WorldWideScience

Sample records for reliability centered maintenance

  1. 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.

  2. 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

  3. Experience based reliability centered maintenance

    International Nuclear Information System (INIS)

    Haenninen, S.; Laakso, K.

    1993-03-01

    The systematic analysis and documentation of operating experiences should be included in a living NPP life management program. Failure mode and effects and maintenance effects analyses are suitable methods for analysis of the failure and corrective maintenance experiences of equipment. Combined use of the information on occurred functional failures and the decision tree logic of the reliability centered maintenance identifies applicable and effective preventive maintenance tasks of equipment in an old plant. In this study the electrical motor drives of closing and isolation valves (MOV) of TVO and Loviisa nuclear power plants were selected to serve as pilot study objects. The study was limited to valve drives having actuators manufactured by AUMA in Germany. The fault and maintenance history of MOVs from 1981 up to and including October 1991 in different safety and process systems at TVO 1 and 2 nuclear power units was at first analyzed in a systematic way. The scope of the components studied was 81 MOVs in safety-related systems and 127 other MOVs per each TVO unit. In the case of the Loviisa plant, the observation period was limited to three years, i.e. from February 1989 up to February 1992. The scope of the Loviisa 1 and 2 components studied was 44 respectively 95 MOVs. (25 refs., 22 figs., 8 tabs.)

  4. Demonstration of reliability centered maintenance

    International Nuclear Information System (INIS)

    Schwan, C.A.; Morgan, T.A.

    1991-04-01

    Reliability centered maintenance (RCM) is an approach to preventive maintenance planning and evaluation that has been used successfully by other industries, most notably the airlines and military. Now EPRI is demonstrating RCM in the commercial nuclear power industry. Just completed are large-scale, two-year demonstrations at Rochester Gas ampersand Electric (Ginna Nuclear Power Station) and Southern California Edison (San Onofre Nuclear Generating Station). Both demonstrations were begun in the spring of 1988. At each plant, RCM was performed on 12 to 21 major systems. Both demonstrations determined that RCM is an appropriate means to optimize a PM program and improve nuclear plant preventive maintenance on a large scale. Such favorable results had been suggested by three earlier EPRI pilot studies at Florida Power ampersand Light, Duke Power, and Southern California Edison. EPRI selected the Ginna and San Onofre sites because, together, they represent a broad range of utility and plant size, plant organization, plant age, and histories of availability and reliability. Significant steps in each demonstration included: selecting and prioritizing plant systems for RCM evaluation; performing the RCM evaluation steps on selected systems; evaluating the RCM recommendations by a multi-disciplinary task force; implementing the RCM recommendations; establishing a system to track and verify the RCM benefits; and establishing procedures to update the RCM bases and recommendations with time (a living program). 7 refs., 1 tab

  5. Program integration of predictive maintenance with reliability centered maintenance

    International Nuclear Information System (INIS)

    Strong, D.K. Jr; Wray, D.M.

    1990-01-01

    This paper addresses improving the safety and reliability of power plants in a cost-effective manner by integrating the recently developed reliability centered maintenance techniques with the traditional predictive maintenance techniques of nuclear power plants. The topics of the paper include a description of reliability centered maintenance (RCM), enhancing RCM with predictive maintenance, predictive maintenance programs, condition monitoring techniques, performance test techniques, the mid-Atlantic Reliability Centered Maintenance Users Group, test guides and the benefits of shared guide development

  6. 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.)

  7. 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.).

  8. Reliability centered maintenance streamlining through lessons learned

    International Nuclear Information System (INIS)

    Strong, D.K.

    1991-01-01

    In late 1986, PSE and G concluded that the Nuclear Department would develop a consistent approach to maintenance at Artificial Island (Salem and Hope Creak nuclear units). Preventive maintenance (PM) would be the heart of this approach. In the last six months of 1987 departments affected by the maintenance program participated on working groups that developed the Artificial Island maintenance philosophy. The central theme of the maintenance philosophy is the RCM (reliability centered maintenance) process. A pilot project tested the process in 1988. In 1989 the Central PM Group formed and in 1990 was given responsibility and authority to analyze, approve, implement, and control PM program changes. RCM is the central theme of the PM improvement effort but not the whole effort. Other important pieces included in this paper are: development of a common PM program, improvement of work instructions, development of predictive maintenance techniques into programs, development of a PM basis database, development of PM feedback from failure trends, root cause analysis, maintenance performance indicators, technicians, and engineers

  9. Reliability and risk treatment centered maintenance

    International Nuclear Information System (INIS)

    Pexa, Martin; Hladik, Tomas; Ales, Zdenek; Legat, Vaclav; Muller, Miroslav; Valasek, Petr; Havlu, Vit

    2014-01-01

    We propose a new methodology for application of well-known tools - RCM, RBI and SIF pro - with the aim to treat risks by means of suitable maintenance. The basis of the new methodology is the complex application of all three methods at the same time and not separately as is typical today. The proposed methodology suggests having just one managing team for reliability and risk treatment centred maintenance (RRTCM), employing existing RCM, RBI, and SIFpro tools concurrently. This approach allows for significant reduction of engineering activities' duration. In the proposed methodology these activities are staged into five phases and structured to eliminate all duplication resulting from separate application of the three tools. The newly proposed methodology saves 45% to 50% of the engineering workload and dequate significant financial savings.

  10. Reliability and risk treatment centered maintenance

    Energy Technology Data Exchange (ETDEWEB)

    Pexa, Martin; Hladik, Tomas; Ales, Zdenek; Legat, Vaclav; Muller, Miroslav; Valasek, Petr [Czech University of Life Sciences Prague, Kamycka (Czech Republic); Havlu, Vit [Unipetrol A. S, Prague (Czech Republic)

    2014-10-15

    We propose a new methodology for application of well-known tools - RCM, RBI and SIF pro - with the aim to treat risks by means of suitable maintenance. The basis of the new methodology is the complex application of all three methods at the same time and not separately as is typical today. The proposed methodology suggests having just one managing team for reliability and risk treatment centred maintenance (RRTCM), employing existing RCM, RBI, and SIFpro tools concurrently. This approach allows for significant reduction of engineering activities' duration. In the proposed methodology these activities are staged into five phases and structured to eliminate all duplication resulting from separate application of the three tools. The newly proposed methodology saves 45% to 50% of the engineering workload and dequate significant financial savings.

  11. Implementing a Reliability Centered Maintenance Program at NASA's Kennedy Space Center

    National Research Council Canada - National Science Library

    Tuttle, Raymond

    1998-01-01

    .... A reliability centered maintenance (RCM) program seeks to offer equal or greater reliability at decreased cost by insuring only applicable, effective maintenance is performed and by in large part replacing time based maintenance...

  12. Guide for generic application of Reliability Centered Maintenance (RCM) recommendations

    International Nuclear Information System (INIS)

    Schwan, C.A.; Toomey, G.E.; Morgan, T.A.; Darling, S.S.

    1991-02-01

    Previously completed reliability centered maintenance (RCM) studies form the basis for developing or refining a preventive maintenance program. This report describes a generic methodology that will help utilities optimize nuclear plant maintenance programs using RCM techniques. This guide addresses the following areas: history of the generic methodology development process, and use of the generic methodology for conducting system-to-system and component-to-component evaluations. 2 refs., 2 figs., 5 tabs

  13. A framework for reliability and risk centered maintenance

    International Nuclear Information System (INIS)

    Selvik, J.T.; Aven, T.

    2011-01-01

    Reliability centered maintenance (RCM) is a well-established analysis method for preventive maintenance planning. As its name indicates, reliability is the main point of reference for the planning, but consequences of failures are also assessed. However, uncertainties and risk are to a limited extent addressed by the RCM method, and in this paper we suggest an extension of the RCM to reliability and risk centered maintenance (RRCM) by also considering risk as the reference for the analysis in addition to reliability. A broad perspective on risk is adopted where uncertainties are the main component of risk in addition to possible events and associated consequences. A case from the offshore oil and gas industry is presented to illustrate and discuss the suggested approach.

  14. Comprehensive low-cost reliability centered maintenance. Final report

    International Nuclear Information System (INIS)

    Rotton, S.J.; Dozier, I.J.; Thow, R.

    1995-09-01

    Reliability Centered Maintenance (RCM) is a maintenance optimization approach that all electric utilities can apply to power plant systems. The Electric Power Research Institute and PECO Energy Company jointly sponsored this Comprehensive Low-Cost Reliability Centered Maintenance project to demonstrate that the standard RCM methodology could be streamlined to reduce the cost of analysis while maintaining a high quality product. EPRI's previous investigation of streamlined RCM methods being pioneered in the nuclear industry indicated that PECO Energy could expect to optimize its maintenance program at reduced cost by carefully controlling the scope without sacrificing documentation or technical quality. Using the insights obtained from these previous studies, three methods were defined in this project and were demonstrated in a large scale application to 60 systems at both the Limerick Generating Station and the Peach Bottom Atomic Power Station

  15. Reliability centered Maintenance (RCM) program for Chashma NPP (CHASNUPP)

    International Nuclear Information System (INIS)

    Khalid, S.; Khan, S.A.

    2000-01-01

    This paper describes the proposed Reliability Centered Maintenance (RCM) program for Chashma Nuclear Power Plant (CHASNUPP). Major steps are the identification of risk critical components and the implementation of RCM procedures. Identification of risk critical components is based upon the CHASNUPP level 1 PSA results (performed under IAEA TC Project PAK/9/019) which is near completion. The other requirements for implementation of RCM program is the qualitative analysis to be performed for identifying the dominant potential failure modes of each risk critical component and determination of the necessary maintenance activities, required to ensure reliable operation of the identified risk critical components. Implementation of RCM program for these components will lead to improvement in plant availability and safety together with reduction in the maintenance cost. Development - implementation of RCM program at this stage will help the CHASNUPP Maintenance department who is now developing the maintenance program - procedures for CHASNUPP. (author)

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

    International Nuclear Information System (INIS)

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

    1991-01-01

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

  17. Application of reliability centered maintenance to Embalse NPP

    International Nuclear Information System (INIS)

    Torres, Antonio; Perdomo, Manuel; Fornero, Damian; Corchera, Roberto

    2010-01-01

    One of the most recent applications of Probabilistic Safety Analysis to Embalse NPP is the Safety Oriented Maintenance Program developed through the Reliability Centered Maintenance (RCM) methodology. Such an application was carried out by a cooperated effort between the staff of nuclear safety department of NPP and experts from Instituto Superior de Tecnologias y Ciencias Aplicadas of Cuba. So far 6 technological systems have been analyzed with important results regarding the optimization of preventive and predictive maintenance program of those systems. Any tasks of RCM were automated via MOSEG code. The results of this study were focused on the elaboration and modification of the Preventive Program, prioritization of stocks, reorientation of predictive techniques and modification in the time parameters of maintenance. (author)

  18. Identification of tasks of maintenance centered in the reliability

    International Nuclear Information System (INIS)

    Torres V, A.; Rivero O, J.J.

    2004-01-01

    The methodology of Reliability Centered Maintenance (RCM) it has become, after the discovery of their advantages, an objective of many industrial facilities to optimize their maintenance. However, diverse subjective factors affect the determination of the parameters (technical of predictive to apply and times among interventions) that characterize the tasks of RCM. A method to determine the monitoring tasks at condition and the times more recommended for to apply the monitoring by time and the search of faults, with focus in system. This methodology has been computerized inside the code MOSEG Win Ver 1.0. The same has been applied with success to the determination of tasks of RCM in industrial objectives. (Author)

  19. Reliability centered maintenance : a case study of railway transit maintenance to achieve optimal performance.

    Science.gov (United States)

    2010-12-01

    The purpose of this qualitative case study was to identify the types of obstacles and patterns experienced by a single heavy rail transit agency located in North America that embedded a Reliability Centered Maintenance (RCM) Process. The outcome of t...

  20. 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

  1. PERENCANAAN PEMELIHARAAN MESIN BALLMILL DENGAN BASIS RCM (RELIABILITY CENTERED MAINTENANCE

    Directory of Open Access Journals (Sweden)

    Ahmad Kholid Alghofari

    2006-12-01

    Full Text Available Aktifitas produksi sering mengalami hambatan dikarenakan tidak berfungsinya mesin-mesin produksi yang dalam industri manufaktur merupakan komponen utama. Kegagalan beroperasi mesin mengakibatkan downtime yang ujung-ujungnya menurunkan produktifitas perusahaan. Oleh karenanya diperlukan sebuah sistem perencanaan pemeliharaan agar menghasilkan availability (ketersediaan mesin yang optimal. Perusahaan yang dijadikan proyek penelitian adalah PT. Sici Multi IndoMarmer yang merupakan perusahaan yang bergerak dalam bidang produksi keramik (kloset jongkok, kloset duduk, washtafel, tempat sabun dimana sistem pemeliharaan mesin, khususnya mesin ballmill yang telah dilakukan masih bersifat corrective maintenance. Tujuan dari penelitian ini adalah implementasi RCM (reliability centered maintenance untuk dapat menentukan pemeliharan yang optimal serta dapat memprediksikan langkah untuk mengatasi kerusakan yang mungkin terjadi pada periode berikutnya berdasarkan data-data yang ada. Dari pengolahan data dan analisa diperoleh komponen-komponen yang paling sering mengalami kerusakan pada mesin ballmill , penyebab kegagalan, keputusan seleksi dan rekomendasi yang dianjurkan untuk sistem pemeliharaan dengan basis RCM.

  2. Applying reliability centered maintenance analysis principles to inservice testing

    International Nuclear Information System (INIS)

    Flude, J.W.

    1994-01-01

    Federal regulations require nuclear power plants to use inservice test (IST) programs to ensure the operability of safety-related equipment. IST programs are based on American Society of Mechanical Engineers (ASME) Boiler and Pressure Vessel Code requirements. Many of these plants also use Reliability Centered Maintenance (RCM) to optimize system maintenance. ASME Code requirements are hard to change. The process for requesting authority to use an alternate strategy is long and expensive. The difficulties of obtaining this authority make the use of RCM method on safety-related systems not cost effective. An ASME research task force on Risk Based Inservice Testing is investigating changing the Code. The change will allow plants to apply RCM methods to the problem of maintenance strategy selection for safety-related systems. The research task force is working closely with the Codes and Standards sections to develop a process related to the RCM process. Some day plants will be able to use this process to develop more efficient and safer maintenance strategies

  3. RCM [reliability-centered maintenance] at Ginna: Preventive maintenance program optimization at year 20

    International Nuclear Information System (INIS)

    Edgar, E.C.

    1989-01-01

    The reliability-centered maintenance (RCM) program at Rochester Gas ampersand Electric Company's Ginna station is entering its second year. Of the 20 systems originally selected for evaluation, 10 are in various stages of completion, and recommendations resulting from the earliest systems studied are now being implemented. As expected, few major discoveries have been made in terms of preventive maintenance program failings or excesses. The performance of the now 20-yr-old plant has been excellent in recent years, and objectives focus more on ensuring continued high standards of safety, reliability, and economy than on maintenance program cost reduction

  4. Development of reliability centered maintenance methods and tools

    International Nuclear Information System (INIS)

    Jacquot, J.P.; Dubreuil-Chambardel, A.; Lannoy, A.; Monnier, B.

    1992-12-01

    This paper recalls the development of the RCM (Reliability Centered Maintenance) approach in the nuclear industry and describes the trial study implemented by EDF in the context of the OMF (RCM) Project. The approach developed is currently being applied to about thirty systems (Industrial Project). On a parallel, R and D efforts are being maintained to improve the selectivity of the analysis methods. These methods use Probabilistic Safety Study models, thereby guaranteeing better selectivity in the identification of safety critical elements and enhancing consistency between Maintenance and Safety studies. They also offer more detailed analysis of operation feedback, invoking for example Bayes' methods combining expert judgement and feedback data. Finally, they propose a functional and material representation of the plant. This dual representation describes both the functions assured by maintenance provisions and the material elements required for their implementation. In the final chapter, the targets of the future OMF workstation are summarized and the latter's insertion in the EDF information system is briefly described. (authors). 5 figs., 2 tabs., 7 refs

  5. A framework for intelligent reliability centered maintenance analysis

    International Nuclear Information System (INIS)

    Cheng Zhonghua; Jia Xisheng; Gao Ping; Wu Su; Wang Jianzhao

    2008-01-01

    To improve the efficiency of reliability-centered maintenance (RCM) analysis, case-based reasoning (CBR), as a kind of artificial intelligence (AI) technology, was successfully introduced into RCM analysis process, and a framework for intelligent RCM analysis (IRCMA) was studied. The idea for IRCMA is based on the fact that the historical records of RCM analysis on similar items can be referenced and used for the current RCM analysis of a new item. Because many common or similar items may exist in the analyzed equipment, the repeated tasks of RCM analysis can be considerably simplified or avoided by revising the similar cases in conducting RCM analysis. Based on the previous theory studies, an intelligent RCM analysis system (IRCMAS) prototype was developed. This research has focused on the description of the definition, basic principles as well as a framework of IRCMA, and discussion of critical techniques in the IRCMA. Finally, IRCMAS prototype is presented based on a case study

  6. Safety related maintenance in the framework of the reliability centered maintenance concept

    International Nuclear Information System (INIS)

    1992-07-01

    Elevated safety requirements and ever increasing costs of maintenance of nuclear power plants stimulate the interest in different methods and approaches to optimize maintenance activities. Among different concepts, the Reliability Centered Maintenance (RCM) as an approach to improve Preventive Maintenance (PM) programmes is being widely discussed an applied in several IAEA Member States. In order to summarize basic principles and current implementation of the RCM, the IAEA organized a Consultants Meeting in November 1990. The report prepared during that meeting was discussed during the Technical Committee Meeting (TCM) held in May 1991. Numerous technical presentations as well as panel and plenary discussions took place at the TCM. This document contains the report of the Consultants Meeting (modified to include comments of the TCM), a summary of the most important discussions as well as all 14 papers presented at the TCM

  7. A study of adopting maintenance rule under the periodic safety review and reliability centered maintenance program

    International Nuclear Information System (INIS)

    Kilyoo, Kim

    2001-01-01

    U.S Maintenance Rule (MR) has three main functions. One is to monitor the performance changes of SSCs (Structure, System, and Component) caused by risk informed applications. Periodic Safety Review (PSR) program is widely adopted in Europe while it is not adopted in U. S. A where MR and new oversight program are instead used. Recently, in Korea, it was determined to adopt PSR, and the first PSR program has started this year for Kori unit 1 as a pilot plant. Also, a traditional Reliability Centered Maintenance (RCM) has been performed for 4 systems of YGN unit 1 and 2 and it will be applied to the other nuclear power plants in Korea. However, since MR is adopting many useful concept of RCM, traditional RCM could not be further performed without being associated with MR. Thus, MR, RCM and PSR have recently become hot issue policies which should be well associated each other in Korea, and this paper suggests a desirable new maintenance process which would embrace the concepts of the three policies, and also discusses whether U.S. MR is necessary even though a PSR program is already adopted, and if necessary, then how cost-effectively it can be introduced to. (author)

  8. Optimization of reliability centered predictive maintenance scheme for inertial navigation system

    International Nuclear Information System (INIS)

    Jiang, Xiuhong; Duan, Fuhai; Tian, Heng; Wei, Xuedong

    2015-01-01

    The goal of this study is to propose a reliability centered predictive maintenance scheme for a complex structure Inertial Navigation System (INS) with several redundant components. GO Methodology is applied to build the INS reliability analysis model—GO chart. Components Remaining Useful Life (RUL) and system reliability are updated dynamically based on the combination of components lifetime distribution function, stress samples, and the system GO chart. Considering the redundant design in INS, maintenance time is based not only on components RUL, but also (and mainly) on the timing of when system reliability fails to meet the set threshold. The definition of components maintenance priority balances three factors: components importance to system, risk degree, and detection difficulty. Maintenance Priority Number (MPN) is introduced, which may provide quantitative maintenance priority results for all components. A maintenance unit time cost model is built based on components MPN, components RUL predictive model and maintenance intervals for the optimization of maintenance scope. The proposed scheme can be applied to serve as the reference for INS maintenance. Finally, three numerical examples prove the proposed predictive maintenance scheme is feasible and effective. - Highlights: • A dynamic PdM with a rolling horizon is proposed for INS with redundant components. • GO Methodology is applied to build the system reliability analysis model. • A concept of MPN is proposed to quantify the maintenance sequence of components. • An optimization model is built to select the optimal group of maintenance components. • The optimization goal is minimizing the cost of maintaining system reliability

  9. 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)

  10. Decreasing inventory of a cement factory roller mill parts using reliability centered maintenance method

    Science.gov (United States)

    Witantyo; Rindiyah, Anita

    2018-03-01

    According to data from maintenance planning and control, it was obtained that highest inventory value is non-routine components. Maintenance components are components which procured based on maintenance activities. The problem happens because there is no synchronization between maintenance activities and the components required. Reliability Centered Maintenance method is used to overcome the problem by reevaluating maintenance activities required components. The case chosen is roller mill system because it has the highest unscheduled downtime record. Components required for each maintenance activities will be determined by its failure distribution, so the number of components needed could be predicted. Moreover, those components will be reclassified from routine component to be non-routine component, so the procurement could be carried out regularly. Based on the conducted analysis, failure happens in almost every maintenance task are classified to become scheduled on condition task, scheduled discard task, schedule restoration task and no schedule maintenance. From 87 used components for maintenance activities are evaluated and there 19 components that experience reclassification from non-routine components to routine components. Then the reliability and need of those components were calculated for one-year operation period. Based on this invention, it is suggested to change all of the components in overhaul activity to increase the reliability of roller mill system. Besides, the inventory system should follow maintenance schedule and the number of required components in maintenance activity so the value of procurement will be decreased and the reliability system will increase.

  11. Optimization of Reliability Centered Maintenance Bassed on Maintenance Costs and Reliability with Consideration of Location of Components

    Directory of Open Access Journals (Sweden)

    Mahdi Karbasian

    2011-03-01

    Full Text Available The reliability of designing systems such as electrical and electronic circuits, power generation/ distribution networks and mechanical systems, in which the failure of a component may cause the whole system failure, and even the reliability of cellular manufacturing systems that their machines are connected to as series are critically important. So far approaches for improving the reliability of these systems have been mainly based on the enhancement of inherent reliability of any system component or increasing system reliability based on maintenance strategies. Also in some of the resources, only the influence of the location of systems' components on reliability is studied. Therefore, it seems other approaches have been rarely applied. In this paper, a multi criteria model has been proposed to perform a balance among a system's reliability, location costs, and its system maintenance. Finally, a numerical example has been presented and solved by the Lingo software.

  12. A reliability centered maintenance model applied to the auxiliary feedwater system of a nuclear power plant

    International Nuclear Information System (INIS)

    Araujo, Jefferson Borges

    1998-01-01

    The main objective of maintenance in a nuclear power plant is to assure that structures, systems and components will perform their design functions with reliability and availability in order to obtain a safety and economic electric power generation. Reliability Centered Maintenance (RCM) is a method of systematic review to develop or optimize Preventive Maintenance Programs. This study presents the objectives, concepts, organization and methods used in the development of RCM application to nuclear power plants. Some examples of this application are included, considering the Auxiliary Feedwater System of a generic two loops PWR nuclear power plant of Westinghouse design. (author)

  13. Hardware-oriented reliability centered maintenance for the diesel generators of Wolsong unit 1

    International Nuclear Information System (INIS)

    Bae, Sang Min; Park, Jin Hee; Kim, Tae Woon; Lee, Yoon Kee; Song, Jin Bae

    1997-01-01

    The DGs (Diesel Generators) in NPP (Nuclear Power Plant) has been used for the emergency electric power source to shut down the nuclear reactor safely in case of station blackout. The RCM (Reliability Centered Maintenance) has been applied to DGs for increasing the safety of NPP. The structured defects of DG were not remedied by the improvement of maintenance method. As the first stage of RCM, to find the structured defects, its failure modes were searched and analyzed through the ten year maintenance information. The structured defects such as the air compressor, the lubricating oil pressure, and the insufficient load were the root causes of main failures. The air reservoir reinstallation, the lubricating oil tube modification, the load bank installation, and the qualitative instrumentation were the solutions for the hardware oriented RCM of DGs. There remains the software oriented RCM such as the rejection of useless maintenance, the preventive maintenance, the database of maintenance information, and the predictive maintenance

  14. A Simulation Model for Machine Efficiency Improvement Using Reliability Centered Maintenance: Case Study of Semiconductor Factory

    Directory of Open Access Journals (Sweden)

    Srisawat Supsomboon

    2014-01-01

    Full Text Available The purpose of this study was to increase the quality of product by focusing on the machine efficiency improvement. The principle of the reliability centered maintenance (RCM was applied to increase the machine reliability. The objective was to create preventive maintenance plan under reliability centered maintenance method and to reduce defects. The study target was set to reduce the Lead PPM for a test machine by simulating the proposed preventive maintenance plan. The simulation optimization approach based on evolutionary algorithms was employed for the preventive maintenance technique selection process to select the PM interval that gave the best total cost and Lead PPM values. The research methodology includes procedures such as following the priority of critical components in test machine, analyzing the damage and risk level by using Failure Mode and Effects Analysis (FMEA, calculating the suitable replacement period through reliability estimation, and optimizing the preventive maintenance plan. From the result of the study it is shown that the Lead PPM of test machine can be reduced. The cost of preventive maintenance, cost of good product, and cost of lost product were decreased.

  15. The impact of reliability centered maintenance on plant prospects for license renewal

    International Nuclear Information System (INIS)

    Elliott, J.O.; Nakahara, Y.

    1991-01-01

    Much attention has been directed in recent years to means of extending nuclear power plant life. As many plants enter their third decade of service, the questions loom large of how to keep aging plants reliable, as well as how to assure reliability and safety to an extent sufficient to warrant license renewal at the end of the current licensing term. Concurrently the nuclear industry has seen a growing interest in reducing the cost and complexity of maintenance activities while at the same time improving plant reliability and availability. Attainment of these seemingly contradictory aims is being aided by the introduction of a maintenance philosophy developed originally by the airline industry and subsequently applied with great success both in that industry and the U.S. military services. Reliability Centered Maintenance (RCM), in its basic form, may be described as a consideration of reliability and maintenance problems from a systems level approach, allowing a focus on preservation of system functions as the aim of a maintenance program optimized for both safety and economics. It is this systematic view of plant maintenance, with the emphasis on preservation of overall functions rather than individual parts and components which sets RCM apart from past nuclear plant maintenance philosophies. It is also the factor which makes application of RCM an ideal first step in development of strategies for life extension and license renewal, both for aging plants, and for plants just beginning their first license term

  16. Reliability Centered Maintenance for Savannah River Site`s interim waste management facilities. Revision 1

    Energy Technology Data Exchange (ETDEWEB)

    Hauer, K.A. [Westinghouse Savannah River Co., Aiken, SC (United States); Wilson, J.F. [PRC, Inc. (US)

    1992-06-01

    The application of Reliability Centered Maintenance (RCM) has been shown to be an effective means to optimize maintenance programs or to establish new programs. The key to success of any RCM program is to customize the methodology to meet the specific needs of the implementing organization. This paper discusses how RCM is being used to establish the preventive maintenance program and how the resulting system data is being used to support the Technical Baseline reconstitution effort for the interim Waste Management Division of Westinghouse Savannah River Company (WSRC).

  17. Reliability Centered Maintenance for Savannah River Site's interim waste management facilities

    Energy Technology Data Exchange (ETDEWEB)

    Hauer, K.A. (Westinghouse Savannah River Co., Aiken, SC (United States)); Wilson, J.F. (PRC, Inc. (US))

    1992-01-01

    The application of Reliability Centered Maintenance (RCM) has been shown to be an effective means to optimize maintenance programs or to establish new programs. The key to success of any RCM program is to customize the methodology to meet the specific needs of the implementing organization. This paper discusses how RCM is being used to establish the preventive maintenance program and how the resulting system data is being used to support the Technical Baseline reconstitution effort for the interim Waste Management Division of Westinghouse Savannah River Company (WSRC).

  18. Reliability Centered Maintenance for Savannah River Site's interim waste management facilities

    International Nuclear Information System (INIS)

    Hauer, K.A.; Wilson, J.F.

    1992-01-01

    The application of Reliability Centered Maintenance (RCM) has been shown to be an effective means to optimize maintenance programs or to establish new programs. The key to success of any RCM program is to customize the methodology to meet the specific needs of the implementing organization. This paper discusses how RCM is being used to establish the preventive maintenance program and how the resulting system data is being used to support the Technical Baseline reconstitution effort for the interim Waste Management Division of Westinghouse Savannah River Company (WSRC)

  19. An evaluation of the Browns Ferry Nuclear Plant preventive maintenance program based on reliability centered maintenance analysis

    International Nuclear Information System (INIS)

    McCullough, C.L.; McCullough, C.A.

    1989-01-01

    Reliability centered maintenance (RCM) techniques were used to support a preventative maintenance (PM) upgrade program (PMUP) performed at TVA Browns Ferry Nuclear Plant (BFNP). The purpose of the RCM analysis was to identify critical equipment based on risk and economic importance and to evaluate the PM activities applicable to that equipment. The analysis may be conveniently divided into three steps, which will be outlined in the Approach section of this paper. The net benefit of the RCM approach was a prioritization of the focus of the PM upgrade program so that plant components receive attention proportional to their importance, and assurance that PM activities properly address the most likely component failure causes

  20. Quantified Risk Ranking Model for Condition-Based Risk and Reliability Centered Maintenance

    Science.gov (United States)

    Chattopadhyaya, Pradip Kumar; Basu, Sushil Kumar; Majumdar, Manik Chandra

    2017-06-01

    In the recent past, risk and reliability centered maintenance (RRCM) framework is introduced with a shift in the methodological focus from reliability and probabilities (expected values) to reliability, uncertainty and risk. In this paper authors explain a novel methodology for risk quantification and ranking the critical items for prioritizing the maintenance actions on the basis of condition-based risk and reliability centered maintenance (CBRRCM). The critical items are identified through criticality analysis of RPN values of items of a system and the maintenance significant precipitating factors (MSPF) of items are evaluated. The criticality of risk is assessed using three risk coefficients. The likelihood risk coefficient treats the probability as a fuzzy number. The abstract risk coefficient deduces risk influenced by uncertainty, sensitivity besides other factors. The third risk coefficient is called hazardous risk coefficient, which is due to anticipated hazards which may occur in the future and the risk is deduced from criteria of consequences on safety, environment, maintenance and economic risks with corresponding cost for consequences. The characteristic values of all the three risk coefficients are obtained with a particular test. With few more tests on the system, the values may change significantly within controlling range of each coefficient, hence `random number simulation' is resorted to obtain one distinctive value for each coefficient. The risk coefficients are statistically added to obtain final risk coefficient of each critical item and then the final rankings of critical items are estimated. The prioritization in ranking of critical items using the developed mathematical model for risk assessment shall be useful in optimization of financial losses and timing of maintenance actions.

  1. The engine maintenance scheduling by using reliability centered maintenance method and the identification of 5S application in PT. XYZ

    Science.gov (United States)

    Sembiring, N.; Panjaitan, N.; Saragih, A. F.

    2018-02-01

    PT. XYZ is a manufacturing company that produces fresh fruit bunches (FFB) to Crude Palm Oil (CPO) and Palm Kernel Oil (PKO). PT. XYZ consists of six work stations: receipt station, sterilizing station, thressing station, pressing station, clarification station, and kernelery station. So far, the company is still implementing corrective maintenance maintenance system for production machines where the machine repair is done after damage occurs. Problems at PT. XYZ is the absence of scheduling engine maintenance in a planned manner resulting in the engine often damaged which can disrupt the smooth production. Another factor that is the problem in this research is the kernel station environment that becomes less convenient for operators such as there are machines and equipment not used in the production area, slippery, muddy, scattered fibers, incomplete use of PPE, and lack of employee discipline. The most commonly damaged machine is in the seed processing station (kernel station) which is cake breaker conveyor machine. The solution of this problem is to propose a schedule plan for maintenance of the machine by using the method of reliability centered maintenance and also the application of 5S. The result of the application of Reliability Centered maintenance method is obtained four components that must be treated scheduled (time directed), namely: for bearing component is 37 days, gearbox component is 97 days, CBC pen component is 35 days and conveyor pedal component is 32 days While after identification the application of 5S obtained the proposed corporate environmental improvement measures in accordance with the principles of 5S where unused goods will be moved from the production area, grouping goods based on their use, determining the procedure of cleaning the production area, conducting inspection in the use of PPE, and making 5S slogans.

  2. Reliability centered maintenance as an optimization tool for electrical power plants

    International Nuclear Information System (INIS)

    Jacquot, J.P.; Bryla, P.; Martin-Mattei, C.; Meuwisse, C.

    1997-08-01

    Seven years ago, Electricite de France launched a Reliability Centered Maintenance (RCM) pilot project to optimize preventive maintenance for its nuclear power plants. After a feasibility study, a RCM method was standardized. It is now applied on a large scale to the 50 EDF nuclear units. A RCM workstation based on this standardized method has been developed and is now used in each plant. In the next step, it is considered whether a Risk based Approach can be included in this RCM process in order to analyze critical passive components such as pipes and supports. Considering the potential advantages of these optimization techniques, a dedicated process has been also developed for maintenance of future plants, gas turbines, or nuclear units. A survey of these different developments of methods and tools is presented. (author)

  3. Status of the reliability centered maintenance program at Ontario Hydro's Bruce 'A' Nuclear Division

    International Nuclear Information System (INIS)

    Khan, I.

    1995-01-01

    Bruce A started a preventive maintenance (PM) quality improvement program in August of 1991. This initiative was taken to address the concerns expressed by the AECB and the Peer Audits finding. The concerns were on the quality of the Bruce A PM Program and its execution in the field. Reliability Centered Maintenance (RCM) analysis was selected as the PM program quality improvement and optimization technique. Therefore, RCM became a key component of Bruce A's Integrated PM program and maintenance strategy. As a result of RCM implementation, and improvements in the work planning and scheduling process, Bruce A is seeing downward trends in the corrective maintenance work load, maintenance preventable forced outages, overdue/missed PM tasks and corrective maintenance backlog. Control Room Operators have reported observing an improvement in systems and equipment response to transients. Other benefits include a documented, controlled and traceable PM program. In addition, the team approach required by RCM has started to improve staff confidence in the PM program which, in turn, is improving the compliance with the PM program. (author)

  4. Reliability centered maintenance pilot system implementation 241-AP-tank farm primary ventilation system final report

    International Nuclear Information System (INIS)

    MOORE TL

    2001-01-01

    When the Hanford Site Tank Farms' mission was safe storage of radioactive waste in underground storage tanks, maintenance activities focused on time-based preventive maintenance. Tank Farms' new mission to deliver waste to a vitrification plant where the waste will be processed into a form suitable for permanent storage requires a more efficient and proactive approach to maintenance. Systems must be maintained to ensure that they are operational and available to support waste feed delivery on schedule with a minimum of unplanned outages. This report describes the Reliability Centered Maintenance (RCM) pilot system that was implemented in the 241-AP Tank Farm Primary Ventilation System under PI-ORP-009 of the contract between the U.S. Department of Energy, Office of River Protection and CH2M HILL Hanford Group Inc. (CHG). The RCM analytical techniques focus on monitoring the condition of operating systems to predict equipment failures so that maintenance activities can be completed in time to prevent or mitigate unplanned equipment outages. This approach allows maintenance activities to be managed with minimal impact on plant operations. The pilot demonstration provided an opportunity for CHG staff-training in RCM principles and tailoring of the RCM approach to the Hanford Tank Farms' unique needs. This report details the implementation of RCM on a pilot system in Tank Farms

  5. Reliability-centered maintenance for ground-based large optical telescopes and radio antenna arrays

    Science.gov (United States)

    Marchiori, G.; Formentin, F.; Rampini, F.

    2014-07-01

    In the last years, EIE GROUP has been more and more involved in large optical telescopes and radio antennas array projects. In this frame, the paper describes a fundamental aspect of the Logistic Support Analysis (LSA) process, that is the application of the Reliability-Centered Maintenance (RCM) methodology for the generation of maintenance plans for ground-based large optical telescopes and radio antennas arrays. This helps maintenance engineers to make sure that the telescopes continue to work properly, doing what their users require them to do in their present operating conditions. The main objective of the RCM process is to establish the complete maintenance regime, with the safe minimum required maintenance, carried out without any risk to personnel, telescope and subsystems. At the same time, a correct application of the RCM allows to increase the cost effectiveness, telescope uptime and items availability, and to provide greater understanding of the level of risk that the organization is managing. At the same time, engineers shall make a great effort since the initial phase of the project to obtain a telescope requiring easy maintenance activities and simple replacement of the major assemblies, taking special care on the accesses design and items location, implementation and design of special lifting equipment and handling devices for the heavy items. This maintenance engineering framework is based on seven points, which lead to the main steps of the RCM program. The initial steps of the RCM process consist of: system selection and data collection (MTBF, MTTR, etc.), definition of system boundaries and operating context, telescope description with the use of functional block diagrams, and the running of a FMECA to address the dominant causes of equipment failure and to lay down the Critical Items List. In the second part of the process the RCM logic is applied, which helps to determine the appropriate maintenance tasks for each identified failure mode. Once

  6. Large-scale demonstration of reliability centered maintenance at two nuclear generating stations

    International Nuclear Information System (INIS)

    Gaertner, J.P.; Edgar, C.; Rodin, M.E.

    1989-01-01

    This paper reports that after successful single-system pilot applications of Reliability Centered Maintenance (RCM) at various utilities, EPRI with Rochester Gas and Electric and Southern California Edison is undertaking multiple-system applications of RCM at their respective nuclear plants. The objective is to demonstrate the feasibility and cost-effectiveness of large-scale RCM application. In addition, each utility has plant-specific objectives to improve maintenance and plant availability. Each project has selected a prioritized list of some 15-20 systems on which to perform RCM. Each project is employing somewhat different RCM analysis methods, both of which conform to a global RCM definition applicable to all EPRI RCM work to date. Each project has developed important insights for improving cost and value of future analyses. Both projects will have applied the RCM process, including implementation, on several plant systems by April 1989

  7. Guide for monitoring effectiveness of utility Reliability Centered Maintenance (RCM) programs

    International Nuclear Information System (INIS)

    Midgett, W.D.; Wilson, J.F.; Krochmal, D.F.; Owsenek, L.W.

    1991-02-01

    Reliability centered maintenance (RCM) programs help utilities optimize preventive maintenance efforts while improving plant safety and economy through increased dependability of plant components. The project team developed this guide and accompanying methodology based on status updates from the Ginna and San Onofre demonstration projects. These updates addressed areas ranging from system selection to the effectiveness of RCM program implementation. In addition, the team incorporated information from a 12-utility survey soliciting opinions on the need for a methodology to monitor RCM cost-effectiveness. An analysis of the 12-utility survey showed that no techniques had been developed to measure RCM program cost-effectiveness. Thus, this guide addresses two key areas: Pros and cons of various monitoring techniques available to assess the overall effectiveness of RCM and a methodology for specifically evaluating the cost-effectiveness of RCM programs. 1 fig

  8. ANALISIS MODA KEGAGALAN DENGAN PENDEKATAN RELIABILITY CENTERED MAINTENANCE (RCM (Studi kasus Baking Section Mesin Imfori PT Nissin Biskuit Indonesia

    Directory of Open Access Journals (Sweden)

    Sri Hartini

    2012-02-01

    Full Text Available Reliability Centered Maintenance (RCM adalah suatu pendekatan perawatan yang berbasis pada upaya menjamin keandalan mesin. Dengan pendekatan ini, perawatan ditujukan untuk menjamin agar asset terus menerus mencapai kemampuan dasarnya. Dalam penelitian dilakukan analisis fungsi sistem yang tepat terhadap Baking Section mesin Imaforni PT Nissin Biskuit Indonesia melalui pendekatan RCM untuk mengetahui moda kegagalan yang dapat menyebabkan sistem kehilangan fungsinya. Kata Kunci : Fungsi Sistem,Moda Kegagalan,Reliability Centered Maintenance.

  9. Failure analysis – basic step of applying Reliability Centered Maintenance in general aviation

    Directory of Open Access Journals (Sweden)

    Martin BUGAJ

    2012-01-01

    Full Text Available Performing a reliability analysis on a product or system can actually include a number of different analyses to determine how reliable the product or system is. A reliability centered maintenance program consists of a set of scheduled tasks generated on the basis of specific reliability characteristics of the equipment they are designed to protect. Complex equipment is composed of a vast number of parts and assemblies. All these items can be expected to fail at one time or another, but some of the failures have more serious consequences than others. Certain kinds of failures have a direct effect on operating safety, and others affect the operational capability of the equipment. The consequences of a particular failure depend on the design of the item and the equipment in which it is installed. Although the environment in which the equipment is operated is sometimes an additional factor, the impact of failures on the equipment, and hence their consequences for the operating organization, are established primarily by the equipment designer. Failure consequences are therefore a primary inherent reliability characteristic.

  10. 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.

  11. Application of reliability centered maintenance for nuclear power station in Japan

    International Nuclear Information System (INIS)

    Kumano, Haruyuki; Honda, Hironobu.

    1990-01-01

    The reliability centered maintenance (RCM) method has been widely used with good results in aviation companies in the U.S. to ensure positive preventive maintenance and management. In addition, the Electric Power Research Institute has been making studies and tests in an effort to apply the RCM method to nuclear power plants. The present report shows and discusses some results of a preliminary study aimed at the introduction of the RCM method to nuclear power plants in Japan. The history of the development and application of RCM is outlined first, and the procedure of its implementation is then described and discussed. The procedure consists of five major steps: collection of data, identification of system components, analysis of the functions of the system, selection of required tasks for preventive management, and packaging. Some actual examples of the application of RCM to nuclear power plants in the U.S. are described. And finally, the report discusses some major problems to be solved to permit the application of RCM to nuclear power plants in Japan. (N.K.)

  12. Reliability Centered Maintenance (RCM) Methodology and Application to the Shutdown Cooling System for APR-1400 Reactors

    Energy Technology Data Exchange (ETDEWEB)

    Faragalla, Mohamed M.; Emmanuel, Efenji; Alhammadi, Ibrahim; Awwal, Arigi M.; Lee, Yong Kwan [KEPCO International Nuclear Graduate School, Ulsan (Korea, Republic of)

    2016-10-15

    Shutdown Cooling System (SCS) is a safety-related system that is used in conjunction with the Main Steam and Main or Auxiliary Feedwater Systems to reduce the temperature of the Reactor Coolant System (RCS) in post shutdown periods from the hot shutdown operating temperature to the refueling temperature. In this paper RCM methodology is applied to (SCS). RCM analysis is performed based on evaluation of Failure Modes Effects and Criticality Analysis (FME and CA) on the component, system and plant. The Logic Tree Analysis (LTA) is used to determine the optimum maintenance tasks. The main objectives of RCM is the safety, preserve the System function, the cost-effective maintenance of the plant components and increase the reliability and availability value. The RCM methodology is useful for improving the equipment reliability by strengthening the management of equipment condition, and leads to a significant decrease in the number of periodical maintenance, extended maintenance cycle, longer useful life of equipment, and decrease in overall maintenance cost. It also focuses on the safety of the system by assigning criticality index to the various components and further selecting maintenance activities based on the risk of failure involved. Therefore, it can be said that RCM introduces a maintenance plan designed for maximum safety in an economical manner and making the system more reliable. For the SCP, increasing the number of condition monitoring tasks will improve the availability of the SCP. It is recommended to reduce the number of periodic maintenance activities.

  13. Identification of tasks of maintenance centered in the reliability; Identificacion de tareas de mantenimiento centrado en la confiabilidad

    Energy Technology Data Exchange (ETDEWEB)

    Torres V, A.; Rivero O, J.J. [Dpto. Ingenieria Nuclear, Instituto Superior de Tecnologias y Ciencias Aplicadas, Ave. Salvador Allende y Luaces, Quinta de los Molinos, Plaza, Ciudad Habana (Cuba)]. e-mail: atorres@fctn.isctn.edu.cu

    2004-07-01

    The methodology of Reliability Centered Maintenance (RCM) it has become, after the discovery of their advantages, an objective of many industrial facilities to optimize their maintenance. However, diverse subjective factors affect the determination of the parameters (technical of predictive to apply and times among interventions) that characterize the tasks of RCM. A method to determine the monitoring tasks at condition and the times more recommended for to apply the monitoring by time and the search of faults, with focus in system. This methodology has been computerized inside the code MOSEG Win Ver 1.0. The same has been applied with success to the determination of tasks of RCM in industrial objectives. (Author)

  14. A New Biobjective Model to Optimize Integrated Redundancy Allocation and Reliability-Centered Maintenance Problems in a System Using Metaheuristics

    Directory of Open Access Journals (Sweden)

    Shima MohammadZadeh Dogahe

    2015-01-01

    Full Text Available A novel integrated model is proposed to optimize the redundancy allocation problem (RAP and the reliability-centered maintenance (RCM simultaneously. A system of both repairable and nonrepairable components has been considered. In this system, electronic components are nonrepairable while mechanical components are mostly repairable. For nonrepairable components, a redundancy allocation problem is dealt with to determine optimal redundancy strategy and number of redundant components to be implemented in each subsystem. In addition, a maintenance scheduling problem is considered for repairable components in order to identify the best maintenance policy and optimize system reliability. Both active and cold standby redundancy strategies have been taken into account for electronic components. Also, net present value of the secondary cost including operational and maintenance costs has been calculated. The problem is formulated as a biobjective mathematical programming model aiming to reach a tradeoff between system reliability and cost. Three metaheuristic algorithms are employed to solve the proposed model: Nondominated Sorting Genetic Algorithm (NSGA-II, Multiobjective Particle Swarm Optimization (MOPSO, and Multiobjective Firefly Algorithm (MOFA. Several test problems are solved using the mentioned algorithms to test efficiency and effectiveness of the solution approaches and obtained results are analyzed.

  15. Perancangan Sistem Pemeliharaan Menggunakan Metode Reliability Centered Maintenance (RCM Pada Pulverizer (Studi Kasus: PLTU Paiton Unit 3

    Directory of Open Access Journals (Sweden)

    RATNA BHAKTI PUSPITA SARI

    2017-03-01

    Full Text Available PLTU Paiton Unit 3 merupakan perusahaan yang bergerak di bidang produksi listrik menggunakan bahan baku batubara yang terletak di Paiton, Probolinggo. Untuk mencapai target, proses produksi dilakukan 24 jam selama 1 tahun tanpa henti. Program pemeliharaan mesin sangat penting untuk kelancaran proses produksi. Dalam rangka mencapai target tersebut dituntut adanya kelancaran batubara dari silo hingga surface burner menggunakan pulverizer. Data dari Departemen Engineering menunjukkan bahwa beberapa subsistem pulverizer sering mengalami kerusakan yang dapat menimbulkan kegagalan pada sistem tersebut. Penelitian tugas akhir ini menggunakan metode Reliability Centered Maintenance (RCM untuk menurunkan tingkat breakdown mesin dan downtime produksi. Data historis kerusakan pulverizer dianalisa. Kemudian kegagalan dari suatu komponen yang dapat menyebabkan kegagalan fungsi dari sistem diidentifikasi menggunakan metode Failure Mode and Effect Analysis (FMEA. Selanjutnya menggunakan RCM Decision Worksheet untuk mengetahui bagian dari sistem yang gagal dan perlu dilakukan tindakan perbaikan dan pencegahan berdasarkan kegagalan yang ada agar kejadian yang sama tidak terulang dan menentukan kegiatan perancang perawatan yang tepat pada setiap komponen Berdasarkan analisis data secara Reliability Centered Maintenance (RCM terdapat 12 failure mode yang terjadi pada pulverizer. 3 failure mode dapat dicegah dengan scheduled restoration task, 8 failure mode dapat dicegah dengan scheduled discard task, dan 1 failure mode dapat dicegah dengan redesign. Analisis kuantitatif menggunakan distribusi kegagalan dengan perangkat lunak Weibull++6 didapatkan MTBF grinding roller 2880,66 jam, MTBF hydraulic pump 5075,06 jam, MTBF gearbox 5381,65 jam dan MTBF coal feeder 525,17 jam.

  16. Application of reliability-centered maintenance to boiling water reactor emergency core cooling systems fault-tree analysis

    International Nuclear Information System (INIS)

    Choi, Y.A.; Feltus, M.A.

    1995-01-01

    Reliability-centered maintenance (RCM) methods are applied to boiling water reactor plant-specific emergency core cooling system probabilistic risk assessment (PRA) fault trees. The RCM is a technique that is system function-based, for improving a preventive maintenance (PM) program, which is applied on a component basis. Many PM programs are based on time-directed maintenance tasks, while RCM methods focus on component condition-directed maintenance tasks. Stroke time test data for motor-operated valves (MOVs) are used to address three aspects concerning RCM: (a) to determine if MOV stroke time testing was useful as a condition-directed PM task; (b) to determine and compare the plant-specific MOV failure data from a broad RCM philosophy time period compared with a PM period and, also, compared with generic industry MOV failure data; and (c) to determine the effects and impact of the plant-specific MOV failure data on core damage frequency (CDF) and system unavailabilities for these emergency systems. The MOV stroke time test data from four emergency core cooling systems [i.e., high-pressure coolant injection (HPCI), reactor core isolation cooling (RCIC), low-pressure core spray (LPCS), and residual heat removal/low-pressure coolant injection (RHR/LPCI)] were gathered from Philadelphia Electric Company's Peach Bottom Atomic Power Station Units 2 and 3 between 1980 and 1992. The analyses showed that MOV stroke time testing was not a predictor for eminent failure and should be considered as a go/no-go test. The failure data from the broad RCM philosophy showed an improvement compared with the PM-period failure rates in the emergency core cooling system MOVs. Also, the plant-specific MOV failure rates for both maintenance philosophies were shown to be lower than the generic industry estimates

  17. Reliability-Centered Maintenance

    Science.gov (United States)

    1978-12-29

    and Eisenhart et al. (1947) summarized other statistical developments derived at Columbia. The second period of development, which had its roots in...January 1970 (FFA 120). Eisenhart , C., M. W. I-lastay, and W. A. Wallis (1947) Techniques of Statistical Analysis. McGraw-Hill Book Company, Inc., New...Miller, Douglas R. (1976) Abnost Sure Comiparisons ol Renewal Processes and Poisso:i Processes u’to *; Application to Reliabilityj Theo ; t, University of

  18. A reliability centered maintenance model applied to the auxiliary feedwater system of a nuclear power plant; Um modelo de manutencao centrada em confiabilidade aplicada ao sistema de agua de alimentacaco auxiliar de uma usina nuclear

    Energy Technology Data Exchange (ETDEWEB)

    Araujo, Jefferson Borges

    1998-01-15

    The main objective of maintenance in a nuclear power plant is to assure that structures, systems and components will perform their design functions with reliability and availability in order to obtain a safety and economic electric power generation. Reliability Centered Maintenance (RCM) is a method of systematic review to develop or optimize Preventive Maintenance Programs. This study presents the objectives, concepts, organization and methods used in the development of RCM application to nuclear power plants. Some examples of this application are included, considering the Auxiliary Feedwater System of a generic two loops PWR nuclear power plant of Westinghouse design. (author)

  19. Reliability centered maintenance applied to gas turbines, a deeper methodological study; Optimisation de la maintenance par la fiabilite appliquee aux turbines a combustion: approfondissement methodologique

    Energy Technology Data Exchange (ETDEWEB)

    Despujols, A; Delbos, J P; Zuliani, G

    1996-12-31

    The 9000E`combustion turbine study is unique in that it applied he RCM procedure to a power station before construction had begun on it. This has resulted in a maintenance programme being determined from the outset, rather than an existing programme being improved. The analysis begins with a search of the functions required by the unit, its operating states and its failure modes, then moves on to look at different systems to establish functional trees followed by failure trees. The lowest leaves on these graphs correspond respectively to functions carried out by important equipment nd their failure modes. Following on from this hierarchical procedure, each of the items of equipment are studies in an analysis of the failures modes, their effects and their criticality. The absence of feedback on this machine, the lack of data on the technology and the small size of the equipment (by comparison with those encountered in a nuclear unit), all contribute to limiting the level of decomposition. Tables are thus obtained which show the failure modes of an item of equipment, their origin, their effects on a system and unit level, the potential damage they cause, their severity, expert estimates of the frequency with they are likely to appear, their criticality and their evidence. The next step is a crucial one since it produces the results expected from the previous stages. It relies on task selection logic which has been honed to better take account of the obvious or hidden character of the failures. Not only must preventive operations to stop critical failure modes from occurring be suggested, but certain operations must be prescribed in order for breakdowns to be revealed. In practice, the state of the redundant or protective equipment has to be known when some of their failure modes remain hidden from the operator. The risk of a double failure with serious consequences becomes a probability when their breakdown state is not detected. (authors) 15 refs.

  20. Reliability centered maintenance applied to gas turbines, a deeper methodological study; Optimisation de la maintenance par la fiabilite appliquee aux turbines a combustion: approfondissement methodologique

    Energy Technology Data Exchange (ETDEWEB)

    Despujols, A.; Delbos, J.P.; Zuliani, G.

    1995-12-31

    The 9000E`combustion turbine study is unique in that it applied he RCM procedure to a power station before construction had begun on it. This has resulted in a maintenance programme being determined from the outset, rather than an existing programme being improved. The analysis begins with a search of the functions required by the unit, its operating states and its failure modes, then moves on to look at different systems to establish functional trees followed by failure trees. The lowest leaves on these graphs correspond respectively to functions carried out by important equipment nd their failure modes. Following on from this hierarchical procedure, each of the items of equipment are studies in an analysis of the failures modes, their effects and their criticality. The absence of feedback on this machine, the lack of data on the technology and the small size of the equipment (by comparison with those encountered in a nuclear unit), all contribute to limiting the level of decomposition. Tables are thus obtained which show the failure modes of an item of equipment, their origin, their effects on a system and unit level, the potential damage they cause, their severity, expert estimates of the frequency with they are likely to appear, their criticality and their evidence. The next step is a crucial one since it produces the results expected from the previous stages. It relies on task selection logic which has been honed to better take account of the obvious or hidden character of the failures. Not only must preventive operations to stop critical failure modes from occurring be suggested, but certain operations must be prescribed in order for breakdowns to be revealed. In practice, the state of the redundant or protective equipment has to be known when some of their failure modes remain hidden from the operator. The risk of a double failure with serious consequences becomes a probability when their breakdown state is not detected. (authors) 15 refs.

  1. 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

  2. Perencanaan Kegiatan Maintenance Dengan Metode Reability Centered Maintenance (Rcm) II

    OpenAIRE

    Rachmad Hidayat; Nachnul Ansori; Ali Imron

    2010-01-01

    Maintenance Activity Planning by Reability Centered Maintenance (RCM) II Method. This research discussmaintenance activity by using RCM II method to determine failure function risk at compresor screw. Calculation isgiven to magnitude optimum time maintenance interval by considering the cost maintenance and the cost reparation.From the research results with RPN points out that critical component that needs to get main priority in givemaintenance on compresor screw are bust logistic on timeworn...

  3. Reliability theory with applications to preventive maintenance

    CERN Document Server

    Gertsbakh, Ilya

    2000-01-01

    The material in this book was first presented as a one-semester course in Relia­ bility Theory and Preventive Maintenance for M.Sc. students of the Industrial Engineering Department of Ben Gurion University in the 1997/98 and 1998/99 academic years. Engineering students are mainly interested in the applied part of this theory. The value of preventive maintenance theory lies in the possibility of its imple­ mentation, which crucially depends on how we handle statistical reliability data. The very nature of the object of reliability theory - system lifetime - makes it extremely difficult to collect large amounts of data. The data available are usu­ ally incomplete, e.g. heavily censored. Thus, the desire to make the course material more applicable led me to include in the course topics such as mod­ eling system lifetime distributions (Chaps. 1,2) and the maximum likelihood techniques for lifetime data processing (Chap. 3). A course in the theory of statistics is aprerequisite for these lectures. Stan­ dard...

  4. 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...

