGR) core support structure reliability are described. Graphite material and core support structure component physical, mechanical and strength properties required for the reliability analysis are identified. Also described are experimental and associated analytical techniques for determining the required properties, a procedure for determining number of tests required, properties that might be monitored by special surveillance of the core support structure to improve reliability predictions, and recommendations for further studies. Emphasis in the study is directed towards developing a basic understanding of graphite failure and strength degradation mechanisms; and validating analytical methods for predicting strength and strength degradation from basic material properties

  13. Supportive periodontal therapy (SPT) for maintaining the dentition in adults treated for periodontitis.

    Science.gov (United States)

    Manresa, Carolina; Sanz-Miralles, Elena C; Twigg, Joshua; Bravo, Manuel

    2018-01-01

    Periodontitis is a bacterially-induced, chronic inflammatory disease that destroys the connective tissues and bone that support teeth. Active periodontal treatment aims to reduce the inflammatory response, primarily through eradication of bacterial deposits. Following completion of treatment and arrest of inflammation, supportive periodontal therapy (SPT) is employed to reduce the probability of re-infection and progression of the disease; to maintain teeth without pain, excessive mobility or persistent infection in the long term, and to prevent related oral diseases.According to the American Academy of Periodontology, SPT should include all components of a typical dental recall examination, and importantly should also include periodontal re-evaluation and risk assessment, supragingival and subgingival removal of bacterial plaque and calculus, and re-treatment of any sites showing recurrent or persistent disease. While the first four points might be expected to form part of the routine examination appointment for periodontally healthy patients, the inclusion of thorough periodontal evaluation, risk assessment and subsequent treatment - normally including mechanical debridement of any plaque or calculus deposits - differentiates SPT from routine care.Success of SPT has been reported in a number of long-term, retrospective studies. This review aimed to assess the evidence available from randomised controlled trials (RCTs). To determine the effects of supportive periodontal therapy (SPT) in the maintenance of the dentition of adults treated for periodontitis. Cochrane Oral Health's Information Specialist searched the following databases: Cochrane Oral Health's Trials Register (to 8 May 2017), the Cochrane Central Register of Controlled Trials (CENTRAL) (the Cochrane Library, 2017, Issue 5), MEDLINE Ovid (1946 to 8 May 2017), and Embase Ovid (1980 to 8 May 2017). The US National Institutes of Health Trials Registry (ClinicalTrials.gov) and the World Health Organization

  14. Supporting change processes in design: Complexity, prediction and reliability

    Energy Technology Data Exchange (ETDEWEB)

    Eckert, Claudia M. [Engineering Design Centre, University of Cambridge, Trumpington Street, Cambridge, CB2 1PZ (United Kingdom)]. E-mail: cme26@cam.ac.uk; Keller, Rene [Engineering Design Centre, University of Cambridge, Trumpington Street, Cambridge, CB2 1PZ (United Kingdom)]. E-mail: rk313@cam.ac.uk; Earl, Chris [Open University, Department of Design and Innovation, Walton Hall, Milton Keynes MK7 6AA (United Kingdom)]. E-mail: C.F.Earl@open.ac.uk; Clarkson, P. John [Engineering Design Centre, University of Cambridge, Trumpington Street, Cambridge, CB2 1PZ (United Kingdom)]. E-mail: pjc10@cam.ac.uk

    2006-12-15

    Change to existing products is fundamental to design processes. New products are often designed through change or modification to existing products. Specific parts or subsystems are changed to similar ones whilst others are directly reused. Design by modification applies particularly to safety critical products where the reuse of existing working parts and subsystems can reduce cost and risk. However change is rarely a matter of just reusing or modifying parts. Changing one part can propagate through the entire design leading to costly rework or jeopardising the integrity of the whole product. This paper characterises product change based on studies in the aerospace and automotive industry and introduces tools to aid designers in understanding the potential effects of change. Two ways of supporting designers are described: probabilistic prediction of the effects of change and visualisation of change propagation through product connectivities. Change propagation has uncertainties which are amplified by the choices designers make in practice as they implement change. Change prediction and visualisation is discussed with reference to complexity in three areas of product development: the structural backcloth of connectivities in the existing product (and its processes), the descriptions of the product used in design and the actions taken to carry out changes.

  15. Survey of the possibilities to maintain correct measurements through increased reliability of components or through ''operational fault perceptibility''

    International Nuclear Information System (INIS)

    Volkmann, C.U.

    1982-12-01

    Tests and requirements for the pattern approval of mechanical weighing machines are based on long-term experience and detailed regulations, whereas equivalent treatment of electronic devices of weighing machines is a new kind of task. In this field experience is still scarce, and regulations are lacking. While there is some unanimity that the sensitivity of electronic devices to any kind of electromagnetic interferences has to be judged on the grounds of some tests, there is no universally accepted guideline as to how to assure, over a few weeks of pattern approval tests, the measuring stability for a period of years. Two major concepts are being followed to this end: increased reliability of components and ''operational fault perceptibility (OFP)''. After some remarks concerning the terminology to be used, both concepts are discussed and eventually compared. (orig.)

  16. Reliability analysis of idealized tunnel support system using probability-based methods with case studies

    NARCIS (Netherlands)

    Gharouni-Nik, M.; Naeimi, M.; Ahadi, S.; Alimoradi, Z.

    2014-01-01

    In order to determine the overall safety of a tunnel support lining, a reliability-based approach is presented in this paper. Support elements in jointed rock tunnels are provided to control the ground movement caused by stress redistribution during the tunnel drive. Main support elements contribute

  17. Managing Stress and Maintaining Well-Being: Social Support, Problem-Focused Coping, and Avoidant Coping

    Science.gov (United States)

    Chao, Ruth Chu-Lien

    2011-01-01

    This study tested a model that links stress, social support, problem-focused coping, and well-being. First, it looks at how high support significantly moderated the association between stress and well-being. Next, the students' problem-focused coping was seen as mediating this moderated association. Finally, a 3-way interaction of stress, social…

  18. Long-term Mechanical Circulatory Support System reliability recommendation by the National Clinical Trial Initiative subcommittee.

    Science.gov (United States)

    Lee, James

    2009-01-01

    The Long-Term Mechanical Circulatory Support (MCS) System Reliability Recommendation was published in the American Society for Artificial Internal Organs (ASAIO) Journal and the Annals of Thoracic Surgery in 1998. At that time, it was stated that the document would be periodically reviewed to assess its timeliness and appropriateness within 5 years. Given the wealth of clinical experience in MCS systems, a new recommendation has been drafted by consensus of a group of representatives from the medical community, academia, industry, and government. The new recommendation describes a reliability test methodology and provides detailed reliability recommendations. In addition, the new recommendation provides additional information and clinical data in appendices that are intended to assist the reliability test engineer in the development of a reliability test that is expected to give improved predictions of clinical reliability compared with past test methods. The appendices are available for download at the ASAIO journal web site at www.asaiojournal.com.

  19. Social support: An approach to maintaining the health of women who have experienced stillbirth

    OpenAIRE

    Allahdadian, Maryam; Irajpour, Alireza; Kazemi, Ashraf; Kheirabadi, Gholamreza

    2015-01-01

    Background: Stillbirth is one of the deepest losses that can inflict a broad range of cognitive, mental, spiritual, and physical turmoil. Many researchers believe that the failure to provide the care required by health teams during the hard times is the main determinant of maternal mental health in the future. In other words, social support can significantly improve the mental health outcomes of mothers after stillbirth. This study aimed to explore social support to aid mothers in adaptation ...

  20. Reliability and validity of the perspectives of Support From God Scale.

    Science.gov (United States)

    Hamilton, Jill B; Crandell, Jamie L; Carter, J Kameron; Lynn, Mary R

    2010-01-01

    Existing spiritual support scales for use with cancer survivors focus on the support believed to come from a religious community, clergy, or health care providers. The objective of this study was to evaluate the reliability and validity of a new measure of spiritual support believed to come from God in older Christian African American cancer survivors. The Perceived Support From God Scale was administered to 317 African American cancer survivors aged 55-89 years. Psychometric evaluation involved identifying underlying factors, conducting item analysis and estimating reliability, and obtaining evidence on the relationship to other variables or the extent to which the Perceived Support From God Scale correlates with religious involvement and depression. The Perceived Support From God Scale consists of 15 items in two subscales (Support From God and God's Purpose for Me). The two subscales explained 59% of the variance. Cronbach's alpha coefficients were .94 and .86 for the Support From God and God's Purpose for Me subscales, respectively. Test-retest correlations were strong, supporting the temporal stability of the instrument. Pearson's correlations to an existing religious involvement and beliefs scale were moderate to strong. Subscale scores on Support From God were negatively correlated to depression. Initial support for reliability and validity was demonstrated for the Perceived Support From God Scale. The scale captures a facet of spirituality not emphasized in other measures. Further research is needed to evaluate the scale with persons of other racial/ethnic groups and to explore the relationship of spirituality to other outcome measures.

  1. Examining the Reliability and Validity of the Effective Behavior Support Self-Assessment Survey

    Science.gov (United States)

    Solomon, Benjamin G.; Tobin, Kevin G.; Schutte, Gregory M.

    2015-01-01

    The Effective Behavior Support Self-Assessment Survey (SAS; Sugai, Horner, & Todd, 2003) is designed to measure perceived Positive Behavior Interventions and Supports (PBIS) implementation and identify priorities for improvement. Despite its longevity, little published research exists documenting its reliability or validity for these purposes.…

  2. Monte Carlo simulation - a powerful tool to support experimental activities in structure reliability

    International Nuclear Information System (INIS)

    Yuritzinn, T.; Chapuliot, S.; Eid, M.; Masson, R.; Dahl, A.; Moinereau, D.

    2003-01-01

    Monte-Carlo Simulation (MCS) can have different uses in supporting structure reliability investigations and assessments. In this paper we focus our interest on the use of MCS as a numerical tool to support the fitting of the experimental data related to toughness experiments. (authors)

  3. Measuring participation of social-support clients: : validity and reliability of IPA-MO

    NARCIS (Netherlands)

    Berenschot, L.; Grift, Y.K.

    2017-01-01

    This study evaluates the reliability and validity of the Impact on Autonomy and Participation instrument (IPA) for heterogeneous populations of social support clients. Decentralisation of social support and accompanying budget cuts spurred interest in outcome-related payment systems to foster

  4. Ebb and Flow: Maintaining the Close Air Support Relationship through History

    Science.gov (United States)

    2016-05-10

    3-09.3, Close Air Support (Washington, DC: Government Printing Office, 2014), xi. 20 Scott Fischer , LtCol, USAF, “Army and Air Force Subcultures...also happens that airmen and ground forces can 30 Jeff Schogol, "Welsh: The Air Force cares about...Advanced Military Studies, 2004), 59. 60 Fischer , “Army Air Force Subcultures,” 15. 61 Bolton, “Army Fixed-Wing Attack,” 5-6. 21 external

  5. Using reliability analysis to support decision making\\ud in phased mission systems

    OpenAIRE

    Zhang, Yang; Prescott, Darren

    2017-01-01

    Due to the environments in which they will operate, future autonomous systems must be capable of reconfiguring quickly and safely following faults or environmental changes. Past research has shown how, by considering autonomous systems to perform phased missions, reliability analysis can support decision making by allowing comparison of the probability of success of different missions following reconfiguration. Binary Decision Diagrams (BDDs) offer fast, accurate reliability analysis that cou...

  6. Technophiles to Newbies: The Challenge of Supporting Distributed Teams to Maintain Engagement in Virtual Worlds

    Science.gov (United States)

    Griffith, Karen

    2011-01-01

    The purpose of this paper is to look for links in a virtual trainee's interest and self-efficacy in a simulated event as it relates to their previous self-reported technical skill level. Ultimately, the idea would be to provide the right amount of support at the right place at the right time to set the conditions for maximum transfer of the skill sets to the work place. An anecdotal recap of a recent experiment of a medium-scale training event produced in a virtual world will provide examples for discussion. In July 2010, a virtual training event was produced for the Air Force Research Lab's Games for Team Training (GaMeTT) at the Patriot Exercise at Volk Field in Wisconsin. There were 29 EMEDS participants who completed the simulated OCO event using the OLIVE gaming engine. Approximately 25 avatars were present at any given time; including role players, observers, coordinators and participants.

  7. Maintaining clinical tissue archives and supporting human research: challenges and solutions.

    Science.gov (United States)

    Giannini, Caterina; Oelkers, Michael M; Edwards, William D; Aubry, Marie Christine; Muncil, Maureen M; Mohamud, Koshin H; Sandleback, Sara G; Nowak, John M; Bridgeman, Andrew; Brown, Marie E; Cheville, John C

    2011-03-01

    The increasing number of requests for use of clinically archived tissue in translational research poses unique challenges. Conflicts may arise between pathologists who are responsible for overseeing and preserving the tissues and investigators who need these materials for research purposes. To evaluate the status of our institution's Tissue Registry Archive and to develop updated written policies and procedures to support a new modern and robust tracking system with features of a library loan system. An observational study was performed. We found the existing process for managing loans of tissue (slides and paraffin blocks) to be insufficient for the complexity and volume of this task. After extensive customization, a new tracking system was implemented in January 2008. Analysis of the first year of the system's use (2008) showed that of the 206,330 slides and 51,416 blocks loaned out in 2008, 92% and 94%, respectively, were returned by the due date. These rates were markedly improved from those before the new system: 61% and 47%, respectively, in 2005. Material permanently "lost" in 2008 represented only 0.02% of slides and 0.05% of blocks, none of which was the only diagnostic material for the case. With expanding needs for archived tissues for clinical care and growing demands for translational research, it is essential that pathology departments at institutions with large tissue-based research endeavors have a tracking and management system in place to meet clinical, educational, and research needs, as well as legal requirements.

  8. Maintaining a Local Data Integration System in Support of Weather Forecast Operations

    Science.gov (United States)

    Watson, Leela R.; Blottman, Peter F.; Sharp, David W.; Hoeth, Brian

    2010-01-01

    Since 2000, both the National Weather Service in Melbourne, FL (NWS MLB) and the Spaceflight Meteorology Group (SMG) at Johnson Space Center in Houston, TX have used a local data integration system (LDIS) as part of their forecast and warning operations. The original LDIS was developed by NASA's Applied Meteorology Unit (AMU; Bauman et ai, 2004) in 1998 (Manobianco and Case 1998) and has undergone subsequent improvements. Each has benefited from three-dimensional (3-D) analyses that are delivered to forecasters every 15 minutes across the peninsula of Florida. The intent is to generate products that enhance short-range weather forecasts issued in support of NWS MLB and SMG operational requirements within East Central Florida. The current LDIS uses the Advanced Regional Prediction System (ARPS) Data Analysis System (ADAS) package as its core, which integrates a wide variety of national, regional, and local observational data sets. It assimilates all available real-time data within its domain and is run at a finer spatial and temporal resolution than current national- or regional-scale analysis packages. As such, it provides local forecasters with a more comprehensive understanding of evolving fine-scale weather features

  9. Maintaining a Local Data Integration System in Support of Weather Forecast Operations

    Science.gov (United States)

    Watson, Leela R.; Blottman, Peter F.; Sharp, David W.; Hoeth, Brian

    2010-01-01

    Since 2000, both the National Weather Service in Melbourne, FL (NWS MLB) and the Spaceflight Meteorology Group (SMG) have used a local data integration system (LDIS) as part of their forecast and warning operations. Each has benefited from 3-dimensional analyses that are delivered to forecasters every 15 minutes across the peninsula of Florida. The intent is to generate products that enhance short-range weather forecasts issued in support of NWS MLB and SMG operational requirements within East Central Florida. The current LDIS uses the Advanced Regional Prediction System (ARPS) Data Analysis System (ADAS) package as its core, which integrates a wide variety of national, regional, and local observational data sets. It assimilates all available real-time data within its domain and is run at a finer spatial and temporal resolution than current national- or regional-scale analysis packages. As such, it provides local forecasters with a more comprehensive and complete understanding of evolving fine-scale weather features. Recent efforts have been undertaken to update the LDIS through the formal tasking process of NASA's Applied Meteorology Unit. The goals include upgrading LDIS with the latest version of ADAS, incorporating new sources of observational data, and making adjustments to shell scripts written to govern the system. A series of scripts run a complete modeling system consisting of the preprocessing step, the main model integration, and the post-processing step. The preprocessing step prepares the terrain, surface characteristics data sets, and the objective analysis for model initialization. Data ingested through ADAS include (but are not limited to) Level II Weather Surveillance Radar- 1988 Doppler (WSR-88D) data from six Florida radars, Geostationary Operational Environmental Satellites (GOES) visible and infrared satellite imagery, surface and upper air observations throughout Florida from NOAA's Earth System Research Laboratory/Global Systems Division

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

    Directory of Open Access Journals (Sweden)

    Yu Wang

    2015-01-01

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

  11. Evaluating validity and reliability of Persian version of Supports Intensity Scale in adults with intellectual disability

    Directory of Open Access Journals (Sweden)

    Shahin Soltani

    2013-12-01

    Full Text Available Background: Shifting paradigms regarding the ways to assess the support needs of people with intellectual disability in 1980 necessitates the design and development of appropriate tools more than ever. In this regard, American Association on Intellectual and Developmental Disabilities (AAIDD developed Supports Intensity Scale (SIS to respond the lack of an appropriate measurement tool. The aim of this study is the cultural adaptation and evaluation of psychometric properties of Supports Intensity Scale in adults with intellectual disability. Methods: Validity of Persian version of SIS was assessed by Content validity. The reliability of the scale was evaluated using Cronbach's alpha and test–retest reliability with a 3-week interval. In this study, the sample contained 43 adults (29 men and 14 women with intellectual disability. Results: The content of the Persian version of SIS was approved by the experts. The Cronbach's alpha reliability coefficients for the subscales ranged between 0.80 and 0.99. Also, Intraclass correlation coefficients ranged between 0.90 and 0.99 (P<0.001. Furthermore, all Pearson correlation coefficients among the SIS subscales ranged between 0.63 and 0.98 (P<0.01. Conclusion: The results of this study indicated that the validity and reliability of the equivalent Persian version of SIS for identifying pattern and required supports intensity in adults with intellectual disability is acceptable.

  12. Failure and reliability prediction by support vector machines regression of time series data

    International Nuclear Information System (INIS)

    Chagas Moura, Marcio das; Zio, Enrico; Lins, Isis Didier; Droguett, Enrique

    2011-01-01

    Support Vector Machines (SVMs) are kernel-based learning methods, which have been successfully adopted for regression problems. However, their use in reliability applications has not been widely explored. In this paper, a comparative analysis is presented in order to evaluate the SVM effectiveness in forecasting time-to-failure and reliability of engineered components based on time series data. The performance on literature case studies of SVM regression is measured against other advanced learning methods such as the Radial Basis Function, the traditional MultiLayer Perceptron model, Box-Jenkins autoregressive-integrated-moving average and the Infinite Impulse Response Locally Recurrent Neural Networks. The comparison shows that in the analyzed cases, SVM outperforms or is comparable to other techniques. - Highlights: → Realistic modeling of reliability demands complex mathematical formulations. → SVM is proper when the relation input/output is unknown or very costly to be obtained. → Results indicate the potential of SVM for reliability time series prediction. → Reliability estimates support the establishment of adequate maintenance strategies.

  13. Delivering on Industry Equipment Reliability Goals By Leveraging an Integration Platform and Decision Support Environment

    International Nuclear Information System (INIS)

    Coveney, Maureen K.; Bailey, W. Henry; Parkinson, William

    2004-01-01

    Utilities have invested in many costly enterprise systems - computerized maintenance management systems, document management systems, enterprise grade portals, to name but a few - and often very specialized systems, like data historians, high end diagnostic systems, and other focused and point solutions. From recent industry reports, we now know that the average nuclear power utilizes on average 1900 systems to perform daily work, of which 250 might facilitate the equipment reliability decision-making process. The time has come to leverage the investment in these systems by providing a common platform for integration and decision-making that will further the collective industry aim of enhancing the reliability of our nuclear generation assets to maintain high plant availability and to deliver on plant life extension goals without requiring additional large scale investment in IT infrastructure. (authors)

  14. Development of Chinese Military Personnel Social Support Scale and tests for its reliability and validity

    Directory of Open Access Journals (Sweden)

    Kai-hong TANG

    2013-01-01

    Full Text Available Objective  To develop Chinese Military Personnel Social Support Scaleand verify its reliability and validity. Methods  The Chinese Military Personnel Social Support Scalewas initiated, organized and compiled based upon open-ended questionnaire survey done in a systematic manner, and previous researches were taken as references. A total of 630 military personnel were chosen by random cluster sampling and tested with the Scale, among them 50 were tested with Social Support Rating Scale(SSRS and Chinese Military Psychosomatic Health Scale(CMPHS simultaneously, and the test was done solely a second time with CMPHS 2 weeks later. The reliability and validity were assessed and verified by exploratory factor analysis, confirmatory factor analysis and correlation analysis. Results  The Chinese Military Personnel Social Support Scalecomprised three factors, namely subjective support, objective support and utility of social support. Eighteen items were left in official scale after amendment by factor analysis, and one lying subscale was added. The correlation coefficients between the public factors ranged from 0.477 to 0.589 (P<0.01, and the correlation coefficients between factors and total scale ranged from 0.721 to 0.823 (P<0.01. The test-retest correlation coefficients of total scale and subscales ranged from 0.622 to 0.803 (P<0.01, the Cronbach α coefficients ranged from 0.624 to 0.874, and the split-half correlation coefficients ranged from 0.551 to 0.828. Significant correlation existed between this Scale and two criterion scales, namely SSRS and CMPHS. Conclusion  It is verified that the Chinese Military Personnel Social Support Scalehas excellent reliability and validity, and complying with psychometric standards, it may be used to evaluate the social support level of Chinese military personnel.

  15. Revisiting Frequency Reuse towards Supporting Ultra-Reliable Ubiquitous-Rate Communication

    DEFF Research Database (Denmark)

    Park, Jihong; Kim, Dong Min; Popovski, Petar

    2017-01-01

    One of the goals of 5G wireless systems stated by the NGMN alliance is to provide moderate rates (50+ Mbps) everywhere and with very high reliability. We term this service Ultra-Reliable Ubiquitous-Rate Communication (UR2C). This paper investigates the role of frequency reuse in supporting UR2C...... in the downlink. To this end, two frequency reuse schemes are considered: user-specific frequency reuse (FRu) and BS-specific frequency reuse (FRb). For a given unit frequency channel, FRu reduces the number of serving user equipments (UEs), whereas FRb directly decreases the number of interfering base stations...

  16. Reliability and validity of a physical activity social support assessment scale in adolescents - ASAFA Scale

    Directory of Open Access Journals (Sweden)

    José Cazuza de Farias Júnior

    2014-06-01

    Full Text Available Objective: To analyze the reliability and validity of a scale used to measure social support for physical activity in adolescents - ASAFA Scale. Methods: This study included 2,755 adolescents (57.6% girls, 16.5 ± 1.2 years of age, from Joao Pessoa, Paraiba, Brazil. Initially, the scale was consisted of 12 items (6 for social support from parents and 6 from friends. The reliability of the scale was estimated by Cronbach's alpha coefficient (α, by the Composite Reliability (CR, and by the model with two factors and factorial invariance by Confirmatory Factor Analysis (CFA adequacy. Results: The CFA results confirmed that the social support scale contained two factors (factor 1: social support from parents; factor 2: social support from friends with five items each (one item was excluded from each scale, all with high factor loadings (> 0.65 and acceptable adjustment indexes (RMR = 0.050; RMSEA = 0.063; 90%CI: 0.060 - 0.067; AGFI = 0.903; GFI = 0.940; CFI = 0.934, NNFI = 0.932. The internal consistency was satisfactory (parents: α ≥ 0.77 and CR ≥ 0.83; friends: α ≥ 0.87 and CR ≥ 0.91. The scale's factorial invariance was confirmed (p > 0.05; Δχ2 and ΔCFI ≤ 0.01 across all subgroups analyzed (gender, age, economic class. The construct validity was evidenced by the significant association (p < 0.05 between the adolescents physical activity level and the social support score of parents (rho = 0.29 and friends (rho = 0.39. Conclusions: The scale showed reliability, factorial invariance and satisfactory validity, so it can be used in studies with adolescents.

  17. 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.

  18. Forecasting systems reliability based on support vector regression with genetic algorithms

    International Nuclear Information System (INIS)

    Chen, K.-Y.

    2007-01-01

    This study applies a novel neural-network technique, support vector regression (SVR), to forecast reliability in engine systems. The aim of this study is to examine the feasibility of SVR in systems reliability prediction by comparing it with the existing neural-network approaches and the autoregressive integrated moving average (ARIMA) model. To build an effective SVR model, SVR's parameters must be set carefully. This study proposes a novel approach, known as GA-SVR, which searches for SVR's optimal parameters using real-value genetic algorithms, and then adopts the optimal parameters to construct the SVR models. A real reliability data for 40 suits of turbochargers were employed as the data set. The experimental results demonstrate that SVR outperforms the existing neural-network approaches and the traditional ARIMA models based on the normalized root mean square error and mean absolute percentage error

  19. Tooth loss in well-maintained patients with chronic periodontitis during long-term supportive therapy in Brazil.

    Science.gov (United States)

    Chambrone, Luiz A; Chambrone, Leandro

    2006-10-01

    The objective of this retrospective study was to assess the reasons for tooth loss in a sample of patients who underwent periodontal therapy and supportive periodontal therapy (SPT) in a Brazilian private periodontal practice. A sample of 120 subjects who had been treated and maintained for 10 years or longer was selected from patients attending a periodontal practice. All patients followed a similar treatment: basic procedures, re-evaluation and periodontal surgery where indicated. Reasons for tooth loss were categorized as periodontal, caries, endodontal, root fractures and extraction of retained or partially erupted third molars. Of the 2927 teeth present at the completion of active periodontal treatment, 53 (1.8%) were lost due to periodontal disease, 16 (0.5%) for root fracture, six (0.2%) to caries, five (0.2%) for endodontic reasons and 31 (1.0%) were lost to extraction of retained or partially erupted third molars. Logistic regression analysis was performed to investigate the association between five independent variables with tooth loss due to periodontitis. Only age (> 60 years) and smoking were statistically significant (p < 0.05). The findings of this survey were consistent with previous studies. Older subjects and smokers were more susceptible to periodontal tooth loss. In addition, patients with generalized chronic periodontitis were treated and maintained for long-term periods with low rates of tooth loss.

  20. Supporting the personnel reliability decision-making process with artificial intelligence

    International Nuclear Information System (INIS)

    Harte, D.C.

    1991-01-01

    Recent legislation concerning personnel security has vastly increased the responsibility and accountability of the security manager. Access authorization, fitness for duty, and personnel security access programs require decisions regarding an individual's trustworthiness and reliability based on the findings of a background investigation. While these guidelines provide significant data and are useful as a tool, limited resources are available to the adjudicator of derogatory information on what is and is not acceptable in terms of granting access to sensitive areas of nuclear plants. The reason why one individual is deemed unacceptable and the next acceptable may be questioned and cause discriminatory accusations. This paper is continuation of discussion on workforce reliability, focusing on the use of artificial intelligence to support the decisions of a security manager. With this support, the benefit of previous decisions helps ensure consistent adjudication of background investigations

  1. Assessing the potential for using wetlands as intermediary storages to conjunctively maintain ecological values and support agricultural demands.

    Science.gov (United States)

    Ning, Nathan S P; Watkins, Susanne C; Gawne, Ben; Nielsen, Daryl L

    2012-09-30

    Water sharing to meet both agricultural and environmental demands is a critical issue affecting the health of many floodplain river systems around the world. This study explored the potential for using wetlands as temporary off-river storages to conjunctively maintain ecological values and support agricultural demands by assessing the effects of artificial drawdown on wetland aquatic plant communities. An initial experiment was undertaken in outdoor mesocosms in which four different treatments were compared over a 131 day duration: (1) natural drawdown where the water was left to drawdown naturally via evaporation; (2) partial drawdown where approximately half of the volume of water was pumped out after 42 days; (3) stepped drawdown where approximately half of the volume of water pumped out after 42 days, and then the remaining volume of water was pumped out after 117 days; and (4) total drawdown where all of the of water was pumped out after 117 days. A complementary field study was subsequently undertaken where two wetlands were left to drawdown naturally and two were partially drawn down artificially (i.e. had approximately half of their volume removed by pumping). Results from both of these studies indicated that neither aquatic plant abundance nor taxon richness were adversely affected by partial drawdown. Rather, both studies showed that aquatic plant communities subjected to a partial drawdown treatment became more species rich and diverse than communities subjected to a natural drawdown treatment. This suggests that it may be possible to use wetlands as intermediary storages for the dual purposes of maintaining ecological values and supporting agricultural demands. Crown Copyright © 2012. Published by Elsevier Ltd. All rights reserved.

  2. A support vector density-based importance sampling for reliability assessment

    International Nuclear Information System (INIS)

    Dai, Hongzhe; Zhang, Hao; Wang, Wei

    2012-01-01

    An importance sampling method based on the adaptive Markov chain simulation and support vector density estimation is developed in this paper for efficient structural reliability assessment. The methodology involves the generation of samples that can adaptively populate the important region by the adaptive Metropolis algorithm, and the construction of importance sampling density by support vector density. The use of the adaptive Metropolis algorithm may effectively improve the convergence and stability of the classical Markov chain simulation. The support vector density can approximate the sampling density with fewer samples in comparison to the conventional kernel density estimation. The proposed importance sampling method can effectively reduce the number of structural analysis required for achieving a given accuracy. Examples involving both numerical and practical structural problems are given to illustrate the application and efficiency of the proposed methodology.

  3. User`s manual of a support system for human reliability analysis

    Energy Technology Data Exchange (ETDEWEB)

    Yokobayashi, Masao [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment; Tamura, Kazuo

    1995-10-01

    Many kinds of human reliability analysis (HRA) methods have been developed. However, users are required to be skillful so as to use them, and also required complicated works such as drawing event tree (ET) and calculation of uncertainty bounds. Moreover, each method is not so complete that only one method of them is not enough to evaluate human reliability. Therefore, a personal computer (PC) based support system for HRA has been developed to execute HRA practically and efficiently. The system consists of two methods, namely, simple method and detailed one. The former uses ASEP that is a simplified THERP-technique, and combined method of OAT and HRA-ET/DeBDA is used for the latter. Users can select a suitable method for their purpose. Human error probability (HEP) data were collected and a database of them was built to use for the support system. This paper describes outline of the HRA methods, support functions and user`s guide of the system. (author).

  4. Reliability of Wind Speed Data from Satellite Altimeter to Support Wind Turbine Energy

    Science.gov (United States)

    Uti, M. N.; Din, A. H. M.; Omar, A. H.

    2017-10-01

    Satellite altimeter has proven itself to be one of the important tool to provide good quality information in oceanographic study. Nowadays, most countries in the world have begun in implementation the wind energy as one of their renewable energy for electric power generation. Many wind speed studies conducted in Malaysia using conventional method and scientific technique such as anemometer and volunteer observing ships (VOS) in order to obtain the wind speed data to support the development of renewable energy. However, there are some limitations regarding to this conventional method such as less coverage for both spatial and temporal and less continuity in data sharing by VOS members. Thus, the aim of this research is to determine the reliability of wind speed data by using multi-mission satellite altimeter to support wind energy potential in Malaysia seas. Therefore, the wind speed data are derived from nine types of satellite altimeter starting from year 1993 until 2016. Then, to validate the reliability of wind speed data from satellite altimeter, a comparison of wind speed data form ground-truth buoy that located at Sabah and Sarawak is conducted. The validation is carried out in terms of the correlation, the root mean square error (RMSE) calculation and satellite track analysis. As a result, both techniques showing a good correlation with value positive 0.7976 and 0.6148 for point located at Sabah and Sarawak Sea, respectively. It can be concluded that a step towards the reliability of wind speed data by using multi-mission satellite altimeter can be achieved to support renewable energy.

  5. [The analytical reliability of clinical laboratory information and role of the standards in its support].

    Science.gov (United States)

    Men'shikov, V V

    2012-12-01

    The article deals with the factors impacting the reliability of clinical laboratory information. The differences of qualities of laboratory analysis tools produced by various manufacturers are discussed. These characteristics are the causes of discrepancy of the results of laboratory analyses of the same analite. The role of the reference system in supporting the comparability of laboratory analysis results is demonstrated. The project of national standard is presented to regulate the requirements to standards and calibrators for analysis of qualitative and non-metrical characteristics of components of biomaterials.

  6. Reliability and Validity of the Multidimensional Scale of Perceived Social Support (MSPSS): Thai Version.

    Science.gov (United States)

    Wongpakaran, Tinakon; Wongpakaran, Nahathai; Ruktrakul, Ruk

    2011-01-01

    This study examines the Thai version of the Multidimensional Scale of Perceived Social Support (MSPSS) for its psychometric properties. In total 462 participants were recruited - 310 medical students from Chiang Mai University and 152 psychiatric patients, and they completed the Thai version of the MSPSS, the State Trait Anxiety Inventory (STAI), the Rosenberg Self-Esteem Scale (RSES) and the Thai Depression Inventory (TDI). Test-retest reliability was conducted over a four week period. Factor analysis produced three-factor solutions for both patient (PG) and student groups (SG), and overall the model demonstrated adequate fit indices. The mean total score and the sub-scale score for the SG were statistically higher than those in the PG, except for 'Significant Others'. The internal consistency of the scale was good, with a Cronbach's alpha of 0.91 for the SG and 0.87 for the PG. After a four week retest for reliability exercise, the intra-class correlation coefficient (ICC) was found to be 0.84. The Thai-MSPSS was found to have a negative correlation with the STAI and the TDI, but was positively correlated with the RSES. The Thai MSPSS is a reliable and valid instrument to use.

  7. A fast method for calculating reliable event supports in tree reconciliations via Pareto optimality.

    Science.gov (United States)

    To, Thu-Hien; Jacox, Edwin; Ranwez, Vincent; Scornavacca, Celine

    2015-11-14

    Given a gene and a species tree, reconciliation methods attempt to retrieve the macro-evolutionary events that best explain the discrepancies between the two tree topologies. The DTL parsimonious approach searches for a most parsimonious reconciliation between a gene tree and a (dated) species tree, considering four possible macro-evolutionary events (speciation, duplication, transfer, and loss) with specific costs. Unfortunately, many events are erroneously predicted due to errors in the input trees, inappropriate input cost values or because of the existence of several equally parsimonious scenarios. It is thus crucial to provide a measure of the reliability for predicted events. It has been recently proposed that the reliability of an event can be estimated via its frequency in the set of most parsimonious reconciliations obtained using a variety of reasonable input cost vectors. To compute such a support, a straightforward but time-consuming approach is to generate the costs slightly departing from the original ones, independently compute the set of all most parsimonious reconciliations for each vector, and combine these sets a posteriori. Another proposed approach uses Pareto-optimality to partition cost values into regions which induce reconciliations with the same number of DTL events. The support of an event is then defined as its frequency in the set of regions. However, often, the number of regions is not large enough to provide reliable supports. We present here a method to compute efficiently event supports via a polynomial-sized graph, which can represent all reconciliations for several different costs. Moreover, two methods are proposed to take into account alternative input costs: either explicitly providing an input cost range or allowing a tolerance for the over cost of a reconciliation. Our methods are faster than the region based method, substantially faster than the sampling-costs approach, and have a higher event-prediction accuracy on

  8. Individual selection of X-ray tube settings in computed tomography coronary angiography: Reliability of an automated software algorithm to maintain constant image quality.

    Science.gov (United States)

    Durmus, Tahir; Luhur, Reny; Daqqaq, Tareef; Schwenke, Carsten; Knobloch, Gesine; Huppertz, Alexander; Hamm, Bernd; Lembcke, Alexander

    2016-05-01

    To evaluate a software tool that claims to maintain a constant contrast-to-noise ratio (CNR) in high-pitch dual-source computed tomography coronary angiography (CTCA) by automatically selecting both X-ray tube voltage and current. A total of 302 patients (171 males; age 61±12years; body weight 82±17kg, body mass index 27.3±4.6kg/cm(2)) underwent CTCA with a topogram-based, automatic selection of both tube voltage and current using dedicated software with quality reference values of 100kV and 250mAs/rotation (i.e., standard values for an average adult weighing 75kg) and an injected iodine load of 222mg/kg. The average radiation dose was estimated to be 1.02±0.64mSv. All data sets had adequate contrast enhancement. Average CNR in the aortic root, left ventricle, and left and right coronary artery was 15.7±4.5, 8.3±2.9, 16.1±4.3 and 15.3±3.9 respectively. Individual CNR values were independent of patients' body size and radiation dose. However, individual CNR values may vary considerably between subjects as reflected by interquartile ranges of 12.6-18.6, 6.2-9.9, 12.8-18.9 and 12.5-17.9 respectively. Moreover, average CNR values were significantly lower in males than females (15.1±4.1 vs. 16.6±11.7 and 7.9±2.7 vs. 8.9±3.0, 15.5±3.9 vs. 16.9±4.6 and 14.7±3.6 vs. 16.0±4.1 respectively). A topogram-based automatic selection of X-ray tube settings in CTCA provides diagnostic image quality independent of patients' body size. Nevertheless, considerable variation of individual CNR values between patients and significant differences of CNR values between males and females occur which questions the reliability of this approach. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  9. Reliability and validity of DS-ADHD: A decision support system on attention deficit hyperactivity disorders.

    Science.gov (United States)

    Chu, Kuo-Chung; Huang, Yu-Shu; Tseng, Chien-Fu; Huang, Hsin-Jou; Wang, Chih-Huan; Tai, Hsin-Yi

    2017-03-01

    The purpose of this study is to examine the reliability of the clinical use of the self-built decision support system, diagnosis-supported attention deficit hyperactivity disorder (DS-ADHD), in an effort to develop the DS-ADHD system, by probing into the development of indicating patterns of past screening support systems for ADHD. The study collected data based on 107 subjects, who were divided into two groups, non-ADHD and ADHD, based on the doctor's determination, using the DSM-IV diagnostic standards. The two groups then underwent Test of Variables of Attention (TOVA) and DS-ADHD testing. The survey and testing results underwent one-way ANOVA and split-half method statistical analysis, in order to further understand whether there were any differences between the DS-ADHD and the identification tools used in today's clinical trials. The results of the study are as follows: 1) The ROC area between the TOVA and the clinical identification rate is 0.787 (95% confidence interval: 0.701-0.872); 2) The ROC area between the DS-ADHD and the clinical identification rate is 0.867 (95% confidence interval: 0.801-0.933). The study results show that DS-ADHD has the characteristics of screening for ADHD, based on its reliability and validity. It does not display any statistical differences when compared with TOVA systems that are currently on the market. However, the system is more effective and the accuracy rate is better than TOVA. It is a good tool to screen ADHD not only in Chinese children, but also in western country. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  10. 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.

  11. 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 ...

