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Sample records for based maintenance ganhos

  1. Earnings with Condition Based Maintenance; Ganhos com manutencao preditiva baseada em dados de processo em tempo real

    Energy Technology Data Exchange (ETDEWEB)

    Barabas, Elizabeth [Softbrasil Automacao, Sao Paulo, SP (Brazil)

    2008-07-01

    Keeping active in perfect functioning is essential for any company. Today, the maintenance has been performed in most of the stops for maintenance. In a modern industrial environment, where the systems provide data and process information in real time, it is possible bring the performance of the plant to a optimized level, through the maintenance based on condition of equipment. This work described the earnings with CBM (Condition Based Maintenance)

  2. 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.)

  3. Condition based maintenance in the context of opportunistic maintenance

    NARCIS (Netherlands)

    Koochaki, Javid; Bokhorst, Jos A. C.; Wortmann, Hans; Klingenberg, Warse

    2012-01-01

    Condition based maintenance (CBM) uses the operating condition of a component to predict a failure event. Compared to age based replacement (ABR), CBM usually results in higher availability and lower maintenance costs, since it tries to prevent unplanned downtime and avoid unnecessary preventive

  4. 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

  5. Advantages of condition-based maintenance approach

    International Nuclear Information System (INIS)

    Bareiss, J.; Roos, E.; Jovanovic, A.; Perunicic, M.; Balos, D.

    2004-01-01

    Pilot applications in EnBW steam boiler components and high-pressure pipe systems in the context of the European research project RIMAP (''Risk Based Inspection and Maintenance Procedures for European Industry'') showed that application of a risk-based maintenance strategy (e.g. RIMAP) will make the decision process more transparent and enable better condition-oriented maintenance. With regard to life management of the systems (availability, product quality), this appears to be more important than than the aspect of cost reduction in the maintenance sector, although the latter may not be unwelcome. (orig.) [de

  6. Maintenance evaluation using risk based criteria

    International Nuclear Information System (INIS)

    Torres Valle, A.

    1996-01-01

    The maintenance evaluation is currently performed by using economic and, in some case, technical equipment failure criteria, however this is done to a specific equipment level. In general, when statistics are used the analysis for maintenance optimization are made isolated and whit a post mortem character; The integration provided by mean of Probabilistic Safety assessment (PSA) together with the possibilities of its applications, allow for evaluation of maintenance on the basis of broader scope criteria in regard to those traditionally used. The evaluate maintenance using risk based criteria, is necessary to follow a dynamic and systematic approach, in studying the maintenance strategy, to allow for updating the initial probabilistic models, for including operational changes that often take place during operation of complex facilities. This paper proposes a dynamic evaluation system of maintenance task. The system is illustrated by means of a practical example

  7. Exigências de energia para mantença e eficiência de utilização da energia metabolizável para mantença e ganho de peso de caprinos Moxotó Energy requirements for maintenance and net efficiency of metabolizable energy utilization for maintenance and weight gain of Moxotó kids

    Directory of Open Access Journals (Sweden)

    Kaliandra Souza Alves

    2008-08-01

    Full Text Available Objetivou-se avaliar as exigências líquidas de energia para mantença e as eficiências de utilização da energia metabolizável (EUEM para mantença (km e ganho de peso (kf. Utilizaram-se 26 animais da raça Moxotó, machos não-castrados com peso vivo (PV médio inicial de 15 kg e 7 a 8 meses de idade, alimentados com dieta contendo 2,6 Mcal de energia metabolizável. No início do experimento, seis animais foram abatidos e serviram como referência para estimativa da composição corporal e do peso de corpo vazio (PCVZ iniciais. Posteriormente, os animais foram distribuídos inteiramente ao acaso em grupos homogêneos de quatro animais, um para cada nível de consumo: alimentação à vontade (AV e alimentação restrita (85, 70 e 55% do consumido pelo grupo que recebeu alimentação à vontade. No momento em que o PV dos animais que recebiam alimentação à vontade se aproximava de 25 kg, o grupo era abatido. As exigências líquidas de energia para mantença foram estimadas pelas relações logarítmica ou exponencial da produção de calor (PC e o consumo de energia metabolizável (CEM. As km e kf foram calculadas como a relação entre a energia líquida da dieta para ganho ou mantença e a concentração de energia metabolizável das dietas. Posteriormente, estimaram-se as exigências de EM e NDT. A exigência de energia líquida para mantença, de 55,11 kcal/kgPCVZ0,75, foi próxima ao predito pelas normas norte-americanas para essa espécie. Esse valor é considerado baixo se comparado aos reportados na literatura brasileira pesquisada. A km estimada foi de 0,57 e as kf para as concentrações de 2,99; 2,95; 2,56 e 2,5 Mcal/kg de MS foram de 0,22; 0,19; 0,28 e 0,36, respectivamente.Twenty-six Moxotó non-castrated male kids (averaging 15 kg of initial live weight (LW and 6-8 months old fed a diet with 2.6 Mcal of metabolizable energy were used to predict the net energy requirements for maintenance and net efficiency of

  8. Performance-based inspection and maintenance strategies

    International Nuclear Information System (INIS)

    Vesely, W.E.