  5. Exact reliability quantification of highly reliable systems with maintenance

    Energy Technology Data Exchange (ETDEWEB)

    Bris, Radim, E-mail: radim.bris@vsb.c [VSB-Technical University Ostrava, Faculty of Electrical Engineering and Computer Science, Department of Applied Mathematics, 17. listopadu 15, 70833 Ostrava-Poruba (Czech Republic)

    2010-12-15

    When a system is composed of highly reliable elements, exact reliability quantification may be problematic, because computer accuracy is limited. Inaccuracy can be due to different aspects. For example, an error may be made when subtracting two numbers that are very close to each other, or at the process of summation of many very different numbers, etc. The basic objective of this paper is to find a procedure, which eliminates errors made by PC when calculations close to an error limit are executed. Highly reliable system is represented by the use of directed acyclic graph which is composed from terminal nodes, i.e. highly reliable input elements, internal nodes representing subsystems and edges that bind all of these nodes. Three admissible unavailability models of terminal nodes are introduced, including both corrective and preventive maintenance. The algorithm for exact unavailability calculation of terminal nodes is based on merits of a high-performance language for technical computing MATLAB. System unavailability quantification procedure applied to a graph structure, which considers both independent and dependent (i.e. repeatedly occurring) terminal nodes is based on combinatorial principle. This principle requires summation of a lot of very different non-negative numbers, which may be a source of an inaccuracy. That is why another algorithm for exact summation of such numbers is designed in the paper. The summation procedure uses benefits from a special number system with the base represented by the value 2{sup 32}. Computational efficiency of the new computing methodology is compared with advanced simulation software. Various calculations on systems from references are performed to emphasize merits of the methodology.

  6. 78 FR 44475 - Protection System Maintenance Reliability Standard

    Science.gov (United States)

    2013-07-24

    ... that the performance or product has some reliability-related value, then the requirement will have...] Protection System Maintenance Reliability Standard AGENCY: Federal Energy Regulatory Commission, Energy... Commission proposes to approve a revised Reliability Standard, PRC-005- 2--Protection System Maintenance, to...

  7. Present status of the Nuclear Maintenance Training Center

    International Nuclear Information System (INIS)

    Kotani, Fumio

    1995-01-01

    The education and training to keep and improve the knowledge and skills of the maintenance personnel and to hand down the skills undoubtedly play important roles in safe operation and increased reliability to a nuclear power station. The Nuclear Maintenance Training Center (hereafter called the Center) provides a variety of education and training curriculums based on the levels and abilities of the trainees. The Center aims to enhance the personnel's maintenance technique by offering the curriculums on maintenance basic education for operators and supporting education and training for the personnel of contractors. The Center has two main features: first, it has the actual components or the equipment similar to the actual components which will enable the practical training; second, we regard the past troubles as valuable experiences and, therefore, focuses on the education to prevent recurrence of troubles by teaching the trainees the meaning and necessity of the training they take. For eleven years since the establishment of the Center, it has been utilized by the total number of about 60,000 people. As for the tasks in the future, the Center is expected to vitalize itself to give attractive education and training and become more actively involved in development of the maintenance personnel with the adequate knowledge and skills. (author)

  8. Reliability centred maintenance of nuclear power plant facilities

    International Nuclear Information System (INIS)

    Kovacs, Zoltan; Novakova, Helena; Hlavac, Pavol; Janicek, Frantisek

    2011-01-01

    A method for the optimization of preventive maintenance nuclear power plant equipment, i.e. reliability centred maintenance, is described. The method enables procedures and procedure schedules to be defined such as allow the maintenance cost to be minimized without compromising operational safety or reliability. Also, combinations of facilities which remain available and ensure reliable operation of the reactor unit during the maintenance of other pieces of equipment are identified. The condition-based maintenance concept is used in this process, thereby preventing unnecessary operator interventions into the equipment, which are often associated with human errors. Where probabilistic safety assessment is available, the most important structures, systems and components with the highest maintenance priority can be identified. (orig.)

  9. Integrated reliability condition monitoring and maintenance of equipment

    CERN Document Server

    Osarenren, John

    2015-01-01

    Consider a Viable and Cost-Effective Platform for the Industries of the Future (IOF) Benefit from improved safety, performance, and product deliveries to your customers. Achieve a higher rate of equipment availability, performance, product quality, and reliability. Integrated Reliability: Condition Monitoring and Maintenance of Equipment incorporates reliable engineering and mathematical modeling to help you move toward sustainable development in reliability condition monitoring and maintenance. This text introduces a cost-effective integrated reliability growth monitor, integrated reliability degradation monitor, technological inheritance coefficient sensors, and a maintenance tool that supplies real-time information for predicting and preventing potential failures of manufacturing processes and equipment. The author highlights five key elements that are essential to any improvement program: improving overall equipment and part effectiveness, quality, and reliability; improving process performance with maint...

  10. Technical information report: Plasma melter operation, reliability, and maintenance analysis

    International Nuclear Information System (INIS)

    Hendrickson, D.W.

    1995-01-01

    This document provides a technical report of operability, reliability, and maintenance of a plasma melter for low-level waste vitrification, in support of the Hanford Tank Waste Remediation System (TWRS) Low-Level Waste (LLW) Vitrification Program. A process description is provided that minimizes maintenance and downtime and includes material and energy balances, equipment sizes and arrangement, startup/operation/maintence/shutdown cycle descriptions, and basis for scale-up to a 200 metric ton/day production facility. Operational requirements are provided including utilities, feeds, labor, and maintenance. Equipment reliability estimates and maintenance requirements are provided which includes a list of failure modes, responses, and consequences

  11. Reliability-based maintenance evaluations and standard preventive maintenance programs

    International Nuclear Information System (INIS)

    Varno, M.; McKinley, M.

    1993-01-01

    Due to recent issuance of 10CFR50.65, the U.S. Nuclear Regulatory Commission maintenance rule (Rule), and the open-quotes Industry Guideline for Monitoring the Effectiveness of Maintenance at Nuclear Power Plantsclose quotes prepared by the Nuclear Management and Resources Council, many utilities are undertaking review or evaluation of current preventive maintenance (PM) programs. Although PM optimization and documentation are not specifically required by the Rule, an appropriate and effective PM program (PMP) will be the cornerstone of the successful and cost-effective implementation of the Rule. Currently, a project is being conducted at the Vermont Yankee Nuclear Power Station (VYNPS) in conjunction with Quadrex Energy Services to evaluate, optimize, and document the PMP. The project began in March 1993 and is scheduled for completion in mid-1995. The initial scope for the project is the evaluation of those structures, systems, and components that are within the scope of the Rule. Because of the number of systems to be evaluated (∼50), the desired completion schedule, and cost considerations, a streamlined approach to PM optimization and documentation is being utilized

  12. Reliability study: maintenance facilities Portsmouth Gaseous Diffusion Plant

    International Nuclear Information System (INIS)

    Post, B.E.; Sikorski, P.A.; Fankell, R.; Johnson, O.; Ferryman, D.S.; Miller, R.L.; Gearhart, E.C.; Rafferty, M.J.

    1981-08-01

    A reliability study of the maintenance facilities at the Portsmouth Gaseous Diffusion Plant has been completed. The reliability study team analyzed test data and made visual inspections of each component contributing to the overall operation of the facilities. The impacts of facilities and equipment failures were given consideration with regard to personnel safety, protection of government property, health physics, and environmental control. This study revealed that the maintenance facilities are generally in good condition. After evaluating the physical condition and technology status of the major components, the study team made several basic recommendations. Implementation of the recommendations proposed in this report will help assure reliable maintenance of the plant through the year 2000

  13. Offshore wind turbines reliability, availability and maintenance

    CERN Document Server

    Tavner, Peter

    2012-01-01

    The first book to specifically focus on offshore wind turbine technology and which addresses practically wind turbine reliability and availability. The book draws on the author's experience of power generation reliability and availability and the condition monitoring of that plant to describe the problems facing the developers of offshore wind farms and the solutions available to them to raise availability, reduce cost of energy and improve through life cost.

  14. Reliability-based performance simulation for optimized pavement maintenance

    International Nuclear Information System (INIS)

    Chou, Jui-Sheng; Le, Thanh-Son

    2011-01-01

    Roadway pavement maintenance is essential for driver safety and highway infrastructure efficiency. However, regular preventive maintenance and rehabilitation (M and R) activities are extremely costly. Unfortunately, the funds available for the M and R of highway pavement are often given lower priority compared to other national development policies, therefore, available funds must be allocated wisely. Maintenance strategies are typically implemented by optimizing only the cost whilst the reliability of facility performance is neglected. This study proposes a novel algorithm using multi-objective particle swarm optimization (MOPSO) technique to evaluate the cost-reliability tradeoff in a flexible maintenance strategy based on non-dominant solutions. Moreover, a probabilistic model for regression parameters is employed to assess reliability-based performance. A numerical example of a highway pavement project is illustrated to demonstrate the efficacy of the proposed MOPSO algorithms. The analytical results show that the proposed approach can help decision makers to optimize roadway maintenance plans. - Highlights: →A novel algorithm using multi-objective particle swarm optimization technique. → Evaluation of the cost-reliability tradeoff in a flexible maintenance strategy. → A probabilistic model for regression parameters is employed to assess reliability-based performance. → The proposed approach can help decision makers to optimize roadway maintenance plans.

  15. Reliability-based performance simulation for optimized pavement maintenance

    Energy Technology Data Exchange (ETDEWEB)

    Chou, Jui-Sheng, E-mail: jschou@mail.ntust.edu.tw [Department of Construction Engineering, National Taiwan University of Science and Technology (Taiwan Tech), 43 Sec. 4, Keelung Rd., Taipei 106, Taiwan (China); Le, Thanh-Son [Department of Construction Engineering, National Taiwan University of Science and Technology (Taiwan Tech), 43 Sec. 4, Keelung Rd., Taipei 106, Taiwan (China)

    2011-10-15

    Roadway pavement maintenance is essential for driver safety and highway infrastructure efficiency. However, regular preventive maintenance and rehabilitation (M and R) activities are extremely costly. Unfortunately, the funds available for the M and R of highway pavement are often given lower priority compared to other national development policies, therefore, available funds must be allocated wisely. Maintenance strategies are typically implemented by optimizing only the cost whilst the reliability of facility performance is neglected. This study proposes a novel algorithm using multi-objective particle swarm optimization (MOPSO) technique to evaluate the cost-reliability tradeoff in a flexible maintenance strategy based on non-dominant solutions. Moreover, a probabilistic model for regression parameters is employed to assess reliability-based performance. A numerical example of a highway pavement project is illustrated to demonstrate the efficacy of the proposed MOPSO algorithms. The analytical results show that the proposed approach can help decision makers to optimize roadway maintenance plans. - Highlights: > A novel algorithm using multi-objective particle swarm optimization technique. > Evaluation of the cost-reliability tradeoff in a flexible maintenance strategy. > A probabilistic model for regression parameters is employed to assess reliability-based performance. > The proposed approach can help decision makers to optimize roadway maintenance plans.

  16. Reliability in maintenance and design of elastomer sealed closures

    International Nuclear Information System (INIS)

    Lake, W.H.

    1978-01-01

    The methods of reliability are considered for maintenance and design of elastomer sealed containment closures. Component reliability is used to establish a replacement schedule for system maintenance. Reliability data on elastomer seals is used to evaluate the common practice of annual replacement, and to calculate component reliability values for several typical shipment time periods. System reliability methods are used to examine the relative merits of typical closure designs. These include single component and redundant seal closure, with and without closure verification testing. The paper presents a general method of quantifying the merits of closure designs through the use of reliability analysis, which is a probabilistic technique. The reference list offers a general source of information in the field of reliability, and should offer the opportunity to extend the procedures discussed in this paper to other design safety applications

  17. Imperfect Preventive Maintenance Model Study Based On Reliability Limitation

    Directory of Open Access Journals (Sweden)

    Zhou Qian

    2016-01-01

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

  18. 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...

  19. Reliability analysis of maintenance operations for railway tracks

    International Nuclear Information System (INIS)

    Rhayma, N.; Bressolette, Ph.; Breul, P.; Fogli, M.; Saussine, G.

    2013-01-01

    Railway engineering is confronted with problems due to degradation of the railway network that requires important and costly maintenance work. However, because of the lack of knowledge on the geometrical and mechanical parameters of the track, it is difficult to optimize the maintenance management. In this context, this paper presents a new methodology to analyze the behavior of railway tracks. It combines new diagnostic devices which permit to obtain an important amount of data and thus to make statistics on the geometric and mechanical parameters and a non-intrusive stochastic approach which can be coupled with any mechanical model. Numerical results show the possibilities of this methodology for reliability analysis of different maintenance operations. In the future this approach will give important informations to railway managers to optimize maintenance operations using a reliability analysis

  20. Equipment reliability process improvement and preventive maintenance optimization

    International Nuclear Information System (INIS)

    Darragi, M.; Georges, A.; Vaillancourt, R.; Komljenovic, D.; Croteau, M.

    2004-01-01

    The Gentilly-2 Nuclear Power Plant wants to optimize its preventive maintenance program through an Integrated Equipment Reliability Process. All equipment reliability related activities should be reviewed and optimized in a systematic approach especially for aging plants such as G2. This new approach has to be founded on best practices methods with the purpose of the rationalization of the preventive maintenance program and the performance monitoring of on-site systems, structures and components (SSC). A rational preventive maintenance strategy is based on optimized task scopes and frequencies depending on their applicability, critical effects on system safety and plant availability as well as cost-effectiveness. Preventive maintenance strategy efficiency is systematically monitored through degradation indicators. (author)

  1. Maintenance management of railway infrastructures based on reliability analysis

    International Nuclear Information System (INIS)

    Macchi, Marco; Garetti, Marco; Centrone, Domenico; Fumagalli, Luca; Piero Pavirani, Gian

    2012-01-01

    Railway infrastructure maintenance plays a crucial role for rail transport. It aims at guaranteeing safety of operations and availability of railway tracks and related equipment for traffic regulation. Moreover, it is one major cost for rail transport operations. Thus, the increased competition in traffic market is asking for maintenance improvement, aiming at the reduction of maintenance expenditures while keeping the safety of operations. This issue is addressed by the methodology presented in the paper. The first step of the methodology consists of a family-based approach for the equipment reliability analysis; its purpose is the identification of families of railway items which can be given the same reliability targets. The second step builds the reliability model of the railway system for identifying the most critical items, given a required service level for the transportation system. The two methods have been implemented and tested in practical case studies, in the context of Rete Ferroviaria Italiana, the Italian public limited company for railway transportation.

  2. Planning of operation & maintenance using risk and reliability based methods

    DEFF Research Database (Denmark)

    Florian, Mihai; Sørensen, John Dalsgaard

    2015-01-01

    Operation and maintenance (OM) of offshore wind turbines contributes with a substantial part of the total levelized cost of energy (LCOE). The objective of this paper is to present an application of risk- and reliability-based methods for planning of OM. The theoretical basis is presented...

  3. Machine Maintenance Scheduling with Reliability Engineering Method and Maintenance Value Stream Mapping

    Science.gov (United States)

    Sembiring, N.; Nasution, A. H.

    2018-02-01

    Corrective maintenance i.e replacing or repairing the machine component after machine break down always done in a manufacturing company. It causes the production process must be stopped. Production time will decrease due to the maintenance team must replace or repair the damage machine component. This paper proposes a preventive maintenance’s schedule for a critical component of a critical machine of an crude palm oil and kernel company due to increase maintenance efficiency. The Reliability Engineering & Maintenance Value Stream Mapping is used as a method and a tool to analize the reliability of the component and reduce the wastage in any process by segregating value added and non value added activities.

  4. 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

  5. Application of reliability centred maintenance to optimize operation and maintenance in nuclear power plants

    International Nuclear Information System (INIS)

    2007-05-01

    In order to increase Member States capabilities in utilizing good engineering and management practices the Agency has developed a series of Technical Documents (TECDOCs) to describe best practices and members experience in the application of them. This TECDOC describes the concept of Reliability Centred Maintenance (RCM) which is the term used to describe a systematic approach to the evaluation, design and development of cost effective maintenance programmes for plant and equipment. The concept has been in existence for over 25 years originating in the civil aviation sector. This TECDOC supplements previous IAEA publications on the subject and seeks to reflect members experience in the application of the principles involved. The process focuses on the functionality of the plant and equipment and the critical failure mechanisms that could result in the loss of functionality. When employed effectively the process can result in the elimination of unnecessary maintenance activities and the identification and introduction of measures to address deficiencies in the maintenance programme. Overall the process can result in higher levels of reliability for the plant and equipment at reduced cost and demands on finite maintenance resources. The application of the process requires interaction between the operators and the maintenance practitioners which is often lacking in traditional maintenance programmes. The imposition of this discipline produces the added benefit of improved information flows between the key players in plant and equipment management with the result that maintenance activities and operational practices are better informed. This publication was produced within IAEA programme on nuclear power plants operating performance and life cycle management

  6. Technology success: Integration of power plant reliability and effective maintenance

    International Nuclear Information System (INIS)

    Ferguson, K.

    2008-01-01

    The nuclear power generation sector has a tradition of utilizing technology as a key attribute for advancement. Companies that own, manage, and operate nuclear power plants can be expected to continue to rely on technology as a vital element of success. Inherent with the operations of the nuclear power industry in many parts of the world is the close connection between efficiency of power plant operations and successful business survival. The relationship among power plant availability, reliability of systems and components, and viability of the enterprise is more evident than ever. Technology decisions need to be accomplished that reflect business strategies, work processes, as well as needs of stakeholders and authorities. Such rigor is needed to address overarching concerns such as power plant life extension and license renewal, new plant orders, outage management, plant safety, inventory management etc. Particular to power plant reliability, the prudent leveraging of technology as a key to future success is vital. A dominant concern is effective asset management as physical plant assets age. Many plants are in, or are entering in, a situation in which systems and component design life and margins are converging such that failure threats can come into play with increasing frequency. Wisely selected technologies can be vital to the identification of emerging threats to reliable performance of key plant features and initiating effective maintenance actions and investments that can sustain or enhance current reliability in a cost effective manner. This attention to detail is vital to investment in new plants as well This paper and presentation will address (1) specific technology success in place at power plants, including nuclear, that integrates attention to attaining high plant reliability and effective maintenance actions as well as (2) complimentary actions that maximize technology success. In addition, the range of benefits that accrue as a result of

  7. 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.

  8. 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.)

  9. Maintenance personnel performance simulation (MAPPS): a model for predicting maintenance performance reliability in nuclear power plants

    International Nuclear Information System (INIS)

    Knee, H.E.; Krois, P.A.; Haas, P.M.; Siegel, A.I.; Ryan, T.G.

    1983-01-01

    The NRC has developed a structured, quantitative, predictive methodology in the form of a computerized simulation model for assessing maintainer task performance. Objective of the overall program is to develop, validate, and disseminate a practical, useful, and acceptable methodology for the quantitative assessment of NPP maintenance personnel reliability. The program was organized into four phases: (1) scoping study, (2) model development, (3) model evaluation, and (4) model dissemination. The program is currently nearing completion of Phase 2 - Model Development

  10. Fuzzy Goal Programming Approach in Selective Maintenance Reliability Model

    Directory of Open Access Journals (Sweden)

    Neha Gupta

    2013-12-01

    Full Text Available 800x600 In the present paper, we have considered the allocation problem of repairable components for a parallel-series system as a multi-objective optimization problem and have discussed two different models. In first model the reliability of subsystems are considered as different objectives. In second model the cost and time spent on repairing the components are considered as two different objectives. These two models is formulated as multi-objective Nonlinear Programming Problem (MONLPP and a Fuzzy goal programming method is used to work out the compromise allocation in multi-objective selective maintenance reliability model in which we define the membership functions of each objective function and then transform membership functions into equivalent linear membership functions by first order Taylor series and finally by forming a fuzzy goal programming model obtain a desired compromise allocation of maintenance components. A numerical example is also worked out to illustrate the computational details of the method.  Normal 0 false false false EN-US X-NONE X-NONE MicrosoftInternetExplorer4

  11. Assessment of reliability and maintenance of motor operated valves at Finnish NPPS

    International Nuclear Information System (INIS)

    Laakso, K.; Haenninen, S.; Simola, K.

    1994-01-01

    This paper summarizes two studies on motor operated valve (MOV) failure and maintenance experiences in Finnish nuclear power plants. In the first study, described in section 2 of this paper, the failure reports of MOVs at Finnish BWR units from a nine years' time period were analyzed in a systematic way. The dominant failure mechanisms were identified and time-dependencies in failure occurrence were studied. This study initiated an experience based reliability centered maintenance (RCM) analysis of motor operated valve drives, which is summarized in chapter 3 of this paper. The RCM analysis resulted in the identification and proposal of the most suitable and effective maintenance tasks for consideration. 9 refs, 3 figs, 1 tab

  12. 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.

  13. Practical application of reliability engineering in detailed design and maintenance

    International Nuclear Information System (INIS)

    Barden, S.E.

    1975-01-01

    Modern plant systems are closely coupled combinations of sophisticated and expensive equipment, some important parts of which may be in the development stage (high technology sector), and simpler, crude but not necessarily cheap equipment (low technology sector). Manpower resources involved with such plant systems can also be placed in high and low technology categories (i.e. specialist design and construction staff, and production staff, respectively). Neither can operate effectively without the other, and both are equally important. A sophisticated on-line computer controlling plant or analysing fault symptoms is useless, if not unsafe, if the peripheral sensing and control equipment on plant providing input data is poorly designed and inaccurate, and/or unreliable because of inadequate maintenance. Similarly, the designer can be misled and misinformed, and subsequent design evolution can be wrongly directed, if production recors do not accurately reflect what is actually happening on the plant. The application of Reliability Technology can be counter productive if it demands more effort in the collection of data that it save in facilitating quick, correct engineering decisions, and more accurate assessments of resource requirements. Reliability Engineering techniques must be simplified to made their use widely adopted in the important low technology sector, and established in all financial and contractural procedures associated with design specification and production management. This paper develops this theme with practical examples. (author)

  14. 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.

  15. Improving nuclear power plant reliability through predictive maintenance

    International Nuclear Information System (INIS)

    Geilhausen, R.; Kunze, U.

    1996-01-01

    Maintenance strategies can be assigned to one of three categories: failure maintenance, periodic maintenance or condition-oriented maintenance. The optimum maintenance scheme can be selected on the basis of a cost-benefit analysis but the safety of life and limb or the political climate for NPP can hardly expressed in numbers. The implementation of preventive maintenance needs two preconditions: high-performance instrumentation in the form of stationary and mobile monitoring systems for the determination of the condition of the nuclear power plant components and provision of a tool that can handle both the organization of the work and the evaluation of the results obtained. (authors)

  16. After reliability centred maintenance. Preventive maintenance living program implementation at Bruce Power

    International Nuclear Information System (INIS)

    Harazim, Michael L.; Ferguson, Brian J.

    2003-01-01

    Industrial preventive maintenance (PM) programs represent a large part of plant O and M costs. PM Optimization (PMO) projects represent an effective mechanism for identifying unnecessary PM, extending PM intervals and infusing predictive maintenance (PdM) methods. However, once optimized, what process prevents the PM program from returning to a state of disarray? This is the function of a PM living program (PMLP). In 1997, an independent performance assessment identified concerns with the applicability and effectiveness of all Ontario Power Generation, Inc. (OPGI) PM programs. In response, OPGI instituted an Integrated Maintenance Program (IMP) including Reliability Centred Maintenance (RCM) and a PMLP. It should be noted that the PMLP was developed for the 3 OPGI nuclear Sites (i.e. Bruce, Pickering, and Darlington). Effective 1 May 2001, the Bruce Site has been leased to a group of investors lead by British Energy. This paper is written in historical context and therefore refers to the Bruce Site as part of OPGI. The PMLP is made up of five elements: 1) process control, 2) change control, 3) worker feedback, 4) program performance metrics, and 5) deferral module. A PMLP software tool, originally applied to Duke Energy nuclear plants, was enhanced and customized specifically for the OPGI PMLP, and then implemented at all three of OPGI's nuclear sites. The objective of the OPGI PMLP was to: Provide processes/procedures for continual optimization of all site PM tasks, Ensure effective and timely revision of PM tasks in the work management system, Ensure PM tasks remain applicable/effective at all times, Maintain and enhance PM consistency on a component, system and Site basis, Ensure that new predictive maintenance techniques are applied and integrated with the PM program, Ensure that mandated PM tasks are identified and executed, Provide a mechanism for craft feedback, Meet regulatory requirements for PM program effectiveness, and Provide PM task deferral

  17. Study on the Management for the Nuclear Power Plant Maintenance and Equipment Reliability

    International Nuclear Information System (INIS)

    Yoon, Kyeongseop; Lee, Sangheon; Kim, Myungjin; Lee, Unjang

    2015-01-01

    In our country, many studies on the regulatory policy of the plant maintenance have ever been performed since 1998, but the relevant regulatory requirements were not established yet. These background mentioned above request us to study on the regulation policy and maintenance plan to improve the safety, reliability and efficiency of NPP. To solve these problems, in this study, we deduct the management methodology for the improvement of NPP maintenance and equipment reliability that is essential to secure the safety and efficiency of the commercial NPP. For analysis the maintenance and equipment reliability management methodology in overseas NPP. We studied maintenance and equipment reliability of USA, Canada and Europe(France, England, German). We also studied status and application condition of Korean NPP maintenance management technical development. We deducted an effective maintenance methodology that is needed to Korean NPP, as a result of comparison on the technical trend of the maintenance management between overseas and Korean, such like following. - Regulation form ·Specific provision of regulation requirement and application of form that is clarifying application standard - Maintenance management methodology, Maintenance management program. This results of study could be applied for regulation policy, law and guideline establishment of NPP maintenance, operation, supervision and a system establishment for maintenance management, education data about maintenance for NPP employees

  18. Logistics Operations Management Center: Maintenance Support Baseline (LOMC-MSB)

    Science.gov (United States)

    Kurrus, R.; Stump, F.

    1995-01-01

    The Logistics Operations Management Center Maintenance Support Baseline is defined. A historical record of systems, applied to and deleted from, designs in support of future management and/or technical analysis is provided. All Flight elements, Ground Support Equipment, Facility Systems and Equipment and Test Support Equipment for which LOMC has responsibilities at Kennedy Space Center and other locations are listed. International Space Station Alpha Program documentation is supplemented. The responsibility of the Space Station Launch Site Support Office is established.

  19. 49 CFR Appendix E to Part 238 - General Principles of Reliability-Based Maintenance Programs

    Science.gov (United States)

    2010-10-01

    ... STANDARDS Pt. 238, App. E Appendix E to Part 238—General Principles of Reliability-Based Maintenance... 49 Transportation 4 2010-10-01 2010-10-01 false General Principles of Reliability-Based... the design level of safety and reliability of the equipment; (2) To restore safety and reliability to...

  20. Reliability Assessment and Reliability-Based Inspection and Maintenance of Offshore Wind Turbines

    DEFF Research Database (Denmark)

    Ramirez, José Rangel

    actions are the most relevant and effective means of control of deterioration. The risk-based inspection planning methodology, based on Bayesian decision theory, represents an important tool to identify the suitable strategy to inspect and control the deterioration in structures such as offshore wind...... performance during the life cycle. The deterioration processes, such as fatigue and corrosion, are typically affecting offshore structural systems. This damage decreases the system performance and increases the risk of failure, thus not fulfilling the established safety criteria. Inspection and maintenance...... to their offshore location, no pollution risks and low human risks since they are unmanned. This allows the allocation of lower reliability level compared to e.g. oil & gas installations. With the incursion to water depths between 20 and 50 meters, the use of jacket and tripod structures represents a feasible...

  1. Maintenance contract strategies for reliability at minimum cost

    International Nuclear Information System (INIS)

    Gamman, E.

    1992-01-01

    The conference paper deals with offshore contract philosophies concerning maintenance. The main philosophies of the contract should be built on the following key success factors: Safe operations and correct quality must be sustained at any time; the maintenance contractor should be viewed as a cooperation partner, not only as a supplier; optimum exploitation of learning curve effects and economies of scale. The paper illustrates the importance of each of them in a contract context with a few recommendations

  2. Dynamic decision-making for reliability and maintenance analysis of manufacturing systems based on failure effects

    Science.gov (United States)

    Zhang, Ding; Zhang, Yingjie

    2017-09-01

    A framework for reliability and maintenance analysis of job shop manufacturing systems is proposed in this paper. An efficient preventive maintenance (PM) policy in terms of failure effects analysis (FEA) is proposed. Subsequently, reliability evaluation and component importance measure based on FEA are performed under the PM policy. A job shop manufacturing system is applied to validate the reliability evaluation and dynamic maintenance policy. Obtained results are compared with existed methods and the effectiveness is validated. Some vague understandings for issues such as network modelling, vulnerabilities identification, the evaluation criteria of repairable systems, as well as PM policy during manufacturing system reliability analysis are elaborated. This framework can help for reliability optimisation and rational maintenance resources allocation of job shop manufacturing systems.

  3. Designing remote monitoring systems for long term maintenance and reliability

    International Nuclear Information System (INIS)

    Davis, G.E.; Johnson, G.L.; Schrader, F.D.; Stone, M.A.; Wilson, E.F.

    2001-01-01

    Full text: As part of the effort to modernize safeguards equipment, the IAEA is continuing to acquire and install equipment for upgrading obsolete surveillance systems with digital technology; and providing remote-monitoring capabilities where and when economically justified. Remote monitoring is expected to reduce inspection effort, particularly at storage facilities and reactor sites. Remote monitoring technology will not only involve surveillance, but will also include seals, sensors, and other unattended measurement equipment. LLNL's experience with the Argus Security System offers lessons for the design, deployment, and maintenance of remote monitoring systems. Argus is an integrated security system for protection of high-consequence U.S. Government assets, including nuclear materials. Argus provides secure transmission of sensor data, administrative data, and video information to support intrusion detection and access control functions. LLNL developed and deployed the Argus system on its own site in 1988. Since that time LLNL has installed, maintained, and upgraded Argus systems at several Department of Energy and Department of Defense sites in the US as well as at the original LLNL site. Argus has provided high levels of reliability and integrity, as well as reducing overall lifecycle cost through incremental improvements to hardware and software. This philosophy permits expansion of functional capability, hardware upgrade and software upgrade without system outages and with minimum outage of local functions. This presentation will describe Argus design strategies and lessons learned from the Argus program as they apply to the design, development, and maintenance of a remote monitoring network. Hardware failures, software failures, and communication outages are expected and must be addressed by astute selection of system architecture. A combination of redundancy, diversity, and effective functional allocation between field and system level components should

  4. On reliability and maintenance modelling of ageing equipment in electric power systems

    International Nuclear Information System (INIS)

    Lindquist, Tommie

    2008-04-01

    Maintenance optimisation is essential to achieve cost-efficiency, availability and reliability of supply in electric power systems. The process of maintenance optimisation requires information about the costs of preventive and corrective maintenance, as well as the costs of failures borne by both electricity suppliers and customers. To calculate expected costs, information is needed about equipment reliability characteristics and the way in which maintenance affects equipment reliability. The aim of this Ph.D. work has been to develop equipment reliability models taking the effect of maintenance into account. The research has focussed on the interrelated areas of condition estimation, reliability modelling and maintenance modelling, which have been investigated in a number of case studies. In the area of condition estimation two methods to quantitatively estimate the condition of disconnector contacts have been developed, which utilise results from infrared thermography inspections and contact resistance measurements. The accuracy of these methods were investigated in two case studies. Reliability models have been developed and implemented for SF6 circuit-breakers, disconnector contacts and XLPE cables in three separate case studies. These models were formulated using both empirical and physical modelling approaches. To improve confidence in such models a Bayesian statistical method incorporating information from the equipment design process was also developed. This method was illustrated in a case study of SF6 circuit-breaker operating rods. Methods for quantifying the effect of maintenance on equipment condition and reliability have been investigated in case studies on disconnector contacts and SF6 circuit-breakers. The input required by these methods are condition measurements and historical failure and maintenance data, respectively. This research has demonstrated that the effect of maintenance on power system equipment may be quantified using available data

  5. Effective computing algorithm for maintenance optimization of highly reliable systems

    Czech Academy of Sciences Publication Activity Database

    Briš, R.; Byczanski, Petr

    2013-01-01

    Roč. 109, č. 1 (2013), s. 77-85 ISSN 0951-8320 R&D Projects: GA MŠk(CZ) ED1.1.00/02.0070 Institutional support: RVO:68145535 Keywords : exact computing * maintenance * optimization * unavailability Subject RIV: BA - General Mathematics Impact factor: 2.048, year: 2013 http://www.sciencedirect.com/science/article/pii/S0951832012001639

  6. Efficiency evaluation of an electronic equipment: availability,reliability and maintenance

    International Nuclear Information System (INIS)

    Guyot, C.

    1966-01-01

    This concept of efficiency often called ''system effectiveness'', is presented and analyzed in terms of reliability and maintenance. It allows to define the availability factor of an electronic equipment. A procedure of evaluation is proposed. (A.L.B.)

  7. Global optimization of maintenance and surveillance testing based on reliability and probabilistic safety assessment. Research project

    International Nuclear Information System (INIS)

    Martorell, S.; Serradell, V.; Munoz, A.; Sanchez, A.

    1997-01-01

    Background, objective, scope, detailed working plan and follow-up and final product of the project ''Global optimization of maintenance and surveillance testing based on reliability and probabilistic safety assessment'' are described

  8. Utilizing reliability concepts in the development of IEEE recommended good practices for nuclear plant maintenance

    International Nuclear Information System (INIS)

    Gradin, L.P.

    1986-01-01

    This paper presents information describing the concern for nuclear power plant electrical equipment maintenance and the IEEE Nuclear Power Engineering Committee's method to address that concern. That method includes the creation of Working Group 3.3, ''Maintenance Good Practices'' which is developing specific maintenance good practice documents, supporting technical information exchange, and providing a vehicle to promote practices which can reduce cost and enhance plant safety. The foundation for that effort is the utilization of Reliability concepts

  9. Design of preventive maintenance system using the reliability engineering and maintenance value stream mapping methods in PT. XYZ

    Science.gov (United States)

    Sembiring, N.; Panjaitan, N.; Angelita, S.

    2018-02-01

    PT. XYZ is a company owned by non-governmental organizations engaged in the field of production of rubber processing becoming crumb rubber. Part of the production is supported by some of machines and interacting equipment to achieve optimal productivity. Types of the machine that are used in the production process are Conveyor Breaker, Breaker, Rolling Pin, Hammer Mill, Mill Roll, Conveyor, Shredder Crumb, and Dryer. Maintenance system in PT. XYZ is corrective maintenance i.e. repairing or replacing the engine components after the crash on the machine. Replacement of engine components on corrective maintenance causes the machine to stop operating during the production process is in progress. The result is in the loss of production time due to the operator must replace the damaged engine components. The loss of production time can impact on the production targets which were not reached and lead to high loss costs. The cost for all components is Rp. 4.088.514.505. This cost is really high just for maintaining a Mill Roll Machine. Therefore PT. XYZ is needed to do preventive maintenance i.e. scheduling engine components and improving maintenance efficiency. The used methods are Reliability Engineering and Maintenance Value Stream Mapping (MVSM). The needed data in this research are the interval of time damage to engine components, opportunity cost, labor cost, component cost, corrective repair time, preventive repair time, Mean Time To Opportunity (MTTO), Mean Time To Repair (MTTR), and Mean Time To Yield (MTTY). In this research, the critical components of Mill Roll machine are Spier, Bushing, Bearing, Coupling and Roll. Determination of damage distribution, reliability, MTTF, cost of failure, cost of preventive, current state map, and future state map are done so that the replacement time for each critical component with the lowest maintenance cost and preparation of Standard Operation Procedure (SOP) are developed. For the critical component that has been

  10. System reliability as perceived by maintenance personnel on petroleum production facilities

    International Nuclear Information System (INIS)

    Antonovsky, A.; Pollock, C.; Straker, L.

    2016-01-01

    The aim of this research was to understand the relationship between maintenance staff perceptions of organisational effectiveness and operational reliability in petroleum operations. Engineering measures exist that assess the effectiveness of maintenance and reliability of equipment. These measures are typically retrospective and may not provide insight into what impedes system reliability. Perceptions of organisational effectiveness by the workforce may provide a predictive measure that could improve our understanding of the human factors that influence system reliability. Maintenance personnel (n=133) from nine petroleum production facilities completed a survey as part of a study of human factors and maintenance reliability. 69 respondents (51.9%) provided comments to an open-ended question in the survey, and these data were analysed using Interpretive Phenomenological Analysis to extract themes. Four super-ordinate themes were identified from the analysis: 1) Communication and access to information, 2) Efficiency of current work systems, 3) Need for better workgroup support, and 4) Management impacts on the workplace. We found a significant relationship between the frequency of the four super-ordinate themes and the facility reliability level as measured by ‘Mean Time Between Failures’: χ"2(6,N=158)=16.2, p=.013. These results demonstrated that operational effectiveness might be differentiated on the basis of survey-derived perceptions of maintenance personnel. - Highlights: • Thematic analysis of survey comments provided insights into workplace reliability • Worker’s comments on reliability related to technical data on time between failures • Management decision-making was the main theme in the lower reliability workplaces • Improving efficiency was the main theme in the higher reliability workplaces • Communication and better workgroup support were themes at all reliability levels

  11. 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

  12. Reliability assessment of power pole infrastructure incorporating deterioration and network maintenance

    International Nuclear Information System (INIS)

    Ryan, Paraic C.; Stewart, Mark G.; Spencer, Nathan; Li, Yue

    2014-01-01

    There is considerable investment in timber utility poles worldwide, and there is a need to examine the structural reliability and probability based management optimisation of these power distribution infrastructure elements. The work presented in this paper builds on the existing studies in this area through assessment of both treated and untreated timber power poles, with the effects of deterioration and network maintenance incorporated in the analysis. This more realistic assessment approach, with deterioration and maintenance considered, was achieved using event-based Monte Carlo simulation. The output from the probabilistic model is used to illustrate the importance of considering network maintenance in the time-dependent structural reliability assessment of timber power poles. Under wind load, treated and untreated poles designed and maintained in accordance with existing Australian standards were found to have similar failure rates. However, untreated pole networks required approximately twice as many maintenance based pole replacements to sustain the same level of reliability. The effect of four different network maintenance strategies on infrastructure performance was also investigated herein. This assessment highlighted the fact that slight alterations to network maintenance practices can lead to significant changes in performance of timber power pole networks. - Highlights: • A time-dependent structural reliability model was developed for timber power poles. • Deterioration and network maintenance were incorporated into this event based model. • Network maintenance had a significant impact on power pole wind vulnerability. • Treated and untreated poles designed to Australian standards had similar reliability. • Minor alterations to maintenance strategies had large effects on network performance

  13. Maintenance overtime policies in reliability theory models with random working cycles

    CERN Document Server

    Nakagawa, Toshio

    2015-01-01

    This book introduces a new concept of replacement in maintenance and reliability theory. Replacement overtime, where replacement occurs at the first completion of a working cycle over a planned time, is a new research topic in maintenance theory and also serves to provide a fresh optimization technique in reliability engineering. In comparing replacement overtime with standard and random replacement techniques theoretically and numerically, 'Maintenance Overtime Policies in Reliability Theory' highlights the key benefits to be gained by adopting this new approach and shows how they can be applied to inspection policies, parallel systems and cumulative damage models. Utilizing the latest research in replacement overtime by internationally recognized experts, readers are introduced to new topics and methods, and learn how to practically apply this knowledge to actual reliability models. This book will serve as an essential guide to a new subject of study for graduate students and researchers and also provides a...

  14. Job analysis of maintenance-mechanic position for the nuclear power plant maintenance personnel reliability model

    International Nuclear Information System (INIS)

    Siegel, A.I.; Bartter, W.D.; Kopstein, F.F.

    1982-06-01

    The task list method of job survey was used. In collaboration with BWR and PWR personnel, a list of 107 tasks performed by maintenance mechanics was developed, grouped into: remove and install, test and repair, inspect and perform preventive maintenance, miscellaneous, communication, and report preparation. For each listed task, the questionnaire form inquired into: frequency of performance, task completion time, safety consequences of improper performance, and the amount of training required to perform the task proficiently. Scaled information was requested about seven abilities: (1) visual speed, accuracy, and recognition; (2) gross motor coordination; (3) fine manual dexterity; (4) strength and stamina; (5) cognition; (6) memory; and (7) problem solving required for function completion. Survey forms were distributed to 27 nuclear power plants. Thirty-one maintenance mechanics representing 17 plants returned the completed forms. Frequency of performing tasks was bimodally distributed: (1) between once a year and once every six months, and (2) about once a week. More than half of the tasks have potential risk consequences if improperly performed. The five tasks with the greatest risk implications in the case of inadequate performance were: (1) remove and install reactor and dry-well heads, (2) test and repair reactor system components, (3) remove and install pressurizer mechanical relief valves, (4) test and repair pressurizer relief valves, (5) remove and install core spray pumps, seals, and valves. Hierarchically, the public risk associated with the various functions was: (1) remove and install, (2) test and repair, (3) preventive maintenance, (4) miscellaneous tasks, (5) communication, and (6) report preparation

  15. Human-centered automation of testing, surveillance and maintenance

    International Nuclear Information System (INIS)

    Bhatt, S.C.; Sun, B.K.H.

    1991-01-01

    Manual surveillance and testing of instrumentation, control and protection systems at nuclear power plants involves system and human errors which can lead to substantial plant down time. Frequent manual testing can also contribute significantly to operation and maintenance cost. Automation technology offers potential for prudent applications at the power plant to reduce testing errors and cost. To help address the testing problems and to harness the benefit of automation application, input from utilities is obtained on suitable automation approaches. This paper includes lessens from successful past experience at a few plants where some island of automation exist. The results are summarized as a set of specifications for semi automatic testing. A human-centered automation methodology is proposed with the guidelines for optimal human/computer division of tasks given. Implementation obstacles for significant changes of testing practices are identified and methods acceptable to nuclear power plants for addressing these obstacles have been suggested

  16. Improving the reliability of emergency diesel generators through sustained maintenance

    International Nuclear Information System (INIS)

    Reddy, R.

    2000-01-01

    In Nuclear Power Stations Emergency Diesel Generators are vital safety related equipment which ensures power supply to essential equipment during loss of power. In view of their importance Reliability of Diesel generators should be very high. Since these Diesel generators are standby equipment and operate only during demand or during surveillance checks, their demand failure probability should be very low and once they operate their operational availability should be very high. Madras Atomic Power Station at Kalpakkam, India consists two pressurised heavy water Reactors each rated at 220 MWe. To supply standby power each unit has two Diesel Generators of I 500 kW capacity each. The Diesel Engine is 16 cylinder 'V' type engine and is cranked by Air starting motor and is connected to generator whose rating at 100% load is 1500 KW. During commissioning and in the initial years of operation these Diesel Generators have encountered many problems. Major problem was Diesel Engine failing to start on demand. This was due to non engagement of air motor pinion with ring gear or continued engagement air motor even after the engine had picked up speed and failure of timer to initiate multiple starts after initial incomplete starts Apart from these there were problems like fuel oil leaks, high jacket water temperatures, low fuel oil pressure trips. Another major problem was with excitation system. How these problems were dealt with thereby reducing the demand failure probability and increasing the operational availability are discussed in this paper. (author)

  17. A reliability-based preventive maintenance methodology for the projection spot welding machine

    Directory of Open Access Journals (Sweden)

    Fayzimatov Ulugbek

    2018-06-01

    Full Text Available An effective operations of a projection spot welding (PSW machine is closely related to the effec-tiveness of the maintenance. Timely maintenance can prevent failures and improve reliability and maintainability of the machine. Therefore, establishing the maintenance frequency for the welding machine is one of the most important tasks for plant engineers. In this regard, reliability analysis of the welding machine can be used to establish preventive maintenance intervals (PMI and to identify the critical parts of the system. In this reliability and maintainability study, analysis of the PSW machine was carried out. The failure and repair data for analysis were obtained from automobile manufacturing company located in Uzbekistan. The machine was divided into three main sub-systems: electrical, pneumatic and hydraulic. Different distributions functions for all sub-systems was tested and their parameters tabulated. Based on estimated parameters of the analyzed distribu-tions, PMI for the PSW machines sub-systems at different reliability levels was calculated. Finally, preventive measures for enhancing the reliability of the PSW machine sub-systems are suggested.

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

    International Nuclear Information System (INIS)

    Spekkens, P.

    2012-01-01

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

  19. Status and problem for Nuclear Power Plant Maintenance Training Center

    International Nuclear Information System (INIS)

    Nanjoh, Takuo

    1991-01-01

    The Nuclear Power Plant Maintenance Training Center of Kansai Electric Power Co., Inc. was founded in October, 1983, and seven years elapsed since then. The education and training of 37,000 persons were carried out to meet the situation in the plants and to enhance the facilities. Though the main policy of the practical training for preventing the recurrence of troubles does not change, the situation changed from the time of the foundation, and the role has expanded, including PA activities. The see-through plant model installed for technical education in April, 1989 is the about 1/25 scale model of the actual machine with two loops, which actually generates steam and slight electric power, and is useful for promoting the understanding of nuclear power generation theory. It accomplishes the important role that the visitors to the Center (7500 persons in 1989 fiscal year) understand the mechanism of nuclear power generation. In 1990, the education curriculum, the method of education, the time of education and so on are reviewed, aiming at the improvement of education. The execution of education and training, the training of practical techniques, the reflection of the examples of troubles to education, and the expansion of facilities are reported. (K.I.)

  20. Stochastic reliability and maintenance modeling essays in honor of Professor Shunji Osaki on his 70th birthday

    CERN Document Server

    Nakagawa, Toshio

    2013-01-01

    In honor of the work of Professor Shunji Osaki, Stochastic Reliability and Maintenance Modeling provides a comprehensive study of the legacy of and ongoing research in stochastic reliability and maintenance modeling. Including associated application areas such as dependable computing, performance evaluation, software engineering, communication engineering, distinguished researchers review and build on the contributions over the last four decades by Professor Shunji Osaki. Fundamental yet significant research results are presented and discussed clearly alongside new ideas and topics on stochastic reliability and maintenance modeling to inspire future research. Across 15 chapters readers gain the knowledge and understanding to apply reliability and maintenance theory to computer and communication systems. Stochastic Reliability and Maintenance Modeling is ideal for graduate students and researchers in reliability engineering, and workers, managers and engineers engaged in computer, maintenance and management wo...

  1. A Study on the Joint Reliability Importance with Applications to the Maintenance Policy

    Energy Technology Data Exchange (ETDEWEB)

    Hong, Jung Sik; Kwon, Hong Je; Song, Mi Ja; Kim, Woong Kil; Yoong, Do Hwa [Seoul National Polytechnic University, Seoul (Korea, Republic of); Moon, Sin Myung; Cho, Bong Je; Moon, Jae Phil; Koo, Hoon Young; Lee, Jin Seung [Seoul National University, Seoul (Korea, Republic of)

    1997-09-01

    The objective of this project is to investigate the possibility of applying the Joint Reliability Importance(JRI) of two components to the establishment of system maintenance policy. Components are classified into reliability substitutes and reliability compliments. If the sign of JRI of two components is positive, they are called as reliability compliments. If the sign of JRI of two components is negative, they are called as reliability substitutes. In case of reliability compliments, one component becomes more important as the other one works and in case of reliability substitutes, one component becomes more important as the other one fails. Therefore, when the preventive maintenance is carried out, two components which are reliability substitutes should not be maintained at the same time. Also, when the corrective maintenance is carried out, we not only repair the failed components but pay attention to the functioning components which are reliability substitutes with respect to the failed components. The sign of JRI of any two components in series (parallel) system is positive (negative). Then, what is the sign of any two components in k-out-of-n:G system? This project presents an idea of characterizing the k-out-of-n:G system by calculating the JRI of two components in that system, assuming that reliability of all components are equal. In addition to the JRI of two components, JRI of two gates is introduced in this project. The algorithm to compute the JRI of two gates is presented. Bridge system is considered and the co-relation of two min cut sets is illustrated by using the cut-set representation of bridge system and calculating the JRI of two gates. 28 refs., 20 tabs., 32 figs. (author)

  2. A methodology based in particle swarm optimization algorithm for preventive maintenance focused in reliability and cost

    International Nuclear Information System (INIS)

    Luz, Andre Ferreira da

    2009-01-01

    In this work, a Particle Swarm Optimization Algorithm (PSO) is developed for preventive maintenance optimization. The proposed methodology, which allows the use flexible intervals between maintenance interventions, instead of considering fixed periods (as usual), allows a better adaptation of scheduling in order to deal with the failure rates of components under aging. Moreover, because of this flexibility, the planning of preventive maintenance becomes a difficult task. Motivated by the fact that the PSO has proved to be very competitive compared to other optimization tools, this work investigates the use of PSO as an alternative tool of optimization. Considering that PSO works in a real and continuous space, it is a challenge to use it for discrete optimization, in which scheduling may comprise variable number of maintenance interventions. The PSO model developed in this work overcome such difficulty. The proposed PSO searches for the best policy for maintaining and considers several aspects, such as: probability of needing repair (corrective maintenance), the cost of such repairs, typical outage times, costs of preventive maintenance, the impact of maintaining the reliability of systems as a whole, and the probability of imperfect maintenance. To evaluate the proposed methodology, we investigate an electro-mechanical system consisting of three pumps and four valves, High Pressure Injection System (HPIS) of a PWR. Results show that PSO is quite efficient in finding the optimum preventive maintenance policies for the HPIS. (author)

  3. Reliability and Maintenance for Offshore Wind Turbines and Wave Energy Devices

    DEFF Research Database (Denmark)

    Sørensen, John Dalsgaard

    2015-01-01

    Wind turbines are in some countries contributing significantly the production of electricity and wave energy devices have the potential to be developed in a similarway. For both offshore wind turbines and wave energy devices reliability is a key issue since costs to operation and maintenance may...... be significant contributors to the Levelized Cost Of Energy and OM costs are highly dependent on the reliability of the components implying that it is important to focus on increasing the reliability as much as is economically reasonable. This paper describes basic aspects for reliability analysis of wind...... turbines and wave energy devices with special focus on structural components. The reliability assessment needs include the effects of the control system and possible faults due to failure of electrical/mechanical components and e.g. loss of grid connection. The target reliability level for wind turbine...

  4. Reliability and risk-based planning of operation and maintenance of offshore wind turbines

    DEFF Research Database (Denmark)

    Sørensen, John Dalsgaard; Florian, Mihai; Berzonskis, Arvydas

    2016-01-01

    costly (and safe), and it is important to include in the reliability assessment the information obtained during operation (from condition monitoring and inspections) and the maintenance performed (incl. repairs and replacements). The paper presents a risk-based approach for optimal planning of Operation...

  5. Reliability analysis and risk-based methods for planning of operation & maintenance of offshore wind turbines

    DEFF Research Database (Denmark)

    Sørensen, John Dalsgaard

    2017-01-01

    for extreme and fatigue limit states are presented. Operation & Maintenance planning often follows corrective and preventive strategies based on information from condition monitoring and structural health monitoring systems. A reliability- and risk-based approach is presented where a life-cycle approach...

  6. From reliability to maintenance of emergency generator sets in nuclear plants

    International Nuclear Information System (INIS)

    Reyraud, Y.

    1986-01-01

    The particular conditions of operation of emergency generator sets in a nuclear energy plant induce to take up a strategy of supervision and of maintenance very different of the one recommended for production generator sets. Mechanical and thermal pulls are affected by the size of the set and the choice of rotation running in respect of the wanted power and the response time requirements for the security of nuclear reactor. Reliability studies are helpful to define the strategy of supervision tests. The importance of the number of starts with respect to the running time requires the introduction of the idea of equivalent hours for the definition of maintenance periods. The security of the equipment and the upholding of the reliability at a value close to the optimum impose rigorous choices and strict conditions of supervision and maintenance [fr

  7. Reliability Assessment and Reliability-Based Inspection and Maintenance of Offshore Wind Turbines

    DEFF Research Database (Denmark)

    Ramírez, José G. Rangel; Sørensen, John Dalsgaard

    2009-01-01

    Probabilistic methodologies represent an important tool to identify the suitable strategy to inspect and deal with the deterioration in structures such as offshore wind turbines (OWT). Reliability based methods such as Risk Based Inspection (RBI) planning may represent a proper methodology to opt...

  8. MAPPS (Maintenance Personnel Performance Simulation): a computer simulation model for human reliability analysis

    International Nuclear Information System (INIS)

    Knee, H.E.; Haas, P.M.

    1985-01-01

    A computer model has been developed, sensitivity tested, and evaluated capable of generating reliable estimates of human performance measures in the nuclear power plant (NPP) maintenance context. The model, entitled MAPPS (Maintenance Personnel Performance Simulation), is of the simulation type and is task-oriented. It addresses a number of person-machine, person-environment, and person-person variables and is capable of providing the user with a rich spectrum of important performance measures including mean time for successful task performance by a maintenance team and maintenance team probability of task success. These two measures are particularly important for input to probabilistic risk assessment (PRA) studies which were the primary impetus for the development of MAPPS. The simulation nature of the model along with its generous input parameters and output variables allows its usefulness to extend beyond its input to PRA

  9. Nuclear power plant maintenance personnel reliability prediction (NPP/MPRP) effort at Oak Ridge National Laboratory

    International Nuclear Information System (INIS)

    Knee, H.E.; Haas, P.M.; Siegel, A.I.

    1981-01-01

    Human errors committed during maintenance activities are potentially a major contribution to the overall risk associated with the operation of a nuclear power plant (NPP). An NRC-sponsored program at Oak Ridge National Laboratory is attempting to develop a quantitative predictive technique to evaluate the contribution of maintenance errors to the overall NPP risk. The current work includes a survey of the requirements of potential users to ascertain the need for and content of the proposed quantitative model, plus an initial job/task analysis to determine the scope and applicability of various maintenance tasks. In addition, existing human reliability prediction models are being reviewed and assessed with respect to their applicability to NPP maintenance tasks. This paper discusses the status of the program and summarizes the results to date

  10. Failure and Maintenance Analysis Using Web-Based Reliability Database System

    International Nuclear Information System (INIS)

    Hwang, Seok Won; Kim, Myoung Su; Seong, Ki Yeoul; Na, Jang Hwan; Jerng, Dong Wook

    2007-01-01

    Korea Hydro and Nuclear Power Company has lunched the development of a database system for PSA and Maintenance Rule implementation. It focuses on the easy processing of raw data into a credible and useful database for the risk-informed environment of nuclear power plant operation and maintenance. Even though KHNP had recently completed the PSA for all domestic NPPs as a requirement of the severe accident mitigation strategy, the component failure data were only gathered as a means of quantification purposes for the relevant project. So, the data were not efficient enough for the Living PSA or other generic purposes. Another reason to build a real time database is for the newly adopted Maintenance Rule, which requests the utility to continuously monitor the plant risk based on its operation and maintenance performance. Furthermore, as one of the pre-condition for the Risk Informed Regulation and Application, the nuclear regulatory agency of Korea requests the development and management of domestic database system. KHNP is stacking up data of operation and maintenance on the Enterprise Resource Planning (ERP) system since its first opening on July, 2003. But, so far a systematic review has not been performed to apply the component failure and maintenance history for PSA and other reliability analysis. The data stored in PUMAS before the ERP system is introduced also need to be converted and managed into the new database structure and methodology. This reliability database system is a web-based interface on a UNIX server with Oracle relational database. It is designed to be applicable for all domestic NPPs with a common database structure and the web interfaces, therefore additional program development would not be necessary for data acquisition and processing in the near future. Categorization standards for systems and components have been implemented to analyze all domestic NPPs. For example, SysCode (for a system code) and CpCode (for a component code) were newly

  11. Age-dependent reliability model considering effects of maintenance and working conditions

    International Nuclear Information System (INIS)

    Martorell, Sebastian; Sanchez, Ana; Serradell, Vicente

    1999-01-01

    Nowadays, there is some doubt about building new nuclear power plants (NPPs). Instead, there is a growing interest in analyzing the possibility to extend current NPP operation, where life management programs play an important role. The evolution of the NPP safety depends on the evolution of the reliability of its safety components, which, in turn, is a function of their age along the NPP operational life. In this paper, a new age-dependent reliability model is presented, which includes parameters related to surveillance and maintenance effectiveness and working conditions of the equipment, both environmental and operational. This model may be used to support NPP life management and life extension programs, by improving or optimizing surveillance and maintenance tasks using risk and cost models based on such an age-dependent reliability model. The results of the sensitivity study in the example application show that the selection of the most appropriate maintenance strategy would directly depend on the previous parameters. Then, very important differences are expected to appear under certain circumstances, particularly, in comparison with other models that do not consider maintenance effectiveness and working conditions simultaneously

  12. History of Reliability and Quality Assurance at Kennedy Space Center

    Science.gov (United States)

    Childers, Frank M.