  12. A dynamic particle filter-support vector regression method for reliability prediction

    International Nuclear Information System (INIS)

    Wei, Zhao; Tao, Tao; ZhuoShu, Ding; Zio, Enrico

    2013-01-01

    Support vector regression (SVR) has been applied to time series prediction and some works have demonstrated the feasibility of its use to forecast system reliability. For accuracy of reliability forecasting, the selection of SVR's parameters is important. The existing research works on SVR's parameters selection divide the example dataset into training and test subsets, and tune the parameters on the training data. However, these fixed parameters can lead to poor prediction capabilities if the data of the test subset differ significantly from those of training. Differently, the novel method proposed in this paper uses particle filtering to estimate the SVR model parameters according to the whole measurement sequence up to the last observation instance. By treating the SVR training model as the observation equation of a particle filter, our method allows updating the SVR model parameters dynamically when a new observation comes. Because of the adaptability of the parameters to dynamic data pattern, the new PF–SVR method has superior prediction performance over that of standard SVR. Four application results show that PF–SVR is more robust than SVR to the decrease of the number of training data and the change of initial SVR parameter values. Also, even if there are trends in the test data different from those in the training data, the method can capture the changes, correct the SVR parameters and obtain good predictions. -- Highlights: •A dynamic PF–SVR method is proposed to predict the system reliability. •The method can adjust the SVR parameters according to the change of data. •The method is robust to the size of training data and initial parameter values. •Some cases based on both artificial and real data are studied. •PF–SVR shows superior prediction performance over standard SVR

  13. Reliability Analysis of RSG-GAS Primary Cooling System to Support Aging Management Program

    Science.gov (United States)

    Deswandri; Subekti, M.; Sunaryo, Geni Rina

    2018-02-01

    Multipurpose Research Reactor G.A. Siwabessy (RSG-GAS) which has been operating since 1987 is one of the main facilities on supporting research, development and application of nuclear energy programs in BATAN. Until now, the RSG-GAS research reactor has been successfully operated safely and securely. However, because it has been operating for nearly 30 years, the structures, systems and components (SSCs) from the reactor would have started experiencing an aging phase. The process of aging certainly causes a decrease in reliability and safe performances of the reactor, therefore the aging management program is needed to resolve the issues. One of the programs in the aging management is to evaluate the safety and reliability of the system and also screening the critical components to be managed.One method that can be used for such purposes is the Fault Tree Analysis (FTA). In this papers FTA method is used to screening the critical components in the RSG-GAS Primary Cooling System. The evaluation results showed that the primary isolation valves are the basic events which are dominant against the system failure.

  14. Effect of Diamondlike Carbon Coating on Reliability of Implant-Supported Crowns.

    Science.gov (United States)

    Hirata, Ronaldo; Machado, Lucas Silveira; Bonfante, Estevam A; Yamaguchi, Satoshi; Imazato, Satoshi; Coelho, Paulo G

    2015-01-01

    To evaluate the effect of diamondlike carbon (DLC) coating on abutments and/or abutment screws on the reliability, characteristic strength, and Weibull modulus of implant-supported single crowns. Seventy-two external hexagon implants (Emfills Implant 4 mm diameter, 10 mm length, Emfills) were divided into four groups (n = 18 each), according to the presence or not of a DLC coating in the abutment and/or abutment screw, as follows: abutment without coating, screw without coating (AwcSwc); abutment without coating with coated screw (AwcSC); abutment coated with noncoated screw (ACSwc), and coated abutment with coated screw (ACSC). Abutments and screws were evaluated with scanning electron microscopy. The specimens were subjected to step-stress accelerated life testing in water. Use-level probability Weibull curves and reliability for a mission of 100,000 cycles at 150 N (90% two-sided confidence intervals) were calculated. Polarized light and scanning electron microscopes were used for fractographic analysis. For a mission of 100,000 cycles at 150 N, reliability was 0.45 (0.20 to 0.67), 0.12 (0.00 to 0.47), 0.56 (0.17 to 0.82), and 0.44 (0.07 to 0.77) for AwcSwc, AwcSC, ACSwc, and ACSC, respectively. The probability Weibull calculation showed a Weibull modulus (m) of m = 5.50, m = 11.64, m = 16.96, and m = 15.08 and the characteristic strengths (η, which indicates the load at which 63.2% of the specimens of each group fail) of η = 202.67 N, ŋ = 206.64 N, ŋ = 192.54 N, and ŋ = 203.59 N for AwcSwc, AwcSC, ACSwc, and ACSC, respectively. Abutment screw fracture was the chief failure outcome in all groups. Characteristic strength values were not different among groups; neither was reliability. However, an increase in Weibull modulus (indicating low variability of the results) was observed with DLC coating of abutment or screw or both.

  15. Sustainable Energy Solutions Task 2.0: Wind Turbine Reliability and Maintainability Enhancement through System-wide Structure Health Monitoring and Modifications to Rotating Components

    Energy Technology Data Exchange (ETDEWEB)

    Twomey, Janet M. [Wichita State Univ., Wichita, KS (United States)

    2010-04-30

    An evaluation of nondestructive structural health monitoring methods was completed with over 132 documents, 37 specifically about wind turbines, summarized into a technology matrix. This matrix lists the technology, what can be monitored with this technology, and gives a short summary of the key aspects of the technology and its application. Passive and active acoustic emission equipment from Physical Acoustics Corp. and Acellent Technologies have been evaluated and selected for use in experimental state loading and fatigue tests of composite wind turbine blade materials. Acoustic Emission (AE) and Active Ultrasonic Testing (AUT), were applied to composite coupons with both simulated and actual damage. The results found that, while composites are more complicated in nature, compared to metallic structures, an artificial neural network analysis could still be used to determine damage. For the AE system, the failure mode could be determined (i.e. fiber breakage, delamination, etc.). The Acellent system has been evaluated to work well with composite materials. A test-rig for reliability testing of the rotating components was constructed. The research on the types of bearings used in the wind turbines indicated that in most of the designs, the main bearings utilized to support the shaft are cylindrical roller bearings. The accelerated degradation testing of a population of bearings was performed. Vibration and acoustic emission data was collected and analyzed in order to identify a representative degradation signal for each bearing to identify the initiation of the degradation process in the bearings. Afterwards, the RMS of the vibration signal from degradation initiation up to the end of the useful life of the bearing was selected to predict the remaining useful life of the bearing. This step included fitting Autoregressive Moving Average (ARMA) models to the degradation signals and approximating the probability distribution function (PDF) of remaining useful life

  16. QA support for TFTR reliability improvement program in preparation for DT operation

    International Nuclear Information System (INIS)

    Parsells, R.F.; Howard, H.P.

    1987-01-01

    As TFTR approaches experiments in the Q=1 regime, machine reliability becomes a major variable in achieving experimental objectives. This paper describes the methods used to quantify current reliability levels, levels required for D-T operations, proposed methods for reliability growth and improvement, and tracking of reliability performance in that growth. Included in this scope are data collection techniques and short comings, bounding current reliability on the upper end, and requirements for D-T operations. Problem characterization through Pareto diagrams provides insight into recurrent failure modes and the use of Duane plots for charting of reliability changes both cumulative and instantaneous, is explained and demonstrated

  17. Reliable Fault Classification of Induction Motors Using Texture Feature Extraction and a Multiclass Support Vector Machine

    Directory of Open Access Journals (Sweden)

    Jia Uddin

    2014-01-01

    Full Text Available This paper proposes a method for the reliable fault detection and classification of induction motors using two-dimensional (2D texture features and a multiclass support vector machine (MCSVM. The proposed model first converts time-domain vibration signals to 2D gray images, resulting in texture patterns (or repetitive patterns, and extracts these texture features by generating the dominant neighborhood structure (DNS map. The principal component analysis (PCA is then used for the purpose of dimensionality reduction of the high-dimensional feature vector including the extracted texture features due to the fact that the high-dimensional feature vector can degrade classification performance, and this paper configures an effective feature vector including discriminative fault features for diagnosis. Finally, the proposed approach utilizes the one-against-all (OAA multiclass support vector machines (MCSVMs to identify induction motor failures. In this study, the Gaussian radial basis function kernel cooperates with OAA MCSVMs to deal with nonlinear fault features. Experimental results demonstrate that the proposed approach outperforms three state-of-the-art fault diagnosis algorithms in terms of fault classification accuracy, yielding an average classification accuracy of 100% even in noisy environments.

  18. Human Reliability Analysis in Support of Risk Assessment for Positive Train Control

    Science.gov (United States)

    2003-06-01

    This report describes an approach to evaluating the reliability of human actions that are modeled in a probabilistic risk assessment : (PRA) of train control operations. This approach to human reliability analysis (HRA) has been applied in the case o...

  19. Reliability of a Novel Social Activity Questionnaire: Perceived Social Support and Verbal Interaction in the Wisconsin Registry for Alzheimer's Prevention.

    Science.gov (United States)

    Zuelsdorff, Megan L; Koscik, Rebecca L; Okonkwo, Ozioma C; Peppard, Paul E; Hermann, Bruce P; Sager, Mark A; Johnson, Sterling C; Engelman, Corinne D

    2018-02-01

    Social activity is associated with healthy aging and preserved cognition. Such activity includes a confluence of social support and verbal interaction, each influencing cognition through rarely parsed, mechanistically distinct pathways. We created a novel verbal interaction measure for the Wisconsin Registry for Alzheimer's Prevention (WRAP) and assessed reliability of resultant data, a first step toward mechanism-driven examination of social activity as a modifiable predictor of cognitive health. Two WRAP subsamples completed a test-retest study to determine 8-week stability ( n = 107) and 2-year stability ( n = 136) of verbal interaction, and 2-year stability of perceived social support. Reliability was determined using quadratic-weighted kappa, percent agreement, or correlation coefficients. Reliability was fair to almost perfect. The association between social support and interaction quantity decreased with age. Social activity data demonstrate moderate to excellent temporal stability. Moreover, in older individuals, social support and verbal interaction represent two distinct dimensions of social activity.

  20. Perceived Benefits and Factors that Influence the Ability to Establish and Maintain Patient Support Groups in Rare Diseases: A Scoping Review.

    Science.gov (United States)

    Delisle, Vanessa C; Gumuchian, Stephanie T; Rice, Danielle B; Levis, Alexander W; Kloda, Lorie A; Körner, Annett; Thombs, Brett D

    2017-06-01

    Support groups are an important resource for many people living with rare diseases. The perceived benefits of participating in support groups for people with rare diseases and factors that may influence the ability to successfully establish and maintain these groups are not well understood. Thus, the objective of this scoping review was to provide a mapping of the available evidence on the (1) benefits or perceived benefits of participating in rare disease support groups and (2) barriers and facilitators of establishing and maintaining these groups. CINAHL and PubMed were searched from January 2000 to August 2015, with no language restrictions. Publications that described the benefits or perceived benefits of participating in rare disease support groups or the barriers and facilitators of establishing and maintaining them were eligible for inclusion. Two investigators independently evaluated titles/abstracts and full-text publications for eligibility, and extracted data from each included publication. Ten publications were included in the scoping review. There was no trial evidence on support group benefits. All ten publications reported on the perceived benefits of participating in rare disease support groups. Three reported on barriers and facilitators of establishing and maintaining them. Overall, seven different perceived benefits of participating in rare disease support groups were identified: (1) meeting and befriending other people with the same rare disease and similar experiences; (2) learning about the disease and related treatments; (3) giving and receiving emotional support; (4) having a place to speak openly about the disease and one's feelings; (5) learning coping skills; (6) feeling empowered and hopeful; and (7) advocating to improve healthcare for other rare disease patients. Several facilitators (e.g., meeting via teleconference) and barriers (e.g., getting patients and/or family members to lead the group) of establishing and maintaining these

  1. Wnt signaling maintains the notochord fate for progenitor cells and supports the posterior extension of the notochord

    OpenAIRE

    Ukita, Kanako; Hirahara, Shino; Oshima, Naoko; Imuta, Yu; Yoshimoto, Aki; Jang, Chuan-Wei; Oginuma, Masayuki; Saga, Yumiko; Behringer, Richard R.; Kondoh, Hisato; Sasaki, Hiroshi

    2009-01-01

    The notochord develops from notochord progenitor cells (NPCs) and functions as a major signaling center to regulate trunk and tail development. NPCs are initially specified in the node by Wnt and Nodal signals at the gastrula stage. However, the underlying mechanism that maintains the NPCs throughout embryogenesis to contribute to the posterior extension of the notochord remains unclear. Here, we demonstrate that Wnt signaling in the NPCs is essential for posterior extension of the notochord....

  2. Development of KSC program for investigating and generating field failure rates. Reliability handbook for ground support equipment

    Science.gov (United States)

    Bloomquist, C. E.; Kallmeyer, R. H.

    1972-01-01

    Field failure rates and confidence factors are presented for 88 identifiable components of the ground support equipment at the John F. Kennedy Space Center. For most of these, supplementary information regarding failure mode and cause is tabulated. Complete reliability assessments are included for three systems, eight subsystems, and nine generic piece-part classifications. Procedures for updating or augmenting the reliability results are also included.

  3. Seismic reliability assessment of RC structures including soil–structure interaction using wavelet weighted least squares support vector machine

    International Nuclear Information System (INIS)

    Khatibinia, Mohsen; Javad Fadaee, Mohammad; Salajegheh, Javad; Salajegheh, Eysa

    2013-01-01

    An efficient metamodeling framework in conjunction with the Monte-Carlo Simulation (MCS) is introduced to reduce the computational cost in seismic reliability assessment of existing RC structures. In order to achieve this purpose, the metamodel is designed by combining weighted least squares support vector machine (WLS-SVM) and a wavelet kernel function, called wavelet weighted least squares support vector machine (WWLS-SVM). In this study, the seismic reliability assessment of existing RC structures with consideration of soil–structure interaction (SSI) effects is investigated in accordance with Performance-Based Design (PBD). This study aims to incorporate the acceptable performance levels of PBD into reliability theory for comparing the obtained annual probability of non-performance with the target values for each performance level. The MCS method as the most reliable method is utilized to estimate the annual probability of failure associated with a given performance level in this study. In WWLS-SVM-based MCS, the structural seismic responses are accurately predicted by WWLS-SVM for reducing the computational cost. To show the efficiency and robustness of the proposed metamodel, two RC structures are studied. Numerical results demonstrate the efficiency and computational advantages of the proposed metamodel for the seismic reliability assessment of structures. Furthermore, the consideration of the SSI effects in the seismic reliability assessment of existing RC structures is compared to the fixed base model. It shows which SSI has the significant influence on the seismic reliability assessment of structures.

  4. 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.

  5. Bridging Human Reliability Analysis and Psychology, Part 2: A Cognitive Framework to Support HRA

    Energy Technology Data Exchange (ETDEWEB)

    April M. Whaley; Stacey M. L. Hendrickson; Ronald L. Boring; Jing Xing

    2012-06-01

    This is the second of two papers that discuss the literature review conducted as part of the U.S. Nuclear Regulatory Commission (NRC) effort to develop a hybrid human reliability analysis (HRA) method in response to Staff Requirements Memorandum (SRM) SRM-M061020. This review was conducted with the goal of strengthening the technical basis within psychology, cognitive science and human factors for the hybrid HRA method being proposed. An overview of the literature review approach and high-level structure is provided in the first paper, whereas this paper presents the results of the review. The psychological literature review encompassed research spanning the entirety of human cognition and performance, and consequently produced an extensive list of psychological processes, mechanisms, and factors that contribute to human performance. To make sense of this large amount of information, the results of the literature review were organized into a cognitive framework that identifies causes of failure of macrocognition in humans, and connects those proximate causes to psychological mechanisms and performance influencing factors (PIFs) that can lead to the failure. This cognitive framework can serve as a tool to inform HRA. Beyond this, however, the cognitive framework has the potential to also support addressing human performance issues identified in Human Factors applications.

  6. Wnt signaling maintains the notochord fate for progenitor cells and supports the posterior extension of the notochord.

    Science.gov (United States)

    Ukita, Kanako; Hirahara, Shino; Oshima, Naoko; Imuta, Yu; Yoshimoto, Aki; Jang, Chuan-Wei; Oginuma, Masayuki; Saga, Yumiko; Behringer, Richard R; Kondoh, Hisato; Sasaki, Hiroshi

    2009-10-01

    The notochord develops from notochord progenitor cells (NPCs) and functions as a major signaling center to regulate trunk and tail development. NPCs are initially specified in the node by Wnt and Nodal signals at the gastrula stage. However, the underlying mechanism that maintains the NPCs throughout embryogenesis to contribute to the posterior extension of the notochord remains unclear. Here, we demonstrate that Wnt signaling in the NPCs is essential for posterior extension of the notochord. Genetic labeling revealed that the Noto-expressing cells in the ventral node contribute the NPCs that reside in the tail bud. Robust Wnt signaling in the NPCs was observed during posterior notochord extension. Genetic attenuation of the Wnt signal via notochord-specific beta-catenin gene ablation resulted in posterior truncation of the notochord. In the NPCs of such mutant embryos, the expression of notochord-specific genes was down-regulated, and an endodermal marker, E-cadherin, was observed. No significant alteration of cell proliferation or apoptosis of the NPCs was detected. Taken together, our data indicate that the NPCs are derived from Noto-positive node cells, and are not fully committed to a notochordal fate. Sustained Wnt signaling is required to maintain the NPCs' notochordal fate.

  7. Maintainability allocation

    International Nuclear Information System (INIS)

    Guyot, Christian.

    1980-06-01

    The author gives the general lines of a method for the allocation and for the evaluation of maintainability of complex systems which is to be developed during the conference. The maintainability objective is supposed to be formulated under the form of a mean time to repair (M.T.T.R.) [fr

  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. 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

  10. Validity and reliability of questionnaires measuring physical activity self-efficacy, enjoyment, social support among Hong Kong Chinese children

    Science.gov (United States)

    Physical activity (PA) correlates have not been extensively studied in Hong Kong children. The aim of this study is to assess the validity and reliability of translated scales to measure PA related self-efficacy, enjoyment and social support in Hong Kong Chinese children. Sample 1 (n=273, aged 8–12 ...

  11. Root cause analysis in support of reliability enhancement of engineering components

    International Nuclear Information System (INIS)

    Kumar, Sachin; Mishra, Vivek; Joshi, N.S.; Varde, P.V.

    2014-01-01

    Reliability based methods have been widely used for the safety assessment of plant system, structures and components. These methods provide a quantitative estimation of system reliability but do not give insight into the failure mechanism. Understanding the failure mechanism is a must to avoid the recurrence of the events and enhancement of the system reliability. Root cause analysis provides a tool for gaining detailed insights into the causes of failure of component with particular attention to the identification of fault in component design, operation, surveillance, maintenance, training, procedures and policies which must be improved to prevent repetition of incidents. Root cause analysis also helps in developing Probabilistic Safety Analysis models. A probabilistic precursor study provides a complement to the root cause analysis approach in event analysis by focusing on how an event might have developed adversely. This paper discusses the root cause analysis methodologies and their application in the specific case studies for enhancement of system reliability. (author)

  12. Reliable Autonomous Surface Mobility (RASM) in Support of Human Exploration, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — ProtoInnovations, LLC and Carnegie Mellon University have formed a partnership to commercially develop rover-autonomy technologies into Reliable Autonomous Surface...

  13. A novel ontology approach to support design for reliability considering environmental effects.

    Science.gov (United States)

    Sun, Bo; Li, Yu; Ye, Tianyuan; Ren, Yi

    2015-01-01

    Environmental effects are not considered sufficiently in product design. Reliability problems caused by environmental effects are very prominent. This paper proposes a method to apply ontology approach in product design. During product reliability design and analysis, environmental effects knowledge reusing is achieved. First, the relationship of environmental effects and product reliability is analyzed. Then environmental effects ontology to describe environmental effects domain knowledge is designed. Related concepts of environmental effects are formally defined by using the ontology approach. This model can be applied to arrange environmental effects knowledge in different environments. Finally, rubber seals used in the subhumid acid rain environment are taken as an example to illustrate ontological model application on reliability design and analysis.

  14. Effectiveness of different approaches to disseminating traveler information on travel time reliability. [supporting datasets

    Science.gov (United States)

    2013-11-30

    Travel time reliability information includes static data about traffic speeds or trip times that capture historic variations from day to day, and it can help individuals understand the level of variation in traffic. Unlike real-time travel time infor...

  15. Some Aspects of Psychophysiological Support of Crew Member's Performance Reliability in Space Flight

    Science.gov (United States)

    Nechaev, A. P.; Myasnikov, V. I.; Stepanova, S. I.; Isaev, G. F.; Bronnikov, S. V.

    The history of cosmonautics demonstrates many instances in which only crewmembers' intervention allowed critical situations to be resolved, or catastrophes to be prevented. However, during "crew-spacecraft" system operation human is exposed by influence of numerous flight factors, and beforehand it is very difficult to predict their effects on his functional state and work capacity. So, the incidents are known when unfavorable alterations of crewmember's psychophysiological state (PPS) provoked errors in task performance. The objective of the present investigation was to substantiate the methodological approach directed to increase reliability of a crewmember performance (human error prevention) by means of management of his/her PPS. The specific aims of the investigation were: 1) to evaluate the statistical significance of the interrelation between crew errors (CE) and crewmember's PPS, and 2) to develop the way of PPS management. At present, there is no conventional method to assess combined effect of flight conditions (microgravity, confinement, psychosocial factors, etc.) on crewmembers' PPS. For this purpose experts of the Medical Support Group (psychoneurologists and psychologists) at the Moscow Mission Control Center analyze information received during radio and TV contacts with crew. Peculiarities of behavior, motor activity, sleep, speech, mood, emotional reactions, well-being and sensory sphere, trend of dominant interests and volitional acts, signs of deprivation phenomena are considered as separate indicators of crewmember's PPS. The set of qualitative symptoms reflecting PPS alterations and corresponding to them ratings (in arbitrary units) was empirically stated for each indicator. It is important to emphasize that symptoms characterizing more powerful PPS alterations have higher ratings. Quantitative value of PPS integral parameter is calculating by adding up the ratings of all separate indicators over a day, a week, or other temporal interval (in

  16. Evaluation of research reactor fuel reliability in support of regulatory requirements

    International Nuclear Information System (INIS)

    Sokolov, Eugene N.

    2005-01-01

    This standards, codes and practices survey is devoted to the problem of reliability of R and D especially research reactor fuel (RRF) performance-related processes. Regulatory R and D evaluations were based on one standard and just few of them provide correlation to other relative standards whereas synthetic process approach reflects actual status of particular R and D practices. Fuel performance regulatory parameters are based on quality standards. A reliability process-based method similar to PSA/FMEA is proposed to evaluate RRF performance- related parameters in terms of reactor safety. (author)

  17. Evaluation of research reactor fuel reliability in support of regulatory requirements

    Energy Technology Data Exchange (ETDEWEB)

    Sokolov, Eugene N [Chalk River Laboratories, AECL, Chalk River, ON, K0J 1J0 (Canada)

    2005-07-01

    This standards, codes and practices survey is devoted to the problem of reliability of R and D especially research reactor fuel (RRF) performance-related processes. Regulatory R and D evaluations were based on one standard and just few of them provide correlation to other relative standards whereas synthetic process approach reflects actual status of particular R and D practices. Fuel performance regulatory parameters are based on quality standards. A reliability process-based method similar to PSA/FMEA is proposed to evaluate RRF performance- related parameters in terms of reactor safety. (author)

  18. Assessing Reliability of Cellulose Hydrolysis Models to Support Biofuel Process Design – Identifiability and Uncertainty Analysis

    DEFF Research Database (Denmark)

    Sin, Gürkan; Meyer, Anne S.; Gernaey, Krist

    2010-01-01

    The reliability of cellulose hydrolysis models is studied using the NREL model. An identifiability analysis revealed that only 6 out of 26 parameters are identifiable from the available data (typical hydrolysis experiments). Attempting to identify a higher number of parameters (as done in the ori......The reliability of cellulose hydrolysis models is studied using the NREL model. An identifiability analysis revealed that only 6 out of 26 parameters are identifiable from the available data (typical hydrolysis experiments). Attempting to identify a higher number of parameters (as done...

  19. Non-Parametric Bayesian Updating within the Assessment of Reliability for Offshore Wind Turbine Support Structures

    DEFF Research Database (Denmark)

    Ramirez, José Rangel; Sørensen, John Dalsgaard

    2011-01-01

    This work illustrates the updating and incorporation of information in the assessment of fatigue reliability for offshore wind turbine. The new information, coming from external and condition monitoring can be used to direct updating of the stochastic variables through a non-parametric Bayesian u...

  20. A feasible, aesthetic quality evaluation of implant-supported single crowns: an analysis of validity and reliability

    DEFF Research Database (Denmark)

    Hosseini, Mandana; Gotfredsen, Klaus

    2012-01-01

    OBJECTIVES: To test the reliability and validity of six aesthetic parameters and to compare the professional- and patient-reported aesthetic outcomes. MATERIAL AND METHODS: Thirty-four patients with 66 implant-supported premolar crowns were included. Two prosthodontists and 11 dental students......,24) were found between patient and professional evaluations. CONCLUSIONS: The feasibility, reliability and validity of the CIS make the parameters useful for quality control of implant-supported restorations. The professional- and patient-reported aesthetic outcomes had no significant correlation....... and the internal consistency were analysed by Cohen's ¿ and Cronbach's a, respectively. The validity of CIS parameters was tested against the corresponding Visual Analogue Scales (VAS) scores. The Spearman correlation coefficients were used. Six aesthetic Oral Health Impact Profile (OHIP) questions were correlated...

  1. Maintaining positive

    OpenAIRE

    Gheorghe Gh. IONESCU; Adina Letitia NEGRUSA

    2004-01-01

    Maintaining positive work-force relationships includes in effective labor-management relations and making appropriate responses to current employee issues. Among the major current employee issues are protection from arbitrary dismissal, drug and alcohol abuse, privacy rights and family maters and they impact work. In our paper we discus two problems: first, the meanings of industrial democracy; second, the three principal operational concepts of industrial democracy (1) industrial democracy t...

  2. Validity, reliability and support for implementation of independence-scaled procedural assessment in laparoscopic surgery.

    Science.gov (United States)

    Kramp, Kelvin H; van Det, Marc J; Veeger, Nic J G M; Pierie, Jean-Pierre E N

    2016-06-01

    There is no widely used method to evaluate procedure-specific laparoscopic skills. The first aim of this study was to develop a procedure-based assessment method. The second aim was to compare its validity, reliability and feasibility with currently available global rating scales (GRSs). An independence-scaled procedural assessment was created by linking the procedural key steps of the laparoscopic cholecystectomy to an independence scale. Subtitled and blinded videos of a novice, an intermediate and an almost competent trainee, were evaluated with GRSs (OSATS and GOALS) and the independence-scaled procedural assessment by seven surgeons, three senior trainees and six scrub nurses. Participants received a short introduction to the GRSs and independence-scaled procedural assessment before assessment. The validity was estimated with the Friedman and Wilcoxon test and the reliability with the intra-class correlation coefficient (ICC). A questionnaire was used to evaluate user opinion. Independence-scaled procedural assessment and GRS scores improved significantly with surgical experience (OSATS p = 0.001, GOALS p < 0.001, independence-scaled procedural assessment p < 0.001). The ICCs of the OSATS, GOALS and independence-scaled procedural assessment were 0.78, 0.74 and 0.84, respectively, among surgeons. The ICCs increased when the ratings of scrub nurses were added to those of the surgeons. The independence-scaled procedural assessment was not considered more of an administrative burden than the GRSs (p = 0.692). A procedural assessment created by combining procedural key steps to an independence scale is a valid, reliable and acceptable assessment instrument in surgery. In contrast to the GRSs, the reliability of the independence-scaled procedural assessment exceeded the threshold of 0.8, indicating that it can also be used for summative assessment. It furthermore seems that scrub nurses can assess the operative competence of surgical trainees.

  3. The Needs-Based Assessment of Parental (Guardian) Support: a test of its validity and reliability.

    Science.gov (United States)

    Bolen, Rebecca M; Leah Lamb, J; Gradante, Jennifer

    2002-10-01

    The purpose of this paper is to present a newly developed measure of guardian support, the Needs-Based Assessment of Parental (Guardian) Support (NAPS), an empirical evaluation of that measure, and its comparison with another measure of guardian support. The theoretical model that underlies this measure applies humanistic theory and Maslow's hierarchy of needs to the understanding of guardian support. The study employed a cross-sectional nonexperimental survey design using 183 nonoffending guardians who accompanied children presenting for a medical/forensic examination for sexual abuse. The NAPS and an existing measure of guardian support were administered during the hospital outpatient visit, and basic information concerning the child and abuse situations were gathered. The NAPS had robust psychometric properties and was culturally sensitive. Tests of specific hypotheses supported the construct validity of the measure and a conceptualization of guardian support as hierarchical, with four stages of support. The brevity and ease of administration of the NAPS for both the clinician and guardian suggest that it is a viable assessment tool. The strong support for the NAPS' underlying theoretical model suggests that the nonoffending guardians' available resources need to be considered when assessing guardian support.

  4. Reliability and efficiency upgrades of power systems operation by implementing intelligent electronic devices with synchrophasor measurement technology support

    Directory of Open Access Journals (Sweden)

    Mokeev Alexey

    2017-01-01

    Full Text Available This paper reviews issues of reliability and efficiency upgrades of power systems functions by means of a widespread implementation of intelligent electronic devices (IED in various purposes supporting synchrophasor measurement technology. Thus, such issues as IED’s operational analysis in the conditions of electromagnetic and electromechanical transient processes and synthesis of digital filters that improve static and dynamic responses of these devices play an important role in their development.

  5. Reliability and efficiency upgrades of power systems operation by implementing intelligent electronic devices with synchrophasor measurement technology support

    OpenAIRE

    Mokeev Alexey

    2017-01-01

    This paper reviews issues of reliability and efficiency upgrades of power systems functions by means of a widespread implementation of intelligent electronic devices (IED) in various purposes supporting synchrophasor measurement technology. Thus, such issues as IED’s operational analysis in the conditions of electromagnetic and electromechanical transient processes and synthesis of digital filters that improve static and dynamic responses of these devices play an important role in their devel...

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

    KAUST Repository

    Alanis Lobato, Gregorio

    2015-09-23

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

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

    Directory of Open Access Journals (Sweden)

    Gregorio eAlanis-Lobato

    2015-09-01

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

  8. Availability, reliability and logistic support studies of the RF power system design options for the IFMIF accelerator

    International Nuclear Information System (INIS)

    Bargallo, E.; Giralt, A.; Martinez, G.; Weber, M.; Regidor, D.; Arroyo, J.M.; Abal, J.; Dies, J.; Tapia, C.; De Blas, A.; Mendez, P.; Ibarra, A.; Molla, J.

    2013-01-01

    Highlights: ► Current RF system design based on tetrodes chains is evaluated. ► Alternative solid state power amplifiers RF system design is analyzed. ► Both designs are compared in terms of availability, logistics and cost. ► It is concluded that solid state option presents relevant improvements. -- Abstract: The current design of the radio frequency (RF) power system for the International Fusion Materials Irradiation Facility (IFMIF) is based upon tetrodes technology. Due to the improvement in the solid state amplifiers technology, the possibility of using this option for IFMIF RF system is becoming a very competitive alternative presenting from the beginning several advantages in terms of availability, reliability and logistics. The current design based on RF tetrodes chains leads no room for substantial improvements in terms of availability being the requirement for the RF system hard to achieve. The principal goals of this paper are to use RAMI (Reliability, Availability, Maintainability and Inspectionability) analysis in the solid state amplifier design, and to compare the availability, reliability and logistic performances for both alternatives

  9. Availability, reliability and logistic support studies of the RF power system design options for the IFMIF accelerator

    Energy Technology Data Exchange (ETDEWEB)

    Bargallo, E., E-mail: enric.bargallo-font@upc.edu [Fusion Energy Engineering Laboratory (FEEL), Technical University of Catalonia (UPC) Barcelona-Tech, Barcelona (Spain); Giralt, A.; Martinez, G. [Fusion Energy Engineering Laboratory (FEEL), Technical University of Catalonia (UPC) Barcelona-Tech, Barcelona (Spain); Weber, M.; Regidor, D.; Arroyo, J.M. [Centro de Investigaciones Energéticas, Medioambientales y Tecnológicas, Madrid (Spain); Abal, J.; Dies, J.; Tapia, C.; De Blas, A. [Fusion Energy Engineering Laboratory (FEEL), Technical University of Catalonia (UPC) Barcelona-Tech, Barcelona (Spain); Mendez, P.; Ibarra, A.; Molla, J. [Centro de Investigaciones Energéticas, Medioambientales y Tecnológicas, Madrid (Spain)

    2013-10-15

    Highlights: ► Current RF system design based on tetrodes chains is evaluated. ► Alternative solid state power amplifiers RF system design is analyzed. ► Both designs are compared in terms of availability, logistics and cost. ► It is concluded that solid state option presents relevant improvements. -- Abstract: The current design of the radio frequency (RF) power system for the International Fusion Materials Irradiation Facility (IFMIF) is based upon tetrodes technology. Due to the improvement in the solid state amplifiers technology, the possibility of using this option for IFMIF RF system is becoming a very competitive alternative presenting from the beginning several advantages in terms of availability, reliability and logistics. The current design based on RF tetrodes chains leads no room for substantial improvements in terms of availability being the requirement for the RF system hard to achieve. The principal goals of this paper are to use RAMI (Reliability, Availability, Maintainability and Inspectionability) analysis in the solid state amplifier design, and to compare the availability, reliability and logistic performances for both alternatives.

  10. Validity and reliability of the Malay version multidimensional scale of perceived social support (MSPSS-M) among teachers.

    Science.gov (United States)

    Lee, Soo Cheng; Moy, Foong Ming; Hairi, Noran Naqiah

    2017-01-01

    The multidimensional scale of perceived social support (MSPSS) was developed to measure perceived social support. It has been translated and culturally adapted among natives literate in the Malay language. However, its psychometric properties for teachers who are majority females and married have not been assessed. This was a cross-sectional study conducted among the public secondary school teachers in the central region of Peninsular Malaysia from May to July 2013. A total of 150 and 203 teachers were recruited to perform exploratory factor analysis and confirmatory factor analysis (CFA), respectively. Reliability testing was evaluated on 141 teachers via internal consistency and two-week interval test-retest. The 12-item three-factor structure of MSPSS-M was revised to 8-item two-factor structure. The revised MSPSS-M demonstrated excellent fit in CFA with adequate divergent and convergent validity and good factor loadings (0.80-0.90). The revised MSPSS-M also displayed good internal consistency with Cronbach's alpha of 0.91, 0.93 and 0.92 and good test-retest reliability with intraclass correlation of 0.89, 0.88 and 0.88 in the total scale, family and friends factors, respectively. The revised 8-item MSPSS-M is a reliable and valid tool for assessment of perceived social support among teachers.

  11. The difference is more than floating: factors affecting breast cancer survivors' decisions to join and maintain participation in dragon boat teams and support groups.

    Science.gov (United States)

    McDonough, Meghan H; Patterson, Michelle C; Weisenbach, Beth B; Ullrich-French, Sarah; Sabiston, Catherine M

    2018-03-09

    Peer support can be helpful in rehabilitation from breast cancer, but participation in peer support groups is low. Groups that provide support opportunities in physical activity contexts are an attractive alternative for some survivors. This study examined survivors' reasons for joining and maintaining participation on a dragon boat team, along with perceptions of barriers and attractions to traditional peer support groups. Seventeen breast cancer survivors were interviewed on five occasions over their first two seasons of a newly formed dragon boating team to explore their perceptions of peer support groups and dragon boating. Data were inductively analyzed using thematic analysis. Categories surrounding physical, psychological, social and community features were identified with several themes emerging within each. Advantages of dragon boating included opportunities to get a combination of physical, psychosocial and community benefits; health improvement and behavior change; and obtaining social support without the focus being on cancer. Peer support groups were identified as having advantages for forming relationships and avoiding barriers associated with physical activity. While neither type of program meets all needs, practical considerations are identified for incorporating advantages of both programs to improve participation. Implications for rehabilitation Further understanding of perceptions, and attractions and challenges to taking part in group programs will inform development of accessible programs that target multiple rehabilitation needs. Physical activity can provide a positive, alternative focus that takes the emphasis off of cancer, which is more accessible to some survivors. Physical activity also provides opportunities to build relationships around a common, positive goal, which can be a foundation for providing support for coping with cancer.

  12. Real-Time Reliability Verification for UAV Flight Control System Supporting Airworthiness Certification.

    Science.gov (United States)

    Xu, Haiyang; Wang, Ping

    2016-01-01

    In order to verify the real-time reliability of unmanned aerial vehicle (UAV) flight control system and comply with the airworthiness certification standard, we proposed a model-based integration framework for modeling and verification of time property. Combining with the advantages of MARTE, this framework uses class diagram to create the static model of software system, and utilizes state chart to create the dynamic model. In term of the defined transformation rules, the MARTE model could be transformed to formal integrated model, and the different part of the model could also be verified by using existing formal tools. For the real-time specifications of software system, we also proposed a generating algorithm for temporal logic formula, which could automatically extract real-time property from time-sensitive live sequence chart (TLSC). Finally, we modeled the simplified flight control system of UAV to check its real-time property. The results showed that the framework could be used to create the system model, as well as precisely analyze and verify the real-time reliability of UAV flight control system.

  13. Improving the Reliability of Decision-Support Systems for Nuclear Emergency Management by Leveraging Software Design Diversity

    Directory of Open Access Journals (Sweden)

    Tudor B. Ionescu

    2016-03-01

    Full Text Available This paper introduces a novel method of continuous verification of simulation software used in decision-support systems for nuclear emergency management (DSNE. The proposed approach builds on methods from the field of software reliability engineering, such as N-Version Programming, Recovery Blocks, and Consensus Recovery Blocks. We introduce a new acceptance test for dispersion simulation results and a new voting scheme based on taxonomies of simulation results rather than individual simulation results. The acceptance test and the voter are used in a new scheme, which extends the Consensus Recovery Block method by a database of result taxonomies to support machine-learning. This enables the system to learn how to distinguish correct from incorrect results, with respect to the implemented numerical schemes. Considering that decision-support systems for nuclear emergency management are used in a safety-critical application context, the methods introduced in this paper help improve the reliability of the system and the trustworthiness of the simulation results used by emergency managers in the decision making process. The effectiveness of the approach has been assessed using the atmospheric dispersion forecasts of two test versions of the widely used RODOS DSNE system.

  14. Strategy of Trade-Reliable Featured Product Supporting Regional Innovation Systems

    Science.gov (United States)

    Riskiawan, H. Y.; Purnomo, B. H.; Abdurahman, A.; Hariono, B.; Puspitasari, T. D.

    2018-01-01

    Pacitan, Ponorogo, and Magetan had planned the development of featured products as contained in the Medium Term Development Plan (MTDP) until 2020. The focus of development is almost similar to featured products derived from agribusiness, food processing, handycrafts, and tourism. The geographical proximity results characteristics of natural resources and social culture have similarities, including the type of featured products, constraints, problems, and opportunities for development. Given the characteristics and the support system of some featured products contained in these three regions have a lot in common and their functional interactions involving actors from across the region, it is necessary to develop cross-jurisdictional policy. The resulting strategy should be able to support the development of Regional Innovation System (RIS). The purpose of this research is 1) Determining featured product cross-regional between Pacitan regency; Ponorogo and Magetan districts in support of RIS development; and 2) Designing a featured product development strategy using supply chain management in order to drive the local economy. Based on the results of research conducted, featured products across the region that have potentiality to be developed are: processed products of “janggelan” leather products, and woven bamboo.

  15. Maintaining evolvability.

    Science.gov (United States)

    Crow, James F

    2008-12-01

    Although molecular methods, such as QTL mapping, have revealed a number of loci with large effects, it is still likely that the bulk of quantitative variability is due to multiple factors, each with small effect. Typically, these have a large additive component. Conventional wisdom argues that selection, natural or artificial, uses up additive variance and thus depletes its supply. Over time, the variance should be reduced, and at equilibrium be near zero. This is especially expected for fitness and traits highly correlated with it. Yet, populations typically have a great deal of additive variance, and do not seem to run out of genetic variability even after many generations of directional selection. Long-term selection experiments show that populations continue to retain seemingly undiminished additive variance despite large changes in the mean value. I propose that there are several reasons for this. (i) The environment is continually changing so that what was formerly most fit no longer is. (ii) There is an input of genetic variance from mutation, and sometimes from migration. (iii) As intermediate-frequency alleles increase in frequency towards one, producing less variance (as p --> 1, p(1 - p) --> 0), others that were originally near zero become more common and increase the variance. Thus, a roughly constant variance is maintained. (iv) There is always selection for fitness and for characters closely related to it. To the extent that the trait is heritable, later generations inherit a disproportionate number of genes acting additively on the trait, thus increasing genetic variance. For these reasons a selected population retains its ability to evolve. Of course, genes with large effect are also important. Conspicuous examples are the small number of loci that changed teosinte to maize, and major phylogenetic changes in the animal kingdom. The relative importance of these along with duplications, chromosome rearrangements, horizontal transmission and polyploidy

  16. Telepsychiatry clinical decision support system used by non-psychiatrists in remote areas: Validity & reliability of diagnostic module

    Science.gov (United States)

    Malhotra, Savita; Chakrabarti, Subho; Shah, Ruchita; Sharma, Minali; Sharma, Kanu Priya; Malhotra, Akanksha; Upadhyaya, Suneet K.; Margoob, Mushtaq A.; Maqbool, Dar; Jassal, Gopal D.