    1995-01-01

    Performance-based inspection and maintenance strategies utilize measures of equipment performance to help guide inspection and maintenance activities. A relevant measure of performance for safety system components is component unavailability. The component unavailability can also be input into a plant risk model such as a Probabilistic Risk Assessment (PRA) to determine the associated plant risk performance. Based on the present and projected unavailability performance, or the present and projected risk performance, the effectiveness of current maintenance activities can be evaluated and this information can be used to plan future maintenance activities. A significant amount of information other than downtimes or failure times is collected or can be collected when an inspection or maintenance is conducted which can be used to estimate the component unavailability. This information generally involves observations on the condition or state of the component or component piecepart. The information can be detailed such as the amount of corrosion buildup or can be general such as the general state of the component described as ' high degradation', ' moderate degradation', or ' low degradation'. Much of the information collected in maintenance logs is qualitative and fuzzy. As part of an NRC Research program on performance-based engineering modeling, approaches have been developed to apply Fuzzy Set Theory to information collected on the state of the component to determine the implied component or component piecepart unavailability. Demonstrations of the applications of Fuzzy Set Theory are presented utilizing information from plant maintenance logs. The demonstrations show the power of Fuzzy Set Theory in translating engineering information to reliability and risk implications

  9. A proactive condition-based maintenance strategy with both perfect and imperfect maintenance actions

    International Nuclear Information System (INIS)

    Do, Phuc; Voisin, Alexandre; Levrat, Eric; Iung, Benoit

    2015-01-01

    This paper deals with a proactive condition-based maintenance (CBM) considering both perfect and imperfect maintenance actions for a deteriorating system. Perfect maintenance actions restore completely the system to the ‘as good as new’ state. Their related cost are however often high. The first objective of the paper is to investigate the impacts of imperfect maintenance actions. In fact, both positive and negative impacts are considered. Positive impact means that the imperfect maintenance cost is usually low. Negative impact implies that (i) the imperfect maintenance restores a system to a state between good-as-new and bad-as-old and (ii) each imperfect preventive action may accelerate the speed of the system's deterioration process. The second objective of the paper is to propose an adaptive maintenance policy which can help to select optimally maintenance actions (perfect or imperfect actions), if needed, at each inspection time. Moreover, the time interval between two successive inspection points is determined according to a remaining useful life (RUL) based-inspection policy. To illustrate the use of the proposed maintenance policy, a numerical example finally is introduced. - Highlights: • A new imperfect maintenance model for deterioration system is proposed. • Both positive and negative impacts of an imperfect maintenance action are investigated. • An adaptive condition-based maintenance policy is introduced. • The optimal number of useful imperfect maintenance actions for each life cycle is optimally provided

  10. The influence of condition-based maintenance on workforce planning and maintenance scheduling

    NARCIS (Netherlands)

    Koochaki, Javid; Bokhorst, Jos A. C.; Wortmann, Hans; Klingenberg, Warse

    2013-01-01

    Condition-based maintenance (CBM) is generally considered an attractive maintenance policy for a single component: it uses the operating condition of the component to predict a failure event and therefore tries to avoid any unplanned downtime and unnecessary maintenance activities. However,

  11. Risk-based maintenance modeling. Prioritization of maintenance importances and quantification of maintenance effectiveness

    Energy Technology Data Exchange (ETDEWEB)

    Vesely, W.E.; Rezos, J.T. [Science Applications International Corp., Dublin, OH (United States)

    1995-09-01

    This report describes methods for prioritizing the risk importances of maintenances using a Probabilistic Risk Assessment (PRA). Approaches then are described for quantifying their reliability and risk effects. Two different PRA importance measures, minimal cutset importances and risk reduction importances, were used to prioritize maintenances; the findings show that both give similar results if appropriate criteria are used. The justifications for the particular importance measures also are developed. The methods developed to quantify the reliability and risk effects of maintenance actions are extensions of the usual reliability models now used in PRAs. These extended models consider degraded states of the component, and quantify the benefits of maintenance in correcting degradations and preventing failures. The negative effects of maintenance, including downtimes, also are included. These models are specific types of Markov models. The data for these models can be obtained from plant maintenance logs and from the Nuclear Plant Reliability Data System (NPRDS). To explore the potential usefulness of these models, the authors analyzed a range of postulated values of input data. These models were used to examine maintenance effects on a components reliability and performance for various maintenance programs and component data. Maintenance schedules were analyzed to optimize the component`s availability. In specific cases, the effects of maintenance were found to be large.