    2004-01-01

    This Kennedy Historical Document (KHD) provides a unique historical perspective of the organizational and functional responsibilities for the manned and un-manned programs at Kennedy Space Center, Florida. As systems become more complex and hazardous, the attention to detailed planning and execution continues to be a challenge. The need for a robust reliability and quality assurance program will always be a necessity to ensure mission success. As new space missions are defined and technology allows for continued access to space, these programs cannot be compromised. The organizational structure that has provided the reliability and quality assurance functions for both the manned and unmanned programs has seen many changes since the first group came to Florida in the 1950's. The roles of government and contractor personnel have changed with each program and organizational alignment has changed based on that responsibility. The organizational alignment of the personnel performing these functions must ensure independent assessment of the processes.

  13. Modeling the reliability and maintenance costs of wind turbines using Weibull analysis

    Energy Technology Data Exchange (ETDEWEB)

    Vachon, W.A. [W.A. Vachon & Associates, Inc., Manchester, MA (United States)

    1996-12-31

    A general description is provided of the basic mathematics and use of Weibull statistical models for modeling component failures and maintenance costs as a function of time. The applicability of the model to wind turbine components and subsystems is discussed with illustrative examples of typical component reliabilities drawn from actual field experiences. Example results indicate the dominant role of key subsystems based on a combination of their failure frequency and repair/replacement costs. The value of the model is discussed as a means of defining (1) maintenance practices, (2) areas in which to focus product improvements, (3) spare parts inventory, and (4) long-term trends in maintenance costs as an important element in project cash flow projections used by developers, investors, and lenders. 6 refs., 8 figs., 3 tabs.

  14. Managing wind turbine reliability and maintenance via performance-based contract

    DEFF Research Database (Denmark)

    Jin, Tongdan; Ding, Yi; Guo, Huairui

    2012-01-01

    between system cost, reliability and spare parts stocking. This analytical insight into the system performance allows the turbine manufacturer to optimize design, production, and after-sales services. The study aims to create a theoretical basis to facilitate the transition of the maintenance paradigm......Performance-based contracting (PBC) is reshaping the acquisition, operation, and maintenance of capital equipment. Under the PBC scheme, we propose a holistic approach for lowering the cost of wind turbine ownership while meeting the availability requirement. Our effects are focused on integrated...... firms who design and market wind turbines, and also provide maintenance and repair service. PBC differs from conventional service contracts in that the wind farmers compensate the service provider for the system performance, not the spare parts and repair labor. We explore the analytical relationship...

  15. Reliability And Maintenance Analysis Of CCTV Systems Used In Rail Transport

    OpenAIRE

    Siergiejczyk Mirosław; Paś Jacek; Rosiński Adam

    2015-01-01

    CCTV systems are widely used across plethora of industrial areas including transport, where their function is to support transport telematics systems. Among others, they are used to ensure travel safety. This paper presented a reliability and maintenance analysis of CCTV. It led to building a relationships graph and then Chapman–Kolmogorov system of equations was derived to describe it. Drawing on those equations, relationships for calculating probability of system staying in state of full ab...

  16. Benchmarking of the maintenance cost in HEPT Centers

    CERN Document Server

    Béjar-Alonso, Isabel; Rühl, I; CERN. Geneva. ST Division

    2002-01-01

    This article is the follow up of the paper "Analyse of maintenance cost in ST" presented at the 4th Workshop in Chamonix. Last year the equipment was grouped into families and the ratio of the maintenance cost over the replacement value for each family was calculated. This was done to make an evaluation of the level of maintenance compared with other similar laboratories. This paper shows the result of this comparison. The paper tries to highlight the problem evaluating the level of maintenance and the use of resources. With scarce resources available the division has to make sure that they are allocated and followed up in the best possible and optimal way. "Input" or "quantitative" measurements will therefore have to be combined with performance indicators. This is the only way to measure and evaluate the effect the use of resources has on the output

  17. Maintenance strategy for tilting table of rolling mill based on reliability considerations

    International Nuclear Information System (INIS)

    Deshpande, V.S.; Modak, J.P.

    2003-01-01

    Reliability centred maintenance (RCM) is a new strategic framework for ensuring that any asset continues to perform, as its users want it to perform. RCM is a process used to determine the maintenance requirement of any physical asset in its operating context. RCM process entails asking seven questions about each of the selected assets. It makes use of two documents namely, RCM information worksheet and RCM decision worksheet. RCM decision diagram integrates all the decision processes into a single strategic framework. RCM concept developed by US commercial airlines industry has been successfully implemented by Military, Navy, Nuclear power plants, electric power generation and distribution undertakings and several other sectors. These projects have been carried out in the United Kingdom, The Republic of Ireland, the United States, Hong Kong, Australia, Spain and Singapore. The fact that people has enthusiastically received RCM at all levels and has enabled users to achieve some remarkable successes in all of these countries, suggests that it can be universally employed. Literature review indicates that RCM approach is not conventionally applied in process industries in India. Presently, predictive maintenance (PDM) approach along with conventional preventive maintenance is used in continuous/process industries. This approach if implemented in totality will increase the production cost to a large degree and make the production uneconomical. Similarly breakdown maintenance (BDM) approach cannot be applied in such industries as each breakdown involves huge costs. RCM approach is a compromise between PDM and BDM approach for optimising the cost and ensuring the availability of machine. The RCM approach has been applied to the tilting table system of rolling mill for the research work reported in this paper. In the present study, preventive maintenance tasks suggested for power transmission subsystem, guiding and transportation subsystem and hydraulic subsystem in

  18. Reliability Centred Maintenance (RCM) Analysis of Laser Machine in Filling Lithos at PT X

    Science.gov (United States)

    Suryono, M. A. E.; Rosyidi, C. N.

    2018-03-01

    PT. X used automated machines which work for sixteen hours per day. Therefore, the machines should be maintained to keep the availability of the machines. The aim of this research is to determine maintenance tasks according to the cause of component’s failure using Reliability Centred Maintenance (RCM) and determine the amount of optimal inspection frequency which must be performed to the machine at filling lithos process. In this research, RCM is used as an analysis tool to determine the critical component and find optimal inspection frequencies to maximize machine’s reliability. From the analysis, we found that the critical machine in filling lithos process is laser machine in Line 2. Then we proceed to determine the cause of machine’s failure. Lastube component has the highest Risk Priority Number (RPN) among other components such as power supply, lens, chiller, laser siren, encoder, conveyor, and mirror galvo. Most of the components have operational consequences and the others have hidden failure consequences and safety consequences. Time-directed life-renewal task, failure finding task, and servicing task can be used to overcome these consequences. The results of data analysis show that the inspection must be performed once a month for laser machine in the form of preventive maintenance to lowering the downtime.

  19. Maintenance strategy based on reliability functions for an oil centrifugal pump

    Directory of Open Access Journals (Sweden)

    Denis Carlos Mengue

    2013-06-01

    Full Text Available The purpose of this article was to define the most appropriate maintenance strategy for a centrifugal pump (preventive, predictive, corrective or emergency, based on reliability calculation. The research method was the quantitative modeling, applied in a petroleum plant. The study may contribute to the development of a strategic model for the management of the industrial plant maintenance. In the company's information system, records of eleven years have been gathered on times between failures and times for repair of the equipment. These times were modeled by probability distributions. From the results obtained were calculated Reliability and Maintainability functions R(t and M(t. By combining their expected values (MTBF and MTTR, Av availability was calculated. The figures for MTBF, MTTR and Av were respectively 3,936 hours, 133 hours and 96.73%. The most likely shape factor of the Weibull distribution which modeled the time between failures was 0.69. So, it was possible to affirm that the pump is in the infant mortality phase. The theoretical framework of RCM indicated corrective  maintenance as the strategy for the item. This strategy aims to eliminate the defects of equipment design, reinforce items that usually break and remove the causes of the failures.

  20. A reliability-based maintenance technicians' workloads optimisation model with stochastic consideration

    Science.gov (United States)

    Ighravwe, D. E.; Oke, S. A.; Adebiyi, K. A.

    2016-06-01

    The growing interest in technicians' workloads research is probably associated with the recent surge in competition. This was prompted by unprecedented technological development that triggers changes in customer tastes and preferences for industrial goods. In a quest for business improvement, this worldwide intense competition in industries has stimulated theories and practical frameworks that seek to optimise performance in workplaces. In line with this drive, the present paper proposes an optimisation model which considers technicians' reliability that complements factory information obtained. The information used emerged from technicians' productivity and earned-values using the concept of multi-objective modelling approach. Since technicians are expected to carry out routine and stochastic maintenance work, we consider these workloads as constraints. The influence of training, fatigue and experiential knowledge of technicians on workload management was considered. These workloads were combined with maintenance policy in optimising reliability, productivity and earned-values using the goal programming approach. Practical datasets were utilised in studying the applicability of the proposed model in practice. It was observed that our model was able to generate information that practicing maintenance engineers can apply in making more informed decisions on technicians' management.

  1. 20 CFR 638.306 - Protection and maintenance of contract center facilities owned or leased by Job Corps.

    Science.gov (United States)

    2010-04-01

    ... 20 Employees' Benefits 3 2010-04-01 2010-04-01 false Protection and maintenance of contract center... Funding, Site Selection, and Facilities Management § 638.306 Protection and maintenance of contract center... and maintenance of contract center facilities owned or leased by Job Corps which shall be consistent...

  2. Wind turbine reliability :understanding and minimizing wind turbine operation and maintenance costs.

    Energy Technology Data Exchange (ETDEWEB)

    Walford, Christopher A. (Global Energy Concepts. Kirkland, WA)

    2006-03-01

    Wind turbine system reliability is a critical factor in the success of a wind energy project. Poor reliability directly affects both the project's revenue stream through increased operation and maintenance (O&M) costs and reduced availability to generate power due to turbine downtime. Indirectly, the acceptance of wind-generated power by the financial and developer communities as a viable enterprise is influenced by the risk associated with the capital equipment reliability; increased risk, or at least the perception of increased risk, is generally accompanied by increased financing fees or interest rates. This paper outlines the issues relevant to wind turbine reliability for wind turbine power generation projects. The first sections describe the current state of the industry, identify the cost elements associated with wind farm O&M and availability and discuss the causes of uncertainty in estimating wind turbine component reliability. The latter sections discuss the means for reducing O&M costs and propose O&M related research and development efforts that could be pursued by the wind energy research community to reduce cost of energy.

  3. Non-periodic preventive maintenance with reliability thresholds for complex repairable systems

    International Nuclear Information System (INIS)

    Lin, Zu-Liang; Huang, Yeu-Shiang; Fang, Chih-Chiang

    2015-01-01

    In general, a non-periodic condition-based PM policy with different condition variables is often more effective than a periodic age-based policy for deteriorating complex repairable systems. In this study, system reliability is estimated and used as the condition variable, and three reliability-based PM models are then developed with consideration of different scenarios which can assist in evaluating the maintenance cost for each scenario. The proposed approach provides the optimal reliability thresholds and PM schedules in advance by which the system availability and quality can be ensured and the organizational resources can be well prepared and managed. The results of the sensitivity anlysis indicate that PM activities performed at a high reliability threshold can not only significantly improve the system availability but also efficiently extend the system lifetime, although such a PM strategy is more costly than that for a low reliabiltiy threshold. The optimal reliability threshold increases along with the number of PM activities to prevent future breakdowns caused by severe deterioration, and thus substantially reduces repair costs. - Highlights: • The PM problems for repairable deteriorating systems are formulated. • The structural properties of the proposed PM models are investigated. • The corresponding algorithms to find the optimal PM strategies are provided. • Imperfect PM activities are allowed to reduce the occurences of breakdowns. • Provide managers with insights about the critical factors in the planning stage

  4. On preventive maintenance policy of a critical reliability level for system subject to degradation

    International Nuclear Information System (INIS)

    Zhao, Y.X.

    2003-01-01

    Conventional preventive maintenance (PM) policies generally hold same time interval for PM actions and are often applied with known failure modes. The same time interval will give unavoidably decreasing reliabilities at the PM actions for degradation system with imperfect PM effect and the known failure modes may be inaccurate in practice. Therefore, field managers would prefer policy with an acceptable reliability level to keep system often at a good state. A PM policy with the critical reliability level is presented to address the preference of field managers. Through assuming that system after a PM action starts a new failure process, a parameter so-called degradation ratio is introduced to represent the imperfect effect. The policy holds a law that there is same number of failures in the time intervals of various PM cycles, and same degradation ratio for the system reliability or benefit parameters such as the optimal time intervals and the hazard rates between the neighboring PM cycles. This law is valid to any of the failure modes that could be appropriately referred as a 'general isodegrading model', and the degradation ratio as a 'general isodegrading ratio'. In addition, life cycle availability and cost functions are derived for system with the policy. An analysis of the field data of a loading and unloading machine indicates that the reliability, availability and cost in life cycle might be well modeled by the present theory and approach

  5. Relevance of control theory to design and maintenance problems in time-variant reliability: The case of stochastic viability

    International Nuclear Information System (INIS)

    Rougé, Charles; Mathias, Jean-Denis; Deffuant, Guillaume

    2014-01-01

    The goal of this paper is twofold: (1) to show that time-variant reliability and a branch of control theory called stochastic viability address similar problems with different points of view, and (2) to demonstrate the relevance of concepts and methods from stochastic viability in reliability problems. On the one hand, reliability aims at evaluating the probability of failure of a system subjected to uncertainty and stochasticity. On the other hand, viability aims at maintaining a controlled dynamical system within a survival set. When the dynamical system is stochastic, this work shows that a viability problem belongs to a specific class of design and maintenance problems in time-variant reliability. Dynamic programming, which is used for solving Markovian stochastic viability problems, then yields the set of design states for which there exists a maintenance strategy which guarantees reliability with a confidence level β for a given period of time T. Besides, it leads to a straightforward computation of the date of the first outcrossing, informing on when the system is most likely to fail. We illustrate this approach with a simple example of population dynamics, including a case where load increases with time. - Highlights: • Time-variant reliability tools cannot devise complex maintenance strategies. • Stochastic viability is a control theory that computes a probability of failure. • Some design and maintenance problems are stochastic viability problems. • Used in viability, dynamic programming can find reliable maintenance actions. • Confronting reliability and control theories such as viability is promising

  6. Reliability And Maintenance Analysis Of CCTV Systems Used In Rail Transport

    Directory of Open Access Journals (Sweden)

    Siergiejczyk Mirosław

    2015-11-01

    Full Text Available CCTV systems are widely used across plethora of industrial areas including transport, where their function is to support transport telematics systems. Among others, they are used to ensure travel safety. This paper presented a reliability and maintenance analysis of CCTV. It led to building a relationships graph and then Chapman–Kolmogorov system of equations was derived to describe it. Drawing on those equations, relationships for calculating probability of system staying in state of full ability SPZ, state of the impendency over safety SZB1 as well as state of unreliability of safety SB were derived.

  7. Reliability-based optimization of maintenance scheduling of mechanical components under fatigue

    Science.gov (United States)

    Beaurepaire, P.; Valdebenito, M.A.; Schuëller, G.I.; Jensen, H.A.

    2012-01-01

    This study presents the optimization of the maintenance scheduling of mechanical components under fatigue loading. The cracks of damaged structures may be detected during non-destructive inspection and subsequently repaired. Fatigue crack initiation and growth show inherent variability, and as well the outcome of inspection activities. The problem is addressed under the framework of reliability based optimization. The initiation and propagation of fatigue cracks are efficiently modeled using cohesive zone elements. The applicability of the method is demonstrated by a numerical example, which involves a plate with two holes subject to alternating stress. PMID:23564979

  8. Reliability-Based Planning of Inspection, Operation and Maintenance for Offshore Oil & Gas Structures and Wind Turbines

    DEFF Research Database (Denmark)

    Sørensen, John Dalsgaard

    2011-01-01

    Reliability-based cost-optimal planning of inspection, maintenance and operation has many applications. In this paper applications for planning of inspections for oil & gas jacket structures and of operation and maintenance of offshore wind turbines are described and illustrated by examples....

  9. A reliability program for emergency diesel generators at nuclear power plants: Maintenance, surveillance, and condition monitoring

    International Nuclear Information System (INIS)

    Lofgren, E.V.; Henderson, W.; Burghardt, D.; Kripps, L.; Rothleder, B.

    1988-12-01

    This report is a companion report on NUREG/CR-5078, Volume 1, ''A Reliability Program for Emergency Diesel Generators at Nuclear Power Plants: Program Structure.'' The purpose of this report is to provide technical findings and insights related to: failure evaluation, troubleshooting, maintenance, surveillance, and condition monitoring. Examples and recommendations are provided for each of these areas based on actual emergency diesel generator (EDG) operating experience and the opinions of diesel generator experts. This report expands the more general guidance provided in Volume 1. In addition, a discussion of EDG interactions with other plant systems (e.g., instrument, air, service water, dc power) is provided since experience has shown that these support systems and their operation can adversely affect EDG reliability. Portions of this report have been designed for use by onsite personnel for evaluating operational characteristics of EDGs. 5 refs., 8 figs., 7 tabs

  10. Evaluation of reliability of on-site A.C. power systems based on maintenance records

    International Nuclear Information System (INIS)

    Basso, G.; Pia, S.; Fusari, W.; Soressi, G.; Vaccari, G.

    1986-01-01

    To the end of ascertain in what extent the evaluation of reliability of emergency diesel generators (D.G.) can be improved by means of a deeper knowledge of their operating history a study has been carried-out on 21 D.G. sets: 4 D.G. of the Caorso nuclear plant (BWR, 870 MWe) and 17 D.G. in service at 6 steam-electric fossil-fuelled plants. The major points of interest resulting from this study are: 1) reliability assessments of A.C. on-site power Systems, made on the basis of outcomes of surveillance tests, may lead to results which overestimate the real performance. 2) the unreliability of a redundant System of stand-by components is determined in large extent by unavailabilities due to scheduled and unscheduled maintenance, latent failures, tests. (authors)

  11. Evaluation of reliability of on-site A.C. power systems based on maintenance records

    Energy Technology Data Exchange (ETDEWEB)

    Basso, G.; Pia, S. [ENEA/TERM/VAOEC, C.R.E. Casaccla via Anguillarese, 00100 Roma/Rome (Italy); Fusari, W. [ENEL, Rome (Italy); Soressi, G.; Vaccari, G. [ENEL, Centro di Ricerca Termica e Nucl., Via Rubattino, 54, 1-20134 Mllano/Milan (Italy)

    1986-02-15

    To the end of ascertain in what extent the evaluation of reliability of emergency diesel generators (D.G.) can be improved by means of a deeper knowledge of their operating history a study has been carried-out on 21 D.G. sets: 4 D.G. of the Caorso nuclear plant (BWR, 870 MWe) and 17 D.G. in service at 6 steam-electric fossil-fuelled plants. The major points of interest resulting from this study are: 1) reliability assessments of A.C. on-site power Systems, made on the basis of outcomes of surveillance tests, may lead to results which overestimate the real performance. 2) the unreliability of a redundant System of stand-by components is determined in large extent by unavailabilities due to scheduled and unscheduled maintenance, latent failures, tests. (authors)

  12. A holistic framework of degradation modeling for reliability analysis and maintenance optimization of nuclear safety systems

    International Nuclear Information System (INIS)

    Lin, Yanhui

    2016-01-01

    Components of nuclear safety systems are in general highly reliable, which leads to a difficulty in modeling their degradation and failure behaviors due to the limited amount of data available. Besides, the complexity of such modeling task is increased by the fact that these systems are often subject to multiple competing degradation processes and that these can be dependent under certain circumstances, and influenced by a number of external factors (e.g. temperature, stress, mechanical shocks, etc.). In this complicated problem setting, this PhD work aims to develop a holistic framework of models and computational methods for the reliability-based analysis and maintenance optimization of nuclear safety systems taking into account the available knowledge on the systems, degradation and failure behaviors, their dependencies, the external influencing factors and the associated uncertainties.The original scientific contributions of the work are: (1) For single components, we integrate random shocks into multi-state physics models for component reliability analysis, considering general dependencies between the degradation and two types of random shocks. (2) For multi-component systems (with a limited number of components):(a) a piecewise-deterministic Markov process modeling framework is developed to treat degradation dependency in a system whose degradation processes are modeled by physics-based models and multi-state models; (b) epistemic uncertainty due to incomplete or imprecise knowledge is considered and a finite-volume scheme is extended to assess the (fuzzy) system reliability; (c) the mean absolute deviation importance measures are extended for components with multiple dependent competing degradation processes and subject to maintenance; (d) the optimal maintenance policy considering epistemic uncertainty and degradation dependency is derived by combining finite-volume scheme, differential evolution and non-dominated sorting differential evolution; (e) the

  13. Opportunistic or event-driven maintenance at the Stanford Linear Accelerator Center

    International Nuclear Information System (INIS)

    Allen, C.W.; Anderson, S.; Erickson, R.; Linebarger, W.; Sheppard, J.C.; Stanek, M.

    1997-03-01

    The Stanford Linear Accelerator Center (SLAC) uses a maintenance management philosophy that is best described as opportunistic or event-driven. Opportunistic maintenance can be defined as a systematic method of collecting, investigating, pre-planning, and publishing a set of proposed maintenance tasks and acting on them when there is an unscheduled failure or repair ''opportunity''. Opportunistic maintenance can be thought of as a modification of the run-to-fail maintenance management philosophy. This maintenance plan was adopted and developed to improve the overall availability of SLAC's linear accelerator, beam delivery systems, and associated controls, power systems, and utilities. In the late 1980's, as the technical complexity of the accelerator facility increased, variations on a conventional maintenance plan were used with mixed results. These variations typically included some type of regular periodic interruption to operations. The periodic shutdowns and unscheduled failures were additive and resulted in unsatisfactory availability. Maintenance issues are evaluated in a daily meeting that includes the accelerator managers, maintenance supervisors and managers, safety office personnel, program managers, and accelerator operators. Lists of pending maintenance tasks are made available to the general SLAC population by a World Wide Web site on a local internet. A conventional information system which pre-dates the WWW site is still being used to provide paper copies to groups that are not yet integrated into the WWW system. The local internet provides real time maintenance information, allowing people throughout the facility to track progress on tasks with essentially real-time status updates. With the introduction of opportunistic maintenance, the accelerator's availability has been measurably better. This paper will discuss processes, rolls and responsibilities of key maintenance groups, and management tools developed to support opportunistic maintenance

  14. Improving motor reliability in nuclear power plants: Volume 1, Performance evaluation and maintenance practices

    International Nuclear Information System (INIS)

    Subudhi, M.; Gunther, W.E.; Taylor, J.H.; Sugarman, A.C.; Sheets, M.W.

    1987-11-01

    This report constitutes the first of the three volumes under this NUREG. The report presents recommendations for developing a cost-effective program for performance evaluation and maintenance of electric motors in nuclear power plants. These recommendations are based on current industry practices, available techniques for monitoring degradation in motor components, manufacturer's recommendations, operating experience, and results from two laboratory tests on aged motors. Two laboratory test reports on a small and a large motor are presented in separate volumes of this NUREG. These provide the basis for the various functional indicators recommended for maintenance programs in this report. The overall preventive maintenance program is separated into two broad areas of activity aimed at mitigating the potential effects of equipment aging: Performance Evaluation and Equipment Maintenance. The latter involves actually maintaining the condition of the equipment while the former involves those activities undertaken to monitor degradation due to aging. These monitoring methods are further categorized into periodic testing, surveillance testing, continuous monitoring and inspections. This study focuses on the methods and procedures for performing the above activities to maintain the motors operationally ready in a nuclear facility. This includes an assessment of various functional indicators to determine their suitability for trending to monitor motor component condition. The intrusiveness of test methods and the present state-of-the-art for using the test equipment in a plant environment are discussed. In conclusion, implementation of the information provided in this report, will improve motor reliability in nuclear power plants. The study indicates the kinds of tests to conduct, how and when to conduct them, and to which motors the tests should be applied. 44 refs., 12 figs., 13 tabs

  15. Optimizing preventive maintenance with maintenance templates

    International Nuclear Information System (INIS)

    Dozier, I.J.

    1996-01-01

    Rising operating costs has caused maintenance professionals to rethink their strategy for preventive maintenance (PM) programs. Maintenance Templates are pre-engineered PM task recommendations for a component type based on application of the component. Development of the maintenance template considers the dominant failure cause of the component and the type of preventive maintenance that can predict or prevent the failure from occurring. Maintenance template development also attempts to replace fixed frequency tasks with condition monitoring tasks such as vibration analysis or thermography. For those components that have fixed frequency PM intervals, consideration is given to the maintenance drivers such as criticality, environment and usage. This helps to maximize the PM frequency intervals and maximize the component availability. Maintenance Templates have been used at PECO Energy's Limerick Generating Station during the Reliability Centered Maintenance (RCM) Process to optimize their PM program. This paper describes the development and uses of the maintenance templates

  16. Maintenance cost control at the Pacific Missile Test Center.

    OpenAIRE

    Jenson, Richard J.

    1980-01-01

    Approved for public release; distribution is unlimited The Pacific Missile Test Center (PMTC) is the Navy's largest Major Range and Test Facility Base, with an investment of over one billion dollars. The majority of this investment is in range test equipment and facilities including radar, telemetry, communication and command/ control systems. Concern is growing over the "excessively obsolete condition of PMTC technical equipment." Improvement of factors concerned with...

  17. A study on maintenance reliability allocation of urban transit brake system using hybrid neuro-genetic technique

    International Nuclear Information System (INIS)

    Bae, Chul Ho; Kim, Hyun Jun; Lee, Jung Hwan; Suh, Myung Won; Chu, Yul

    2007-01-01

    For reasonable establishing of maintenance strategies, safety security and cost limitation must be considered at the same time. In this paper, the concept of system reliability introduces and optimizes as the key of reasonable maintenance strategies. This study aims at optimizing component's reliability that satisfies the target reliability of brake system in the urban transit. First of all, constructed reliability evaluation system is used to predict and analyze reliability. This data is used for the optimization. To identify component reliability in a system, a method is presented in this paper which uses hybrid neuro-genetic technique. Feed-forward multi-layer neural networks trained by back propagation are used to find out the relationship between component reliability (input) and system reliability (output) of a structural system. The inverse problem can be formulated by using neural network. Genetic algorithm is used to find the minimum square error. Finally, this paper presents reasonable maintenance cycle of urban transit brake system by using optimal system reliability

  18. Job analysis of the electrician position for the nuclear power plant maintenance personnel reliability model

    International Nuclear Information System (INIS)

    Federman, P.J.; Bartter, W.D.; Siegel, A.I.

    1984-02-01

    This report presents the methods, procedures, and results of the fourth and final of a series of job analytic studies which characterize maintenance positions in nuclear power plants. The electrician position is the subject of the present report. The characterization of the electrician position takes the form of detailed information about: (1) the frequency of performing various tasks, (2) the time required for performing each task, (3) the training required for adequate performance of each task, and (4) the perceived consequences resulting from inadequate task performance. Additionally, information is presented about the intellective and the perceptual-motor loading imposed by each task. This information contributes to job design and training requirements derivation as well as to the assessment of human performance reliability in nuclear power plants

  19. Economic evaluation of reliability-centred maintenance (RCM): an electricity transmission industry perspective

    International Nuclear Information System (INIS)

    Bowler, D.J.; Primrose, P.L.; Leonard, R.

    1995-01-01

    Traditional approaches to appraising the introduction of reliability centred maintenance (RCM) are shown to exhibit severe limitations. In particular, the economic implications surrounding its adoption are repeatedly mis-stated, with the consequence that organisations may be investing in unprofitable RCM ventures. Previously quoted benefits are examined and, contrary to established opinion, it is shown that these 'generalised' statements, once redeemed, are able to be quantified. The paper then proceeds to describe a financial methodology, developed by NGC and UMIST, by which the introduction of RCM can be evaluated. Moreover, it shows that, by regarding RCM as an investment decision, rather than an 'act of faith', the economic viability of a potential application can be determined before vital resources are committed. Finally, it is demonstrated that when the methodology is applied within the context of the electricity transmission industry, the economic case underlying the adoption of RCM can be realistically appraised. (author)

  20. Reliability of the grid as function of power flow and configuration during maintenance

    International Nuclear Information System (INIS)

    Kovacs, Z.; Hlavac, P.; Janicek, F.

    2012-01-01

    The paper describes using of PSA (Probabilistic Safety Assessment) for analysis of the partial and total blackout of the grid for different power flows and configuration of the grid given by the preventive maintenance activities. The method uses event and fault tree analysis in combination with the dynamic stability analysis of the grid. The event trees model the grid response to the initiating event of the accident. The fault trees are used to model the reliability of the substation protection systems. Different end states of the event trees are simulated on the basis of dynamic stability analysis, as safe and emergency state, partial and total blackout. Minimal cut sets are generated, importance measures (Fussel-Vesely importance, risk increase factor and risk decrease factors) are calculated for the total and partial blackout. The most dominant initiating events and component failures are identified from the risk point of view. Using the PSA the model, of the transmission grid is being developed. The model can be implemented into the risk monitor software to analyze the risk for different configurations of the grid and to support the operation and the maintenance activities. (Authors)

  1. The maintenance training center of the paks nuclear power plant - past, present and future

    International Nuclear Information System (INIS)

    Kiss, I.

    2001-01-01

    The safety of the Paks nuclear power plant (Paks NPP) is a political-economic factor with general influence on the stability of the Hungarian economy. Since the beginning of the 1990s, the plant management has been taking significant efforts to learn about the factors that define plant safety and to reveal areas where safety can be further improved. Major emphasis is also placed on the provision of resources and creation of conditions necessary for the preservation of staff competence. In 1997 a separate, maintenance-specific facility was erected. The Maintenance Training Center of the Paks NPP is a worldwide major unique center. (orig.) [de

  2. 20 CFR 670.220 - Are we responsible for the protection and maintenance of center facilities?

    Science.gov (United States)

    2010-04-01

    ... 20 Employees' Benefits 3 2010-04-01 2010-04-01 false Are we responsible for the protection and maintenance of center facilities? 670.220 Section 670.220 Employees' Benefits EMPLOYMENT AND TRAINING ADMINISTRATION, DEPARTMENT OF LABOR THE JOB CORPS UNDER TITLE I OF THE WORKFORCE INVESTMENT ACT Site Selection...

  3. On the optimal scheduling of periodic tests and maintenance for reliable redundant components

    International Nuclear Information System (INIS)

    Courtois, Pierre-Jacques; Delsarte, Philippe

    2006-01-01

    Periodically, some m of the n redundant components of a dependable system may have to be taken out of service for inspection, testing or preventive maintenance. The system is then constrained to operate with lower (n-m) redundancy and thus with less reliability during these periods. However, more frequent periodic inspections decrease the probability that a component fail undetected in the time interval between successive inspections. An optimal time schedule of periodic preventive operations arises from these two conflicting factors, balancing the loss of redundancy during inspections against the reliability benefits of more frequent inspections. Considering no other factor than this decreased redundancy at inspection time, this paper demonstrates the existence of an optimal interval between inspections, which maximizes the mean time between system failures. By suitable transformations and variable identifications, an analytic closed form expression of the optimum is obtained for the general (m, n) case. The optimum is shown to be unique within the ranges of parameter values valid in practice; its expression is easy to evaluate and shown to be useful to analyze and understand the influence of these parameters. Inspections are assumed to be perfect, i.e. they cause no component failure by themselves and leave no failure undetected. In this sense, the optimum determines a lowest bound for the system failure rate that can be achieved by a system of n-redundant components, m of which require for inspection or maintenance recurrent periods of unavailability of length t. The model and its general closed form solution are believed to be new . Previous work had computed optimal values for an estimation of a time average of system unavailability, but by numerical procedures only and with different numerical approximations, other objectives and model assumptions (one component only inspected at a time), and taking into account failures caused by testing itself, repair and

  4. Methods for Calculating Frequency of Maintenance of Complex Information Security System Based on Dynamics of Its Reliability

    Science.gov (United States)

    Varlataya, S. K.; Evdokimov, V. E.; Urzov, A. Y.

    2017-11-01

    This article describes a process of calculating a certain complex information security system (CISS) reliability using the example of the technospheric security management model as well as ability to determine the frequency of its maintenance using the system reliability parameter which allows one to assess man-made risks and to forecast natural and man-made emergencies. The relevance of this article is explained by the fact the CISS reliability is closely related to information security (IS) risks. Since reliability (or resiliency) is a probabilistic characteristic of the system showing the possibility of its failure (and as a consequence - threats to the protected information assets emergence), it is seen as a component of the overall IS risk in the system. As it is known, there is a certain acceptable level of IS risk assigned by experts for a particular information system; in case of reliability being a risk-forming factor maintaining an acceptable risk level should be carried out by the routine analysis of the condition of CISS and its elements and their timely service. The article presents a reliability parameter calculation for the CISS with a mixed type of element connection, a formula of the dynamics of such system reliability is written. The chart of CISS reliability change is a S-shaped curve which can be divided into 3 periods: almost invariable high level of reliability, uniform reliability reduction, almost invariable low level of reliability. Setting the minimum acceptable level of reliability, the graph (or formula) can be used to determine the period of time during which the system would meet requirements. Ideally, this period should not be longer than the first period of the graph. Thus, the proposed method of calculating the CISS maintenance frequency helps to solve a voluminous and critical task of the information assets risk management.

  5. Reliability centred maintenance of the cathodic protection system of the Bolivia-Brazil gas pipeline

    Energy Technology Data Exchange (ETDEWEB)

    Coelho, Jorge Fernando Pereira [Transportadora Brasileira Gasoduto, TBG, Bolivia-Brasil S.A (Brazil)

    2004-07-01

    This paper presents the results of the Reliability-Centred Maintenance study performed on the Cathodic Protection System of the Bolivia -Brazil Gas Pipeline. The Cathodic Protection installation for the north spread (from Corumba to Guararema, 1413 km) was commissioned in March 1999 and for the south spread (from Campinas to Porto Alegre, 1180 km) one year after. The protection against corrosion of the buried external surface of our gas pipeline is provided, primarily, by an high-efficient external coating, complemented by a impressed current cathodic protection system consisting of: - Forty-one rectifiers and respective anodes ground beds; - One solar panel and respective anodes ground beds; - Fifty-nine insulating joints and respective protective devices; - Nine hundred and ninety pipe-to-soil test stations; - Thirty-six pipe-to-soil remote monitoring devices; - Forty-one electrical power feeder network to the rectifiers. The rectifiers/anodes ground beds are installed at each 50 km approximately, including the solar panel, and the pipe-to-soil test stations at each 2.5 km, under different environment conditions. The insulating joints and theirs protective devices are installed inside stations (launch and receive scrapers, compression and metering) and city-gates, as well, the pipe-to-soil remote monitoring devices. The cathodic protection system and electrical power feeder network are inspected and maintained by a TBG third part Contractor.

  6. The nuclear power plant maintenance personnel reliability prediction (NPP/MPRP) effort at Oak Ridge National Laboratory

    International Nuclear Information System (INIS)

    Knee, H.E.; Haas, P.M.; Siegel, A.I.

    1982-01-01

    Human errors committed during maintenance activities are potentially a major contribution to the overall risk associated with the operation of a nuclear power plant (NPP). An NRC-sponsored program at Oak Ridge National Laboratory is attempting to develop a quantitative predictive technique to evaluate the contribution of maintenance errors to the overall NPP risk. The current work includes a survey of the requirements of potential users to ascertain the need for and content of the proposed quantitative model, plus an initial job/task analysis to determine the scope and applicability of various maintenance tasks. In addition, existing human reliability prediction models are being reviewed and assessed with respect to their applicability to NPP maintenance tasks. This paper discusses the status of the program and summarizes the results to date

  7. Human Reliability Analysis. Applicability of the HRA-concept in maintenance shutdown

    International Nuclear Information System (INIS)

    Obenius, Aino

    2007-08-01

    Probabilistic Safety Analysis (PSA) is performed for Swedish nuclear power plants in order to make predictions and improvements of system safety. The analysis of the Three Mile Island and Chernobyl accidents contributed to broaden the approach to nuclear power plant safety. A system perspective focusing on the interaction between aspects of Man, Technology and Organization (MTO) emerged in addition to the development of Human Factors knowledge. To take the human influence on the technical system into consideration when performing PSAs, a Human Reliability Analysis (HRA) is performed. PSA is performed for different stages and plant operating states, and the current state of Swedish analyses is Low power and Shutdown (LPSD), also called Shutdown PSA (SPSA). The purpose of this master's thesis is to describe methods and basic models used when analysing human reliability for the LPSD state. The following questions are at issue: 1. How can the LPSD state be characterised and defined? 2. What is important to take into consideration when performing a LPSD HRA? 3. How can human behaviour be modelled for a LPSD risk analysis? 4. According to available empirical material, how are the questions above treated in performed analysis of human operation during LPSD? 5. How does the result of the questions above affect the way methods for analysis of LPSD could and/or should be developed? The procedure of this project has mainly consisted of literature studies of available theory for modelling of human behaviour and risk analysis of the LPSD state. This study regards analysis of planned outages when maintenance, fuel change, tests and inspections are performed. The outage period is characterised by planned maintenance activities performed in rotating 3-shifts, around the clock, as well as many of the persons performing work tasks on the plant being external contractors. The working conditions are characterised by stress due to heat, radiation and physically demanding or monotonous

  8. 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.

  9. Performance-based maintenance of gas turbines for reliable control of degraded power systems

    Science.gov (United States)

    Mo, Huadong; Sansavini, Giovanni; Xie, Min

    2018-03-01

    Maintenance actions are necessary for ensuring proper operations of control systems under component degradation. However, current condition-based maintenance (CBM) models based on component health indices are not suitable for degraded control systems. Indeed, failures of control systems are only determined by the controller outputs, and the feedback mechanism compensates the control performance loss caused by the component deterioration. Thus, control systems may still operate normally even if the component health indices exceed failure thresholds. This work investigates the CBM model of control systems and employs the reduced control performance as a direct degradation measure for deciding maintenance activities. The reduced control performance depends on the underlying component degradation modelled as a Wiener process and the feedback mechanism. To this aim, the controller features are quantified by developing a dynamic and stochastic control block diagram-based simulation model, consisting of the degraded components and the control mechanism. At each inspection, the system receives a maintenance action if the control performance deterioration exceeds its preventive-maintenance or failure thresholds. Inspired by realistic cases, the component degradation model considers random start time and unit-to-unit variability. The cost analysis of maintenance model is conducted via Monte Carlo simulation. Optimal maintenance strategies are investigated to minimize the expected maintenance costs, which is a direct consequence of the control performance. The proposed framework is able to design preventive maintenance actions on a gas power plant, to ensuring required load frequency control performance against a sudden load increase. The optimization results identify the trade-off between system downtime and maintenance costs as a function of preventive maintenance thresholds and inspection frequency. Finally, the control performance-based maintenance model can reduce

  10. Effect of amplifier component maintenance on laser system availability and reliability for the US National Ignition Facility

    International Nuclear Information System (INIS)

    Erlandson, A.C.; Lambert, H.; Zapata, L.E.

    1996-12-01

    We have analyzed the availability and reliability of the flashlamp-pumped, Nd:glass amplifiers that, as a part of a laser now being designed for future experiments, in inertial confinement fusion (ICF), will be used in the National Ignition Facility (NIF). Clearly , in order for large ICF systems such as the NIF to operate effectively as a whole, all components must meet demanding availability and reliability requirements. Accordingly, the NIF amplifiers can achieve high reliability and availability by using reliable parts, and by using a cassette-based maintenance design that allows most key amplifier parts to be 1744 replaced within a few hours. In this way, parts that degrade slowly, as the laser slabs, silver reflectors, and blastshields can be expected to do, based on previous experience, can be replaced either between shots or during scheduled maintenance periods, with no effect on availability or reliability. In contrast, parts that fail rapidly, such as the flashlamps, can and do cause unavailability or unreliability. Our analysis demonstrates that the amplifiers for the NIF will meet availability and reliability goals, respectively, of 99.8% and 99.4%, provided that the 7680 NIF flashlamps in NIF have failure rates of less than, or equal to, those experienced on Nova, a 5000-lamp laser at Lawrence Livermore National Laboratory (LLNL)

  11. Penerapan Preventive Maintenance Untuk Meningkatkan Reliability Pada Boiler Feed Pump PLTU Tarahan Unit 3 & 4

    OpenAIRE

    Saputra, Melki

    2015-01-01

    Pemeliharaan dan perawatan merupakan kegiatan untuk menjamin mesin dapat bekerja sebagaimana mestinya. Pemeliharaan dan perawatan menyeluruh untuk meningkatkan produktivitas perusahaan dikenal dengan Preventive Maintenance. pemeliharaan keterlibatan operator melalui kegiatan autonomous maintenance. PT. PLN (Persero) Pembangkitan Sumatera Bagian Selatan Sektor Tarahan merupakan salah satu perusahaan penghasil listrik dan semua mesinnya beroperasi selama 24 jam. Beroperasinya mesin secara c...

  12. Application of genetic algorithms to the maintenance scheduling optimization in a nuclear system basing on reliability

    International Nuclear Information System (INIS)

    Lapa, Celso M. Franklin; Pereira, Claudio M.N.A.; Mol, Antonio C. de Abreu

    1999-01-01

    This paper presents a solution based on genetic algorithm and probabilistic safety analysis that can be applied in the optimization of the preventive maintenance politic of nuclear power plant safety systems. The goal of this approach is to improve the average availability of the system through the optimization of the preventive maintenance scheduling politic. The auxiliary feed water system of a two loops pressurized water reactor is used as a sample case, in order to demonstrate the effectiveness of the proposed method. The results, when compared to those obtained by some standard maintenance politics, reveal quantitative gains and operational safety levels. (author)

  13. Job analysis of the maintenance supervisor and instrument and control supervisor positions for the nuclear power plant maintenance personnel reliability model

    International Nuclear Information System (INIS)

    Bartter, W.D.; Siegel, A.I.; Federman, P.J.

    1982-11-01

    The present report presents the results of an analysis of the jobs of maintenance mechanic supervisors and instrument and control technician supervisors in nuclear power plants. Such an analysis was considered to be a necessary step in defining the scope and focus of a model for predicting and analyzing nuclear power maintenance reliability. The model will focus upon tasks and subtasks performed by various job positions. The results of this job analysis, along with the results of a survey of user needs vis-a-vis such a model and the results of parallel analyses of the job of maintenance mechanics and of instrument and control technicians provide the sound foundation on which such a model may be built. Job analysis possesses implications for a number of purposes. It provides insight into selection standards, job structuring and organization, performance analysis, training objective establishment, and training content derivation. Accordingly, the results of the present work possess implications for a variety of interest areas relative to safe and efficient operation of nuclear power plants

  14. The Maintenance Personnel Performance Simulation (MAPPS) model: A human reliability analysis tool

    International Nuclear Information System (INIS)

    Knee, H.E.

    1985-01-01

    The Maintenance Personnel Performance Simulation (MAPPS) model is a computerized, stochastic, task-oriented human behavioral model developed to provide estimates of nuclear power plant (NPP) maintenance team performance measures. It is capable of addressing person-machine, person-environment, and person-person relationships, and accounts for interdependencies that exist between the subelements that make up the maintenance task of interest. The primary measures of performance estimated by MAPPS are: 1) the probability of successfully completing the task of interest and 2) the task duration time. MAPPS also estimates a host of other performance indices, including the probability of an undetected error, identification of the most- and least-likely error-prone subelements, and maintenance team stress profiles during task execution

  15. Preventative Maintenance and Reliability Study for the Central Heating and Power Plant at Fort Wainwright, Alaska

    National Research Council Canada - National Science Library

    Vavrin, John L; Brown, III, William T; Kemme, Michael R; Westerman, John; Lorand, Robert T; Walden, Charles; Swinehart, Curtis

    2007-01-01

    ... (FWA) (Vavrin et al. 2006) recommended that if the option for a new CHPP were to be pursued, among the tasks suggested for further analysis was to determine predictive maintenance requirements and new technologies for the existing plant...

  16. Preventive Maintenance and Reliability Study for the Central Heating and Power Plant at Fort Wainwright, Alaska

    National Research Council Canada - National Science Library

    Vavrin, John L; Brown, III, William T; Kemme, Michael R; Westerman, John; Lorand, Robert; Walden, Charles; Swinehart, Curtis

    2007-01-01

    ... (FWA) (Vavrin et al. 2006) recommended that if the option for a new CHPP were to be pursued, among the tasks suggested for further analysis was to determine predictive maintenance requirements and new technologies for the existing plant...

  17. Design of equipment safety & reliability for an aseptic liquid food packaging line through maintenance engineering

    OpenAIRE

    Riccetti, Sauro

    2011-01-01

    This thesis was submitted for the degree of Doctor of Philosophy and awarded by Brunel University. The organisation of maintenance, in the Aseptic Liquid Food (ALF) industry, represents an important management task that enables a company to pursue higher manufacturing effectiveness and improved market share. This research is concerned with the process to design and implement maintenance tasks. These two complementary processes (design and implementation) have been thought and designed to a...

  18. Design of fuel cell powered data centers for sufficient reliability and availability

    Science.gov (United States)

    Ritchie, Alexa J.; Brouwer, Jacob

    2018-04-01

    It is challenging to design a sufficiently reliable fuel cell electrical system for use in data centers, which require 99.9999% uptime. Such a system could lower emissions and increase data center efficiency, but the reliability and availability of such a system must be analyzed and understood. Currently, extensive backup equipment is used to ensure electricity availability. The proposed design alternative uses multiple fuel cell systems each supporting a small number of servers to eliminate backup power equipment provided the fuel cell design has sufficient reliability and availability. Potential system designs are explored for the entire data center and for individual fuel cells. Reliability block diagram analysis of the fuel cell systems was accomplished to understand the reliability of the systems without repair or redundant technologies. From this analysis, it was apparent that redundant components would be necessary. A program was written in MATLAB to show that the desired system reliability could be achieved by a combination of parallel components, regardless of the number of additional components needed. Having shown that the desired reliability was achievable through some combination of components, a dynamic programming analysis was undertaken to assess the ideal allocation of parallel components.

  19. Reliability Evaluation of Machine Center Components Based on Cascading Failure Analysis

    Science.gov (United States)

    Zhang, Ying-Zhi; Liu, Jin-Tong; Shen, Gui-Xiang; Long, Zhe; Sun, Shu-Guang

    2017-07-01

    In order to rectify the problems that the component reliability model exhibits deviation, and the evaluation result is low due to the overlook of failure propagation in traditional reliability evaluation of machine center components, a new reliability evaluation method based on cascading failure analysis and the failure influenced degree assessment is proposed. A direct graph model of cascading failure among components is established according to cascading failure mechanism analysis and graph theory. The failure influenced degrees of the system components are assessed by the adjacency matrix and its transposition, combined with the Pagerank algorithm. Based on the comprehensive failure probability function and total probability formula, the inherent failure probability function is determined to realize the reliability evaluation of the system components. Finally, the method is applied to a machine center, it shows the following: 1) The reliability evaluation values of the proposed method are at least 2.5% higher than those of the traditional method; 2) The difference between the comprehensive and inherent reliability of the system component presents a positive correlation with the failure influenced degree of the system component, which provides a theoretical basis for reliability allocation of machine center system.

  20. [STRATEGY OF USE AND MAINTENANCE OF CLINICAL HOSPITAL CENTER RIJEKA IN ACCORDANCE WITH KEY PERFORMANCE INDICATORS FOR STRATEGIC HEALTHCARE FACILITIES MAINTENANCE].

    Science.gov (United States)

    Sjekavica, Mariela; Haller, Herman; Cerić, Anita

    2015-01-01

    Building usage is the phase in the building life cycle that is most time-consuming, most functional, most significant due to building purpose and often systematically ignored. Maintenance is the set of activities that ensure the planned duration of facility exploitation phase in accordance with the requirements for quality maintenance of a large number of important building features as well as other elements immanent to the nature of facilities' life. The aim of the study is to show the analysis of the current state of organized, planned and comprehensive managerial approach in hospital utilization and maintenance in the Republic of Croatia, given on the case study of Clinical hospital center in Rijeka. The methodology used consists of relevant literature section of theory of facility utilization, maintenance and management in general, hospital buildings especially, display of practice on case study, and comparison of key performance indicators values obtained through interview with those that author Igal M. Shohet defined in his study by field surveys and statistical analyses. Despite many positive indicators of Clinical hospital center Rijeka maintenance, an additional research is needed in order to define a more complete national hospital maintenance strategy.

  1. Evaluation of Sociodemographic Determinants in Narcotic Users Referring to Center for Methadone Maintenance Therapy of Yazd, Iran

    Directory of Open Access Journals (Sweden)

    M.H. Lotfi

    2012-07-01

    Full Text Available Introduction: Addiction is a habit or behavior that is often hard to quit. It is estimated that 190 million persons are substance users around the world. Substance abuse creates tolerance after a while. Shortly after taking the drug, a person will not enjoy as the beginning of its use; that is why the amount of substance used is gradually increased. The purpose of this study was to find the reasons of tendency to narcotics among addicted individuals referred to methadone maintenance therapy (MMT center in Yazd. Materials & Methods: This study was a descriptive-analytic study on 100 addicts referred to methadone maintenance treatment center (MMT in Yazd. Data was collected by a pre-designed questionnaire with acceptable validity and reliability. Data was analyzed using SPSS statistical software and employing descriptive statistics such as percentage, ratio, mean, standard deviation and statistical tests such as t-test and chi- square was performed. Results: 41.9 % of addicts were unemployed, 4.77% married and 5.64% had elementary education. The most common method of substance consumption was inhalation (2.40%. Heroin was the most frequent type of substance used (1/51% The relationship between marital status and type of substance used, and age of onset of drug use was significant. The frequency of substance consumption was significantly different regarding the history of drug use in father, brother and spouses of patients in both sexes. Conclusion: Results of the current study showed that subjects at an early age (adolescence and early adulthood, individuals with low educational status, those with unstable jobs and low income, presence of addicted individuals among first-degree relatives can be the causes leading to addiction in the community.

  2. 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

  3. Maintenance Personnel Performance Simulation (MAPPS) model: a human reliability analysis tool

    International Nuclear Information System (INIS)

    Knee, H.E.

    1985-01-01

    The Maintenance Personnel Performance Simulation (MAPPS) model is a computerized, stochastic, task-oriented human behavioral model developed to provide estimates of nuclear power plant (NPP) maintenance team performance measures. It is capable of addressing person-machine, person-environment, and person-person relationships, and accounts for interdependencies that exist between the subelements that make up the maintenance task of interest. The primary measures of performance estimated by MAPPS are: (1) the probability of successfully completing the task of interest; and (2) the task duration time. MAPPS also estimates a host of other performance indices, including the probability of an undetected error, identification of the most- and least-likely error-prone subelements, and maintenance team stress profiles during task execution. The MAPPS model was subjected to a number of evaluation efforts that focused upon its practicality, acceptability, usefulness, and validity. Methods used for these efforts included a case method approach, consensus estimation, and comparison with observed task performance measures at a NPP. Favorable results, such as close agreement between task duration times for two tasks observed in the field (67.0 and 119.8 minutes, respectively), and estimates by MAPPS (72.0 and 124.0 minutes, respectively) enhance the confidence in the future use of MAPPS. 8 refs., 1 fig

  4. 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

  5. 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

  6. Job analysis of the instrument and control technician position for the nuclear power plant maintenance personnel reliability model

    International Nuclear Information System (INIS)

    Siegel, A.I.; Bartter, W.D.; Federman, P.J.

    1983-08-01

    This report is one of a series that is planned to describe the results of a program undertaken by the Oak Ridge National Laboratory (ORNL) for the US Nuclear Regulatory Commission, Office of Nuclear Regulatory Research, to define, develop, validate, and disseminate a methodology for the quantitative prediction of human reliability in the conduct of maintenance tasks in nuclear power plants (NPPs). ORNL has subcontracted portions of this effort to Applied Psychological Services, Inc. This report on the job analysis of the Instrument and Control technician (NUREG/CR-3274) and a report on the job analysis of the electrician position (NUREG/CR-3275) comprise a part of the initial efforts of the development phase of this program. With the publication of the job analysis of the electrician position, the series of job analyses reports addressing nuclear power plant maintenance personnel will be complete. Subsequent reports addressing model development and validation are planned

  7. Initiating statistical maintenance optimization

    International Nuclear Information System (INIS)

    Doyle, E. Kevin; Tuomi, Vesa; Rowley, Ian

    2007-01-01

    Since the 1980 s maintenance optimization has been centered around various formulations of Reliability Centered Maintenance (RCM). Several such optimization techniques have been implemented at the Bruce Nuclear Station. Further cost refinement of the Station preventive maintenance strategy includes evaluation of statistical optimization techniques. A review of successful pilot efforts in this direction is provided as well as initial work with graphical analysis. The present situation reguarding data sourcing, the principle impediment to use of stochastic methods in previous years, is discussed. The use of Crowe/AMSAA (Army Materials Systems Analysis Activity) plots is demonstrated from the point of view of justifying expenditures in optimization efforts. (author)

  8. Efficiency evaluation of an electronic equipment: availability,reliability and maintenance; Notion d'efficacite d'un equipement electronique: disponibilite, fiabilite et maintenabilite

    Energy Technology Data Exchange (ETDEWEB)

    Guyot, C

    1966-07-01

    This concept of efficiency often called ''system effectiveness'', is presented and analyzed in terms of reliability and maintenance. It allows to define the availability factor of an electronic equipment. A procedure of evaluation is proposed. (A.L.B.)