    2017-01-01

    Background & objectives: A knowledge-based, logically-linked online telepsychiatric decision support system for diagnosis and treatment of mental disorders was developed and validated. We evaluated diagnostic accuracy and reliability of the application at remote sites when used by non-psychiatrists who underwent a brief training in its use through video-conferencing. Methods: The study was conducted at a nodal telepsychiatry centre, and three geographically remote peripheral centres. The diagnostic tool of application had a screening followed by detailed criteria-wise diagnostic modules for 18 psychiatric disorders. A total of 100 consecutive consenting adult outpatients attending remote telepsychiatry centres were included. To assess inter-rater reliability, patients were interviewed face to face by non-specialists at remote sites using the application (active interviewer) and simultaneously on online application via video-conferencing by a passive assessor at nodal centre. Another interviewer at the nodal centre rated the patient using Mini-International Neuropsychiatric Interview (MINI) for diagnostic validation. Results: Screening sub-module had high sensitivity (80-100%), low positive predictive values (PPV) (0.10-0.71) but high negative predictive value (NPV) (0.97-1) for most disorders. For the diagnostic sub-modules, Cohen's kappa was >0.4 for all disorders, with kappa of 0.7-1.0 for most disorders. PPV and NPV were high for most disorders. Inter-rater agreement analysis revealed kappa >0.6 for all disorders. Interpretation & conclusions: Diagnostic tool showed acceptable to good validity and reliability when used by non-specialists at remote sites. Our findings show that diagnostic tool of the telepsychiatry application has potential to empower non-psychiatrist doctors and paramedics to diagnose psychiatric disorders accurately and reliably in remote sites. PMID:29265020

  17. Evaluation of the reliability concerning the identification of human factors as contributing factors by a computer supported event analysis (CEA)

    International Nuclear Information System (INIS)

    Wilpert, B.; Maimer, H.; Loroff, C.

    2000-01-01

    The project's objectives are the evaluation of the reliability concerning the identification of Human Factors as contributing factors by a computer supported event analysis (CEA). CEA is a computer version of SOL (Safety through Organizational Learning). Parts of the first step were interviews with experts from the nuclear power industry and the evaluation of existing computer supported event analysis methods. This information was combined to a requirement profile for the CEA software. The next step contained the implementation of the software in an iterative process of evaluation. The completion of this project was the testing of the CEA software. As a result the testing demonstrated that it is possible to identify contributing factors with CEA validly. In addition, CEA received a very positive feedback from the experts. (orig.) [de

  18. Demonstrating Reliable High Level Waste Slurry Sampling Techniques to Support Hanford Waste Processing

    Energy Technology Data Exchange (ETDEWEB)

    Kelly, Steven E.

    2013-11-11

    The Hanford Tank Operations Contractor (TOC) and the Hanford Waste Treatment and Immobilization Plant (WTP) contractor are both engaged in demonstrating mixing, sampling, and transfer system capability using simulated Hanford High-Level Waste (HL W) formulations. This work represents one of the remaining technical issues with the high-level waste treatment mission at Hanford. The TOC must demonstrate the ability to adequately mix and sample high-level waste feed to meet the WTP Waste Acceptance Criteria and Data Quality Objectives. The sampling method employed must support both TOC and WTP requirements. To facilitate information transfer between the two facilities the mixing and sampling demonstrations are led by the One System Integrated Project Team. The One System team, Waste Feed Delivery Mixing and Sampling Program, has developed a full scale sampling loop to demonstrate sampler capability. This paper discusses the full scale sampling loops ability to meet precision and accuracy requirements, including lessons learned during testing. Results of the testing showed that the Isolok(R) sampler chosen for implementation provides precise, repeatable results. The Isolok(R) sampler accuracy as tested did not meet test success criteria. Review of test data and the test platform following testing by a sampling expert identified several issues regarding the sampler used to provide reference material used to judge the Isolok's accuracy. Recommendations were made to obtain new data to evaluate the sampler's accuracy utilizing a reference sampler that follows good sampling protocol.

  19. Demonstrating Reliable High Level Waste Slurry Sampling Techniques to Support Hanford Waste Processing

    International Nuclear Information System (INIS)

    Kelly, Steven E.

    2013-01-01

    The Hanford Tank Operations Contractor (TOC) and the Hanford Waste Treatment and Immobilization Plant (WTP) contractor are both engaged in demonstrating mixing, sampling, and transfer system capability using simulated Hanford High-Level Waste (HL W) formulations. This work represents one of the remaining technical issues with the high-level waste treatment mission at Hanford. The TOC must demonstrate the ability to adequately mix and sample high-level waste feed to meet the WTP Waste Acceptance Criteria and Data Quality Objectives. The sampling method employed must support both TOC and WTP requirements. To facilitate information transfer between the two facilities the mixing and sampling demonstrations are led by the One System Integrated Project Team. The One System team, Waste Feed Delivery Mixing and Sampling Program, has developed a full scale sampling loop to demonstrate sampler capability. This paper discusses the full scale sampling loops ability to meet precision and accuracy requirements, including lessons learned during testing. Results of the testing showed that the Isolok(R) sampler chosen for implementation provides precise, repeatable results. The Isolok(R) sampler accuracy as tested did not meet test success criteria. Review of test data and the test platform following testing by a sampling expert identified several issues regarding the sampler used to provide reference material used to judge the Isolok's accuracy. Recommendations were made to obtain new data to evaluate the sampler's accuracy utilizing a reference sampler that follows good sampling protocol

  20. Evaluating the Inter-Respondent (Consumer vs. Staff) Reliability and Construct Validity (SIS vs. Vineland) of the Supports Intensity Scale on a Dutch Sample

    Science.gov (United States)

    Claes, C.; Van Hove, G.; van Loon, J.; Vandevelde, S.; Schalock, R. L.

    2009-01-01

    Background: Despite various reliability studies on the Supports Intensity Scale (SIS), to date there has not been an evaluation of the reliability of client vs. staff judgments. Such determination is important, given the increasing consumer-driven approach to services. Additionally, there has not been an evaluation of the instrument's construct…

  1. Reliability and failure modes of implant-supported zirconium-oxide fixed dental prostheses related to veneering techniques

    Science.gov (United States)

    Baldassarri, Marta; Zhang, Yu; Thompson, Van P.; Rekow, Elizabeth D.; Stappert, Christian F. J.

    2011-01-01

    Summary Objectives To compare fatigue failure modes and reliability of hand-veneered and over-pressed implant-supported three-unit zirconium-oxide fixed-dental-prostheses(FDPs). Methods Sixty-four custom-made zirconium-oxide abutments (n=32/group) and thirty-two zirconium-oxide FDP-frameworks were CAD/CAM manufactured. Frameworks were veneered with hand-built up or over-pressed porcelain (n=16/group). Step-stress-accelerated-life-testing (SSALT) was performed in water applying a distributed contact load at the buccal cusp-pontic-area. Post failure examinations were carried out using optical (polarized-reflected-light) and scanning electron microscopy (SEM) to visualize crack propagation and failure modes. Reliability was compared using cumulative-damage step-stress analysis (Alta-7-Pro, Reliasoft). Results Crack propagation was observed in the veneering porcelain during fatigue. The majority of zirconium-oxide FDPs demonstrated porcelain chipping as the dominant failure mode. Nevertheless, fracture of the zirconium-oxide frameworks was also observed. Over-pressed FDPs failed earlier at a mean failure load of 696 ± 149 N relative to hand-veneered at 882 ± 61 N (profile I). Weibull-stress-number of cycles-unreliability-curves were generated. The reliability (2-sided at 90% confidence bounds) for a 400N load at 100K cycles indicated values of 0.84 (0.98-0.24) for the hand-veneered FDPs and 0.50 (0.82-0.09) for their over-pressed counterparts. Conclusions Both zirconium-oxide FDP systems were resistant under accelerated-life-time-testing. Over-pressed specimens were more susceptible to fatigue loading with earlier veneer chipping. PMID:21557985

  2. Introduction to the reliability and safety of mechanical supports. Einfuehrung in die Sicherheit und Zuverlaessigkeit von Tragwerken

    Energy Technology Data Exchange (ETDEWEB)

    Schueller, G I

    1981-01-01

    The book is divided into an introduction and three sections. The first section deals with the elements of statistics and the theory of probability. This section, providing also simple examples of application, is intended for such readers which up to now are not or only little familiar with the probabilistic philosophy and its application to problems of civil engineering. This section also is suited as an accompanying or supplementary text for an introductory lecture in this field and, as a matter of fact, is used as such by the author at Munich Technical University. The second section especially deals with the application of these methods to supporting structures, i.e. with the introduction to safety theory and reliability assessment of buildings. This section also treats the essential concepts and with the knowledge in probability theory and statistics already at hand or gained by studying the first section is easily understandable. Here also references are given concerning the elements of establishing standards and codes on the bases of probability theory. The last section deals with practical applications of safety reliability theory prepared in the preceeding section. This is done using engineering structures loaded by wind, seismic and wave forces.

  3. 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

  4. 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

  5. Development of KSC program for investigating and generating field failure rates. Volume 2: Recommended format for reliability handbook for ground support equipment

    Science.gov (United States)

    Bloomquist, C. E.; Kallmeyer, R. H.

    1972-01-01

    Field failure rates and confidence factors are presented for 88 identifiable components of the ground support equipment at the John F. Kennedy Space Center. For most of these, supplementary information regarding failure mode and cause is tabulated. Complete reliability assessments are included for three systems, eight subsystems, and nine generic piece-part classifications. Procedures for updating or augmenting the reliability results presented in this handbook are also included.

  6. Using software metrics and software reliability models to attain acceptable quality software for flight and ground support software for avionic systems

    Science.gov (United States)

    Lawrence, Stella

    1992-01-01

    This paper is concerned with methods of measuring and developing quality software. Reliable flight and ground support software is a highly important factor in the successful operation of the space shuttle program. Reliability is probably the most important of the characteristics inherent in the concept of 'software quality'. It is the probability of failure free operation of a computer program for a specified time and environment.

  7. A Reliability Generalization Study on the Survey of Perceived Organizational Support: The Effects of Mean Age and Number of Items on Score Reliability

    Science.gov (United States)

    Hellman, Chan M.; Fuqua, Dale R.; Worley, Jody

    2006-01-01

    The Survey of Perceived Organizational Support (SPOS) is a unidimensional measure of the general belief held by an employee that the organization is committed to him or her, values his or her continued membership, and is generally concerned about the employee's well-being. In the interest of efficiency, researchers are often compelled to use a…

  8. The order progress diagram : A supportive tool for diagnosing delivery reliability performance in make-to-order companies

    NARCIS (Netherlands)

    Soepenberg, G.D.; Land, M.J.; Gaalman, G.J.C.

    This paper describes the development of a new tool for facilitating the diagnosis of logistic improvement opportunities in make-to-order (MTO) companies. Competitiveness of these companies increasingly imposes needs upon delivery reliability. In order to achieve high delivery reliability, both the

  9. Examining the value of travel time reliability for freight transportation to support freight planning and decision-Making [summary].

    Science.gov (United States)

    2016-12-01

    As consumers demand greater choice and availability of products, suppliers have responded with more just-in-time delivery and less centralized inventories. Keeping this supply chain working efficiently requires reliable freight transportation. Delays...

  10. Examining the value of travel time reliability for freight transportation to support freight planning and decision-making.

    Science.gov (United States)

    2016-12-01

    This report presents the findings of a valuation study recently conducted in Florida to quantify the : freight users willingness to pay (WTP) for the improvement of transportation-related attributes, : particularly reliability. A stated preference...

  11. Seamless service: maintaining momentum.

    Science.gov (United States)

    Grinstead, N; Timoney, R

    1994-01-01

    Describes the process used by the Mater Infirmorum Hospital in Belfast in 1992-1994 to achieve high quality care (Seamless Service), motivate staff to deliver and measure performance. Aims of the project include focusing the organization on the customer, improving teamwork and motivation at all levels. After comprehensive data collection from GPs, patients and staff management forums developed a full TQM strategy to gain support and maintain momentum including innovative staff events (every staff member was given the opportunity to attend) where multilevel, multidisciplinary workshops enabled staff to design customer care standards, develop teams and lead customer-driven change.

  12. Mist1 Expressing Gastric Stem Cells Maintain the Normal and Neoplastic Gastric Epithelium and Are Supported by a Perivascular Stem Cell Niche

    Czech Academy of Sciences Publication Activity Database

    Hayakawa, Y.; Ariyama, H.; Stančíková, Jitka; Sakitani, S.; Asfaha, S.; Renz, B.W.; Dubeykovskaya, Z.A.; Shibata, W.; Wang, H.S.; Westphalen, C.B.; Chen, X.W.; Takemoto, Y.; Kim, W.; Khurana, S.S.; Tailor, Y.; Nagar, K.; Tomita, H.; Hara, A.; Sepulveda, A.R.; Setlik, W.; Gershon, M.D.; Saha, S.; Ding, L.; Shen, Z.L.; Fox, J.G.; Friedman, R.A.; Konieczny, S.F.; Worthley, D.; Kořínek, Vladimír; Wang, T.C.

    2015-01-01

    Roč. 28, č. 6 (2015), s. 800-814 ISSN 1535-6108 R&D Projects: GA ČR GAP305/11/1780; GA ČR(CZ) GA14-33952S Institutional support: RVO:68378050 Keywords : Innate lymphoid-cells * Intraepithelial neoplasia * Maintenance Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 23.214, year: 2015

  13. A reliability study on brain activation during active and passive arm movements supported by an MRI-compatible robot.

    Science.gov (United States)

    Estévez, Natalia; Yu, Ningbo; Brügger, Mike; Villiger, Michael; Hepp-Reymond, Marie-Claude; Riener, Robert; Kollias, Spyros

    2014-11-01

    In neurorehabilitation, longitudinal assessment of arm movement related brain function in patients with motor disability is challenging due to variability in task performance. MRI-compatible robots monitor and control task performance, yielding more reliable evaluation of brain function over time. The main goals of the present study were first to define the brain network activated while performing active and passive elbow movements with an MRI-compatible arm robot (MaRIA) in healthy subjects, and second to test the reproducibility of this activation over time. For the fMRI analysis two models were compared. In model 1 movement onset and duration were included, whereas in model 2 force and range of motion were added to the analysis. Reliability of brain activation was tested with several statistical approaches applied on individual and group activation maps and on summary statistics. The activated network included mainly the primary motor cortex, primary and secondary somatosensory cortex, superior and inferior parietal cortex, medial and lateral premotor regions, and subcortical structures. Reliability analyses revealed robust activation for active movements with both fMRI models and all the statistical methods used. Imposed passive movements also elicited mainly robust brain activation for individual and group activation maps, and reliability was improved by including additional force and range of motion using model 2. These findings demonstrate that the use of robotic devices, such as MaRIA, can be useful to reliably assess arm movement related brain activation in longitudinal studies and may contribute in studies evaluating therapies and brain plasticity following injury in the nervous system.

  14. Formulação estratégica da manutenção industrial com base na confiabilidade dos equipamentos Strategic formulation of industrial maintenance supported by equipment's reliability

    Directory of Open Access Journals (Sweden)

    Miguel Afonso Sellitto

    2005-04-01

    Full Text Available Este trabalho relata o uso da confiabilidade e da manutenibilidade na formulação de estratégias de manutenção industrial. O método utilizado foi o estudo de dois casos. Inicia-se revisando conceitos ligados a variáveis e processos aleatórios como base para definir conceitos e características de estudos de confiabilidade e de modelagem aplicados na gestão da manutenção industrial. A seguir se descrevem os casos estudados, em que se aplicam técnicas de modelagem de tempos até a falha e até o reparo no estabelecimento de estratégias de manutenção em fábricas do setor metal-mecânico. Com base nos resultados, discute-se o caso, estabelecendo condições para o uso da confiabilidade na formulação estratégica da manutenção, principalmente quanto ao sistema de informações necessárias.This paper reports the use of reliability and maintainability assessments in the strategic formulation of industrial maintenance. The method was a double case study. The paper begins by a theoretical review of related concepts of stochastic variables and processes as a basis to address concepts and features from reliability studies and modeling, suited to use in managing the industrial maintenance. One then describes the two studied cases, in which the reliability techniques were applied, in modeling the times to failure and times to the repair for the sake of settling the strategic formulation of industrial maintenance in metal-mechanic plants. Supported by results, this paper discusses the cases, arising requirements to the use of the reliability, mainly related to the information system.

  15. Factorial validity and reliability of the Malaysian simplified Chinese version of Multidimensional Scale of Perceived Social Support (MSPSS-SCV) among a group of university students.

    Science.gov (United States)

    Guan, Ng Chong; Seng, Loh Huai; Hway Ann, Anne Yee; Hui, Koh Ong

    2015-03-01

    This study was aimed at validating the simplified Chinese version of the Multidimensional Scale of Perceived Support (MSPSS-SCV) among a group of medical and dental students in University Malaya. Two hundred and two students who took part in this study were given the MSPSS-SCV, the Medical Outcome Study social support survey, the Malay version of the Beck Depression Inventory, the Malay version of the General Health Questionnaire, and the English version of the MSPSS. After 1 week, these students were again required to complete the MSPSS-SCV but with the item sequences shuffled. This scale displayed excellent internal consistency (Cronbach's α = .924), high test-retest reliability (.71), parallel form reliability (.92; Spearman's ρ, P students. It could therefore be used as a simple screening tool among young educated Malaysian adolescents. © 2013 APJPH.

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

    Science.gov (United States)

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

    2016-01-01

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

  17. Design for reliability: NASA reliability preferred practices for design and test

    Science.gov (United States)

    Lalli, Vincent R.

    1994-01-01

    This tutorial summarizes reliability experience from both NASA and industry and reflects engineering practices that support current and future civil space programs. These practices were collected from various NASA field centers and were reviewed by a committee of senior technical representatives from the participating centers (members are listed at the end). The material for this tutorial was taken from the publication issued by the NASA Reliability and Maintainability Steering Committee (NASA Reliability Preferred Practices for Design and Test. NASA TM-4322, 1991). Reliability must be an integral part of the systems engineering process. Although both disciplines must be weighed equally with other technical and programmatic demands, the application of sound reliability principles will be the key to the effectiveness and affordability of America's space program. Our space programs have shown that reliability efforts must focus on the design characteristics that affect the frequency of failure. Herein, we emphasize that these identified design characteristics must be controlled by applying conservative engineering principles.

  18. A Sustainable, Reliable Mission-Systems Architecture that Supports a System of Systems Approach to Space Exploration

    Science.gov (United States)

    Watson, Steve; Orr, Jim; O'Neil, Graham

    2004-01-01

    A mission-systems architecture based on a highly modular "systems of systems" infrastructure utilizing open-standards hardware and software interfaces as the enabling technology is absolutely essential for an affordable and sustainable space exploration program. This architecture requires (a) robust communication between heterogeneous systems, (b) high reliability, (c) minimal mission-to-mission reconfiguration, (d) affordable development, system integration, and verification of systems, and (e) minimum sustaining engineering. This paper proposes such an architecture. Lessons learned from the space shuttle program are applied to help define and refine the model.

  19. 76 FR 58101 - Electric Reliability Organization Interpretation of Transmission Operations Reliability Standard

    Science.gov (United States)

    2011-09-20

    ....C. Cir. 2009). \\4\\ Mandatory Reliability Standards for the Bulk-Power System, Order No. 693, FERC... for maintaining real and reactive power balance. \\14\\ Electric Reliability Organization Interpretation...; Order No. 753] Electric Reliability Organization Interpretation of Transmission Operations Reliability...

  20. Strategies and Decision Support Systems for Integrating Variable Energy Resources in Control Centers for Reliable Grid Operations

    Energy Technology Data Exchange (ETDEWEB)

    Jones, Lawrence E. [Alstom Grid Inc., Washington, DC (United States)

    2011-11-01

    This report provides findings from the field regarding the best ways in which to guide operational strategies, business processes and control room tools to support the integration of renewable energy into electrical grids.

  1. Strategies and Decision Support Systems for Integrating Variable Energy Resources in Control Centers for Reliable Grid Operations. Executive Summary

    Energy Technology Data Exchange (ETDEWEB)

    Jones, Lawrence E. [Alstom Grid, Inc., Washington, DC (United States)

    2011-11-01

    This is the executive summary for a report that provides findings from the field regarding the best ways in which to guide operational strategies, business processes and control room tools to support the integration of renewable energy into electrical grids.

  2. An analysis of reliability and validity of the papilla index score of implant-supported single crowns of maxillary central incisors

    DEFF Research Database (Denmark)

    Peng, Min; Fei, Wei; Hosseini, Mandana

    2012-01-01

    Objectives: To test the reliability and validity of the papilla index scores of the implant-supported single crowns (ISSCs) of maxillary central incisors. Materials and Methods: Twenty-five patients with 25 ISSCs were included. Two prosthodontists evaluated the papilla index score (PIS) of three...... inter-observer agreement. The PIS score demonstrated significant correlation to the corresponding PP value (rs=.567, p=.000). Conclusions: The feasibility, reliability and validity of the PIS made the parameter useful for quality control of the pri-implant soft tissue of ISSCs....... fill percent (PP) was calculated. The validity of PIS was tested against the corresponding papilla fill percent (PP) by using the Spearman correlation analysis. Results: The intra-observer agreement was >70% in 4/5 and >50% in all observations, the pooled Cohen’s ¿ was 0.64 and 0.70 for two observers...

  3. 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.

  4. Initial Assessment for K-12 English Language Support in Six Countries: Revisiting the Validity-Reliability Paradox

    Science.gov (United States)

    Sinclair, Jeanne; Lau, Clarissa

    2018-01-01

    It is common practice for K-12 schools to assess multilingual students' language proficiency to determine language support program placement. Because such programs can provide essential scaffolding, the policies guiding these assessments merit careful consideration. It is well accepted that quality assessments must be valid (representative of the…

  5. Needs Assessment in STEM Disciplines: Reliability, Validity and Factor Structure of the Student Support Needs Scale (SSNS)

    Science.gov (United States)

    Hardy, Precious; Aruguete, Mara

    2014-01-01

    Retention is a major problem in most colleges and universities. High dropout rates, especially in the STEM disciplines (science, technology, engineering and mathematics), have proved intractable despite the offering of supplemental instruction. A broad model of support systems that includes psychological factors is needed to address retention in…

  6. [Maintaining patients' autonomy at home].

    Science.gov (United States)

    Niang, Bénédicte; Coudre, Jean Pierre

    2015-01-01

    To maintain the flow of hospital discharges, the patient's return home with support from a home nursing service is important. If any difficulties are identified, there are various programmes or good practices which can be put into place. The future law on adapting society to ageing also comprises a scheme combining home assistance and nursing care.

  7. Maintaining steam/condensate lines

    International Nuclear Information System (INIS)

    Russum, S.A.

    1992-01-01

    Steam and condensate systems must be maintained with the same diligence as the boiler itself. Unfortunately, they often are not. The water treatment program, critical to keeping the boiler at peak efficiency and optimizing operating life, should not stop with the boiler. The program must encompass the steam and condensate system as well. A properly maintained condensate system maximizes condensate recovery, which is a cost-free energy source. The fuel needed to turn the boiler feedwater into steam has already been provided. Returning the condensate allows a significant portion of that fuel cost to be recouped. Condensate has a high heat content. Condensate is a readily available, economical feedwater source. Properly treated, it is very pure. Condensate improves feedwater quality and reduces makeup water demand and pretreatment costs. Higher quality feedwater means more reliable boiler operation

  8. 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)

  9. Systems reliability analysis for the national ignition facility

    International Nuclear Information System (INIS)

    Majumdar, K.C.; Annese, C.E.; MacIntyre, A.T.; Sicherman, A.

    1996-01-01

    A Reliability, Availability and Maintainability (RAM) analysis was initiated for the National Ignition Facility (NIF). The NIF is an inertial confinement fusion research facility designed to achieve controlled thermonuclear reaction; the preferred site for the NIF is the Lawrence Livermore National Laboratory (LLNL). The NIF RAM analysis has three purposes: (1) to allocate top level reliability and availability goals for the systems, (2) to develop an operability model for optimum maintainability, and (3) to determine the achievability of the allocated goals of the RAM parameters for the NIF systems and the facility operation as a whole. An allocation model assigns the reliability and availability goals for front line and support systems by a top-down approach; reliability analysis uses a bottom-up approach to determine the system reliability and availability from component level to system level

  10. Cost on Reliability and Production Loss for Power Converters in the Doubly Fed Induction Generator to Support Modern Grid Codes

    DEFF Research Database (Denmark)

    Zhou, Dao; Blaabjerg, Frede; Lau, Mogens

    2016-01-01

    As wind farms are normally located in remote areas, many grid codes have been issued especially related to the reactive power support. Although the Doubly-Fed Induction Generator (DFIG) based power converter is able to control the active power and reactive power independently, the effects...... of providing reactive power on the lifetime of the power converter and the cost-of-energy of the whole system are seldom evaluated, even though it is an important topic. In this paper, the loss models of the DFIG system are established at various conditions of the reactive power injection. If the mission...... profile is taken into account, the lifespan of the power semiconductors as well as the cost of the reactive power can be calculated. It is concluded that an over-excited reactive power injection significantly reduces the power converter lifetime, only 1/4 of the case that there is no reactive power...

  11. 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

  12. 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.

  13. ADAS Update and Maintainability

    Science.gov (United States)

    Watson, Leela R.

    2010-01-01

    Since 2000, both the National Weather Service Melbourne (NWS MLB) and the Spaceflight Meteorology Group (SMG) have used a local data integration system (LOIS) as part of their forecast and warning operations. The original LOIS was developed by the Applied Meteorology Unit (AMU) in 1998 (Manobianco and Case 1998) and has undergone subsequent improvements. Each has benefited from three-dimensional (3-D) analyses that are delivered to forecasters every 15 minutes across the peninsula of Florida. The intent is to generate products that enhance short-range weather forecasts issued in support of NWS MLB and SMG operational requirements within East Central Florida. The current LDIS uses the Advanced Regional Prediction System (ARPS) Data Analysis System (AD AS) package as its core, which integrates a wide variety of national, regional, and local observational data sets. It assimilates all available real-time data within its domain and is run at a finer spatial and temporal resolution than current national or regional-scale analysis packages. As such, it provides local forecasters with a more comprehensive understanding of evolving fine-scale weather features. Over the years, the LDIS has become problematic to maintain since it depends on AMU-developed shell scripts that were written for an earlier version of the ADAS software. The goals of this task were to update the NWS MLB/SMG LDIS with the latest version of ADAS, incorporate new sources of observational data, and upgrade and modify the AMU-developed shell scripts written to govern the system. In addition, the previously developed ADAS graphical user interface (GUI) was updated. Operationally, these upgrades will result in more accurate depictions of the current local environment to help with short-range weather forecasting applications, while also offering an improved initialization for local versions of the Weather Research and Forecasting (WRF) model used by both groups.

  14. Protein Based Molecular Markers Provide Reliable Means to Understand Prokaryotic Phylogeny and Support Darwinian Mode of Evolution

    Directory of Open Access Journals (Sweden)

    Vaibhav eBhandari

    2012-07-01

    Full Text Available The analyses of genome sequences have led to the proposal that lateral gene transfers (LGTs among prokaryotes are so widespread that they disguise the interrelationships among these organisms. This has led to questioning whether the Darwinian model of evolution is applicable to the prokaryotic organisms. In this review, we discuss the usefulness of taxon-specific molecular markers such as conserved signature indels (CSIs and conserved signature proteins (CSPs for understanding the evolutionary relationships among prokaryotes and to assess the influence of LGTs on prokaryotic evolution. The analyses of genomic sequences have identified large numbers of CSIs and CSPs that are unique properties of different groups of prokaryotes ranging from phylum to genus levels. The species distribution patterns of these molecular signatures strongly support a tree-like vertical inheritance of the genes containing these molecular signatures that is consistent with phylogenetic trees. Recent detailed studies in this regard on Thermotogae and Archaea, which are reviewed here, have identified large numbers of CSIs and CSPs that are specific for the species from these two taxa and a number of their major clades. The genetic changes responsible for these CSIs (and CSPs initially likely occurred in the common ancestors of these taxa and then vertically transferred to various descendants. Although some CSIs and CSPs in unrelated groups of prokaryotes were identified, their small numbers and random occurrence has no apparent influence on the consistent tree-like branching pattern emerging from other markers. These results provide evidence that although LGT is an important evolutionary force, it does not mask the tree-like branching pattern of prokaryotes or understanding of their evolutionary relationships. The identified CSIs and CSPs also provide novel and highly specific means for identification of different groups of microbes and for taxonomical and biochemical

  15. Protein based molecular markers provide reliable means to understand prokaryotic phylogeny and support Darwinian mode of evolution.

    Science.gov (United States)

    Bhandari, Vaibhav; Naushad, Hafiz S; Gupta, Radhey S

    2012-01-01

    The analyses of genome sequences have led to the proposal that lateral gene transfers (LGTs) among prokaryotes are so widespread that they disguise the interrelationships among these organisms. This has led to questioning of whether the Darwinian model of evolution is applicable to prokaryotic organisms. In this review, we discuss the usefulness of taxon-specific molecular markers such as conserved signature indels (CSIs) and conserved signature proteins (CSPs) for understanding the evolutionary relationships among prokaryotes and to assess the influence of LGTs on prokaryotic evolution. The analyses of genomic sequences have identified large numbers of CSIs and CSPs that are unique properties of different groups of prokaryotes ranging from phylum to genus levels. The species distribution patterns of these molecular signatures strongly support a tree-like vertical inheritance of the genes containing these molecular signatures that is consistent with phylogenetic trees. Recent detailed studies in this regard on the Thermotogae and Archaea, which are reviewed here, have identified large numbers of CSIs and CSPs that are specific for the species from these two taxa and a number of their major clades. The genetic changes responsible for these CSIs (and CSPs) initially likely occurred in the common ancestors of these taxa and then vertically transferred to various descendants. Although some CSIs and CSPs in unrelated groups of prokaryotes were identified, their small numbers and random occurrence has no apparent influence on the consistent tree-like branching pattern emerging from other markers. These results provide evidence that although LGT is an important evolutionary force, it does not mask the tree-like branching pattern of prokaryotes or understanding of their evolutionary relationships. The identified CSIs and CSPs also provide novel and highly specific means for identification of different groups of microbes and for taxonomical and biochemical studies.

  16. Ergonomics Contribution in Maintainability

    Science.gov (United States)

    Teymourian, Kiumars; Seneviratne, Dammika; Galar, Diego

    2017-09-01

    The objective of this paper is to describe an ergonomics contribution in maintainability. The economical designs, inputs and training helps to increase the maintainability indicators for industrial devices. This analysis can be helpful, among other cases, to compare systems, to achieve a better design regarding maintainability requirements, to improve this maintainability under specific industrial environment and to foresee maintainability problems due to eventual changes in a device operation conditions. With this purpose, this work first introduces the notion of ergonomics and human factors, maintainability and the implementation of assessment of human postures, including some important postures to perform maintenance activities. A simulation approach is used to identify the critical posture of the maintenance personnel and implements the defined postures with minimal loads on the personnel who use the equipment in a practical scenario. The simulation inputs are given to the designers to improve the workplace/equipment in order to high level of maintainability. Finally, the work concludes summarizing the more significant aspects and suggesting future research.

  17. Reliability analysis techniques in power plant design

    International Nuclear Information System (INIS)

    Chang, N.E.

    1981-01-01

    An overview of reliability analysis techniques is presented as applied to power plant design. The key terms, power plant performance, reliability, availability and maintainability are defined. Reliability modeling, methods of analysis and component reliability data are briefly reviewed. Application of reliability analysis techniques from a design engineering approach to improving power plant productivity is discussed. (author)

  18. Validity and reliability of the "German Utilization Questionnaire-Dissemination and Use of Research" to measure attitude, availability, and support toward implementation of research in nursing practice.

    Science.gov (United States)

    Haslinger-Baumann, Elisabeth; Lang, Gert; Müller, Gerhard

    2014-01-01

    In nursing practice, research results have to undergo a systematic process of transformation. Currently in Austria, there is no empirical data available concerning the actual implementation of research results. An English validated questionnaire was translated into German and tested for validity and reliability. A survey of 178 registered nurses (n = 178) was conducted in a multicenter, quantitative, cross-sectional study in Austria in 2011. Cronbach's alpha values (.82-.92) were calculated for 4 variables ("use," "attitude," "availability," "support") after the reduction of 7 irrelevant items. Exploratory factor analysis was calculated with Kaiser-Meyer-Olkin (KMO) ranging from .78 to .92; the total variance ranged from 46% to 56%. A validated German questionnaire concerning the implementation of research results is now available for the nursing practice.

  19. 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)

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

    Energy Technology Data Exchange (ETDEWEB)

    none,

    2014-09-30

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

  1. Maintaining dignity in vulnerability

    DEFF Research Database (Denmark)

    Høy, Bente

    2016-01-01

    to understand the meaning of the narrated text. Results. The meaning of maintaining dignity was constituted in a sense of vulnerability to the self, and elucidated in three major interrelated themes: Being involved as a human being, being involved as the person one is and strives to become, and being involved...

  2. Disturbance maintains alternative biome states.

    Science.gov (United States)

    Dantas, Vinícius de L; Hirota, Marina; Oliveira, Rafael S; Pausas, Juli G

    2016-01-01

    Understanding the mechanisms controlling the distribution of biomes remains a challenge. Although tropical biome distribution has traditionally been explained by climate and soil, contrasting vegetation types often occur as mosaics with sharp boundaries under very similar environmental conditions. While evidence suggests that these biomes are alternative states, empirical broad-scale support to this hypothesis is still lacking. Using community-level field data and a novel resource-niche overlap approach, we show that, for a wide range of environmental conditions, fire feedbacks maintain savannas and forests as alternative biome states in both the Neotropics and the Afrotropics. In addition, wooded grasslands and savannas occurred as alternative grassy states in the Afrotropics, depending on the relative importance of fire and herbivory feedbacks. These results are consistent with landscape scale evidence and suggest that disturbance is a general factor driving and maintaining alternative biome states and vegetation mosaics in the tropics. © 2015 John Wiley & Sons Ltd/CNRS.

  3. 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.

  4. Designing reliability into accelerators

    International Nuclear Information System (INIS)

    Hutton, A.

    1992-08-01

    For the next generation of high performance, high average luminosity colliders, the ''factories,'' reliability engineering must be introduced right at the inception of the project and maintained as a central theme throughout the project. There are several aspects which will be addressed separately: Concept; design; motivation; management techniques; and fault diagnosis

  5. 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

  6. Constructability and maintainability

    International Nuclear Information System (INIS)

    Hart, R.S.

    1985-01-01

    A set of principles for minimizing the construction schedule was established at the outset of the CANDU 300 programme. Consideration of these principles and other factors led to the development of the unique CANDU 300 station layout. The paper discusses the CANDU 300 station layout and construction methods. In summary, the station layout provides 360 deg. construction access to all buildings, separation of nuclear and non-nuclear systems, precise and minimal physical interfaces between buildings, accommodation of many contractors and construction activities without interference, and maximum flexibility in terms of constructional, financial and supply arrangements. The CANDU 300 further employs modularization, shop fabrication and advanced instrumentation (multiplexers, remote processors, data highways) to minimize construction time. Many of the CANDU 300 features that enhance constructability also contribute to maintainability. These include the 360 deg. access to all principal buildings, the uncluttered and spacious building layouts, the simplification of systems and the high level of modularization. The CANDU 300 has also been designed to facilitate the replacement of all key components, thereby offering an essentially unlimited station life. A prime example is a reduction in the fuel channel inlet end-fitting diameter such that the fuel channels can be shop assembled and easily replaced after the initial 40 years of operation, without an extended unit outage. Maintainability within the reactor building has been given particular attention in the CANDU 300 design; key features of other CANDU reactors (the ability to replace a heat transport system pump motor at power, for example) have been incorporated, while accessibility and maintainability of all systems and components have been enhanced. These and other aspects of maintainability are discussed. (author)

  7. 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

  8. SuperTRI: A new approach based on branch support analyses of multiple independent data sets for assessing reliability of phylogenetic inferences.

    Science.gov (United States)

    Ropiquet, Anne; Li, Blaise; Hassanin, Alexandre

    2009-09-01

    Supermatrix and supertree are two methods for constructing a phylogenetic tree by using multiple data sets. However, these methods are not a panacea, as conflicting signals between data sets can lead to misinterpret the evolutionary history of taxa. In particular, the supermatrix approach is expected to be misleading if the species-tree signal is not dominant after the combination of the data sets. Moreover, most current supertree methods suffer from two limitations: (i) they ignore or misinterpret secondary (non-dominant) phylogenetic signals of the different data sets; and (ii) the logical basis of node robustness measures is unclear. To overcome these limitations, we propose a new approach, called SuperTRI, which is based on the branch support analyses of the independent data sets, and where the reliability of the nodes is assessed using three measures: the supertree Bootstrap percentage and two other values calculated from the separate analyses: the mean branch support (mean Bootstrap percentage or mean posterior probability) and the reproducibility index. The SuperTRI approach is tested on a data matrix including seven genes for 82 taxa of the family Bovidae (Mammalia, Ruminantia), and the results are compared to those found with the supermatrix approach. The phylogenetic analyses of the supermatrix and independent data sets were done using four methods of tree reconstruction: Bayesian inference, maximum likelihood, and unweighted and weighted maximum parsimony. The results indicate, firstly, that the SuperTRI approach shows less sensitivity to the four phylogenetic methods, secondly, that it is more accurate to interpret the relationships among taxa, and thirdly, that interesting conclusions on introgression and radiation can be drawn from the comparisons between SuperTRI and supermatrix analyses.

  9. Gestures maintain spatial imagery.

    Science.gov (United States)

    Wesp, R; Hesse, J; Keutmann, D; Wheaton, K

    2001-01-01

    Recent theories suggest alternatives to the commonly held belief that the sole role of gestures is to communicate meaning directly to listeners. Evidence suggests that gestures may serve a cognitive function for speakers, possibly acting as lexical primes. We observed that participants gestured more often when describing a picture from memory than when the picture was present and that gestures were not influenced by manipulating eye contact of a listener. We argue that spatial imagery serves a short-term memory function during lexical search and that gestures may help maintain spatial images. When spatial imagery is not necessary, as in conditions of direct visual stimulation, reliance on gestures is reduced or eliminated.

  10. Maintainability design guide

    International Nuclear Information System (INIS)

    Pack, R.W.

    1985-01-01

    The Human Factors Design Guide for Maintainability provides guidance for systematically incorporating good human factors techniques into the design of power plants. The guide describes a means of developing a comprehensive program plan to ensure compliance with the human factors approaches specified by the utility. The guide also provides specific recommendations for design practices, with examples, bases, and references. The recommendations are formatted for easy use by nuclear power plant design teams and by utility personnel involved in specification and design review. The guide was developed under EPRI research project RP2166-4 and is currently being published

  11. Maintaining Your Health

    Science.gov (United States)

    ... bills, managing money, and filing tax returns; or buying groceries and cooking meals. Help your loved one ... help you modify your lifestyle and adopt healthier behaviors. These can include support groups, dieticians, and personal ...

  12. 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)

  13. 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...