  12. Cost savings from performance-based maintenance contracting

    NARCIS (Netherlands)

    Straub, A.

    2009-01-01

    New procurement approaches combined with performance-based building approaches should reduce costs, but empirical qualitative and quantitative studies are lacking. Performance-based maintenance contracts give maintenance suppliers incentives to improve their way of working. Innovative,

  13. 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

  14. 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

  15. Evaluating Functional and Structural Condition Based Maintenances of Airfield Pavements

    Directory of Open Access Journals (Sweden)

    Tarefder R.

    2013-01-01

    Full Text Available This study evaluates airfield pavements’ functional- and structural-condition to determine the most economical maintenance method. As a part of the analysis, Pavement Condition Index (PCI for several runways, taxiways, and aprons has been determined by MicroPAVER. Structural evaluation of airport pavements has been performed by Falling Weight Deflectometer (FWD test. Evaluation of Layer Moduli and Overlay Design (ELMOD also determines the required overlay thickness based on the E-values, i.e. FWD data analysis. Damage analysis determines the time of repeated overlay application. In addition, functional parameters have been included to determine the time of functional maintenance. Maintenance and rehabilitation alternatives have been selected to develop different program strategies. Life Cycle Cost Analysis (LCCA has been performed to determine the maintenance cost. Structural condition based maintenance cost is compared to functional condition based maintenance cost. Comparison shows that structural condition based approach yields cheaper maintenance strategies than functional condition based maintenance approach.

  16. Virtual maintenance technology for reactor system based on PPR technology

    International Nuclear Information System (INIS)

    Wu Yaxiang; Ma Baiyong

    2009-01-01

    Based on the Product, Process and Resources (PPR) technology, the establishing technology of virtual maintenance environment for the reactor system and the process structure tree for virtual maintenance is studied, and the flow for the maintainability design and simulation for reactor system is put forward. Based on the subsection simulation of maintenance process and layered design of maintenance actions, the leveled structure of the reactor system virtual maintenance task is studied. The relation for the data of product, process and resource is described by Plan Evaluation and Review Technology (PERT) diagram to define the maintenance operation. (authors)

  17. Structuring AHP-based maintenance policy selection

    NARCIS (Netherlands)

    Goossens, Adriaan; Basten, Robertus Johannes Ida; Hummel, J. Marjan; van der Wegen, Leonardus L.M.

    2015-01-01

    We aim to structure the maintenance policy selection process for ships, using the Analytic Hierarchy Process (AHP). Maintenance is an important contributor to reach the intended life-time of capital technical assets, and it is gaining increasing interest and relevance. A maintenance policy is a

  18. A COMPUTER BASED MAINTENANCE MANAGEMENT SYSTEM ...

    African Journals Online (AJOL)

    ... programs to schedule for maintenance or replacement of machines has been designed such that it enables the maintenance department control all jobs associated with plant maintenance and breakdown. It predicts the time to failure of designated plants and caters for the replacement analysis of some capital equipment.

  19. Risk Based Maintenance of Offshore Wind Turbines Using Bayesian Networks

    DEFF Research Database (Denmark)

    Nielsen, Jannie Jessen; Sørensen, John Dalsgaard

    2010-01-01

    such that the preventive maintenance effort is balanced against the costs to corrective maintenance including indirect costs to reduced production. The basis for the optimization is the risk based Bayesian decision theory. The method is demonstrated through an application example....