  9. Technology development of maintenance optimization and reliability analysis for safety features in nuclear power plants

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Tae Woon; Choi, Seong Soo; Lee, Dong Gue; Kim, Young Il

    1999-12-01

    The reliability data management system (RDMS) for safety systems of PHWR type plants has been developed and utilized in the reliability analysis of the special safety systems of Wolsong Unit 1,2 with plant overhaul period lengthened. The RDMS is developed for the periodic efficient reliability analysis of the safety systems of Wolsong Unit 1,2. In addition, this system provides the function of analyzing the effects on safety system unavailability if the test period of a test procedure changes as well as the function of optimizing the test periods of safety-related test procedures. The RDMS can be utilized in handling the requests of the regulatory institute actively with regard to the reliability validation of safety systems. (author)

  10. Integrated Reliability Estimation of a Nuclear Maintenance Robot including a Software

    Energy Technology Data Exchange (ETDEWEB)

    Eom, Heung Seop; Kim, Jae Hee; Jeong, Kyung Min [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2011-10-15

    Conventional reliability estimation techniques such as Fault Tree Analysis (FTA), Reliability Block Diagram (RBD), Markov Model, and Event Tree Analysis (ETA) have been used widely and approved in some industries. Then there are some limitations when we use them for a complicate robot systems including software such as intelligent reactor inspection robots. Therefore an expert's judgment plays an important role in estimating the reliability of a complicate system in practice, because experts can deal with diverse evidence related to the reliability and then perform an inference based on them. The proposed method in this paper combines qualitative and quantitative evidences and performs an inference like experts. Furthermore, it does the work in a formal and in a quantitative way unlike human experts, by the benefits of Bayesian Nets (BNs)

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

    Science.gov (United States)

    2012-08-15

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

  12. Multiple Shh signaling centers participate in fungiform papilla and taste bud formation and maintenance.

    Science.gov (United States)

    Liu, Hong Xiang; Ermilov, Alexandre; Grachtchouk, Marina; Li, Libo; Gumucio, Deborah L; Dlugosz, Andrzej A; Mistretta, Charalotte M

    2013-10-01

    The adult fungiform taste papilla is a complex of specialized cell types residing in the stratified squamous tongue epithelium. This unique sensory organ includes taste buds, papilla epithelium and lateral walls that extend into underlying connective tissue to surround a core of lamina propria cells. Fungiform papillae must contain long-lived, sustaining or stem cells and short-lived, maintaining or transit amplifying cells that support the papilla and specialized taste buds. Shh signaling has established roles in supporting fungiform induction, development and patterning. However, for a full understanding of how Shh transduced signals act in tongue, papilla and taste bud formation and maintenance, it is necessary to know where and when the Shh ligand and pathway components are positioned. We used immunostaining, in situ hybridization and mouse reporter strains for Shh, Ptch1, Gli1 and Gli2-expression and proliferation markers to identify cells that participate in hedgehog signaling. Whereas there is a progressive restriction in location of Shh ligand-expressing cells, from placode and apical papilla cells to taste bud cells only, a surrounding population of Ptch1 and Gli1 responding cells is maintained in signaling centers throughout papilla and taste bud development and differentiation. The Shh signaling targets are in regions of active cell proliferation. Using genetic-inducible lineage tracing for Gli1-expression, we found that Shh-responding cells contribute not only to maintenance of filiform and fungiform papillae, but also to taste buds. A requirement for normal Shh signaling in fungiform papilla, taste bud and filiform papilla maintenance was shown by Gli2 constitutive activation. We identified proliferation niches where Shh signaling is active and suggest that epithelial and mesenchymal compartments harbor potential stem and/or progenitor cell zones. In all, we report a set of hedgehog signaling centers that regulate development and maintenance of taste

  13. Estimating the Reliability of Aggregated and Within-Person Centered Scores in Ecological Momentary Assessment

    Science.gov (United States)

    Huang, Po-Hsien; Weng, Li-Jen

    2012-01-01

    A procedure for estimating the reliability of test scores in the context of ecological momentary assessment (EMA) was proposed to take into account the characteristics of EMA measures. Two commonly used test scores in EMA were considered: the aggregated score (AGGS) and the within-person centered score (WPCS). Conceptually, AGGS and WPCS represent…

  14. 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.

  15. 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.

  16. Reliability, availability and maintenance aspects of large-scale offshore wind farms, a concepts study

    NARCIS (Netherlands)

    Van Bussel, G.J.W.; Zaayer, M.B.

    2001-01-01

    The DOWEC projects aims at implementation of large wind turbines in large scale wind farms. part of the DOWEC project a concepts study was performed regarding the achievable reliability and availability levels. A reduction with a factor of 2 with regard to the present state of the art seems fairly

  17. A Reliable, Non-Invasive Approach to Data Center Monitoring and Management

    Directory of Open Access Journals (Sweden)

    Moises Levy

    2017-08-01

    Full Text Available Recent standards, legislation, and best practices point to data center infrastructure management systems to control and monitor data center performance. This work presents an innovative approach to address some of the challenges that currently hinder data center management. It explains how monitoring and management systems should be envisioned and implemented. Key parameters associated with data center infrastructure and information technology equipment can be monitored in real-time across an entire facility using low-cost, low-power wireless sensors. Given the data centers’ mission critical nature, the system must be reliable and deployable through a non-invasive process. The need for the monitoring system is also presented through a feedback control systems perspective, which allows higher levels of automation. The data center monitoring and management system enables data gathering, analysis, and decision-making to improve performance, and to enhance asset utilization.

  18. 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.

  19. 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)

  20. A Study on User-Centered Approach to Design an Augmented Reality Maintenance Support System in Nuclear Power Plant

    International Nuclear Information System (INIS)

    Koo, Jwa Jin; Seong, Poong Hyun

    2007-01-01

    In nuclear power plants (NPPs), as the plants become more reliable and complex, their inspection, maintenance and repair become increasingly challenging problems, and this requires many well experienced and well trained maintenance crew. On the other hands, reduction of life cycle costs of the plants is strongly required, and many crews are required to take charge of various kinds of devices, including their unfamiliar ones. Their task must be done under the strong time pressure of rigid maintenance schedule. This may cause human errors even by even the well experienced crews. Maintenance processes are both very important to guarantee quality for safety and often quite cumbersome. In the case of nuclear power plants, such processes usually demand access to documentation such as technical manuals, either in traditional paper form or electronic form. This is especially important where and when the procedures are performed infrequently. These considerations lead to considering Augmented Reality (AR) systems as an alternative to paper-based systems

  1. Reliability Analysis and Optimal Release Problem Considering Maintenance Time of Software Components for an Embedded OSS Porting Phase

    Science.gov (United States)

    Tamura, Yoshinobu; Yamada, Shigeru

    OSS (open source software) systems which serve as key components of critical infrastructures in our social life are still ever-expanding now. Especially, embedded OSS systems have been gaining a lot of attention in the embedded system area, i.e., Android, BusyBox, TRON, etc. However, the poor handling of quality problem and customer support prohibit the progress of embedded OSS. Also, it is difficult for developers to assess the reliability and portability of embedded OSS on a single-board computer. In this paper, we propose a method of software reliability assessment based on flexible hazard rates for the embedded OSS. Also, we analyze actual data of software failure-occurrence time-intervals to show numerical examples of software reliability assessment for the embedded OSS. Moreover, we compare the proposed hazard rate model for the embedded OSS with the typical conventional hazard rate models by using the comparison criteria of goodness-of-fit. Furthermore, we discuss the optimal software release problem for the porting-phase based on the total expected software maintenance cost.

  2. 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

  3. Review and Evaluation of Army Aviation Depot NDI (Nondestructive Inspection) and Reliability Centered Maintenance

    Science.gov (United States)

    1988-08-31

    TAILBOOM ATTACH FITTINC UPPER & LOWER RH 2n _3 S C Y J D U R FUELL CELL AFT BULKHEAD PANEl. R/H Ib 54 S C Y J D U R FUEL CELL UPPER OUTBOARD PANEL R/H...in the real world. terns i-n tnis cIass are generally simple (so-called "sg- cell ") components such as tarts wich are subject to metal ’atizue or otner...AH-64 airframe, the automated airframe logbooK, the upgraded RCA data base management system, the ACE/AACE, CFD, PEM , breakout and other programs as

  4. Implementing Reliability Centered Maintenance (RCM) with State of the Art PT&I Technologies

    Science.gov (United States)

    Hollis, Sean; Sasser, Chase

    2016-01-01

    Building on the work that was started two decades ago, Jacobs Space Operations Group has utilized state of the art PTI technologies to assess the current condition of the assets they manage under the Test and Operations Support Contract (TOSC). Specifically, the Asset Management department leveraged the benefits of ultrasound technology to quantify a motor issue in the Liquid Oxygen Storage Area, and troubleshoot the sources prior to loading the tank to perform Verification and Validation (VV) activities. This technology was efficient, easy to implement, and provided system engineers with data on a possible source of the problem. In situations where legacy motors are exhibiting unexpected noises, it may seem easier to remove and refurbish the motor and replace the bearings because that solution resolves most of the common causes of the noise. However, that solution would have involved additional spending and may not have solved issues stemming from the foundation, if those existed. By utilizing the ultrasound equipment provided by UE Systems, the sound profiles allowed Jacobs TOSC team to determine that the issue resembled a faulty bearing. After replacing the bearing, the unexpected noise ceased.

  5. Advanced diagnostics and predictive maintenance to improve availability and reliability of ENEL plants

    Energy Technology Data Exchange (ETDEWEB)

    Cenci, V.; Ghironi, M.; Guidi, L.; Lauro, M.; Pestonesi, D. [ENEL (Italy). Generation and Energy Management Division

    2007-07-01

    This paper reviews the ENEL Generation and Energy Management strategy for diagnostics and predictive maintenance of power plants and provides a comprehensive description of effective applications and systems. Exploiting the most advanced information and communication technologies makes it possible to capture weak and hidden signals and powerful processing can be used to discover forewarning symptoms and identify anomalies both in the process and, above all, inside the devices. The following systems and applications are presented together with results and impact on plant profitability: expert system for the diagnostics of plant main machinery; advanced diagnostics of 'intelligent' fieldbus devices such as on/off valve motor-driven actuators, control-valve positioners and pneumatic actuators, transmitters; control loop and control valve diagnostics in order to investigate valve friction with an estimation of the residual time to failure; multisensorial diagnostics for coal transport and storage systems aimed at preventing firing and structural damages; and wireless sensor networks for the diagnostics of medium and small size components. 4 refs., 14 figs., 1 tab.

  6. Integrated Technical Information for the Air Logistics Center: Enhancing Maintenance Technician Task Performance

    National Research Council Canada - National Science Library

    Mitta, Deborah

    1998-01-01

    This technical paper documents the final results of an analysis of the task environment under which depot maintenance technicians perform their jobs--specifically, programmed depot maintenance (PDM) for F-15 aircraft...

  7. Engineering, maintenance, and initiatives to improve LAMPF beam availability and system reliability

    International Nuclear Information System (INIS)

    Harris, H.W.; DeHaven, R.A.; Hart, V.E.; Parsons, W.M.; Sturrock, J.C.

    1992-01-01

    Two different requirements are driving engineering studies and hardware development to improve LAMPF. The first is concerned with component and system improvements to increase beam availability during the LAMPF production cycle. Hardware changes in RF, power supplies, and magnets are being implemented to increase mean time between failure and reduce time to replace or repair failed units. A joint LAMPF-Industry project is on-going to improve reliability of RF components. A component test stand is being refurbished to include significant development capability. The second approach includes several changes that will increase the duty factor of the existing accelerator. Major changes are being evaluated for replacing the front end of the accelerator. Other changes improving the high brightness capability could result in a new performance plateau for LAMPF. 2 refs., 2 figs

  8. Engineering, maintenance, and new initiatives to improve LAMPF beam availability and system reliability

    International Nuclear Information System (INIS)

    Harris, H.W.; DeHaven, R.A.; Hart, V.E.; Parsons, W.M.; Sturrock, J.C.

    1992-01-01

    Two different requirements are driving engineering studies and hardware development to improve LAMPF. The first is concerned with component and system improvements to increase beam availability during the LAMPF production cycle. Hardware changes in RF, power supplies, and magnets are being implemented to increase mean time between failure and reduce time to replace or repair failed units. A joint LAMPF-Industry project is on-going to improve reliability of RF components. A component test stand is being refurbished to include significant development capability. The second approach includes several changes that will increase the duty factor of the existing accelerator. Major changes are being evaluated for replacing the front end of the accelerator. Other changes improving high brightness capability could result in a new performance plateau for LAMPF

  9. Mobile equipment maintenance at Elk Valley Coal Corporation Fording River

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2006-07-01

    Major loading and support equipment, haul trucks, and the number of staff and hourly tradesmen working in the maintenance manpower division at Elk Valley Coal are listed. Maintenance strategies are safety, high maintenance of equipment availabilities and reliability, cost reduction, and maximized productivity of assets. Maintenance assets comprise a large shop, shovel and drill crew, machine shop, light vehicle facility, line crew, radio technicians, and cranes. Most maintenance work is completed in- house. Fording River uses a Computerized Maintenance Management System (CMMS) that was developed in-house to match business needs. Several examples of the application of Reliability Centered Maintenance (RCM) are described. 12 figs., 2 tabs.

  10. Research on operation and maintenance support system adaptive to human recognition and understanding in human-centered plant

    International Nuclear Information System (INIS)

    Numano, Masayoshi; Matsuoka, Takeshi; Mitomo, N.

    2004-01-01

    As a human-centered plant, advanced nuclear power plant needs appropriate role sharing between human and mobile intelligent agents. Human-machine cooperation for plant operation and maintenance activities is also required with an advanced interface. Plant's maintenance is programmed using mobile robots working under the radiation environments instead of human beings. Operation and maintenance support system adaptive to human recognition and understanding should be developed to establish adequate human and machine interface so as to induce human capabilities to the full and enable human to take responsibility for plan's operation. Plant's operation and maintenance can be cooperative activities between human and intelligent automonous agents having surveillance and control functions. Infrastructure of multi-agent simulation system for the support system has been investigated and developed based on work plans derived from the scheduler. (T. Tanaka)

  11. Maintenance optimization after RCM

    International Nuclear Information System (INIS)

    Doyle, E.K.; Lee, C.-G.; Cho, D.

    2005-01-01

    Variant forms of RCM (Reliability Centered Maintenance) have been the maintenance optimizing tools of choice in industry for the last 20 years. Several such optimization techniques have been implemented at the Bruce Nuclear Station. Further cost refinement of the Station preventive maintenance strategy whereby decisions are based on statistical analysis of historical failure data are now being evaluated. The evaluation includes a requirement to demonstrate that earlier optimization projects have long term positive impacts. This proved to be a significant challenge. Eventually a methodology was developed using Crowe/AMSAA (Army Materials Systems Analysis Activity) plots to justify expenditures on further optimization efforts. (authors)

  12. Reliability and maintenance in European nuclear power plants: A structural analysis of a controlled stochastic process

    International Nuclear Information System (INIS)

    Sturm, R.

    1991-01-01

    Two aspects of performance are of main concern: plant availability and plant reliability (defined as the conditional probability of an unplanned shutdown). The goal of the research is a unified framework that combines behavioral models of optimizing agents with models of complex technical systems that take into account the dynamic and stochastic features of the system. In order to achieve this synthesis, two liens of work are necessary. One line requires a deeper understanding of complex production systems and the type of data they give rise to; the other line involves the specification and estimation of a rigorously specified behavioral model. Plant operations are modeled as a controlled stochastic process, and the sequence of up and downtime spells is analyzed during failure time and point process models. Similar to work on rational expectations and structural econometric models, the behavior model of how the plant process is controlled is formulated at the level of basic processes, i.e., the objective function of the plant manager, technical constraints, and stochastic disturbances

  13. Use of knowledge based systems for rational reliability analysis based inspection and maintenance planning for offshore structures

    International Nuclear Information System (INIS)

    Tang, M.X.; Dharmavasan, S.; Peers, S.M.C.

    1994-01-01

    The structural integrity of fixed offshore platforms is ensured by periodic inspections. In the past, decisions made as to when, where and how to inspect have been made by engineers using rules-of-thumb and general planning heuristics. It is now hoped that more rational inspection and maintenance scheduling may be carried out by applying recently developed techniques based on structural reliability methods. However, one of the problems associated with a theoretical approach is that it is not always possible to incorporate all the constraints that are present in a practical situation. These constraints modify the decisions made for analysis data input and the interpretation of the analysis results. Knowledge based systems provide a mean of encapsulating several different forms of information and knowledge within a computer system and hence can overcome this problem. In this paper, a prototype system being developed for integrating reliability based analysis with other constraints for inspection scheduling will be described. In addition, the scheduling model and the algorithms to carry out the scheduling will be explained. Furthermore, implementation details are also given

  14. The carbon footprints of home and in-center maintenance hemodialysis in the United Kingdom.

    Science.gov (United States)

    Connor, Andrew; Lillywhite, Robert; Cooke, Matthew W

    2011-01-01

    Climate change presents a global health threat. However, the provision of healthcare, including dialysis, is associated with greenhouse gas emissions. The aim of this study was to determine the carbon footprints of the differing modalities and treatment regimes used to deliver maintenance hemodialysis (HD), in order to inform carbon reduction strategies at the level of both individual treatments and HD programs. This was a component analysis study adhering to PAS2050. Emissions factors were applied to data that were collected for building energy use, travel and procurement. Thrice weekly in-center HD has a carbon footprint of 3.8 ton CO2 Eq per patient per year. The majority of emissions arise within the medical equipment (37%), energy use (21%), and patient travel (20%) sectors. The carbon footprint of providing home HD varies with the regime. For standard machines: 4 times weekly (4 days, 4.5 hours), 4.3 ton CO2 Eq; 5 times weekly (5 days, 4 hours), 5.1 ton CO2 Eq ; short daily (6 days, 2 hours), 5.2 ton CO2 Eq; nocturnal (3 nightly, 7 hours), 3.9 ton CO2 Eq; and nocturnal (6 nightly, 7 hours), 7.2 ton CO2 Eq. For NxStage equipment: short daily (5.5 days, 3 hours), 1.8 ton CO2 Eq; 6 nightly nocturnal (2.1 ton CO2 Eq). The carbon footprint of HD is influenced more by the frequency of treatments than by their duration. The anticipated rise in the prevalence of home HD patients, dialyzing more frequently and for longer than in-center patients, will increase the emissions associated with HD programs (despite reductions in patient travel emissions). Emerging technologies, such as NxStage, might offer a solution to this problem. © 2011 The Authors. Hemodialysis International © 2011 International Society for Hemodialysis.

  15. Supply Warehouse#3, SWMU 088 Operations, Maintenance, and Monitoring Report Kennedy Space Center, Florida

    Science.gov (United States)

    Murphy, Alex

    2016-01-01

    This document presents the findings, observations, and results associated with Operations, Maintenance, and Monitoring (OM&M) activities of Corrective Measures Implementation (CMI) activities conducted at Supply Warehouse #3 (SW3) located at John F. Kennedy Space Center (KSC), Florida from October 8, 2015, to September 12, 2016, and performance monitoring results for semi-annual sampling events conducted in March and September 2016. The primary objective of SW3 CMI is to actively decrease concentrations of trichloroethene (TCE) and vinyl chloride (VC) to less than Florida Department of Environmental Protection (FDEP) Natural Attenuation Default Concentrations (NADCs), and the secondary objective is to reduce TCE, cis-1,2-dichloroethene (cDCE), trans-1,2-dichloroethene (tDCE), 1,1-dichloroethene (11DCE), and VC concentrations to less than FDEP Groundwater Cleanup Target Levels (GCTLs). The SW3 facility has been designated Solid Waste Management Unit (SWMU) 088 under KSC's Resource Conservation and Recovery Act (RCRA) Corrective Action Program. Based on the results to date, the SW3 air sparging (AS) system is operating at or below the performance criteria as presented in the 2008 SW3 Corrective Measures Implementation (CMI) Work Plan and 2009 and 2012 CMI Work Plan Addenda. Since the start of AS system operations on December 19, 2012, through the September 2016 groundwater sampling event, TCE concentrations have decreased to less than the GCTL in all wells within the Active Remediation Zone (ARZ), and VC results remain less than NADC but greater than GCTL. Based on these results, team consensus was reached at the October 2016 KSC Remediation Team (KSCRT) meeting to continue AS system operations and semi-annual performance monitoring of volatile organic compounds in March 2017 at ten monitoring wells at select locations, and in September 2017 at four monitoring wells at select locations to reduce VC concentrations to below GCTL. Additionally, surface water samples

  16. Maintenance planning for nuclear power plants

    International Nuclear Information System (INIS)

    Mattu, R.K.; Cooper, S.E.; Lauderdale, J.R.

    2004-01-01

    Maintenance planning for nuclear power plants is similar to that in other industrial plants but it is heavily influenced by regulatory rules, with consequent costs of compliance. Steps by the nuclear industry and the Nuclear Regulatory Commission to address that problem include development of guidelines for maintenance of risk-critical equipment, using PRA-based techniques to select a set of equipment that requires maintenance and reliability-centered maintenance (RCM) approaches for determining what maintenance is required. The result of the process is a program designed to ensure effective maintenance of the equipment most critical to plant safety. (author)

  17. Methodology for maintenance analysis based on hydroelectric power stations reliability; Metodologia para realizar analisis de mantenimiento basado en confiabilidad en centrales hidroelectricas

    Energy Technology Data Exchange (ETDEWEB)

    Rea Soto, Rogelio; Calixto Rodriguez, Roberto; Sandoval Valenzuela, Salvador; Velasco Flores, Rocio; Garcia Lizarraga, Maria del Carmen [Instituto de Investigaciones Electricas, Cuernavaca, Morelos (Mexico)

    2012-07-01

    A methodology to carry out Reliability Centered Maintenance (RCM) studies for hydroelectric power plants is presented. The methodology is an implantation/extension of the guidelines proposed by the Engineering Society for Advanced Mobility Land, Sea and Space in the SAE-JA1012 standard. With the purpose of answering the first five questions, that are set out in that standard, the use of standard ISO14224 is strongly recommended. This approach standardizes failure mechanisms and homogenizes RCM studies with the process of collecting failure and maintenance data. The use of risk matrixes to rank the importance of each failure based on a risk criteria is also proposed. [Spanish] Se presenta una metodologia para realizar estudios de mantenimiento Basado en Confiabilidad (RCM) aplicados a la industria hidroelectrica. La metodologia es una implantacion/ extension realizada por los autores de este trabajo, de los lineamientos propuestos por la Engineering Society for Advanced Mobility Land, Sea and Space en el estandar SAE-JA1012. Para contestar las primeras cinco preguntas del estandar se propone tomar como base los modos y mecanismos de fallas de componentes documentados en la guia para recopilar datos de falla en el estandar ISO-14224. Este enfoque permite estandarizar la descripcion de mecanismos de fallas de los equipos, tanto en el estudio RCM como en el proceso de recopilacion de datos de falla y de mantenimiento, lo que permite retroalimentar el ciclo de mejora continua de los procesos RCM. Tambien se propone el uso de matrices de riesgo para jerarquizar la importancia de los mecanismos de falla con base en el nivel de riesgo.

  18. The right maintenance on the right components, at the right time, with the right parts: maintaining high plant reliability through an effective maintenance program

    International Nuclear Information System (INIS)

    Von Hatten, P.

    2008-01-01

    The objective of the maintenance program at a Nuclear Power Plant is to be proactive and prevent unexpected failures of equipment that can impact on Nuclear or Conventional Safety and Plant Production. This does not mean that all equipment failures will be prevented; in a number of cases the most cost effective solution is to allow equipment to run to failure. Deciding what components are critical to the plant is the first step. The industry uses guidance from INPO Advanced Process, AP913, to classify components as Critical, Non Critical or Run to Failure based on the consequence of the failure. Once this is complete, then the right maintenance program needs to be specified. This is done through utilization of experience from the industry based on the type of component. Maintenance strategies and templates have been produced for most power plant components. Each station or fleet needs then to apply the criteria, with exceptions as required, to determine the maintenance requirements and frequency for their components. This includes predictive and preventative maintenance. The more critical the component is the more rigorous the maintenance requirements. Once the maintenance program is defined it can be implemented. This requires that the Preventative Maintenance (PM's) are updated to ensure the correct tasks are in place and the frequency is correct. Work Management will group the PM's so they can scheduled efficiently and to minimize equipment down time. The last element is to ensure that the required parts are specified and are stocked or readily available for the maintenance when it is scheduled. This is an ongoing effort since components become obsolete or suppliers go out of business or change hands. (author)

  19. Johnson Space Center's Risk and Reliability Analysis Group 2008 Annual Report

    Science.gov (United States)

    Valentine, Mark; Boyer, Roger; Cross, Bob; Hamlin, Teri; Roelant, Henk; Stewart, Mike; Bigler, Mark; Winter, Scott; Reistle, Bruce; Heydorn,Dick

    2009-01-01

    The Johnson Space Center (JSC) Safety & Mission Assurance (S&MA) Directorate s Risk and Reliability Analysis Group provides both mathematical and engineering analysis expertise in the areas of Probabilistic Risk Assessment (PRA), Reliability and Maintainability (R&M) analysis, and data collection and analysis. The fundamental goal of this group is to provide National Aeronautics and Space Administration (NASA) decisionmakers with the necessary information to make informed decisions when evaluating personnel, flight hardware, and public safety concerns associated with current operating systems as well as with any future systems. The Analysis Group includes a staff of statistical and reliability experts with valuable backgrounds in the statistical, reliability, and engineering fields. This group includes JSC S&MA Analysis Branch personnel as well as S&MA support services contractors, such as Science Applications International Corporation (SAIC) and SoHaR. The Analysis Group s experience base includes nuclear power (both commercial and navy), manufacturing, Department of Defense, chemical, and shipping industries, as well as significant aerospace experience specifically in the Shuttle, International Space Station (ISS), and Constellation Programs. The Analysis Group partners with project and program offices, other NASA centers, NASA contractors, and universities to provide additional resources or information to the group when performing various analysis tasks. The JSC S&MA Analysis Group is recognized as a leader in risk and reliability analysis within the NASA community. Therefore, the Analysis Group is in high demand to help the Space Shuttle Program (SSP) continue to fly safely, assist in designing the next generation spacecraft for the Constellation Program (CxP), and promote advanced analytical techniques. The Analysis Section s tasks include teaching classes and instituting personnel qualification processes to enhance the professional abilities of our analysts

  20. North American nuclear maintenance best practices compared to Japanese utility maintenance practices

    International Nuclear Information System (INIS)

    Harazim, M.L.; Ferguson, B.J.

    2003-01-01

    The purpose of this paper is to compare the best practices in North America concerning Preventive Maintenance, Predictive Maintenance and Reliability Centered Maintenance (RCM) or Preventive Maintenance Optimization (PMO) with the time-directed maintenance philosophies utilized by Japanese utilities, and how the Japanese utilities are considering (and some have begun) adopting North American ways of doing business. Preventive Maintenance Living Programs are also discussed, along with the Institute of Nuclear Power Operations AP-913 process, Equipment Reliability Process. Also, a cost benefit analysis will be demonstrated showing how major cost savings can be achieved by shifting from a predominantly time-directed maintenance philosophy to a predominantly predictive strategy utilizing vibration analysis, lubricating oil analysis, thermography and other predictive technologies to better utilize resources, reduce spare part consumption and to minimize maintenance induced errors. As a result of the strides made while incorporating these new philosophies, we no longer advocate tearing apart perfectly good equipment. (author)

  1. Analysis and validation center for ITER RH maintenance scenarios in a virtual environment

    NARCIS (Netherlands)

    Elzendoorn, B. S. Q.; M.R. de Baar,; Hamilton, D.; Heemskerk, C. J. M.; Koning, J. F.; Ronden, D. M. S.

    2012-01-01

    A facility for detailed simulation of maintenance processes in the ITER Hot Cell Facility (HCF) has been taken into operation. The facility mimics the Remote Handling (RH) work-cells as are presently foreseen. Novel virtual reality (VR) technology, extended with a physics engine is used to create a

  2. Study on the methodology for predicting and preventing errors to improve reliability of maintenance task in nuclear power plant

    International Nuclear Information System (INIS)

    Hanafusa, Hidemitsu; Iwaki, Toshio; Embrey, D.

    2000-01-01

    The objective of this study was to develop and effective methodology for predicting and preventing errors in nuclear power plant maintenance tasks. A method was established by which chief maintenance personnel can predict and reduce errors when reviewing the maintenance procedures and while referring to maintenance supporting systems and methods in other industries including aviation and chemical plant industries. The method involves the following seven steps: 1. Identification of maintenance tasks. 2. Specification of important tasks affecting safety. 3. Assessment of human errors occurring during important tasks. 4. Identification of Performance Degrading Factors. 5. Dividing important tasks into sub-tasks. 6. Extraction of errors using Predictive Human Error Analysis (PHEA). 7. Development of strategies for reducing errors and for recovering from errors. By way of a trial, this method was applied to the pump maintenance procedure in nuclear power plants. This method is believed to be capable of identifying the expected errors in important tasks and supporting the development of error reduction measures. By applying this method, the number of accidents resulting form human errors during maintenance can be reduced. Moreover, the maintenance support base using computers was developed. (author)

  3. Prediction of attendance at fitness center: a comparison between the theory of planned behavior, the social cognitive theory, and the physical activity maintenance theory

    OpenAIRE

    Jekauc, Darko; Völkle, Manuel; Wagner, Matthias O.; Mess, Filip; Reiner, Miriam; Renner, Britta

    2015-01-01

    In the processes of physical activity (PA) maintenance specific predictors are effective, which differ from other stages of PA development. Recently, Physical Activity Maintenance Theory (PAMT) was specifically developed for prediction of PA maintenance. The aim of the present study was to evaluate the predictability of the future behavior by the PAMT and compare it with the Theory of Planned Behavior (TPB) and Social Cognitive Theory (SCT). Participation rate in a fitness center was observed...

  4. Degradation mode analysis: An approach to establish effective predictive maintenance tasks

    International Nuclear Information System (INIS)

    Sonnett, D.E.; Douglass, P.T.; Barnard, D.D.

    1991-01-01

    A significant number of nuclear generating stations have been employing Reliability Centered Maintenance methodology to arrive at applicable and effective maintenance tasks for their plant equipment. The resultant endpoint of most programs has been an increased emphasis on predictive maintenance as the task of choice for monitoring and trending plant equipment condition to address failure mechanisms of the analyses. Many of these plants have spent several years conducting reliability centered analysis before they seriously begin implementing predictive program improvements. In this paper we present another methodology, entitled Degradation Mode Analysis, which provides a more direct method to quickly and economically achieve the major benefit of reliability centered analysis, namely predictive maintenance. (author)

  5. Analysis and validation center for ITER RH maintenance scenarios in a virtual environment

    International Nuclear Information System (INIS)

    Elzendoorn, B.S.Q.; Baar, M. de; Hamilton, D.; Heemskerk, C.J.M.; Koning, J.F.; Ronden, D.M.S.

    2012-01-01

    A facility for detailed simulation of maintenance processes in the ITER Hot Cell Facility (HCF) has been taken into operation. The facility mimics the Remote Handling (RH) work-cells as are presently foreseen. Novel virtual reality (VR) technology, extended with a physics engine is used to create a realistic setting in which a team of Remote Handling (RH) operators can interact with a virtual Hot Cell environment. The physics engine is used to emulate the Hot Cell behavior and to provide tactile feed-back of the (virtual) slave. Multi-operator maintenance scenarios can be developed and tested in virtual reality. Complex interactions between the RH operators and the HCF control system software will be tested. Task performance will be quantified and operational resource consumption will be estimated.

  6. Analysis and validation center for ITER RH maintenance scenarios in a virtual environment

    Energy Technology Data Exchange (ETDEWEB)

    Elzendoorn, B.S.Q., E-mail: B.S.Q.Elzendoorn@rijnhuizen.nl [FOM-Institute for Plasma Physics Rijnhuizen, Association EURATOM-FOM, Partner in the Trilateral Euregio Cluster and ITER-NL, PO Box 1207, 3430 BE, Nieuwegein (Netherlands); Baar, M. de [FOM-Institute for Plasma Physics Rijnhuizen, Association EURATOM-FOM, Partner in the Trilateral Euregio Cluster and ITER-NL, PO Box 1207, 3430 BE, Nieuwegein (Netherlands); Hamilton, D. [ITER Organization, Route de Vinon-sur-Verdon, CS 90 046, 13067 St. Paul-lez-Durance Cedex (France); Heemskerk, C.J.M. [Heemskerk Innovative Technology, Sassenheim (Netherlands); Koning, J.F.; Ronden, D.M.S. [FOM-Institute for Plasma Physics Rijnhuizen, Association EURATOM-FOM, Partner in the Trilateral Euregio Cluster and ITER-NL, PO Box 1207, 3430 BE, Nieuwegein (Netherlands)

    2012-03-15

    A facility for detailed simulation of maintenance processes in the ITER Hot Cell Facility (HCF) has been taken into operation. The facility mimics the Remote Handling (RH) work-cells as are presently foreseen. Novel virtual reality (VR) technology, extended with a physics engine is used to create a realistic setting in which a team of Remote Handling (RH) operators can interact with a virtual Hot Cell environment. The physics engine is used to emulate the Hot Cell behavior and to provide tactile feed-back of the (virtual) slave. Multi-operator maintenance scenarios can be developed and tested in virtual reality. Complex interactions between the RH operators and the HCF control system software will be tested. Task performance will be quantified and operational resource consumption will be estimated.

  7. Preventative Maintenance.

    Science.gov (United States)

    Migliorino, James

    Boards of education must be convinced that spending money up front for preventive maintenance will, in the long run, save districts' tax dollars. A good program of preventive maintenance can minimize disruption of service; reduce repair costs, energy consumption, and overtime; improve labor productivity and system equipment reliability; handle…

  8. Framatome and the maintenance of nuclear power plant. An approach of reactivity in the reliability of interventions

    International Nuclear Information System (INIS)

    Hertzog, D.

    1997-01-01

    This text gives a commentary on the dispositions taken by Framatome to come with the operators face to the new stakes in their operations of maintenance and particularly, the reduction of costs and dosimetry of intervention. (N.C.)

  9. A Novel Measure of "Good" Mentoring: Testing Its Reliability and Validity in Four Academic Health Centers.

    Science.gov (United States)

    Pololi, Linda H; Evans, Arthur T; Civian, Janet T; Gibbs, Brian K; Gillum, Linda H; Brennan, Robert T

    2016-01-01

    Despite the well-recognized benefits of mentoring in academic medicine, there is a lack of clarity regarding what constitutes effective mentoring. We developed a tool to assess mentoring activities experienced by faculty and evaluated evidence for its validity. The National Initiative on Gender, Culture, and Leadership in Medicine-"C-Change"-previously developed the C-Change Faculty Survey to assess the culture of academic medicine. After intensive review, we added six items representing six components of mentoring to the survey-receiving help with career and personal goals, learning skills, sponsorship, and resources. We tested the items in four academic health centers during 2013 to 2014. We estimated reliability of the new items and tested the correlation of the new items with a mentoring composite variable representing faculty mentoring experiences as positive, neutral, or inadequate and with other C-Change dimensions of culture. Among the 1520 responding faculty (response rate 61-63%), there was a positive association between each of the six mentoring activities and satisfaction with both the amount and quality of mentoring received. There was no difference by sex. Cronbach α coefficients ranged from 0.89 to 0.95 across subgroups of faculty (by sex, race, and principal roles). The mentoring responses were associated most closely with dimensions of Institutional Support (r = 0.58, P Mentoring scale is a valid instrument to assess mentoring. Survey results could facilitate mentoring program development and evaluation.

  10. Application of the reliability theory on the analysis of the effects of sbwr' main control console maintenance

    International Nuclear Information System (INIS)

    Widagdo, S.

    1997-01-01

    Maintenance activities on the main control console, which is a primary element of the man-machine interface system, are a source of concern. this concern has been arisen since the main control function is the central part to observe and control the reactor operation. the paper will discuss a study of the effects of main control console maintenance activity upon the operability of SBWR. the first step is learning the SBWR main control room design in order to know its monitoring and controlling capability and then makes an assumption of maintenance requirement followed by an evaluation of the effects of the maintenance activity. it is assumed that 2 years or equivalent to 17.520 hours are the reference time for one cycle operation of SBWR. the aim is to identify any adverse effects and eliminate or minimize them through design improvements. the evaluation method used here is the reability theory R(t) = e sup-λt. Based on the result of the evaluation can be concluded that there are no negative effects of maintenance activity upon the operability of the SBWR

  11. FAMILY BEHAVIOR IN MAINTENANCE STATUS HB CHRONIC RENAL FAILURE PATIENTS THROUGH FAMILY CENTERED CARE APPROACH OF DIET FE MANAGEMENT

    Directory of Open Access Journals (Sweden)

    Anggia Fajar Hardianti

    2017-04-01

    Full Text Available Introduction: Erythropoietic agent as standard practice for anemia treatment, which has a function to increase the value of hemoglobin (Hb to 12 g/dl in patients with chronic renal failure (CRF, who receiving dialysis treatment. The use of erythropoietin has to keep of the iron/Fe amount in the body. Family who have a duty of care should have knowledge, attitude, and behavior to maintain patient’s Hb by giving support to the patient to obey the Fe diet. The aimed of this study was to investigate the effect of family centered care approach in management Fe diet toward family’s behaviour in maintenance Hb level of CRF patients in hemodialysis ward, Gambiran Hospital, Kediri. Method: This study was used a pre experimental design. Total sample were 10 respondents, who met to inclusion criteria. The independent variables were knowledge, attitude, and psychomotor of family in maintenance of Hb level in CRF’s patients. The dependent variable was Fe diet management with family centered care approach. Data was collected by using a structured questionnaire and home visit observation. Result: Data was analyzed by using Wilcoxon Sign Rank Test with significance level α≤0.05. Results showed that Fe diet management with family centered care approach took effect to family’s knowledge (p=0.011, family’s attitude (p=0.005 and family’s psychomotor (p=0.005 in maintenance Hb level of CRF patients. Discussion: Family’s knowledge, attitude, and psychomotor were effected by experiences during the care of a patient, not affordable to access information and patient’s own decision. The strengths and weaknesses in the family to got a better plan of care can be made by discuss and sharing among researcher, patient and his family. It can be concluded that Fe diet management with family centered care approach took effect to family’s behaviour. Further studies should involve larger respondents and better measurement tools to obtain more accurate results.

  12. Validating and calibrating the Nintendo Wii balance board to derive reliable center of pressure measures.

    Science.gov (United States)

    Leach, Julia M; Mancini, Martina; Peterka, Robert J; Hayes, Tamara L; Horak, Fay B

    2014-09-29

    The Nintendo Wii balance board (WBB) has generated significant interest in its application as a postural control measurement device in both the clinical and (basic, clinical, and rehabilitation) research domains. Although the WBB has been proposed as an alternative to the "gold standard" laboratory-grade force plate, additional research is necessary before the WBB can be considered a valid and reliable center of pressure (CoP) measurement device. In this study, we used the WBB and a laboratory-grade AMTI force plate (AFP) to simultaneously measure the CoP displacement of a controlled dynamic load, which has not been done before. A one-dimensional inverted pendulum was displaced at several different displacement angles and load heights to simulate a variety of postural sway amplitudes and frequencies (<1 Hz). Twelve WBBs were tested to address the issue of inter-device variability. There was a significant effect of sway amplitude, frequency, and direction on the WBB's CoP measurement error, with an increase in error as both sway amplitude and frequency increased and a significantly greater error in the mediolateral (ML) (compared to the anteroposterior (AP)) sway direction. There was no difference in error across the 12 WBB's, supporting low inter-device variability. A linear calibration procedure was then implemented to correct the WBB's CoP signals and reduce measurement error. There was a significant effect of calibration on the WBB's CoP signal accuracy, with a significant reduction in CoP measurement error (quantified by root-mean-squared error) from 2-6 mm (before calibration) to 0.5-2 mm (after calibration). WBB-based CoP signal calibration also significantly reduced the percent error in derived (time-domain) CoP sway measures, from -10.5% (before calibration) to -0.05% (after calibration) (percent errors averaged across all sway measures and in both sway directions). In this study, we characterized the WBB's CoP measurement error under controlled, dynamic

  13. The Center for Epidemiologic Studies Depression Scale: Factor Validity and Reliability in a French Sample of Adolescents with Intellectual Disability

    Science.gov (United States)

    Maiano, Christophe; Morin, Alexandre J. S.; Begarie, Jerome

    2011-01-01

    The purpose of this study was to test the factor validity and reliability of the Center for Epidemiologic Studies Depression Scale (CES-D) within a sample of adolescents with mild to moderate Intellectual Disability (ID). A total sample of 189 adolescents (121 boys and 68 girls), aged between 12 and 18 years old, with mild to moderate ID were…

  14. Human-centered modeling in human reliability analysis: some trends based on case studies

    International Nuclear Information System (INIS)

    Mosneron-Dupin, F.; Reer, B.; Heslinga, G.; Straeter, O.; Gerdes, V.; Saliou, G.; Ullwer, W.

    1997-01-01

    As an informal working group of researchers from France, Germany and The Netherlands created in 1993, the EARTH association is investigating significant subjects in the field of human reliability analysis (HRA). Our initial review of cases from nuclear operating experience showed that decision-based unrequired actions (DUA) contribute to risk significantly on the one hand. On the other hand, our evaluation of current HRA methods showed that these methods do not cover such actions adequately. Especially, practice-oriented guidelines for their predictive identification are lacking. We assumed that a basic cause for such difficulties was that these methods actually use a limited representation of the stimulus-organism-response (SOR) paradigm. We proposed a human-centered model, which better highlights the active role of the operators and the importance of their culture, attitudes and goals. This orientation was encouraged by our review of current HRA research activities. We therefore decided to envisage progress by identifying cognitive tendencies in the context of operating and simulator experience. For this purpose, advanced approaches for retrospective event analysis were discussed. Some orientations for improvements were proposed. By analyzing cases, various cognitive tendencies were identified, together with useful information about their context. Some of them match psychological findings already published in the literature, some of them are not covered adequately by the literature that we reviewed. Finally, this exploratory study shows that contextual and case-illustrated findings about cognitive tendencies provide useful help for the predictive identification of DUA in HRA. More research should be carried out to complement our findings and elaborate more detailed and systematic guidelines for using them in HRA studies

  15. Paranal maintenance and CMMS experience

    Science.gov (United States)

    Montano, Nelson

    2004-10-01

    During the last four years of operations, low technical downtime has been one of the relevant records of the Paranal Observatory. From the beginning of the Very Large Telescope (VLT) project, European Southern Observatory (ESO) has considered the implementation of a proper maintenance strategy a fundamental point in order to ensure low technical down time and preserve the Observatory's assets. The implementation of the maintenance strategy was based on the following aspects: - Strong maintenance sense during the design stage. Line Replacement Unit (LRU) concept, standardization and modularity of the Observatory equipment - Creation of a dedicated team for Maintenance - The implementation of a Computerized Maintenance Management System After four operational years, the result of these aspects has exceeded the expectations; the Observatory has been operating with high availability under a sustainable strategy. The strengths of the maintenance strategy have been based on modern maintenance concepts applied by regular production companies, where any minute of down time involves high cost. The operation of the actual Paranal Maintenance System is based mainly on proactive activities, such as regular inspections, preventive maintenance (PM) and predictive maintenance (PdM) plans. Nevertheless, it has been necessary to implement a strong plan for corrective maintenance (CM). The Spare Parts Strategy has also been an important point linked to the Maintenance Strategy and CMMS implementation. At present, almost 4,000 items related to the Observatory spare parts are loaded into the CMMS database. Currently, we are studying the implementation of a Reliability Centered Maintenance (RCM) project in one of our critical systems The following document presents the actual status of the Paranal Maintenance Strategy and which have been the motivations to implement the established strategy.

  16. Upgrade of maintenance technologies of Nuclear Power Plants

    International Nuclear Information System (INIS)

    Kamada, Kazuaki

    2005-01-01

    In order to enhance long-term safe and stable operation of Ikata Nuclear Power Plants (NPPs) in more efficient way, maintenance technology upgrade project was started aiming at establishment of simplified and efficient self-maintenance system with affiliated companies. Maintenance technique and supervisor qualification system was introduced after improvement and reinforcement of personnel education and training. Reflecting investigation of maintenance activities of US NPPs and productivity improvement in other industries, preventive maintenance optimization project had been performed such as introduction of key performance indicator (KPI), new system incorporating reliability-centered maintenance (RCM) and condition-based maintenance (CBM), and on-line monitoring and maintenance (OLM) based on risk assessment. Enterprise asset management (EAM) to establish information data base and total productive maintenance (TPM) action for every personnel to participate in self-maintenance was also introduced. (T. Tanaka)

  17. Research on reliability management systems for Nuclear Power Plant

    International Nuclear Information System (INIS)

    Maki, Nobuo

    2000-01-01

    Investigation on a reliability management system for Nuclear Power Plants (NPPs) has been performed on national and international archived documents as well as on current status of studies at Idaho National Engineering and Environmental Laboratory (INEEL), US NPPs (McGuire, Seabrook), a French NPP (St. Laurent-des-Eaux), Japan Atomic Energy Research Institute (JAERI), Central Research Institute of Electric Power Industries (CRIEPI), and power plant manufacturers in Japan. As a result of the investigation, the following points were identified: (i) A reliability management system is composed of a maintenance management system to inclusively manage maintenance data, and an anomalies information and reliability data management system to extract data from maintenance results stored in the maintenance management system and construct a reliability database. (ii) The maintenance management system, which is widely-used among NPPs in the US and Europe, is an indispensable system for the increase of maintenance reliability. (iii) Maintenance management methods utilizing reliability data like Reliability Centered Maintenance are applied for NPP maintenance in the US and Europe, and contributing to cost saving. Maintenance templates are effective in the application process. In addition, the following points were proposed on the design of the system: (i) A detailed database on specifications of facilities and components is necessary for the effective use of the system. (ii) A demand database is indispensable for the application of the methods. (iii) Full-time database managers are important to maintain the quality of the reliability data. (author)

  18. Study of distribution of doses in maintenance operations and interventions in restricted areas of IPEN's radiopharmacy center, Brazil

    International Nuclear Information System (INIS)

    Machado, Jessica S.; Souza, Daiane C.; Rodrigues Junior, Orlando; Gerulis, Eduardo; Todo, Alberto S.

    2013-01-01

    This research was developed at the Radiopharmacy Center of the Nuclear and Energy Research Institute - IPEN/CNEN/SP, Brazil, that performs the production of radiopharmaceuticals with isotopes of the 131 I, 123 I, 201 Tl, 67 Ga, 18 F and 99 Mo for use in nuclear medicine. The radioisotopes are produced on an industrial scale and the installation was designed to meet radiation safety standards and quality control requirements. To ensure the production, there are skilled professionals who perform the tasks of maintenance of the equipment and instruments, installed in the cells of processing of radiopharmaceuticals, without which it is not possible to conduct the work with safety and quality. This study was done a survey called Survey of Variables, based on the maintenance operations and interventions in restricted areas of the Centre of Radiopharmacy and in the survey of the distribution of doses in these tasks, carried out during the period from 2005 to 2011. This research aims to identify and determine the main variables that have an impact on the worker's dose. The results are presented for the Occupationally Exposed Individual variable, variable operation, variable area/Cell, task and Feature variable and variable duration of operation, depending on the Dose variable. It is intended in this way to contribute to improvements in operations in restricted areas that may result in lower individual doses without causing significant changes in the routine of work

  19. On maintenance management of wind and nuclear power plants

    International Nuclear Information System (INIS)

    Nilsson, Julia

    2009-11-01

    Electrical production in Sweden today is mainly from nuclear and hydro power. However, there is large increase in renewable energy like wind power and the installed new capacity goals are large. Several electrical production sources are important for the sustainability of the energy system. Maintenance is an approach for keeping a system sustainable. The importance of structured maintenance for reliable electrical production systems triggers the development of qualitative and quantitative maintenance management methods. Examples of these methods are Reliability-Centered Maintenance (RCM) which is a structured qualitative approach that focuses on reliability when planning maintenance, and Reliability Centered Asset Management (RCAM) which is a development of RCM into a quantitative approach with the aim to relate preventive maintenance to total maintenance cost and system reliability. This thesis presents models, as applications of RCAM, based on the methods of Life Cycle Cost (LCC) and mathematical optimization, applied to wind and nuclear power plants. Both deterministic and stochastic approaches have been used and the proposed models are based on the Total Cost model, which summarizes costs for maintenance and production loss, and the Aircraft model, which is an opportunistic maintenance optimization model. Opportunistic maintenance is preventive maintenance performed at opportunities. The wind power applications in this study show on different ways to cover costs of condition monitoring systems (CMS) and further on economic benefits of these when uncertainties of times to failure are included in the model. The nuclear power applications show on that the optimization model is dependent on the discount rate and that a high discount rate gives more motivation for opportunistic replacements. When put into a stochastic framework and compared to other maintenance strategies it is shown that an extended opportunistic maintenance optimization model has a good overall

  20. Validating and Calibrating the Nintendo Wii Balance Board to Derive Reliable Center of Pressure Measures

    Directory of Open Access Journals (Sweden)

    Julia M. Leach

    2014-09-01

    Full Text Available The Nintendo Wii balance board (WBB has generated significant interest in its application as a postural control measurement device in both the clinical and (basic, clinical, and rehabilitation research domains. Although the WBB has been proposed as an alternative to the “gold standard” laboratory-grade force plate, additional research is necessary before the WBB can be considered a valid and reliable center of pressure (CoP measurement device. In this study, we used the WBB and a laboratory-grade AMTI force plate (AFP to simultaneously measure the CoP displacement of a controlled dynamic load, which has not been done before. A one-dimensional inverted pendulum was displaced at several different displacement angles and load heights to simulate a variety of postural sway amplitudes and frequencies (<1 Hz. Twelve WBBs were tested to address the issue of inter-device variability. There was a significant effect of sway amplitude, frequency, and direction on the WBB’s CoP measurement error, with an increase in error as both sway amplitude and frequency increased and a significantly greater error in the mediolateral (ML (compared to the anteroposterior (AP sway direction. There was no difference in error across the 12 WBB’s, supporting low inter-device variability. A linear calibration procedure was then implemented to correct the WBB’s CoP signals and reduce measurement error. There was a significant effect of calibration on the WBB’s CoP signal accuracy, with a significant reduction in CoP measurement error (quantified by root-mean-squared error from 2–6 mm (before calibration to 0.5–2 mm (after calibration. WBB-based CoP signal calibration also significantly reduced the percent error in derived (time-domain CoP sway measures, from −10.5% (before calibration to −0.05% (after calibration (percent errors averaged across all sway measures and in both sway directions. In this study, we characterized the WBB’s CoP measurement error

  1. Study to determine the reliability and validity of a needs-assessment instrument used within the mechanical maintenance field of the nuclear electrical-generating industry

    International Nuclear Information System (INIS)

    Russell, L.O.

    1982-01-01

    This study was to determine if task parameter ratings provided by nuclear power plant maintenance mechanics assessed the true task frequency, criticality, and difficulty. This was to measure the data's usefulness as a training needs assessment indicator. A questionnaire entitled Job Task Questionnaire for Maintenance Mechanics was developed and used to collect data from job incumbents. Development was based on plant visits and incumbent interviews. Duties, tasks, parameters, and scales were then compiled to form the questionnaire. The questionnaire was then pilot tested. A random sample was selected from the national population of nuclear power plant maintenance mechanics. This resulted in a sample which was stratified across the job title and random within the job title. The descriptive analysis did not tend to indicate that the mean value of each task parameter provided a true or valid value. The overall conclusion drawn from the data analysis was that the ratings did not provide a substantially valid or reliable indication on which to base task training needs

  2. Deterministic and stochastic approach for safety and reliability optimization of captive power plant maintenance scheduling using GA/SA-based hybrid techniques: A comparison of results

    International Nuclear Information System (INIS)

    Mohanta, Dusmanta Kumar; Sadhu, Pradip Kumar; Chakrabarti, R.

    2007-01-01

    This paper presents a comparison of results for optimization of captive power plant maintenance scheduling using genetic algorithm (GA) as well as hybrid GA/simulated annealing (SA) techniques. As utilities catered by captive power plants are very sensitive to power failure, therefore both deterministic and stochastic reliability objective functions have been considered to incorporate statutory safety regulations for maintenance of boilers, turbines and generators. The significant contribution of this paper is to incorporate stochastic feature of generating units and that of load using levelized risk method. Another significant contribution of this paper is to evaluate confidence interval for loss of load probability (LOLP) because some variations from optimum schedule are anticipated while executing maintenance schedules due to different real-life unforeseen exigencies. Such exigencies are incorporated in terms of near-optimum schedules obtained from hybrid GA/SA technique during the final stages of convergence. Case studies corroborate that same optimum schedules are obtained using GA and hybrid GA/SA for respective deterministic and stochastic formulations. The comparison of results in terms of interval of confidence for LOLP indicates that levelized risk method adequately incorporates the stochastic nature of power system as compared with levelized reserve method. Also the interval of confidence for LOLP denotes the possible risk in a quantified manner and it is of immense use from perspective of captive power plants intended for quality power

  3. Reliability Information Analysis Center 1st Quarter 2007, Technical Area Task (TAT) Report

    Science.gov (United States)

    2007-02-05

    Library or [twField/Test 217Plus Ally w/ a.romtu DAAData Experience Data Need t( rdito Trqnd • s aa(Model) develol analisis Mappng & ANLED217Plu...of collected reliability data and have discovered that even with sparse data, analysis of the data shows clustering of reliability data by equipment...intended search target. Conceptually cluster discovered data to allow more detailed analysis by equipment type. For example, it may be useful to

  4. Sensor/signal monitoring and plant maintenance

    International Nuclear Information System (INIS)

    Ciftcioglu, Oe.; Tuerkcan, E.

    1994-02-01

    Nuclear Power Plant (NPO) availability is determined by the intended functionality of safety related system and components. Therefore, maintenance is an important issue in a power plant connected to the plant's reliability and safety. The traditional maintenance policies proved to be rather costly and even not effectively addressing NPP requirements. Referring to these drawbacks, in the last decade, in the nuclear reliability centered maintenance (RCM) gained substantial interest due to its merits. In the formal implementation of RCM, apparently, predictive maintenance is not considered. However, with the impact of modern real-time and on-line surveillance and monitoring methodologies, the predictive maintenance procedures like sensor/signal verification and validation are to be included into RCM. (orig.)

  5. Optimizing preventive maintenance

    International Nuclear Information System (INIS)

    DiCola, F.E.

    1988-01-01

    The traditional approach to preventive maintenance (PM) is based on adherence to manufacturers's requirements and recommended frequencies. When equipment fails, either new procedures are established or the frequency is increased. This leads to an increase in the number of PM activities, overloading not only maintenance resources, but support as well. There is no correlation between more PM and an increase in equipment reliability. More PM may actually induce failures. Reliability-centered maintenance, a new concept in utility maintenance, is based on identifying system/subsystem functions, failures, and dominant failure modes to develop or revise PM tasks. The activities described in this paper are based on actual implementation of this concept on an ongoing project to upgrade the PM program at one of the largest electric utilities in the country. Optimum PM activities are those that, when implemented, will minimize factors that c cause equipment to fail. One technique described illustrates how equipment performance, failure modes, and causes can be related to minimize the occurrence of failures. Operating history and service life of a component are key factors in determining the most effective PM activities, provided that the factors are related to failure modes and causes

  6. Savannah River Site Eastern Transportation Hub: A Concept For a DOE Eastern Packaging, Staging and Maintenance Center - 13143

    International Nuclear Information System (INIS)

    England, Jeffery L.; Adams, Karen; Maxted, Maxcine; Ruff Jr, Clarence; Albenesius, Andrew; Bowers, Mark D.; Fountain, Geoffrey; Hughes, Michael; Gordon, Sydney; O'Connor, Stephen

    2013-01-01

    The Department of Energy (DOE) is working to de-inventory sites and consolidate hazardous materials for processing and disposal. The DOE administers a wide range of certified shipping packages for the transport of hazardous materials to include Special Nuclear Material (SNM), radioactive materials, sealed sources and radioactive wastes. A critical element to successful and safe transportation of these materials is the availability of certified shipping packages. There are over seven thousand certified packagings (i.e., Type B/Type AF) utilized within the DOE for current missions. The synergistic effects of consolidated maintenance, refurbishment, testing, certification, and costing of these services would allow for efficient management of the packagings inventory and to support anticipated future in-commerce shipping needs. The Savannah River Site (SRS) receives and ships radioactive materials (including SNM) and waste on a regular basis for critical missions such as consolidated storage, stabilization, purification, or disposition using H-Canyon and HB-Line. The Savannah River National Laboratory (SRNL) has the technical capability and equipment for all aspects of packaging management. SRS has the only active material processing facility in the DOE complex and is one of the sites of choice for nuclear material consolidation. SRS is a logical location to perform maintenance and periodic testing of the DOE fleet of certified packagings. This initiative envisions a DOE Eastern Packaging Staging and Maintenance Center (PSMC) at the SRS and a western hub at the Nevada National Security Site (NNSS), an active DOE Regional Disposal Site. The PSMC's would be the first place DOE would go to meet their radioactive packaging needs and the primary locations projects would go to disposition excess packaging for beneficial reuse. These two hubs would provide the centralized management of a packaging fleet rather than the current approach to design, procure, maintain and dispose

  7. Savannah River Site Eastern Transportation Hub: A Concept For a DOE Eastern Packaging, Staging and Maintenance Center - 13143

    Energy Technology Data Exchange (ETDEWEB)

    England, Jeffery L. [Savannah River National Laboratory, Aiken, South Carolina (United States); Adams, Karen; Maxted, Maxcine; Ruff Jr, Clarence [U.S. Department of Energy, Savannah River Site, Aiken, SC (United States); Albenesius, Andrew; Bowers, Mark D.; Fountain, Geoffrey; Hughes, Michael [Savannah River Nuclear Solutions, Aiken, SC (United States); Gordon, Sydney [National Security Technologies, LLC, Las Vegas, NV (United States); O' Connor, Stephen [U.S. Department of Energy, HQ DOE, EM-33, Germantown MD (United States)

    2013-07-01

    The Department of Energy (DOE) is working to de-inventory sites and consolidate hazardous materials for processing and disposal. The DOE administers a wide range of certified shipping packages for the transport of hazardous materials to include Special Nuclear Material (SNM), radioactive materials, sealed sources and radioactive wastes. A critical element to successful and safe transportation of these materials is the availability of certified shipping packages. There are over seven thousand certified packagings (i.e., Type B/Type AF) utilized within the DOE for current missions. The synergistic effects of consolidated maintenance, refurbishment, testing, certification, and costing of these services would allow for efficient management of the packagings inventory and to support anticipated future in-commerce shipping needs. The Savannah River Site (SRS) receives and ships radioactive materials (including SNM) and waste on a regular basis for critical missions such as consolidated storage, stabilization, purification, or disposition using H-Canyon and HB-Line. The Savannah River National Laboratory (SRNL) has the technical capability and equipment for all aspects of packaging management. SRS has the only active material processing facility in the DOE complex and is one of the sites of choice for nuclear material consolidation. SRS is a logical location to perform maintenance and periodic testing of the DOE fleet of certified packagings. This initiative envisions a DOE Eastern Packaging Staging and Maintenance Center (PSMC) at the SRS and a western hub at the Nevada National Security Site (NNSS), an active DOE Regional Disposal Site. The PSMC's would be the first place DOE would go to meet their radioactive packaging needs and the primary locations projects would go to disposition excess packaging for beneficial reuse. These two hubs would provide the centralized management of a packaging fleet rather than the current approach to design, procure, maintain and

  8. Role of in-service inspection and maintenance in reliability assurance of concrete structures in nuclear plants

    International Nuclear Information System (INIS)

    Ellingwood, B.R.; Mori, Y.