  14. OSS reliability measurement and assessment

    CERN Document Server

    Yamada, Shigeru

    2016-01-01

    This book analyses quantitative open source software (OSS) reliability assessment and its applications, focusing on three major topic areas: the Fundamentals of OSS Quality/Reliability Measurement and Assessment; the Practical Applications of OSS Reliability Modelling; and Recent Developments in OSS Reliability Modelling. Offering an ideal reference guide for graduate students and researchers in reliability for open source software (OSS) and modelling, the book introduces several methods of reliability assessment for OSS including component-oriented reliability analysis based on analytic hierarchy process (AHP), analytic network process (ANP), and non-homogeneous Poisson process (NHPP) models, the stochastic differential equation models and hazard rate models. These measurement and management technologies are essential to producing and maintaining quality/reliable systems using OSS.

  15. Maintaining Relationship Based Procurement

    Directory of Open Access Journals (Sweden)

    Peter Davis

    2012-11-01

    Full Text Available Alliance and relationship projects are increasingin number and represent a large pool of work. Tobe successful relationship style contracts dependon soft-dollar factors, particularly the participants'ability to work together within an agreedframework, generally they are not based on lowbid tendering. Participants should be prepared todo business in an open environment based ontrust and mutually agreed governance. Theresearch evaluates relationship maintenance inthe implementation phase of constructionalliances - a particular derivative of relationshipstyle contracts. To determine the factors thatcontribute to relationship maintenance forty-nineexperienced Australian alliance projectmanagers were interviewed. The main findingswere; the development of relationships early inthe project form building blocks of success fromwhich relationships are maintained and projectvalue added; quality facilitation plays animportant part in relationship maintenance and ahybrid organisation created as a result of alliancedevelopment overcomes destructiveorganisational boundaries. Relationshipmaintenance is integral to alliance project controland failure to formalise it and pay attention toprocess and past outcomes will undermine analliance project's potential for success.

  16. Support Vector Machine Analysis of Functional Magnetic Resonance Imaging of Interoception Does Not Reliably Predict Individual Outcomes of Cognitive Behavioral Therapy in Panic Disorder with Agoraphobia

    Directory of Open Access Journals (Sweden)

    Benedikt Sundermann

    2017-06-01

    Full Text Available BackgroundThe approach to apply multivariate pattern analyses based on neuro imaging data for outcome prediction holds out the prospect to improve therapeutic decisions in mental disorders. Patients suffering from panic disorder with agoraphobia (PD/AG often exhibit an increased perception of bodily sensations. The purpose of this investigation was to assess whether multivariate classification applied to a functional magnetic resonance imaging (fMRI interoception paradigm can predict individual responses to cognitive behavioral therapy (CBT in PD/AG.MethodsThis analysis is based on pretreatment fMRI data during an interoceptive challenge from a multicenter trial of the German PANIC-NET. Patients with DSM-IV PD/AG were dichotomized as responders (n = 30 or non-responders (n = 29 based on the primary outcome (Hamilton Anxiety Scale Reduction ≥50% after 6 weeks of CBT (2 h/week. fMRI parametric maps were used as features for response classification with linear support vector machines (SVM with or without automated feature selection. Predictive accuracies were assessed using cross validation and permutation testing. The influence of methodological parameters and the predictive ability for specific interoception-related symptom reduction were further evaluated.ResultsSVM did not reach sufficient overall predictive accuracies (38.0–54.2% for anxiety reduction in the primary outcome. In the exploratory analyses, better accuracies (66.7% were achieved for predicting interoception-specific symptom relief as an alternative outcome domain. Subtle information regarding this alternative response criterion but not the primary outcome was revealed by post hoc univariate comparisons.ConclusionIn contrast to reports on other neurofunctional probes, SVM based on an interoception paradigm was not able to reliably predict individual response to CBT. Results speak against the clinical applicability of this technique.

  17. 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

  18. 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.

  19. Maintaining Web Cache Coherency

    Directory of Open Access Journals (Sweden)

    2000-01-01

    Full Text Available Document coherency is a challenging problem for Web caching. Once the documents are cached throughout the Internet, it is often difficult to keep them coherent with the origin document without generating a new traffic that could increase the traffic on the international backbone and overload the popular servers. Several solutions have been proposed to solve this problem, among them two categories have been widely discussed: the strong document coherency and the weak document coherency. The cost and the efficiency of the two categories are still a controversial issue, while in some studies the strong coherency is far too expensive to be used in the Web context, in other studies it could be maintained at a low cost. The accuracy of these analysis is depending very much on how the document updating process is approximated. In this study, we compare some of the coherence methods proposed for Web caching. Among other points, we study the side effects of these methods on the Internet traffic. The ultimate goal is to study the cache behavior under several conditions, which will cover some of the factors that play an important role in the Web cache performance evaluation and quantify their impact on the simulation accuracy. The results presented in this study show indeed some differences in the outcome of the simulation of a Web cache depending on the workload being used, and the probability distribution used to approximate updates on the cached documents. Each experiment shows two case studies that outline the impact of the considered parameter on the performance of the cache.

  20. Maintaining productive earthmover performance

    Energy Technology Data Exchange (ETDEWEB)

    Chadwick, J.

    1992-01-01

    Maintenance management is essential to a productive mining operation. 80-90% of maintenance should be planned, the rest emergency. Many earthmover manufacturers offer extensive services to optimize machine productivity, e.g. equipment management software. Product support agreements (PSA) are becoming more common in open pit operations. These are normally agreements between mines and equipment dealers to provide product support requirements based on who can provide what most efficiently. The advantages for the customer are known servicing, cost effectiveness, minimum capital investment, and the fact PSAs are responsive to change. The operating experience of Round Mountain Gold, USA, Crouch Mining, UK, and Unatrac and Tractor Equipment, Ghana with PSAs is discussed. Crouch Mining operate England's largest open-cast coal operation, the Stobswood mine, Northumberland under contract to British Coal's Opencast-Executive. Crouch has agreed repair and maintenance contracts with 3 different dealer organisations for 3 separate machine fleets i.e. hydraulic excavators, a backhoe and 2 face shovels; 2 blasthole drills; and the 13 caterpillar trucks. These repair and maintenance contracts are described. 4 refs., 6 photos

  1. 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)

  2. 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.)

  3. EFSA Panel on Dietetic Products, Nutrition and Allergies (NDA); Scientific Opinion on the substantiation of a health claim related to EffEXT™ and “helps to support joint function by maintaining low levels of plasma C-reactive protein” pursuant to Article 13(5) of Regulation (EC) No 1924/2006

    DEFF Research Database (Denmark)

    Tetens, Inge

    Following an application from Nutrilinks Sarl, submitted pursuant to Article 13(5) of Regulation (EC) No 1924/2006 via the Competent Authority of Belgium, the Panel on Dietetic Products, Nutrition and Allergies (NDA) was asked to deliver an opinion on the scientific substantiation of a health claim...... related to EffEXT™ and “helps to support joint function by maintaining low levels of plasma C‑reactive protein”. The Panel considers that EffEXT™, which is standardised pure krill oil, is sufficiently characterised. The claimed effect is “helps to support joint function by maintaining low levels of plasma...

  4. Application of support vector machines in the evaluation of reliability generation and transmission systems; Aplicacao de maquinas de vetores suporte na avaliacao da confiabilidade de sistemas de geracao e transmissao

    Energy Technology Data Exchange (ETDEWEB)

    Dutra, Wellington Damascena; Resende, Leonidas Chaves de [Universidade Federal de Sao Joao Del-Rei (UFSJ), MG (Brazil); Manso, Luiz Antonio da Fonseca; Silva, Armando Martins Leite da [Universidade Federal de Itajuba (UNIFEI), MG (Brazil)

    2010-07-01

    This paper presents a methodology for assessing the reliability indices for composite generation and transmission systems based on Support Vector Machines (SVM). The importance of SVMs is its high generalization ability. The SVMs are used to classify data into two distinct classes. These can be named positive and negative. Thus, the basic idea is to classify the system states into success or failure. For this, a pre-classification of states is achieved by performing the proposed SVM-based neural network, where the sampled states during the beginning of the non-sequential Monte Carlo simulation (MCS) are considered as input data for training and validation sets. By adopting this procedure, a large number of states are classified by a simple evaluation of the network, providing significant reductions in computational costs. The proposed methodology is applied to the IEEE Reliability Test System and to the IEEE Modified Reliability Test System. (author)

  5. Test of Gross Motor Development-3 (TGMD-3) with the Use of Visual Supports for Children with Autism Spectrum Disorder: Validity and Reliability

    Science.gov (United States)

    Allen, K. A.; Bredero, B.; Van Damme, T.; Ulrich, D. A.; Simons, J.

    2017-01-01

    The validity and reliability of the Test of Gross Motor Development-3 (TGMD-3) were measured, taking into consideration the preference for visual learning of children with autism spectrum disorder (ASD). The TGMD-3 was administered to 14 children with ASD (4-10 years) and 21 age-matched typically developing children under two conditions: TGMD-3…

  6. 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

  7. 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

  8. Reliability engineering theory and practice

    CERN Document Server

    Birolini, Alessandro

    2014-01-01

    This book shows how to build in, evaluate, and demonstrate reliability and availability of components, equipment, systems. It presents the state-of-theart of reliability engineering, both in theory and practice, and is based on the author's more than 30 years experience in this field, half in industry and half as Professor of Reliability Engineering at the ETH, Zurich. The structure of the book allows rapid access to practical results. This final edition extend and replace all previous editions. New are, in particular, a strategy to mitigate incomplete coverage, a comprehensive introduction to human reliability with design guidelines and new models, and a refinement of reliability allocation, design guidelines for maintainability, and concepts related to regenerative stochastic processes. The set of problems for homework has been extended. Methods & tools are given in a way that they can be tailored to cover different reliability requirement levels and be used for safety analysis. Because of the Appendice...

  9. Reliability risks during the transition to competitive electricity markets

    International Nuclear Information System (INIS)

    Hughes, J.P.

    2005-01-01

    The Electricity Consumers Resource Council (ELCON) is a U.S. association representing industrial consumers of electricity, and is a long-standing advocate of competition in the electric power industry. However, because a reliable grid is necessary to support competitive wholesale markets, ELCON believes that the transmission system is an essential facility that must remain regulated. The initiatives discussed in this white paper represent significant steps that the National Electric Reliability Council (NERC) and the industry have taken to improve reliability in a competitive and restructured electric industry. Strategic manoeuvres of incumbent utilities to maintain market share were evaluated, as well as discrimination against potential competitors. It was suggested that, occasionally, indecisive federal policies have been taken advantage of by utilities. The unintended consequences of state restructuring policies that allow utilities to over-earn their revenue requirements were reviewed. NERC reliability standards will remain unenforceable until a new Electricity Reliability Organization has been certified. Flawed market designs and inadequate market power mitigation, as well as the financial distress of merchant generators, pose considerable risks. It was suggested that these risks could trigger transmission loading relief incidents, local outages or widespread outages. In the absence of mandatory reliability standards with penalties, and complementary market rules for mitigating generation and transmission market power, economic incentives will encourage other forms of opportunistic behavior that may be the root cause of other outages. Public concern regarding these risks to grid reliability may result in lost public support for competitive electricity markets. Proposed solutions include the certification of a new Electric Reliability Organization to establish and enforce mandatory reliability standards, and granting the Federal Energy Regulatory Commission

  10. Accelerator Availability and Reliability Issues

    Energy Technology Data Exchange (ETDEWEB)

    Steve Suhring

    2003-05-01

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

  11. 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

  12. Intelligent social infrastructure technology. Infrastructure technology support ultra-reliable society; Chiteki shakai kiban kogaku gijutsu. Choanshin shakai wo sasaeru kiban gijutsu

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-03-01

    This survey was conducted to construct the core of intelligent social infrastructure technology (ISIT), and to investigate its practical application to industries and society. For realizing the ultra-safe and ultra-reliable society, it is necessary to develop the ISIT which can integrate various social infrastructures, such as architecture, city, energy, and lifeline systems required for living. For the systematization of cities, it is necessary to process and control the intelligent information by holding integrated and transverse information in common, as to logistics, lifeline, communication, monitoring, and control. For the communication engineering, the centralized systems are acceleratingly to be converted into the distributed network systems. For the mechanical engineering, intelligent control and robot technology are required. For the architectural engineering, a concept exceeding the conventional antiseismic structure idea is investigated. It is necessary to develop a new information technology providing an intelligent social infrastructures by merging the information networks and the physical world seamlessly. Necessity of ISIT is large for constructing the intelligent and ultra-reliable society consisting of these integrated and organized networks. 84 refs., 68 figs., 6 tabs.

  13. Reliability evaluation of power systems

    CERN Document Server

    Billinton, Roy

    1996-01-01

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

  14. Maintaining Healthy Skin -- Part 2

    Science.gov (United States)

    ... and SCI • Depression and SCI • Taking Care of Pressure Sores • Maintaining Healthy Skin (Part I) • Maintaining Healthy Skin ( ... For information on establishing skin tolerance, see our “Pressure Sores” pamphlet.) Pressure releases in a wheelchair can be ...

  15. Towards Reliable Integrated Services for Dependable Systems

    DEFF Research Database (Denmark)

    Schiøler, Henrik; Ravn, Anders Peter; Izadi-Zamanabadi, Roozbeh

    Reliability issues for various technical systems are discussed and focus is directed towards distributed systems, where communication facilities are vital to maintain system functionality. Reliability in communication subsystems is considered as a resource to be shared among a number of logical c...... applications residing on alternative routes. Details are provided for the operation of RRRSVP based on reliability slack calculus. Conclusions summarize the considerations and give directions for future research....... connections and a reliability management framework is suggested. We suggest a network layer level reliability management protocol RRSVP (Reliability Resource Reservation Protocol) as a counterpart of the RSVP for bandwidth and time resource management. Active and passive standby redundancy by background...

  16. Towards Reliable Integrated Services for Dependable Systems

    DEFF Research Database (Denmark)

    Schiøler, Henrik; Ravn, Anders Peter; Izadi-Zamanabadi, Roozbeh

    2003-01-01

    Reliability issues for various technical systems are discussed and focus is directed towards distributed systems, where communication facilities are vital to maintain system functionality. Reliability in communication subsystems is considered as a resource to be shared among a number of logical c...... applications residing on alternative routes. Details are provided for the operation of RRRSVP based on reliability slack calculus. Conclusions summarize the considerations and give directions for future research....... connections and a reliability management framework is suggested. We suggest a network layer level reliability management protocol RRSVP (Reliability Resource Reservation Protocol) as a counterpart of the RSVP for bandwidth and time resource management. Active and passive standby redundancy by background...

  17. The role of the American Society for Testing and Materials (ASTM) in providing standards to support reliability technology for nuclear power plants

    International Nuclear Information System (INIS)

    Steele, L.E.

    1978-01-01

    ASTM is an international society for managing the development of standards on characteristics and performance of materials, products, systems and services and the promotion of related knowledge. This paper provides on overview of ASTM, emphasizing its contribution to nuclear systems reliability. In so doing, the author, from his perspective as chairman of ASTM committee E 10 on ''Nuclear Applications and the Measurement of Radiation Effects and the Committee on Standards'', illustrates ASTM contributions to the understanding and control of radiation embrittlement of light-water reactor pressure vessels. Four major related taks are summarized and pertinent standards identified. These include: (1) surveillance practice (5 standards), (2) neutron dosimetry (8 standards), (3) specification for steels for nuclear service (7 standards) and (4) basic guidelines for thermal annealing to correct radiation embrittlement (1 standard). This illustration, a specific accomplishment using ASTM standards, is cited within the context of the broader nuclear-related activities of ASTM. (author)

  18. 78 FR 63036 - Transmission Planning Reliability Standards

    Science.gov (United States)

    2013-10-23

    ... Reliability Standards for the Bulk Power System, 130 FERC ] 61,200 (2010). \\8\\ Mandatory Reliability Standards... electric system operations across normal and contingency conditions. We also find that Reliability Standard... Reliability Standards for the Bulk Power System, 131 FERC ] 61,231 at P 21. Comments 24. NERC supports the...

  19. Reliability Centered Maintenance - Methodologies

    Science.gov (United States)

    Kammerer, Catherine C.

    2009-01-01

    Journal article about Reliability Centered Maintenance (RCM) methodologies used by United Space Alliance, LLC (USA) in support of the Space Shuttle Program at Kennedy Space Center. The USA Reliability Centered Maintenance program differs from traditional RCM programs because various methodologies are utilized to take advantage of their respective strengths for each application. Based on operational experience, USA has customized the traditional RCM methodology into a streamlined lean logic path and has implemented the use of statistical tools to drive the process. USA RCM has integrated many of the L6S tools into both RCM methodologies. The tools utilized in the Measure, Analyze, and Improve phases of a Lean Six Sigma project lend themselves to application in the RCM process. All USA RCM methodologies meet the requirements defined in SAE JA 1011, Evaluation Criteria for Reliability-Centered Maintenance (RCM) Processes. The proposed article explores these methodologies.

  20. 78 FR 58492 - Generator Verification Reliability Standards

    Science.gov (United States)

    2013-09-24

    ... power capability that is available for planning models and bulk electric system reliability assessments... of generator equipment needed to support Bulk-Power System reliability and enhance coordination of... support Bulk-Power System reliability and will ensure that accurate data is verified and made available...

  1. 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.

  2. Reliability of power electronic converter systems

    CERN Document Server

    Chung, Henry Shu-hung; Blaabjerg, Frede; Pecht, Michael

    2016-01-01

    This book outlines current research into the scientific modeling, experimentation, and remedial measures for advancing the reliability, availability, system robustness, and maintainability of Power Electronic Converter Systems (PECS) at different levels of complexity.

  3. Conventional multi-slice computed tomography (CT) and cone-beam CT (CBCT) for computer-aided implant placement. Part II: reliability of mucosa-supported stereolithographic guides.

    Science.gov (United States)

    Arisan, Volkan; Karabuda, Zihni Cüneyt; Pişkin, Bülent; Özdemir, Tayfun

    2013-12-01

    Deviations of implants that were placed by conventional computed tomography (CT)- or cone beam CT (CBCT)-derived mucosa-supported stereolithographic (SLA) surgical guides were analyzed in this study. Eleven patients were randomly scanned by a multi-slice CT (CT group) or a CBCT scanner (CBCT group). A total of 108 implants were planned on the software and placed using SLA guides. A new CT or CBCT scan was obtained and merged with the planning data to identify the deviations between the planned and placed implants. Results were analyzed by Mann-Whitney U test and multiple regressions (p < .05). Mean angular and linear deviations in the CT group were 3.30° (SD 0.36), and 0.75 (SD 0.32) and 0.80 mm (SD 0.35) at the implant shoulder and tip, respectively. In the CBCT group, mean angular and linear deviations were 3.47° (SD 0.37), and 0.81 (SD 0.32) and 0.87 mm (SD 0.32) at the implant shoulder and tip, respectively. No statistically significant differences were detected between the CT and CBCT groups (p = .169 and p = .551, p = .113 for angular and linear deviations, respectively). Implant placement via CT- or CBCT-derived mucosa-supported SLA guides yielded similar deviation values. Results should be confirmed on alternative CBCT scanners. © 2012 Wiley Periodicals, Inc.

  4. Internal consistency reliability and construct validity of the Dutch translation of the Francis Scale of Attitude toward Christianity among adolescents.

    Science.gov (United States)

    Francis, L J; Hermans, C A

    2000-02-01

    A sample of 1,021 young people attending Years 7, 8, 9, 10, and 11 at Catholic secondary schools within the state-maintained sector completed the Dutch translation of the Francis Scale of Attitude toward Christianity. The data support its reliability and validity and commend it for further use in studies conducted among young people in The Netherlands.

  5. Maintainability effectiveness evaluations and enhancement

    International Nuclear Information System (INIS)

    Seminara, J.L.

    1985-01-01

    In the mid-seventies EPRI initiated a research project to review the human factors aspects of nuclear power plant control rooms. In the course of investigating operator-control room interfaces in five operational control rooms, it became evident that many plant outages had either been caused or prolonged by human factors problems associated with maintenance activities. Consequently, as one of several follow-on projects, EPRI sponsored a review of nine power plants (five nuclear and four fossil) to examine the human factors aspects of plant maintainability. This survey revealed a wide variety of generic human factors problems that could negatively impact the effectiveness of plant maintenance personnel. It was clear that plant maintainability features deserved no less attention to human factors concerns than the operational features of the control room. This paper describes subsequent EPRI-initiated efforts to assist the utilities in conducting self-reviews of maintainability effectiveness and effect needed enhancements

  6. Maintenance optimization plan for essential equipment reliability

    International Nuclear Information System (INIS)

    Steffen, D.H.

    1996-02-01

    The Maintenance Optimization Plan (MOP) for Essential Equipment Reliability will furnish Tank Waste Remediation System (TWRS) management with a pro-active, forward-thinking process for maintaining essential structures, systems, and components (ESSC) at the Hanford Site tank farms in their designed condition, and to ensure optimum ESSC availability and reliability

  7. 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

  8. Human factors review of power plant maintainability

    International Nuclear Information System (INIS)

    Seminara, J.L.; Parsons, S.O.; Schmidt, W.J.; Gonzalez, W.R.; Dove, L.E.

    1980-10-01

    Human factors engineering is an interdisciplinary science and technology concerned with shaping the design of machines, facilities, and operational environments to promote safe, efficient, and reliable performance on the part of operators and maintainers of equipment systems. The human factors aspects of five nuclear power plants and four fossil fuel plants were evaluated using such methods as a checklist guided observation system, structured interviews with maintenance personnel, direct observations of maintenance tasks, reviews of procedures, and analyses of maintenance errors or accidents by means of the critical incident technique. The study revealed a wide variety of human factors problem areas, most of which are extensively photodocumented. The study recommends that a more systematic and formal approach be adopted to ensure that future power plants are human engineered to the needs of maintenance personnel

  9. 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.)

  10. Developing and maintaining nuclear competencies

    International Nuclear Information System (INIS)

    Gobert, C.

    2004-01-01

    The paper discusses the following aspects on the nuclear knowledge management: assimilation of knowledge management, recognition of the nuclear specificity, attracting young talents. Another feature which, possibly, differentiates nuclear from other high-tech industries is that time constraints in some nuclear development may very well exceed the duration of a generation of professionals. That means, not only maintaining scientific and technical knowledge, which, as a minimum, leads to maintain: a rigorous supervision of human resources in quality and quantity; anticipatory planning of human resources, with a special focus on succession planning concerning expertise positions; a steady and continuous effort in training and retraining programs. Maintaining the safety culture is also one of the major managerial duties. Taking full account of the nuclear specificity in knowledge maintenance and development in the AREVA group, requests a multifunctional approach, which combines efforts of Research and Innovation, and Human Resources departments, plus the group Nuclear inspectorate. It is acknowledged that the industry, basically, would readily rely on the capabilities of the academic world and research centers in ensuring that training and education in nuclear science and technologies are attuned to the evolving needs of the industry, in maintaining the proper educational programs and in fostering fruitful cooperations between them

  11. 76 FR 73608 - Reliability Technical Conference, North American Electric Reliability Corporation, Public Service...

    Science.gov (United States)

    2011-11-29

    ... or municipal authority play in forming your bulk power system reliability plans? b. Do you support..., North American Electric Reliability Corporation (NERC) Nick Akins, CEO of American Electric Power (AEP..., EL11-62-000] Reliability Technical Conference, North American Electric Reliability Corporation, Public...

  12. Guide to Operating and Maintaining EnergySmart Schools

    Energy Technology Data Exchange (ETDEWEB)

    None

    2010-01-01

    Through a commitment to high performance, school districts are discovering that smart energy choices can create lasting benefits for students, communities, and the environment. For example, an energy efficient school district with 4,000 students can save as much as $160,000 a year in energy costs. Over 10 years, those savings can reach $1.6 million, translating into the ability to hire more teachers, purchase more textbooks and computers, or invest in additional high performance facilities. Beyond these bottomline benefits, schools can better foster student health, decrease absenteeism, and serve as centers of community life. The U.S. Department of Energy's EnergySmart Schools Program promotes a 30 percent improvement in existing school energy use. It also encourages the building of new schools that exceed code (ASHRAE 90.11999) by 50 percent or more. The program provides resources like this Guide to Operating and Maintaining EnergySmart Schools to assist school decisionmakers in planning, financing, operating, and maintaining energy efficient, high performance schools. It also offers education and training for building industry professionals. Operations and maintenance refer to all scheduled and unscheduled actions for preventing equipment failure or decline with the goal of increasing efficiency, reliability, and safety. A preventative maintenance program is the organized and planned performance of maintenance activities in order to prevent system or production problems or failures from occurring. In contrast, deferred maintenance or reactive maintenance (also called diagnostic or corrective maintenance) is conducted to address an existing problem. This guide is a primary resource for developing and implementing a districtor schoolwide operations and maintenance (O&M) program that focuses on energy efficiency. The EnergySmart Schools Solutions companion CD contains additional supporting information for design, renovation, and retrofit projects. The objective

  13. Advanced remotely maintainable force-reflecting servomanipulator concept

    International Nuclear Information System (INIS)

    Kuban, D.P.; Martin, H.L.

    1984-01-01

    A remotely maintainable force-reflecting servomanipulator concept is being developed at the Oak Ridge National Laboratory as part of the Consolidated Fuel Reprocessing Program. This new manipulator addresses requirements of advanced nuclear fuel reprocessing with emphasis on force reflection, remote maintainability, reliability, radiation tolerance, and corrosion resistance. The advanced servomanipulator is uniquely subdivided into remotely replaceable modules which will permit in situ manipulator repair by spare module replacement. Manipulator modularization and increased reliability are accomplished through a force transmission system that uses gears and torque tubes. Digital control algorithms and mechanical precision are used to offset the increased backlash, friction, and inertia resulting from the gear drives. This results in the first remotely maintainable force-reflecting servomanipulator in the world. 10 references, 4 figures, 1 table

  14. 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

  15. Maintaining protein composition in cilia.

    Science.gov (United States)

    Stephen, Louise A; Elmaghloob, Yasmin; Ismail, Shehab

    2017-12-20

    The primary cilium is a sensory organelle that is vital in regulating several signalling pathways. Unlike most organelles cilia are open to the rest of the cell, not enclosed by membranes. The distinct protein composition is crucial to the function of cilia and many signalling proteins and receptors are specifically concentrated within distinct compartments. To maintain this composition, a mechanism is required to deliver proteins to the cilium whilst another must counter the entropic tendency of proteins to distribute throughout the cell. The combination of the two mechanisms should result in the concentration of ciliary proteins to the cilium. In this review we will look at different cellular mechanisms that play a role in maintaining the distinct composition of cilia, including regulation of ciliary access and trafficking of ciliary proteins to, from and within the cilium.

  16. Improving versus maintaining nuclear safety

    International Nuclear Information System (INIS)

    2002-01-01

    The concept of improving nuclear safety versus maintaining it has been discussed at a number of nuclear regulators meetings in recent years. National reports have indicated that there are philosophical differences between NEA member countries about whether their regulatory approaches require licensees to continuously improve nuclear safety or to continuously maintain it. It has been concluded that, while the actual level of safety achieved in all member countries is probably much the same, this is difficult to prove in a quantitative way. In practice, all regulatory approaches require improvements to be made to correct deficiencies and when otherwise warranted. Based on contributions from members of the NEA Committee on Nuclear Regulatory Activities (CNRA), this publication provides an overview of current nuclear regulatory philosophies and approaches, as well as insights into a selection of public perception issues. This publication's intended audience is primarily nuclear safety regulators, but government authorities, nuclear power plant operators and the general public may also be interested. (author)

  17. Maintaining US Space Weather Capabilities after DMSP: Research to Operations

    Science.gov (United States)

    Machuzak, J. S.; Gentile, L. C.; Burke, W. J.; Holeman, E. G.; Ober, D. M.; Wilson, G. R.

    2012-12-01

    The first Defense Meteorological Satellite Program (DMSP) spacecraft was launched in 1972; the last is scheduled to fly in 2020. Presently, there is no replacement for the space-weather monitoring sensors that now fly on DMSP. The present suite has provided comprehensive, long-term records that constitute a critical component of the US space weather corporate memory. Evolving operational needs and research accomplishments justify continued collection of space environmental data. Examples include measurements to: (1) Monitor the Dst index in real time as a driver of next-generation satellite drag models; (2) Quantify electromagnetic energy fluxes from deep space to the ionosphere/ thermosphere that heat neutrals, drive disturbance-dynamo winds and degrade precise orbit determinations; (3) Determine strengths of stormtime electric fields at high and low latitudes that lead to severe blackouts and spacecraft anomalies; (4) Specify variability of plasma density irregularities, equatorial plasma bubbles, and the Appleton anomaly to improve reliability of communication, navigation and surveillance links; (5) Characterize energetic particle fluxes responsible for auroral clutter and radar degradation; (6) Map regions of L-Band scintillation for robust GPS applications; and (7) Update the World Magnetic Field Model needed to maintain guidance system superiority. These examples illustrate the utility of continued space environment awareness. Comprehensive assessments of both operational requirements and research advances are needed to make informed selections of sensors and spacecraft that support future capabilities. A proposed sensor set and satellite constellation to provide the needed measurement capabilities will be presented.

  18. A comparative analysis of reliability, maintainability and availability for two alternatives of the production submarine systems: ANM and submarine ducts versus BOP and a subsea well testing tree; Analise comparativa da confiabilidade, mantenabilidade e disponibilidade para duas alternativas de sistemas submarino de producao: ANM e dutos submarinos versus BOP e arvore submarina de teste

    Energy Technology Data Exchange (ETDEWEB)

    Souza, Arlindo Antonio de; Polillo Filho, Adolfo; Santos, Otto Luiz Alcantara [PETROBRAS, Rio de Janeiro, RJ (Brazil)

    2004-07-01

    This technical article presents a study using the concepts of the Engineering of the Reliability and Risk Analysis with the objective of doing a comparative evaluation of the reliability of two alternative production systems for a marine well: one composed by a wet christmas tree (ANM) producing through underwater ducts (flow lines) and other, usually used in tests of long duration, using a subsea BOP and a subsea well testing tree (AST). The central point of the work was the evaluation of the probability of happening an event considered as critic, denominated 'critical flaw', during the well production life. The work uses one of the procedures and methodologies adopted in the Well Construction Engineering, GERISK, together with four computer applications for data treatment, generation of flaw distribution curves and times of repair, modelling and Monte Carlo simulations. The adopted strategy was the one of starting from the existent report, to assume an interval for the possible real value of the relevant parameters and then to establish the scenarios (more probable, optimist and pessimist). Based on those sceneries, the considered premises, the modelling and the reliabilities obtained for each one of the variables, the simulations have been made. As results, are presented the medium readiness, MTTFF (Mean Time To First Failure), the number of flaws and the expected costs. The work also displays the sensibility analysis in respect to the time of production of the well. (author)

  19. A comparative analysis of reliability, maintainability and availability for two alternatives of the production submarine systems: ANM and submarine ducts versus BOP and a subsea well testing tree; Analise comparativa da confiabilidade, mantenabilidade e disponibilidade para duas alternativas de sistemas submarino de producao: ANM e dutos submarinos versus BOP e arvore submarina de teste

    Energy Technology Data Exchange (ETDEWEB)

    Souza, Arlindo Antonio de; Polillo Filho, Adolfo; Santos, Otto Luiz Alcantara [PETROBRAS, Rio de Janeiro, RJ (Brazil)

    2004-07-01

    This technical article presents a study using the concepts of the Engineering of the Reliability and Risk Analysis with the objective of doing a comparative evaluation of the reliability of two alternative production systems for a marine well: one composed by a wet christmas tree (ANM) producing through underwater ducts (flow lines) and other, usually used in tests of long duration, using a subsea BOP and a subsea well testing tree (AST). The central point of the work was the evaluation of the probability of happening an event considered as critic, denominated 'critical flaw', during the well production life. The work uses one of the procedures and methodologies adopted in the Well Construction Engineering, GERISK, together with four computer applications for data treatment, generation of flaw distribution curves and times of repair, modelling and Monte Carlo simulations. The adopted strategy was the one of starting from the existent report, to assume an interval for the possible real value of the relevant parameters and then to establish the scenarios (more probable, optimist and pessimist). Based on those sceneries, the considered premises, the modelling and the reliabilities obtained for each one of the variables, the simulations have been made. As results, are presented the medium readiness, MTTFF (Mean Time To First Failure), the number of flaws and the expected costs. The work also displays the sensibility analysis in respect to the time of production of the well. (author)

  20. Maintaining High Challenge and High Support for Diverse Learners

    Science.gov (United States)

    Athanases, Steven

    2012-01-01

    As teachers, schools and school leaders work to better prepare California's culturally and linguistically diverse students, methods for doing so vary widely. One approach prioritizes safe spaces, welcoming environments, well-structured routines--school and classroom culture features essential for students' well-being. A second key priority, often…

  1. Maintaining the Fighting Force: Cohesion and Support Systems

    Science.gov (United States)

    1985-10-01

    underrepresented numbers (Kanter, 1977), external pressure to include a previously excluded group, and marginality resulting from minimal adaptation by the...Lots of individual performances yet some teamwork items - all working toward the final result. NEGATIVE Rugby Scrum - Massive confusion. Soccer

  2. 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...

  3. [How Reliable is Neuronavigation?].

    Science.gov (United States)

    Stieglitz, Lennart Henning

    2016-02-17

    Neuronavigation plays a central role in modern neurosurgery. It allows visualizing instruments and three-dimensional image data intraoperatively and supports spatial orientation. Thus it allows to reduce surgical risks and speed up complex surgical procedures. The growing availability and importance of neuronavigation makes clear how relevant it is to know about its reliability and accuracy. Different factors may influence the accuracy during the surgery unnoticed, misleading the surgeon. Besides the best possible optimization of the systems themselves, a good knowledge about its weaknesses is mandatory for every neurosurgeon.

  4. 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.

  5. Application of reliability methods in Ontario Hydro

    International Nuclear Information System (INIS)

    Jeppesen, R.; Ravishankar, T.J.

    1985-01-01

    Ontario Hydro have established a reliability program in support of its substantial nuclear program. Application of the reliability program to achieve both production and safety goals is described. The value of such a reliability program is evident in the record of Ontario Hydro's operating nuclear stations. The factors which have contributed to the success of the reliability program are identified as line management's commitment to reliability; selective and judicious application of reliability methods; establishing performance goals and monitoring the in-service performance; and collection, distribution, review and utilization of performance information to facilitate cost-effective achievement of goals and improvements. (orig.)

  6. Developing and maintaining instructor capabilities

    International Nuclear Information System (INIS)

    Flynn, W.P.; Smith, G.

    1985-01-01

    The New York Power Authority, after surveying available courses, decided to develop an in-house instructor training program. Following the principles of the Systems Approach to Training the course embodied the results of a job analysis resulting in a program containing instruction in Educational Philosophy, the Systems Approach to Training, Methods and Media, and Testing. The course content is covered through classroom instruction, on-the-job training, instructor evaluations, and assignments. Instructors completing the program continue to maintain skills with inservice training

  7. 76 FR 71011 - Reliability Technical Conference Agenda

    Science.gov (United States)

    2011-11-16

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

  8. Reliability of Circumplex Axes

    Directory of Open Access Journals (Sweden)

    Micha Strack

    2013-06-01

    Full Text Available We present a confirmatory factor analysis (CFA procedure for computing the reliability of circumplex axes. The tau-equivalent CFA variance decomposition model estimates five variance components: general factor, axes, scale-specificity, block-specificity, and item-specificity. Only the axes variance component is used for reliability estimation. We apply the model to six circumplex types and 13 instruments assessing interpersonal and motivational constructs—Interpersonal Adjective List (IAL, Interpersonal Adjective Scales (revised; IAS-R, Inventory of Interpersonal Problems (IIP, Impact Messages Inventory (IMI, Circumplex Scales of Interpersonal Values (CSIV, Support Action Scale Circumplex (SAS-C, Interaction Problems With Animals (IPI-A, Team Role Circle (TRC, Competing Values Leadership Instrument (CV-LI, Love Styles, Organizational Culture Assessment Instrument (OCAI, Customer Orientation Circle (COC, and System for Multi-Level Observation of Groups (behavioral adjectives; SYMLOG—in 17 German-speaking samples (29 subsamples, grouped by self-report, other report, and metaperception assessments. The general factor accounted for a proportion ranging from 1% to 48% of the item variance, the axes component for 2% to 30%; and scale specificity for 1% to 28%, respectively. Reliability estimates varied considerably from .13 to .92. An application of the Nunnally and Bernstein formula proposed by Markey, Markey, and Tinsley overestimated axes reliabilities in cases of large-scale specificities but otherwise works effectively. Contemporary circumplex evaluations such as Tracey’s RANDALL are sensitive to the ratio of the axes and scale-specificity components. In contrast, the proposed model isolates both components.

  9. Preventive maintenance and reliability-centered maintenance

    International Nuclear Information System (INIS)

    Anderson, J.G.

    1989-01-01

    In the recent past, the primary function of the preventive maintenance program at a nuclear power plant was to maintain the operability and reliability of the plant. Reducing overall maintenance costs by performing effective preventive maintenance, instead of more costly and disruptive corrective maintenance, instead of more costly and disruptive corrective maintenance, was a secondary consideration. In today's operating environment, the preventive maintenance program must meet the test of cost-effectiveness as well as many new standards for performance that are being required by rate regulators. The preventive maintenance program must be able to withstand the challenge of independent audit to a new standard of technical adequacy and compliance with recommendations from component vendors. In this new environment, the standard that is being applied at the San Onofre nuclear generating station (SONGS) is that the preventive maintenance program must meet the test of cost-effectiveness, improve equipment performance, support increased plant availability, and (a) literally implement the recommendations of the vendor, (b) provide other compensation for the vendor recommendation, or (c) provide technical justification for the deviation. The subject of this paper is the way that reliability-centered maintenance (RCM) is helping SONGS meet these challenges

  10. Maintaining consistency in distributed systems

    Science.gov (United States)

    Birman, Kenneth P.

    1991-01-01

    In systems designed as assemblies of independently developed components, concurrent access to data or data structures normally arises within individual programs, and is controlled using mutual exclusion constructs, such as semaphores and monitors. Where data is persistent and/or sets of operation are related to one another, transactions or linearizability may be more appropriate. Systems that incorporate cooperative styles of distributed execution often replicate or distribute data within groups of components. In these cases, group oriented consistency properties must be maintained, and tools based on the virtual synchrony execution model greatly simplify the task confronting an application developer. All three styles of distributed computing are likely to be seen in future systems - often, within the same application. This leads us to propose an integrated approach that permits applications that use virtual synchrony with concurrent objects that respect a linearizability constraint, and vice versa. Transactional subsystems are treated as a special case of linearizability.

  11. Compliance and High Reliability in a Complex Healthcare Organization.

    Science.gov (United States)

    Simon, Maxine dellaBadia

    2018-01-01

    When considering the impact of regulation on healthcare, visualize a spider's web. The spider weaves sections together to create the whole, with each fiber adding to the structure to support its success or lead to its failure. Each section is dependent on the others, and all must be aligned to maintain the structure. Outside forces can cause a shift in the web's fragile equilibrium.The interdependence of the sections of the spider's web is similar to the way hospital departments and services work together. An organization's structure must be shaped to support its mission and vision. At the same time, the business of healthcare requires the development and achievement of operational objectives and financial performance goals. Establishing a culture that is flexible enough to permit creativity, provide resiliency, and manage complexity as the organization grows is fundamental to success. An organization must address each of these factors while maintaining stability, carrying out its mission, and fostering improvement.Nature's order maintains the spider's web. Likewise, regulation can strengthen healthcare organizations by initiating disruptive changes that can support efforts to achieve and sustain high reliability in the delivery of care. To that end, leadership must be willing to provide the necessary vision and resources.

  12. Maintaining patients' dignity during clinical care: a qualitative interview study.

    Science.gov (United States)

    Lin, Yea-Pyng; Tsai, Yun-Fang

    2011-02-01

    This article is a report of a study undertaken to understand how nurses maintain patients' dignity in clinical practice. Dignity is a core concept in nursing care and maintaining patients' dignity is critical to their recovery. In Western countries, measures to maintain dignity in patients' care include maintaining privacy of the body, providing spatial privacy, giving sufficient time, treating patients as a whole person and allowing patients to have autonomy. However, this is an under-studied topic in Asian countries. For this qualitative descriptive study, data were collected in Taiwan in 2009 using in-depth interviews with a purposive sample of 30 nurses from a teaching hospital in eastern Taiwan. The audiotaped interviews were transcribed verbatim and analysed using content analysis. Nurses' measures to maintain dignity in patient care were captured in five themes: respect, protecting privacy, emotional support, treating all patients alike and maintaining body image. Participants did not mention beneficence, a crucial element achieved through the professional care of nurses that can enhance the recovery of patients. In-service education to help nurses enhance dignity in patient care should emphasize emotional support, maintaining body image and treating all patients alike. Our model for maintaining dignity in patient care could be used to develop a clinical care protocol for nurses to use in clinical practice. © 2010 Blackwell Publishing Ltd.

  13. Reliability issues : a Canadian perspective

    International Nuclear Information System (INIS)

    Konow, H.

    2004-01-01

    A Canadian perspective of power reliability issues was presented. Reliability depends on adequacy of supply and a framework for standards. The challenges facing the electric power industry include new demand, plant replacement and exports. It is expected that demand will by 670 TWh by 2020, with 205 TWh coming from new plants. Canada will require an investment of $150 billion to meet this demand and the need is comparable in the United States. As trade grows, the challenge becomes a continental issue and investment in the bi-national transmission grid will be essential. The 5 point plan of the Canadian Electricity Association is to: (1) establish an investment climate to ensure future electricity supply, (2) move government and industry towards smart and effective regulation, (3) work to ensure a sustainable future for the next generation, (4) foster innovation and accelerate skills development, and (5) build on the strengths of an integrated North American system to maximize opportunity for Canadians. The CEA's 7 measures that enhance North American reliability were listed with emphasis on its support for a self-governing international organization for developing and enforcing mandatory reliability standards. CEA also supports the creation of a binational Electric Reliability Organization (ERO) to identify and solve reliability issues in the context of a bi-national grid. tabs., figs

  14. 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.

  15. Emergency diesel generator reliability program

    International Nuclear Information System (INIS)

    Serkiz, A.W.

    1989-01-01

    The need for an emergency diesel generator (EDG) reliability program has been established by 10 CFR Part 50, Section 50.63, Loss of All Alternating Current Power, which requires that utilities assess their station blackout duration and recovery capability. EDGs are the principal emergency ac power sources for coping with a station blackout. Regulatory Guide 1.155, Station Blackout, identifies a need for (1) an EDG reliability equal to or greater than 0.95, and (2) an EDG reliability program to monitor and maintain the required levels. The resolution of Generic Safety Issue (GSI) B-56 embodies the identification of a suitable EDG reliability program structure, revision of pertinent regulatory guides and Tech Specs, and development of an Inspection Module. Resolution of B-56 is coupled to the resolution of Unresolved Safety Issue (USI) A-44, Station Blackout, which resulted in the station blackout rule, 10 CFR 50.63 and Regulatory Guide 1.155, Station Blackout. This paper discusses the principal elements of an EDG reliability program developed for resolving GSI B-56 and related matters

  16. 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.

  17. Computer Support for Conducting Supportability Trade-Offs in a Team Setting

    Science.gov (United States)

    1990-01-01

    with the ability of the product to be satisfactorily maintained throughout its intended useful life span with minimum expenditures of money and effort...during the pre-concept phase, thereby ensuring a reduction in cost due to reducing eventual retrofits, and a more supportable weapon system. Lauder ...It is shown that although large sums of money are expended on producing reliable components, these are vitiated if the end equipment is not exposed

  18. Building and maintaining media contacts

    International Nuclear Information System (INIS)

    Fenton, Bob

    2000-01-01

    This presentation is answering the question: 'how does British Energy build and maintain its relationships with journalists in so many areas', not only the basic industrial correspondents that you would expect to have to deal with an industry British Energy, but those dealing with science and technology, the environment, personnel and training, city and financial, political, and on and on, and that is just the national press. Then add the local and regional media around power station sites - literally hundreds of contacts and you start to get an idea about the size of our media contact database. But it is managed it rather well. Every six months British Energy takes part in a survey run by one of the UK's leading market research companies who conducts a poll among journalists and then rate each company's performance. In the last three years British Energy has not been outside the top five in most categories, and in the top two in several. The answer is a lot of work over a long period of time. You cannot expect to build trusting relationships with a journalist overnight. At British Energy the key is being open and honest, and always available. Of course good media relations is not a one-way street, and there has to be some element of compromise if you are to achieve a relationship based on mutual trust

  19. 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)

  20. Reliability analysis of stiff versus flexible piping

    International Nuclear Information System (INIS)

    Lu, S.C.

    1985-01-01

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

  1. Reliability data collection and use in risk and availability assessment

    International Nuclear Information System (INIS)

    Colombari, V.

    1989-01-01

    For EuReDatA it is a prevailing objective to initiate and support contact between experts, companies and institutions active in reliability engineering and research. Main topics of this 6th EuReDatA Conference are: Reliability data banks; incidents data banks; common cause data; source and propagation of uncertainties; computer aided risk analysis; reliability and incidents data acquisition and processing; human reliability; probabilistic safety and availability assessment; feedback of reliability into system design; data fusion; reliability modeling and techniques; structural and mechanical reliability; consequence modeling; software and electronic reliability; reliability tests. Some conference papers are separately indexed in the database. (HP)

  2. Neurophysiology underlying influence of stimulus reliability on audiovisual integration.

    Science.gov (United States)

    Shatzer, Hannah; Shen, Stanley; Kerlin, Jess R; Pitt, Mark A; Shahin, Antoine J

    2018-01-24

    We tested the predictions of the dynamic reweighting model (DRM) of audiovisual (AV) speech integration, which posits that spectrotemporally reliable (informative) AV speech stimuli induce a reweighting of processing from low-level to high-level auditory networks. This reweighting decreases sensitivity to acoustic onsets and in turn increases tolerance to AV onset asynchronies (AVOA). EEG was recorded while subjects watched videos of a speaker uttering trisyllabic nonwords that varied in spectrotemporal reliability and asynchrony of the visual and auditory inputs. Subjects judged the stimuli as in-sync or out-of-sync. Results showed that subjects exhibited greater AVOA tolerance for non-blurred than blurred visual speech and for less than more degraded acoustic speech. Increased AVOA tolerance was reflected in reduced amplitude of the P1-P2 auditory evoked potentials, a neurophysiological indication of reduced sensitivity to acoustic onsets and successful AV integration. There was also sustained visual alpha band (8-14 Hz) suppression (desynchronization) following acoustic speech onsets for non-blurred vs. blurred visual speech, consistent with continuous engagement of the visual system as the speech unfolds. The current findings suggest that increased spectrotemporal reliability of acoustic and visual speech promotes robust AV integration, partly by suppressing sensitivity to acoustic onsets, in support of the DRM's reweighting mechanism. Increased visual signal reliability also sustains the engagement of the visual system with the auditory system to maintain alignment of information across modalities. © 2018 Federation of European Neuroscience Societies and John Wiley & Sons Ltd.

  3. 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.

  4. Telecommunications system reliability engineering theory and practice

    CERN Document Server

    Ayers, Mark L

    2012-01-01

    "Increasing system complexity require new, more sophisticated tools for system modeling and metric calculation. Bringing the field up to date, this book provides telecommunications engineers with practical tools for analyzing, calculating, and reporting availability, reliability, and maintainability metrics. It gives the background in system reliability theory and covers in-depth applications in fiber optic networks, microwave networks, satellite networks, power systems, and facilities management. Computer programming tools for simulating the approaches presented, using the Matlab software suite, are also provided"

  5. 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.)

  6. Reliable design of electronic equipment an engineering guide

    CERN Document Server

    Natarajan, Dhanasekharan

    2014-01-01

    This book explains reliability techniques with examples from electronics design for the benefit of engineers. It presents the application of de-rating, FMEA, overstress analyses and reliability improvement tests for designing reliable electronic equipment. Adequate information is provided for designing computerized reliability database system to support the application of the techniques by designers. Pedantic terms and the associated mathematics of reliability engineering discipline are excluded for the benefit of comprehensiveness and practical applications. This book offers excellent support

  7. Challenges of designing fusion reactors for remote maintainability

    International Nuclear Information System (INIS)

    Mason, L.S.

    1981-01-01

    One of the major problems faced by the fusion community is the development of the high level of reliability required to assure that fusion will be a viable commercial power source. Much of the responsibility for solving this problem falls directly on the designer in developing concepts that have a high level of maintainability. The problems are both near-term, in developing maintainability for next generation engineering oriented reactors; and long range, in developing full maintainability for the more commercial concepts with their required high level of on-line time. The near-time challenge will include development of unqiue design concepts to perform inspection, maintenance, replacement, and testing under the stringent conditions imposed by the next generation engineering oriented machines. The long range challenge will focus on basic design concepts that will enable the full mainatability required by commerical fusion

  8. Load Control System Reliability

    Energy Technology Data Exchange (ETDEWEB)

    Trudnowski, Daniel [Montana Tech of the Univ. of Montana, Butte, MT (United States)

    2015-04-03

    This report summarizes the results of the Load Control System Reliability project (DOE Award DE-FC26-06NT42750). The original grant was awarded to Montana Tech April 2006. Follow-on DOE awards and expansions to the project scope occurred August 2007, January 2009, April 2011, and April 2013. In addition to the DOE monies, the project also consisted of matching funds from the states of Montana and Wyoming. Project participants included Montana Tech; the University of Wyoming; Montana State University; NorthWestern Energy, Inc., and MSE. Research focused on two areas: real-time power-system load control methodologies; and, power-system measurement-based stability-assessment operation and control tools. The majority of effort was focused on area 2. Results from the research includes: development of fundamental power-system dynamic concepts, control schemes, and signal-processing algorithms; many papers (including two prize papers) in leading journals and conferences and leadership of IEEE activities; one patent; participation in major actual-system testing in the western North American power system; prototype power-system operation and control software installed and tested at three major North American control centers; and, the incubation of a new commercial-grade operation and control software tool. Work under this grant certainly supported the DOE-OE goals in the area of “Real Time Grid Reliability Management.”

  9. Maintaining quality in blood banking.

    Science.gov (United States)

    Harvey, E; Hewison, C; Nevalainen, D E; Lloyd, H L

    1995-03-01

    component will warrant redress. The degree of fault attributed to the producer will in part depend on whether they have met the best available standards at all stages in the preparation of the product. If a Transfusion Service can show that it's operation has external accreditation, particularly to an internationally recognised standard such as ISO 9000 and they can show that staff have been properly trained, that equipment is properly supplied and maintained and that the facility is appropriate to the work being carried out, then the liability that exists when something goes wrong will be reduced.(ABSTRACT TRUNCATED AT 400 WORDS)

  10. Building and maintaining media relations

    International Nuclear Information System (INIS)

    Oesterberg, Anders

    2000-01-01

    Full text: In my opinion good media relations are among the most valuable investments regarding the communications and Public Relations operations within an Organisation. This means, that all the work you put up in building and maintaining media relations, is worth all the efforts. It can mean the difference between success or failure. Although a reporter never would admit that he or she is easily influenced, the fact is that you would get better press in an emergency case if you have a positive personal relation to the reporter. So, in my opinion there is nothing more important, in building and maintaining media relations, than the face-to-face-contact. My experience of good personal relations to reporters is also that you're not only getting better press in emergency cases. You are more successful in getting published when you have something positive to say, too. Honesty and openness are two key-words in this context. I have never tried to manipulate and delude a reporter, since that definitely would ruin the relationship. I always try to be as straight forward as possible and underline what I can say and what I can't. That instead of presenting some forced lies. For me, it is also very important to create some kind of mid-field ground, where the reporter and I can meet unprejudiced. Sense of humour and distance, both to yourself and your organisation, are two main characteristics that are invaluable in order to create a good personal relationship with a reporter. But, I'm very accurate in emphasizing when I enter my role as a company representative. All in order to be regarded as correct, yet obliging. To be quick when it comes to returning calls is another vital component that gives the reporter a feeling that he or she is important enough to be contacted as soon as possible. This service-minded attitude is of course good for the relationship. Besides the more personal relation it's important to have a business-like relation, where you show a great deal of

  11. Advanced digital technology - improving nuclear power plant performance through maintainability

    International Nuclear Information System (INIS)

    Ford, J.L.; Senechal, R.R.; Altenhein, G.D.; Harvey, R.P.

    1998-01-01

    In today's energy sector there is ever increasing pressure on utilities to operate power plants at high capacity factors. To ensure nuclear power is competitive into the next century, it is imperative that strategic design improvements be made to enhance the performance of nuclear power plants. There are a number of factors that affect a nuclear power plant's performance; lifetime maintenance is one of the major contributors. The maturing of digital technology has afforded ABB the opportunity to make significant design improvements in the area of maintainability. In keeping with ABB's evolutionary advanced nuclear plant design approach, digital technology has systematically been incorporated into the control and protection systems of the most recent Korean nuclear units in operation and under construction. One example of this was the multi-functional design team approach that was utilized for the development of ABB's Digital Plant Protection System (DPPS). The design team consisted of engineers, maintenance technicians, procurement specialists and manufacturing personnel in order to provide a complete perspective on all facets of the design. The governing design goals of increased reliability and safety, simplicity of design, use of off-the-shelf products and reduced need for periodic surveillance testing were met with the selection of proven ABB-Advant Programmable Logic Controllers (PLCs) as the heart of the DPPS. The application of digital PLC technology allows operation for extended periods without requiring routine maintenance or re-calibration. A well documented commercial dedication program approved by the United States Nuclear Regulatory Commission (US NRC) as part of the System 80+ TM Advanced Light Water Reactor Design Certification Program, allowed the use of off-the shelf products in the design of the safety protection system. In addition, a number of mechanical and electrical improvements were made which support maintainability. The result is a DPPS

  12. Fuel reliability experience in Finland

    International Nuclear Information System (INIS)

    Kekkonen, L.

    2015-01-01

    Four nuclear reactors have operated in Finland now for 35-38 years. The two VVER-440 units at Loviisa Nuclear Power Plant are operated by Fortum and two BWR’s in Olkiluoto are operated by Teollisuuden Voima Oyj (TVO). The fuel reliability experience of the four reactors operating currently in Finland has been very good and the fuel failure rates have been very low. Systematic inspection of spent fuel assemblies, and especially all failed assemblies, is a good practice that is employed in Finland in order to improve fuel reliability and operational safety. Investigation of the root cause of fuel failures is important in developing ways to prevent similar failures in the future. The operational and fuel reliability experience at the Loviisa Nuclear Power Plant has been reported also earlier in the international seminars on WWER Fuel Performance, Modelling and Experimental Support. In this paper the information on fuel reliability experience at Loviisa NPP is updated and also a short summary of the fuel reliability experience at Olkiluoto NPP is given. Keywords: VVER-440, fuel reliability, operational experience, poolside inspections, fuel failure identification. (author)

  13. Plans for Assessing Contractor Performance for the Camp Lemonnier Base Operations Support Contract Needed Improvement

    Science.gov (United States)

    2015-08-27

    electrical power such that all electrical requirements are continually met. 18. Wastewater : Operate and maintain the wastewater treatment plant and...supply—in our review. Roles and Responsibilities NAVFAC provides public works support for U.S. Naval shore installations around the world , and, as...Electrical: Operate and maintain the electrical power generation plant and distribution system to safely produce, transmit, and distribute reliable

  14. On the NPP structural reliability

    International Nuclear Information System (INIS)

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

    1980-01-01

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

  15. 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)

  16. Maintaining and improving the control and safety systems for the Electromagnetic Calorimeter of the CMS experiment

    CERN Document Server

    Di Calafiori, Diogo Raphael; Dissertori, Günther; Holme, Oliver; Jovanovic, Dragoslav; Lustermann, Werner; Zelepoukine, Serguei

    2012-01-01

    This paper presents the current architecture of the control and safety systems designed and implemented for the Electromagnetic Calorimeter (ECAL) of the Compact Muon Solenoid (CMS) experiment at the Large Hadron Collider (LHC). An evaluation of system performance during all CMS physics data taking periods is reported, with emphasis on how software and hardware solutions are used to overcome limitations, whilst maintaining and improving reliability and robustness. The outcomes of the CMS ECAL Detector Control System (DCS) Software Analysis Project were a fundamental step towards the integration of all control system applications and the consequent piece-by-piece software improvements allowed a smooth transition to the latest revision of the system. The ongoing task of keeping the system in-line with new hardware technologies and software platforms specified by the CMS DCS Group is discussed. The structure of the comprehensive support service with detailed incident logging is presented in addition to a complet...

  17. Exploitation examination of reliability of coal dust systems

    International Nuclear Information System (INIS)

    Dojchinovski, Ilija; Trajkovski, Kole

    1997-01-01

    Designers and operators wish is, long, failure free operation at designed parameters of every system. Always we know the system start up time, but we don't know how long this system will operate successfully. Because of that in this article is given a method how, step by step, to determine the reliability of the system. Reliability parameters are obtained from experimental and operational data. When reliability parameters are determined then it is very easy to compare reliability of similar systems, for example excavators, or different systems, such as truck and rubber band transport system. Practical use of the theory of reliability is by purchasing of the systems when manufacturers have to have and present reliability parameters and on this way we can decide which system satisfies our needs regarding the quality-price-reliability. Reliability can be practically used in system operation where: 1) system reliability is maintained with proper start, use and shutdown of the system; 2) a system reliability is maintained with good maintenance organization; 3) a system reliability is maintained with innovations and improvements with final purpose removing of the imperfections experienced through the operation. Reliability is very important parameter in power generation plants. (Author)

  18. 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.

  19. A reliability program approach to operational safety

    International Nuclear Information System (INIS)

    Mueller, C.J.; Bezella, W.A.

    1985-01-01

    A Reliability Program (RP) model based on proven reliability techniques is being formulated for potential application in the nuclear power industry. Methods employed under NASA and military direction, commercial airline and related FAA programs were surveyed and a review of current nuclear risk-dominant issues conducted. The need for a reliability approach to address dependent system failures, operating and emergency procedures and human performance, and develop a plant-specific performance data base for safety decision making is demonstrated. Current research has concentrated on developing a Reliability Program approach for the operating phase of a nuclear plant's lifecycle. The approach incorporates performance monitoring and evaluation activities with dedicated tasks that integrate these activities with operation, surveillance, and maintenance of the plant. The detection, root-cause evaluation and before-the-fact correction of incipient or actual systems failures as a mechanism for maintaining plant safety is a major objective of the Reliability Program. (orig./HP)

  20. Reliability tasks from prediction to field use

    International Nuclear Information System (INIS)

    Guyot, Christian.

    1975-01-01

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

  1. 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.

  2. 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.

  3. 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

  4. 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?

  5. 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

  6. 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....

  7. 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.)

  8. The reliability of integrated gasification combined cycle (IGCC) power generation units

    Energy Technology Data Exchange (ETDEWEB)

    Higman, C.; DellaVilla, S.; Steele, B. [Syngas Consultants Ltd. (United Kingdom)

    2006-07-01

    This paper presents two interlinked projects aimed at supporting the improvement of integrated gasification combined cycle (IGCC) reliability. The one project comprises the extension of SPS's existing ORAP (Operational Reliability Analysis Program) reliability, availability and maintainability (RAM) tracking technology from its existing base in natural gas open and combined cycle operations into IGCC. The other project is using the extended ORAP database to evaluate performance data from existing plants. The initial work has concentrated on evaluating public domain data on the performance of gasification based power and chemical plants. This is being followed up by plant interviews in some 20 plants to verify and expand the database on current performance. 23 refs., 8 figs., 2 tabs.

  9. The importance of maintainability in maintenance cost management

    International Nuclear Information System (INIS)

    Allen, R.R.

    1996-01-01

    This paper provides specific examples and results from ongoing projects at Power Plants, and for offshore oil platforms. The paper describes the vital role maintainability has on plant availability. How the application of equipment maintainability principles, if addressed using state of the art computer tools and advanced business processes can bring annual return on investment results as high as 15 to 1. The maintenance process of today and for the future must provide for high plant availability at the lowest possible cost. The high cost of obtaining equipment reliability levels necessary to meet required availability demands has not proved to be sustainable. Therefore new business decision processes that address equipment failures as part of the maintenance process have been developed. Repair costs require that equipment failures be selective and controlled so that a high level of safety and plant availability is assurance. This can only be accomplished by the use of advanced computer tools in the hands of well trained maintenance-engineering specialist. The relationship between Reliability Centered Maintenance (RCM), Condition Directed Planned Maintenance (CDPM), and maintainability is also presented

  10. Winning public and political support for nuclear

    International Nuclear Information System (INIS)

    McFadden, D.J.

    2006-01-01

    The nuclear industry is entering an historic battle for the hearts and minds of Canadians as government decides on nuclear new build. Recent polls indicate that public support is rising for nuclear power. However, the support could be eroded by negative events or intense lobbying by anti-nuclear groups. The nuclear industry must deal with concerns raised about nuclear power, such as cost, safety, reliability and waste. The nuclear industry should build upon the positive movement in public support. The industry must go to Canadians with a credible message which responds effectively to public concerns. It must be remembered that winning public support will be essential to winning and maintaining political support. (author)

  11. Winning public and political support for nuclear

    Energy Technology Data Exchange (ETDEWEB)

    McFadden, D.J. [Gowling LaFleur Henderson, LLP, Toronto, Ontario (Canada)

    2006-07-01

    The nuclear industry is entering an historic battle for the hearts and minds of Canadians as government decides on nuclear new build. Recent polls indicate that public support is rising for nuclear power. However, the support could be eroded by negative events or intense lobbying by anti-nuclear groups. The nuclear industry must deal with concerns raised about nuclear power, such as cost, safety, reliability and waste. The nuclear industry should build upon the positive movement in public support. The industry must go to Canadians with a credible message which responds effectively to public concerns. It must be remembered that winning public support will be essential to winning and maintaining political support. (author)

  12. 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.

  13. Sponsored Grant-maintained Schools: Extending the Franchise?

    Science.gov (United States)

    Walford, Geoffrey

    1997-01-01

    Discusses the introduction and implementation of the 1988 Education Reform Act for England and Wales. Traces the attempts of several existing private schools to become grant maintained (eligible for various forms of government support). Most private and faith-based schools have not been successful in this endeavor. Discusses the reasons for this.…

  14. Impact of Agile Software Development Model on Software Maintainability

    Science.gov (United States)

    Gawali, Ajay R.

    2012-01-01

    Software maintenance and support costs account for up to 60% of the overall software life cycle cost and often burdens tightly budgeted information technology (IT) organizations. Agile software development approach delivers business value early, but implications on software maintainability are still unknown. The purpose of this quantitative study…

  15. Maintaining Scholarly Standards in Feminist Literature

    Directory of Open Access Journals (Sweden)

    Allen Esterson

    2013-03-01

    Full Text Available In the editorial Introduction to Women, Science, and Technology: A Reader in Feminist Science Studies, published in 2001, can be found the exemplary statement that among the norms for acquiring scientific knowledge is “skepticism (all claims should be scrutinized for errors”. In this article, I address a section relating to historical contentions in the same volume that, I argue, fails to live up to this basic standard of scholarly research. It is now quite widely believed that Mileva Marić, Einstein’s first wife, played an active role in Einstein’s early scientific work until well after they married in 1903. Some commentators go so far as to argue that she coauthored his three major 1905 papers, while others contend that she solved the mathematical problems for him. I examine the claims made in relation to Marić in the section in question in the above-cited volume, and investigate the sources of the evidential claims that have been adduced to support them. I conclude that the several claims are without reliable evidential bases.

  16. Maintaining Gamma Spectrometer and its challenges

    International Nuclear Information System (INIS)

    Mazlipah Mohd Ramlan; Ramzah Mohamed; Saipo Bahari Abdul Ratan

    2011-01-01

    This paper discusses the activities of the Group Maintenance of Instrumentation and Automation Center. Maintenance of group activities is to provide maintenance service on equipment at the Malaysian Nuclear Agency. Category of equipment is maintained instrumentation / nuclear electronics, scientific, analytical, security, communications, audio visual and other related. Maintenance services is to support research and development and scientific services at Nuclear Malaysia. Equipment maintenance services including repair service (CM), periodic maintenance (PM), technical testing and calibration of new devices. The objective is to ensure that maintenance activities can be the hope of an equipment, extend the life of the operation of the equipment, reducing 'down time' and reduce maintenance costs. Among the challenges in managing the maintenance of equipment in Nuclear Malaysia is the lack of expertise in specific areas such as nuclear instrumentation, analytical instruments, the problem of the inability of local suppliers to provide after-sales service, lack of spares, maintenance and nothing less emphasis on preventive maintenance schedule is perfect. (author)

  17. Reliability engineering theory and practice

    CERN Document Server

    Birolini, Alessandro

    2017-01-01

    This book shows how to build in and assess reliability, availability, maintainability, and safety (RAMS) of components, equipment, and systems. It presents the state of the art of reliability (RAMS) engineering, in theory & practice, and is based on over 30 years author's experience in this field, half in industry and half as Professor of Reliability Engineering at the ETH, Zurich. The book structure allows rapid access to practical results. Methods & tools are given in a way that they can be tailored to cover different RAMS requirement levels. Thanks to Appendices A6 - A8 the book is mathematically self-contained, and can be used as a textbook or as a desktop reference with a large number of tables (60), figures (210), and examples / exercises^ 10,000 per year since 2013) were the motivation for this final edition, the 13th since 1985, including German editions. Extended and carefully reviewed to improve accuracy, it represents the continuous improvement effort to satisfy reader's needs and confidenc...

  18. Operator reliability assessment system (OPERAS)

    International Nuclear Information System (INIS)

    Singh, A.; Spurgin, A.J.; Martin, T.; Welsch, J.; Hallam, J.W.

    1991-01-01

    OPERAS is a personal-computer (PC) based software to collect and process simulator data on control-room operators responses during requalification training scenarios. The data collection scheme is based upon approach developed earlier during the EPRI Operator Reliability Experiments project. The software allows automated data collection from simulator, thus minimizing simulator staff time and resources to collect, maintain and process data which can be useful in monitoring, assessing and enhancing the progress of crew reliability and effectiveness. The system is designed to provide the data and output information in the form of user-friendly charts, tables and figures for use by plant staff. OPERAS prototype software has been implemented at the Diablo Canyon (PWR) and Millstone (BWR) plants and is currently being used to collect operator response data. Data collected from similator include plant-state variables such as reactor pressure and temperature, malfunction, times at which annunciators are activated, operator actions and observations of crew behavior by training staff. The data and systematic analytical results provided by the OPERAS system can contribute to increase objectivity by the utility probabilistic risk analysis (PRA) and training staff in monitoring and assessing reliability of their crews

  19. An Adaptive Classification Strategy for Reliable Locomotion Mode Recognition

    Directory of Open Access Journals (Sweden)

    Ming Liu

    2017-09-01

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

  20. 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

  1. Evolution of maintainability in France since 1971

    International Nuclear Information System (INIS)

    Guyot, Christian.

    1975-01-01

    The purpose of the paper is to make the point of maintainability in France since 1971. The importance of maintainability is recalled. Publications in France from 1971 to 1975 show the interest arose by maintainability; their analysis permits to make clear the general plan followed by the studies and gives indications on the directions of actual efforts. Conclusion is drawn on the orientation of work at short, medium and long term [fr

  2. Space maintainers in dentistry: past to present.

    Science.gov (United States)

    Setia, Vikas; Pandit, Inder Kumar; Srivastava, Nikhil; Gugnani, Neeraj; Sekhon, Harveen Kaur

    2013-10-01

    Early orthodontic interventions are often initiated in the developing dentition to promote favourable developmental changes. Interceptive orthodontic can eliminate or reduce the severity of a developing malocclusion, the complexity of orthodontic treatment, overall treatment time and cost. The safest way to prevent future malocclusions from tooth loss is to place a space maintainer that is effective and durable. An appropriate use of space maintainer is advocated to hold the space until the eruption of permanent teeth. This case report describes the various changing trends in use of space maintainers: conventional band and loop, prefabricated band with custom made loop and glass fibre reinforced composite resins as space maintainers.

  3. 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...

  4. Exploration of reliability databases and comparison of former IFMIF's results

    International Nuclear Information System (INIS)

    Tapia, Carlos; Dies, Javier; Abal, Javier; Ibarra, Angel; Arroyo, Jose M.

    2011-01-01

    There is an uncertainty issue about the applicability of industrial databases to new designs, such as the International Fusion Materials Irradiation Facility (IFMIF), as they usually contain elements for which no historical statistics exist. The exploration of common components reliability data in Accelerator Driven Systems (ADS) and Liquid Metal Technologies (LMT) frameworks is the milestone to analyze the data used in IFMIF reliability's reports and for future studies. The comparison between the reliability accelerator results given in the former IFMIF's reports and the databases explored has been made by means of a new accelerator Reliability, Availability, Maintainability (RAM) analysis. The reliability database used in this analysis is traceable.

  5. Phased mission analysis of maintained systems: a study in reliability risk analysis

    International Nuclear Information System (INIS)

    Terpstra, K.

    1984-01-01

    The present study develops a general theory that treats the probability of occurrence of each branch of an event tree and that takes correctly into account the dependencies between systems; incorporates within the general theory the solution of the problem of phased mission analysis. It also includes the general model components, that may or may not be repairable, with general lifetime and repairtime distribution, i.e. in the model repairable systems should be taken into account. Finally a computer program is developed that is based on this general theory, i.e. a computer program that is able to perform fully the probabilistic calculations of a risk analysis and that can handle in a correct way phased mission analysis of repairable systems. The theory is applied to a boiling water reactor accident. (Auth.)

  6. System Verification Through Reliability, Availability, Maintainability (RAM) Analysis & Technology Readiness Levels (TRLs)

    Energy Technology Data Exchange (ETDEWEB)

    Emmanuel Ohene Opare, Jr.; Charles V. Park

    2011-06-01

    The Next Generation Nuclear Plant (NGNP) Project, managed by the Idaho National Laboratory (INL), is authored by the Energy Policy Act of 2005, to research, develop, design, construct, and operate a prototype fourth generation nuclear reactor to meet the needs of the 21st Century. A section in this document proposes that the NGNP will provide heat for process heat applications. As with all large projects developing and deploying new technologies, the NGNP is expected to meet high performance and availability targets relative to current state of the art systems and technology. One requirement for the NGNP is to provide heat for the generation of hydrogen for large scale productions and this process heat application is required to be at least 90% or more available relative to other technologies currently on the market. To reach this goal, a RAM Roadmap was developed highlighting the actions to be taken to ensure that various milestones in system development and maturation concurrently meet required availability requirements. Integral to the RAM Roadmap was the use of a RAM analytical/simulation tool which was used to estimate the availability of the system when deployed based on current design configuration and the maturation level of the system.

  7. Maintained ship hull girder ultimate strength reliability considering corrosion and fatigue

    DEFF Research Database (Denmark)

    Hu, Yong; Cui, W.; Pedersen, Preben Terndrup

    2004-01-01

    The prupose of this paper is to propose a methodology to assess the time-variant ultimate strength of ship hull girder under the degradations of corrosion and fatigue. The effects of fatigue cracks on the tensile and compressive residual ultimate strength of stiffened panels and unstiffened plates......, webs and flanges, respectively. The effects of inspections and repair are taken into account. A minimum net thickness rule is used to determine repair policies. A procedure is proposed to determine the maximum allowable corrosion thickness of different parts of the hull cross section. The procedure...

  8. Confidence Intervals for System Reliability and Availability of Maintained Systems Using Monte Carlo Techniques

    Science.gov (United States)

    1981-12-01

    DTIC _JUN ,I 51982 UNITED STATES AIR FORCE AIR UNIVERSITY E AIR FORCE INSTITUTE OF TECHNOLOGY Wright-Patterson Air-force Base,Ohio S 2 B 14 Best...t’re Air F:or- e -ns"it’.,, e of Technclogy Air Uv-ýerz.tyj in Partial 𔄁ulfilIThent Reýquirements fol- ,-hth D,ýýr.e c4" MastLer of’ OperaZ-ins...iesearc- VeTA 3 MohamedO ’’’’Jo SpD’ Fas.abal-la Lt. C ol. Egyplt.’.an Army Gradua~’p ( ler ons Research December 1981 Approcved fL~r pu>ý’ rclea.se

  9. Facility Reliability and Maintainability: An Investigation of the Air Force Civil Engineering Recurring Work Program

    Science.gov (United States)

    1989-09-01

    18:2). A recent survey by the Strategic Air Command (SAC) Mechanical Fquipment Management Evaluation Team ( MEMET ) determined that equipment was...identified by MEMET included Maintenance Action Sheets (MAS) that reported work which was not completed, and other MAS which annotated recurring work...readily apparent. Problem Military. The Deputy Chief of Staff for Engineering and Services, HQ SAC, established the MEMET in 1984 in response to a

  10. Advanced Monitoring to Improve Combustion Turbine/Combined Cycle Reliability, Availability & Maintainability

    Energy Technology Data Exchange (ETDEWEB)

    Leonard Angello

    2005-09-30

    Power generators are concerned with the maintenance costs associated with the advanced turbines that they are purchasing. Since these machines do not have fully established Operation and Maintenance (O&M) track records, power generators face financial risk due to uncertain future maintenance costs. This risk is of particular concern, as the electricity industry transitions to a competitive business environment in which unexpected O&M costs cannot be passed through to consumers. These concerns have accelerated the need for intelligent software-based diagnostic systems that can monitor the health of a combustion turbine in real time and provide valuable information on the machine's performance to its owner/operators. EPRI, Impact Technologies, Boyce Engineering, and Progress Energy have teamed to develop a suite of intelligent software tools integrated with a diagnostic monitoring platform that, in real time, interpret data to assess the 'total health' of combustion turbines. The 'Combustion Turbine Health Management System' (CTHMS) will consist of a series of 'Dynamic Link Library' (DLL) programs residing on a diagnostic monitoring platform that accepts turbine health data from existing monitoring instrumentation. CTHMS interprets sensor and instrument outputs, correlates them to a machine's condition, provide interpretative analyses, project servicing intervals, and estimate remaining component life. In addition, the CTHMS enables real-time anomaly detection and diagnostics of performance and mechanical faults, enabling power producers to more accurately predict critical component remaining useful life and turbine degradation.

  11. Modernizing and Maintaining Instrumentation and Control Systems in Nuclear Power Plants

    International Nuclear Information System (INIS)

    Naser, Joseph; Torok, Raymond; Shankar, Ramesh

    2003-01-01

    Deregulation of the electric utilities has made a major impact on nuclear power plants. To be competitive, more emphasis is being put on cost-effective production of electricity with a more critical look at whether a system should be modernized due to obsolescence, reliability, or productivity concerns. Instrumentation and control (I and C) systems play an important role in reducing the cost of producing electricity while maintaining or enhancing safety. Systems that are well designed, reliable, enhance productivity, and are cost-effective to operate and maintain can reduce the overall costs. Modern technology with its ability to better provide and use real-time information offers an effective platform for modernizing systems. At the same time, new technology brings new challenges and issues, especially for safety systems in nuclear power plants. To increase competitiveness, it is important to take advantage of the opportunities offered by modern technology and to address the new challenges and issues in a cost-effective manner. The Electric Power Research Institute (EPRI) and its member utilities have been working together with other members of the nuclear industry since 1990 to address I and C modernization and maintenance issues. The EPRI I and C Program has developed a life-cycle management approach for I and C systems that involves the optimization of maintenance, monitoring, and capital resources to sustain safety and performance throughout the plant life. Strategic planning methodologies and implementation guidelines addressing digital I and C issues in nuclear power plants have been developed. Work is ongoing in diverse areas to support the design, implementation, and operation of new digital systems. Technology transfer is an integral part of this I and C program

  12. 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

  13. 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)

  14. Structural Reliability Analysis of Wind Turbines: A Review

    Directory of Open Access Journals (Sweden)

    Zhiyu Jiang

    2017-12-01

    Full Text Available The paper presents a detailed review of the state-of-the-art research activities on structural reliability analysis of wind turbines between the 1990s and 2017. We describe the reliability methods including the first- and second-order reliability methods and the simulation reliability methods and show the procedure for and application areas of structural reliability analysis of wind turbines. Further, we critically review the various structural reliability studies on rotor blades, bottom-fixed support structures, floating systems and mechanical and electrical components. Finally, future applications of structural reliability methods to wind turbine designs are discussed.

  15. 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.

  16. Stochastic models in reliability and maintenance

    CERN Document Server

    2002-01-01

    Our daily lives can be maintained by the high-technology systems. Computer systems are typical examples of such systems. We can enjoy our modern lives by using many computer systems. Much more importantly, we have to maintain such systems without failure, but cannot predict when such systems will fail and how to fix such systems without delay. A stochastic process is a set of outcomes of a random experiment indexed by time, and is one of the key tools needed to analyze the future behavior quantitatively. Reliability and maintainability technologies are of great interest and importance to the maintenance of such systems. Many mathematical models have been and will be proposed to describe reliability and maintainability systems by using the stochastic processes. The theme of this book is "Stochastic Models in Reliability and Main­ tainability. " This book consists of 12 chapters on the theme above from the different viewpoints of stochastic modeling. Chapter 1 is devoted to "Renewal Processes," under which cla...

  17. The Cost of Maintaining Educational Communications Equipment.

    Science.gov (United States)

    Humphrey, David A.

    Tentative formulas for calculating the cost of maintaining educational communications equipment are proposed. The formulas are based on a survey of campuses of the State University of New York. The survey analyzed the types of equipment to be maintained, types of maintenance, who uses the equipment, who services the equipment, and the cost…

  18. Mission Reliability Estimation for Repairable Robot Teams

    Science.gov (United States)

    Trebi-Ollennu, Ashitey; Dolan, John; Stancliff, Stephen

    2010-01-01

    A mission reliability estimation method has been designed to translate mission requirements into choices of robot modules in order to configure a multi-robot team to have high reliability at minimal cost. In order to build cost-effective robot teams for long-term missions, one must be able to compare alternative design paradigms in a principled way by comparing the reliability of different robot models and robot team configurations. Core modules have been created including: a probabilistic module with reliability-cost characteristics, a method for combining the characteristics of multiple modules to determine an overall reliability-cost characteristic, and a method for the generation of legitimate module combinations based on mission specifications and the selection of the best of the resulting combinations from a cost-reliability standpoint. The developed methodology can be used to predict the probability of a mission being completed, given information about the components used to build the robots, as well as information about the mission tasks. In the research for this innovation, sample robot missions were examined and compared to the performance of robot teams with different numbers of robots and different numbers of spare components. Data that a mission designer would need was factored in, such as whether it would be better to have a spare robot versus an equivalent number of spare parts, or if mission cost can be reduced while maintaining reliability using spares. This analytical model was applied to an example robot mission, examining the cost-reliability tradeoffs among different team configurations. Particularly scrutinized were teams using either redundancy (spare robots) or repairability (spare components). Using conservative estimates of the cost-reliability relationship, results show that it is possible to significantly reduce the cost of a robotic mission by using cheaper, lower-reliability components and providing spares. This suggests that the

  19. 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.

  20. 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.

  1. 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.

  2. 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

  3. 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...

  4. 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...

  5. 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

  6. 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.

  7. Mechanical development for reliable reactor components

    International Nuclear Information System (INIS)

    Ross-Ross, P.A.; Metcalfe, R.

    1983-09-01

    The CANDU reactor has achieved worldwide distinction because of its reliable performance. To achieve this, special attention was given to the reliability and maintainability of components in the heavy water circuits. Development programs were initiated early in the history of the CANDU reactor to improve the effectiveness of pump seals, valves, and static seals because of unacceptable performance of the commercial equipment then available. As a result, pump seals with a five year life now appear achievable, and valves and static seals are no longer a significant concern in CANDU reactors. Increasing effort is being given remotely operated tools and fabrication systems for radioactive environments

  8. Reliability and Utility of the Behaviour Support Plan Quality Evaluation Tool (BSP-QEII) for Auditing and Quality Development in Services for Adults with Intellectual Disability and Challenging Behaviour

    Science.gov (United States)

    McVilly, K.; Webber, L.; Paris, M.; Sharp, G.