    1993-01-01

    The degradation in strength of a component with random damage is evaluated using a growth model for individual damages which can be obtained from experimental data. The distribution function of damage intensity after inspection and repair is updated using a Bayesian analysis that takes the quality of inspection into account. With this posterior distribution, the time-dependent strength after the inspection and repair can be evaluated. Time-dependent reliability analysis can be used to determine inspection/repair strategies that are necessary to keep the failure probability of the component lower than an established target. (author)

  9. 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 ...

  10. Random maintenance policies

    CERN Document Server

    Nakagawa, Toshio

    2014-01-01

    Exploring random maintenance models, this book provides an introduction to the implementation of random maintenance, and it is one of the first books to be written on this subject.  It aims to help readers learn new techniques for applying random policies to actual reliability models, and it provides new theoretical analyses of various models including classical replacement, preventive maintenance and inspection policies. These policies are applied to scheduling problems, backup policies of database systems, maintenance policies of cumulative damage models, and reliability of random redundant systems. Reliability theory is a major concern for engineers and managers, and in light of Japan’s recent earthquake, the reliability of large-scale systems has increased in importance. This also highlights the need for a new notion of maintenance and reliability theory, and how this can practically be applied to systems. Providing an essential guide for engineers and managers specializing in reliability maintenance a...

  11. Status of reliability in determining SDDR for manual maintenance activities in ITER: Quality assessment of relevant activation cross sections involved

    International Nuclear Information System (INIS)

    Garcia, R.; Garcia, M.; Pampin, R.; Sanz, J.

    2016-01-01

    Highlights: • Feasibility of manual maintenance activities in ITER port cell and port interspace. • Activation of relevant materials and components placed in the current ITER model. • Dominant radionuclides and pathways for shutdown dose rate in ITER. • Quality analysis of typically used EAF and TENDL activation libraries is performed. • EAF performance found as trustworthy with slight recommended improvements. - Abstract: This paper assesses the quality of the EAF-2007 and 2010 activation cross sections for relevant reactions in the determination of the Shutdown Dose Rate (SDDR) in the Port Cell (PC) and Port Interspace (PI) areas of ITER. For each of relevant ITER materials, dominant radionuclides responsible of SDDR and their production pathways are listed. This information comes from a review of the recent reports/papers about SDDR in ITER and own calculations. A total of 26 relevant pathways are found. The quality of these cross sections pathways is assessed following EAF validation procedure, and for those found as not validated last TENDL library versions have been investigated in order to check possible improvements when compared to EAF. The use of EAF libraries is found as trustworthy and it is recommended for the prediction of SDDR in the ITER PC and PI. However, 3 cross section reactions are considered for further improvement: Co59(n,2n)Co58, Cu63(n,g)Cu64 and Cr50(n,g)Cr51.

  12. Status of reliability in determining SDDR for manual maintenance activities in ITER: Quality assessment of relevant activation cross sections involved

    Energy Technology Data Exchange (ETDEWEB)

    Garcia, R., E-mail: rgarciam@ind.uned.es [UNED, Power Engineering Department, C/Juan del Rosal 12, 28040 Madrid (Spain); Garcia, M. [UNED, Power Engineering Department, C/Juan del Rosal 12, 28040 Madrid (Spain); Pampin, R. [F4E, Torres Diagonal Litoral B3, Barcelona (Spain); Sanz, J. [UNED, Power Engineering Department, C/Juan del Rosal 12, 28040 Madrid (Spain)

    2016-11-15

    Highlights: • Feasibility of manual maintenance activities in ITER port cell and port interspace. • Activation of relevant materials and components placed in the current ITER model. • Dominant radionuclides and pathways for shutdown dose rate in ITER. • Quality analysis of typically used EAF and TENDL activation libraries is performed. • EAF performance found as trustworthy with slight recommended improvements. - Abstract: This paper assesses the quality of the EAF-2007 and 2010 activation cross sections for relevant reactions in the determination of the Shutdown Dose Rate (SDDR) in the Port Cell (PC) and Port Interspace (PI) areas of ITER. For each of relevant ITER materials, dominant radionuclides responsible of SDDR and their production pathways are listed. This information comes from a review of the recent reports/papers about SDDR in ITER and own calculations. A total of 26 relevant pathways are found. The quality of these cross sections pathways is assessed following EAF validation procedure, and for those found as not validated last TENDL library versions have been investigated in order to check possible improvements when compared to EAF. The use of EAF libraries is found as trustworthy and it is recommended for the prediction of SDDR in the ITER PC and PI. However, 3 cross section reactions are considered for further improvement: Co59(n,2n)Co58, Cu63(n,g)Cu64 and Cr50(n,g)Cr51.

  13. 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.

  14. 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.

  15. Improvements for extending the time between maintenance periods for the Heidelberg ion beam therapy center (HIT) ion sources

    Energy Technology Data Exchange (ETDEWEB)

    Winkelmann, Tim, E-mail: tim.winkelmann@med.uni-heidelberg.de; Cee, Rainer; Haberer, Thomas; Naas, Bernd; Peters, Andreas; Schreiner, Jochen [Heidelberger Ionenstrahl-Therapie Centrum (HIT), D -69120 Heidelberg (Germany)

    2014-02-15

    The clinical operation at the Heidelberg Ion Beam Therapy Center (HIT) started in November 2009; since then more than 1600 patients have been treated. In a 24/7 operation scheme two 14.5 GHz electron cyclotron resonance ion sources are routinely used to produce protons and carbon ions. The modification of the low energy beam transport line and the integration of a third ion source into the therapy facility will be shown. In the last year we implemented a new extraction system at all three sources to enhance the lifetime of extraction parts and reduce preventive and corrective maintenance. The new four-electrode-design provides electron suppression as well as lower beam emittance. Unwanted beam sputtering effects which typically lead to contamination of the insulator ceramics and subsequent high-voltage break-downs are minimized by the beam guidance of the new extraction system. By this measure the service interval can be increased significantly. As a side effect, the beam emittance can be reduced allowing a less challenging working point for the ion sources without reducing the effective beam performance. This paper gives also an outlook to further enhancements at the HIT ion source testbench.

  16. Adalimumab for maintenance therapy for one year in Crohn's disease: results of a Latin American single-center observational study.

    Science.gov (United States)

    Kotze, Paulo Gustavo; Abou-Rejaile, Vinícius Rezende; Uiema, Luciana Aparecida; Olandoski, Marcia; Sartor, Maria Cristina; Miranda, Eron Fábio; Kotze, Lorete Maria da Silva; Saad-Hossne, Rogério

    2014-01-01

    Adalimumab is a fully-human antibody that inhibits TNF alpha, with a significant efficacy for long-term maintenance of remission. Studies with this agent in Latin American Crohn's disease patients are scarce. The objective of this study was to outline clinical remission rates after 12 months of adalimumab therapy for Crohn's disease patients. Retrospective, single-center, observational study of a Brazilian case series of Crohn's disease patients under adalimumab therapy. Variables analyzed: demographic data, Montreal classification, concomitant medication, remission rates after 1, 4, 6 and 12 months. Remission was defined as Harvey-Bradshaw Index ≤ 4, and non-responder-imputation and last-observation-carried-forward analysis were used. The influence of infliximab on remission rates was analyzed by Fischer and Chi-square tests (Panalysis. After 12 months, remission on patients with previous infliximab occurred in 69.23% as compared to 94.59% in infliximab-naïve patients (P = 0.033). Adalimumab was effective in maintaining clinical remission after 12 months of therapy, with an adequate safety profile, and was also more effective in infliximab naïve patients.

  17. El mantenimiento en la confiabilidad y disponibilidad de un sistema de generación de vapor // Maintenance on the reliability and availability of steam boiler systems

    Directory of Open Access Journals (Sweden)

    Mayra Troncoso-Fleitas

    2011-05-01

    Full Text Available El presente trabajo tiene como objetivo revelar y agrupar los principales hallazgos de seguridaddetectados en Sistemas de Generación de Vapor, SGV, que influyen en su confiabilidad ydisponibilidad y son causados por debilidades en la función mantenimiento. Los hallazgos han sidoidentificados mediante la aplicación de Técnicas de Identificación de Peligros, TIP, como Revisionesde Seguridad, Análisis HAZOP y Análisis Qué pasa si..?, entre otras metodologías y técnicasdisponibles, a más de una treintena de instalaciones donde los SGV han cumplido funciones tanto deapoyo a la producción como a los servicios. Agrupar y analizar estos hallazgos, problemas odesviaciones de seguridad han revelado que, independientemente del grado de cultura de seguridadque presente la instalación objeto de estudio, tienen un mismo origen y requieren de accionessimilares para su gestión.Palabras claves: mantenimiento, confiabilidad, disponibilidad, seguridad, caldera, generación de vapor.__________________________________________________________________AbstractThis paper has as objective to develop and to group the main findings of safety detected in SteamBoiler Systems that influence in its reliability and availability and they are caused by weaknesses inthe function maintenance. Findings have been identified by means of the application of HazardIdentification Techniques, HIT, like Safety Revision, HAZOP Analysis, What if..? Analysis and othersmethodologies and techniques available, applied to more than a thirty of where the Steam BoilerSystems have fulfilled functions in support to the production or services. Grouping and analyzingthese findings, problems or deviations of safety have revealed that, independently of the grade ofsafety culture presents in the facility, they have common causes and they require of similar actions fortheir management.Key words: maintenance, reliability, safety, availability, steam boilers.

  18. Reliability and validity study of Persian modified version of MUSIC (musculoskeletal intervention center – Norrtalje questionnaire

    Directory of Open Access Journals (Sweden)

    Jensen Irene

    2007-08-01

    Full Text Available Abstract Background Musculoskeletal disorders (MSDs are a major health problem in the world. Self-reported questionnaires are a known method for estimating the prevalence of MSDs among the population. One of the studies concerning MSDs and their relation to work-related physical and psychosocial factors, as well as non-work-related factors, is the MUSIC-Norrtalje study in Sweden. In this study, the research group developed a questionnaire, which has been validated during its development process and is now considered a well-known instrument. The aim of this study is to validate the Persian version of this questionnaire. Methods The first step was to establish two expert panel groups in Iran and Sweden. The Focus Group Discussion (FGD method was used to detect questionnaire face and content validity. To detect questionnaire reliability, we used the test-retest method. Results Except for two items, all other questions that respondents had problems with in the focus group (20 of 297, had unclear translations; the ambiguity was related to the stem of the questions and the predicted answers were clear for the participants. The concepts of 'household/spare time' and 'physical activity in the workplace' were not understood by the participants of FGD; this has been solved by adding further descriptions to these phrases in the translation. In the test-retest study, the reliability coefficient was relatively high in most items (only 5 items out of 297 had an ICC or kappa below 0.7. Conclusion The findings from the present study provide evidence that the Persian version of the MUSIC questionnaire is a reliable and valid instrument.

  19. RFA-based 589-nm guide star lasers for ESO VLT: a paradigm shift in performance, operational simplicity, reliability, and maintenance

    Science.gov (United States)

    Friedenauer, Axel; Karpov, Vladimir; Wei, Daoping; Hager, Manfred; Ernstberger, Bernhard; Clements, Wallace R. L.; Kaenders, Wilhelm G.

    2012-07-01

    Large telescopes equipped with adaptive optics require 20-25W CW 589-nm sources with emission linewidths of ~5 MHz. These Guide Star (GS) lasers should also be highly reliable and simple to operate and maintain for many years at the top of a mountain facility. Under contract from ESO, industrial partners TOPTICA and MPBC are nearing completion of the development of GS lasers for the ESO VLT, with delivery of the first of four units scheduled for December 2012. We report on the design and performance of the fully-engineered Pre-Production Unit (PPU), including system reliability/availability analysis, the successfully-concluded qualification testing, long-term component and system level tests and long-term maintenance and support planning. The chosen approach is based on ESO's patented narrow-band Raman Fiber Amplifier (EFRA) technology. A master oscillator signal from a linearly-polarized TOPTICA 20-mW, 1178-nm CW diode laser, with stabilized emission frequency and controllable linewidth up to a few MHz, is amplified in an MPBC polarization-maintaining (PM) RFA pumped by a high-power 1120-nm PM fiber laser. With efficient stimulated Brillouin scattering suppression, an unprecedented 40W of narrow-band RFA output has been obtained. This is then mode-matched into a resonant-cavity doubler with a free-spectral-range matching the sodium D2a to D2b separation, allowing simultaneous generation of an additional frequency component (D2b line) to re-pump the sodium atom electronic population. With this technique, the return flux can be increased without having to resort to electro-optical modulators and without the risk of introducing optical wave front distortions. The demonstrated output powers with doubling efficiencies >80% at 589 nm easily exceed the 20W design goal and require less than 700 W of electrical power. In summary, the fiber-based guide star lasers provide excellent beam quality and are modular, turn-key, maintenance-free, reliable, efficient, and ruggedized

  20. The Possible Effects of Methadone Maintenance Therapy on Erectile Dysfunction in Male Addicts Visiting MMT Centers of Rasht

    Directory of Open Access Journals (Sweden)

    Morteza Rahbar Taramsari

    2014-06-01

    Full Text Available Background: Methadone is considered a long-acting opioid agonist which is widely used in the treatment of drug addiction. It is believed that opioids can cause erectile dysfunction (ED by inhibiting gonadotropin and testosterone release. This study is aimed at defining the possible effects of conservative treatment with methadone on erectile dysfunction in the addicts. Methods: A total of 382 male addicts visiting methadone maintenance therapy (MMT centers in Rasht, Iran, during 2010 were enrolled in this study. International Index of Erectile Function (IIEF questionnaire and patients' profiles were the main means of collecting data on demographic information, methadone dose intake, and erectile function status before and after the two months of therapy with methadone. Erectile function status was defined by the total score from questions 1, 2, 3, 4, 5, and 15 of the questionnaire. The data was analyzed by X2, McNemer’s test, and paired t-test using SPSS software 18. Results: The mean age of patients was 37.6 ± 8.9 years (range: 18-72 years. Most of the patients were married (79.3% and they were citizens of Rasht (72.3%. The most frequent substances were opium (188 patients, 49.2% and crack (129 patients, 33.8%, respectively. Most of the patients received low dose methadone (286 patients, 74.9%. No significant relationship was indicated comparing the average scores of erectile function before and after taking methadone (18.53±6.978 vs. 19.03±5.819 (P=0.138. However, the severity of erectile dysfunction was significantly related to the methadone intake dose (P<0.001. Conclusion: Although MMT increases the frequency of erectile dysfunction, appropriate doses of methadone minimize this effect.

  1. Dukovany NPP maintenance management

    International Nuclear Information System (INIS)

    Siegel, F.

    2005-01-01

    Maintenance planning and management for the technological equipment of the Dukovany NPP are described. A Maintenance Control and Evaluation System has been developed and is in use to help manage the complex maintenance issue. Practical examples of outputs of the System, with a comprehensive use of the cost, reliability and safety related data, are presented. (author)

  2. Maintenance for the Millennium: Another Approach

    International Nuclear Information System (INIS)

    Sculthorpe, Barruy R.

    2002-01-01

    Nuclear units nationwide are struggling to increase plant reliability and availability while at the same time reduce their operating and maintenance costs. Some very costly investments have been made in programs such as Reliability Centered Maintenance [RCM]. Florida Power and Light's approach at the St. Lucie Nuclear Plant has taken a slightly different approach. Building on our knowledge of the RCM process and an already existing 'World Class' Predictive Maintenance Program, a 'Condition-Based' Maintenance Program that takes advantage of the RCM philosophy and our toolbox full of advanced and highly successful predictive maintenance technologies. These tools currently consist of vibration analysis, lubricant analysis (both physical property and wear metals analysis, thermographic analysis, motor current signature analysis, tribology and process parameter trending. All employed with the intent to evaluate a machines health. This machine health check allows the forecasting of future preventative maintenance [PM's] tasks and the revision of existing PM's to maximize machine performance and eliminate 'no-value-added' maintenance activities/costs. Within the last year, the Condition-Based Maintenance Program has produced a cost saving of approximately $1.5 million dollars. As the program matures, these cost savings will accumulate well into the millennium. (authors)

  3. Systematic maintenance analysis with decision support method and tool for optimizing maintenance programme

    International Nuclear Information System (INIS)

    Laakso, K.; Simola, K.; Dorrepaal, J.; Skogberg, P.

    1999-01-01

    This report describes an approach to evaluate the effectiveness of test and maintenance programs of technical systems used during several years. The method combines an analysis of the historical data on faults and repairs with an analysis of the history of periodic testing and preventive maintenance action programs. The application of the maintenance analysis from the methodological point of view in the reliability centered maintenance (RCM) project for Barsebaeck nuclear power plant is described. In order to limit the analysis resources, a method for ranking of objects for maintenance analysis is needed. Preliminary suggestions for changes in maintenance action programs are based on signals from simple maintenance indicators and qualitative analysis of underlying data on failures and maintenance. To facilitate generation of maintenance indicators, and make the maintenance analysis more efficient, a powerful and suitable data treatment tool is needed for analysis of the work order history. In the final maintenance decisions, additional decision criteria must be taken into account, and thus a more formal decision analysis is often needed for decision support. (au)

  4. Measuring the quality of patient-centered care: why patient-reported measures are critical to reliable assessment

    Directory of Open Access Journals (Sweden)

    Tzelepis F

    2015-06-01

    Full Text Available Flora Tzelepis, Robert W Sanson-Fisher, Alison C Zucca, Elizabeth A FradgleyPriority Research Centre for Health Behaviour, University of Newcastle and Hunter Medical Research Institute, Newcastle, NSW, AustraliaPurpose: The Institute of Medicine (IOM identified patient-centeredness as crucial to quality health care. The IOM endorsed six patient-centeredness dimensions that stipulated that care must be: respectful to patients’ values, preferences, and expressed needs; coordinated and integrated; provide information, communication, and education; ensure physical comfort; provide emotional support; and involve family and friends. Patient-reported measures examine the patient’s perspective and are essential to the accurate assessment of patient-centered care. This article’s objectives are to: 1 use the six IOM-endorsed patient-centeredness dimensions as a framework to outline why patient-reported measures are crucial to the reliable measurement of patient-centered care; and 2 to identify existing patient-reported measures that assess each patient-centered care dimension.Methods: For each IOM-endorsed patient-centeredness dimension, the published literature was searched to highlight the essential role of patients in assessing patient-centered care and informing quality improvement efforts. Existing literature was also searched to identify examples of patient-reported measures that assess each patient-centeredness dimension.Conclusion: Patient-reported measures are arguably the best way to measure patient-centeredness. For instance, patients are best positioned to determine whether care aligns with patient values, preferences, and needs and the Measure of Patient Preferences is an example of a patient-reported measure that does so. Furthermore, only the patient knows whether they received the level of information desired, and if information was understood and can be recalled. Patient-reported measures that examine information provision include

  5. Human Reliability Analysis. Applicability of the HRA-concept in maintenance shutdown; Analys av maensklig tillfoerlitlighet. HRA-begreppets tillaempbarhet vid revisionsavstaellning

    Energy Technology Data Exchange (ETDEWEB)

    Obenius, Aino (MTO Psykologi AB, Stockholm (SE))

    2007-08-15

    Probabilistic Safety Analysis (PSA) is performed for Swedish nuclear power plants in order to make predictions and improvements of system safety. The analysis of the Three Mile Island and Chernobyl accidents contributed to broaden the approach to nuclear power plant safety. A system perspective focusing on the interaction between aspects of Man, Technology and Organization (MTO) emerged in addition to the development of Human Factors knowledge. To take the human influence on the technical system into consideration when performing PSAs, a Human Reliability Analysis (HRA) is performed. PSA is performed for different stages and plant operating states, and the current state of Swedish analyses is Low power and Shutdown (LPSD), also called Shutdown PSA (SPSA). The purpose of this master's thesis is to describe methods and basic models used when analysing human reliability for the LPSD state. The following questions are at issue: 1. How can the LPSD state be characterised and defined? 2. What is important to take into consideration when performing a LPSD HRA? 3. How can human behaviour be modelled for a LPSD risk analysis? 4. According to available empirical material, how are the questions above treated in performed analysis of human operation during LPSD? 5. How does the result of the questions above affect the way methods for analysis of LPSD could and/or should be developed? The procedure of this project has mainly consisted of literature studies of available theory for modelling of human behaviour and risk analysis of the LPSD state. This study regards analysis of planned outages when maintenance, fuel change, tests and inspections are performed. The outage period is characterised by planned maintenance activities performed in rotating 3-shifts, around the clock, as well as many of the persons performing work tasks on the plant being external contractors. The working conditions are characterised by stress due to heat, radiation and physically demanding or

  6. Good practices for cost effective maintenance of nuclear power plants

    International Nuclear Information System (INIS)

    1997-02-01

    This publication is organized around five areas that were identified by the utilities and government organizations who contributed to this report as most important to them. They are: Increasing production through maintenance activities related to improved plant material condition, reduced duration of planned outages, use of on-line maintenance and reduced frequency of forced outages; reducing workload through avoiding unnecessary regulatory burden and using reliability centered maintenance and condition monitoring; improving maintenance processes through better planning and scheduling, use of information management systems, graduated work controls, and appropriate post-maintenance testing; improving productivity through better teamwork, greater sharing of resources, and better radiation management associated with maintenance; measuring performance of maintenance activities through such tools as performance measures and benchmarking. Figs, tabs

  7. Derivation of centers and axes of rotation for wrist and fingers in a hand kinematic model: methods and reliability results.

    Science.gov (United States)

    Cerveri, P; Lopomo, N; Pedotti, A; Ferrigno, G

    2005-03-01

    In the field of 3D reconstruction of human motion from video, model-based techniques have been proposed to increase the estimation accuracy and the degree of automation. The feasibility of this approach is strictly connected with the adopted biomechanical model. Particularly, the representation of the kinematic chain and the assessment of the corresponding parameters play a relevant role for the success of the motion assessment. In this paper, the focus is on the determination of the kinematic parameters of a general hand skeleton model using surface measurements. A novel method that integrates nonrigid sphere fitting and evolutionary optimization is proposed to estimate the centers and the functional axes of rotation of the skeletal joints. The reliability of the technique is tested using real movement data and simulated motions with known ground truth 3D measurement noise and different ranges of motion (RoM). With respect to standard nonrigid sphere fitting techniques, the proposed method performs 10-50% better in the best condition (very low noise and wide RoM) and over 100% better with physiological artifacts and RoM. Repeatability in the range of a couple of millimeters, on the localization of the centers of rotation, and in the range of one degree, on the axis directions is obtained from real data experiments.

  8. Regulatory surveillance of safety related maintenance at nuclear power plants. Report of a technical committee meeting

    International Nuclear Information System (INIS)

    1997-08-01

    The operational safety and reliability of a nuclear power plant as well as its availability for electricity generation depend on, among other things, its maintenance programme. Regulatory bodies therefore have considerable interest in maintenance activities. There are several approaches to maintenance, i.e. reliability centered maintenance or risk focused maintenance, aimed at optimizing maintenance by focusing on important components or systems. These approaches may result in significant changes to maintenance activities and therefore have to be considered for regulatory acceptance. In order to review and discuss the status of maintenance regulation in participating countries, the IAEA convened a Technical Committee Meeting on Regulatory Oversight of Maintenance Activities at Nuclear Power Plants in Vienna from 9 to 13 October 1995. The meeting was attended by 16 experts from 11 countries. In addition to the consideration of papers that were presented and which are reproduced here, extensive group and panel discussions took place during the meeting. These covered three main topics: general features and basic characteristics of maintenance regulation, regulatory acceptance of maintenance optimization and use of PSA for maintenance optimization. The discussion are summarized in Section 2. Section 3 discusses the following three additional topics: regulatory involvement in the maintenance programme, modifications to the maintenance programme and personnel related aspects of maintenance. The conclusions are presented in Section 4. Figs, tabs

  9. Learner-Centered Instruction (LCI): Volume IV, The Simulated Maintenance Task Environment (SMTE): A Job Specific Simulator.

    Science.gov (United States)

    Rifkin, Kenneth I.; And Others

    The purpose of the simulated maintenance task environment is to provide a means for training and job performance testing of the flight line weapon control systems mechanic/technician for the F-111A aircraft. It provides practice in flight line equipment checkout, troubleshooting, and removal and replacement of line replaceable units in the…

  10. Improvement of the preventive maintenance program of an emergency diesel generator set

    International Nuclear Information System (INIS)

    Jacquot, J.P.; Meuwisse, C.; Cailleaux, J.P.

    1995-01-01

    An exhaustive Reliability Centered Maintenance (RCM) analysis was performed of the emergency diesel generator sets in Electricite de France 900-MW nuclear power plants. The first part of this paper describes the Reliability Centered Maintenance approach, including the functional breakdown, complete analysis of operation feedback and safety assessment of the risk induced by functional diesel failures. The second part shows how this kind of RCM analysis can be used to improve the efficiency of periodic tests of the machine, and more generally, the efficiency of condition-directed maintenance tasks. The underlying objective is to minimize risk and aging of the machine

  11. Preventive maintenance: optimization of time - based discard decisions at the bruce nuclear generating station

    International Nuclear Information System (INIS)

    Doyle, E.K.; Jardine, A.K.S.

    2001-01-01

    The use of various maintenance optimization techniques at Bruce has lead to cost effective preventive maintenance applications for complex systems. As previously reported at ICONE 6 in New Orleans, 1996, several innovative practices reduced Reliability Centered Maintenance costs while maintaining the accuracy of the analysis. The optimization strategy has undergone further evolution and at the present an Integrated Maintenance Program (IMP) is in place where an Expert Panel consisting of all players/experts proceed through each system in a disciplined fashion and reach agreement on all items under a rigorous time frame. It is well known that there are essentially 3 maintenance based actions that can flow from a Maintenance Optimization Analysis: condition based maintenance, time based maintenance and time based discard. The present effort deals with time based discard decisions. Maintenance data from the Remote On-Power Fuel Changing System was used. (author)

  12. A genetic algorithm solution for a nuclear power plant risk-cost maintenance model

    International Nuclear Information System (INIS)

    Tong Jiejuan; Mao Dingyuan; Xue Dazhi

    2004-01-01

    Reliability Centered Maintenance (RCM) is one of the popular maintenance optimization methods according to certain kinds of priorities. Traditional RCM usually analyzes and optimizes the maintenance strategy from the viewpoint of component instead of the whole maintenance program impact. Research presented in this paper is a pilot study using PSA techniques in RCM. How to reflect the effect on component unavailability by the maintenance activities such as surveillance testing and preventive maintenance in PSA model is discussed firstly. Based on the discussion, a maintenance risk-cost model is established for global maintenance optimization in a nuclear power plant, and a genetic algorithm (GA) is applied to solve such a model to get the global optimized maintenance strategy. Finally, the result got from a simple test case based on a risk-cost model consisting of 10 components is presented

  13. Probability distribution of machining center failures

    International Nuclear Information System (INIS)

    Jia Yazhou; Wang Molin; Jia Zhixin

    1995-01-01

    Through field tracing research for 24 Chinese cutter-changeable CNC machine tools (machining centers) over a period of one year, a database of operation and maintenance for machining centers was built, the failure data was fitted to the Weibull distribution and the exponential distribution, the effectiveness was tested, and the failure distribution pattern of machining centers was found. Finally, the reliability characterizations for machining centers are proposed

  14. 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

  15. Advances in safety related maintenance

    International Nuclear Information System (INIS)

    2000-03-01

    The maintenance of systems, structures and components in nuclear power plants (NPPs) plays an important role in assuring their safe and reliable operation. Worldwide, NPP maintenance managers are seeking to reduce overall maintenance costs while maintaining or improving the levels of safety and reliability. Thus, the issue of NPP maintenance is one of the most challenging aspects of nuclear power generation. There is a direct relation between safety and maintenance. While maintenance alone (apart from modifications) will not make a plant safer than its original design, deficient maintenance may result in either an increased number of transients and challenges to safety systems or reduced reliability and availability of safety systems. The confidence that NPP structures, systems and components will function as designed is ultimately based on programmes which monitor both their reliability and availability to perform their intended safety function. Because of this, approaches to monitor the effectiveness of maintenance are also necessary. An effective maintenance programme ensures that there is a balance between the improvement in component reliability to be achieved and the loss of component function due to maintenance downtime. This implies that the safety level of an NPP should not be adversely affected by maintenance performed during operation. The nuclear industry widely acknowledges the importance of maintenance in NPP safety and operation and therefore devotes great efforts to develop techniques, methods and tools to aid in maintenance planning, follow-up and optimization, and in assuring the effectiveness of maintenance

  16. Safety of nuclear operation and maintenance

    International Nuclear Information System (INIS)

    Mori, M.; Nitta, T.; Sakai, K.

    1994-01-01

    The Kansai Electric Power Co. Inc.(Kansai EPC) aims to pursue a high quality and highly reliable operation in nuclear power generation in order to ensure safety by reducing the risk of accidents and win the confidence from the society and the public. It is emphasised that in order to realize this aim manufacturers and contractors cooperate with each other in performing high quality maintenance through plant lifetime maintenance system. TQC (Total Quality Control) activity enhances the motivation for each individual to have a quality-oriented mind and cultivate the safety culture. Under the lifetime employment practice, Kansai EPC and maintenance contractors can conduct systematic education and training, and the Maintenance Training Center helps to make it effective. 6 figs

  17. Prediction of attendance at fitness center: a comparison between the theory of planned behavior, the social cognitive theory, and the physical activity maintenance theory.

    Science.gov (United States)

    Jekauc, Darko; Völkle, Manuel; Wagner, Matthias O; Mess, Filip; Reiner, Miriam; Renner, Britta

    2015-01-01

    In the processes of physical activity (PA) maintenance specific predictors are effective, which differ from other stages of PA development. Recently, Physical Activity Maintenance Theory (PAMT) was specifically developed for prediction of PA maintenance. The aim of the present study was to evaluate the predictability of the future behavior by the PAMT and compare it with the Theory of Planned Behavior (TPB) and Social Cognitive Theory (SCT). Participation rate in a fitness center was observed for 101 college students (53 female) aged between 19 and 32 years (M = 23.6; SD = 2.9) over 20 weeks using a magnetic card. In order to predict the pattern of participation TPB, SCT and PAMT were used. A latent class zero-inflated Poisson growth curve analysis identified two participation patterns: regular attenders and intermittent exercisers. SCT showed the highest predictive power followed by PAMT and TPB. Impeding aspects as life stress and barriers were the strongest predictors suggesting that overcoming barriers might be an important aspect for working out on a regular basis. Self-efficacy, perceived behavioral control, and social support could also significantly differentiate between the participation patterns.

  18. Modern electronic maintenance principles

    CERN Document Server

    Garland, DJ

    2013-01-01

    Modern Electronic Maintenance Principles reviews the principles of maintaining modern, complex electronic equipment, with emphasis on preventive and corrective maintenance. Unfamiliar subjects such as the half-split method of fault location, functional diagrams, and fault finding guides are explained. This book consists of 12 chapters and begins by stressing the need for maintenance principles and discussing the problem of complexity as well as the requirements for a maintenance technician. The next chapter deals with the connection between reliability and maintenance and defines the terms fai

  19. Maintenance work management system

    International Nuclear Information System (INIS)

    Kanai, T.; Takahashi, Y.; Takahashi, K.; Nishino, M.; Takeshige, R.

    2000-01-01

    The maintenance work management system supports the efficient drawing up of various documents for the maintenance work at nuclear power stations and the speeding up of the permission procedure. In addition, it improves the quality assurance of the safety and reliability of the maintenance work. Key merits of the system are: 1. Efficiently drawing up various documents for the maintenance work by using the stored data for the previous maintenance work and the pipe and instrument diagram (P and ID) data. 2. Supporting the management work for the completion of maintenance work safety by using the isolation information stored on the computer system. 3. Speeding up the permission procedure by electronic mail and electronic permission. 4. Displaying additional information such as the specifications of equipment, maintenance result, and maintenance plan by linking up with the database of another system. 5. Reducing the cost of hardware devices by using client/server network configurations of personal computers and a personal computer server. (author)

  20. Experts' meeting: Maintenance '83

    International Nuclear Information System (INIS)

    1983-01-01

    The brochure presents, in full wording, 20 papers read at the experts' meeting ''Maintenance '83'' in Wiesbaden. Most of the papers discuss reliability data (acquisition, evaluation, processing) of nearly all fields of industry. (RW) [de

  1. Reliability and Repetition Effect of the Center of Pressure and Kinematics Parameters That Characterize Trunk Postural Control During Unstable Sitting Test.

    Science.gov (United States)

    Barbado, David; Moreside, Janice; Vera-Garcia, Francisco J

    2017-03-01

    Although unstable seat methodology has been used to assess trunk postural control, the reliability of the variables that characterize it remains unclear. To analyze reliability and learning effect of center of pressure (COP) and kinematic parameters that characterize trunk postural control performance in unstable seating. The relationships between kinematic and COP parameters also were explored. Test-retest reliability design. Biomechanics laboratory setting. Twenty-three healthy male subjects. Participants volunteered to perform 3 sessions at 1-week intervals, each consisting of five 70-second balancing trials. A force platform and a motion capture system were used to measure COP and pelvis, thorax, and spine displacements. Reliability was assessed through standard error of measurement (SEM) and intraclass correlation coefficients (ICC 2,1 ) using 3 methods: (1) comparing the last trial score of each day; (2) comparing the best trial score of each day; and (3) calculating the average of the three last trial scores of each day. Standard deviation and mean velocity were calculated to assess balance performance. Although analyses of variance showed some differences in balance performance between days, these differences were not significant between days 2 and 3. Best result and average methods showed the greatest reliability. Mean velocity of the COP showed high reliability (0.71 reliability (0.37 reliability using the average method (0.62 reliability than kinematics ones. Specifically, mean velocity of COP showed the highest test-retest reliability, especially for the average and best methods. Although correlations between COP and mean joint angular velocity were high, the few relationships between COP and kinematic standard deviation suggest different postural behavior can lead to a similar balance performance during an unstable sitting protocol. III. Copyright © 2017 American Academy of Physical Medicine and Rehabilitation. Published by Elsevier Inc. All rights

  2. JRR-3 maintenance program utilizing accumulated maintenance data

    International Nuclear Information System (INIS)

    Izumo, Hironobu; Kato, Tomoaki; Kinase, Masami; Torii, Yoshiya; Murayama, Yoji

    2007-07-01

    JRR-3(Japan Research Reactor No.3) has been operated for more than 15 years after the modification, without significant troubles by carrying out maintenance such as the preventive maintenance (mainly time-based maintenance) for the safety-grade equipments and the breakdown maintenance for the non-safety-grade equipments. Unscheduled shutdowns causes by aged non-safety-grade equipments have been increasing, and the resources such as budgets have been decreasing year by year. In this situation, JRR-3 maintenance program was reviewed about safety, reliability and economic efficiency. This report offers the policy of the maintenance review and the future direction of maintenance programs. (author)

  3. Optimization of maintenance programme at Daya Bay Nuclear Power Station based on RCM analysis results

    International Nuclear Information System (INIS)

    Liu Min

    2003-01-01

    This paper begins with an introduction to Guangdong Daya Bay Nuclear Power Station (GNPS) and gives a simple introduction to the operations and maintenance documentation system at GNPS. It then will review the maintenance program guidelines base and the associated problems prior to the application of reliability centered maintenance (RCM). How RCM was implemented at GNPS, how the results of RCM analysis were used to optimize the maintenance program and test program, and what is the interface between RCM and the existing maintenance program will be shown. Next, it will show the successful implementation of RCM at GNPS resulted in the following changes: A new understanding of equipment failure challenges operations and maintenance beliefs, maintenance concepts undergo a large change, maintenance program and periodic testing program are continuously modified and optimized, new on-condition maintenance technologies are introduced, non-productive scheduled overhauls are discarded, maintenance costs are effectively controlled, maintenance appropriateness has improved, management of hidden failures is more effective and timely. It will show the benefit of greater equipment reliability brought about by all of these changes, which in turn increases the reliability and safety of the entire power station. (author)

  4. Knowledge based maintenance

    Energy Technology Data Exchange (ETDEWEB)

    Sturm, A [Hamburgische Electacitaets-Werke AG Hamburg (Germany)

    1998-12-31

    The establishment of maintenance strategies is of crucial significance for the reliability of a plant and the economic efficiency of maintenance measures. Knowledge about the condition of components and plants from the technical and business management point of view therefore becomes one of the fundamental questions and the key to efficient management and maintenance. A new way to determine the maintenance strategy can be called: Knowledge Based Maintenance. A simple method for determining strategies while taking the technical condition of the components of the production process into account to the greatest possible degree which can be shown. A software with an algorithm for Knowledge Based Maintenance leads the user during complex work to the determination of maintenance strategies for this complex plant components. (orig.)

  5. Knowledge based maintenance

    Energy Technology Data Exchange (ETDEWEB)

    Sturm, A. [Hamburgische Electacitaets-Werke AG Hamburg (Germany)

    1997-12-31

    The establishment of maintenance strategies is of crucial significance for the reliability of a plant and the economic efficiency of maintenance measures. Knowledge about the condition of components and plants from the technical and business management point of view therefore becomes one of the fundamental questions and the key to efficient management and maintenance. A new way to determine the maintenance strategy can be called: Knowledge Based Maintenance. A simple method for determining strategies while taking the technical condition of the components of the production process into account to the greatest possible degree which can be shown. A software with an algorithm for Knowledge Based Maintenance leads the user during complex work to the determination of maintenance strategies for this complex plant components. (orig.)

  6. 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.

  7. Prevalence and associated factors of hepatitis C virus infection among renal disease patients on maintenance hemodialysis in three health centers in Aden, Yemen: A cross sectional study

    Directory of Open Access Journals (Sweden)

    Khadija Aman

    2015-01-01

    Full Text Available We aimed to assess the prevalence and factors associated with positive anti-hepatitis C virus (HCV antibodies among patients on maintenance hemodialysis (HD in three centers in Aden, Yemen. The data from 219 patients and their records over the period between 2000-2013, was extracted and analyzed. The mean ± SD age of the patients was 47.08 ± 13.9 years; 74.4% of them were married and 14.6% were employed. The prevalence of validated anti-HCV-positive cases was 40.2% (95%CI 33.64%-46.73%. The mean ± SD duration on HD of all the patients was 35.09 ± 38 months. On bivariate analysis, the duration on HD and attending more than one center for HD associated significantly with anti-HCV positivity (P <0.05. On multivariate fully adjusted Poisson regression modelling, controlled for age, Patients attending more than one center and those who underwent HD for longer durations were more likely to be positive for anti- HCV antibodies [P = 0.004, adjusted prevalence rate ratio (APRR = 1.87, 95% confidence interval (CI: 1.22-2.88; P = 0.0005, APRR = 1.01, 95% CI: 1.00-1.02. In this study sample, the prevalence of HCV was significant. Patients attending more than one center and those who underwent HD for longer durations were found to be more likely to contract HCV. Enhancing existing infection control measures and allocating more resources to HD centers therefore warrants consideration.

  8. Prevalence and associated factors of hepatitis C virus infection among renal disease patients on maintenance hemodialysis in three health centers in Aden, Yemen: a cross sectional study.

    Science.gov (United States)

    Aman, Khadija; Al-Dubai, Sami AbdoRadman; Aman, Reema; Hawash, Aamenah; Alshagga, Mustafa; Kassim, Saba

    2015-03-01

    We aimed to assess the prevalence and factors associated with positive anti-hepatitis C virus (HCV) antibodies among patients on maintenance hemodialysis (HD) in three centers in Aden, Yemen. The data from 219 patients and their records over the period between 2000-2013, was extracted and analyzed. The mean ± SD age of the patients was 47.08 ± 13.9 years; 74.4% of them were married and 14.6% were employed. The prevalence of validated anti-HCV-positive cases was 40.2% (95%CI 33.64%-46.73%). The mean ± SD duration on HD of all the patients was 35.09 ± 38 months. On bivariate analysis, the duration on HD and attending more than one center for HD associated significantly with anti-HCV positivity (P <0.05). On multivariate fully adjusted Poisson regression modelling, controlled for age, Patients attending more than one center and those who underwent HD for longer durations were more likely to be positive for anti- HCV antibodies [P = 0.004, adjusted prevalence rate ratio (APRR) = 1.87, 95% confidence interval (CI): 1.22-2.88; P = 0.0005, APRR = 1.01, 95% CI: 1.00-1.02. In this study sample, the prevalence of HCV was significant. Patients attending more than one center and those who underwent HD for longer durations were found to be more likely to contract HCV. Enhancing existing infection control measures and allocating more resources to HD centers therefore warrants consideration.

  9. Parameter Estimation of a Reliability Model of Demand-Caused and Standby-Related Failures of Safety Components Exposed to Degradation by Demand Stress and Ageing That Undergo Imperfect Maintenance

    Directory of Open Access Journals (Sweden)

    S. Martorell

    2017-01-01

    Full Text Available One can find many reliability, availability, and maintainability (RAM models proposed in the literature. However, such models become more complex day after day, as there is an attempt to capture equipment performance in a more realistic way, such as, explicitly addressing the effect of component ageing and degradation, surveillance activities, and corrective and preventive maintenance policies. Then, there is a need to fit the best model to real data by estimating the model parameters using an appropriate tool. This problem is not easy to solve in some cases since the number of parameters is large and the available data is scarce. This paper considers two main failure models commonly adopted to represent the probability of failure on demand (PFD of safety equipment: (1 by demand-caused and (2 standby-related failures. It proposes a maximum likelihood estimation (MLE approach for parameter estimation of a reliability model of demand-caused and standby-related failures of safety components exposed to degradation by demand stress and ageing that undergo imperfect maintenance. The case study considers real failure, test, and maintenance data for a typical motor-operated valve in a nuclear power plant. The results of the parameters estimation and the adoption of the best model are discussed.

  10. Contingent post-closure plan, hazardous waste management units at selected maintenance facilities, US Army National Training Center, Fort Irwin, California

    International Nuclear Information System (INIS)

    1992-01-01

    The National Training Center (NTC) at Fort Irwin, California, is a US Army training installation that provides tactical experience for battalion/task forces and squadrons in a mid- to high-intensity combat scenario. Through joint exercises with US Air Force and other services, the NTC also provides a data source for improvements of training doctrines, organization, and equipment. To meet the training and operational needs of the NTC, several maintenance facilities provide general and direct support for mechanical devices, equipment, and vehicles. Maintenance products used at these facilities include fuels, petroleum-based oils, lubricating grease, various degreasing solvents, antifreeze (ethylene glycol), transmission fluid, brake fluid, and hydraulic oil. Used or spent petroleum-based products generated at the maintenance facilities are temporarily accumulated in underground storage tanks (USTs), collected by the NTC hazardous waste management contractor (HAZCO), and stored at the Petroleum, Oil, and Lubricant (POL) Storage Facility, Building 630, until shipped off site to be recovered, reused, and/or reclaimed. Spent degreasing solvents and other hazardous wastes are containerized and stored on-base for up to 90 days at the NTC's Hazardous Waste Storage Facility, Building 703. The US Environmental Protection Agency (EPA) performed an inspection and reviewed the hazardous waste management operations of the NTC. Inspections indicated that the NTC had violated one or more requirements of Subtitle C of the Resource Conservation and Recovery Act (RCRA) and as a result of these violations was issued a Notice of Noncompliance, Notice of Necessity for Conference, and Proposed Compliance Schedule (NON) dated October 13, 1989. The following post-closure plan is the compliance-based approach for the NTC to respond to the regulatory violations cited in the NON

  11. A survey of research projects in maintenance optimization for Electricite de France power plants

    International Nuclear Information System (INIS)

    Jacquot, J.P.

    1996-01-01

    Six years ago, Electricite de France launched a Reliability Centered Maintenance (RCM) pilot project to optimize preventive maintenance for its nuclear power plants. After a feasibility study, a Reliability Centered Maintenance (RCM) method was standardized. It is now applied on a large scale to the 50 EDF nuclear units. A RCM workstation based on this standardized method has been developed and is now used in each plant. In the next step, the author will consider whether a risk based approach can be included in this RCM process in order to analyze critical passive components such as pipes and supports. Considering the potential advantages of these optimization techniques, a dedicated process has been also developed for maintenance of future plants, gas turbines, or nuclear units. For these future plants, a Logistic Support Analysis (LSA) will be added to the RCM process to globally evaluate availability, safety and maintenance costs. This paper will present a survey of these different developments of methods and tools

  12. Overview of maintenance principles and regulatory supervision of maintenance activities at nuclear power plants in Slovakia

    International Nuclear Information System (INIS)

    Rohar, S.; Cepcek, S.

    1997-01-01

    The maintenance represents one of the most important tools to ensure safe and reliable operation of nuclear power plants. The emphasis of Nuclear Regulatory Authority of the Slovak Republic to the maintenance issue is expressed by requirements in the regulations. The current practice of maintenance management in operated nuclear power plants in Slovak Republic is presented. Main aspects of maintenance, as maintenance programme, organization of maintenance, responsibilities for maintenance are described. Activities of nuclear regulatory authority in maintenance process are presented too. (author)

  13. Industrial Maintenance Strategies

    International Nuclear Information System (INIS)

    Sajjad Akbar

    2006-01-01

    Industrial plants have become more complex due to technological advancement. This has made the task of maintenance more difficult. The maintenance costs in terms of resources and downtime loss are so high that maintenance function has become a critical factor in a plant's profitability. Industry should devote as much forethought to the management of maintenance function as to production. Maintenance has grown from an art to a precise, technical engineering science. Planning, organizing scheduling and control of maintenance using modern techniques pays dividends in the form of reduced costs and increased reliability. The magnitude and the dimension of maintenance have multiplied due to development in the engineering technologies. Production cost and capacities are directly affected by the breakdown time. Total operating cost including the maintenance cost plays an important role in replacement dimension. The integrated system approach would bring forth the desired results of high maintenance standards. The standards once achieved and sustained, would add to the reliability of the plan and relieve heavy stresses and strains on the engineering logistic support. (author)

  14. An approach to integrating surveillance and maintenance tasks to prevent the dominant failure causes of critical components

    International Nuclear Information System (INIS)

    Martorell, S.; Munoz, A.; Serradell, V.

    1995-01-01

    Surveillance requirements and maintenance activities in a nuclear power plant aim to preserve components' inherent reliability. Up to now, predictive and preventive maintenance mainly concerned plant staff, but the US Nuclear Regulatory Commission Maintenance Rule released in July 1991 will have significant impact on how nuclear power plants perform and document this maintenance. Reliability Centered Maintenance (RCM) is a systematic methodology to establish maintenance tasks for critical components in plant with a high degree of compliance with the goals of the Rule. RCM pursues the identification of applicable and efficient tasks to prevent these components from developing their dominant failure causes, and, in turn, towards achieving proper levels of components availability with low cost. In this paper, we present an approach for identifying the most suitable set of tasks to achieve this goal, which involves the integration of maintenance activities and surveillance requirements for each critical component based on the unavailability and cost associated with each individual task which is performed on it

  15. Methods and tools in development in the field of maintenance; Methodes et outils pour la maintenance en cours de developpement

    Energy Technology Data Exchange (ETDEWEB)

    Le Reverend, D.; Tortolano, M. [Electricite de France (EDF/RD), 78 - Chatou (France); Leniaud, F. [Electricite de France (EDF), Div. Production Nuleaire, 93 - Saint-Denis (France)

    2004-07-01

    This article is dedicated to the maintenance strategy followed by EDF for its nuclear power plants. This strategy is based on the American method RCM (reliability centered method) that has been extended to passive components such as structures and relies on 4 axis. The first axis can be defined as the optimization of maintenance with regard to safety, outage and costs. The aim is to set the border between preventive maintenance and remedial maintenance. The second axis is the condition based maintenance that is the maintenance action that is triggered by the real state of the equipment. This type of maintenance implies the search for reliable and accurate diagnostics. The third axis is the design of simulation and planning tools required for the management of the moving of tools, machinery and spare-parts on a maintenance work site. The fourth axis is the design of tools able to repair some important equipment, this way may be a valid alternative to the replacement of equipment in terms of cost and outage time. (A.C.)

  16. Framework for Maintenance Planning

    DEFF Research Database (Denmark)

    Soares, C. Guedes; Duarte, J. Caldeira; Garbatov, Y.

    2010-01-01

    the design and during the whole life span of operational use, within an integrated framework founded on risk and reliability based techniques. The document addresses designers, decision makers and professionals responsible for or involved in establishing maintenance plans. The purpose of this document......The present document presents a framework for maintenance planning. Maintenance plays a fundamental role in counteracting degradation effects, which are present in all infrastructure and industrial products. Therefore, maintenance planning is a very critical aspect to consider both during...... is to present maintenance as an integrated approach that needs to be planned, designed, engineered, and controlled by proper qualitative and quantitative techniques. This document outlines the basic premises for maintenance planning and provides the general philosophies that can be followed and points to a best...

  17. Reliability Block Diagram (RBD) Analysis of NASA Dryden Flight Research Center (DFRC) Flight Termination System and Power Supply

    Science.gov (United States)

    Morehouse, Dennis V.

    2006-01-01

    In order to perform public risk analyses for vehicles containing Flight Termination Systems (FTS), it is necessary for the analyst to know the reliability of each of the components of the FTS. These systems are typically divided into two segments; a transmitter system and associated equipment, typically in a ground station or on a support aircraft, and a receiver system and associated equipment on the target vehicle. This analysis attempts to analyze the reliability of the NASA DFRC flight termination system ground transmitter segment for use in the larger risk analysis and to compare the results against two established Department of Defense availability standards for such equipment.

  18. Remote assembly and maintenance of fusion reactors

    International Nuclear Information System (INIS)

    Becquet, M.C.; Farfaletti-Casali, F.

    1991-01-01

    This paper intend to present the state of the art in the field of remote assembly and maintenance, including system analysis design and operation for controlled fusion device such as JET, and the next NET and ITER reactors. The operational constraints of fusion reactors with respect to temperature, radiations dose rates and cumulated doses are considered with the resulting design requirements. Concepts like articulated boom, in-vessel vehicle and blanket handling device are presented. The close relations between computer simulations and experimental validation of those concepts are emphasized to ensure reliability of the operational behavior. Mockups and prototypes in reduced and full scale, as operating machines are described to illustrate the progress in remote operations for fusion reactors. The developments achieved at the Institute for System Engineering and Informatics of the Joint Research Center, in the field of remote blanket maintenance, reliability assessment of RH systems and remote cut and welding of lips joints are considered. (author)

  19. Validity and reliability of the Center for Epidemiologic Studies-Depression scale on Colombians adolescent students Validez y confiabilidad de la escala del Center for Epidemiologic Studies-Depression en estudiantes adolescentes de Colombia

    OpenAIRE

    José Fidel Latorre; Álvaro Andrés Navarro-Mancilla; Mauricio Escobar; Jorge Augusto Franco; Paul Anthony Camacho; Germán Eduardo Rueda-Jaimes

    2009-01-01

    Introduction. Major depressive disorder is the second major cause of adolescent psychological incapacitation in Latin-America. However, scales for detecting these disorders have not been validated for screening adolescents in Colombia.
    Objective. The validity and reliability of a Spanish translation of the Center for Epidemiologic Studies (CES-D)-Depression scale was assessed in adolescent students.
    Materials and methods. A validation study for a diagnostic scale was per...

  20. Operations and maintenance - Safety challenges

    Energy Technology Data Exchange (ETDEWEB)

    Nielsen, Liv [Oljedirektoratet, Stavanger (Norway)

    1999-07-01

    With the unsteady oil prices and the possible consequences of the deregulation of the European energy markets one may expect further optimization of operating and maintenance costs. One may also expect extended use of various risk-based optimization techniques such as RCM (Reliability Centered Maintenance) and RBI (Risk Based Inspection). This presentation addresses the need for further research and development in this area. Maintenance work is necessary, but it can also create risk. The accident statistics show many examples of this. The Norwegian petroleum industry's ability to learn from previous incidents is questioned. Maintenance staff must be well trained and possess the necessary routines. Technical documentation must be updated. Uncertainties with respect to future oil and gas prices combined with the effect of the deregulation of the European energy markets will lead to even more focus on cost-effective operations and maintenance. The need for long-term research and development is stressed. Risk based techniques such as RCM and RBI are extensively used in the defence industry and the nuclear industry, but applying them to the petroleum industry requires improved risk models. Ageing effects such as corrosion, erosion, fatigue etc. can be expected, but the capability to predict, monitor and control them should be improved. At present, not even the most sophisticated risk analysis can model ageing effects. The importance of efficient use of information technology (IT) is stressed. Improving the product quality and safety often requires new technology and so research and development is important. Close cooperation with the industry is required.

  1. 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.

  2. Student-Centered Reliability, Concurrent Validity and Instructional Sensitivity in Scoring of Students' Concept Maps in a University Science Laboratory

    Science.gov (United States)

    Kaya, Osman Nafiz; Kilic, Ziya

    2004-01-01

    Student-centered approach of scoring the concept maps consisted of three elements namely symbol system, individual portfolio and scoring scheme. We scored student-constructed concept maps based on 5 concept map criteria: validity of concepts, adequacy of propositions, significance of cross-links, relevancy of examples, and interconnectedness. With…

  3. Breaker Maintenance: Volume 3, Molded-Case circuit breakers

    International Nuclear Information System (INIS)

    Davis, E.L.; Funk, D.L.