    2013-01-01

    Background: Having an objective means of evaluating the quality of behaviour support plans (BSPs) could assist service providers and statutory authorities to monitor and improve the quality of support provided to people with intellectual disability (ID) who exhibit challenging behaviour. The Behaviour Support Plan Quality Evaluation Guide II…

  9. A Vision for Spaceflight Reliability: NASA's Objectives Based Strategy

    Science.gov (United States)

    Groen, Frank; Evans, John; Hall, Tony

    2015-01-01

    In defining the direction for a new Reliability and Maintainability standard, OSMA has extracted the essential objectives that our programs need, to undertake a reliable mission. These objectives have been structured to lead mission planning through construction of an objective hierarchy, which defines the critical approaches for achieving high reliability and maintainability (R M). Creating a hierarchy, as a basis for assurance implementation, is a proven approach; yet, it holds the opportunity to enable new directions, as NASA moves forward in tackling the challenges of space exploration.

  10. Risk and reliability allocation to risk control

    International Nuclear Information System (INIS)

    Vojnovic, D.; Kozuh, M.

    1992-01-01

    The risk allocation procedure is used as an analytical model to support the optimal decision making for reliability/availability improvement planning. Both levels of decision criteria, the plant risk measures and plant performance indices, are used in risk allocation procedure. Decision support system uses the multi objective decision making concept. (author) [sl

  11. Managing relationships between electric power industry restructuring and grid reliability

    International Nuclear Information System (INIS)

    Thomas, R.J.

    2005-01-01

    The electricity system is a critical infrastructure, and its continued and reliable functioning is essential to the nation's economy and well-being. However, the inter-dependency of electricity networks is not completely understood. The economic impact of outages was discussed in this white paper. It was suggested that moving to a restructured environment has degraded the reliability of the bulk system. New institutional arrangements and approaches to information management are needed. It was suggested that reliability practices caused the 2003 blackout, and not technical failures. Uncertainties in the restructured market were discussed, as well as incentives to maintain system adequacy. Examples of deregulation in other countries were presented. Organizational complexities were reviewed, including the Federal Energy Regulatory Commission's (FERC) requirements and the new layers of complexity that have been added to the decision-making process in the light of restructuring. Planning and connectivity issues were reviewed. The need for design standards in power grid control centres was discussed. Difficulties in collecting data from different control centres were considered. Issues concerning the lack of investment in research and development were discussed, with particular reference to the urgent need for coordinated research programs. The looming manpower crisis in the electric power industry was also discussed. Recommendations included ensuring that the transmission system can support a market structure; building a national reliability centre; solving the manpower crisis; and testing market designs before deploying them. It was concluded that good engineering design principles, including experimental economic testing, should be required of any new electricity market design before authorizing its use. 31 refs., 1 tab., 6 figs

  12. The advantages of reliability centered maintenance for standby safety systems

    International Nuclear Information System (INIS)

    Dam, R.F.; Ayazzudin, S.; Nickerson, J.H.; DeLong, A.I.

    2002-01-01

    Full text: On standby safety systems, nuclear plants have to balance the requirements of demonstrating the reliability of each system, while maintaining the system and plant availability. With the goal of demonstrating statistical reliability, these systems have extensive testing programs, which often makes the system unavailable and this can impact the plant capacity. The inputs to the process are often safety and regulatory related, resulting in programs that provide a high level of scrutiny on the systems being considered. In such cases, the value of the application of a maintenance optimization strategy, such as Reliability Centered Maintenance (RCM), is questioned. Part of the question stems from the use of the word 'Reliability' in RCM, which implies a level of redundancy when applied to a system maintenance program driven by reliability requirements. A deeper look at the RCM process, however, shows that RCM has the goal of ensuring that the system operates 'reliably' through the application of an integrated maintenance strategy. This is a subtle, but important distinction. Although the system reliability requirements are an important part of the strategy evaluation, RCM provides a broader context where testing is only one part of an overall strategy focused on ensuring that component function is maintained through a combination of monitoring technologies (including testing), predictive techniques, and intrusive maintenance strategies. Each strategy is targeted to identify known component degradation mechanisms. The conclusion is that a maintenance program driven by reliability requirements will tend to have testing defined at a frequency intended to support the needed statistics. The testing demonstrates that the desired function is available today. Maintenance driven by functional requirements and known failure causes, as developed through an RCM assessment, will have frequencies tied to industry experience with components and rely on a higher degree of

  13. The new Space Shuttle Transportation System (STS) - Problem, performance, supportability, and programmatic trending program

    Science.gov (United States)

    Crawford, J. L.; Rodney, G. A.

    1989-01-01

    This paper describes the NASA Space Shuttle Trend Analysis program. The four main areas of the program - problem/reliability, performance, supportability, and programmatic trending - are defined, along with motivation for these areas, the statistical methods used, and illustrative Space Shuttle applications. Also described is the NASA Safety, Reliability, Maintainability and Quality Assurance (SRM&QA) Management Information Center, used to focus management attention on key near-term launch concerns and long-range mission trend issues. Finally, the computer data bases used to support the program and future program enhancements are discussed.

  14. Classifier Fusion With Contextual Reliability Evaluation.

    Science.gov (United States)

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

    2018-05-01

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

  15. Coastal Maintained Channels in US waters

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This layer shows coastal channels and waterways that are maintained and surveyed by the U.S. Army Corps of Engineers (USACE). These channels are necessary...

  16. Marshal: Maintaining Evolving Models, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — SIFT proposes to design and develop the Marshal system, a mixed-initiative tool for maintaining task models over the course of evolving missions. Marshal-enabled...

  17. 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

  18. 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....

  19. RTE - 2013 Reliability Report

    International Nuclear Information System (INIS)

    Denis, Anne-Marie

    2014-01-01

    RTE publishes a yearly reliability report based on a standard model to facilitate comparisons and highlight long-term trends. The 2013 report is not only stating the facts of the Significant System Events (ESS), but it moreover underlines the main elements dealing with the reliability of the electrical power system. It highlights the various elements which contribute to present and future reliability and provides an overview of the interaction between the various stakeholders of the Electrical Power System on the scale of the European Interconnected Network. (author)

  20. Challenges of designing fusion reactors for remote maintainability

    International Nuclear Information System (INIS)

    Masson, L.S.

    1981-01-01

    One of the major problems faced by the fusion community is the development of the high level of reliability required to assure that fusion will be a viable commercial power source. Much of the responsibility for solving this problem falls directly on the designer in developing concepts that have a high level of maintainability for the next generation engineering oriented reactors; and long range, in developing full maintainability for the more complicated commercial concepts with their required high level of on-line time. The near-term challenge will include development of unique design concepts to perform inspection, maintenance, replacement, and testing under the stringent conditions imposed by the next generation engineering oriented machines. The long range challenge will focus on basic design concepts that will enable the full maintainability required by commercial fusion. In addition to the purely technical challenges, the fusion community is also faced with the problem of developing programmatic means to assure that reactor maintenance issues are given proper and timely emphasis as the nuclear phase of fusion is approached

  1. The human factor in operation and maintenance of complex high-reliability systems

    International Nuclear Information System (INIS)

    Ryan, T.G.

    1989-01-01

    Human factors issues in probabilistic risk assessment (PRAs) of complex high-reliability systems are addressed. These PRAs influence system operation and technical support programs such as maintainability, test, and surveillance. Using the U.S. commercial nuclear power industry as the setting, the paper addresses the manner in which PRAs currently treat human performance, the state of quantification methods and source data for analyzing human performance, and the role of human factors specialist in the analysis. The paper concludes with a presentation of TALENT, an emerging concept for fully integrating broad-based human factors expertise into the PRA process, is presented. 47 refs

  2. What to Do With "Moderate" Reliability and Validity Coefficients?

    NARCIS (Netherlands)

    Post, Marcel W

    Clinimetric studies may use criteria for test-retest reliability and convergent validity such that correlation coefficients as low as .40 are supportive of reliability and validity. It can be argued that moderate (.40-.60) correlations should not be interpreted in this way and that reliability

  3. Nuclear reliability assurance data source guide

    International Nuclear Information System (INIS)

    1976-11-01

    Seven sources of reliability and maintainability data are reviewed for their potential for providing nuclear equipment data. Consideration is given to similarity to nuclear application, variety of equipment types reported, availability of data, and obsolescence of data. In addition, discussions of advantages and disadvantages of each data source are presented, and samples of either the data or the character of the data are included as appendixes

  4. Reliability of the Alzheimer's disease assessment scale (ADAS-Cog) in longitudinal studies.

    Science.gov (United States)

    Khan, Anzalee; Yavorsky, Christian; DiClemente, Guillermo; Opler, Mark; Liechti, Stacy; Rothman, Brian; Jovic, Sofija

    2013-11-01

    Considering the scarcity of longitudinal assessments of reliability, there is need for a more precise understanding of cognitive decline in Alzheimer's Disease (AD). The primary goal was to assess longitudinal changes in inter-rater reliability, test retest reliability and internal consistency of scores of the ADAS-Cog. 2,618 AD subjects were enrolled in seven randomized, double-blind, placebo-controlled, multicenter-trials from 1986 to 2009. Reliability, internal-consistency and cross-sectional analysis of ADAS-Cog and MMSE across seven visits were examined. Intra-class correlation (ICC) for ADAS-Cog was moderate to high supporting their reliability. Absolute Agreement ICCs 0.392 (Visit-7) to 0.806 (Visit-2) showed a progressive decrease in correlations across time. Item analysis revealed a decrease in item correlations, with the lowest correlations for Visit 7 for Commands (ICC=0.148), Comprehension (ICC=0.092), Spoken Language (ICC=0.044). Suitable assessment of AD treatments is maintained through accurate measurement of clinically significant outcomes. Targeted rater education ADAS-Cog items over-time can improve ability to administer and score the scale.

  5. Optimizing multiple reliable forward contracts for reservoir allocation using multitime scale streamflow forecasts

    Science.gov (United States)

    Lu, Mengqian; Lall, Upmanu; Robertson, Andrew W.; Cook, Edward

    2017-03-01

    Streamflow forecasts at multiple time scales provide a new opportunity for reservoir management to address competing objectives. Market instruments such as forward contracts with specified reliability are considered as a tool that may help address the perceived risk associated with the use of such forecasts in lieu of traditional operation and allocation strategies. A water allocation process that enables multiple contracts for water supply and hydropower production with different durations, while maintaining a prescribed level of flood risk reduction, is presented. The allocation process is supported by an optimization model that considers multitime scale ensemble forecasts of monthly streamflow and flood volume over the upcoming season and year, the desired reliability and pricing of proposed contracts for hydropower and water supply. It solves for the size of contracts at each reliability level that can be allocated for each future period, while meeting target end of period reservoir storage with a prescribed reliability. The contracts may be insurable, given that their reliability is verified through retrospective modeling. The process can allow reservoir operators to overcome their concerns as to the appropriate skill of probabilistic forecasts, while providing water users with short-term and long-term guarantees as to how much water or energy they may be allocated. An application of the optimization model to the Bhakra Dam, India, provides an illustration of the process. The issues of forecast skill and contract performance are examined. A field engagement of the idea is useful to develop a real-world perspective and needs a suitable institutional environment.

  6. Approach to reliability assessment

    International Nuclear Information System (INIS)

    Green, A.E.; Bourne, A.J.

    1975-01-01

    Experience has shown that reliability assessments can play an important role in the early design and subsequent operation of technological systems where reliability is at a premium. The approaches to and techniques for such assessments, which have been outlined in the paper, have been successfully applied in variety of applications ranging from individual equipments to large and complex systems. The general approach involves the logical and systematic establishment of the purpose, performance requirements and reliability criteria of systems. This is followed by an appraisal of likely system achievment based on the understanding of different types of variational behavior. A fundamental reliability model emerges from the correlation between the appropriate Q and H functions for performance requirement and achievement. This model may cover the complete spectrum of performance behavior in all the system dimensions

  7. 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....

  8. The rating reliability calculator

    Directory of Open Access Journals (Sweden)

    Solomon David J

    2004-04-01

    Full Text Available Abstract Background Rating scales form an important means of gathering evaluation data. Since important decisions are often based on these evaluations, determining the reliability of rating data can be critical. Most commonly used methods of estimating reliability require a complete set of ratings i.e. every subject being rated must be rated by each judge. Over fifty years ago Ebel described an algorithm for estimating the reliability of ratings based on incomplete data. While his article has been widely cited over the years, software based on the algorithm is not readily available. This paper describes an easy-to-use Web-based utility for estimating the reliability of ratings based on incomplete data using Ebel's algorithm. Methods The program is available public use on our server and the source code is freely available under GNU General Public License. The utility is written in PHP, a common open source imbedded scripting language. The rating data can be entered in a convenient format on the user's personal computer that the program will upload to the server for calculating the reliability and other statistics describing the ratings. Results When the program is run it displays the reliability, number of subject rated, harmonic mean number of judges rating each subject, the mean and standard deviation of the averaged ratings per subject. The program also displays the mean, standard deviation and number of ratings for each subject rated. Additionally the program will estimate the reliability of an average of a number of ratings for each subject via the Spearman-Brown prophecy formula. Conclusion This simple web-based program provides a convenient means of estimating the reliability of rating data without the need to conduct special studies in order to provide complete rating data. I would welcome other researchers revising and enhancing the program.

  9. Structural systems reliability analysis

    International Nuclear Information System (INIS)

    Frangopol, D.

    1975-01-01

    For an exact evaluation of the reliability of a structure it appears necessary to determine the distribution densities of the loads and resistances and to calculate the correlation coefficients between loads and between resistances. These statistical characteristics can be obtained only on the basis of a long activity period. In case that such studies are missing the statistical properties formulated here give upper and lower bounds of the reliability. (orig./HP) [de

  10. Reliability data book

    International Nuclear Information System (INIS)

    Bento, J.P.; Boerje, S.; Ericsson, G.; Hasler, A.; Lyden, C.O.; Wallin, L.; Poern, K.; Aakerlund, O.

    1985-01-01

    The main objective for the report is to improve failure data for reliability calculations as parts of safety analyses for Swedish nuclear power plants. The work is based primarily on evaluations of failure reports as well as information provided by the operation and maintenance staff of each plant. In the report are presented charts of reliability data for: pumps, valves, control rods/rod drives, electrical components, and instruments. (L.E.)

  11. Assessing the reliability of skilled performance

    International Nuclear Information System (INIS)

    Dougherty, E.M.; Collins, E.P.

    1996-01-01

    In some high-hazard military tasks, precision of motor skills is crucial to avoid a risk-sensitive drop or other mishap. Sparse data supports a basic level of reliability for this activity seemingly much lower than typical, individual action, slip-mode errors would yield. A typical occurrence failure rate seems to be of the order of 1 x 10 -5 per opportunity. A speculation is tendered that this represents a difference in kind; that the reliability of skills is a different taxon than previously called out in the typical scheme of human reliability

  12. A Survey of Network Reliability.

    Science.gov (United States)

    1983-07-01

    STATEMENT A. Atoyed for public releosel Oo . Distibution Unlimited JULY 1983 ORC 83-5 This research was supported by the Air Force Office of Scientific ...cONTso.oSoo oaoCC NaME ara AOoM It. REPORT DATE United States Air Force July 1983 Air Force Office of Scientific Research IL NUNeen or s Boiling Air Force Base...One node in K is designated the root and the reliability problem is to calculate the probability that the root can comunicate with the remaining K C V

  13. Multidisciplinary System Reliability Analysis

    Science.gov (United States)

    Mahadevan, Sankaran; Han, Song; Chamis, Christos C. (Technical Monitor)

    2001-01-01

    The objective of this study is to develop a new methodology for estimating the reliability of engineering systems that encompass multiple disciplines. The methodology is formulated in the context of the NESSUS probabilistic structural analysis code, developed under the leadership of NASA Glenn Research Center. The NESSUS code has been successfully applied to the reliability estimation of a variety of structural engineering systems. This study examines whether the features of NESSUS could be used to investigate the reliability of systems in other disciplines such as heat transfer, fluid mechanics, electrical circuits etc., without considerable programming effort specific to each discipline. In this study, the mechanical equivalence between system behavior models in different disciplines are investigated to achieve this objective. A new methodology is presented for the analysis of heat transfer, fluid flow, and electrical circuit problems using the structural analysis routines within NESSUS, by utilizing the equivalence between the computational quantities in different disciplines. This technique is integrated with the fast probability integration and system reliability techniques within the NESSUS code, to successfully compute the system reliability of multidisciplinary systems. Traditional as well as progressive failure analysis methods for system reliability estimation are demonstrated, through a numerical example of a heat exchanger system involving failure modes in structural, heat transfer and fluid flow disciplines.

  14. Using Vector Projection Method to evaluate maintainability of mechanical system in design review

    International Nuclear Information System (INIS)

    Chen Lu; Cai Jianguo

    2003-01-01

    Maintainability of a mechanical system is one of the system design parameters that has a great impact in terms of ease of maintenance. In this article, based on the definition of the terms of maintenance and maintainability, an important tool of Design for Maintenance is developed as a way to improve maintainability through design. A set of standard and organized guidelines is provided and maintainability factors in terms of physical design, logistics support and ergonomics are identified. As a specific application of design review, a methodology so called Vector Projection Method is developed to evaluate the maintainability of the mechanical system. Lastly, an example is discussed

  15. 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.

  16. 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

  17. Safety and reliability criteria

    International Nuclear Information System (INIS)

    O'Neil, R.

    1978-01-01

    Nuclear power plants and, in particular, reactor pressure boundary components have unique reliability requirements, in that usually no significant redundancy is possible, and a single failure can give rise to possible widespread core damage and fission product release. Reliability may be required for availability or safety reasons, but in the case of the pressure boundary and certain other systems safety may dominate. Possible Safety and Reliability (S and R) criteria are proposed which would produce acceptable reactor design. Without some S and R requirement the designer has no way of knowing how far he must go in analysing his system or component, or whether his proposed solution is likely to gain acceptance. The paper shows how reliability targets for given components and systems can be individually considered against the derived S and R criteria at the design and construction stage. Since in the case of nuclear pressure boundary components there is often very little direct experience on which to base reliability studies, relevant non-nuclear experience is examined. (author)

  18. 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.

  19. Issues in cognitive reliability

    International Nuclear Information System (INIS)

    Woods, D.D.; Hitchler, M.J.; Rumancik, J.A.

    1984-01-01

    This chapter examines some problems in current methods to assess reactor operator reliability at cognitive tasks and discusses new approaches to solve these problems. The two types of human failures are errors in the execution of an intention and errors in the formation/selection of an intention. Topics considered include the types of description, error correction, cognitive performance and response time, the speed-accuracy tradeoff function, function based task analysis, and cognitive task analysis. One problem of human reliability analysis (HRA) techniques in general is the question of what are the units of behavior whose reliability are to be determined. A second problem for HRA is that people often detect and correct their errors. The use of function based analysis, which maps the problem space for plant control, is recommended

  20. Human factors review of power plant maintainability. Final report

    International Nuclear Information System (INIS)

    Seminara, J.L.; Parsons, S.O.

    1981-02-01

    Human factors engineering is an interdisciplinary science and technology concerned with shaping the design of machines, facilities, and operational environments to promote safe, efficient, and reliable performance on the part of operators and maintainers of equipment systems. The human factors aspects of five nuclear power plants and four fossil fuel plants were evaluated using such methods as a check list guided observation system, structured interviews with maintenance personnel, direct observation of maintenance tasks, reviews of procedures, and analyses of maintenance errors or accidents by means of the critical incident technique. The study revealed a wide variety of human factors problem areas, most of which are extensively photodocumented. The study recommends that a more systematic and formal approach to ensure that future power plants are human engineered to the needs of maintenance personnel

  1. Optimal design of a maintainable cold-standby system

    Energy Technology Data Exchange (ETDEWEB)

    Yu Haiyang [Universite de technologie de Troyes, ISTIT, Rue Marie Curie, BP 2060, 10010 TROYES (France)]. E-mail: Haiyang.YU@utt.fr; Yalaoui, Farouk [Universite de technologie de Troyes, ISTIT, Rue Marie Curie, BP 2060, 10010 TROYES (France); Chatelet, Eric [Universite de technologie de Troyes, ISTIT, Rue Marie Curie, BP 2060, 10010 TROYES (France); Chu Chengbin [Universite de technologie de Troyes, ISTIT, Rue Marie Curie, BP 2060, 10010 TROYES (France); Management School, Hefei University of Technology, Hefei (China)

    2007-01-15

    This paper considers a framework to optimally design a maintainable cold-standby system. Not only the maintenance policy is to be determined, but also the reliability character of the components will be taken into account. Hence, the mean time to failure of the components and the policy time of good-as-new maintenances are proposed as decision variables. Following probability analyses, the system cost rate and the system availability are formulated as the optimization object and the constraint, respectively. Then, this optimization problem is directly resolved by recognizing its underlying properties. Moreover, the resolving procedure is found to be independent of the failure distributions of the components and the forms of the system cost, which is illustrated through a numerical example. As a conclusion, an exact method is successfully established to minimize the cost rate of a cold-standby system with the given maintenance facility.

  2. Optimal design of a maintainable cold-standby system

    International Nuclear Information System (INIS)

    Yu Haiyang; Yalaoui, Farouk; Chatelet, Eric; Chu Chengbin

    2007-01-01

    This paper considers a framework to optimally design a maintainable cold-standby system. Not only the maintenance policy is to be determined, but also the reliability character of the components will be taken into account. Hence, the mean time to failure of the components and the policy time of good-as-new maintenances are proposed as decision variables. Following probability analyses, the system cost rate and the system availability are formulated as the optimization object and the constraint, respectively. Then, this optimization problem is directly resolved by recognizing its underlying properties. Moreover, the resolving procedure is found to be independent of the failure distributions of the components and the forms of the system cost, which is illustrated through a numerical example. As a conclusion, an exact method is successfully established to minimize the cost rate of a cold-standby system with the given maintenance facility

  3. How Do Positive Views Maintain Life Satisfaction?

    Science.gov (United States)

    Wu, Chia-Huei; Tsai, Ying-Mei; Chen, Lung Hung

    2009-01-01

    This study proposes three mediation pathways to explain how the positive views (perceived control, optimism and self-enhancement) proposed by Cummins and Nistico (Journal of Happiness Studies 3:37-69 2002) maintain life satisfaction. The three pathways were enhancing self-esteem, reducing have-want discrepancy and changing importance perceptions.…

  4. Maintaining Contour Trees of Dynamic Terrains

    DEFF Research Database (Denmark)

    Agarwal, Pankaj K.; Mølhave, Thomas; Revsbæk, Morten

    2015-01-01

    We study the problem of maintaining the contour tree T of a terrain Sigma, represented as a triangulated xy-monotone surface, as the heights of its vertices vary continuously with time. We characterize the combinatorial changes in T and how they relate to topological changes in Sigma. We present ...

  5. Maintaining Contour Trees of Dynamic Terrains

    DEFF Research Database (Denmark)

    Agarwal, Pankaj K.; Arge, Lars; Mølhave, Thomas

    We consider maintaining the contour tree T of a piecewise-linear triangulation M that is the graph of a time varying height function h:R2→R. We carefully describe the combinatorial change in T that happen as h varies over time and how these changes relate to topological changes in M. We present a...

  6. Maintainability of manpower system with restricted recruitment ...

    African Journals Online (AJOL)

    The maintainability of a manpower system is studied under a Markov framework. The classical method of controlling only one factor of flow is extended to highlight the case in which two factors are under control simultaneously. One special case of this extension, where recruitment of units faces partial embargo, is given, ...

  7. Competence in radiation protection - acquisition, maintaining, extending

    International Nuclear Information System (INIS)

    Breckow, J.; Geringer, T.; Radiation Protection Academy Seibersdorf; Haug, T.

    2007-01-01

    A survey is given on current initiatives, supranational in the EU and national in Germany and Switzerland, for education and training in radiation protection with the aim of maintaining and enlarging professional competence. Successively, individual studying possibilities and courses as well as some experiences with guidelines for professional knowledge in Germany are described. (orig.)

  8. Reliability issues in PACS

    Science.gov (United States)

    Taira, Ricky K.; Chan, Kelby K.; Stewart, Brent K.; Weinberg, Wolfram S.

    1991-07-01

    Reliability is an increasing concern when moving PACS from the experimental laboratory to the clinical environment. Any system downtime may seriously affect patient care. The authors report on the several classes of errors encountered during the pre-clinical release of the PACS during the past several months and present the solutions implemented to handle them. The reliability issues discussed include: (1) environmental precautions, (2) database backups, (3) monitor routines of critical resources and processes, (4) hardware redundancy (networks, archives), and (5) development of a PACS quality control program.

  9. Reliability Parts Derating Guidelines

    Science.gov (United States)

    1982-06-01

    226-30, October 1974. 66 I, 26. "Reliability of GAAS Injection Lasers", De Loach , B. C., Jr., 1973 IEEE/OSA Conference on Laser Engineering and...Vol. R-23, No. 4, 226-30, October 1974. 28. "Reliability of GAAS Injection Lasers", De Loach , B. C., Jr., 1973 IEEE/OSA Conference on Laser...opnatien ot 󈨊 deg C, mounted on a 4-inach square 0.250~ inch thick al~loy alum~nusi panel.. This mounting technique should be L~ ken into cunoidur~tiou

  10. An assessment of maintainability of elevator system to improve facilities management knowledge-base

    Science.gov (United States)

    Siti, N. A.; Asmone, A. S.; Chew, M. Y. L.

    2018-02-01

    Elevator system is a highly specialized machinery that requires technicians that have a wider array of knowledge in maintaining the system to be safe and reliable. While attaining reliable data of elevator malfunction become challenges, this study has filled the gap by gathering the management-maintenance issues and operational defects of elevator system. Forty-three types of operation defects were found and the consequence defects and their possible causes of occurrences were discussed. To respond to the prime challenges of maintaining elevator system provided by the industry players’ perspective, a theoretical framework is established as a recommendation to improve knowledge base of defects in elevator system which comprises good practices, and solutions to rectify each defects found. Hence, this research paper has theoretically improved the knowledge base of maintainability of elevator system and provide meaningful guidelines in practical senses to the industry professionals.

  11. Reliability versus reproducibility

    International Nuclear Information System (INIS)

    Lautzenheiser, C.E.

    1976-01-01

    Defect detection and reproducibility of results are two separate but closely related subjects. It is axiomatic that a defect must be detected from examination to examination or reproducibility of results is very poor. On the other hand, a defect can be detected on each of subsequent examinations for higher reliability and still have poor reproducibility of results

  12. Power transformer reliability modelling

    NARCIS (Netherlands)

    Schijndel, van A.

    2010-01-01

    Problem description Electrical power grids serve to transport and distribute electrical power with high reliability and availability at acceptable costs and risks. These grids play a crucial though preferably invisible role in supplying sufficient power in a convenient form. Today’s society has

  13. Reliability and code level

    NARCIS (Netherlands)

    Kasperski, M.; Geurts, C.P.W.

    2005-01-01

    The paper describes the work of the IAWE Working Group WBG - Reliability and Code Level, one of the International Codification Working Groups set up at ICWE10 in Copenhagen. The following topics are covered: sources of uncertainties in the design wind load, appropriate design target values for the

  14. Reliability of Plastic Slabs

    DEFF Research Database (Denmark)

    Thoft-Christensen, Palle

    1989-01-01

    In the paper it is shown how upper and lower bounds for the reliability of plastic slabs can be determined. For the fundamental case it is shown that optimal bounds of a deterministic and a stochastic analysis are obtained on the basis of the same failure mechanisms and the same stress fields....

  15. Travel time reliability modeling.

    Science.gov (United States)

    2011-07-01

    This report includes three papers as follows: : 1. Guo F., Rakha H., and Park S. (2010), "A Multi-state Travel Time Reliability Model," : Transportation Research Record: Journal of the Transportation Research Board, n 2188, : pp. 46-54. : 2. Park S.,...

  16. Reliability and Model Fit

    Science.gov (United States)

    Stanley, Leanne M.; Edwards, Michael C.

    2016-01-01

    The purpose of this article is to highlight the distinction between the reliability of test scores and the fit of psychometric measurement models, reminding readers why it is important to consider both when evaluating whether test scores are valid for a proposed interpretation and/or use. It is often the case that an investigator judges both the…

  17. Parametric Mass Reliability Study

    Science.gov (United States)

    Holt, James P.

    2014-01-01

    The International Space Station (ISS) systems are designed based upon having redundant systems with replaceable orbital replacement units (ORUs). These ORUs are designed to be swapped out fairly quickly, but some are very large, and some are made up of many components. When an ORU fails, it is replaced on orbit with a spare; the failed unit is sometimes returned to Earth to be serviced and re-launched. Such a system is not feasible for a 500+ day long-duration mission beyond low Earth orbit. The components that make up these ORUs have mixed reliabilities. Components that make up the most mass-such as computer housings, pump casings, and the silicon board of PCBs-typically are the most reliable. Meanwhile components that tend to fail the earliest-such as seals or gaskets-typically have a small mass. To better understand the problem, my project is to create a parametric model that relates both the mass of ORUs to reliability, as well as the mass of ORU subcomponents to reliability.

  18. The importance of the reliability study for the safety operation of chemical plants. Application in heavy water plants

    International Nuclear Information System (INIS)

    Dumitrescu, Maria; Lazar, Roxana Elena; Preda, Irina Aida; Stefanescu, Ioan

    1999-01-01

    Heavy water production in Romania is based on H 2 O-H 2 S isotopic exchange process followed by vacuum isotopic distillation. The heavy water plant are complex chemical systems, characterized by an ensemble of static and dynamic equipment, AMC components, enclosures. Such equipment must have a high degree of reliability, a maximum safety in technological operation and a high availability index. Safety, reliable and economical operation heavy water plants need to maintain the systems and the components at adequate levels of reliability. The paper is a synthesis of the qualitative and quantitative assessment reliability studies for heavy water plants. The operation analysis on subsystems, each subsystems being a well-defined unit, is required by the plant complexity. For each component the reliability indicators were estimated by parametric and non-parametric methods based on the plant operation data. Also, the reliability qualitative and quantitative assessment was done using the fault tree technique. For the dual temperature isotopic exchange plants the results indicate an increase of the MTBF after the first years of operation, illustrating both the operation experience increasing and maintenance improvement. Also a high degree of availability was illustrated by the reliability studies of the vacuum distillation plant. The establishment of the reliability characteristics for heavy water plant represents an important step, a guide for highlighting the elements and process liable to failure being at the same time a planning modality to correlate the control times with the maintenance operations. This is the way to minimise maintenance, control and costs. The main purpose of the reliability study was the safety increase of the plant operation and the support for decision making. (authors)

  19. Mechanical properties of different types of space maintainers

    Science.gov (United States)

    Beldiman, M.-A.; Mârţu, I.; Leiţoiu, B.; Luchian, I.; Lupescu, O.; Bârcă, E. S.

    2015-11-01

    Currently, inside the oral cavity, the dental space maintainers are subjected to forces exerted on them when performing various functions; therefore, it is important to know how each of these mechanisms behave and respond to forces that are applied directly to them. The mechanical properties of the materials used in dentistry are defined by a set of characteristics representing the behaviour of their particular working conditions and it is qualitatively expressed by a number of parameters.The study aimed to determine the pressing force that can be taken by four 4 types of space maintainers frequently used in practice - fixed and removable, applied on four samples realized with human teeth extracted for orthodontic purposes. Static tests were carried out on a machine type short WDW-5 EC with a maximum force of 5 kN and a loading speed of 5 mm/min by a special testing machine, with an innovative appliance; data recording was automatically performed, using a computer with a special program that present the specific diagrams. Experimental determinations included the following aspects: to determine the maximum force that can be supported by each sample, and to observe the deformations. The values obtained indicate that the best option in terms of behavior under the conditions specified is the removable appliance, and the less functional version is the fixed space maintainer using brackets. According to tests conducted, the fracture strength was found to be more important for fixed space maintainers (band and loop, for example) so, in practice is using more frequent these types of space maintainers.

  20. Dicer maintains the identity and function of proprioceptive sensory neurons.

    Science.gov (United States)

    O'Toole, Sean M; Ferrer, Monica M; Mekonnen, Jennifer; Zhang, Haihan; Shima, Yasuyuki; Ladle, David R; Nelson, Sacha B

    2017-03-01

    Neuronal cell identity is established during development and must be maintained throughout an animal's life (Fishell G, Heintz N. Neuron 80: 602-612, 2013). Transcription factors critical for establishing neuronal identity can be required for maintaining it (Deneris ES, Hobert O. Nat Neurosci 17: 899-907, 2014). Posttranscriptional regulation also plays an important role in neuronal differentiation (Bian S, Sun T. Mol Neurobiol 44: 359-373, 2011), but its role in maintaining cell identity is less established. To better understand how posttranscriptional regulation might contribute to cell identity, we examined the proprioceptive neurons in the dorsal root ganglion (DRG), a highly specialized sensory neuron class, with well-established properties that distinguish them from other neurons in the ganglion. By conditionally ablating Dicer in mice, using parvalbumin (Pvalb)-driven Cre recombinase, we impaired posttranscriptional regulation in the proprioceptive sensory neuron population. Knockout (KO) animals display a progressive form of ataxia at the beginning of the fourth postnatal week that is accompanied by a cell death within the DRG. Before cell loss, expression profiling shows a reduction of proprioceptor specific genes and an increased expression of nonproprioceptive genes normally enriched in other ganglion neurons. Furthermore, although central connections of these neurons are intact, the peripheral connections to the muscle are functionally impaired. Posttranscriptional regulation is therefore necessary to retain the transcriptional identity and support functional specialization of the proprioceptive sensory neurons. NEW & NOTEWORTHY We have demonstrated that selectively impairing Dicer in parvalbumin-positive neurons, which include the proprioceptors, triggers behavioral changes, a lack of muscle connectivity, and a loss of transcriptional identity as observed through RNA sequencing. These results suggest that Dicer and, most likely by extension, micro

  1. STARS software tool for analysis of reliability and safety

    International Nuclear Information System (INIS)

    Poucet, A.; Guagnini, E.

    1989-01-01

    This paper reports on the STARS (Software Tool for the Analysis of Reliability and Safety) project aims at developing an integrated set of Computer Aided Reliability Analysis tools for the various tasks involved in systems safety and reliability analysis including hazard identification, qualitative analysis, logic model construction and evaluation. The expert system technology offers the most promising perspective for developing a Computer Aided Reliability Analysis tool. Combined with graphics and analysis capabilities, it can provide a natural engineering oriented environment for computer assisted reliability and safety modelling and analysis. For hazard identification and fault tree construction, a frame/rule based expert system is used, in which the deductive (goal driven) reasoning and the heuristic, applied during manual fault tree construction, is modelled. Expert system can explain their reasoning so that the analyst can become aware of the why and the how results are being obtained. Hence, the learning aspect involved in manual reliability and safety analysis can be maintained and improved

  2. Reliability Approach of a Compressor System using Reliability Block ...

    African Journals Online (AJOL)

    pc

    2018-03-05

    Mar 5, 2018 ... This paper presents a reliability analysis of such a system using reliability ... Keywords-compressor system, reliability, reliability block diagram, RBD .... the same structure has been kept with the three subsystems: air flow, oil flow and .... and Safety in Engineering Design", Springer, 2009. [3] P. O'Connor ...

  3. Secure Reliable Processing Systems

    Science.gov (United States)

    1984-02-21

    be attainable in principle, the more difficult goal is to meet all of the above while still maintaining good performance within the framwork of a well...managing the network, the user sees a conceptually simpler storage facility, composed merely of files, without machine boundaries, replicated copies

  4. The effect of resource history on the functioning of soil microbial communities is maintained across time

    Science.gov (United States)

    Keiser, A. D.; Strickland, M. S.; Fierer, N.; Bradford, M. A.

    2011-06-01

    Historical resource conditions appear to influence microbial community function. With time, historical influences might diminish as populations respond to the contemporary environment. Alternatively, they may persist given factors such as contrasting genetic potentials for adaptation to a new environment. Using experimental microcosms, we test competing hypotheses that function of distinct soil microbial communities in common environments (H1a) converge or (H1b) remain dissimilar over time. Using a 6 × 2 (soil community inoculum × litter environment) full-factorial design, we compare decomposition rates in experimental microcosms containing grass or hardwood litter environments. After 100 days, communities that develop are inoculated into fresh litters and decomposition followed for another 100 days. We repeat this for a third, 100-day period. In each successive, 100-day period, we find higher decomposition rates (i.e. functioning) suggesting communities function better when they have an experimental history of the contemporary environment. Despite these functional gains, differences in decomposition rates among initially distinct communities persist, supporting the hypothesis that dissimilarity is maintained across time. In contrast to function, community composition is more similar following a common, experimental history. We also find that "specialization" on one experimental environment incurs a cost, with loss of function in the alternate environment. For example, experimental history of a grass-litter environment reduced decomposition when communities were inoculated into a hardwood-litter environment. Our work demonstrates experimentally that despite expectations of fast growth rates, physiological flexibility and rapid evolution, initial functional differences between microbial communities are maintained across time. These findings question whether microbial dynamics can be omitted from models of ecosystem processes if we are to predict reliably global

  5. Breeding and maintaining high-quality insects

    DEFF Research Database (Denmark)

    Jensen, Kim; Kristensen, Torsten Nygård; Heckmann, Lars-Henrik

    2017-01-01

    Insects have a large potential for sustainably enhancing global food and feed production, and commercial insect production is a rising industry of high economic value. Insects suitable for production typically have fast growth, short generation time, efficient nutrient utilization, high...... reproductive potential, and thrive at high density. Insects may cost-efficiently convert agricultural and industrial food by-products into valuable protein once the technology is finetuned. However, since insect mass production is a new industry, the technology needed to efficiently farm these animals is still...... in a starting phase. Here, we discuss the challenges and precautions that need to be considered when breeding and maintaining high-quality insect populations for food and feed. This involves techniques typically used in domestic animal breeding programs including maintaining genetically healthy populations...

  6. Maintaining Respiratory Health in Cystic Fibrosis Patients

    Directory of Open Access Journals (Sweden)

    MR Modaresi

    2014-04-01

    Full Text Available Cystic fibrosis (CF is an inherited disease that primarily affects the lungs and the digestive system, however, it also affects a number of other organs and systems. More than 90% of mortality of  CF patients is due to lung complications.  Healthy lungs are important for a long life for people with CF, We will discuss two important topics for maintaining respiratory health. Chronic use of drugs for maintaining respiratory health There are a number of drugs available to keep CF lungs healthy. We will discuss the science behind the recommendations for use of: Inhaled antibiotics Dornase alfa Azithromycin Hypertonic saline High-dose ibuprofen Ivacaftor CF Airway Clearance Therapies Airway Clearance therapy is very important to keeping CF lungs healthy. Our discussions cover the following topics such as the: Daily airway clearance Different techniques of airway clearance Effect of aerobic exercise on airway clearance  

  7. Maintaining the Identify of Dynamically Embodied Agents

    OpenAIRE

    Martin, Alan; O'Hare, Gregory; Duffy, Brian; Schoen-Phelan, Bianca; Bradley, John

    2005-01-01

    Virtual agents are traditionally constrained in their embod- iment, as they are restricted to one form of body. We propose allowing them to change their embodiment in order to expand their capabili- ties. This presents users with a number of di±culties in maintaining the identity of the agents, but these can be overcome by using identity cues, certain features that remain constant across embodiment forms. This pa- per outlines an experiment that examines these identity cues, and shows that th...

  8. Reliability in the utility computing era: Towards reliable Fog computing

    DEFF Research Database (Denmark)

    Madsen, Henrik; Burtschy, Bernard; Albeanu, G.