    1991-09-01

    Modeled-case circuit breakers (MCCBs) provide power and circuit protection in nuclear plant electrical distribution systems. Thus, their proper operation is essential to the safe and reliable operation of plant electrical distribution systems. This guide for both nuclear and non-nuclear power generating facilities will help improve the maintenance and reliability of MCCBs. The authors developed this guide to establish a working-level understanding of hardware performance trends, reliability, and failure modes from which maintenance practices could be specified. The first step in preparing this guide was an in-depth review of available operating experience and failure data, which was obtained from nuclear information sources such as EPRI's Nuclear Maintenance Applications Center. In addition, they evaluated some nonnuclear reliability data. Next, they investigated current industry practices, including a review of manufacturer's recommendations and numerous industry standards. Finally, they used the collective information to develop programmatic recommendations and, where appropriate, detailed inspection and test guidance. This guide offers many recommendations applicable to MCCB maintenance, such as an engineering description of MCCBs and their operation; an overview of reliability and failure data; programmatic recommendations, including inspection and test periodicity; detailed inspection and test guidance; and corrective maintenance recommendations. Supplementary information includes an overview of industry standards, a discussion of regulatory issues, and sample data sheets. An evaluation of operating experience indicates that a maintenance program need not be overly complicated to detect the predominant failure modes associated with MCCBs. Those implementating an MCCB maintenance and testing program, however, must recognize the inherent limitations associated with field-testing of these devices. 42 refs., 17 figs., 7 tabs

  4. 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

  5. ADALIMUMAB FOR MAINTENANCE THERAPY FOR ONE YEAR IN CROHN?S DISEASE: results of a Latin American single-center observational study

    Directory of Open Access Journals (Sweden)

    Paulo Gustavo KOTZE

    2014-03-01

    Full Text Available Context Adalimumab is a fully-human antibody that inhibits TNF alpha, with a significant efficacy for long-term maintenance of remission. Studies with this agent in Latin American Crohn’s disease patients are scarce. Objectives The objective of this study was to outline clinical remission rates after 12 months of adalimumab therapy for Crohn’s disease patients. Methods Retrospective, single-center, observational study of a Brazilian case series of Crohn’s disease patients under adalimumab therapy. Variables analyzed: demographic data, Montreal classification, concomitant medication, remission rates after 1, 4, 6 and 12 months. Remission was defined as Harvey-Bradshaw Index ≤4, and non-responder-imputation and last-observation-carried-forward analysis were used. The influence of infliximab on remission rates was analyzed by Fischer and Chi-square tests (P<0.05. Results Fifty patients, with median age of 35 years at therapy initiation, were included. Remission rates after 12 months of therapy were 54% under non-responder-imputation and 88% under last-observation-carried-forward analysis. After 12 months, remission on patients with previous infliximab occurred in 69.23% as compared to 94.59% in infliximab-naïve patients (P = 0.033. Conclusions Adalimumab was effective in maintaining clinical remission after 12 months of therapy, with an adequate safety profile, and was also more effective in infliximab naïve patients.

  6. Maintenance and repair of LMFBR steam generators: specialists` meeting, O-Arai Engineering Center, Japan, 4-8 June 1984. Summary report

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1984-07-01

    The Specialists` Meeting on "Maintenance and Repair of LMFBR Steam Generators" was held in Oarai, Japan, from 4-8 June 1984. The meeting was sponsored by the International Atomic Energy Agency on the recommendation of the IAEA International Working Group on Fast Reactors and was hosted by the Power Reactor and Nuclear Fuel Development Corporation of Japan. The purpose of the meeting was to review and discuss the experience accumulated in various countries on the general design philosophy of LMFBR steam generators from the view point of maintenance and repair, in-service inspection of steam generator tube bundles, identification and inspection of failed tubes and the cleaning and repairing of failed steam generators. The following main topical areas were discussed by participants: national review presentations on maintenance and repair of LMFBR steam generators - design philosophy for maintenance and repair; research and development work on maintenance and repair; and experience on steam generator maintenance and repair.

  7. Converter Compressor Building, SWMU 089, Hot Spot Areas 1, 2, and 5 Operations, Maintenance, and Monitoring Report, Kennedy Space Center, Florida

    Science.gov (United States)

    Wilson, Deborah M.

    2015-01-01

    This Operations, Maintenance, and Monitoring Report (OMMR) presents the findings, observations, and results from operation of the air sparging (AS) interim measure (IM) for Hot Spot (HS) Areas 1, 2, and 5 at the Converter Compressor Building (CCB) located at Kennedy Space Center (KSC), Florida. The objective of the IM at CCB HS Areas 1, 2, and 5 is to decrease concentrations of volatile organic compounds (VOCs) in groundwater in the treatment zones via AS to levels that will enable a transition to a monitored natural attenuation (MNA) phase. This OMMR presents system operations and maintenance (O&M) information and performance monitoring results since full-scale O&M began in June 2014 (2 months after initial system startup in April 2014), including quarterly performance monitoring events in July and October 2014 and January and May 2015. Based on the results to date, the AS system is operating as designed and is meeting the performance criteria and IM objective. The performance monitoring network is adequately constructed for assessment of IM performance at CCB HS Areas 1, 2, and 5. At the March 2014 KSC Remediation Team (KSCRT) Meeting, team consensus was reached for the design prepared for expansion of the system to treat the HS 4 area, and at the November 2014 KSCRT Meeting, team consensus was reached that HS 3 was adequately delineated horizontally and vertically and for selection of AS for the remedial approach for HS 3. At the July 2015 KSCRT meeting, team consensus was reached to continue IM operations in all zones until HSs 3 and 4 is operational, once HS 3 and 4 zones are operational discontinue operations in HS 1, 2, and 5 zones where concentrations are less than GCTLs to observe whether rebounding conditions occur. Team consensus was also reached to continue quarterly performance monitoring to determine whether operational zones achieve GCTLs and to continue annual IGWM of CCB-MW0012, CCBMW0013, and CCB-MW0056, located south of the treatment area. The

  8. Weibull distribution in reliability data analysis in nuclear power plant

    International Nuclear Information System (INIS)

    Ma Yingfei; Zhang Zhijian; Zhang Min; Zheng Gangyang

    2015-01-01

    Reliability is an important issue affecting each stage of the life cycle ranging from birth to death of a product or a system. The reliability engineering includes the equipment failure data processing, quantitative assessment of system reliability and maintenance, etc. Reliability data refers to the variety of data that describe the reliability of system or component during its operation. These data may be in the form of numbers, graphics, symbols, texts and curves. Quantitative reliability assessment is the task of the reliability data analysis. It provides the information related to preventing, detect, and correct the defects of the reliability design. Reliability data analysis under proceed with the various stages of product life cycle and reliability activities. Reliability data of Systems Structures and Components (SSCs) in Nuclear Power Plants is the key factor of probabilistic safety assessment (PSA); reliability centered maintenance and life cycle management. The Weibull distribution is widely used in reliability engineering, failure analysis, industrial engineering to represent manufacturing and delivery times. It is commonly used to model time to fail, time to repair and material strength. In this paper, an improved Weibull distribution is introduced to analyze the reliability data of the SSCs in Nuclear Power Plants. An example is given in the paper to present the result of the new method. The Weibull distribution of mechanical equipment for reliability data fitting ability is very strong in nuclear power plant. It's a widely used mathematical model for reliability analysis. The current commonly used methods are two-parameter and three-parameter Weibull distribution. Through comparison and analysis, the three-parameter Weibull distribution fits the data better. It can reflect the reliability characteristics of the equipment and it is more realistic to the actual situation. (author)

  9. With a re-engineering of maintenance to a profitably oriented maintenance

    International Nuclear Information System (INIS)

    Angelevska, Silvana; Jolevski, Tome

    2000-01-01

    This paper presents an overview of effectiveness of the profit centered maintenance as a contemporary way of the maintenance management concept. Such redesign of a maintenance procedure results in significant gains in cost reduction and increase of the profitability and competitiveness of energy. The business process re engineering - a modern management control theory that is important aspect of the profit centered maintenance is summarized

  10. Probabilistic methods for maintenance program optimization

    International Nuclear Information System (INIS)

    Liming, J.K.; Smith, M.J.; Gekler, W.C.

    1989-01-01

    In today's regulatory and economic environments, it is more important than ever that managers, engineers, and plant staff join together in developing and implementing effective management plans for safety and economic risk. This need applied to both power generating stations and other process facilities. One of the most critical parts of these management plans is the development and continuous enhancement of a maintenance program that optimizes plant or facility safety and profitability. The ultimate objective is to maximize the potential for station or facility success, usually measured in terms of projected financial profitability, while meeting or exceeding meaningful and reasonable safety goals, usually measured in terms of projected damage or consequence frequencies. This paper describes the use of the latest concepts in developing and evaluating maintenance programs to achieve maintenance program optimization (MPO). These concepts are based on significant field experience gained through the integration and application of fundamentals developed for industry and Electric Power Research Institute (EPRI)-sponsored projects on preventive maintenance (PM) program development and reliability-centered maintenance (RCM)

  11. Maintenance of scientific instruments

    International Nuclear Information System (INIS)

    Lucero, E.

    1986-01-01

    During the last years Colombia has increased the use of nuclear techniques, instruments and equipment in ambitious health programs, as well as in research centers, industry and education; this has resulted in numerous maintenance problems. As an alternative solution IAN has established a Central Maintenance Laboratory for nuclear instruments within an International Atomic Energy Agency program for eight Latin American and nine Asian Countries. Established strategies and some results are detailed in this writing

  12. 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.

  13. Space station orbit maintenance

    Science.gov (United States)

    Kaplan, D. I.; Jones, R. M.

    1983-01-01

    The orbit maintenance problem is examined for two low-earth-orbiting space station concepts - the large, manned Space Operations Center (SOC) and the smaller, unmanned Science and Applications Space Platform (SASP). Atmospheric drag forces are calculated, and circular orbit altitudes are selected to assure a 90 day decay period in the event of catastrophic propulsion system failure. Several thrusting strategies for orbit maintenance are discussed. Various chemical and electric propulsion systems for orbit maintenance are compared on the basis of propellant resupply requirements, power requirements, Shuttle launch costs, and technology readiness.

  14. Maintenance methods

    International Nuclear Information System (INIS)

    Sanchis, H.; Aucher, P.

    1990-01-01

    The maintenance method applied at the Hague is summarized. The method was developed in order to solve problems relating to: the different specialist fields, the need for homogeneity in the maintenance work, the equipment diversity, the increase of the materials used at the Hague's new facilities. The aim of the method is to create a knowhow formalism, to facilitate maintenance, to ensure the running of the operations and to improve the estimation of the maintenance cost. One of the method's difficulties is the demonstration of the profitability of the maintenance operations [fr

  15. A probabilistic maintenance model for diesel engines

    Science.gov (United States)

    Pathirana, Shan; Abeygunawardane, Saranga Kumudu

    2018-02-01

    In this paper, a probabilistic maintenance model is developed for inspection based preventive maintenance of diesel engines based on the practical model concepts discussed in the literature. Developed model is solved using real data obtained from inspection and maintenance histories of diesel engines and experts' views. Reliability indices and costs were calculated for the present maintenance policy of diesel engines. A sensitivity analysis is conducted to observe the effect of inspection based preventive maintenance on the life cycle cost of diesel engines.

  16. Maintenance Process Strategic Analysis

    Science.gov (United States)

    Jasiulewicz-Kaczmarek, M.; Stachowiak, A.

    2016-08-01

    The performance and competitiveness of manufacturing companies is dependent on the availability, reliability and productivity of their production facilities. Low productivity, downtime, and poor machine performance is often linked to inadequate plant maintenance, which in turn can lead to reduced production levels, increasing costs, lost market opportunities, and lower profits. These pressures have given firms worldwide the motivation to explore and embrace proactive maintenance strategies over the traditional reactive firefighting methods. The traditional view of maintenance has shifted into one of an overall view that encompasses Overall Equipment Efficiency, Stakeholders Management and Life Cycle assessment. From practical point of view it requires changes in approach to maintenance represented by managers and changes in actions performed within maintenance area. Managers have to understand that maintenance is not only about repairs and conservations of machines and devices, but also actions striving for more efficient resources management and care for safety and health of employees. The purpose of the work is to present strategic analysis based on SWOT analysis to identify the opportunities and strengths of maintenance process, to benefit from them as much as possible, as well as to identify weaknesses and threats, so that they could be eliminated or minimized.

  17. Integrated maintenance program (IMP)

    International Nuclear Information System (INIS)

    Zemdegs, R.T.; Chout, Q.B.

    1998-01-01

    the station's maintenance effectiveness and reduce maintenance costs including RCM4, callup overhauls, analysis of equipment and system failure history to name a few. It has become apparent that there is no single D o-All m aintenance strategy. What is needed is an integrated program combining the benefits of a variety of problem-specific strategies. Such a program should address both the short term and long term station requirements. The impact of the Integrated Maintenance Program (IMP) is expected to be high. In the short term, IMP will upgrade the call-up management system to provide accurate classification, effective monitoring and reporting, and develop a documented rationale (PMO) for each Preventive Maintenance task. To the greatest extent possible, IMP will utilize on-condition (predictive) maintenance and result in the elimination of replacement of many obsolete or ineffective preventive maintenance call-ups. The IMP described in this paper, will improve maintenance effectiveness, equipment reliability and have cost benefits to Ontario Hydro. In doing so it will reduce the cost of maintenance and improve system availability and reliability. (author)

  18. Reliability of Center of Pressure Parameters in Postural Sway among Athlete and Non-athlete Men in Different Levels of Fatigue and Vision

    Directory of Open Access Journals (Sweden)

    Zohreh Meshkati

    2010-10-01

    Full Text Available Objective: This study aimed to investigate the skill, fatigue and vision-related differences between athletes and non-athletes in reliability of center of pressure (COP measures derived from force platform. Materials & Methods: Thirty-one healthy male participants (15 athletes and 16 non-athletes were tested on force platform on two sessions with a 48-72 hr interval. COP parameters was recorded during two-legged quiet standing before and after a generalized fatigue exercise by treadmill, with eyes-open (EO and eyes-closed (EC. Standard deviation (SD of amplitude, SD of velocity in anteroposterior (AP and mediolateral directions and mean total velocity were calculated from 30 sec COP data. Results: Higher intraclass correlation coefficient (ICC was found for COP measures in the athlete (compared with the non-athlete group. ICC was increased in post-fatigue (compared with pre-fatigue conditions. Also higher ICC was found for EC (compared with EO tests. Coefficients of variation smaller than 15% were obtained for most of the COP measures. Alpha level of 0. 05 was considered for all statistical analyses. Regarding the level of skill, fatigue and vision, mean total velocity (P=0. 001 and SD of velocity (AP (P=0. 001 were the most reliable parameters. Conclusion: The results aid researchers in selection of reliable COP measures for future studies of postural control in sports. In this way, researchers can use mean total velocity and SD of velocity (AP parameters in their studies in same conditions on athletes.

  19. Operational reliability management; Gestao da confiabilidade operacional

    Energy Technology Data Exchange (ETDEWEB)

    Bressan, Edemir [Refinaria Alberto Pasqualini (REFAP), Canoas, RS (Brazil). Setor de Tecnologia de Equipamentos

    2000-07-01

    It is described the PETROBRAS Alberto Pasqualini Refinery process plant reliability management, strategies, maintenance organizational structure, management processes, predictive and preventive maintenance, condition monitoring techniques, reliability metrics, pointing out a need for close work relationship between production, maintenance and project engineering functions with highly qualified and committed proper teams, in order to reach one of the highest mechanical availability among Latin America refineries. (author)

  20. The establish and application of equipment reliability database in Nuclear Power Plant

    International Nuclear Information System (INIS)

    Zheng Wei; Li He

    2006-03-01

    Take the case of Daya Bay Nuclear Power Plant, the collecting and handling of equipment reliability data, the calculation method of reliability parameters and the establish and application of reliability databases, etc. are discussed. The data source involved the design information of the equipment, the operation information, the maintenance information and periodically test record, etc. Equipment reliability database built on a base of the operation experience. It provided the valid tool for thoroughly and objectively recording the operation history and the present condition of various equipment of the plant; supervising the appearance of the equipment, especially the safety-related equipment, provided the very practical worth information for enhancing the safety and availability management of the equipment and insuring the safety and economic operation of the plant; and provided the essential data for the research and applications in safety management, reliability analysis, probabilistic safety assessment, reliability centered maintenance and economic management in nuclear power plant. (authors)

  1. The Psychometric Properties of the Center for Epidemiologic Studies Depression Scale in Chinese Primary Care Patients: Factor Structure, Construct Validity, Reliability, Sensitivity and Responsiveness.

    Science.gov (United States)

    Chin, Weng Yee; Choi, Edmond P H; Chan, Kit T Y; Wong, Carlos K H

    2015-01-01

    The Center for Epidemiologic Studies Depression Scale (CES-D) is a commonly used instrument to measure depressive symptomatology. Despite this, the evidence for its psychometric properties remains poorly established in Chinese populations. The aim of this study was to validate the use of the CES-D in Chinese primary care patients by examining factor structure, construct validity, reliability, sensitivity and responsiveness. The psychometric properties were assessed amongst a sample of 3686 Chinese adult primary care patients in Hong Kong. Three competing factor structure models were examined using confirmatory factor analysis. The original CES-D four-structure model had adequate fit, however the data was better fit into a bi-factor model. For the internal construct validity, corrected item-total correlations were 0.4 for most items. The convergent validity was assessed by examining the correlations between the CES-D, the Patient Health Questionnaire 9 (PHQ-9) and the Short Form-12 Health Survey (version 2) Mental Component Summary (SF-12 v2 MCS). The CES-D had a strong correlation with the PHQ-9 (coefficient: 0.78) and SF-12 v2 MCS (coefficient: -0.75). Internal consistency was assessed by McDonald's omega hierarchical (ωH). The ωH value for the general depression factor was 0.855. The ωH values for "somatic", "depressed affect", "positive affect" and "interpersonal problems" were 0.434, 0.038, 0.738 and 0.730, respectively. For the two-week test-retest reliability, the intraclass correlation coefficient was 0.91. The CES-D was sensitive in detecting differences between known groups, with the AUC >0.7. Internal responsiveness of the CES-D to detect positive and negative changes was satisfactory (with p value 0.2). The CES-D was externally responsive, with the AUC>0.7. The CES-D appears to be a valid, reliable, sensitive and responsive instrument for screening and monitoring depressive symptoms in adult Chinese primary care patients. In its original four

  2. The Psychometric Properties of the Center for Epidemiologic Studies Depression Scale in Chinese Primary Care Patients: Factor Structure, Construct Validity, Reliability, Sensitivity and Responsiveness.

    Directory of Open Access Journals (Sweden)

    Weng Yee Chin

    Full Text Available The Center for Epidemiologic Studies Depression Scale (CES-D is a commonly used instrument to measure depressive symptomatology. Despite this, the evidence for its psychometric properties remains poorly established in Chinese populations. The aim of this study was to validate the use of the CES-D in Chinese primary care patients by examining factor structure, construct validity, reliability, sensitivity and responsiveness.The psychometric properties were assessed amongst a sample of 3686 Chinese adult primary care patients in Hong Kong. Three competing factor structure models were examined using confirmatory factor analysis. The original CES-D four-structure model had adequate fit, however the data was better fit into a bi-factor model. For the internal construct validity, corrected item-total correlations were 0.4 for most items. The convergent validity was assessed by examining the correlations between the CES-D, the Patient Health Questionnaire 9 (PHQ-9 and the Short Form-12 Health Survey (version 2 Mental Component Summary (SF-12 v2 MCS. The CES-D had a strong correlation with the PHQ-9 (coefficient: 0.78 and SF-12 v2 MCS (coefficient: -0.75. Internal consistency was assessed by McDonald's omega hierarchical (ωH. The ωH value for the general depression factor was 0.855. The ωH values for "somatic", "depressed affect", "positive affect" and "interpersonal problems" were 0.434, 0.038, 0.738 and 0.730, respectively. For the two-week test-retest reliability, the intraclass correlation coefficient was 0.91. The CES-D was sensitive in detecting differences between known groups, with the AUC >0.7. Internal responsiveness of the CES-D to detect positive and negative changes was satisfactory (with p value 0.2. The CES-D was externally responsive, with the AUC>0.7.The CES-D appears to be a valid, reliable, sensitive and responsive instrument for screening and monitoring depressive symptoms in adult Chinese primary care patients. In its original

  3. 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.

  4. 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

  5. Applying Systems Engineering to Improve the Main Gas Turbine Exhaust System Maintenance Strategy for the CG-47 Ticonderoga Class Cruiser

    Science.gov (United States)

    2015-09-01

    national security and prosperity (U.S. Navy 2014). In perspective, oceans are the lifeblood of the planet and its entire population . The National...maintenance strategy, reliability-centered maintenance, cost, schedule, performance, growth -work, new-work, optimal fleet response plan, time-directed...76 5. Main Gas Turbine Exhaust System Growth -Work ..................77 E. RECOMMENDATIONS TO IMPROVE THE MAIN GAS TURBINE EXHAUST SYSTEM

  6. CANDU plant maintenance: Recent developments

    International Nuclear Information System (INIS)

    Charlebois, P.

    2000-01-01

    CANDU units have long been recognized for their exceptional safety and reliability. Continuing development in the maintenance area has played a key role in achieving this performance level. For over two decades, safety system availability has been monitored closely and system maintenance programs adjusted accordingly to maintain high levels of performance. But as the plants approach mid life in a more competitive environment and component aging becomes a concern, new methods and techniques are necessary. As a result, recent developments are moving the maintenance program largely from a corrective and preventive approach to predictive and condition based maintenance. The application of these techniques is also being extended to safety related systems. These recent developments include use of reliability centred methods to define system maintenance requirements and strategies. This approach has been implemented on a number of systems at Canadian CANDU plants with positive results. The pilot projects demonstrated that the overall maintenance effort remained relatively constant while the system performance improved. It was also possible to schedule some of the redundant component maintenance during plant operation without adverse impact on system availability. The probabilistic safety assessment was found to be useful in determining the safety implications of component outages. These new maintenance strategies are now making use of predictive and condition based maintenance techniques to anticipate equipment breakdown and schedule preventive maintenance as the need arises rather than time based. Some of these techniques include valve diagnostics, vibration monitoring, oil analysis, thermography. Of course, these tools and techniques must form part of an overall maintenance management system to ensure that maintenance becomes a living program. To facilitate this process and contain costs, new information technology tools are being introduced to provide system engineers

  7. Collaborative learning in condition based maintenance

    NARCIS (Netherlands)

    Koochaki, J.; Ao, SI; Gelman, L; Hukins, DWL; Hunter, A; Korsunsky, AM

    2009-01-01

    In recent years, the importance of reliable and consistent production equipments has increased. As a result, companies are shifting their maintenance policy from preventive maintenance towards Condition Based Maintenance (CBM). Despite the growing trend in this area and success stories of CBM

  8. 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

  9. Health Services OutPatient Experience questionnaire: factorial validity and reliability of a patient-centered outcome measure for outpatient settings in Italy

    Directory of Open Access Journals (Sweden)

    Coluccia A

    2014-09-01

    Full Text Available Anna Coluccia, Fabio Ferretti, Andrea PozzaDepartment of Medical Sciences, Surgery and Neurosciences, Santa Maria alle Scotte University Hospital, University of Siena, Siena, ItalyPurpose: The patient-centered approach to health care does not seem to be sufficiently developed in the Italian context, and is still characterized by the biomedical model. In addition, there is a lack of validated outcome measures to assess outpatient experience as an aspect common to a variety of settings. The current study aimed to evaluate the factorial validity, reliability, and invariance across sex of the Health Services OutPatient Experience (HSOPE questionnaire, a short ten-item measure of patient-centeredness for Italian adult outpatients. The rationale for unidimensionality of the measure was that it could cover global patient experience as a process common to patients with a variety of diseases and irrespective of the phase of treatment course.Patients and methods: The HSOPE was compiled by 1,532 adult outpatients (51% females, mean age 59.22 years, standard deviation 16.26 receiving care in ten facilities at the Santa Maria alle Scotte University Hospital of Siena, Italy. The sample represented all the age cohorts. Twelve percent were young adults, 57% were adults, and 32% were older adults. Exploratory and confirmatory factor analyses were conducted to evaluate factor structure. Reliability was evaluated as internal consistency using Cronbach’s α. Factor invariance was assessed through multigroup analyses.Results: Both exploratory and confirmatory analyses suggested a clearly defined unidimensional structure of the measure, with all the ten items having salient loadings on a single factor. Internal consistency was excellent (α=0.95. Indices of model fit supported a single-factor structure for both male and female outpatient groups. Young adult outpatients had significantly lower scores on perceived patient-centeredness relative to older adults. No

  10. Development of plant maintenance systems

    International Nuclear Information System (INIS)

    Tomita, Jinji; Ike, Masae; Nakayama, Kenji; Kato, Hisatomo

    1989-01-01

    Toshiba is making active efforts for the continuing improvement of reliability and maintainability of operating nuclear power plants. As a part of these efforts, the company has developed new maintenance administration systems, diagnostic monitoring facilities for plant equipments, computer-aided expert systems, and remote-controlled machines for maintenance work. The maintenance administration systems provide efficient work plans and data acquisition capabilities for the management of personnel and equipments involved in nuclear power plant maintenance. The plant diagnostic facilities monitor and diagnose plant conditions for preventive maintenance, as well as enabling rapid countermeasures to be carried out should they be required. Expert systems utilizing artificial intelligence (AI) technology are also employed. The newly developed remote-controlled machines are useful tools for the maintenance inspection of equipment which can not be easily accessed. (author)

  11. The maintenance optimization of structural components in nuclear power plants

    International Nuclear Information System (INIS)

    Bryla, P.; Ardorino, F.; Aufort, P.; Jacquot, J.P.; Magne, L.; Pitner, P.; Verite, B.; Villain, B.; Monnier, B.

    1997-10-01

    An optimization process, called 'OMF-Structures', is developed by Electricite de France (EDF) in order to extend the current 'OMF' Reliability Centered Maintenance to piping structural components. The Auxiliary Feedwater System of a 900 MW French nuclear plant has been studied in order to lay the foundations of the method. This paper presents the currently proposed principles of the process. The principles of the OMF-Structures process include 'Risk-Based Inspection' concepts within an RCM process. Two main phases are identified: The purpose of the first phase is to select the risk-significant failure modes and associated elements. This phase consists of two major steps: potential consequences evaluation and reliability performance evaluation. The second phase consists of the definition of preventive maintenance programs for piping elements that are associated with risk-significant failure modes. (author)

  12. A point of application study to determine the accuracy, precision and reliability of a low-cost balance plate for center of pressure measurement.

    Science.gov (United States)

    Goble, Daniel J; Khan, Ehran; Baweja, Harsimran S; O'Connor, Shawn M

    2018-04-11

    Changes in postural sway measured via force plate center of pressure have been associated with many aspects of human motor ability. A previous study validated the accuracy and precision of a relatively new, low-cost and portable force plate called the Balance Tracking System (BTrackS). This work compared a laboratory-grade force plate versus BTrackS during human-like dynamic sway conditions generated by an inverted pendulum device. The present study sought to extend previous validation attempts for BTrackS using a more traditional point of application (POA) approach. Computer numerical control (CNC) guided application of ∼155 N of force was applied five times to each of 21 points on five different BTrackS Balance Plate (BBP) devices with a hex-nose plunger. Results showed excellent agreement (ICC > 0.999) between the POAs and measured COP by the BBP devices, as well as high accuracy ( 0.999) providing evidence of almost perfect inter-device reliability. Taken together, these results provide an important, static corollary to the previously obtained dynamic COP results from inverted pendulum testing of the BBP. Copyright © 2018 Elsevier Ltd. All rights reserved.

  13. Maintenance Mentor

    National Research Council Canada - National Science Library

    Jacobs, John

    2003-01-01

    Maintenance Mentor (MXM) is a research effort conducted by a joint AFRL/HESR and Northrop Grumman Information Technology team to identify the basic, high-level requirements necessary for improving flight line diagnostic capabilities...

  14. Education and training of operators and maintenance staff at Hamaoka Nuclear Power Stations

    International Nuclear Information System (INIS)

    Makido, Hideki; Hayashi, Haruhisa

    1999-01-01

    At Hamaoka Nuclear Power Station, in order to ensure higher safety and reliability of plant operation, education and training is provided consistently, on a comprehensive basis, for all operating, maintenance and other technical staff, aimed at developing more capable human resources in the nuclear power division. To this end, Hamaoka Nuclear Power Station has the 'Nuclear Training Center' on its site. The training center provides the technical personnel including operators and maintenance personnel with practical training, utilizing simulators for operation training and the identical facilities with those at the real plant. Thus, it plays a central role in promoting comprehensive education and training concerning nuclear power generation. Our education system covers knowledge and skills necessary for the safe and stable operation of nuclear power plant, targeting new employees to managerial personnel. It is also organized systematically in accordance with experience and job level. We will report the present education and training of operators and maintenance personnel at Hamaoka Nuclear Training Center. (author)

  15. Fleet Aviation Maintenance Organic Support (FAMOS) Laboratory

    Data.gov (United States)

    Federal Laboratory Consortium — Purpose:The Fleet Aviation Maintenance Organic Support (FAMOS) Laboratory at the Naval Air Warfare Center Aircraft Division, Lakehurst, NJ provides rapid engineering...

  16. Instrumentation maintenance

    International Nuclear Information System (INIS)

    Mack, D.A.

    1976-09-01

    It is essential to any research activity that accurate and efficient measurements be made for the experimental parameters under consideration for each individual experiment or test. Satisfactory measurements in turn depend upon having the necessary instruments and the capability of ensuring that they are performing within their intended specifications. This latter requirement can only be achieved by providing an adequate maintenance facility, staffed with personnel competent to understand the problems associated with instrument adjustment and repair. The Instrument Repair Shop at the Lawrence Berkeley Laboratory is designed to achieve this end. The organization, staffing and operation of this system is discussed. Maintenance policy should be based on studies of (1) preventive vs. catastrophic maintenance, (2) records indicating when equipment should be replaced rather than repaired and (3) priorities established to indicate the order in which equipment should be repaired. Upon establishing a workable maintenance policy, the staff should be instructed so that they may provide appropriate scheduled preventive maintenance, calibration and corrective procedures, and emergency repairs. The education, training and experience of the maintenance staff is discussed along with the organization for an efficient operation. The layout of the various repair shops is described in the light of laboratory space and financial constraints

  17. Predictive maintenance primer

    International Nuclear Information System (INIS)

    Flude, J.W.; Nicholas, J.R.

    1991-04-01

    This Predictive Maintenance Primer provides utility plant personnel with a single-source reference to predictive maintenance analysis methods and technologies used successfully by utilities and other industries. It is intended to be a ready reference to personnel considering starting, expanding or improving a predictive maintenance program. This Primer includes a discussion of various analysis methods and how they overlap and interrelate. Additionally, eighteen predictive maintenance technologies are discussed in sufficient detail for the user to evaluate the potential of each technology for specific applications. This document is designed to allow inclusion of additional technologies in the future. To gather the information necessary to create this initial Primer the Nuclear Maintenance Applications Center (NMAC) collected experience data from eighteen utilities plus other industry and government sources. NMAC also contacted equipment manufacturers for information pertaining to equipment utilization, maintenance, and technical specifications. The Primer includes a discussion of six methods used by analysts to study predictive maintenance data. These are: trend analysis; pattern recognition; correlation; test against limits or ranges; relative comparison data; and statistical process analysis. Following the analysis methods discussions are detailed descriptions for eighteen technologies analysts have found useful for predictive maintenance programs at power plants and other industrial facilities. Each technology subchapter has a description of the operating principles involved in the technology, a listing of plant equipment where the technology can be applied, and a general description of the monitoring equipment. Additionally, these descriptions include a discussion of results obtained from actual equipment users and preferred analysis techniques to be used on data obtained from the technology. 5 refs., 30 figs

  18. 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

  19. 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.)

  20. DATMAN: A reliability data analysis program using Bayesian updating

    International Nuclear Information System (INIS)

    Becker, M.; Feltus, M.A.

    1996-01-01

    Preventive maintenance (PM) techniques focus on the prevention of failures, in particular, system components that are important to plant functions. Reliability-centered maintenance (RCM) improves on the PM techniques by introducing a set of guidelines by which to evaluate the system functions. It also minimizes intrusive maintenance, labor, and equipment downtime without sacrificing system performance when its function is essential for plant safety. Both the PM and RCM approaches require that system reliability data be updated as more component failures and operation time are acquired. Systems reliability and the likelihood of component failures can be calculated by Bayesian statistical methods, which can update these data. The DATMAN computer code has been developed at Penn State to simplify the Bayesian analysis by performing tedious calculations needed for RCM reliability analysis. DATMAN reads data for updating, fits a distribution that best fits the data, and calculates component reliability. DATMAN provides a user-friendly interface menu that allows the user to choose from several common prior and posterior distributions, insert new failure data, and visually select the distribution that matches the data most accurately

  1. Development of advanced human-machine system for plant operation and maintenance

    International Nuclear Information System (INIS)

    Wu, Wei; Ohi, Tadashi; Yoshikawa, Hidekazu; Sawaragi, Tetsuo; Kitamura, Masaharu; Furuta, Kazuo; Gofuku, Akio; Ito, Koji

    2004-01-01

    With the worldwide deregulation of the power industry, and the aging of the nuclear power plants (NPPs), concerns are growing over the reliability and safety of the NPPs, because the regulation of man power may lower the current high level of reliability and safety. In this paper, a concept of overall integrated plant management mechanism is proposed, in order to meet the requirements of cutting costs of NPPs and the requirements of maintaining or increasing safety and reliability. The concept is called as satellite operation maintenance center (SOMC). SOMC integrates the operation and maintenance activities of several NPP units by utilizing advanced information technologies to support cooperation activities between workers allocated at SOMC and the field workers. As for the operation activities, a framework called as Advanced Operation System (AOS) is proposed in this paper. AOS consists of three support sub-systems: dynamic operation permission system(DyOPS), supervisor information presentation system using interface agent, and crew performance evaluation system. As for the maintenance activities, a framework called as Ubiquitous-Computing-based Maintenance support System (UCMS) is proposed next. Two case studies are described, in order to show the way of how UCMS support field workers to do maintenance tasks efficiently, safely, and infallibly as well. Finally, a prospect of SOMC is shown in order to explain the way of how the technology elements developed in this project could be integrated as a whole one system to support maintenance activities of NPPs in the future. (author)

  2. Intravenous immunoglobulin for maintenance treatment of multifocal motor neuropathy: A multi-center, open-label, 52-week phase 3 trial.

    Science.gov (United States)

    Kuwabara, Satoshi; Misawa, Sonoko; Mori, Masahiro; Iwai, Yuta; Ochi, Kazuhide; Suzuki, Hidekazu; Nodera, Hiroyuki; Tamaoka, Akira; Iijima, Masahiro; Toda, Tatsushi; Yoshikawa, Hiroo; Kanda, Takashi; Sakamoto, Ko; Kusunoki, Susumu; Sobue, Gen; Kaji, Ryuji

    2018-04-10

    Intravenous immunoglobulin (IVIg) therapy is currently the only established treatment in patients with multifocal motor neuropathy (MMN), and many patients have an IVIg-dependent fluctuation. We aimed to investigate the efficacy and safety of every 3 week IVIg (1.0 g/kg) for 52 weeks. This study was an open-label phase 3 clinical trial, enrolling 13 MMN patients. After an induction IVIg therapy (0.4 g/kg/d for 5 consecutive days), maintenance dose (1.0 g/kg) was given every 3 weeks for 52 weeks. The major outcome measures were the Medical Research Council (MRC) sum score and hand-grip strength at week 52. This trial is registered with ClinicalTrials.gov, number NCT01827072. At week 52, 11 of the 13 patients completed the study, and all 11 had a sustained improvement. The mean (SD) MRC sum score was 85.6 (8.7) at the baseline, and 90.6 (12.8) at week 52. The mean grip strength was 39.2 (30.0) kPa at the baseline and 45.2 (32.8) kPa at week 52. Two patients dropped out because of adverse event (dysphagia) and decision of an investigator, respectively. Three patients developed coronary spasm, dysphagia, or inguinal herniation, reported as the serious adverse events, but considered not related with the study drug. The other adverse effects were mild and resolved by the end of the study period. Our results show that maintenance treatment with 1.0 g/kg IVIg every 3 week is safe and efficacious for MMN patients up to 52 weeks. Further studies are required to investigate optimal dose and duration of maintenance IVIg for MMN. © 2018 The Authors. Journal of the Peripheral Nervous System published by Wiley Periodicals, Inc. on behalf of Peripheral Nerve Society.

  3. City gates maintenance - TBG experience; Experiencia da TBG na manutencao de estacoes de entrega de gas natural

    Energy Technology Data Exchange (ETDEWEB)

    Rocha, Adir de Brito; Tavares, Cipriano Homem; Pinto, Jose Eduardo Christovao [Transportadora Brasileira Gasoduto Bolivia-Brasil, S.A., Rio de Janeiro, RJ (Brazil)

    2005-07-01

    Owner and sole operator in Brasilian territory of the Bolivia-Brazil Gas Pipeline (GASBOL), the largest of its kind in South America, TBG started operations on July 1 st, 1999. Since then, it has ensured transportation of Bolivian natural gas into Brazil swiftly and safely. This paper relates the TBG experiences on Natural Gas City Gates maintenance and its components like filtering, heating, pressure reducing redundant valves, turbine meters, flow computers, solar panel power supply, satellite monitoring system, acquired by 6 years of operation of Brazil Bolivia Gas Pipe Line. It describes the definitions of maintenance plans using RCM - Reliability-centered Maintenance concepts and the most important learning experiences. (author)

  4. Proceedings of the third international conference on CANDU maintenance

    International Nuclear Information System (INIS)

    1995-01-01

    The third international conference on Candu maintenance included sessions on the following topics: predictive maintenance, reliability improvements, steam generator monitoring, tools and instrumentation, valve performance, fuel channel inspection and maintenance, steam generator maintenance, environmental qualification, predictive maintenance, instrumentation and control, steam generator cleaning, decontamination and radiation protection, inspection techniques, maintenance program strategies and valve packing experience, remote tooling/ robotics and fuel handling. The individual papers have been abstracted separately

  5. Proceedings of the third international conference on CANDU maintenance

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-12-31

    The third international conference on Candu maintenance included sessions on the following topics: predictive maintenance, reliability improvements, steam generator monitoring, tools and instrumentation, valve performance, fuel channel inspection and maintenance, steam generator maintenance, environmental qualification, predictive maintenance, instrumentation and control, steam generator cleaning, decontamination and radiation protection, inspection techniques, maintenance program strategies and valve packing experience, remote tooling/ robotics and fuel handling. The individual papers have been abstracted separately.

  6. Achievement report for fiscal 1998. Research and development of a multi-plant maintenance system (the first year); 1998 nendo seika hokokusho. Odanteki maintenance gijutsu no kenkyu kaihatsu (dai 1 nendo)

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1999-03-01

    This research and development is intended to structure a network centering around a center having systematized high-level maintenance technology, by utilizing the technological infrastructure having been built in local areas, together with element technologies possessed by national and private research institutes, universities and colleges. It is also purposed to establish a new industrial system for maintenance to realize high reliability, high operation rate and low cost in plants in certain areas. The present fiscal year had the following achievements: research and development of a maintenance system, a maintenance model, a maintenance vehicle, damage estimating technology for stationary parts such as piping, an anomaly diagnostic system using acoustic emission, an anomaly diagnostic system using wear particles in lubricant, an anti-wear material using surface modification, a lubrication control system, and an anomaly diagnostic system using ultrasonic waves. The research and development executing organization was divided into four groups for the maintenance system, maintenance model, maintenance vehicle, and maintenance tool. All groups have achieved the initial plans satisfactorily. (NEDO)

  7. 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.

  8. Vicinal 1H-1H NMR coupling constants from density functional theory as reliable tools for stereochemical analysis of highly flexible multichiral center molecules.

    Science.gov (United States)

    López-Vallejo, Fabian; Fragoso-Serrano, Mabel; Suárez-Ortiz, Gloria Alejandra; Hernández-Rojas, Adriana C; Cerda-García-Rojas, Carlos M; Pereda-Miranda, Rogelio

    2011-08-05

    A protocol for stereochemical analysis, based on the systematic comparison between theoretical and experimental vicinal (1)H-(1)H NMR coupling constants, was developed and applied to a series of flexible compounds (1-8) derived from the 6-heptenyl-5,6-dihydro-2H-pyran-2-one framework. The method included a broad conformational search, followed by geometry optimization at the DFT B3LYP/DGDZVP level, calculation of the vibrational frequencies, thermochemical parameters, magnetic shielding tensors, and the total NMR spin-spin coupling constants. Three scaling factors, depending on the carbon atom hybridizations, were found for the (1)H-C-C-(1)H vicinal coupling constants: f((sp3)-(sp3)) = 0.910, f((sp3)-(sp2)) = 0.929, and f((sp2)-(sp2))= 0.977. A remarkable correlation between the theoretical (J(pre)) and experimental (1)H-(1)H NMR (J(exp)) coupling constants for spicigerolide (1), a cytotoxic natural product, and some of its synthetic stereoisomers (2-4) demonstrated the predictive value of this approach for the stereochemical assignment of highly flexible compounds containing multiple chiral centers. The stereochemistry of two natural 6-heptenyl-5,6-dihydro-2H-pyran-2-ones (14 and 15) containing diverse functional groups in the heptenyl side chain was also analyzed by application of this combined theoretical and experimental approach, confirming its reliability. Additionally, a geometrical analysis for the conformations of 1-8 revealed that weak hydrogen bonds substantially guide the conformational behavior of the tetraacyloxy-6-heptenyl-2H-pyran-2-ones.

  9. Application of Bayesian statistical decision theory for a maintenance optimization problem

    International Nuclear Information System (INIS)

    Procaccia, H.; Cordier, R.; Muller, S.

    1997-01-01

    Reliability-centered maintenance (RCM) is a rational approach that can be used to identify the equipment of facilities that may turn out to be critical with respect to safety, to availability, or to maintenance costs. Is is dor these critical pieces of equipment alone that a corrective (one waits for a failure) or preventive (the type and frequency are specified) maintenance policy is established. But this approach has limitations: - when there is little operating feedback and it concerns rare events affecting a piece of equipment judged critical on a priori grounds (how is it possible, in this case, to decide whether or not it is critical, since there is conflict between the gravity of the potential failure and its frequency?); - when the aim is propose an optimal maintenance frequency for a critical piece of equipment - changing the maintenance frequency hitherto applied may cause a significant drift in the observed reliability of the equipment, an aspect not generally taken into account in the RCM approach. In these two situations, expert judgments can be combined with the available operating feedback (Bayesian approach) and the combination of risk of failure and economic consequences taken into account (statistical decision theory) to achieve a true optimization of maintenance policy choices. This paper presents an application on the maintenance of diesel generator component

  10. Component-Based Data-Driven Predictive Maintenance to Reduce Unscheduled Maintenance Events

    NARCIS (Netherlands)

    Verhagen, W.J.C.; Curran, R.; de Boer, L.W.M.; Chen, C.H.; Trappey, A.C.; Peruzzini, M.; Stjepandić, J.; Wognum, N.

    2017-01-01

    Costs associated with unscheduled and preventive maintenance can contribute significantly to an airline's expenditure. Reliability analysis can help to identify and plan for maintenance events. Reliability analysis in industry is often limited to statistically based

  11. Maintenance of radiation monitoring systems

    International Nuclear Information System (INIS)

    Aoyama, Kei

    2001-01-01

    As the safety and quality of atomic power facilities are more strongly required, the reliability improvement and preventive maintenance of radiation monitoring systems are important. This paper describes the maintenance of radiation monitoring systems delivered by Fuji Electric and the present status of preventive maintenance technology. Also it introduces the case that we developed a fault diagnosis function adopting a statistics technique and artificial intelligence (AI) and delivered a radiation monitoring system including this function. This system can output a fault analysis result and a countermeasure from the computer in real time. (author)

  12. Maintenance, a global approach

    International Nuclear Information System (INIS)

    Calmejane, P.

    2001-01-01

    Maintenance is an important economic activity, it can represent up to 40% of operating costs in some fabrication units. The opening of energy markets to competition has led main operators to center their activities on their basis business and to sub-contract subsidiary activities. Subcontracting with strong engagements from the sub-contractor about results, time allowed and costs is now currently applied in nuclear industry. (A.C.)

  13. design of preventive maintenance scheduling model for ...

    African Journals Online (AJOL)

    connected in parallel, Rj(ti) is the reliability of the jth unit at ith time interval, n is the to- tal number of systems (components or units) connected in parallel. Equations (3) and (4) enable us to deter- mine the reliability of all components, units or sub-systems in an industry. 5. System Reliability with Preventive. Maintenance. Fig.

  14. The Korean version of relative and absolute reliability of gait and balance assessment tools for patients with dementia in day care center and nursing home.

    Science.gov (United States)

    Lee, Han Suk; Park, Sun Wook; Chung, Hyung Kuk

    2017-11-01

    [Purpose] This study was aimed to determine the relative and absolute reliability of Korean version tools of the Berg Balance Scale (BBS), the Timed Up and Go (TUG), the Four-Meter Walking Test (4MWT) and the Groningen Meander Walking Test (GMWT) in patients with dementia. [Subjects and Methods] A total of 53 patients with dementia were tested on TUG, BBS, 4MWT and GMWT with a prospective cohort methodological design. Intra-class Correlation Coefficients (ICCs) to assess relative reliability and the standard error of measurement (SEM), minimal detectable change (MDC 95 ) and its percentage (MDC % ) to analyze the absolute reliability were calculated. [Results] Inter-rater reliability (ICC (2,3) ) of TUG, BBS and GMWT was 0.99 and that of 4MWT was 0.82. Inter-rater reliability was high for TUG, BBS and GMWT, with low SEM, MDC 95 , and MDC % . Inter-rater reliability was low for 4MWT, with high SEM, MDC 95 , and MDC % . Test-retest (ICC (2,3) ) of TUG, BBS and GMWT was 0.96-0.99 and Test-retest (ICC (2,3) ) of 4MWT was 0.85. The test-retest was high for TUG, BBS and GMWT, with low SEM, MDC 95 , and MDC % , but it was low for 4MWT, with high SEM, MDC 95 , and MDC % . [Conclusion] The relative reliability was high for all the assessment tools. The absolute reliability has a reasonable level of stability except the 4MWT.

  15. Application of genetic algorithms to the maintenance scheduling optimization in a nuclear system basing on reliability; Aplicacao de algoritmos geneticos na otimizacao da politica de manutencoes preventivas de um sistema nuclear centrada em confiabilidade

    Energy Technology Data Exchange (ETDEWEB)

    Lapa, Celso M. Franklin; Pereira, Claudio M.N.A.; Mol, Antonio C. de Abreu [Instituto de Engenharia Nuclear (IEN), Rio de Janeiro, RJ (Brazil)

    1999-07-01

    This paper presents a solution based on genetic algorithm and probabilistic safety analysis that can be applied in the optimization of the preventive maintenance politic of nuclear power plant safety systems. The goal of this approach is to improve the average availability of the system through the optimization of the preventive maintenance scheduling politic. The auxiliary feed water system of a two loops pressurized water reactor is used as a sample case, in order to demonstrate the effectiveness of the proposed method. The results, when compared to those obtained by some standard maintenance politics, reveal quantitative gains and operational safety levels. (author)

  16. Lean Maintenance Applied to Improve Maintenance Efficiency in Thermoelectric Power Plants

    OpenAIRE

    Orlando Duran; Andrea Capaldo; Paulo Andrés Duran Acevedo

    2017-01-01

    Thermoelectric power plants consist of a set of critical equipment that require high levels of availability and reliability. Due to this, maintenance of these physical assets is gaining momentum in industry. Maintenance is considered as an activity that contributes to improving the availability, efficiency and productivity of each piece of equipment. Several techniques have been used to achieve greater efficiencies in maintenance, among which we can find the lean maintenance philosophy. Despi...

  17. Reliability Modeling of Wind Turbines

    DEFF Research Database (Denmark)

    Kostandyan, Erik

    Cost reductions for offshore wind turbines are a substantial requirement in order to make offshore wind energy more competitive compared to other energy supply methods. During the 20 – 25 years of wind turbines useful life, Operation & Maintenance costs are typically estimated to be a quarter...... for Operation & Maintenance planning. Concentrating efforts on development of such models, this research is focused on reliability modeling of Wind Turbine critical subsystems (especially the power converter system). For reliability assessment of these components, structural reliability methods are applied...... to one third of the total cost of energy. Reduction of Operation & Maintenance costs will result in significant cost savings and result in cheaper electricity production. Operation & Maintenance processes mainly involve actions related to replacements or repair. Identifying the right times when...

  18. Selection of maintenance tasks

    Energy Technology Data Exchange (ETDEWEB)

    Dean, B; Rombos, P [Wardrop (W.L.) and Associates Ltd., Winnipeg, MB (Canada)

    1995-10-01

    Two methodologies for maintenance task selection, Reliability Centre Maintenance (RCM) and Degradation Mode Analysis (DMA), are compared with regard to application in the nuclear industry and potential for application at CANDU nuclear power plants. RCM is the favoured one of the two methodologies. It is more thorough than DMA, is well supported within the US nuclear industry, and - with experience in application - is gaining cost effectiveness. There is interest in the use of RCM in other nations, including France and Japan, and it is already being implemented at Bruce A NGS and Bruce B NGS in Canada. DMA lags behind RCM in development and currently there is little experience to support claims of major benefits at reduced cost. Significant advantages over RCM need to be demonstrated if DMA is to gain acceptance in the nuclear industry. (author). 41 refs., 7 tabs., 8 figs.

  19. Selection of maintenance tasks

    International Nuclear Information System (INIS)

    Dean, B.; Rombos, P.

    1995-10-01

    Two methodologies for maintenance task selection, Reliability Centre Maintenance (RCM) and Degradation Mode Analysis (DMA), are compared with regard to application in the nuclear industry and potential for application at CANDU nuclear power plants. RCM is the favoured one of the two methodologies. It is more thorough than DMA, is well supported within the US nuclear industry, and - with experience in application - is gaining cost effectiveness. There is interest in the use of RCM in other nations, including France and Japan, and it is already being implemented at Bruce A NGS and Bruce B NGS in Canada. DMA lags behind RCM in development and currently there is little experience to support claims of major benefits at reduced cost. Significant advantages over RCM need to be demonstrated if DMA is to gain acceptance in the nuclear industry. (author). 41 refs., 7 tabs., 8 figs

  20. Excellence method in maintenance with application for cryogenic nuclear unit (EMAC)

    International Nuclear Information System (INIS)

    Anghel, Vasile

    2006-01-01

    Full text: Cryogenic Nuclear Plant (CNP) has as main objectives the development of a technology for the removal of tritium from heavy water used in nuclear plants of CANDU type and finding of a methodology for complete inspection of the equipment used in the presence of tritium at very low temperatures. These aims imply achieving two main stages. The first stage concerns the maintenance conception on a scientific basis, while the second stage concerns the implementation. The first stage implies the management of maintenance in constraints relating to quality, risk and cost. The second stage regards the aspect of design and technology of CNP maintenance. The solution adequate with this conception will lead to a solution viable for implementation. The operative maintenance will be based on RCM (Reliability Centered Maintenance), using NOLAN and HEAP 1978 methodologies. The integrated maintenance through research and implementation demonstrates the design, realization of equipment, the dynamic and and the static complex uses of EMAC in CNP. It is a method of conception and implementation that integrates maintenance for the life cycle in the considered cryogenics systems. The implementation is achieved by means of the software LabVIEW applied to the specific objectives of the Program for Operative Maintenance in Temporal Dynamic Regime (POMTDR). (author)

  1. Optimal maintenance of a multi-unit system under dependencies

    Science.gov (United States)

    Sung, Ho-Joon

    same end-goals as Reliability Centered Maintenance (RCM). RCM was first introduced to the aircraft industry in an attempt to bridge the gap between the empirically-driven and theory-driven approaches to establishing optimal maintenance policies. Under RCM, qualitative processes that enable the prioritizing of functions based on the criticality and influence would be combined with mathematical modeling to obtain the optimal maintenance policies. Where this thesis work deviates from RCM is its proposal to directly apply quantitative processes to model the reliability measures in optimal maintenance problem. First, Monte Carlo (MC) simulation, in conjunction with a pre-determined Design of Experiments (DOE) table, can be used as a numerical means of obtaining the corresponding discrete simulated outcomes of the reliability measures based on the combination of decision variables (e.g., periodic preventive maintenance interval, trigger age for opportunistic maintenance, etc.). These discrete simulation results can then be regressed as Response Surface Equations (RSEs) with respect to the decision variables. Such an approach to represent the reliability measures with continuous surrogate functions (i.e., the RSEs) not only enables the application of the numerical optimization technique to solve for optimal maintenance policies, but also obviates the need to make mathematical assumptions or impose over-simplifications on the structure of a multi-unit system for the sake of mathematical tractability. The applicability of the proposed methodology to a real-world optimal maintenance problem is showcased through its application to a Time Limited Dispatch (TLD) of Full Authority Digital Engine Control (FADEC) system. In broader terms, this proof-of-concept exercise can be described as a constrained optimization problem, whose objective is to identify the optimal system inspection interval that guarantees a certain level of availability for a multi-unit system. A variety of

  2. Maintenance philosophy and program at Cernavoda NPP

    International Nuclear Information System (INIS)

    Bobos, M.; Enciu, G.

    1994-01-01

    Maintenance plays a key role in ensuring safe and reliable operation. An effective maintenance program should ensure that installed equipment operates when needed and the equipment malfunctions or deficiencies are corrected in time and rarely recur. Maintenance includes not only the activities traditionally associated with identifying or correcting current or potential equipment deficiencies but also extends to supporting technical functions for the conduct of these activities (for example, engineering, technical support, chemistry control, radiological protection, industrial safety and training). The maintenance management program should clearly define the relationship among these supporting groups as it is related to overall plant maintenance and promotes the concept of a successful integrated team effort. (Author)

  3. Equipment Maintenance management support system based on statistical analysis of maintenance history data

    International Nuclear Information System (INIS)

    Shimizu, S.; Ando, Y.; Morioka, T.

    1990-01-01

    Plant maintenance is recently becoming important with the increase in the number of nuclear power stations and in plant operating time. Various kinds of requirements for plant maintenance, such as countermeasures for equipment degradation and saving maintenance costs while keeping up plant reliability and productivity, are proposed. For this purpose, plant maintenance programs should be improved based on equipment reliability estimated by field data. In order to meet these requirements, it is planned to develop an equipment maintenance management support system for nuclear power plants based on statistical analysis of equipment maintenance history data. The large difference between this proposed new method and current similar methods is to evaluate not only failure data but maintenance data, which includes normal termination data and some degree of degradation or functional disorder data for equipment and parts. So, it is possible to utilize these field data for improving maintenance schedules and to evaluate actual equipment and parts reliability under the current maintenance schedule. In the present paper, the authors show the objectives of this system, an outline of this system and its functions, and the basic technique for collecting and managing of maintenance history data on statistical analysis. It is shown, from the results of feasibility tests using simulation data of maintenance history, that this system has the ability to provide useful information for maintenance and the design enhancement

  4. Opportunities and supporting activities to promote preventive maintenance of NPPs in Japan

    International Nuclear Information System (INIS)

    Sanada, A.; Shinkawa, T.; Sakurada, M.

    1998-01-01

    With increase of the number of NPPs and operation history, enhancement of the safety regulation is becoming important for such long-operated NPPs. Centering on the comprehensive preventive maintenance, periodic safety reviews by utilities and its review and evaluation by MITI are in progress. The first reviews have not revealed essential and critical indications to be newly implemented. This means that the most of activities to secure reliability and safety have been done steadily. The present paper addresses the mechanism of on-going preventive maintenance and its essential elements: opportunities to identify issues and problems, and supporting activities to promote decision-makings on feedback, upgrading and modernization of NPPs. (author)

  5. Space Flight Operations Center local area network

    Science.gov (United States)

    Goodman, Ross V.

    1988-01-01

    The existing Mission Control and Computer Center at JPL will be replaced by the Space Flight Operations Center (SFOC). One part of the SFOC is the LAN-based distribution system. The purpose of the LAN is to distribute the processed data among the various elements of the SFOC. The SFOC LAN will provide a robust subsystem that will support the Magellan launch configuration and future project adaptation. Its capabilities include (1) a proven cable medium as the backbone for the entire network; (2) hardware components that are reliable, varied, and follow OSI standards; (3) accurate and detailed documentation for fault isolation and future expansion; and (4) proven monitoring and maintenance tools.