    2013-01-01

    This paper considers current paradigms in computing and outlines the most important aspects concerning their reliability. The Fog computing paradigm as a non-trivial extension of the Cloud is considered and the reliability of the networks of smart devices are discussed. Combining the reliability...... requirements of grid and cloud paradigms with the reliability requirements of networks of sensor and actuators it follows that designing a reliable Fog computing platform is feasible....

  9. Water quality maintaining device of power plant

    International Nuclear Information System (INIS)

    Kobayashi, Minoru; Inami, Ichiro.

    1994-01-01

    The device of the present invention reduces the amount of leaching materials of ion exchange resins from a water processing system of a BWR tyep plant, improves the water quality of reactor water to maintain the water at high purity. That is, steams used for power generation are condensated in a condensate system. A condensate filter and a condensate desalter for cleaning the condensates are disposed. A resin storage hopper is disposed for supplying the ion exchange resins to the water processing system. A device for supplying a nitrogen gas or an inert gas is disposed in the hopper. With such a constitution, the ion exchange resins in the water processing system are maintained in a nitrogen gas or inert gas atmosphere or at a low dissolved oxygen level in an operation stage in the power plant. Accordingly, degradation of the ion exchange resins in the water processing system is suppressed and the amount of the leaching material from the resins is reduced. As a result, the amount of the resins leached into the reactor is reduced, so that the reactor water quality can be maintained at high purity. (I.S.)

  10. Engineering systems reliability, safety, and maintenance an integrated approach

    CERN Document Server

    Dhillon, B S

    2017-01-01

    Today, engineering systems are an important element of the world economy and each year billions of dollars are spent to develop, manufacture, operate, and maintain various types of engineering systems around the globe. Many of these systems are highly sophisticated and contain millions of parts. For example, a Boeing jumbo 747 is made up of approximately 4.5 million parts including fasteners. Needless to say, reliability, safety, and maintenance of systems such as this have become more important than ever before.  Global competition and other factors are forcing manufacturers to produce highly reliable, safe, and maintainable engineering products. Therefore, there is a definite need for the reliability, safety, and maintenance professionals to work closely during design and other phases. Engineering Systems Reliability, Safety, and Maintenance: An Integrated Approach eliminates the need to consult many different and diverse sources in the hunt for the information required to design better engineering syste...

  11. Resolution of GSI B-56 - Emergency diesel generator reliability

    International Nuclear Information System (INIS)

    Serkiz, A.W.

    1989-01-01

    The need for an emergency diesel generator (EDG) reliability program has been established by 10 CFR Part 50, Section 50.63, Loss of All Alternating Current Power, which requires that licensees assess their station blackout coping and recovery capability. EDGs are the principal emergency ac power sources for avoiding a station blackout. Regulatory Guide 1.155, Station Blackout, identifies a need for (1) a nuclear unit EDG reliability level of at least 0.95, and (2) an EDG reliability program to monitor and maintain the required EDG reliability levels. NUMARC-8700, Guidelines and Technical Bases for NUMARC Initiatives Addressing Station Blackout at Light Water Reactors, also provides guidance on such needs. The resolution of GSI B-56, Diesel Reliability will be accomplished by issuing Regulatory Guide 1.9, Rev. 3, Selection, Design, Qualification, Testing, and Reliability of Diesel Generator Units Used as Onsite Electric Power Systems at Nuclear Plants. This revision will integrate into a single regulatory guide pertinent guidance previously addressed in R.G. 1.9, Rev. 2, R.G. 1.108, and Generic Letter 84-15. R.G. 1.9 has been expanded to define the principal elements of an EDG reliability program for monitoring and maintaining EDG reliability levels selected for SBO. In addition, alert levels and corrective actions have been defined to detect a deteriorating situation for all EDGs assigned to a particular nuclear unit, as well as an individual problem EDG

  12. Validity and Reliability in Social Science Research

    Science.gov (United States)

    Drost, Ellen A.

    2011-01-01

    In this paper, the author aims to provide novice researchers with an understanding of the general problem of validity in social science research and to acquaint them with approaches to developing strong support for the validity of their research. She provides insight into these two important concepts, namely (1) validity; and (2) reliability, and…

  13. JWIG: Yet Another Framework for Maintainable and Secure Web Applications

    DEFF Research Database (Denmark)

    Møller, Anders; Schwarz, Mathias Romme

    2009-01-01

    Although numerous frameworks for web application programming have been developed in recent years, writing web applications remains a challenging task. Guided by a collection of classical design principles, we propose yet another framework. It is based on a simple but flexible server......-oriented architecture that coherently supports general aspects of modern web applications, including dynamic XML construction, session management, data persistence, caching, and authentication, but it also simplifies programming of server-push communication and integration of XHTML-based applications and XML-based web...... services.The resulting framework provides a novel foundation for developing maintainable and secure web applications....

  14. A reliability analysis of the revised competitiveness index.

    Science.gov (United States)

    Harris, Paul B; Houston, John M

    2010-06-01

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

  15. Waste package reliability analysis

    International Nuclear Information System (INIS)

    Pescatore, C.; Sastre, C.

    1983-01-01

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

  16. Accelerator reliability workshop

    Energy Technology Data Exchange (ETDEWEB)

    Hardy, L; Duru, Ph; Koch, J M; Revol, J L; Van Vaerenbergh, P; Volpe, A M; Clugnet, K; Dely, A; Goodhew, D

    2002-07-01

    About 80 experts attended this workshop, which brought together all accelerator communities: accelerator driven systems, X-ray sources, medical and industrial accelerators, spallation sources projects (American and European), nuclear physics, etc. With newly proposed accelerator applications such as nuclear waste transmutation, replacement of nuclear power plants and others. Reliability has now become a number one priority for accelerator designers. Every part of an accelerator facility from cryogenic systems to data storage via RF systems are concerned by reliability. This aspect is now taken into account in the design/budget phase, especially for projects whose goal is to reach no more than 10 interruptions per year. This document gathers the slides but not the proceedings of the workshop.

  17. Human Reliability Program Workshop

    Energy Technology Data Exchange (ETDEWEB)

    Landers, John; Rogers, Erin; Gerke, Gretchen

    2014-05-18

    A Human Reliability Program (HRP) is designed to protect national security as well as worker and public safety by continuously evaluating the reliability of those who have access to sensitive materials, facilities, and programs. Some elements of a site HRP include systematic (1) supervisory reviews, (2) medical and psychological assessments, (3) management evaluations, (4) personnel security reviews, and (4) training of HRP staff and critical positions. Over the years of implementing an HRP, the Department of Energy (DOE) has faced various challenges and overcome obstacles. During this 4-day activity, participants will examine programs that mitigate threats to nuclear security and the insider threat to include HRP, Nuclear Security Culture (NSC) Enhancement, and Employee Assistance Programs. The focus will be to develop an understanding of the need for a systematic HRP and to discuss challenges and best practices associated with mitigating the insider threat.

  18. Reliability and construction control

    Directory of Open Access Journals (Sweden)

    Sherif S. AbdelSalam

    2016-06-01

    Full Text Available The goal of this study was to determine the most reliable and efficient combination of design and construction methods required for vibro piles. For a wide range of static and dynamic formulas, the reliability-based resistance factors were calculated using EGYPT database, which houses load test results for 318 piles. The analysis was extended to introduce a construction control factor that determines the variation between the pile nominal capacities calculated using static versus dynamic formulae. From the major outcomes, the lowest coefficient of variation is associated with Davisson’s criterion, and the resistance factors calculated for the AASHTO method are relatively high compared with other methods. Additionally, the CPT-Nottingham and Schmertmann method provided the most economic design. Recommendations related to a pile construction control factor were also presented, and it was found that utilizing the factor can significantly reduce variations between calculated and actual capacities.

  19. Scyllac equipment reliability analysis

    International Nuclear Information System (INIS)

    Gutscher, W.D.; Johnson, K.J.

    1975-01-01

    Most of the failures in Scyllac can be related to crowbar trigger cable faults. A new cable has been designed, procured, and is currently undergoing evaluation. When the new cable has been proven, it will be worked into the system as quickly as possible without causing too much additional down time. The cable-tip problem may not be easy or even desirable to solve. A tightly fastened permanent connection that maximizes contact area would be more reliable than the plug-in type of connection in use now, but it would make system changes and repairs much more difficult. The balance of the failures have such a low occurrence rate that they do not cause much down time and no major effort is underway to eliminate them. Even though Scyllac was built as an experimental system and has many thousands of components, its reliability is very good. Because of this the experiment has been able to progress at a reasonable pace

  20. Improving Power Converter Reliability

    DEFF Research Database (Denmark)

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

    2014-01-01

    of a high-power IGBT module during converter operation, which may play a vital role in improving the reliability of the power converters. The measured voltage is used to estimate the module average junction temperature of the high and low-voltage side of a half-bridge IGBT separately in every fundamental......The real-time junction temperature monitoring of a high-power insulated-gate bipolar transistor (IGBT) module is important to increase the overall reliability of power converters for industrial applications. This article proposes a new method to measure the on-state collector?emitter voltage...... is measured in a wind power converter at a low fundamental frequency. To illustrate more, the test method as well as the performance of the measurement circuit are also presented. This measurement is also useful to indicate failure mechanisms such as bond wire lift-off and solder layer degradation...

  1. Accelerator reliability workshop

    International Nuclear Information System (INIS)

    Hardy, L.; Duru, Ph.; Koch, J.M.; Revol, J.L.; Van Vaerenbergh, P.; Volpe, A.M.; Clugnet, K.; Dely, A.; Goodhew, D.

    2002-01-01

    About 80 experts attended this workshop, which brought together all accelerator communities: accelerator driven systems, X-ray sources, medical and industrial accelerators, spallation sources projects (American and European), nuclear physics, etc. With newly proposed accelerator applications such as nuclear waste transmutation, replacement of nuclear power plants and others. Reliability has now become a number one priority for accelerator designers. Every part of an accelerator facility from cryogenic systems to data storage via RF systems are concerned by reliability. This aspect is now taken into account in the design/budget phase, especially for projects whose goal is to reach no more than 10 interruptions per year. This document gathers the slides but not the proceedings of the workshop

  2. Safety and reliability assessment

    International Nuclear Information System (INIS)

    1979-01-01

    This report contains the papers delivered at the course on safety and reliability assessment held at the CSIR Conference Centre, Scientia, Pretoria. The following topics were discussed: safety standards; licensing; biological effects of radiation; what is a PWR; safety principles in the design of a nuclear reactor; radio-release analysis; quality assurance; the staffing, organisation and training for a nuclear power plant project; event trees, fault trees and probability; Automatic Protective Systems; sources of failure-rate data; interpretation of failure data; synthesis and reliability; quantification of human error in man-machine systems; dispersion of noxious substances through the atmosphere; criticality aspects of enrichment and recovery plants; and risk and hazard analysis. Extensive examples are given as well as case studies

  3. The cost of reliability

    International Nuclear Information System (INIS)

    Ilic, M.

    1998-01-01

    In this article the restructuring process under way in the US power industry is being revisited from the point of view of transmission system provision and reliability was rolled into the average cost of electricity to all, it is not so obvious how is this cost managed in the new industry. A new MIT approach to transmission pricing is here suggested as a possible solution [it

  4. Life Support for Deep Space and Mars

    Science.gov (United States)

    Jones, Harry W.; Hodgson, Edward W.; Kliss, Mark H.

    2014-01-01

    How should life support for deep space be developed? The International Space Station (ISS) life support system is the operational result of many decades of research and development. Long duration deep space missions such as Mars have been expected to use matured and upgraded versions of ISS life support. Deep space life support must use the knowledge base incorporated in ISS but it must also meet much more difficult requirements. The primary new requirement is that life support in deep space must be considerably more reliable than on ISS or anywhere in the Earth-Moon system, where emergency resupply and a quick return are possible. Due to the great distance from Earth and the long duration of deep space missions, if life support systems fail, the traditional approaches for emergency supply of oxygen and water, emergency supply of parts, and crew return to Earth or escape to a safe haven are likely infeasible. The Orbital Replacement Unit (ORU) maintenance approach used by ISS is unsuitable for deep space with ORU's as large and complex as those originally provided in ISS designs because it minimizes opportunities for commonality of spares, requires replacement of many functional parts with each failure, and results in substantial launch mass and volume penalties. It has become impractical even for ISS after the shuttle era, resulting in the need for ad hoc repair activity at lower assembly levels with consequent crew time penalties and extended repair timelines. Less complex, more robust technical approaches may be needed to meet the difficult deep space requirements for reliability, maintainability, and reparability. Developing an entirely new life support system would neglect what has been achieved. The suggested approach is use the ISS life support technologies as a platform to build on and to continue to improve ISS subsystems while also developing new subsystems where needed to meet deep space requirements.

  5. Software reliability studies

    Science.gov (United States)

    Hoppa, Mary Ann; Wilson, Larry W.

    1994-01-01

    There are many software reliability models which try to predict future performance of software based on data generated by the debugging process. Our research has shown that by improving the quality of the data one can greatly improve the predictions. We are working on methodologies which control some of the randomness inherent in the standard data generation processes in order to improve the accuracy of predictions. Our contribution is twofold in that we describe an experimental methodology using a data structure called the debugging graph and apply this methodology to assess the robustness of existing models. The debugging graph is used to analyze the effects of various fault recovery orders on the predictive accuracy of several well-known software reliability algorithms. We found that, along a particular debugging path in the graph, the predictive performance of different models can vary greatly. Similarly, just because a model 'fits' a given path's data well does not guarantee that the model would perform well on a different path. Further we observed bug interactions and noted their potential effects on the predictive process. We saw that not only do different faults fail at different rates, but that those rates can be affected by the particular debugging stage at which the rates are evaluated. Based on our experiment, we conjecture that the accuracy of a reliability prediction is affected by the fault recovery order as well as by fault interaction.

  6. Investment in new product reliability

    International Nuclear Information System (INIS)

    Murthy, D.N.P.; Rausand, M.; Virtanen, S.

    2009-01-01

    Product reliability is of great importance to both manufacturers and customers. Building reliability into a new product is costly, but the consequences of inadequate product reliability can be costlier. This implies that manufacturers need to decide on the optimal investment in new product reliability by achieving a suitable trade-off between the two costs. This paper develops a framework and proposes an approach to help manufacturers decide on the investment in new product reliability.

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

    International Nuclear Information System (INIS)

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

    1998-03-01

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

  8. Establishing and maintaining international collaborative research teams: an autobiographical insight

    Directory of Open Access Journals (Sweden)

    T J Carr

    2013-07-01

    Full Text Available Despite the growing impetus for international collaborative research teams (ICRT, there are relatively few resources available to guide and support researchers through the processes of establishing and maintaining ICRTs. In particular, no articles were found that provided researchers’ firsthand accounts of being a member of such a team. Having access to such personal accounts can help both experienced and novice researchers learn more directly about what to expect, as well as the benefits, challenges, pitfalls, and success strategies for establishing and maintaining ICRTs. The authors used phenomenological autobiographical reflective journaling to capture their experiences as members of ICRTs. In this article we provide an overview of key themes that emerged from the analysis of our reflections as members of ICRTs. These themes include: benefits, challenges, and strategies for success. Our aim is to share our first-hand experiences of what it is like to establish and participate in ICRT. It is not our intention to provide readers with prescriptive guidelines on how to set up and maintain ICRTs. Every ICRT is unique and some of these ideas may or may not apply in every case. Instead, we are describing what worked for us, hoping that others may benefit from our experience. Consequently, we suggest that the focus of ICRT should be on the benefits thereof which promote and encourage interaction between disciplines, transfer of knowledge and techniques and personal and professional development. Keywords: international, collaborative, research, teams, interdisciplinary

  9. Human Reliability Analysis: session summary

    International Nuclear Information System (INIS)

    Hall, R.E.

    1985-01-01

    The use of Human Reliability Analysis (HRA) to identify and resolve human factors issues has significantly increased over the past two years. Today, utilities, research institutions, consulting firms, and the regulatory agency have found a common application of HRA tools and Probabilistic Risk Assessment (PRA). The ''1985 IEEE Third Conference on Human Factors and Power Plants'' devoted three sessions to the discussion of these applications and a review of the insights so gained. This paper summarizes the three sessions and presents those common conclusions that were discussed during the meeting. The paper concludes that session participants supported the use of an adequately documented ''living PRA'' to address human factors issues in design and procedural changes, regulatory compliance, and training and that the techniques can produce cost effective qualitative results that are complementary to more classical human factors methods

  10. Interim reliability evaluation program (IREP)

    International Nuclear Information System (INIS)

    Carlson, D.D.; Murphy, J.A.

    1981-01-01

    The Interim Reliability Evaluation Program (IREP), sponsored by the Office of Nuclear Regulatory Research of the US Nuclear Regulatory Commission, is currently applying probabilistic risk analysis techniques to two PWR and two BWR type power plants. Emphasis was placed on the systems analysis portion of the risk assessment, as opposed to accident phenomenology or consequence analysis, since the identification of risk significant plant features was of primary interest. Traditional event tree/fault tree modeling was used for the analysis. However, the study involved a more thorough investigation of transient initiators and of support system faults than studies in the past and substantially improved techniques were used to quantify accident sequence frequencies. This study also attempted to quantify the potential for operator recovery actions in the course of each significant accident

  11. Identifying crucial parameter correlations maintaining bursting activity.

    Directory of Open Access Journals (Sweden)

    Anca Doloc-Mihu

    2014-06-01

    Full Text Available Recent experimental and computational studies suggest that linearly correlated sets of parameters (intrinsic and synaptic properties of neurons allow central pattern-generating networks to produce and maintain their rhythmic activity regardless of changing internal and external conditions. To determine the role of correlated conductances in the robust maintenance of functional bursting activity, we used our existing database of half-center oscillator (HCO model instances of the leech heartbeat CPG. From the database, we identified functional activity groups of burster (isolated neuron and half-center oscillator model instances and realistic subgroups of each that showed burst characteristics (principally period and spike frequency similar to the animal. To find linear correlations among the conductance parameters maintaining functional leech bursting activity, we applied Principal Component Analysis (PCA to each of these four groups. PCA identified a set of three maximal conductances (leak current, [Formula: see text]Leak; a persistent K current, [Formula: see text]K2; and of a persistent Na+ current, [Formula: see text]P that correlate linearly for the two groups of burster instances but not for the HCO groups. Visualizations of HCO instances in a reduced space suggested that there might be non-linear relationships between these parameters for these instances. Experimental studies have shown that period is a key attribute influenced by modulatory inputs and temperature variations in heart interneurons. Thus, we explored the sensitivity of period to changes in maximal conductances of [Formula: see text]Leak, [Formula: see text]K2, and [Formula: see text]P, and we found that for our realistic bursters the effect of these parameters on period could not be assessed because when varied individually bursting activity was not maintained.

  12. Store operations to maintain cache coherence

    Energy Technology Data Exchange (ETDEWEB)

    Evangelinos, Constantinos; Nair, Ravi; Ohmacht, Martin

    2017-08-01

    In one embodiment, a computer-implemented method includes encountering a store operation during a compile-time of a program, where the store operation is applicable to a memory line. It is determined, by a computer processor, that no cache coherence action is necessary for the store operation. A store-without-coherence-action instruction is generated for the store operation, responsive to determining that no cache coherence action is necessary. The store-without-coherence-action instruction specifies that the store operation is to be performed without a cache coherence action, and cache coherence is maintained upon execution of the store-without-coherence-action instruction.

  13. Store operations to maintain cache coherence

    Energy Technology Data Exchange (ETDEWEB)

    Evangelinos, Constantinos; Nair, Ravi; Ohmacht, Martin

    2017-09-12

    In one embodiment, a computer-implemented method includes encountering a store operation during a compile-time of a program, where the store operation is applicable to a memory line. It is determined, by a computer processor, that no cache coherence action is necessary for the store operation. A store-without-coherence-action instruction is generated for the store operation, responsive to determining that no cache coherence action is necessary. The store-without-coherence-action instruction specifies that the store operation is to be performed without a cache coherence action, and cache coherence is maintained upon execution of the store-without-coherence-action instruction.

  14. Acceptability and reliability of an adolescent risk behavior questionnaire administered with audio and computer support Aceptabilidad y fiabilidad de un cuestionario sobre el comportamiento de riesgo de los adolescentes aplicado con el apoyo de audio y computadora

    Directory of Open Access Journals (Sweden)

    Juan Pablo Gutiérrez

    2009-05-01

    Full Text Available OBJECTIVE: To test acceptability and reliability of audio computer-assisted self-interviewing (ACASI system administered at the household level to gather data on risk behaviors among adolescents in Mexico. METHODS: Answers to sensitive behavior-related questions obtained using ACASI systems were compared with answers to the same questions obtained through face-to-face interviews (FFIs. Focus groups were conducted to explore ACASI acceptability among adolescents and its feasibility in obtaining better self-reported data on sensitive behaviors. RESULTS: ACASI was adolescents' preferred method for reporting risk behaviors, particularly sexual behavior, and did not pose greater challenges to respondents versus FFIs. Also, more risk behaviors were reported through ACASI versus FFIs. CONCLUSION: The use of ACASI systems in disadvantaged households to obtain data on adolescent risk behavior is not only feasible but may also improve data quality in the case of complex questionnaires, compared with FFIs, and should therefore be considered as an alternative survey method.OBJETIVO: Evaluar la aceptabilidad y fiabilidad de un sistema de autoentrevista asistido por audio y computadora (ACASI aplicado en los hogares para recopilar información sobre el comportamiento de riesgo de los adolescentes en México. MÉTODOS: Se compararon las respuestas obtenidas mediante el sistema ACASI y entrevistas cara a cara (FFI sobre aspectos sensibles del comportamiento. Se analizó en grupos focales la aceptabilidad de ACASI para los adolescentes y la factibilidad de obtener mejor información en los autoinformes sobre aspectos sensibles de su conducta. RESULTADOS: Los adolescentes prefirieron el sistema ACASI para informar sobre conductas de riesgo, en particular las relacionadas con el sexo, y no constituyó un mayor reto para los entrevistados en comparación con las FFI. Se informaron más comportamientos de riesgo mediante ACASI que en las FFI. CONCLUSIONES: El empleo

  15. NDE reliability and advanced NDE technology validation

    International Nuclear Information System (INIS)

    Doctor, S.R.; Deffenbaugh, J.D.; Good, M.S.; Green, E.R.; Heasler, P.G.; Hutton, P.H.; Reid, L.D.; Simonen, F.A.; Spanner, J.C.; Vo, T.V.

    1989-01-01

    This paper reports on progress for three programs: (1) evaluation and improvement in nondestructive examination reliability for inservice inspection of light water reactors (LWR) (NDE Reliability Program), (2) field validation acceptance, and training for advanced NDE technology, and (3) evaluation of computer-based NDE techniques and regional support of inspection activities. The NDE Reliability Program objectives are to quantify the reliability of inservice inspection techniques for LWR primary system components through independent research and establish means for obtaining improvements in the reliability of inservice inspections. The areas of significant progress will be described concerning ASME Code activities, re-analysis of the PISC-II data, the equipment interaction matrix study, new inspection criteria, and PISC-III. The objectives of the second program are to develop field procedures for the AE and SAFT-UT techniques, perform field validation testing of these techniques, provide training in the techniques for NRC headquarters and regional staff, and work with the ASME Code for the use of these advanced technologies. The final program's objective is to evaluate the reliability and accuracy of interpretation of results from computer-based ultrasonic inservice inspection systems, and to develop guidelines for NRC staff to monitor and evaluate the effectiveness of inservice inspections conducted on nuclear power reactors. This program started in the last quarter of FY89, and the extent of the program was to prepare a work plan for presentation to and approval from a technical advisory group of NRC staff

  16. Maximally reliable Markov chains under energy constraints.

    Science.gov (United States)

    Escola, Sean; Eisele, Michael; Miller, Kenneth; Paninski, Liam

    2009-07-01

    Signal-to-noise ratios in physical systems can be significantly degraded if the outputs of the systems are highly variable. Biological processes for which highly stereotyped signal generations are necessary features appear to have reduced their signal variabilities by employing multiple processing steps. To better understand why this multistep cascade structure might be desirable, we prove that the reliability of a signal generated by a multistate system with no memory (i.e., a Markov chain) is maximal if and only if the system topology is such that the process steps irreversibly through each state, with transition rates chosen such that an equal fraction of the total signal is generated in each state. Furthermore, our result indicates that by increasing the number of states, it is possible to arbitrarily increase the reliability of the system. In a physical system, however, an energy cost is associated with maintaining irreversible transitions, and this cost increases with the number of such transitions (i.e., the number of states). Thus, an infinite-length chain, which would be perfectly reliable, is infeasible. To model the effects of energy demands on the maximally reliable solution, we numerically optimize the topology under two distinct energy functions that penalize either irreversible transitions or incommunicability between states, respectively. In both cases, the solutions are essentially irreversible linear chains, but with upper bounds on the number of states set by the amount of available energy. We therefore conclude that a physical system for which signal reliability is important should employ a linear architecture, with the number of states (and thus the reliability) determined by the intrinsic energy constraints of the system.

  17. Parcels and Land Ownership, Contains parcels, subdivisions, CSMs, Condominiums, Rights of Way and supporting annotation. Data within the City of West Bend are maintained by the City. Some areas are mapped at 1:1200, Published in 2013, 1:2400 (1in=200ft) scale, Washington County Government.

    Data.gov (United States)

    NSGIC Local Govt | GIS Inventory — Parcels and Land Ownership dataset current as of 2013. Contains parcels, subdivisions, CSMs, Condominiums, Rights of Way and supporting annotation. Data within the...

  18. 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.

  19. Prefrontal Neuronal Excitability Maintains Cocaine-Associated Memory During Retrieval

    Directory of Open Access Journals (Sweden)

    James M. Otis

    2018-06-01

    Full Text Available Presentation of drug-associated cues provokes craving and drug seeking, and elimination of these associative memories would facilitate recovery from addiction. Emotionally salient memories are maintained during retrieval, as particular pharmacologic or optogenetic perturbations of memory circuits during retrieval, but not after, can induce long-lasting memory impairments. For example, in rats, inhibition of noradrenergic beta-receptors, which control intrinsic neuronal excitability, in the prelimbic medial prefrontal cortex (PL-mPFC can cause long-term memory impairments that prevent subsequent cocaine-induced reinstatement. The physiologic mechanisms that allow noradrenergic signaling to maintain drug-associated memories during retrieval, however, are unclear. Here we combine patch-clamp electrophysiology ex vivo and behavioral neuropharmacology in vivo to evaluate the mechanisms that maintain drug-associated memory during retrieval in rats. Consistent with previous studies, we find that cocaine experience increases the intrinsic excitability of pyramidal neurons in PL-mPFC. In addition, we now find that this intrinsic plasticity positively predicts the retrieval of a cocaine-induced conditioned place preference (CPP memory, suggesting that such plasticity may contribute to drug-associated memory retrieval. In further support of this, we find that pharmacological blockade of a cAMP-dependent signaling cascade, which allows noradrenergic signaling to elevate neuronal excitability, is required for memory maintenance during retrieval. Thus, inhibition of PL-mPFC neuronal excitability during memory retrieval not only leads to long-term deficits in the memory, but this memory deficit provides protection against subsequent cocaine-induced reinstatement. These data reveal that PL-mPFC intrinsic neuronal excitability maintains a cocaine-associated memory during retrieval and suggest a unique mechanism whereby drug-associated memories could be targeted

  20. Phased mission analysis of maintained systems

    International Nuclear Information System (INIS)

    Terpstra, K.

    1984-09-01

    The present study is devoted to system reliability and is mainly directed to the quantitative evaluation of accident sequences. Event tree methodology and fault tree analysis are applied as basic techniques. It introduces a new methodology for the calculation of the probability of occurrence of an accident sequence. This new methodology takes correctly into account shared equipment dependencies between the different systems present in an accident sequence. Since large and/or complex systems may contain a large number of minimal cut sets (sometimes millions of it), it is not possible as a rule to obtain the exact analytical solution. Therefore, upper and lower bounds for the probability of occurrence of an accident sequence are presented. Calculation results show that this probability is under-estimated if system dependencies are not fully taken into account. The new methodology also offers the possibility to get insight into the degree of dependency between systems based on quantitative calculations. To make the methodology manageable for complex systems, it is implemented in the reliability computer program PHAMISS. This program is written in FORTRAN-IV for the CDC-Cyber 175. PHAMISS is users friendly and has proven to be a fast and efficient program. (Auth.)

  1. Airline experience with reliability-centered maintenance

    International Nuclear Information System (INIS)

    Matteson, T.D.

    1985-01-01

    Reliability-Centered Maintenance is a process for developing preventive maintenance programs. Its concepts evolved from the post WWII experience of the airline community. Its genesis was in a paper by F. Stanley Nowlan and Thomas D. Matteson of United Airlines for the American Institute of Aeronautics and Astronautics in 1967. Its first application was to the Boeing 747. It has subsequently been adopted by the FAA and the Department of Defense and applied to many new transport and military aircraft. Its objective is applicable and effective preventive maintenance and it has proven to be a highly effective replacement for the prior intuitive processes for selective preventive maintenance tasks. It focuses on system functions, functional failures, then dominant failure modes and effects. It then uses a decision tree to classify failure criticality and identify applicable and effective tasks. The result is a program focused on maintaining inherent safety and reliability at minimum cost. (orig.)

  2. Airline experience with reliability-centered maintenance

    Energy Technology Data Exchange (ETDEWEB)

    Matteson, T.D.

    1985-11-01

    Reliability-Centered Maintenance is a process for developing preventive maintenance programs. Its concepts evolved from the post WWII experience of the airline community. Its genesis was in a paper by F. Stanley Nowlan and Thomas D. Matteson of United Airlines for the American Institute of Aeronautics and Astronautics in 1967. Its first application was to the Boeing 747. It has subsequently been adopted by the FAA and the Department of Defense and applied to many new transport and military aircraft. Its objective is applicable and effective preventive maintenance and it has proven to be a highly effective replacement for the prior intuitive processes for selective preventive maintenance tasks. It focuses on system functions, functional failures, then dominant failure modes and effects. It then uses a decision tree to classify failure criticality and identify applicable and effective tasks. The result is a program focused on maintaining inherent safety and reliability at minimum cost. (orig.).

  3. Operations and support cost modeling of conceptual space vehicles

    Science.gov (United States)

    Ebeling, Charles

    1994-01-01

    The University of Dayton is pleased to submit this annual report to the National Aeronautics and Space Administration (NASA) Langley Research Center which documents the development of an operations and support (O&S) cost model as part of a larger life cycle cost (LCC) structure. It is intended for use during the conceptual design of new launch vehicles and spacecraft. This research is being conducted under NASA Research Grant NAG-1-1327. This research effort changes the focus from that of the first two years in which a reliability and maintainability model was developed to the initial development of an operations and support life cycle cost model. Cost categories were initially patterned after NASA's three axis work breakdown structure consisting of a configuration axis (vehicle), a function axis, and a cost axis. A revised cost element structure (CES), which is currently under study by NASA, was used to established the basic cost elements used in the model. While the focus of the effort was on operations and maintenance costs and other recurring costs, the computerized model allowed for other cost categories such as RDT&E and production costs to be addressed. Secondary tasks performed concurrent with the development of the costing model included support and upgrades to the reliability and maintainability (R&M) model. The primary result of the current research has been a methodology and a computer implementation of the methodology to provide for timely operations and support cost analysis during the conceptual design activities.

  4. Experience of maintaining laboratory educational website's sustainability.

    Science.gov (United States)

    Dimenstein, Izak B

    2016-01-01

    Laboratory methodology websites are specialized niche websites. The visibility of a niche website transforms it into an authority site on a particular "niche of knowledge." This article presents some ways in which a laboratory methodology website can maintain its sustainability. The optimal composition of the website includes a basic content, a blog, and an ancillary part. This article discusses experimenting with the search engine optimization query results page. Strategic placement of keywords and even phrases, as well as fragmentation of the post's material, can improve the website's visibility to search engines. Hyperlinks open a chain reaction of additional links and draw attention to the previous posts. Publications in printed periodicals are a substantial part of a niche website presence on the Internet. Although this article explores a laboratory website on the basis of our hands-on expertise maintaining "Grossing Technology in Surgical Pathology" (www.grossing-technology.com) website with a high volume of traffic for more than a decade, the recommendations presented here for developing an authority website can be applied to other professional specialized websites. The authority websites visibility and sustainability are preconditions for aggregating them in a specialized educational laboratory portal.

  5. Maintaining ancient organelles: mitochondrial biogenesis and maturation.

    Science.gov (United States)

    Vega, Rick B; Horton, Julie L; Kelly, Daniel P

    2015-05-22

    The ultrastructure of the cardiac myocyte is remarkable for the high density of mitochondria tightly packed between sarcomeres. This structural organization is designed to provide energy in the form of ATP to fuel normal pump function of the heart. A complex system comprised of regulatory factors and energy metabolic machinery, encoded by both mitochondrial and nuclear genomes, is required for the coordinate control of cardiac mitochondrial biogenesis, maturation, and high-capacity function. This process involves the action of a transcriptional regulatory network that builds and maintains the mitochondrial genome and drives the expression of the energy transduction machinery. This finely tuned system is responsive to developmental and physiological cues, as well as changes in fuel substrate availability. Deficiency of components critical for mitochondrial energy production frequently manifests as a cardiomyopathic phenotype, underscoring the requirement to maintain high respiration rates in the heart. Although a precise causative role is not clear, there is increasing evidence that perturbations in this regulatory system occur in the hypertrophied and failing heart. This review summarizes current knowledge and highlights recent advances in our understanding of the transcriptional regulatory factors and signaling networks that serve to regulate mitochondrial biogenesis and function in the mammalian heart. © 2015 American Heart Association, Inc.

  6. Chewing Maintains Hippocampus-Dependent Cognitive Function.

    Science.gov (United States)

    Chen, Huayue; Iinuma, Mitsuo; Onozuka, Minoru; Kubo, Kin-Ya

    2015-01-01

    Mastication (chewing) is important not only for food intake, but also for preserving and promoting the general health. Recent studies have showed that mastication helps to maintain cognitive functions in the hippocampus, a central nervous system region vital for spatial memory and learning. The purpose of this paper is to review the recent progress of the association between mastication and the hippocampus-dependent cognitive function. There are multiple neural circuits connecting the masticatory organs and the hippocampus. Both animal and human studies indicated that cognitive functioning is influenced by mastication. Masticatory dysfunction is associated with the hippocampal morphological impairments and the hippocampus-dependent spatial memory deficits, especially in elderly. Mastication is an effective behavior for maintaining the hippocampus-dependent cognitive performance, which deteriorates with aging. Therefore, chewing may represent a useful approach in preserving and promoting the hippocampus-dependent cognitive function in older people. We also discussed several possible mechanisms involved in the interaction between mastication and the hippocampal neurogenesis and the future directions for this unique fascinating research.

  7. Maintaining heterokaryosis in pseudo-homothallic fungi.

    Science.gov (United States)

    Grognet, Pierre; Silar, Philippe

    2015-01-01

    Among all the strategies displayed by fungi to reproduce and propagate, some species have adopted a peculiar behavior called pseudo-homothallism. Pseudo-homothallic fungi are true heterothallics, i.e., they need 2 genetically-compatible partners to mate, but they produce self-fertile mycelium in which the 2 different nuclei carrying the compatible mating types are present. This lifestyle not only enables the fungus to reproduce without finding a compatible partner, but also to cross with any mate it may encounter. However, to be fully functional, pseudo-homothallism requires maintaining heterokaryosis at every stage of the life cycle. We recently showed that neither the structure of the mating-type locus nor hybrid-enhancing effect due to the presence of the 2 mating types accounts for the maintenance of heterokaryosis in the pseudo-homothallic fungus P. anserina. In this addendum, we summarize the mechanisms creating heterokaryosis in P. anserina and 2 other well-known pseudo-homothallic fungi, Neurospora tetrasperma and Agaricus bisporus. We also discuss mechanisms potentially involved in maintaining heterokaryosis in these 3 species.

  8. Techniques for increasing the reliability of accelerator control system electronics

    International Nuclear Information System (INIS)

    Utterback, J.

    1993-09-01

    As the physical size of modern accelerators becomes larger and larger, the number of required control system circuit boards increases, and the probability of one of those circuit boards failing while in service also increases. In order to do physics, the experimenters need the accelerator to provide beam reliably with as little down time as possible. With the advent of colliding beams physics, reliability becomes even more important due to the fact that a control system failure can cause the loss of painstakingly produced antiprotons. These facts prove the importance of keeping reliability in mind when designing and maintaining accelerator control system electronics

  9. Reliability test for reactor internals rejuvenation technology

    International Nuclear Information System (INIS)

    Uchiyama, Junichi

    1998-01-01

    41 transparencies were presented on the subject of 'Reliability test for reactor internals rejuvenation technology'. The items presented give an introduction on the management of plant life in Japan and introduce the Nuclear Power Engineering Corporation (NUPEC). The question of what reliability tests for rejuvenation of reactor internals are is discussed in some detail and an outline of each test is given. Altogether six methods to rejuvenate reactor internals are presented, two of which have already been applied to actual plants. The presentation was supported by many detailed drawings and images

  10. Standards in reliability and safety engineering

    International Nuclear Information System (INIS)

    O'Connor, Patrick

    1998-01-01

    This article explains how the highest 'world class' levels of reliability and safety are achieved, by adherence to the basic principles of excellence in design, production, support and maintenance, by continuous improvement, and by understanding that excellence and improvement lead to reduced costs. These principles are contrasted with the methods that have been developed and standardised, particularly military standards for reliability, ISO9000, and safety case regulations. The article concludes that the formal, standardised approaches are misleading and counterproductive, and recommends that they be replaced by a philosophy based on the realities of human performance

  11. Nuclear performance and reliability

    International Nuclear Information System (INIS)

    Rothwell, G.

    1993-01-01

    If fewer forced outages are a sign of improved safety, nuclear power plants have become safer and more productive. There has been a significant improvement in nuclear power plant performance, due largely to a decline in the forced outage rate and a dramatic drop in the average number of forced outages per fuel cycle. If fewer forced outages are a sign of improved safety, nuclear power plants have become safer and more productive over time. To encourage further increases in performance, regulatory incentive schemes should reward reactor operators for improved reliability and safety, as well as for improved performance

  12. The value of reliability

    DEFF Research Database (Denmark)

    Fosgerau, Mogens; Karlström, Anders

    2010-01-01

    We derive the value of reliability in the scheduling of an activity of random duration, such as travel under congested conditions. Using a simple formulation of scheduling utility, we show that the maximal expected utility is linear in the mean and standard deviation of trip duration, regardless...... of the form of the standardised distribution of trip durations. This insight provides a unification of the scheduling model and models that include the standard deviation of trip duration directly as an argument in the cost or utility function. The results generalise approximately to the case where the mean...

  13. Wind turbine reliability : a database and analysis approach.

    Energy Technology Data Exchange (ETDEWEB)

    Linsday, James (ARES Corporation); Briand, Daniel; Hill, Roger Ray; Stinebaugh, Jennifer A.; Benjamin, Allan S. (ARES Corporation)

    2008-02-01

    The US wind Industry has experienced remarkable growth since the turn of the century. At the same time, the physical size and electrical generation capabilities of wind turbines has also experienced remarkable growth. As the market continues to expand, and as wind generation continues to gain a significant share of the generation portfolio, the reliability of wind turbine technology becomes increasingly important. This report addresses how operations and maintenance costs are related to unreliability - that is the failures experienced by systems and components. Reliability tools are demonstrated, data needed to understand and catalog failure events is described, and practical wind turbine reliability models are illustrated, including preliminary results. This report also presents a continuing process of how to proceed with controlling industry requirements, needs, and expectations related to Reliability, Availability, Maintainability, and Safety. A simply stated goal of this process is to better understand and to improve the operable reliability of wind turbine installations.

  14. Software reliability growth model for safety systems of nuclear reactor

    International Nuclear Information System (INIS)

    Thirugnana Murthy, D.; Murali, N.; Sridevi, T.; Satya Murty, S.A.V.; Velusamy, K.

    2014-01-01

    The demand for complex software systems has increased more rapidly than the ability to design, implement, test, and maintain them, and the reliability of software systems has become a major concern for our, modern society.Software failures have impaired several high visibility programs in space, telecommunications, defense and health industries. Besides the costs involved, it setback the projects. The ways of quantifying it and using it for improvement and control of the software development and maintenance process. This paper discusses need for systematic approaches for measuring and assuring software reliability which is a major share of project development resources. It covers the reliability models with the concern on 'Reliability Growth'. It includes data collection on reliability, statistical estimation and prediction, metrics and attributes of product architecture, design, software development, and the operational environment. Besides its use for operational decisions like deployment, it includes guiding software architecture, development, testing and verification and validation. (author)

  15. Interactive reliability assessment using an integrated reliability data bank

    International Nuclear Information System (INIS)

    Allan, R.N.; Whitehead, A.M.

    1986-01-01

    The logical structure, techniques and practical application of a computer-aided technique based on a microcomputer using floppy disc Random Access Files is described. This interactive computational technique is efficient if the reliability prediction program is coupled directly to a relevant source of data to create an integrated reliability assessment/reliability data bank system. (DG)

  16. Microprocessor hardware reliability

    Energy Technology Data Exchange (ETDEWEB)

    Wright, R I

    1982-01-01

    Microprocessor-based technology has had an impact in nearly every area of industrial electronics and many applications have important safety implications. Microprocessors are being used for the monitoring and control of hazardous processes in the chemical, oil and power generation industries, for the control and instrumentation of aircraft and other transport systems and for the control of industrial machinery. Even in the field of nuclear reactor protection, where designers are particularly conservative, microprocessors are used to implement certain safety functions and may play increasingly important roles in protection systems in the future. Where microprocessors are simply replacing conventional hard-wired control and instrumentation systems no new hazards are created by their use. In the field of robotics, however, the microprocessor has opened up a totally new technology and with it has created possible new and as yet unknown hazards. The paper discusses some of the design and manufacturing techniques which may be used to enhance the reliability of microprocessor based systems and examines the available reliability data on lsi/vlsi microcircuits. 12 references.

  17. Supply chain reliability modelling

    Directory of Open Access Journals (Sweden)

    Eugen Zaitsev

    2012-03-01

    Full Text Available Background: Today it is virtually impossible to operate alone on the international level in the logistics business. This promotes the establishment and development of new integrated business entities - logistic operators. However, such cooperation within a supply chain creates also many problems related to the supply chain reliability as well as the optimization of the supplies planning. The aim of this paper was to develop and formulate the mathematical model and algorithms to find the optimum plan of supplies by using economic criterion and the model for the probability evaluating of non-failure operation of supply chain. Methods: The mathematical model and algorithms to find the optimum plan of supplies were developed and formulated by using economic criterion and the model for the probability evaluating of non-failure operation of supply chain. Results and conclusions: The problem of ensuring failure-free performance of goods supply channel analyzed in the paper is characteristic of distributed network systems that make active use of business process outsourcing technologies. The complex planning problem occurring in such systems that requires taking into account the consumer's requirements for failure-free performance in terms of supply volumes and correctness can be reduced to a relatively simple linear programming problem through logical analysis of the structures. The sequence of the operations, which should be taken into account during the process of the supply planning with the supplier's functional reliability, was presented.

  18. [Maintaining solidarity: is mutuality the solution?].

    Science.gov (United States)

    Gevers, J K M; Ploem, M C

    2013-01-01

    Solidarity is essentially the willingness to contribute to the community and its demands, which may even involve contributing more than one is expecting to receive. Another principle is mutuality: this refers to a balance between rights and obligations or between mutual obligations. In its advisory document 'The importance of mutuality......solidarity takes work!', The Dutch Council for Public Health and Health Care underlines the importance of ensuring solidarity within the Dutch health care system, e.g. by encouraging patients to take responsibility for their own health, possibly by introducing elements of mutuality. In our contribution, we comment on the Council's advice. Although we fully agree with the overall conclusion that solidarity should be maintained within the system, we do not see how the introduction of increased mutuality will contribute to this goal.

  19. Maintaining human productivity during Mars transit

    Science.gov (United States)

    Statler, Irving C.; Billings, Charles E.

    1989-01-01

    This paper addresses the special nature of the human-machine relationship during a trip to Mars. In particular, the potential for monotony and boredom during a long-duration space voyage and the effect on motivation and productivity can be important considerations to the health and welfare of the crew. For the voyage to Mars, a design may be considered that will purposefully maintain some level of workload for the crew as a preventive measure for the deterioration of productivity that comes with boredom. This paper speculates on these considerations, on the appropriate level of workload for maximum productivity, and on what might be done during the mission to alleviate the problems caused by monotony and boredom.

  20. Heartwarming memories: Nostalgia maintains physiological comfort.

    Science.gov (United States)

    Zhou, Xinyue; Wildschut, Tim; Sedikides, Constantine; Chen, Xiaoxi; Vingerhoets, Ad J J M

    2012-08-01

    Nostalgia, a sentimental longing or wistful affection for the past, is a predominantly positive and social emotion. Recent evidence suggests that nostalgia maintains psychological comfort. Here, we propose, and document in five methodologically diverse studies, a broader homeostatic function for nostalgia that also encompasses the maintenance of physiological comfort. We show that nostalgia--an emotion with a strong connotation of warmth--is triggered by coldness. Participants reported stronger nostalgia on colder (vs. warmer) days and in a cold (vs. neutral or warm) room. Nostalgia, in turn, modulates the interoceptive feeling of temperature. Higher levels of music-evoked nostalgia predicted increased physical warmth, and participants who recalled a nostalgic (vs. ordinary autobiographical) event perceived ambient temperature as higher. Finally, and consistent with the close central nervous system integration of temperature and pain sensations, participants who recalled a nostalgic (vs. ordinary autobiographical) event evinced greater tolerance to noxious cold.

  1. Maintaining and troubleshooting your 3D printer

    CERN Document Server

    Bell, Charles

    2014-01-01

    Maintaining and Troubleshooting Your 3D Printer by Charles Bell is your guide to keeping your 3D printer running through preventive maintenance, repair, and diagnosing and solving problems in 3D printing. If you've bought or built a 3D printer such as a MakerBot only to be confounded by jagged edges, corner lift, top layers that aren't solid, or any of a myriad of other problems that plague 3D printer enthusiasts, then here is the book to help you get past all that and recapture the joy of creative fabrication. The book also includes valuable tips for builders and those who want to modify the

  2. Balancing selection maintains cryptic colour morphs.

    Science.gov (United States)

    Wellenreuther, Maren

    2017-11-01

    Animals display incredibly diverse colour patterns, a testament to evolution's endless innovation in shaping life. In many species, the interplay between males and females in the pursuit of mates has driven the evolution of a myriad of colour forms, from the flashy peacock tail feathers to the tiniest colour markings in damselflies. In others, colour provides crypsis by allowing to blend into the background and to escape the eyes of predators. While the obvious benefits of this dazzling diversity for reproduction and survival seem straightforward, its maintenance is not. Theory predicts that genetic drift and various forms of selection reduce variation over time, making the persistence of colour variants over generations a puzzle. In this issue of Molecular Ecology, Lindtke et al. () study the cryptic colour morphs of Timema cristinae walking sticks to shed light on the genetic architecture and mechanisms that allow colour polymorphism maintenance over long timescales. By combining genome-wide data with phenotyping information from natural populations, they were able to map the green and melanistic colour to one genomic region with highly reduced effective recombination rate between two main chromosomal variants, consistent with an inversion polymorphism. These two main chromosomal variants showed geographically widespread heterozygote excess, and genomic signatures consistent with long-term balancing selection. A younger chromosomal variant was detected for the third morph, the green-striped colour morphs, in the same genomic regions as the melanistic and the green-unstriped morphs. Together, these results suggest that the genetic architecture of cryptic T. cristinae morphs is caused by nonrecombining genomic blocks that have been maintained over extended time periods by balancing selection making this study one of the few available empirical examples documenting that balancing selection of various forms may play an important role in maintaining adaptive genetic

  3. Transit ridership, reliability, and retention.

    Science.gov (United States)

    2008-10-01

    This project explores two major components that affect transit ridership: travel time reliability and rider : retention. It has been recognized that transit travel time reliability may have a significant impact on : attractiveness of transit to many ...

  4. Travel reliability inventory for Chicago.

    Science.gov (United States)

    2013-04-01

    The overarching goal of this research project is to enable state DOTs to document and monitor the reliability performance : of their highway networks. To this end, a computer tool, TRIC, was developed to produce travel reliability inventories from : ...

  5. Seeking high reliability in primary care: Leadership, tools, and organization.

    Science.gov (United States)

    Weaver, Robert R

    2015-01-01

    Leaders in health care increasingly recognize that improving health care quality and safety requires developing an organizational culture that fosters high reliability and continuous process improvement. For various reasons, a reliability-seeking culture is lacking in most health care settings. Developing a reliability-seeking culture requires leaders' sustained commitment to reliability principles using key mechanisms to embed those principles widely in the organization. The aim of this study was to examine how key mechanisms used by a primary care practice (PCP) might foster a reliability-seeking, system-oriented organizational culture. A case study approach was used to investigate the PCP's reliability culture. The study examined four cultural artifacts used to embed reliability-seeking principles across the organization: leadership statements, decision support tools, and two organizational processes. To decipher their effects on reliability, the study relied on observations of work patterns and the tools' use, interactions during morning huddles and process improvement meetings, interviews with clinical and office staff, and a "collective mindfulness" questionnaire. The five reliability principles framed the data analysis. Leadership statements articulated principles that oriented the PCP toward a reliability-seeking culture of care. Reliability principles became embedded in the everyday discourse and actions through the use of "problem knowledge coupler" decision support tools and daily "huddles." Practitioners and staff were encouraged to report unexpected events or close calls that arose and which often initiated a formal "process change" used to adjust routines and prevent adverse events from recurring. Activities that foster reliable patient care became part of the taken-for-granted routine at the PCP. The analysis illustrates the role leadership, tools, and organizational processes play in developing and embedding a reliable-seeking culture across an

  6. Safety, reliability and worker satisfaction during organizational change

    NARCIS (Netherlands)

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

    2014-01-01

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

  7. Reliability demonstration of imaging surveillance systems

    International Nuclear Information System (INIS)

    Sheridan, T.F.; Henderson, J.T.; MacDiarmid, P.R.

    1979-01-01

    Security surveillance systems which employ closed circuit television are being deployed with increasing frequency for the protection of property and other valuable assets. A need exists to demonstrate the reliability of such systems before their installation to assure that the deployed systems will operate when needed with only the scheduled amount of maintenance and support costs. An approach to the reliability demonstration of imaging surveillance systems which employ closed circuit television is described. Failure definitions based on industry television standards and imaging alarm assessment criteria for surveillance systems are discussed. Test methods which allow 24 hour a day operation without the need for numerous test scenarios, test personnel and elaborate test facilities are presented. Existing reliability demonstration standards are shown to apply which obviate the need for elaborate statistical tests. The demonstration methods employed are shown to have applications in other types of imaging surveillance systems besides closed circuit television

  8. Vestibular feedback maintains reaching accuracy during body movement

    Science.gov (United States)

    Reynolds, Raymond F.

    2016-01-01

    Key points Reaching movements can be perturbed by vestibular input, but the function of this response is unclear.Here, we applied galvanic vestibular stimulation concurrently with real body movement while subjects maintained arm position either fixed in space or fixed with respect to their body.During the fixed‐in‐space conditions, galvanic vestibular stimulation caused large changes in arm trajectory consistent with a compensatory response to maintain upper‐limb accuracy in the face of body movement.Galvanic vestibular stimulation responses were absent during the body‐fixed task, demonstrating task dependency in vestibular control of the upper limb.The results suggest that the function of vestibular‐evoked arm movements is to maintain the accuracy of the upper limb during unpredictable body movement, but only when reaching in an earth‐fixed reference frame. Abstract When using our arms to interact with the world, unintended body motion can introduce movement error. A mechanism that could detect and compensate for such motion would be beneficial. Observations of arm movements evoked by vestibular stimulation provide some support for this mechanism. However, the physiological function underlying these artificially evoked movements is unclear from previous research. For such a mechanism to be functional, it should operate only when the arm is being controlled in an earth‐fixed rather than a body‐fixed reference frame. In the latter case, compensation would be unnecessary and even deleterious. To test this hypothesis, subjects were gently rotated in a chair while being asked to maintain their outstretched arm pointing towards either earth‐fixed or body‐fixed memorized targets. Galvanic vestibular stimulation was applied concurrently during rotation to isolate the influence of vestibular input, uncontaminated by inertial factors. During the earth‐fixed task, galvanic vestibular stimulation produced large polarity‐dependent corrections in arm

  9. Evaluation of mobile ad hoc network reliability using propagation-based link reliability model

    International Nuclear Information System (INIS)

    Padmavathy, N.; Chaturvedi, Sanjay K.

    2013-01-01

    A wireless mobile ad hoc network (MANET) is a collection of solely independent nodes (that can move randomly around the area of deployment) making the topology highly dynamic; nodes communicate with each other by forming a single hop/multi-hop network and maintain connectivity in decentralized manner. MANET is modelled using geometric random graphs rather than random graphs because the link existence in MANET is a function of the geometric distance between the nodes and the transmission range of the nodes. Among many factors that contribute to the MANET reliability, the reliability of these networks also depends on the robustness of the link between the mobile nodes of the network. Recently, the reliability of such networks has been evaluated for imperfect nodes (transceivers) with binary model of communication links based on the transmission range of the mobile nodes and the distance between them. However, in reality, the probability of successful communication decreases as the signal strength deteriorates due to noise, fading or interference effects even up to the nodes' transmission range. Hence, in this paper, using a propagation-based link reliability model rather than a binary-model with nodes following a known failure distribution to evaluate the network reliability (2TR m , ATR m and AoTR m ) of MANET through Monte Carlo Simulation is proposed. The method is illustrated with an application and some imperative results are also presented

  10. Bootstrapping and Maintaining Trust in the Cloud

    Science.gov (United States)

    2016-12-01

    such as going off the certificate’s common name (hostname). 6https://www.packer.io/ 7https://www.chef.io/ chef / Node Registrar ID,AIKpub,EKpub EncEK(Ke...and libvirt to support the creation of companion vTPM Xen domains for each user created instance. We link the OpenStack UUID to the keylime provider

  11. Coping under pressure: Strategies for maintaining confidence ...

    African Journals Online (AJOL)

    Soccer coaches face a number of challenges, frustrations, conflicts and tensions, the enormity of which is often underestimated. This notion is supported by the description of coaching as a perilous occupation in which coaches experience pressures like stress, conflict and tension, media pressure and intrusions into family ...

  12. 2017 NREL Photovoltaic Reliability Workshop

    Energy Technology Data Exchange (ETDEWEB)

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

    2017-08-15

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

  13. Maintaining Work: The Influence of Child Care Subsidies on Child Care-Related Work Disruptions

    Science.gov (United States)

    Forry, Nicole D.; Hofferth, Sandra L.

    2011-01-01

    With the passage of welfare reform, support for low-income parents to not only obtain but also maintain work has become imperative. The role of child care subsidies in supporting parents' job tenure has received little attention in the literature. This article examines the association between receiving a child care subsidy and experiencing a child…

  14. Business of reliability

    Science.gov (United States)

    Engel, Pierre

    1999-12-01

    The presentation is organized around three themes: (1) The decrease of reception equipment costs allows non-Remote Sensing organization to access a technology until recently reserved to scientific elite. What this means is the rise of 'operational' executive agencies considering space-based technology and operations as a viable input to their daily tasks. This is possible thanks to totally dedicated ground receiving entities focusing on one application for themselves, rather than serving a vast community of users. (2) The multiplication of earth observation platforms will form the base for reliable technical and financial solutions. One obstacle to the growth of the earth observation industry is the variety of policies (commercial versus non-commercial) ruling the distribution of the data and value-added products. In particular, the high volume of data sales required for the return on investment does conflict with traditional low-volume data use for most applications. Constant access to data sources supposes monitoring needs as well as technical proficiency. (3) Large volume use of data coupled with low- cost equipment costs is only possible when the technology has proven reliable, in terms of application results, financial risks and data supply. Each of these factors is reviewed. The expectation is that international cooperation between agencies and private ventures will pave the way for future business models. As an illustration, the presentation proposes to use some recent non-traditional monitoring applications, that may lead to significant use of earth observation data, value added products and services: flood monitoring, ship detection, marine oil pollution deterrent systems and rice acreage monitoring.

  15. Maintaining nuclear competence and expertise in Japan

    International Nuclear Information System (INIS)

    Fujii, Y.

    2004-01-01

    The fundamental law of atomic energy, which strictly restricts the application of atomic energy to the peaceful use, was established in 1955 in Japan. Since then, during the past five decades, great efforts were made to develop atomic energy. So far 52 units of light water reactors, 29 BWRs and 23 PWRs, have been built and in operation, 5 units are under construction and 6 units are planed to be built. Total capacity of presently operated NPPs amounts to 45.7 Gwe and the nuclear energy shares 30 % of the total electricity generation in Japan. During the past 10 years, several accidents occur in the nuclear facilities of electric power companies, and JNC ( previously PNC ). In spite of these accidents, including the accident of Kansai Electric Power Co. this year, the important role of nuclear energy to sustain the lives of people in Japan is intact. In the nuclear energy projection, the construction of NPPs continues till 2010. Thereafter reconstructions of NPPs are foreseen in the decade 2030's for the replacement of present NPPs in operation after 60 years services. Attention has been directed to the technology preservation: how competence and expertise of nuclear engineering can be maintained till the next period of replacement construction, in particular, the period between years 2010 and 2030. The present paper reviews the status of nuclear engineering programs in universities in Japan. The nuclear education programs started in graduate schools in 1957 and expanded to undergraduate schools of major national universities. Presently nine universities are providing systematic nuclear education programs in their graduate schools, although the corresponding department have been changed their names from 'nuclear' to more broaden terms of 'quantum', 'energy' and 'system' in several universities. Under the conditions of shrinking nuclear industries, how to maintain the present education system is seriously concerned matter in the universities. The present paper

  16. SGHWR fuel performance, safety and reliability

    International Nuclear Information System (INIS)

    Pickman, D.O.; Inglis, G.H.

    1977-05-01

    The design principles involved in fuel pins and elements need to take account of the sometimes conflicting requirements of safety and reliability. The principal factors involved in this optimisation are discussed and it is shown from fuel irradiation experience in the Winfrith SGHWR that the necessary bias towards safety has not resulted in a reliability level lower than that shown by other successful water reactor designs. Reliability has important economic implications. By a detailed evaluation of SGHWR fuel defects it is shown that very few defects can be shown to be related to design, rating, or burn-up. This demonstrates that economic aspects have not over-ridden necessary criteria that most be met to achieve the desirable reliability level. It is possible that large scale experience on SGHWR fuel may eventually demonstrate that the balance is too much in favour of reliability and consideration may be given to whether design changes favouring economy could be achieved without compromising safety. The safety criteria applied to SGHWR fuel are designed to avoid any possibility of a temperature runaway in any credible accident situation. the philosophy and supporting experimental work programme are outlines and the fuel design features which particularly contribute to maximising safety margins are outlined. Reference is made to the new 60-pin fuel element to be used in the commercial SGHWRs and to its comparison in design and performance aspects with the 36-pin element that has been used to date in the Winfrith SGHWR. (author)

  17. Reliability and accuracy of Crystaleye spectrophotometric system.

    Science.gov (United States)

    Chen, Li; Tan, Jian Guo; Zhou, Jian Feng; Yang, Xu; Du, Yang; Wang, Fang Ping

    2010-01-01

    to develop an in vitro shade-measuring model to evaluate the reliability and accuracy of the Crystaleye spectrophotometric system, a newly developed spectrophotometer. four shade guides, VITA Classical, VITA 3D-Master, Chromascop and Vintage Halo NCC, were measured with the Crystaleye spectrophotometer in a standardised model, ten times for 107 shade tabs. The shade-matching results and the CIE L*a*b* values of the cervical, body and incisal regions for each measurement were automatically analysed using the supporting software. Reliability and accuracy were calculated for each shade tab both in percentage and in colour difference (ΔE). Difference was analysed by one-way ANOVA in the cervical, body and incisal regions. range of reliability was 88.81% to 98.97% and 0.13 to 0.24 ΔE units, and that of accuracy was 44.05% to 91.25% and 1.03 to 1.89 ΔE units. Significant differences in reliability and accuracy were found between the body region and the cervical and incisal regions. Comparisons made among regions and shade guides revealed that evaluation in ΔE was prone to disclose the differences. measurements with the Crystaleye spectrophotometer had similar, high reliability in different shade guides and regions, indicating predictable repeated measurements. Accuracy in the body region was high and less variable compared with the cervical and incisal regions.

  18. PSA applications and piping reliability analysis: where do we stand?

    International Nuclear Information System (INIS)

    Lydell, B.O.Y.

    1997-01-01

    This reviews a recently proposed framework for piping reliability analysis. The framework was developed to promote critical interpretations of operational data on pipe failures, and to support application-specific-parameter estimation

  19. Reliability and construct validity for scale of rejection of Christianity.

    Science.gov (United States)

    Robbins, Mandy; Francis, Leslie J; Bradford, Amanda

    2003-02-01

    A sample of 16 male and 30 female undergraduates completed the Greer and Francis Scale of Rejection of Christianity. The data support the internal consistency reliability and construct validity of the scale for this sample.

  20. Reliability and Probabilistic Risk Assessment - How They Play Together

    Science.gov (United States)

    Safie, Fayssal M.; Stutts, Richard; Huang, Zhaofeng

    2015-01-01

    The objective of this presentation is to discuss the PRA process and the reliability engineering discipline, their differences and similarities, and how they are used as complimentary analyses to support design and flight decisions.

  1. Electronics reliability calculation and design

    CERN Document Server

    Dummer, Geoffrey W A; Hiller, N

    1966-01-01

    Electronics Reliability-Calculation and Design provides an introduction to the fundamental concepts of reliability. The increasing complexity of electronic equipment has made problems in designing and manufacturing a reliable product more and more difficult. Specific techniques have been developed that enable designers to integrate reliability into their products, and reliability has become a science in its own right. The book begins with a discussion of basic mathematical and statistical concepts, including arithmetic mean, frequency distribution, median and mode, scatter or dispersion of mea

  2. Sociable Robots Through Self-Maintained Energy

    Directory of Open Access Journals (Sweden)

    Trung Dung Ngo

    2006-12-01

    Full Text Available Research of autonomous mobile robots has mostly emphasized interaction and coordination that are natually inspired from biological behavior of birds, insects, and fish: flocking, foraging, collecting, and sharing. However, most research has been only focused on autonomous behaviors in order to perform robots like animals, whereas it is lacked of determinant to those behaviours: energy. Approaching to clusted amimal and the higher, collective and sharing food among individuals are major activity to keep society being. This paper issues an approach to sociable robots using self-maintained energy in cooperative mobile robots, which is dominantly inspired from swarm behavior of collecting and sharing food of honey-bee and ant. Autonomous mobile robots are usually equipped with a finite energy, thus they can operate in a finite time. To overcome the finitude, we describe practical deployment of mobile robots that are capable of carrying and exchanging fuel to other robots. Mechanism implementation including modular hardware and control architecture to demonstrate the capabicities of the approach is presented. Subsequently, the battery exchange algorithm basically based on probabilistic modeling of total energy on each robot located in its local vicinity is described. The paper is concluded with challenging works of chain of mobile robots, rescue, repair, and relation of heterogeneous robots.

  3. Sociable Robots through Self-maintained Energy

    Directory of Open Access Journals (Sweden)

    Henrik Schioler

    2008-11-01

    Full Text Available Research of autonomous mobile robots has mostly emphasized interaction and coordination that are natually inspired from biological behavior of birds, insects, and fish: flocking, foraging, collecting, and sharing. However, most research has been only focused on autonomous behaviors in order to perform robots like animals, whereas it is lacked of determinant to those behaviours: energy. Approaching to clusted amimal and the higher, collective and sharing food among individuals are major activity to keep society being. This paper issues an approach to sociable robots using self-maintained energy in cooperative mobile robots, which is dominantly inspired from swarm behavior of collecting and sharing food of honey-bee and ant. Autonomous mobile robots are usually equipped with a finite energy, thus they can operate in a finite time. To overcome the finitude, we describe practical deployment of mobile robots that are capable of carrying and exchanging fuel to other robots. Mechanism implementation including modular hardware and control architecture to demonstrate the capabicities of the approach is presented. Subsequently, the battery exchange algorithm basically based on probabilistic modeling of total energy on each robot located in its local vicinity is described. The paper is concluded with challenging works of chain of mobile robots, rescue, repair, and relation of heterogeneous robots.

  4. State Support of Domestic Production

    Energy Technology Data Exchange (ETDEWEB)

    Amy Wright

    2007-12-30

    This project was developed in response to a cooperative agreement offering by the U.S. Department of Energy (DOE) and the National Energy Technology Laboratory (NETL) under the State Support of Domestic Production DE-FC26-04NT15456. The Interstate Oil and Gas Compact Commission (IOGCC) performed efforts in support of State programs related to the security, reliability and growth if our nation's domestic production of oil and natural gas. The project objectives were to improve the States ability to monitor the security of oil and gas operations; to maximize the production of domestic oil and natural gas thereby minimizing the threat to national security posed by interruptions in energy imports; to assist States in developing and maintaining high standards of environmental protection; to assist in addressing issues that limit the capacity of the industry; to promote the deployment of the appropriate application of technology for regulatory efficiency; and to inform the public about emerging energy issues.

  5. Developing Predictive Maintenance Expertise to Improve Plant Equipment Reliability

    International Nuclear Information System (INIS)

    Wurzbach, Richard N.

    2002-01-01

    On-line equipment condition monitoring is a critical component of the world-class production and safety histories of many successful nuclear plant operators. From addressing availability and operability concerns of nuclear safety-related equipment to increasing profitability through support system reliability and reduced maintenance costs, Predictive Maintenance programs have increasingly become a vital contribution to the maintenance and operation decisions of nuclear facilities. In recent years, significant advancements have been made in the quality and portability of many of the instruments being used, and software improvements have been made as well. However, the single most influential component of the success of these programs is the impact of a trained and experienced team of personnel putting this technology to work. Changes in the nature of the power generation industry brought on by competition, mergers, and acquisitions, has taken the historically stable personnel environment of power generation and created a very dynamic situation. As a result, many facilities have seen a significant turnover in personnel in key positions, including predictive maintenance personnel. It has become the challenge for many nuclear operators to maintain the consistent contribution of quality data and information from predictive maintenance that has become important in the overall equipment decision process. These challenges can be met through the implementation of quality training to predictive maintenance personnel and regular updating and re-certification of key technology holders. The use of data management tools and services aid in the sharing of information across sites within an operating company, and with experts who can contribute value-added data management and analysis. The overall effectiveness of predictive maintenance programs can be improved through the incorporation of newly developed comprehensive technology training courses. These courses address the use of

  6. Mathematical reliability an expository perspective

    CERN Document Server

    Mazzuchi, Thomas; Singpurwalla, Nozer

    2004-01-01

    In this volume consideration was given to more advanced theoretical approaches and novel applications of reliability to ensure that topics having a futuristic impact were specifically included. Topics like finance, forensics, information, and orthopedics, as well as the more traditional reliability topics were purposefully undertaken to make this collection different from the existing books in reliability. The entries have been categorized into seven parts, each emphasizing a theme that seems poised for the future development of reliability as an academic discipline with relevance. The seven parts are networks and systems; recurrent events; information and design; failure rate function and burn-in; software reliability and random environments; reliability in composites and orthopedics, and reliability in finance and forensics. Embedded within the above are some of the other currently active topics such as causality, cascading, exchangeability, expert testimony, hierarchical modeling, optimization and survival...

  7. An economically reliable scenario

    International Nuclear Information System (INIS)

    Anon.

    1996-01-01

    Mister Benjamin Dessus, director of the Ecotech programme at the Cnrs and author of the Noe scenario, describes his propositions for energy prospective, supported by an economic analysis. He advocates the energy diversification and the use of renewable energies. (N.C.). 1 ref., 1 tab

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

    Science.gov (United States)

    Chassin, Mark R; Loeb, Jerod M

    2013-09-01

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

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

    Science.gov (United States)

    Chassin, Mark R; Loeb, Jerod M

    2013-01-01

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

  10. How to keep punishment to maintain cooperation: Introducing social vaccine

    Science.gov (United States)

    Yamamoto, Hitoshi; Okada, Isamu

    2016-02-01

    Although there is much support for the punishment system as a sophisticated approach to resolving social dilemmas, more than a few researchers have also pointed out the limitations of such an approach. Second-order free riding is a serious issue facing the punishment system. Various pioneering works have suggested that an anti-social behavior or noise stemming from a mutation may, surprisingly, be helpful for avoiding second-order freeloaders. In this work, we show through mathematical analysis and an agent-based simulation of a model extending the meta-norms game that the coercive introduction of a small number of non-cooperators can maintain a cooperative regime robustly. This paradoxical idea was inspired by the effect of a vaccine, which is a weakened pathogen injected into a human body to create antibodies and ward off infection by that pathogen. Our expectation is that the coercive introduction of a few defectors, i.e., a social vaccine, will help maintain a highly cooperative regime because it will ensure that the punishment system works.

  11. Sister chromosome pairing maintains heterozygosity in parthenogenetic lizards.

    Science.gov (United States)

    Lutes, Aracely A; Neaves, William B; Baumann, Diana P; Wiegraebe, Winfried; Baumann, Peter

    2010-03-11

    Although bisexual reproduction has proven to be highly successful, parthenogenetic all-female populations occur frequently in certain taxa, including the whiptail lizards of the genus Aspidoscelis. Allozyme analysis revealed a high degree of fixed heterozygosity in these parthenogenetic species, supporting the view that they originated from hybridization events between related sexual species. It has remained unclear how the meiotic program is altered to produce diploid eggs while maintaining heterozygosity. Here we show that meiosis commences with twice the number of chromosomes in parthenogenetic versus sexual species, a mechanism that provides the basis for generating gametes with unreduced chromosome content without fundamental deviation from the classic meiotic program. Our observation of synaptonemal complexes and chiasmata demonstrate that a typical meiotic program occurs and that heterozygosity is not maintained by bypassing recombination. Instead, fluorescent in situ hybridization probes that distinguish between homologues reveal that bivalents form between sister chromosomes, the genetically identical products of the first of two premeiotic replication cycles. Sister chromosome pairing provides a mechanism for the maintenance of heterozygosity, which is critical for offsetting the reduced fitness associated with the lack of genetic diversity in parthenogenetic species.

  12. Hamilton's inclusive fitness maintains heritable altruism polymorphism through rb = c.

    Science.gov (United States)

    Wang, Changcao; Lu, Xin

    2018-02-20

    How can altruism evolve or be maintained in a selfish world? Hamilton's rule shows that the former process will occur when rb > c -the benefits to the recipients of an altruistic act b , weighted by the relatedness between the social partners r , exceed the costs to the altruists c -drives altruistic genotypes spreading against nonaltruistic ones. From this rule, we infer that altruistic genotypes will persist in a population by forming a stable heritable polymorphism with nonaltruistic genotypes if rb = c makes inclusive fitness of the two morphs equal. We test this prediction using the data of 12 years of study on a cooperatively breeding bird, the Tibetan ground tit Pseudopodoces humilis , where helping is performed by males only and kin-directed. Individual variation in ever acting as a helper was heritable ( h 2 = 0.47), and the resultant altruism polymorphism remained stable as indicated by low-level annual fluctuation of the percentage of helpers among all adult males (24-28%). Helpers' indirect fitness gains from increased lifetime reproductive success of related breeders statistically fully compensated for their lifetime direct fitness losses, suggesting that rb = c holds. While our work provides a fundamental support for Hamilton's idea, it highlights the equivalent inclusive fitness returns to altruists and nonaltruists mediated by rb = c as a theoretically and realistically important mechanism to maintain social polymorphism.

  13. Proceedings of the workshop on reliability data collection

    International Nuclear Information System (INIS)

    1999-01-01

    The main purpose of the Workshop was to provide a forum for exchanging information and experience on Reliability Data Collection and analysis to support Living Probabilistic Safety Assessments (LPSA). The Workshop is divided into four sessions which titles are: Session 1: Reliability Data - Database Systems (3 papers), Session 2: Reliability Data Collection for PSA (5 papers), Session 3: NPP Data Collection (3 papers), Session 4: Reliability Data Assessment (Part 1: General - 2 papers; Part 2: CCF - 2 papers; Part 3: Reactor Protection Systems / External Event Data - 2 papers; Part 4: Human Errors - 2 papers)

  14. Of plants and reliability

    International Nuclear Information System (INIS)

    Schneider Horst

    2009-01-01

    Behind the political statements made about the transformer event at the Kruemmel nuclear power station (KKK) in the summer of 2009 there are fundamental issues of atomic law. Pursuant to Articles 20 and 28 of its Basic Law, Germany is a state in which the rule of law applies. Consequently, the aspects of atomic law associated with the incident merit a closer look, all the more so as the items concerned have been known for many years. Important aspects in the debate about the Kruemmel nuclear power plant are the fact that the transformer is considered part of the nuclear power station under atomic law and thus a ''plant'' subject to surveillance by the nuclear regulatory agencies, on the one hand, and the reliability under atomic law of the operator and the executive personnel responsible, on the other hand. Both ''plant'' and ''reliability'' are terms focusing on nuclear safety. Hence the question to what extent safety was affected in the Kruemmel incident. The classification of the event as 0 = no or only a very slight safety impact on the INES scale (INES = International Nuclear Event Scale) should not be used to put aside the safety issue once and for all. Points of fact and their technical significance must be considered prior to any legal assessment. Legal assessments and regulations are associated with facts and circumstances. Any legal examination is based on the facts as determined and elucidated. Any other procedure would be tantamount to an inadmissible legal advance conviction. Now, what is the position of political statements, i.e. political assessments and political responsibility? If everything is done the correct way, they come at the end, after exploration of the facts and evaluation under applicable law. Sometimes things are handled differently, with consequences which are not very helpful. In the light of the provisions about the rule of law as laid down in the Basic Law, the new federal government should be made to observe the proper sequence of

  15. Reliability: How much is it worth? Beyond its estimation or prediction, the (net) present value of reliability

    International Nuclear Information System (INIS)

    Saleh, J.H.; Marais, K.

    2006-01-01

    In this article, we link an engineering concept, reliability, to a financial and managerial concept, net present value, by exploring the impact of a system's reliability on its revenue generation capability. The framework here developed for non-repairable systems quantitatively captures the value of reliability from a financial standpoint. We show that traditional present value calculations of engineering systems do not account for system reliability, thus over-estimate a system's worth and can therefore lead to flawed investment decisions. It is therefore important to involve reliability engineers upfront before investment decisions are made in technical systems. In addition, the analyses here developed help designers identify the optimal level of reliability that maximizes a system's net present value-the financial value reliability provides to the system minus the cost to achieve this level of reliability. Although we recognize that there are numerous considerations driving the specification of an engineering system's reliability, we contend that the financial analysis of reliability here developed should be made available to decision-makers to support in part, or at least be factored into, the system reliability specification

  16. Designing Glass Panels for Economy and Reliability

    Science.gov (United States)

    Moore, D. M.

    1983-01-01

    Analytical method determines probability of failure of rectangular glass plates subjected to uniformly distributed loads such as those from wind, earthquake, snow, and deadweight. Developed as aid in design of protective glass covers for solar-cell arrays and solar collectors, method is also useful in estimating the reliability of large windows in buildings exposed to high winds and is adapted to nonlinear stress analysis of simply supported plates of any elastic material.

  17. Maintaining homeostasis by decision-making.

    Directory of Open Access Journals (Sweden)

    Christoph W Korn

    2015-05-01

    Full Text Available Living organisms need to maintain energetic homeostasis. For many species, this implies taking actions with delayed consequences. For example, humans may have to decide between foraging for high-calorie but hard-to-get, and low-calorie but easy-to-get food, under threat of starvation. Homeostatic principles prescribe decisions that maximize the probability of sustaining appropriate energy levels across the entire foraging trajectory. Here, predictions from biological principles contrast with predictions from economic decision-making models based on maximizing the utility of the endpoint outcome of a choice. To empirically arbitrate between the predictions of biological and economic models for individual human decision-making, we devised a virtual foraging task in which players chose repeatedly between two foraging environments, lost energy by the passage of time, and gained energy probabilistically according to the statistics of the environment they chose. Reaching zero energy was framed as starvation. We used the mathematics of random walks to derive endpoint outcome distributions of the choices. This also furnished equivalent lotteries, presented in a purely economic, casino-like frame, in which starvation corresponded to winning nothing. Bayesian model comparison showed that--in both the foraging and the casino frames--participants' choices depended jointly on the probability of starvation and the expected endpoint value of the outcome, but could not be explained by economic models based on combinations of statistical moments or on rank-dependent utility. This implies that under precisely defined constraints biological principles are better suited to explain human decision-making than economic models based on endpoint utility maximization.

  18. Maintaining bone health in prostate cancer throughout the disease continuum.

    Science.gov (United States)

    Saad, Fred; Eastham, James

    2010-06-01

    Prostate cancer (PC) is the most prevalent malignancy in men, with 604,506 new cases diagnosed yearly worldwide. Maintaining bone health is important during all stages of PC, including patients who experience bone loss from androgen-deprivation therapy and patients who develop bone metastases. Patients with bone metastases often experience severe bone pain and are at increased risk for potentially debilitating skeletal-related events. Bisphosphonates are a well-established treatment option for patients with bone metastases from solid tumors and bone lesions from multiple myeloma. Zoledronic acid (ZOL) is the only bisphosphonate (BP) that has been extensively studied in patients with castration-recurrent PC and is indicated for treating patients with bone metastases from PC in conjunction with standard antineoplastic therapy. This review will examine the breadth of evidence supporting a role for ZOL and emerging therapies in managing patients with PC throughout the disease continuum. 2010 Elsevier Inc. All rights reserved.

  19. A taxonomy for human reliability analysis

    International Nuclear Information System (INIS)

    Beattie, J.D.; Iwasa-Madge, K.M.

    1984-01-01

    A human interaction taxonomy (classification scheme) was developed to facilitate human reliability analysis in a probabilistic safety evaluation of a nuclear power plant, being performed at Ontario Hydro. A human interaction occurs, by definition, when operators or maintainers manipulate, or respond to indication from, a plant component or system. The taxonomy aids the fault tree analyst by acting as a heuristic device. It helps define the range and type of human errors to be identified in the construction of fault trees, while keeping the identification by different analysts consistent. It decreases the workload associated with preliminary quantification of the large number of identified interactions by including a category called 'simple interactions'. Fault tree analysts quantify these according to a procedure developed by a team of human reliability specialists. The interactions which do not fit into this category are called 'complex' and are quantified by the human reliability team. The taxonomy is currently being used in fault tree construction in a probabilistic safety evaluation. As far as can be determined at this early stage, the potential benefits of consistency and completeness in identifying human interactions and streamlining the initial quantification are being realized

  20. Multinomial-exponential reliability function: a software reliability model

    International Nuclear Information System (INIS)

    Saiz de Bustamante, Amalio; Saiz de Bustamante, Barbara

    2003-01-01

    The multinomial-exponential reliability function (MERF) was developed during a detailed study of the software failure/correction processes. Later on MERF was approximated by a much simpler exponential reliability function (EARF), which keeps most of MERF mathematical properties, so the two functions together makes up a single reliability model. The reliability model MERF/EARF considers the software failure process as a non-homogeneous Poisson process (NHPP), and the repair (correction) process, a multinomial distribution. The model supposes that both processes are statistically independent. The paper discusses the model's theoretical basis, its mathematical properties and its application to software reliability. Nevertheless it is foreseen model applications to inspection and maintenance of physical systems. The paper includes a complete numerical example of the model application to a software reliability analysis