  6. Maintenance in sustainable manufacturing

    Directory of Open Access Journals (Sweden)

    Vladimir Stuchly

    2014-09-01

    Full Text Available Background: Sustainable development is about reaching a balance between economic, social, and environmental goals, as well as people's participation in the planning process in order to gain their input and support. For a company, sustainable development means adoption of such business strategy and actions that contribute to satisfying present needs of company and stakeholders, as well as simultaneous protection, maintenance and strengthening of human and environmental potential which will be needed in the future. This new approach forces manufacturing companies to change their previous management paradigms. New management paradigm should include new issues and develop innovative methods, practices and technologies striving for solving problem of shortages of resources, softening environment overload and enabling development of environment-friendly lifecycle of products. Hence, its realization requires updating existing production models as they are based on previously accepted paradigm of unlimited resources and unlimited regeneration capabilities. Maintenance plays a crucial role because of its impact on availability, reliability, quality and life cycle cost, thus it should be one of the main pillars of new business running model.  Material and methods: The following paper is a result of research on the literature and observation of practices undertaken by a company within maintenance area. Results and conclusions: The main message is that considering sustainable manufacturing requires considerable expanding range of analysis and focusing on supporting processes. Maintenance offers numerous opportunities of decreasing influence of business processes on natural environment and more efficient resources utilization. The goal of maintenance processes realizing sustainable development strategy is increased profitability of exploitation and optimization of total lifecycle cost without disturbing safety and environmental issues. 

  7. GRAPHICAL MODELS OF THE AIRCRAFT MAINTENANCE PROCESS

    Directory of Open Access Journals (Sweden)

    Stanislav Vladimirovich Daletskiy

    2017-01-01

    Full Text Available The aircraft maintenance is realized by a rapid sequence of maintenance organizational and technical states, its re- search and analysis are carried out by statistical methods. The maintenance process concludes aircraft technical states con- nected with the objective patterns of technical qualities changes of the aircraft as a maintenance object and organizational states which determine the subjective organization and planning process of aircraft using. The objective maintenance pro- cess is realized in Maintenance and Repair System which does not include maintenance organization and planning and is a set of related elements: aircraft, Maintenance and Repair measures, executors and documentation that sets rules of their interaction for maintaining of the aircraft reliability and readiness for flight. The aircraft organizational and technical states are considered, their characteristics and heuristic estimates of connection in knots and arcs of graphs and of aircraft organi- zational states during regular maintenance and at technical state failure are given. It is shown that in real conditions of air- craft maintenance, planned aircraft technical state control and maintenance control through it, is only defined by Mainte- nance and Repair conditions at a given Maintenance and Repair type and form structures, and correspondingly by setting principles of Maintenance and Repair work types to the execution, due to maintenance, by aircraft and all its units mainte- nance and reconstruction strategies. The realization of planned Maintenance and Repair process determines the one of the constant maintenance component. The proposed graphical models allow to reveal quantitative correlations between graph knots to improve maintenance processes by statistical research methods, what reduces manning, timetable and expenses for providing safe civil aviation aircraft maintenance.

  8. Opportune maintenance and predictive maintenance decision support

    OpenAIRE

    Thomas , Edouard; Levrat , Eric; Iung , Benoît; Cocheteux , Pierre

    2009-01-01

    International audience; Conventional maintenance strategies on a single component are being phased out in favour of more predictive maintenance actions. These new kinds of actions are performed in order to control the global performances of the whole industrial system. They are anticipative in nature, which allows a maintenance expert to consider non-already-planned maintenance actions. Two questions naturally emerge: when to perform a predictive maintenance action; how a maintenance expert c...

  9. Machinery prognostics and prognosis oriented maintenance management

    CERN Document Server

    Yan, Jihong

    2014-01-01

    This book gives a complete presentatin of the basic essentials of machinery prognostics and prognosis oriented maintenance management, and takes a look at the cutting-edge discipline of intelligent failure prognosis technologies for condition-based maintenance.  Latest research results and application methods are introduced for signal processing, reliability moelling, deterioration evaluation, residual life prediction and maintenance-optimization as well as applications of these methods.

  10. Tandem mirror next step: remote maintenance

    International Nuclear Information System (INIS)

    Doggett, J.N.; Damm, C.C.; Hanson, C.L.

    1980-01-01

    This study of the next proposed experiment in the Mirror Fusion Program, the Tandem Mirror Next Step (TMNS), has included serious consideration of the maintenance requirements of such a large source of high energy neutrons with its attendant throughput of tritium. Although maintenance will be costly in time and money, our conclusion is that with careful attention to a design for maintenance plan such a device can be reliably operated

  11. Network maintenance

    CERN Multimedia

    GS Department

    2009-01-01

    A site-wide network maintenance operation has been scheduled for Saturday 28 February. Most of the network devices of the general purpose network will be upgraded to a newer software version, in order to improve our network monitoring capabilities. This will result in a series of short (2-5 minutes) random interruptions everywhere on the CERN sites throughout the day. This upgrade will not affect the Computer Centre itself, Building 613, the Technical Network and the LHC experiments, dedicated networks at the pits. For further details of this intervention, please contact Netops by phone 74927 or e-mail mailto:Netops@cern.ch. IT/CS Group

  12. Network maintenance

    CERN Multimedia

    IT Department

    2009-01-01

    A site wide network maintenance has been scheduled for Saturday 28 February. Most of the network devices of the General Purpose network will be upgraded to a newer software version, in order to improve our network monitoring capabilities. This will result in a series of short (2-5 minutes) random interruptions everywhere on the CERN sites along this day. This upgrade will not affect: the Computer centre itself, building 613, the Technical Network and the LHC experiments dedicated networks at the pits. Should you need more details on this intervention, please contact Netops by phone 74927 or email mailto:Netops@cern.ch. IT/CS Group

  13. Automated System Checkout to Support Predictive Maintenance for the Reusable Launch Vehicle

    Science.gov (United States)

    Patterson-Hine, Ann; Deb, Somnath; Kulkarni, Deepak; Wang, Yao; Lau, Sonie (Technical Monitor)

    1998-01-01

    The Propulsion Checkout and Control System (PCCS) is a predictive maintenance software system. The real-time checkout procedures and diagnostics are designed to detect components that need maintenance based on their condition, rather than using more conventional approaches such as scheduled or reliability centered maintenance. Predictive maintenance can reduce turn-around time and cost and increase safety as compared to conventional maintenance approaches. Real-time sensor validation, limit checking, statistical anomaly detection, and failure prediction based on simulation models are employed. Multi-signal models, useful for testability analysis during system design, are used during the operational phase to detect and isolate degraded or failed components. The TEAMS-RT real-time diagnostic engine was developed to utilize the multi-signal models by Qualtech Systems, Inc. Capability of predicting the maintenance condition was successfully demonstrated with a variety of data, from simulation to actual operation on the Integrated Propulsion Technology Demonstrator (IPTD) at Marshall Space Flight Center (MSFC). Playback of IPTD valve actuations for feature recognition updates identified an otherwise undetectable Main Propulsion System 12 inch prevalve degradation. The algorithms were loaded into the Propulsion Checkout and Control System for further development and are the first known application of predictive Integrated Vehicle Health Management to an operational cryogenic testbed. The software performed successfully in real-time, meeting the required performance goal of 1 second cycle time.

  14. Development of divertor remote maintenance system

    Energy Technology Data Exchange (ETDEWEB)

    Takeda, Nobukazu; Oka, Kiyoshi; Akou, Kentaro; Takiguchi, Yuji [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment

    1998-04-01

    The ITER divertor is categorized as a scheduled maintenance component because of extreme heat and particle loads it is exposed to by plasma. It is also highly activated by 14 MeV neutrons. Reliable remote handling equipment and tools are required for divertor maintenance under intense gamma radiation. To facilitate remote maintenance, the divertor is segmented into 60 cassettes, and each cassette weighing about 25 tons and maintained and replaced through four maintenance ports each 90 degrees. Divertor cassettes must be transported toroidally and radially for replacement through maintenance ports. Remote handling involving cassette movers and carriers for toroidal and radial transport has been developed. Under the ITER R and D program, technology critical to divertor cassette maintenance is being developed jointly by Japan, E.U., and U.S. home teams. This paper summarizes divertor remote maintenance design and the status of technology development by the Japan Home Team. (author)

  15. Development of divertor remote maintenance system

    International Nuclear Information System (INIS)

    Takeda, Nobukazu; Oka, Kiyoshi; Akou, Kentaro; Takiguchi, Yuji

    1998-01-01

    The ITER divertor is categorized as a scheduled maintenance component because of extreme heat and particle loads it is exposed to by plasma. It is also highly activated by 14 MeV neutrons. Reliable remote handling equipment and tools are required for divertor maintenance under intense gamma radiation. To facilitate remote maintenance, the divertor is segmented into 60 cassettes, and each cassette weighing about 25 tons and maintained and replaced through four maintenance ports each 90 degrees. Divertor cassettes must be transported toroidally and radially for replacement through maintenance ports. Remote handling involving cassette movers and carriers for toroidal and radial transport has been developed. Under the ITER R and D program, technology critical to divertor cassette maintenance is being developed jointly by Japan, E.U., and U.S. home teams. This paper summarizes divertor remote maintenance design and the status of technology development by the Japan Home Team. (author)

  16. Knowledge engineering thinking of maintenance

    International Nuclear Information System (INIS)

    2007-01-01

    Maintenance optimization problem could not always settled mathematically and was obliged to use quasi-optimum solution with omitting non-formulated limiting condition or neglecting part of optimization object. In such a case knowledge engineering thinking was encouraged. Maintenance of complicated plant and artificial system should be considered from artificial object (equipment/facility hardware and system), technical information and knowledge base, and organizational and human aspect or society and institution. Comprehensive management system in organization and society was necessary not only for assuring integrity of equipment but also for attaining higher performance, reliability and economics of system. For better judgment it was important to share mechanism to make use of more information with organization or whole society. It was required to create database and data mining for knowledge base management system of maintenance. Maintenance was called 'last fortress' to assure quality such as reliability and safety of required function of equipment. Strategic approach to develop maintenance technology under cooperation was considered. Life extension R and D road map was launched in 2005. (T. Tanaka)

  17. Applicability of Operational Research Techniques in CANDU Nuclear Plant Maintenance

    International Nuclear Information System (INIS)

    Doyle, E. Kevin

    2002-01-01

    As previously reported at ICONE 6 in New Orleans, 1996, and ICONE 9 in Niece, 2001, the use of various maintenance optimization techniques at Bruce has lead to cost effective preventive maintenance applications for complex systems. Innovative practices included greatly reducing Reliability Centered Maintenance (RCM) costs while maintaining the accuracy of the analysis. The optimization strategy has undergone further evolution and at the present an Integrated Maintenance Program (IMP) is being put in place. Further cost refinement of the station preventive maintenance strategy whereby decisions are based on statistical analysis of historical failure data is being evaluated. A wide range of Operational Research (OR) literature was reviewed for implementation issues and several encouraging areas were found that will assist in the current effort of evaluating maintenance optimization techniques for nuclear power production. The road ahead is expected to consist first of resolving 25 years of data issues and preserving the data via appropriate knowledge system techniques while post war demographics permit experts to input into the system. Subsequent analytical techniques will emphasize total simplicity to obtain the requisite buy in from Corporate Executives who possibly are not trained in Operational Research. Case studies of containment airlock seal failures are used to illustrate the direct applicability of stochastic processes. Airlocks and transfer chambers were chosen as they have long been known as high maintenance items. Also, the very significant financial consequences of this type of failure will help to focus the attention of Senior Management on the effort. Despite substantial investment in research, improvement in the design of the seal material or configuration has not been achieved beyond the designs completed in the 1980's. Overall, the study showed excellent agreement of the relatively quick stochastic methods with the maintenance programs produced at

  18. A cluster-analytic profiling of heroin-dependent patients based on level, clinical adequacy, and patient-desired adjustment of buprenorphine dosage during buprenorphine-naloxone maintenance treatment in sixteen Spanish centers.

    Science.gov (United States)

    Alcaraz, Saul; González-Saiz, Francisco; Trujols, Joan; Vergara-Moragues, Esperanza; Siñol, Núria; Pérez de Los Cobos, José

    2018-06-01

    Buprenorphine dosage is a crucial factor influencing outcomes of buprenorphine treatment for heroin use disorders. Therefore, the aim of the present study is to identify naturally occurring profiles of heroin-dependent patients regarding individualized management of buprenorphine dosage in clinical practice of buprenorphine-naloxone maintenance treatment. 316 patients receiving buprenorphine-naloxone maintenance treatment were surveyed at 16 Spanish centers during the stabilization phase of this treatment. Patients were grouped using cluster analysis based on three key indicators of buprenorphine dosage management: dose, adequacy according to physician, and adjustment according to patient. The clusters obtained were compared regarding different facets of patient clinical condition. Four clusters were identified and labeled as follows (buprenorphine average dose and percentage of participants in each cluster are given in brackets): "Clinically Adequate and Adjusted to Patient Desired Low Dosage" (2.60 mg/d, 37.05%); "Clinically Adequate and Adjusted to Patient Desired High Dosage" (10.71 mg/d, 29.18%); "Clinically Adequate and Patient Desired Reduction of Low Dosage" (3.38 mg/d, 20.0%); and "Clinically Inadequate and Adjusted to Patient Desired Moderate Dosage" (7.55 mg/d, 13.77%). Compared to patients from the other three clusters, participants in the latter cluster reported more frequent use of heroin and cocaine during last week, lower satisfaction with buprenorphine-naloxone as a medication, higher prevalence of buprenorphine-naloxone adverse effects and poorer psychological adjustment. Our results show notable differences between clusters of heroin-dependent patients regarding buprenorphine dosage management. We also identified a group of patients receiving clinically inadequate buprenorphine dosage, which was related to poorer clinical condition. Copyright © 2018 Elsevier B.V. All rights reserved.

  19. Maintenance optimization for subsea oil pipelines

    International Nuclear Information System (INIS)

    Castanier, Bruno; Rausand, Marvin

    2006-01-01

    In this paper, the classical PF interval model, proposed for reliability centered maintenance, is used to optimize the preventive replacement policy of a subsea oil pipeline. The pipeline is subject to failure modes that may lead to oil release and pollution of the sea. The proposed replacement policy is based on regular condition measurements of the quality of an internal pipeline coating (lining). Holes in the coating will expose the pipe material (steel) to a corrosive environment. It is, therefore, important to identify holes in the coating and take action before the corrosion penetrates the pipe wall. The model proposed in the paper can be used to determine the inspection interval that minimizes the average maintenance cost per time unit. The model formulation is outlined and illustrative examples are solved. The mathematical evaluation of the replacement policy requires numerous assumptions. These assumptions have to be tailored to the specific application. The assumptions and the data provided are included for illustrative purposes to exemplify potential results that may be obtained by using the replacement policy

  20. Plant inspection and maintenance technology

    International Nuclear Information System (INIS)

    Miyahara, Masatoshi; Kanazawa, Masafumi

    1995-01-01

    The article reports on information systems and related tools that support routine inspection and preventive maintenance activities, which contribute to safer plant operation and increase plant operating duty. Tools include the Mitsubishi Electric Reliability and Availability Upgrade Program-Nuclear (MELRAP-N), which supports the general evolution of industry operating experiences, periodic component replacement management, management of discontinued and modified components, periodic inspection item management, and periodic inspection workplace management. The article also introduces a comprehensive preventive maintenance management system currently under development. (author)

  1. Development of a Reliability Program approach to assuring operational nuclear 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 used in other high technology industries is being formulated for potential application in the nuclear power industry. Research findings are discussed. The reliability methods employed under NASA and military direction, commercial airline and related FAA programs were surveyed with several reliability concepts (e.g., quantitative reliability goals, reliability centered maintenance) appearing to be directly transferable. Other tasks in the RP development effort involved the benchmarking and evaluation of the existing nuclear regulations and practices relevant to safety/reliability integration. A review of current risk-dominant issues was also conducted using results from existing probabilistic risk assessment studies. The ongoing RP development tasks have concentrated on defining a RP for the operating phase of a nuclear plant's lifecycle. The RP approach incorporates safety systems risk/reliability analysis and performance monitoring activities with dedicated tasks that integrate these activities with operating, 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 RP

  2. Inter-rater Reliability on the Individual Music-Centered Assessment Profile for Neurodevelopmental Disorders (IMCAP-ND) for autism spectrum disorder. Nordic Journal of Music Therapy

    DEFF Research Database (Denmark)

    Carpente, John; Gattino, Gustavo

    2018-01-01

    Background: The Individual Music-Centered Assessment Profile for Neurodevelopmental Disorders (IMCAP-ND) is an evaluation instrument made up of three criterion-referenced rating scales designed to examine how clients perceive, interpret, and make music with the therapist while participating...

  3. 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

  4. Electric motor predictive and preventive maintenance guide

    International Nuclear Information System (INIS)

    Oliver, J.A.

    1992-07-01

    Electric motor performance is vital to the reliable and efficient operation of power plants. The failure of one or more critical motors could cause lost capacity and excessive repair and maintenance cost. However, existing maintenance recommendations proposed by vendors for electric motors have sometimes encouraged many overly conservative maintenance practices. These practices have lead to excessive maintenance activities and costs which have provided no extra margin of operability. EPRI has sponsored RP2814-35 to develop a guide which provides power plants with information and guidance for establishing an effective maintenance program which will aid in preventing unexpected motor failures and assist in planning motor maintenance efforts. The guide includes a technical description which summarizes technical data relative to the four basic types of motors and their components in general use in power plants. The significant causes of motor failures are investigated and described in detail and methods to optimize service life and minimize maintenance cost through appropriate preventive maintenance and conditioning program are presented. This guide provides a foundation for an effective electric motor maintenance program and simplifies the selection of predictive and preventive maintenance tasks. Its use will enable maintenance personnel in nuclear and fossil plants to plan motor repairs during scheduled outages and avoid costly unexpected failures

  5. Pacific Northwest Laboratory Maintenance Implementation plan

    International Nuclear Information System (INIS)

    Bright, J.D.

    1992-06-01

    This Maintenance Implementation plan has been developed for Pacific Northwest Laboratory's (PNL) Nuclear Facilities: 306W, 324, 325, 327 and 329NMF. It is based on a graded approach, self-assessment of the existing maintenance program(s) per the requirements specified by US Department of Energy (DOE) Order 4330.4A, Chapter II, Change number-sign 3. The results of this assessment were evaluated to determine needed improvements in PNL Craft Services' current maintenance program. The objective of this implementation plan is to provide baseline information for compliance to the DOE 4330.4A, and for needed improvements. The prime consideration in applying a graded approach to the Order has been to maintain safe and reliable operations, environmental compliance, safeguards and security, programmatic mission, facility preservation, and/or other facility-specific requirements. Using the results of the self-assessment, PNL has selected nine of the 18 elements of the Maintenance Program defined by DOE Order 4330.4A for improvement. The elements selected for improvement are Training and Qualification of Maintenance Personnel; Maintenance Procedures; Planning, Scheduling, and Coordination of Maintenance; Control of Maintenance Activities; Post-Maintenance Testing; Facility Condition Inspection; Management Involvement; Maintenance History; and Additional Maintenance Requirements. Based upon graded approach and current funding, those elements considered most important have been selected as goals for earliest compliance. Commitment dates for these elements have been established for compliance. The remaining elements of noncompliance will be targeted for implementation during later budget periods

  6. Concurrent validity and reliability of using ground reaction force and center of pressure parameters in the determination of leg movement initiation during single leg lift.

    Science.gov (United States)

    Aldabe, Daniela; de Castro, Marcelo Peduzzi; Milosavljevic, Stephan; Bussey, Melanie Dawn

    2016-09-01

    Postural adjustment evaluations during single leg lift requires the initiation of heel lift (T1) identification. T1 measured by means of motion analyses system is the most reliable approach. However, this method involves considerable workspace, expensive cameras, and time processing data and setting up laboratory. The use of ground reaction forces (GRF) and centre of pressure (COP) data is an alternative method as its data processing and setting up is less time consuming. Further, kinetic data is normally collected using frequency samples higher than 1000Hz whereas kinematic data are commonly captured using 50-200Hz. This study describes the concurrent-validity and reliability of GRF and COP measurements in determining T1, using a motion analysis system as reference standard. Kinematic and kinetic data during single leg lift were collected from ten participants. GRF and COP data were collected using one and two force plates. Displacement of a single heel marker was captured by means of ten Vicon(©) cameras. Kinetic and kinematic data were collected using a sample frequency of 1000Hz. Data were analysed in two stages: identification of key events in the kinetic data, and assessing concurrent validity of T1 based on the chosen key events with T1 provided by the kinematic data. The key event presenting the least systematic bias, along with a narrow 95% CI and limits of agreement against the reference standard T1, was the Baseline COPy event. Baseline COPy event was obtained using one force plate and presented excellent between-tester reliability. Copyright © 2016 Elsevier B.V. All rights reserved.

  7. 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)

  8. 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...

  9. 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

  10. Two Different Maintenance Strategies in the Hospital Environment: Preventive Maintenance for Older Technology Devices and Predictive Maintenance for Newer High-Tech Devices.

    Science.gov (United States)

    Sezdi, Mana

    2016-01-01

    A maintenance program generated through the consideration of characteristics and failures of medical equipment is an important component of technology management. However, older technology devices and newer high-tech devices cannot be efficiently managed using the same strategies because of their different characteristics. This study aimed to generate a maintenance program comprising two different strategies to increase the efficiency of device management: preventive maintenance for older technology devices and predictive maintenance for newer high-tech devices. For preventive maintenance development, 589 older technology devices were subjected to performance verification and safety testing (PVST). For predictive maintenance development, the manufacturers' recommendations were used for 134 high-tech devices. These strategies were evaluated in terms of device reliability. This study recommends the use of two different maintenance strategies for old and new devices at hospitals in developing countries. Thus, older technology devices that applied only corrective maintenance will be included in maintenance like high-tech devices.

  11. Maintenance Business Plans.

    Science.gov (United States)

    Adams, Matt

    2002-01-01

    Discusses maintenance business plans, statements which provide accountability for facilities maintenance organizations' considerable budgets. Discusses the plan's components: statement of plan objectives, macro and detailed description of the facility assets, maintenance function descriptions, description of key performance indicators, milestone…

  12. Maintenance Management Update.

    Science.gov (United States)

    Sternloff, Robert E.

    1987-01-01

    Current trends in park maintenance are overviewed, including maintenance impact statements, avoidance of cost through efficient use and national resource conservation, horticultural accomplishments that influence maintenance management, and vandalism prevention. (CB)

  13. Design for maintenance during operation

    International Nuclear Information System (INIS)

    Barton, P.H.; Lyerly, H.D.

    1976-01-01

    Design of a nuclear power plant for safe, reliable and efficient operation involves much more than theory, regulations, regulatory guides, procedures, inspectors, and even quality assurance. It also involves a full knowledge and understanding of the activities which must be carried out to operate and maintain the plant. It must be remembered that a nuclear power plant is different from fossil designs and the designer must constantly keep in mind that access by people to every component is required for maintenance

  14. Maintenance and management system

    International Nuclear Information System (INIS)

    Ando, Yasumasa.

    1992-01-01

    Since highly reliable operation is required in a nuclear power plant, monitoring during operation and periodical inspection are conducted carefully. The present invention provides maintenance and management systems for providing an aid so that these systems are combined effectively and operated rationally based on unified information management. That is, the system contains data bases comprising information for the design of the equipments and pipelines of a plant, information for the exchange of equipment parts, information for the history of plant operation, information for the monitoring and inspection, and information for the management of repair operation. In addition, it has an equipment part history management sub-system for managing equipment part exchange information, an operation history management sub-system for managing the operation state of the plant, an operation history management sub-system for managing equipment monitoring inspection data and operation management sub-system for managing periodical inspection/ repairing operation. These sub-systems are collectively combined to manage the maintenance and management jobs of the plant unitarily. (I.S.)

  15. Maintenance Centered Service Parts Inventory Control

    NARCIS (Netherlands)

    W.L. van Jaarsveld (Willem)

    2013-01-01

    textabstractHigh-tech capital goods enable the production of many services and articles that have become a part of our daily lives. Examples include the refineries that produce the gasoline we put in our cars, the photolithography systems that enable the production of the chips in our cell phones

  16. Condition based maintenance pilot projects at Pickering ND

    International Nuclear Information System (INIS)

    Zemdegs, R.T.

    1995-01-01

    Ontario Hydro has recognized that the approaches to maintenance have undergone significant changes to the past decades. The traditional break down maintenance approach has been replaced by preventative maintenance and more recently, by condition based maintenance. The nuclear plants of Ontario Hydro have evaluated on a number of alternative programs to improve their maintenance effectiveness and to reduce costs, including Reliability Centred Maintenance (RCM), call-up review, component-based PM programs, analysis of failure history and so on. Pickering ND (nuclear division) and Ontario Hydro's Nuclear Technologies Services Division, have embarked on a Condition Based Maintenance pilot project to address the above issues as a breakthrough solution for smarter maintenance. The Condition Based Maintenance pilot project will demonstrate an end-to-end process utilizing a Reliability Centred Maintenance structured approach to re-engineer and redefine the existing maintenance programs. The project emphasizes on-condition maintenance where justified, and utilizes an information management tool to provide the required records keeping and analysis infrastructure. This paper briefly describes the planned maintenance model at Pickering ND used to guide the CBM pilot, and an overview of the methodology used to develop on-condition equipment indicators as part of a re-engineered maintenance plan

  17. Value maximizing maintenance policies under general repair

    International Nuclear Information System (INIS)

    Marais, Karen B.

    2013-01-01

    One class of maintenance optimization problems considers the notion of general repair maintenance policies where systems are repaired or replaced on failure. In each case the optimality is based on minimizing the total maintenance cost of the system. These cost-centric optimizations ignore the value dimension of maintenance and can lead to maintenance strategies that do not maximize system value. This paper applies these ideas to the general repair optimization problem using a semi-Markov decision process, discounted cash flow techniques, and dynamic programming to identify the value-optimal actions for any given time and system condition. The impact of several parameters on maintenance strategy, such as operating cost and revenue, system failure characteristics, repair and replacement costs, and the planning time horizon, is explored. This approach provides a quantitative basis on which to base maintenance strategy decisions that contribute to system value. These decisions are different from those suggested by traditional cost-based approaches. The results show (1) how the optimal action for a given time and condition changes as replacement and repair costs change, and identifies the point at which these costs become too high for profitable system operation; (2) that for shorter planning horizons it is better to repair, since there is no time to reap the benefits of increased operating profit and reliability; (3) how the value-optimal maintenance policy is affected by the system's failure characteristics, and hence whether it is worthwhile to invest in higher reliability; and (4) the impact of the repair level on the optimal maintenance policy. -- Highlights: •Provides a quantitative basis for maintenance strategy decisions that contribute to system value. •Shows how the optimal action for a given condition changes as replacement and repair costs change. •Shows how the optimal policy is affected by the system's failure characteristics. •Shows when it is

  18. 9th International conference on CANDU maintenance

    International Nuclear Information System (INIS)

    2011-01-01

    The 9th International Conference on CANDU Maintenance was held in Toronto, Ontario, Canada on December 4-6, 2011. The conference focused on Nuclear plant reliability and maintenance. Equipment reliability is a critical factor in achieving safe and reliable Nuclear Power Plant operations for many reasons. For one it reduces the challenges upon the operating staff and allows station personnel to 'go on the offence' instead of having to play defense in a reactive mode. Plant reliability ensures that there is time to study the issues in detail and develop solutions for long-term success. Let us not forget that the owner carries the burden of demonstrating the return on investment, and plant reliability goes a long way in helping to make the case for plant life extension. A good reputation for plant reliability provides the public capital necessary to build confidence and facilitate the licensing process. The proceedings papers and presentations given at the 9th International Conference on Candu Maintenance covered topics that include: Managing Worker; Radiation Dose; Full Life Cycle Management; Managing Maintenance Refurbishment; Designing for Maintainability; Inspection Techniques; and, Mitigating Degradation.

  19. Efficacy, Reliability, and Safety of Completely Autologous Fibrin Glue in Neurosurgical Procedures: Single-Center Retrospective Large-Number Case Study.

    Science.gov (United States)

    Nakayama, Noriyuki; Yano, Hirohito; Egashira, Yusuke; Enomoto, Yukiko; Ohe, Naoyuki; Kanemura, Nobuhiro; Kitagawa, Junichi; Iwama, Toru

    2018-01-01

    Commercially available fibrin glue (Com-FG), which is used commonly worldwide, is produced with pooled human plasma from multiple donors. However, it has added bovine aprotinin, which involves the risk of infection, allogenic immunity, and allergic reactions. We evaluate the efficacy, reliability, and safety of completely autologous fibrin glue (CAFG). From August 2014 to February 2016, prospective data were collected and analyzed from 153 patients. CAFG was prepared with the CryoSeal System using autologous blood and was applied during neurosurgical procedures. Using CAFG-soaked oxidized regenerated cellulose and/or polyglycolic acid sheets, we performed a pinpoint hemostasis, transposed the offending vessels in a microvascular decompression, and covered the dural incision to prevent cerebrospinal fluid leakage. The CryoSeal System had generated up to a mean of 4.51 mL (range, 3.0-8.4 mL) of CAFG from 400 mL autologous blood. Com-FG products were not used in our procedures. Only 6 patients required an additional allogeneic blood transfusion. The hemostatic effective rate was 96.1% (147 of 153 patients). Only 1 patient who received transsphenoidal surgery for a pituitary adenoma presented with the complication of delayed postoperative cerebrospinal fluid leakage (0.65%). No patient developed allergic reactions or systemic complications associated with the use of CAFG. CAFG effectively provides hemostatic, adhesive, and safety performance. The timing and three-dimensional shape of CAFG-soaked oxidized regenerated cellulose and/or polyglycolic acid sheets solidification can be controlled with slow fibrin formation. The cost to prepare CAFG is similar compared with Com-FG products, and it can therefore be easily used at most institutions. Copyright © 2017 Elsevier Inc. All rights reserved.

  20. Optimum Maintenance Strategies for Highway Bridges

    DEFF Research Database (Denmark)

    Frangopol, Dan M.; Thoft-Christensen, Palle; Das, Parag C.

    As bridges become older and maintenance costs become higher, transportation agencies are facing challenges related to implementation of optimal bridge management programs based on life cycle cost considerations. A reliability-based approach is necessary to find optimal solutions based on minimum...... expected life-cycle costs or maximum life-cycle benefits. This is because many maintenance activities can be associated with significant costs, but their effects on bridge safety can be minor. In this paper, the program of an investigation on optimum maintenance strategies for different bridge types...... is described. The end result of this investigation will be a general reliability-based framework to be used by the UK Highways Agency in order to plan optimal strategies for the maintenance of its bridge network so as to optimize whole-life costs....

  1. Adaptation and Implementation of Predictive Maintenance Technique with Nondestructive Testing for Power Plants

    International Nuclear Information System (INIS)

    Jung, Gye Jo; Jung, Nam Gun

    2010-01-01

    Many forces are pressuring utilities to reduce operating and maintenance costs without cutting back on reliability or availability. Many utility managers are re-evaluating maintenance strategies to meet these demands. To utilities how to reduce maintenance costs and extent the effective operating life of equipment, predictive maintenance technique can be adapted. Predictive maintenance had three types program which are in-house program, engineering company program and mixed program. We can approach successful predictive maintenance program with 'smart trust' concept

  2. 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

  3. 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.

  4. A Situational Maintenance Model

    DEFF Research Database (Denmark)

    Luxhoj, James T.; Thorsteinsson, Uffe; Riis, Jens Ove

    1997-01-01

    An overview of trend in maintenance management and presentation of a situational model and an analytical tools for identification of managerial efforts in maintenance.......An overview of trend in maintenance management and presentation of a situational model and an analytical tools for identification of managerial efforts in maintenance....

  5. Maintenance in nuclear production power plants

    International Nuclear Information System (INIS)

    Lozano, J. M.

    2010-01-01

    This article highlights the importance and quality of maintenance in the complete phases of development, in a sector which has been often questioned by the public opinion, and that is always subject to national and international standards. The aim of maintenance is to guarantee the production of electric power in a reliable, safe, economic and friendly environmentally way, assuring a long-term production. (Author)

  6. Maintenance viewpoint of a successful reactor program

    International Nuclear Information System (INIS)

    Moffitt, W.C.; Grygiel, M.L.

    1984-05-01

    As the Operating and Support staffs of the FFTF organization have gained experience, the plant reliability and capacity factors have shown a steadily improving trend. The plant capacity factor for Cycle 4 was 99.5%. It is the purpose of this report to describe the evolution of the maintenance organization at the FFTF site from a general support organization to a technically proficient organization playing a major role in planning and performance of plant maintenance evolutions

  7. A HUMAN RELIABILITY-CENTERED APPROACH TO THE DEVELOPMENT OF JOB AIDS FOR REVIEWERS OF MEDICAL DEVICES THAT USE RADIOLOGICAL BYPRODUCT MATERIALS.

    Energy Technology Data Exchange (ETDEWEB)

    COOPER, S.E.; BROWN, W.S.; WREATHALL, J.

    2005-02-02

    The U.S. Nuclear Regulatory Commission (NRC) is engaged in an initiative to risk-inform the regulation of byproduct materials. Operating experience indicates that human actions play a dominant role in most of the activities involving byproduct materials, which are radioactive materials other than those used in nuclear power plants or in weapons production, primarily for medical or industrial purposes. The overall risk of these activities is strongly influenced by human performance. Hence, an improved understanding of human error, its causes and contexts, and human reliability analysis (HRA) is important in risk-informing the regulation of these activities. The development of the human performance job aids was undertaken by stages, with frequent interaction with the prospective users. First, potentially risk significant human actions were identified based on reviews of available risk studies for byproduct material applications and of descriptions of events for byproduct materials applications that involved potentially significant human actions. Applications from the medical and the industrial domains were sampled. Next, the specific needs of the expected users of the human performance-related capabilities were determined. To do this, NRC headquarters and region staff were interviewed to identify the types of activities (e.g., license reviews, inspections, event assessments) that need HRA support and the form in which such support might best be offered. Because the range of byproduct uses regulated by NRC is so broad, it was decided that initial development of knowledge and tools would be undertaken in the context of a specific use of byproduct material, which was selected in consultation with NRC staff. Based on needs of NRC staff and the human performance related characteristics of the context chosen, knowledge resources were then compiled to support consideration of human performance issues related to the regulation of byproduct materials. Finally, with

  8. A HUMAN RELIABILITY-CENTERED APPROACH TO THE DEVELOPMENT OF JOB AIDS FOR REVIEWERS OF MEDICAL DEVICES THAT USE RADIOLOGICAL BYPRODUCT MATERIALS

    International Nuclear Information System (INIS)

    COOPER, S.E.; BROWN, W.S.; WREATHALL, J.

    2005-01-01

    The U.S. Nuclear Regulatory Commission (NRC) is engaged in an initiative to risk-inform the regulation of byproduct materials. Operating experience indicates that human actions play a dominant role in most of the activities involving byproduct materials, which are radioactive materials other than those used in nuclear power plants or in weapons production, primarily for medical or industrial purposes. The overall risk of these activities is strongly influenced by human performance. Hence, an improved understanding of human error, its causes and contexts, and human reliability analysis (HRA) is important in risk-informing the regulation of these activities. The development of the human performance job aids was undertaken by stages, with frequent interaction with the prospective users. First, potentially risk significant human actions were identified based on reviews of available risk studies for byproduct material applications and of descriptions of events for byproduct materials applications that involved potentially significant human actions. Applications from the medical and the industrial domains were sampled. Next, the specific needs of the expected users of the human performance-related capabilities were determined. To do this, NRC headquarters and region staff were interviewed to identify the types of activities (e.g., license reviews, inspections, event assessments) that need HRA support and the form in which such support might best be offered. Because the range of byproduct uses regulated by NRC is so broad, it was decided that initial development of knowledge and tools would be undertaken in the context of a specific use of byproduct material, which was selected in consultation with NRC staff. Based on needs of NRC staff and the human performance related characteristics of the context chosen, knowledge resources were then compiled to support consideration of human performance issues related to the regulation of byproduct materials. Finally, with

  9. High Availability Applications for NOMADS at the NOAA Web Operations Center Aimed at Providing Reliable Real Time Access to Operational Model Data

    Science.gov (United States)

    Alpert, J. C.; Rutledge, G.; Wang, J.; Freeman, P.; Kang, C. Y.

    2009-05-01

    The NOAA Operational Modeling Archive Distribution System (NOMADS) is now delivering high availability services as part of NOAA's official real time data dissemination at its Web Operations Center (WOC). The WOC is a web service used by all organizational units in NOAA and acts as a data repository where public information can be posted to a secure and scalable content server. A goal is to foster collaborations among the research and education communities, value added retailers, and public access for science and development efforts aimed at advancing modeling and GEO-related tasks. The services used to access the operational model data output are the Open-source Project for a Network Data Access Protocol (OPeNDAP), implemented with the Grid Analysis and Display System (GrADS) Data Server (GDS), and applications for slicing, dicing and area sub-setting the large matrix of real time model data holdings. This approach insures an efficient use of computer resources because users transmit/receive only the data necessary for their tasks including metadata. Data sets served in this way with a high availability server offer vast possibilities for the creation of new products for value added retailers and the scientific community. New applications to access data and observations for verification of gridded model output, and progress toward integration with access to conventional and non-conventional observations will be discussed. We will demonstrate how users can use NOMADS services to repackage area subsets either using repackaging of GRIB2 files, or values selected by ensemble component, (forecast) time, vertical levels, global horizontal location, and by variable, virtually a 6- Dimensional analysis services across the internet.

  10. 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)

  11. Configuration management of on-line maintenance

    International Nuclear Information System (INIS)

    Grantom, C.R.

    1996-01-01

    Maintenance activities are performed on station equipment to ensure continued safe and reliable performance. Equipment reliability is thereby improved, resulting in greater confidence that the component will be capable of performing its intended (safety) function. Probabilistic Safety Assessments (PSAs) consider equipment reliability and availability to calculate Core Damage Frequency (CDF) and other risk-related values. Since maintenance activities are included in PSA analyses, the effect of equipment outages on CDF can be analyzed. Results from these types of studies can be scaled to reflect different time periods and show the time-dependent impact of planned equipment outages on CDF. These time-dependent impacts on CDF are graphically presented and referred to as ''risk profiles''. Risk profiles are being successfully used at the South Texas Project (STP) to plan preventive maintenance activities and to assess the impact of unplanned maintenance activities on plant safety. At STP, planned maintenance activities are scheduled to minimize the risk impact of unavailable equipment and to prevent the Occurrence of undesirable plant configurations. The features of the risk profiles used at STP enable the evaluation of both work scope and duration of maintenance activities to be evaluated. This is possible since the risk profile illustrates both instantaneous CDF effects and cumulative impacts to CDF

  12. Probabilistic approach to rationalization of plants maintenance

    International Nuclear Information System (INIS)

    Kasai, Masao; Notoya, Junichi; Uchimoto, Tetsuya; Miya, Kenzo

    2001-01-01

    Since there are a lot of equipments in large plants, their safety and reliability cannot be kept as high level as designed without maintenance activities. Then preventive maintenance is intensively executed in some large plants. However, it will be inefficient to perform the preventive maintenance blindly. To make maintenance activities effective, it is essential to identify the critical equipments influencing plant safety and/or reliability and carry out the maintenance by focusing attentions on these equipments. It needs quantitative analyses to identify the critical equipments based on the data of failure rates. However, complete data set of failure rates cannot necessarily be available for some plants such as nuclear power plants. In this study, we carry out the reliability analysis for generic LNG plant and calculate various quantitative risk importance measures for each equipment. We propose rather qualitative representations for some quantitative measures, considering the situation without complete data set and conclude that it is possible to rationalize maintenance procedure by using these rather qualitative measures, though the level of rationalization is of course limited. (author)

  13. Tele-maintenance 'intelligent' system for technical plants result management

    International Nuclear Information System (INIS)

    Concetti, Massimo; Cuccioletta, Roberto; Fedele, Lorenzo; Mercuri, Giampiero

    2009-01-01

    The management of technical plant for productivity and safety is generally a complex activity, particularly when many plants distributed in the territory are considered (i.e. the more and more frequent case of outsourced plants maintenance by specialized companies), granted quality and cost results are required (i.e. the case of some rather innovative contract solutions) and the technology involved is heterogeneous and innovative (i.e. electro-mechanical plants). In order to efficiently achieve the above aims an 'intelligent' maintenance-management system for the distant monitoring and controlling by a remote control center has been developed. The so-called GrAMS (granted availability management system) system is conceived to give to organizations involved in technical-industrial plants management the possibility to tend to a 'well-known availability' and 'zero-failures' management. In particular, this study deals with the diagnostic aspects and safety level of technical plants (such as elevators, thermo-technical plants, etc.), and with the involvement of ad hoc designed software analysis tools based on neural networks and reliability indicators. Part of the research dealing with the tele-maintenance intelligent system has been financed by the Italian High Institute for Safety (ISPESL) and led to the development of a pre-industrial prototype whose realization and testing is here described

  14. Maintenance Approaches for Different Production Methods

    Directory of Open Access Journals (Sweden)

    Mungani, Dzivhuluwani Simon

    2013-11-01

    Full Text Available Various production methods are used in industry to manufacture or produce a variety of products needed by industry and consumers. The nature of a product determines which production method is most suitable or cost-effective. A continuous process is typically used to produce large volumes of liquids or gases. Batch processing is often used for small volumes, such as pharmaceutical products. This paper discusses a research project to determine the relationship between maintenance approaches and production methods. A survey was done to determine to what extent three maintenance approaches reliability-centred maintenance (RCM, total productive maintenance (TPM, and business-centred maintenance (BCM are used for three different processing methods (continuous process, batch process, and a production line method.

  15. Cognitive and organizational ergonomics in the transition of the new integrated center of control of an oil refinery: human reliability and administration of changes.

    Science.gov (United States)

    Bau, Lucy M S; Puquirre, Magda S E S; Buso, Sandro A; Ogasawara, Érika L; Marcon Passero, Carolina R; Bianchi, Marcos C

    2012-01-01

    The conception of a product is closely tied to its adaptation level to the users. In this view, designers are increasingly oriented to survey the needs and features of the users. This paper aims at developing a diagnosis of employees working in high-complexity activities in a petrochemical company, in light of the physical and operating changes in the Integrated Center of Control; assessing the reception sensibility to changes; assessing the cognitive pattern of the group; and making suggestions that might eliminate or minimize the difficulties in the transition process of the change, in order to reduce the adaptation period. The field of study comprised 111 production, transfer and storage operators, forming 5 groups of desktop activities. The stages of the study followed the following flow: survey of the prescribed tasks and organizational structure; Concentrated Attention test; application of the Work and Disease Risks Inventory (ITRA, Portuguese acronym); and structured psychological interview. The ITRA results pointed to a serious cognitive cost (3.83) for all five groups, this being the largest intervention focus. The items: division of task contents (3.52), social professional relationships (2.93), quality of the physical environment (2.91), physical cost (3.24), emotional cost (2.71), freedom of expression (3.77), professional fulfillment (3.41); experience and suffering (2.75), lack of recognition (2.18) and physical injuries (2.07) were considered critical. Meanwhile, social damages (1.64) and psychological injuries (1.35) are bearable. As to the Concentrated Attention test, most workers registered average level. In the individual interviews, workers showed that larger involvement in the process of physical, organizational and operational change in the desktops and on field works was required, as well as the follow up of implementations, so as to reduce the adaptation process and prevent rework (furniture, equipment, noise, form of communication with the

  16. Reliability Considerations for the Operation of Large Accelerator User Facilities

    CERN Document Server

    Willeke, F.J.

    2016-01-01

    The lecture provides an overview of considerations relevant for achieving highly reliable operation of accelerator based user facilities. The article starts with an overview of statistical reliability formalism which is followed by high reliability design considerations with examples. The article closes with operational aspects of high reliability such as preventive maintenance and spares inventory.

  17. 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.)

  18. Maintenance Optimization of High Voltage Substation Model

    Directory of Open Access Journals (Sweden)

    Radim Bris

    2008-01-01

    Full Text Available The real system from practice is selected for optimization purpose in this paper. We describe the real scheme of a high voltage (HV substation in different work states. Model scheme of the HV substation 22 kV is demonstrated within the paper. The scheme serves as input model scheme for the maintenance optimization. The input reliability and cost parameters of all components are given: the preventive and corrective maintenance costs, the actual maintenance period (being optimized, the failure rate and mean time to repair - MTTR.

  19. Comparative evaluation of remote maintenance schemes for fusion DEMO reactor

    Energy Technology Data Exchange (ETDEWEB)

    Utoh, Hiroyasu, E-mail: uto.hiroyasu@jaea.go.jp; Tobita, Kenji; Someya, Youji; Asakura, Nobuyuki; Sakamoto, Yoshiteru; Hoshino, Kazuo; Nakamura, Makoto

    2015-10-15

    Highlights: • Various remote maintenance schemes for DEMO were comparatively assessed based on requirements for DEMO remote maintenance. • The banana shape segment transport using all vertical maintenance ports would be more probable DEMO reactor maintenance scheme. • The key engineering issues are in-vessel transferring mechanism of segment, pipe connection and conducting shell design for plasma vertical stability. - Abstract: Maintenance schemes are one of the critical issues in DEMO design, significantly affecting the configuration of in-vessel components, the size of toroidal field (TF) coil, the arrangement of poloidal field (PF) coils, reactor building, hot cell and so forth. Therefore, the maintenance schemes should satisfy many design requirements and criteria to assure reliable and safe plant operation and to attain reasonable plant availability. The plant availability depends on reliability of remote maintenance scheme, inspection of pipe connection and plasma operation. In this paper, various remote maintenance schemes for DEMO were comparatively assessed based on requirements for DEMO remote maintenance. From the view points of the reliability of inspection on hot cell, TF coil size, stored energy of PF coil and portability of segment, the banana shape segment transport using all vertical maintenance ports would be more probable DEMO reactor maintenance scheme, and it has key engineering issues such as in-vessel transferring mechanism of segment, pipe connection and conducting shell design for plasma vertical stability.

  20. Comparative evaluation of remote maintenance schemes for fusion DEMO reactor

    International Nuclear Information System (INIS)

    Utoh, Hiroyasu; Tobita, Kenji; Someya, Youji; Asakura, Nobuyuki; Sakamoto, Yoshiteru; Hoshino, Kazuo; Nakamura, Makoto

    2015-01-01

    Highlights: • Various remote maintenance schemes for DEMO were comparatively assessed based on requirements for DEMO remote maintenance. • The banana shape segment transport using all vertical maintenance ports would be more probable DEMO reactor maintenance scheme. • The key engineering issues are in-vessel transferring mechanism of segment, pipe connection and conducting shell design for plasma vertical stability. - Abstract: Maintenance schemes are one of the critical issues in DEMO design, significantly affecting the configuration of in-vessel components, the size of toroidal field (TF) coil, the arrangement of poloidal field (PF) coils, reactor building, hot cell and so forth. Therefore, the maintenance schemes should satisfy many design requirements and criteria to assure reliable and safe plant operation and to attain reasonable plant availability. The plant availability depends on reliability of remote maintenance scheme, inspection of pipe connection and plasma operation. In this paper, various remote maintenance schemes for DEMO were comparatively assessed based on requirements for DEMO remote maintenance. From the view points of the reliability of inspection on hot cell, TF coil size, stored energy of PF coil and portability of segment, the banana shape segment transport using all vertical maintenance ports would be more probable DEMO reactor maintenance scheme, and it has key engineering issues such as in-vessel transferring mechanism of segment, pipe connection and conducting shell design for plasma vertical stability.

  1. Maintenance proficiency evaluation test bank

    International Nuclear Information System (INIS)

    Maier, Loran

    2003-01-01

    The Maintenance Proficiency Evaluation Test Bank (MPETB) is an Electric Power Research Institute- (EPRJ-) operated, utility-sponsored means of developing, maintaining, and disseminating secure, high-quality written and performance maintenance proficiency tests. EPRTs charter is to ensure that all tests and test items that go into the Test Bank have been validated, screened for reliability, and evaluated to high standards of psychometric excellence. Proficiency tests of maintenance personnel.(mechanics, electricians, and instrumentation and control [I and C] technicians) are most often used to determine if an experienced employee is capable of performing maintenance tasks without further training. Such tests provide objective evidence for decisions to exempt an employee from what, for the employee, is unnecessary training. This leads to considerable savings in training costs and increased productivity because supervisors can assign personnel to tasks at which their competence is proven. The ultimate objective of proficiency evaluation is to ensure that qualified maintenance personnel are available to meet the maintenance requirements of the plant Numerous task-specific MPE tests (both written and performance) have been developed and validated using the EPRI MPE methodology by the utilities participating in the MPETB project A task-specific MPE consists of a multiple-choice written examination and a multi-step performance evaluation that can be used to assess an individual's present knowledge and skill level for a given maintenance task. The MPETB contains MPEs and test items for the mechanical, electrical, and I and C classifications that are readily available to participating utilities. Presently, utilities are placing emphasis on developing MPEs to evaluate outage-related maintenance tasks that demonstrate the competency and qualifications of plant and contractor personnel before the start of outage work. Utilities are also using the MPE methodology and process to

  2. Support to NPP operation and maintenance technology risk management. A concept for establishing criteria and procedure for the selection of components with respect to their importance. Stage 3.1. NPP equipment reliability management

    International Nuclear Information System (INIS)

    Stvan, F.

    2003-12-01

    A proposal was developed for a procedure using the deterministic approach to the assessment of components from the operational point of view and other aspects that cannot be directly and readily quantified and of the probabilistic approach for the assessment of component importance with respect to nuclear safety. A specific PSA study performed for the Dukovany NPP was employed. The structure of the report is as follows: (1) Aspects of component selection; (2) Introductory procedure; (3) Criteria for the selection of components with respect to their importance (4) Assessing the priority of use of the assets - effect on production, safety, and profit; (5) Assessment of the risk aspect of the assets - effect on major processes; (6) Assessment of the level of use of the assets; (7) Assessment of the structure of the assets - optimal structure for maintenance in relation to the major processes; (8) Assessment of the criteria for estimating the importance of the components; (9) Probabilistic assessment of importance from the safety aspect by means of PSA; and (10) Deterministic assessment of importance from the safety aspect. (P.A.)

  3. A comprehensive approach to RCM-based preventive maintenance program development

    International Nuclear Information System (INIS)

    Hall, B.E.; Davis, T.; Pennington, A.J.

    1988-01-01

    In late 1986, Public Service Electric and Gas Company (PSE ampersand G) concluded that to support its vision and strategic planning it would be necessary to develop a consistent approach to maintenance for all nuclear units at the artificial island. General Physics Corporation was selected to lead a consultant team to support full-scale development of a preventive maintenance (PM) program for Salem and Hope Creek generating stations based on a reliability-centered maintenance (RCM) approach. RCM was selected because it represents a systematic approach to developing a PM program that provides a logical, consistent, and traceable methodology and produces a well-documented engineering basis for the program. Early in 1987, primary objectives for the PM program were defined. The Phase I tasks addressed key programmatic areas such as maintenance philosophy, procedures, condition monitoring, performance trending, equipment failure data base, ogranization, PM program effectiveness evaluation, RCM process, reliability/availability modeling, information management, training, spare parts, software/hardware, and commitments. Phase I of the PM program development project was completed in January 1988. Highlights of the Phase I work and the PM program manual are described

  4. The Structured Interview & Scoring Tool-Massachusetts Alzheimer's Disease Research Center (SIST-M): development, reliability, and cross-sectional validation of a brief structured clinical dementia rating interview.

    Science.gov (United States)

    Okereke, Olivia I; Copeland, Maura; Hyman, Bradley T; Wanggaard, Taylor; Albert, Marilyn S; Blacker, Deborah

    2011-03-01

    The Clinical Dementia Rating (CDR) and CDR Sum-of-Boxes can be used to grade mild but clinically important cognitive symptoms of Alzheimer disease. However, sensitive clinical interview formats are lengthy. To develop a brief instrument for obtaining CDR scores and to assess its reliability and cross-sectional validity. Using legacy data from expanded interviews conducted among 347 community-dwelling older adults in a longitudinal study, we identified 60 questions (from a possible 131) about cognitive functioning in daily life using clinical judgment, inter-item correlations, and principal components analysis. Items were selected in 1 cohort (n=147), and a computer algorithm for generating CDR scores was developed in this same cohort and re-run in a replication cohort (n=200) to evaluate how well the 60 items retained information from the original 131 items. Short interviews based on the 60 items were then administered to 50 consecutively recruited older individuals, with no symptoms or mild cognitive symptoms, at an Alzheimer's Disease Research Center. Clinical Dementia Rating scores based on short interviews were compared with those from independent long interviews. In the replication cohort, agreement between short and long CDR interviews ranged from κ=0.65 to 0.79, with κ=0.76 for Memory, κ=0.77 for global CDR, and intraclass correlation coefficient for CDR Sum-of-Boxes=0.89. In the cross-sectional validation, short interview scores were slightly lower than those from long interviews, but good agreement was observed for global CDR and Memory (κ≥0.70) as well as for CDR Sum-of-Boxes (intraclass correlation coefficient=0.73). The Structured Interview & Scoring Tool-Massachusetts Alzheimer's Disease Research Center is a brief, reliable, and sensitive instrument for obtaining CDR scores in persons with symptoms along the spectrum of mild cognitive change.

  5. Inspection of licensee - Maintenance programme and activities

    International Nuclear Information System (INIS)

    2013-01-01

    An effective maintenance programme is critical to sustained safe and reliable operation of nuclear power plants. The Working Group on Inspection Practices (WGIP) concluded that when a licensee has an effective maintenance programme, the overall operating safety of the plant is improved and the protection of public health and safety enhanced. All Regulatory Bodies (RB) consider maintenance to be an important area for oversight. Although a variety of inspection practices are being used; RB are actively monitoring licensee performance. Specifically the following conclusions were reached and commendable practices identified: - Maintenance oversight by regulators appears to be in a stable continuous improvement state. Most regulators are executing inspection oversight based on an existing regulatory framework. - The performance of a licensee's maintenance programme is recognized as important part of maintaining nuclear safety. The result of the maintenance program assessment is included in the overall performance assessment of a license. - Maintenance inspection activities are recognized as an important part of the regulatory oversight process. Inspection activities are based on the safety significance and nature of work being performed by the licensee. - The effectiveness of the maintenance inspection activities is recognized to rely on properly qualified inspectors; who are adequately supported by specialists. Training and qualification of inspectors should be based on how the RB reviews and inspects licensee maintenance programmes. - Reporting requirements are identified to provide information on the licensees maintenance programme, and to help guide inspection activities. - Performance Indicators are recognized as a useful tool for helping focus regulatory activities. Basic PI are identified and tracked by the RB, and use of PI by the licensee is monitored. - Inspections are designed to confirm that the licensee is planning and scheduling maintenance with due

  6. Estimating Maintenance Cost for Web Applications

    Directory of Open Access Journals (Sweden)

    Ion IVAN

    2016-01-01

    Full Text Available The current paper tackles the issue of determining a method for estimating maintenance costs for web applications. The current state of research in the field of web application maintenance is summarized and leading theories and results are highlighted. The cost of web maintenance is determined by the number of man-hours invested in maintenance tasks. Web maintenance tasks are categorized into content maintenance and technical maintenance. Research is centered on analyzing technical maintenance tasks. The research hypothesis is formulated on the assumption that the number of man-hours invested in maintenance tasks can be assessed based on the web application’s user interaction level, complexity and content update effort. Data regarding the costs of maintenance tasks is collected from 24 maintenance projects implemented by a web development company that tackles a wide area of web applications. Homogeneity and diversity of collected data is submitted for debate by presenting a sample of the data and depicting the overall size and comprehensive nature of the entire dataset. A set of metrics dedicated to estimating maintenance costs in web applications is defined based on conclusions formulated by analyzing the collected data and the theories and practices dominating the current state of research. Metrics are validated with regards to the initial research hypothesis. Research hypothesis are validated and conclusions are formulated on the topic of estimating the maintenance cost of web applications. The limits of the research process which represented the basis for the current paper are enunciated. Future research topics are submitted for debate.

  7. Intra-session test-retest reliability of magnitude and structure of center of pressure from the Nintendo Wii Balance Board™ for a visually impaired and normally sighted population.

    Science.gov (United States)

    Jeter, Pamela E; Wang, Jiangxia; Gu, Jialiang; Barry, Michael P; Roach, Crystal; Corson, Marilyn; Yang, Lindsay; Dagnelie, Gislin

    2015-02-01

    Individuals with visual impairment (VI) have irreparable damage to one of the input streams contributing to postural stability. Here, we evaluated the intra-session test-retest reliability of the Wii Balance Board (WBB) for measuring Center of Pressure (COP) magnitude and structure, i.e. approximate entropy (ApEn) in fourteen legally blind participants and 21 participants with corrected-to-normal vision. Participants completed a validated balance protocol which included four sensory conditions: double-leg standing on a firm surface with eyes open (EO-firm); a firm surface with eyes closed (EC-firm); a foam surface with EO (EO-foam); and a foam surface with EC (EC-foam). Participants performed the full balance protocol twice during the session, separated by a period of 15min, to determine the intraclass correlation coefficient (ICC). Absolute reliability was determined by the standard error of measurement (SEM). The minimal difference (MD) was estimated to determine clinical significance for future studies. COP measures were derived from data sent by the WBB to a laptop via Bluetooth. COP scores increased with the difficulty of sensory condition indicating WBB sensitivity (all pbalance impairment among VI persons. Copyright © 2014 Elsevier B.V. All rights reserved.

  8. A comparative study on the reliability criteria determination

    International Nuclear Information System (INIS)

    Jerng, Dong Wook; Ju, Tae Young

    2009-01-01

    There are two methods to determine the reliability criteria for maintenance effectiveness monitoring; using the failure probability, and the importance from PRA. Comparisons of the results from these two methods provides an insight on the relevancy of setting the reliability criteria to improve the maintenance effectiveness. (author)

  9. Safety and reliability. V. 1. Proceedings

    International Nuclear Information System (INIS)

    Soares, C.G.

    1997-01-01

    Proceedings of a 1997 conference on industrial safety and reliability are reported. The first volume looks at risk management, probabilistic safety assessment and management styles in various industrial settings, including nuclear power plants. The second volume addresses safety and reliability in the offshore and transport industries, focusing on the role of staff training and appropriate maintenance routines to effectively reduce accidents and outages. (UK)

  10. Advanced maintenance research programs

    International Nuclear Information System (INIS)

    Marston, T.U.; Gelhaus, F.; Burke, R.

    1985-01-01

    The purpose of this paper is to provide the reader with an idea of the advanced maintenance research program at the Electric Power Research Institute (EPRI). A brief description of the maintenance-related activities is provided as a foundation for the advanced maintenance research projects. The projects can be divided into maintenance planning, preventive maintenance program development and implementation, predictive (or conditional) maintenance, and innovative maintenance techniques. The projects include hardware and software development, human factors considerations, and technology promotion and implementation. The advanced concepts include: the incorporation of artificial intelligence into outage planning; turbine and pump maintenance; rotating equipment monitoring and diagnostics with the aid of expert systems; and the development of mobile robots for nuclear power plant maintenance

  11. 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

  12. 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

  13. Selective maintenance of multi-state systems with structural dependence

    International Nuclear Information System (INIS)

    Dao, Cuong D.; Zuo, Ming J.

    2017-01-01

    This paper studies the selective maintenance problem for multi-state systems with structural dependence. Each component can be in one of multiple working levels and several maintenance actions are possible to a component in a maintenance break. The components structurally form multiple hierarchical levels and dependence groups. A directed graph is used to represent the precedence relations of components in the system. A selective maintenance optimization model is developed to maximize the system reliability in the next mission under time and cost constraints. A backward search algorithm is used to determine the assembly sequence for a selective maintenance scenario. The maintenance model helps maintenance managers in determining the best combination of maintenance activities to maximize the probability of successfully completing the next mission. Examples showing the use of the proposed method are presented. - Highlights: • A selective maintenance model for multi-state systems is proposed considering both economic and structural dependence. • Structural dependence is modeled as precedence relationship when disassembling components for maintenance. • Resources for disassembly and maintenance are evaluated using a backward search algorithm. • Maintenance strategies with and without structural dependence are analyzed. • Ignoring structural dependence may lead to over-estimation of system reliability.

  14. 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.

  15. Low-complexity Behavioral Model for Predictive Maintenance of Railway Turnouts

    DEFF Research Database (Denmark)

    Barkhordari, Pegah; Galeazzi, Roberto; Tejada, Alejandro de Miguel

    2017-01-01

    Maintenance of railway infrastructures represents a major cost driver for any infrastructure manager since reliability and dependability must be guaranteed at all times. Implementation of predictive maintenance policies relies on the availability of condition monitoring systems able to assess...

  16. Optimization of maintenance periodicity of complex of NPP safety systems

    International Nuclear Information System (INIS)

    Kolykhanov, V.; Skalozubov, V.; Kovrigkin, Y.

    2006-01-01

    The analysis of the positive and negative aspects connected to maintenance of the safety systems equipment which basically is in a standby state is executed. Tests of systems provide elimination of the latent failures and raise their reliability. Poor quality of carrying out the tests can be a source of the subsequent failures. Therefore excess frequency of tests can result in reducing reliability of safety systems. The method of optimization of maintenance periodicity of the equipment taking into account factors of its reliability and restoration procedures quality is submitted. The unavailability factor is used as a criterion of optimization of maintenance periodicity. It is offered to use parameters of reliability of the equipment and each of safety systems of NPPs received at developing PSA. And it is offered to carry out the concordance of maintenance periodicity of systems within the NPP maintenance program taking into account a significance factor of the system received on the basis of the contribution of system in CDF. Basing on the submitted method the small computer code is developed. This code allows to calculate reliability factors of a separate safety system and to determine optimum maintenance periodicity of its equipment. Optimization of maintenance periodicity of a complex of safety systems is stipulated also. As an example results of optimization of maintenance periodicity at Zaporizhzhya NPP are presented. (author)

  17. Maintenance cost models in deregulated power systems under opportunity costs

    International Nuclear Information System (INIS)

    Al-Arfaj, K.; Dahal, K.; Azaiez, M.N.

    2007-01-01

    In a centralized power system, the operator is responsible for scheduling maintenance. There are different types of maintenance, including corrective maintenance; predictive maintenance; preventive maintenance; and reliability-centred maintenance. The main cause of power failures is poor maintenance. As such, maintenance costs play a significant role in deregulated power systems. They include direct costs associated with material and labor costs as well as indirect costs associated with spare parts inventory, shipment, test equipment, indirect labor, opportunity costs and cost of failure. In maintenance scheduling and planning, the cost function is the only component of the objective function. This paper presented the results of a study in which different components of maintenance costs were modeled. The maintenance models were formulated as an optimization problem with single and multiple objectives and a set of constraints. The maintenance costs models could be used to schedule the maintenance activities of power generators more accurately and to identify the best maintenance strategies over a period of time as they consider failure and opportunity costs in a deregulated environment. 32 refs., 4 tabs., 4 figs

  18. Regulatory oversight of maintenance activities at nuclear power plants in France

    International Nuclear Information System (INIS)

    Bouton, J.P.; Lallement, J.

    1997-01-01

    In France the nuclear safety authority sets out the main safety objectives but the operator remains the first responsible for the NPP safety. During the operation, operators have to demonstrate that the safety level remains the same as defined in the design studies. Maintenance contributes to meet this objective. The French regulation insists on the quality of the safety related components maintenance, especially in the 1984 order. All gap between results and requirements have to be analyzed by operator who provide feedback measures to avoid similar failure to occur. This gap have to be mentioned to regulators. The use of probabilistic safety analysis (PSA) and reliability centered maintenance (RCM) methods is not well developed in France to optimize maintenance. For the French regulatory, the major difficulties in the use of PSA are: The impossibility to detect unanticipated failure mode; the validity of the input data; the validity of model use, based on ''engineering judgement''. For the specific case of passive components inspection, such as the vessel of the primary circuit, the French regulator has already indicated to the operator that the optimization of maintenance by use of PSA cannot be used, for the following reasons: The safety analysis does not take into account the failure of the vessel; unanticipated failure modes have already damaged part of the primary circuit; the use of defense in depth concept requires a systematic detection of any defect on the vessel. (author)

  19. Development of optical fiber cable's inspection technology and maintenance criteria

    International Nuclear Information System (INIS)

    Kim, Min-Su; Ju, Hee-Wan; Shim, Seon-Heum; Lee, Youn-Ki; Kim, Jin-Il; Huh, Tae-Young

    2008-01-01

    Improve the reliability and establish the systematic maintenance methods for the digital control facilities' optical fiber cable, reviewed the technical requirements and the current maintenance procedures, analyzed the optical fiber cable's characteristics through actual test like bending, tension, attenuation. Based on the results of review, test and analysis, prepared the maintenance criteria and standard maintenance guideline. Also we verified those can be applied directly to the operating nuclear power plant through the actual test at Ulchin Unit 6. The details of test and analysis are presented in this paper. Also introduce the contents of maintenance criteria and guidelines

  20. Integration of infrared thermography into various maintenance methodologies

    Science.gov (United States)

    Morgan, William T.

    1993-04-01

    Maintenance methodologies are in developmental stages throughout the world as global competitiveness drives all industries to improve operational efficiencies. Rapid progress in technical advancements has added an additional strain on maintenance organizations to progressively change. Accompanying needs for advanced training and documentation is the demand for utilization of various analytical instruments and quantitative methods. Infrared thermography is one of the primary elements of engineered approaches to maintenance. Current maintenance methodologies can be divided into six categories; Routine ('Breakdown'), Preventive, Predictive, Proactive, Reliability-Based, and Total Productive (TPM) maintenance. Each of these methodologies have distinctive approaches to achieving improved operational efficiencies. Popular though is that infrared thermography is a Predictive maintenance tool. While this is true, it is also true that it can be effectively integrated into each of the maintenance methodologies for achieving desired results. The six maintenance strategies will be defined. Infrared applications integrated into each will be composed in tabular form.

  1. Evaluations of maintenance effectiveness on unavailability and risk

    International Nuclear Information System (INIS)

    Vesely, W.E.

    1993-01-01

    A methodology is presented for quantifying the effectiveness of maintenance on unavailability and on risk. The methodology is based on standard Markov modeling principles. What is new is the application to quantify maintenance effectiveness by explicitly quantifying maintenance benefits as well as maintenance's negative contributions. Maintenance effects are quantified by defining a degraded state for the component in addition to an operational state and a failed state which are usually defined. The maintenance model which is developed is a natural extension of the standard models used in reliability analysis and in Probabilistic Risk Assessments (PRAs). The results which are obtained can be directly used in PRAs. Applications of the methodology are presented by quantifying maintenance effectiveness on component performance and component unavailability for specific maintenance schedules

  2. Problematics of Reliability of Road Rollers

    Science.gov (United States)

    Stawowiak, Michał; Kuczaj, Mariusz

    2018-06-01

    This article refers to the reliability of road rollers used in a selected roadworks company. Information on the method of road rollers service and how the service affects the reliability of these rollers is presented. Attention was paid to the process of the implemented maintenance plan with regard to the machine's operational time. The reliability of road rollers was analyzed by determining and interpreting readiness coefficients.

  3. Unsurfaced Road Maintenance Management

    Science.gov (United States)

    1992-12-01

    This draft manual describes an unsurfaced road maintenance management system for use on military installations. This system is available in either a manual or computerized mode (Micro PAVER). The maintenance standards prescribed should protect Govern...

  4. Winter maintenance performance measure.

    Science.gov (United States)

    2016-01-01

    The Winter Performance Index is a method of quantifying winter storm events and the DOTs response to them. : It is a valuable tool for evaluating the States maintenance practices, performing post-storm analysis, training : maintenance personnel...

  5. Competence within Maintenance

    OpenAIRE

    Nerland, Annette Smørholm

    2010-01-01

    Maintenance can be a contributing factor to unwanted events, as well as desired events and states. Human competence can be defined as the ability to perform a specific task, action or function successfully, and is therefore a key factor to proper execution of maintenance tasks. Hence,maintenance will have negative consequences if done wrong, and give positive results when done right. The purpose of this report is to study the many aspects of maintenance competence. Endeavoring to improve ...

  6. Asphalt in Pavement Maintenance.

    Science.gov (United States)

    Asphalt Inst., College Park, MD.

    Maintenance methods that can be used equally well in all regions of the country have been developed for the use of asphalt in pavement maintenance. Specific information covering methods, equipment and terminology that applies to the use of asphalt in the maintenance of all types of pavement structures, including shoulders, is provided. In many…

  7. Optimization of surface maintenance

    International Nuclear Information System (INIS)

    Oeverland, E.

    1990-01-01

    The present conference paper deals with methods of optimizing the surface maintenance of steel-made offshore installations. The paper aims at identifying important approaches to the problems regarding the long-range planning of an economical and cost effective maintenance program. The methods of optimization are based on the obtained experiences from the maintenance of installations on the Norwegian continental shelf. 3 figs

  8. Hardware and software maintenance strategies for upgrading vintage computers

    International Nuclear Information System (INIS)

    Wang, B.C.; Buijs, W.J.; Banting, R.D.

    1992-01-01

    The paper focuses on the maintenance of the computer hardware and software for digital control computers (DCC). Specific design and problems related to various maintenance strategies are reviewed. A foundation was required for a reliable computer maintenance and upgrading program to provide operation of the DCC with high availability and reliability for 40 years. This involved a carefully planned and executed maintenance and upgrading program, involving complementary hardware and software strategies. The computer system was designed on a modular basis, with large sections easily replaceable, to facilitate maintenance and improve availability of the system. Advances in computer hardware have made it possible to replace DCC peripheral devices with reliable, inexpensive, and widely available components from PC-based systems (PC = personal computer). By providing a high speed link from the DCC to a PC, it is now possible to use many commercial software packages to process data from the plant. 1 fig

  9. NIF Maintenance Plan March 2011

    Energy Technology Data Exchange (ETDEWEB)

    Van Wonterghem, Bruno M. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2014-01-30

    Ensuring the reliability of the NIF, including its support systems and utilities, is essential to ensuring the availability of the NIF in its support of laser operations. This document identifies the policies and procedures necessary to perform and support the maintenance of the NIF’s systems. These systems are all encompassing and include the facility, beampath, Line Replaceable Units (LRUs), Safety Interlock System (SIS), and diagnostics and utilities that create the environments within the beampath consisting of vacuum, argon, or clean dry air.

  10. Equipment Reliability Program in NPP Krsko

    International Nuclear Information System (INIS)

    Skaler, F.; Djetelic, N.

    2006-01-01

    Operation that is safe, reliable, effective and acceptable to public is the common message in a mission statement of commercial nuclear power plants (NPPs). To fulfill these goals, nuclear industry, among other areas, has to focus on: 1 Human Performance (HU) and 2 Equipment Reliability (EQ). The performance objective of HU is as follows: The behaviors of all personnel result in safe and reliable station operation. While unwanted human behaviors in operations mostly result directly in the event, the behavior flaws either in the area of maintenance or engineering usually cause decreased equipment reliability. Unsatisfied Human performance leads even the best designed power plants into significant operating events, which can be found as well-known examples in nuclear industry. Equipment reliability is today recognized as the key to success. While the human performance at most NPPs has been improving since the start of WANO / INPO / IAEA evaluations, the open energy market has forced the nuclear plants to reduce production costs and operate more reliably and effectively. The balance between these two (opposite) goals has made equipment reliability even more important for safe, reliable and efficient production. Insisting on on-line operation by ignoring some principles of safety could nowadays in a well-developed safety culture and human performance environment exceed the cost of electricity losses. In last decade the leading USA nuclear companies put a lot of effort to improve equipment reliability primarily based on INPO Equipment Reliability Program AP-913 at their NPP stations. The Equipment Reliability Program is the key program not only for safe and reliable operation, but also for the Life Cycle Management and Aging Management on the way to the nuclear power plant life extension. The purpose of Equipment Reliability process is to identify, organize, integrate and coordinate equipment reliability activities (preventive and predictive maintenance, maintenance

  11. Design of an operator support system for online maintenance at nuclear power plant

    International Nuclear Information System (INIS)

    Chu Yongyue; Li Huwei; Gao Qiang; Yi Yan; Yang Ming

    2013-01-01

    Online maintenance based on reliability centered management is pivotal for the safe and economical operation of Nuclear Power Plant (NPP). This paper presents an operator support system through which the operators can effectively manage plant configuration and identify the weaknesses in plant operation. The proposed operator support system is based on the GO-FLOW, which is a success-oriented availability analysis methodology and can be used for evaluating phased missions. In this paper, the design of the proposed operator support system is introduced through a case study of the Auxiliary Feed Water System (AFWS). (author)

  12. Maintenance and Outage Management Assessment (MOMA)

    International Nuclear Information System (INIS)

    2005-01-01

    The competitive environment has significant implications for nuclear power plant (NPP) operations, which include, inter alia, the need for efficient use of resources and effective management of plant activities of maintenance and outages. The purpose of NPP maintenance and outages is to allow NPPs to use all those functions necessary for safe and reliable power production by keeping them available and adequate maintenance programme is essential. The maintenance programme covers all preventive and remedial measures, both administrative and technical, necessary to identify and mitigate degradation of a functioning system, structure or component, or restore the design functions of a failed system, structure or component to an acceptable level. In response to the needs of MSs, NPES (Nuclear Power Section, Division of Nuclear Power, IAEA) plans to strengthen its services. NPES services will not only continue to provide its 'traditional' products of publications of nuclear industrial best practices and technical implementation of TC projects on plant maintenance and outage management, but also be expanded to deliver, in a timely manner, technical support missions as requested by MSs for NPPs. One of many services is Maintenance and Outage Management Assessment (MOMA). The NPP can obtain support and assistance in assessment and optimisation of its maintenance program and/or outage management. It aims to help the NPP improve its performance of maintenance and outage in a competitive nuclear power business environment. The specific benefits of the assessment are as follows: a) disseminate nuclear industrial best practices on maintenance program and outage management in the world, b) benchmark, evaluate and optimise the approach of maintenance program and outage management and c) identify solutions to known problems at nuclear power plants, if any. MOMA is conducted at the request of NPPs of any IAEA Member States. MOMA consists in a technical mission/visit for 1-3 weeks by

  13. 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

  14. Smallest detectable change and test-retest reliability of a self-reported outcome measure: Results of the Center for Epidemiologic Studies Depression Scale, General Self-Efficacy Scale, and 12-item General Health Questionnaire.

    Science.gov (United States)

    Ohno, Shotaro; Takahashi, Kana; Inoue, Aimi; Takada, Koki; Ishihara, Yoshiaki; Tanigawa, Masaru; Hirao, Kazuki

    2017-12-01

    This study aims to examine the smallest detectable change (SDC) and test-retest reliability of the Center for Epidemiologic Studies Depression Scale (CES-D), General Self-Efficacy Scale (GSES), and 12-item General Health Questionnaire (GHQ-12). We tested 154 young adults at baseline and 2 weeks later. We calculated the intra-class correlation coefficients (ICCs) for test-retest reliability with a two-way random effects model for agreement. We then calculated the standard error of measurement (SEM) for agreement using the ICC formula. The SEM for agreement was used to calculate SDC values at the individual level (SDC ind ) and group level (SDC group ). The study participants included 137 young adults. The ICCs for all self-reported outcome measurement scales exceeded 0.70. The SEM of CES-D was 3.64, leading to an SDC ind of 10.10 points and SDC group of 0.86 points. The SEM of GSES was 1.56, leading to an SDC ind of 4.33 points and SDC group of 0.37 points. The SEM of GHQ-12 with bimodal scoring was 1.47, leading to an SDC ind of 4.06 points and SDC group of 0.35 points. The SEM of GHQ-12 with Likert scoring was 2.44, leading to an SDC ind of 6.76 points and SDC group of 0.58 points. To confirm that the change was not a result of measurement error, a score of self-reported outcome measurement scales would need to change by an amount greater than these SDC values. This has important implications for clinicians and epidemiologists when assessing outcomes. © 2017 John Wiley & Sons, Ltd.

  15. 76 FR 23801 - North American Electric Reliability Corporation; Order Approving Reliability Standard

    Science.gov (United States)

    2011-04-28

    ... have an operating plan and facilities for backup functionality to ensure Bulk-Power System reliability... entity's primary control center on the reliability of the Bulk-Power System. \\1\\ Mandatory Reliability... potential impact of a violation of the Requirement on the reliability of the Bulk-Power System. The...

  16. EPR design for maintenance

    International Nuclear Information System (INIS)

    Krugmann, U.

    1998-01-01

    Preventive maintenance is very important in achieving high plant availability. For the European Pressurized Reactor (EPR) preventive maintenance has been carefully addressed in the design stage. This is particularly necessary because of the traditionally different maintenance strategies employed in France and Germany. This paper emphasizes the following features introduced in the ERP design to minimize the duration of the refueling outage: (1) containment accessibility during power operation; (2) overall plant layout to facilitate inspections and maintenances within the containment; and (3) safety system design for enabling preventive maintenance during power operation. (author)

  17. Managing nuclear maintenance

    International Nuclear Information System (INIS)

    Anon.

    1990-01-01

    For utilities operating nuclear powerplants, the rules of the game continue to change. Conflicting regulatory pressures and a tougher competitive environment will make management's job more complicated and difficult in the 1990s. Dealing with these pressures successfully requires greater attention to maintenance effectiveness. Utilities can help shape their future environment by developing a well-planned strategy to guide their actions. Parts of the strategy that are discussed include developing a sound maintenance philosophy, selecting a service company, radiation exposure, and managing spare parts. This article also addresses the Swedish experience in maintenance, German philosophy regarding maintenance and the current maintenance practices of the Electricite de France

  18. AIRCRAFT MAINTENANCE HANGAR

    Directory of Open Access Journals (Sweden)

    GEAMBASU Gabriel George

    2017-05-01

    Full Text Available The paper presents the maintenance process that is done on an airplane, at a certain period of time, or after a number of flight hours or cycles and describes the checks performed behind each inspection. The first part of research describes the aircraft maintenance process that has to be done after an updated maintenance manual according with aircraft type, followed by a short introduction about maintenance hangar. The second part of the paper presents a hangar design with a foldable roof and walls, which can be folded or extended, over an airplane when a maintenance process is done, or depending on weather condition.

  19. Bulk Fuel Storage Requirements for Maintenance, Repair, and Environmental Projects at Fort Hood, Texas

    National Research Council Canada - National Science Library

    Carros, Deborah

    2000-01-01

    This report is one in a series that addresses the accuracy and reliability of maintenance, repair, environmental, and construction requirements for bulk fuel storage and delivery systems infrastructure...

  20. The ATOMKI Accelerator Center

    International Nuclear Information System (INIS)

    Biri, S.; Kormany, Z.; Berzi, I.; Hunyadi, M.

    2009-01-01

    In 2009 a new division was established in our institute: the ATOMKI Accelerator Center (AAC). Before this time the facilities and staff of AAC belonged to other departments of the institute. The re-organization however, was necessary. It was understood that the translocation of all the accelerators into a centralized unit is advantageous in numerous fields. Here we just mention some of them. The submission of any instrumentation type proposal (EU or domestic) will be easier and has a higher chance to be supported. The organization and distribution of the beamtimes will be more equal and optimal. The usage of the maintenance and spare tools can became better and cheaper. The operating staff (cca. 20 person) can serve at more than one accelerator and the teams can help each other. The accelerator center actually became a fourth new basic unit of the institute besides the three traditional scientific divisions (see the Atomki homepage for the organization chart). The following six main facilities belong to the accelerator center: Cyclotron; VdG-5 accelerator; VdG-1 accelerator; ECR ion source; Isotope separator; Tandetron (under installation). In figure 1 the placements of these machines are shown in an artistic 3D map of the Atomki. The table 1 summarizes the main parameters of the accelerators. More detailed technical specification of the machines can be found in the new homepage of the center. In 2009 all the accelerators operated as scheduled, safely and without major breakdowns. After the experiences in the first months it can be concluded that the new center works well both for technical and human point of views. In the next sub-chapters the 2009 operation and development details of the individual accelerators are summarized. Cyclotron operation. The operation of the cyclotron in 2009 was concentrated to the usual 9 months; January, July and August were reserved for maintenance and holidays. The overall working time of the accelerator was 2009 hours; the time

  1. Maintenance management systems

    International Nuclear Information System (INIS)

    Rohan, M. de

    1989-01-01

    This paper is concerned principally with Maintenance Management systems and their effective introduction into organisations. Maintenance improvement is basically a problem of managing the maintenance department in the broadest sense. Improvement does not only lie in the area of special techniques, systems or procedures; although they are valuable tools, but rather in a balanced attack, carefully guided by management. Over recent years, maintenance systems have received the major emphasis and in many instances the selection of the system has become a pre-occupation, whereas the importance of each maintenance function must be recognised and good management practices applied to all maintenance activities. The ingredients for success in the implementation of maintenance management systems are summarised as: having a management committee, clear objectives, project approach using project management techniques and an enthusiastic leader, user managed and data processing supported project, realistic budget and an understanding of the financial audit requirements. (author)

  2. Lean Maintenance Applied to Improve Maintenance Efficiency in Thermoelectric Power Plants

    Directory of Open Access Journals (Sweden)

    Orlando Duran

    2017-10-01

    Full Text Available Thermoelectric power plants consist of a set of critical equipment that require high levels of availability and reliability. Due to this, maintenance of these physical assets is gaining momentum in industry. Maintenance is considered as an activity that contributes to improving the availability, efficiency and productivity of each piece of equipment. Several techniques have been used to achieve greater efficiencies in maintenance, among which we can find the lean maintenance philosophy. Despite the wide diffusion of lean maintenance, there is no structured method that supports the prescription of lean tools applied to the maintenance function. This paper presents the experience gathered in two lean maintenance projects in thermoelectric power plants. The application of lean techniques was based on using a previously developed multicriterial decision making process that uses the Fuzzy Analytic Hierarchy Process (AHP methodology to carry out a diagnosis and prescription tasks. That methodology allowed the prescription of the appropriated lean techniques to resolve the main deficiencies in maintenance function. The results of applying such lean tools show that important results can be obtained, making the maintenance function in thermoelectric power plants more efficient and lean.

  3. Maintenance policy of the nuclear park

    International Nuclear Information System (INIS)

    Teisset, J.M.

    1995-01-01

    The nuclear installations maintenance policy of Electricite de France (EDF) follows three axes: first, controlling the aging of the production tool to warrant the safety and the functional reliability during the 40 years of installations service life. Second: optimizing the maintenance activities taking into account the safety goals, costs, security, dosimetry, duration of outages, and intervention conditions in the decisions. Third: developing a real partnership with contractors. EDF has decided to decentralize its maintenance operations towards each unit which is in charge of the organization of its own project. A better management of the contractor personnel has allowed to increase the performances of maintenance operations. The development of long-term agreements with contractors has permitted to reinforce the qualification, the responsibility and the efficiency of the personnel and to improve their means and tools. (J.S.). 1 photo

  4. South Blackwater Coal`s maintenance program

    Energy Technology Data Exchange (ETDEWEB)

    Nash, J. [South Blackwater Coal Limited, Blackwater, Qld. (Australia)

    1998-09-01

    The South Blackwater operation consists of two opencut mining areas and two underground mines (Laleham and Kenmure) near Blackwater in central Queensland, all of which supply coal to a central coal preparation plant. South Blackwater Coal Ltd. recently developed a maintenance improvement programme, described in this article. The programme involved implementation systems of key performance indicators (KPIs), benchmaking, condition monitoring, work planning and control, failure analysis and maintenance audit. Some improvements became almost immediately apparent, others were quite gradual. Major results included: improved availability (and reliability) of all opencast fleets, improvements in rear dump availability; reduced maintenance man-hours for opencast fleets; and increased availability of the coal handling and preparation plant. The paper is an edited version of that presented at the `Maintenance in mining conference` 16-19 March 1998, held in Bali, Indonesia. 4 figs., 2 photos.

  5. RELIABILITY OF LENTICULAR EXPANSION COMPENSATORS

    Directory of Open Access Journals (Sweden)

    Gabriel BURLACU,

    2011-11-01

    Full Text Available Axial lenticular compensators are made to take over the longitudinal heat expansion, shock , vibration and noise, made elastic connections for piping systems. In order to have a long life for installations it is necessary that all elements, including lenticular compensators, have a good reliability. This desire can be did by technology of manufactoring and assembly of compensators, the material for lenses and by maintenance.of compensator

  6. 7 CFR 1767.27 - Operation and maintenance expenses.

    Science.gov (United States)

    2010-01-01

    ..., DEPARTMENT OF AGRICULTURE (CONTINUED) ACCOUNTING REQUIREMENTS FOR RUS ELECTRIC BORROWERS Uniform System of... Waterways 544Maintenance of Electric Plant 545Maintenance of Miscellaneous Hydraulic Plant Other Power....1Load Dispatch-Reliability 561.2Load Dispatch-Monitor and Operate Transmission System 561.3Load Dispatch...

  7. Maintenance facilities, stores and records

    International Nuclear Information System (INIS)

    Fischer, K.

    1986-01-01

    The topics of this report are: on-site or off-site facilities. On-site facilities: workshops and special facilities. KWU's Service Center, a typical off-site supporting facility in Germany, capabilities and activities. A pool for special tools and equipment: devices for plugging of nozzles, for handling of RPU-studs and RPU internals etc. Devices for and management of radiological protection on-site for typical outage work. Spare parts and spare part management on site, typical examples. KWU's centralized spare part pools for components, generators and turbines etc. A computerized system for spare parts storage and maintenance planning. A system for mutual exchange of operational experience with respect to maintenance and repair activities. Systematic evaluation of failures and statistical results. (orig./GL)

  8. FFTF Work Control Center

    International Nuclear Information System (INIS)

    Talbot, M.D.

    1986-01-01

    A centralized Work Control Center (WCC) is responsible for assuring that maintenance and modification of the Fast Flux Test Facility (FFTF) is performed in accordance with written procedures that ensure design integrity, personnel and public safety, and equipment and system availability for the computerized Master Information Data Acquisition System (MIDAS). Each maintenance task is logged into MIDAS from a Work Request from that has been reviewed and prioritized by the WCC. Thereafter, MIDAS is used to track schedule, manpower and material requirements; authorize field work; and close out the maintenance activity

  9. Implementation of maintenance rule for structures

    International Nuclear Information System (INIS)

    Ashar, H.; Bagchi, G.

    1999-01-01

    The maintenance rule, 10 CFR 50.65, 'Requirements for Monitoring the Effectiveness of Maintenance at Nuclear Power Plants', was published by the Nuclear Regulatory Commission (NRC) in the Federal Register (56 FR 31324) on July 10, 1991. The rule became effective on July 10, 1996, giving nuclear power plant licensees 5 years to implement it. During 1994-1995, NRC staff visited nine nuclear power plant sites to observe licensees' preparations for implementation of the rule. The teams found that most of the licensees had not established goals, or performance criteria for monitoring structures at their sites. The licensees contended that the structures were inherently reliable and required no monitoring under the maintenance rule. On the basis of earlier site visits performed by NRC staff to assess the condition of structures, the NRC staff could not accept this contention, and clarified its position in Revision 1 of Regulatory Guide 1.160, 'Monitoring the Effectiveness of Maintenance at Nuclear Power Plants'. This paper discusses the applicability of the maintenance rule criteria for structures and its usefulness in ensuring that the structures, systems, and components within the scope of the maintenance rule are capable of fulfilling their intended functions. Also discussed are the aspects of maintenance rule efforts that could be useful for license renewal applications. (orig.)

  10. Capacity and reliability analyses with applications to power quality

    Science.gov (United States)

    Azam, Mohammad; Tu, Fang; Shlapak, Yuri; Kirubarajan, Thiagalingam; Pattipati, Krishna R.; Karanam, Rajaiah

    2001-07-01

    The deregulation of energy markets, the ongoing advances in communication networks, the proliferation of intelligent metering and protective power devices, and the standardization of software/hardware interfaces are creating a dramatic shift in the way facilities acquire and utilize information about their power usage. The currently available power management systems gather a vast amount of information in the form of power usage, voltages, currents, and their time-dependent waveforms from a variety of devices (for example, circuit breakers, transformers, energy and power quality meters, protective relays, programmable logic controllers, motor control centers). What is lacking is an information processing and decision support infrastructure to harness this voluminous information into usable operational and management knowledge to handle the health of their equipment and power quality, minimize downtime and outages, and to optimize operations to improve productivity. This paper considers the problem of evaluating the capacity and reliability analyses of power systems with very high availability requirements (e.g., systems providing energy to data centers and communication networks with desired availability of up to 0.9999999). The real-time capacity and margin analysis helps operators to plan for additional loads and to schedule repair/replacement activities. The reliability analysis, based on computationally efficient sum of disjoint products, enables analysts to decide the optimum levels of redundancy, aids operators in prioritizing the maintenance options for a given budget and monitoring the system for capacity margin. The resulting analytical and software tool is demonstrated on a sample data center.

  11. Maintenance program, organization and procedures

    International Nuclear Information System (INIS)

    Schegk, J.R.R.

    1986-01-01

    The Rheinisch-Westfaelisches Elektrizitaetswerk AG (RWE) operates two pressurized water reactors (PWR) with 1.200 MW and 1.300 MW and two boiling water reactors (BWR) with an electrical output of 1.300 MW each. The PWR were commissioned in 1975 and 1977 respectively and have so far achieved a cumulative availability of 72%. The BWR started operating in 1984 and 1985. Since than they have been generating with a cumulative availability of 88%. The reliability of the nuclear power stations resulted in a trouble-free operation. For the last two years, the unscheduled non-availability amounted to 3,7% and 6,5% for the PWR and the BWR respectively. These favourable operating results derive inter alia from systematic preventive maintenance and consistent outage management. Apart from the personnel structure in the power stations the functional sequence of planning, control, performance as well as evaluation of maintenance results constitute a closed cycle. In order to ensure and support an effective cooperation of the above mentioned four functional sequences of a cycle, uniform and computer-assisted information and planning aids have been introduced such as task lists, job ordering, time scheduling and materials management. As a result of this preventive maintenance system the average refueling outage period is 35 to 42 days. (orig.)

  12. Reliability in automotive and mechanical engineering determination of component and system reliability

    CERN Document Server

    Bertsche, Bernd

    2008-01-01

    In the present contemporary climate of global competition in every branch of engineering and manufacture it has been shown from extensive customer surveys that above every other attribute, reliability stands as the most desired feature in a finished product. To survive this relentless fight for survival any organisation, which neglect the plea of attaining to excellence in reliability, will do so at a serious cost Reliability in Automotive and Mechanical Engineering draws together a wide spectrum of diverse and relevant applications and analyses on reliability engineering. This is distilled into this attractive and well documented volume and practising engineers are challenged with the formidable task of simultaneously improving reliability and reducing the costs and down-time due to maintenance. The volume brings together eleven chapters to highlight the importance of the interrelated reliability and maintenance disciplines. They represent the development trends and progress resulting in making this book ess...

  13. University of Tennessee - Industry collaborative research and development in preventive maintenance technology

    International Nuclear Information System (INIS)

    Upadhyaya, B.R.

    1992-01-01

    The Preventive Maintenance Engineering Laboratory (PMEL) was inaugurated at the University of Tennessee Nuclear Engineering Department in September 1989. The startup funding was provided by Gilbert/Commonwealth, Inc. The purpose of PMEL is to identify maintenance-related problems in the power and process industries and to find their solutions through the development and application of emerging technologies. These include advanced digital signal processing, applied artificial intelligence (AI), artificial neural networks, and reliability based methods. The Laboratory activities are being expanded by the formation of an industrial consortium within the Measurement and Control Engineering Center at the University of Tennessee. Several research and development projects in preventive maintenance are being carried out. These include condition monitoring of air operated valves, automated diagnostics of motor operated valves, instrument calibration, verification, and estimation of expected residual life of electric motors using applied AI technology and reliability-based methods. The new methodology will be applied to other industrial subsystems. A long-term research and development project is being sponsored by the T.V.A. Nuclear Maintenance Department. The overall objective of the research program is to develop and apply advanced artificial intelligence and information processing methods to the problems of plant performance monitoring and preventive maintenance. The program includes the development of a workstation/PC-based, networking of plant information for easy access to operational and management personnel, implementation of a sensor verification system, monitoring of feedwater flow venturi fouling and heat rate balance, and integration of signal validation, command validation, and fault-tolerant control strategies

  14. Different Reliability Assessment Approaches for Wave Energy Converters

    DEFF Research Database (Denmark)

    Ambühl, Simon; Kramer, Morten Mejlhede; Sørensen, John Dalsgaard

    2015-01-01

    Reliability assessments are of importance for wave energy converters (WECs) due to the fact that accessibility might be limited in case of failure and maintenance. These failure rates can be adapted by reliability considerations. There are two different approaches to how reliability can...

  15. Reliability Analysis of Fatigue Fracture of Wind Turbine Drivetrain Components

    DEFF Research Database (Denmark)

    Berzonskis, Arvydas; Sørensen, John Dalsgaard

    2016-01-01

    in the volume of the casted ductile iron main shaft, on the reliability of the component. The probabilistic reliability analysis conducted is based on fracture mechanics models. Additionally, the utilization of the probabilistic reliability for operation and maintenance planning and quality control is discussed....

  16. Analysis of Fleet Readiness Center Southwest Concept Integration: New-Employee Orientation and Communication Processes

    National Research Council Canada - National Science Library

    Clemmons, Francini R; Falconieri, Holly M

    2007-01-01

    Fleet Readiness Center Southwest has embraced integration of personnel and processes from Aircraft Intermediate Maintenance Departments and Naval Aviation Depots supporting Naval Aviation Maintenance...

  17. Software evolution and maintenance

    CERN Document Server

    Tripathy, Priyadarshi

    2014-01-01

    Software Evolution and Maintenance: A Practitioner's Approach is an accessible textbook for students and professionals, which collates the advances in software development and provides the most current models and techniques in maintenance.Explains two maintenance standards: IEEE/EIA 1219 and ISO/IEC14764Discusses several commercial reverse and domain engineering toolkitsSlides for instructors are available onlineInformation is based on the IEEE SWEBOK (Software Engineering Body of Knowledge)

  18. Status of fusion maintenance

    International Nuclear Information System (INIS)

    Fuller, G.M.

    1984-01-01

    Effective maintenance will be an essential ingredient in determining fusion system productivity. This level of productivity will result only after close attention is paid to the entire system as an entity and appropriate integration of the elements is made. The status of fusion maintenance is reviewed in the context of the entire system. While there are many challenging developmental tasks ahead in fusion maintenance, the required technologies are available in several high-technology industries, including nuclear fission

  19. Laboratory equipment maintenance contracts.

    Science.gov (United States)

    Boudreau, D A; Scheer, W D; Catrou, P G

    1985-12-01

    The increasing level of technical sophistication and complexity found in clinical laboratory instrumentation today more than ever demands careful attention to maintenance service needs. The time-worn caution for careful definition of requirements for acquisition of a system should also carry over to acquisition of maintenance service. Guidelines are presented for specifications of terms and conditions for maintenance service from the perspective of the laboratorian in the automated clinical laboratory.

  20. Interactive videodisc in maintenance

    International Nuclear Information System (INIS)

    Zwingelstein, G.; Nguyen Van Nghi, B.

    1986-01-01

    After a recall of the videodisc characteristics, this paper presents its utilization by Electricite de France in the framework of training and maintenance. The SICMA (Interactive Communication System in Maintenance) developed and tested by Electricte de France is presented as also its utilization. It has been tested on the sites of Dampierre and Paluel in the cases of training and maintenance (deconnexion of drive rods of control elements); the conclusions of this experimentation are finally given. 4 refs [fr

  1. Turbine maintenance and modernization

    Energy Technology Data Exchange (ETDEWEB)

    Unga, E. [Teollisuuden Voima Oy, Olkiluoto (Finland)

    1998-12-31

    The disturbance-free operation of the turbine plant plays an important role in reaching good production results. In the turbine maintenance of the Olkiluoto nuclear power plant the lifetime and efficiency of turbine components and the lifetime costs are taken into account in determining the turbine maintenance and modernization/improvement program. The turbine maintenance program and improvement/modernization measures taken in the plant units are described in this presentation. (orig.)

  2. Turbine maintenance and modernization

    Energy Technology Data Exchange (ETDEWEB)

    Unga, E [Teollisuuden Voima Oy, Olkiluoto (Finland)

    1999-12-31

    The disturbance-free operation of the turbine plant plays an important role in reaching good production results. In the turbine maintenance of the Olkiluoto nuclear power plant the lifetime and efficiency of turbine components and the lifetime costs are taken into account in determining the turbine maintenance and modernization/improvement program. The turbine maintenance program and improvement/modernization measures taken in the plant units are described in this presentation. (orig.)

  3. Laboratory simulation of maintenance activity

    International Nuclear Information System (INIS)

    Kantowitz, B.H.

    1988-01-01

    Laboratory research in highly controlled settings can augment, but not replace, studies in plant or training center locations. A laboratory simulation involves abstraction of the human information processing and social interactions required in prototypical maintenance tasks. A variety of independent variables can be studied quickly, efficiently, and at relatively low cost. Sources of human error can be identified in terms of models of human perception, cognition, action, attention, and social/organizational processes. This paper discusses research in progress at the Battelle Human Performance Laboratory. Both theoretical aspects and practical implications are considered. Directions for future human factors research are indicated

  4. Analysis of maintenance strategies

    International Nuclear Information System (INIS)

    Laakso, K.; Simola, K.

    1998-01-01

    The main topics of the presentation include: (1) an analysis model and methods to evaluate maintenance action programs and the support decision to make changes in them and (2) to understand the maintenance strategies in a systems perspective as a basis for future developments. The subproject showed how systematic models for maintenance analysis and decision support, utilising computerised and statistical tool packages, can be taken into use for evaluation and optimisation of maintenance of active systems from the safety and economic point of view

  5. Remote Maintenance Monitoring System -

    Data.gov (United States)

    Department of Transportation — The Remote Maintenance and Monitoring System (RMMS) is a collection of subsystems that includes telecommunication components, hardware, and software, which serve to...

  6. Army Maintenance System Transformation

    National Research Council Canada - National Science Library

    Gilbertson, Frank V

    2006-01-01

    .... Used in conjunction with pertinent historical data and developed with Army transformation goals in mind, General Systems thinking can provide the framework for guiding maintenance transformation...

  7. Human reliability in complex systems: an overview

    International Nuclear Information System (INIS)

    Embrey, D.E.

    1976-07-01

    A detailed analysis is presented of the main conceptual background underlying the areas of human reliability and human error. The concept of error is examined and generalized to that of human reliability, and some of the practical and methodological difficulties of reconciling the different standpoints of the human factors specialist and the engineer discussed. Following a survey of general reviews available on human reliability, quantitative techniques for prediction of human reliability are considered. An in-depth critical analysis of the various quantitative methods is then presented, together with the data bank requirements for human reliability prediction. Reliability considerations in process control and nuclear plant, and also areas of design, maintenance, testing and emergency situations are discussed. The effects of stress on human reliability are analysed and methods of minimizing these effects discussed. Finally, a summary is presented and proposals for further research are set out. (author)

  8. Joint optimization of production scheduling and machine group preventive maintenance

    International Nuclear Information System (INIS)

    Xiao, Lei; Song, Sanling; Chen, Xiaohui; Coit, David W.

    2016-01-01

    Joint optimization models were developed combining group preventive maintenance of a series system and production scheduling. In this paper, we propose a joint optimization model to minimize the total cost including production cost, preventive maintenance cost, minimal repair cost for unexpected failures and tardiness cost. The total cost depends on both the production process and the machine maintenance plan associated with reliability. For the problems addressed in this research, any machine unavailability leads to system downtime. Therefore, it is important to optimize the preventive maintenance of machines because their performance impacts the collective production processing associated with all machines. Too lengthy preventive maintenance intervals may be associated with low scheduled machine maintenance cost, but may incur expensive costs for unplanned failure due to low machine reliability. Alternatively, too frequent preventive maintenance activities may achieve the desired high reliability machines, but unacceptably high scheduled maintenance cost. Additionally, product scheduling plans affect tardiness and maintenance cost. Two results are obtained when solving the problem; the optimal group preventive maintenance interval for machines, and the assignment of each job, including the corresponding start time and completion time. To solve this non-deterministic polynomial-time problem, random keys genetic algorithms are used, and a numerical example is solved to illustrate the proposed model. - Highlights: • Group preventive maintenance (PM) planning and production scheduling are jointed. • Maintenance interval and assignment of jobs are decided by minimizing total cost. • Relationships among system age, PM, job processing time are quantified. • Random keys genetic algorithms (GA) are used to solve the NP-hard problem. • Random keys GA and Particle Swarm Optimization (PSO) are compared.

  9. 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.

  10. Transfer of infrared thermography predictive maintenance technologies to Soviet-designed nuclear power plants: experience at Chernobyl

    Science.gov (United States)

    Pugh, Ray; Huff, Roy

    1999-03-01

    The importance of infrared (IR) technology and analysis in today's world of predictive maintenance and reliability- centered maintenance cannot be understated. The use of infrared is especially important in facilities that are required to maintain a high degree of equipment reliability because of plant or public safety concerns. As with all maintenance tools, particularly those used in predictive maintenance approaches, training plays a key role in their effectiveness and the benefit gained from their use. This paper details an effort to transfer IR technology to Soviet- designed nuclear power plants in Russia, Ukraine, and Lithuania. Delivery of this technology and post-delivery training activities have been completed recently at the Chornobyl nuclear power plant in Ukraine. Many interesting challenges were encountered during this effort. Hardware procurement and delivery of IR technology to a sensitive country were complicated by United States regulations. Freight and shipping infrastructure and host-country customs policies complicated hardware transport. Training activities were complicated by special hardware, software and training material translation needs, limited communication opportunities, and site logistical concerns. These challenges and others encountered while supplying the Chornobyl plant with state-of-the-art IR technology are described in this paper.

  11. Technology Trend in the Maintenance of Nuclear Power Plants

    International Nuclear Information System (INIS)

    Yoon, Kyungsup; Lee, Unjang

    2014-01-01

    In this paper, overall technology evolution is reviewed and the improvements in the plant safety, reliability and productivity are described. And the issue and some recommendation for better maintenance of Korean nuclear power plants are presented as the interim study results on the 'Management and Regulatory Policy for the Nuclear Power Plant Maintenance and Equipment Reliability' under the agreement with the Nuclear Safety and Security Commission. The future trend in the maintenance technologies is also covered. Maintenance is the essential element for the enhancement of plant safety, reliability and economics and also for public safety. Therefore the regulator's involvements and the utility's active participation is inevitable for the better maintenance. For the better sustainability of our nuclear power plants the followings are recommended. ·Establishment of the good maintenance program and continuous improvement. ·Application of OLM on the safety related and non-safety related components by step-by-step approach. ·Improvement PRA technology for the accurate and reliable risk analysis. ·Continuous training and cultivation for the qualified maintenance personnel

  12. Technology Trend in the Maintenance of Nuclear Power Plants

    Energy Technology Data Exchange (ETDEWEB)

    Yoon, Kyungsup; Lee, Unjang [CTO and CEO, Seoul (Korea, Republic of)

    2014-05-15

    In this paper, overall technology evolution is reviewed and the improvements in the plant safety, reliability and productivity are described. And the issue and some recommendation for better maintenance of Korean nuclear power plants are presented as the interim study results on the 'Management and Regulatory Policy for the Nuclear Power Plant Maintenance and Equipment Reliability' under the agreement with the Nuclear Safety and Security Commission. The future trend in the maintenance technologies is also covered. Maintenance is the essential element for the enhancement of plant safety, reliability and economics and also for public safety. Therefore the regulator's involvements and the utility's active participation is inevitable for the better maintenance. For the better sustainability of our nuclear power plants the followings are recommended. ·Establishment of the good maintenance program and continuous improvement. ·Application of OLM on the safety related and non-safety related components by step-by-step approach. ·Improvement PRA technology for the accurate and reliable risk analysis. ·Continuous training and cultivation for the qualified maintenance personnel.

  13. Transfer of technology in maintenance tools

    International Nuclear Information System (INIS)

    Delorme, H.; Cartry, J.P.

    1985-10-01

    For maximum reliability of maintenance operations, FRAMATOME has aimed to improve the accessibility of highly irradiated and contaminated reactor coolant system equipment by the active promotion of an automation and robotization strategy. A number of robot designs have been developed providing replacement of operators inside the steam generator channel head, smooth handling of heavy or cumbersome objects in this zone, easy marking of steam generator tubes and increased speed of repetitive channel head operations: maintenance spider, theta-theta prime robotic service arm, R-theta robotic service arm, remote manipulator arm. Two operations are described: channel head folding cover plate and, operation of the torquing machine for head cover plate

  14. Reliability Characteristics of Power Plants

    Directory of Open Access Journals (Sweden)

    Zbynek Martinek

    2017-01-01

    Full Text Available This paper describes the phenomenon of reliability of power plants. It gives an explanation of the terms connected with this topic as their proper understanding is important for understanding the relations and equations which model the possible real situations. The reliability phenomenon is analysed using both the exponential distribution and the Weibull distribution. The results of our analysis are specific equations giving information about the characteristics of the power plants, the mean time of operations and the probability of failure-free operation. Equations solved for the Weibull distribution respect the failures as well as the actual operating hours. Thanks to our results, we are able to create a model of dynamic reliability for prediction of future states. It can be useful for improving the current situation of the unit as well as for creating the optimal plan of maintenance and thus have an impact on the overall economics of the operation of these power plants.

  15. Benefits of a systematic approach to maintenance for safety and safety related systems

    International Nuclear Information System (INIS)

    Dam, R.F.; Ayazzudin, S.; Nickerson, J.H.

    2003-01-01

    For safety and safety-related 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 results in system unavailability 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. In such cases, the value of the application of a Systematic Assessment of Maintenance (SAM) process, such as Reliability Centered Maintenance (RCM), is questioned. The special case of Standby-Safety systems was discussed in a previous paper, where it was demonstrated how SAM techniques provide useful insight into current system performance, the impact of testing on component and system reliability, and how PSA considerations can be integrated into a comprehensive Maintenance, Surveillance, and Inspection (MSI) strategy. Although the system reliability requirements are an important part of the strategy evaluation, SAM techniques provide a systematic assessment within a broader context. 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 known component degradation mechanisms. This thinking can be extended to safety and safety related systems in general. Over the past 6 years, AECL has been working with CANDU utilities in the development and implementation of a comprehensive and integrated Plant Life Management (PLiM) program. As part of developing a comprehensive plant asset management approach, SAM techniques are used to develop a technical basis that not only works towards ensuring reliable operation of plant systems, but also facilitates the optimization and

  16. Nuclear power plant reliability database management

    International Nuclear Information System (INIS)

    Meslin, Th.; Aufort, P.

    1996-04-01

    In the framework of the development of a probabilistic safety project on site (notion of living PSA), Saint Laurent des Eaux NPP implements a specific EDF reliability database. The main goals of this project at Saint Laurent des Eaux are: to expand risk analysis and to constitute an effective local basis of thinking about operating safety by requiring the participation of all departments of a power plant: analysis of all potential operating transients, unavailability consequences... that means to go further than a simple culture of applying operating rules; to involve nuclear power plant operators in experience feedback and its analysis, especially by following up behaviour of components and of safety functions; to allow plant safety managers to outline their decisions facing safety authorities for notwithstanding, preventive maintenance programme, operating incident evaluation. To hit these goals requires feedback data, tools, techniques and development of skills. The first step is to obtain specific reliability data on the site. Raw data come from plant maintenance management system which processes all maintenance activities and keeps in memory all the records of component failures and maintenance activities. Plant specific reliability data are estimated with a Bayesian model which combines these validated raw data with corporate generic data. This approach allow to provide reliability data for main components modelled in PSA, to check the consistency of the maintenance program (RCM), to verify hypothesis made at the design about component reliability. A number of studies, related to components reliability as well as decision making process of specific incident risk evaluation have been carried out. This paper provides also an overview of the process management set up on site from raw database to specific reliability database in compliance with established corporate objectives. (authors). 4 figs

  17. Nuclear power plant reliability database management

    Energy Technology Data Exchange (ETDEWEB)

    Meslin, Th [Electricite de France (EDF), 41 - Saint-Laurent-des-Eaux (France); Aufort, P

    1996-04-01

    In the framework of the development of a probabilistic safety project on site (notion of living PSA), Saint Laurent des Eaux NPP implements a specific EDF reliability database. The main goals of this project at Saint Laurent des Eaux are: to expand risk analysis and to constitute an effective local basis of thinking about operating safety by requiring the participation of all departments of a power plant: analysis of all potential operating transients, unavailability consequences... that means to go further than a simple culture of applying operating rules; to involve nuclear power plant operators in experience feedback and its analysis, especially by following up behaviour of components and of safety functions; to allow plant safety managers to outline their decisions facing safety authorities for notwithstanding, preventive maintenance programme, operating incident evaluation. To hit these goals requires feedback data, tools, techniques and development of skills. The first step is to obtain specific reliability data on the site. Raw data come from plant maintenance management system which processes all maintenance activities and keeps in memory all the records of component failures and maintenance activities. Plant specific reliability data are estimated with a Bayesian model which combines these validated raw data with corporate generic data. This approach allow to provide reliability data for main components modelled in PSA, to check the consistency of the maintenance program (RCM), to verify hypothesis made at the design about component reliability. A number of studies, related to components reliability as well as decision making process of specific incident risk evaluation have been carried out. This paper provides also an overview of the process management set up on site from raw database to specific reliability database in compliance with established corporate objectives. (authors). 4 figs.

  18. How safe is defect specific maintenance of steam generator tubes?

    International Nuclear Information System (INIS)

    Dvorsek, T.; Cizelj, L.

    1995-01-01

    Outside diameter stress corrosion cracking at the tube to tube support plate intersections is assessed in the paper. The impact of defect specific maintenance on steam generator operation safety and reliability was investigated. This was performed by comparing efficiencies of defect specific and traditional maintenance strategy. The efficiency was studied through expected primary-to-secondary leak rate and tube rupture probability in a case of postulated accidental operating conditions, and number of tubes which shall be plugged using both maintenance strategies. In general, the efficiency of specific maintenance is function of particular steam generator and operating cycle. (author)

  19. Discounted cost model for condition-based maintenance optimization

    International Nuclear Information System (INIS)

    Weide, J.A.M. van der; Pandey, M.D.; Noortwijk, J.M. van

    2010-01-01

    This paper presents methods to evaluate the reliability and optimize the maintenance of engineering systems that are damaged by shocks or transients arriving randomly in time and overall degradation is modeled as a cumulative stochastic point process. The paper presents a conceptually clear and comprehensive derivation of formulas for computing the discounted cost associated with a maintenance policy combining both condition-based and age-based criteria for preventive maintenance. The proposed discounted cost model provides a more realistic basis for optimizing the maintenance policies than those based on the asymptotic, non-discounted cost rate criterion.

  20. Predictive Maintenance (PdM) Centralization for Significant Energy Savings

    Energy Technology Data Exchange (ETDEWEB)

    Smith, Dale

    2010-09-15

    Cost effective predictive maintenance (PdM) technologies and basic energy calculations can mine energy savings form processes or maintenance activities. Centralizing and packaging this information correctly empowers facility maintenance and reliability professionals to build financial justification and support for strategies and personnel to weather global economic downturns and competition. Attendees will learn how to: Systematically build a 'pilot project' for applying PdM and tracking systems; Break down a typical electrical bill to calculate energy savings; Use return on investment (ROI) calculations to identify the best and highest value options, strategies and tips for substantiating your energy reduction maintenance strategies.