  20. The influence of practical factors on the benefits of condition-based maintenance over time-based maintenance

    NARCIS (Netherlands)

    de Jonge, Bram; Teunter, Ruud; Tinga, Tiedo

    2017-01-01

    Recent developments in condition monitoring technology have led to an ongoing shift from time-based maintenance (TBM) to condition-based maintenance (CBM). Although CBM allows for more effectively planned maintenance actions, its relative performance strongly depends on the behavior of the

  1. Exigência de energia de mantença e composição corporal e do ganho de vacas de corte adultas de três grupos genéticos confinadas Maintenance energy requirements and body and gain composition of adults beef cows from three genetic groups

    Directory of Open Access Journals (Sweden)

    João Gomes de Siqueira

    2007-12-01

    Full Text Available Neste trabalho, foram estimadas as exigências de mantença de energia líquida (ELm e metabolizável (EMm e as mudanças na composição corporal e no ganho de vacas adultas não-gestantes e não-lactantes confinadas. Foram utilizadas 36 vacas, 12 Nelore (NEL, 12 F1 Pardo-Suíço-Nelore (PSN e 12 F1 Red Angus-Nelore (RAN. As alterações na composição corporal dos animais durante o período experimental foram estimadas utilizando-se a técnica do abate comparativo: quatro animais de cada grupo genético foram alocados, aleatoriamente, nos tratamentos abate inicial (AI, alimentação restrita (AR e alimentação ad libitum (AL. Os animais AR receberam, no período experimental, níveis de proteína e energia 15% acima da mantença e os AL, ração ad libitum, para ganho de 1,1 kg/dia. Os animais AI foram abatidos no início do experimento e os AR e AL 120 dias depois. Em todos os animais abatidos, foram estimadas as proporções corporais dos tecidos muscular, adiposo e ósseo, além dos conteúdos corporais de proteína, gordura e energia. Na estimação da ELm e da EMm, foram empregados modelos linear e não-linear. Os grupos genéticos não diferiram quanto às exigências de ELm e EMm, expressas em peso vivo em jejum (kcal/kg0,75/dia PVJ. Quando utilizados os modelos linear e não-linear, os valores de ELm encontrados foram de 80,7 e 83,6 kcal/kg0,75/dia PVJ e os de EMm, 109,9 e 128,0 kcal/kg0,75/dia PVJ, respectivamente. Os conteúdos de proteína por unidade de peso corpo vazio (PCVZ e do ganho (GPCVZ não diferiram entre os grupos genéticos, porém, os animais NEL apresentaram maior concentração de gordura e energia por kg PCVZ e GPVCZ para mesmo peso vivo.This research aimed to estimate the maintenance requirements of net energy (NEm and metabolizable energy (MEm, and the changes in body and gain composition of confined adults non-pregnant and non-lactant beef cows. Thirty six cows were used, 12 were Nellore (NEL, 12 F1 Brown Swiss

  2. 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

  3. Simulation based comparison of predictive maintenance policies

    NARCIS (Netherlands)

    Tinga, Tiedo; Janssen, R.H.P.; Steenbergen, R.; van Gelder, P.

    2013-01-01

    When an asset is operated in variable conditions, its operational efficiency can be improved significantly when the maintenance is performed in a dynamic manner. This means that variations in usage and operating environment are taken into account when deciding on the length of the maintenance

  4. Eficiência de utilização da energia metabolizável para mantença e ganho de peso e exigências de energia metabolizável e de nutrientes digestíveis totais de bovinos Nelore, não-castrados Efficiency of metabolizable energy utilization for maintenance and weight gain and requirements of metabolizable energy and total digestible nutrients of Nellore bulls

    Directory of Open Access Journals (Sweden)

    Antonia Sherlânea Chaves Véras

    2001-06-01

    Full Text Available Este trabalho foi conduzido para estimar as eficiências de utilização da energia metabolizável (EUEM para mantença (km e ganho de peso (kf e as exigências de energia metabolizável (EM e nutrientes digestíveis totais (NDT de bovinos Nelore, não-castrados. Utilizaram-se 35 animais com idade e peso médios de 20 meses e 330 kg. Após período de adaptação (40 dias, cinco animais foram abatidos para servir como referência; os demais foram distribuídos, em delineamento inteiramente casualizado, nos tratamentos (12,5; 25,0; 37,5; 50,0; 62,5; e 75,0% de concentrado com base na matéria seca. A estimativa das kf foi efetuada a partir da regressão entre os teores de energia líquida para ganho, em função da EM da dieta, e também agrupando-se os dados relativos aos animais do presente trabalho e os referentes a 29 bovinos F1 Simental x Nelore. As kf também foram estimadas como o coeficiente da regressão linear entre a energia retida (ER e o consumo de EM (CEM. A km estimada foi de 0,56. As kf estimadas utilizando-se a primeira metodologia foram de 0,45; 0,35; 0,54; 0,50; e 054, respectivamente, para as concentrações de 2,11; 2,35; 2,51; 2,59; e 2,52 Mcal/kg de MS. As kf estimadas por meio da segunda metodologia foram 0,32; 0,33; 0,44; 0,49; e 0,69, respectivamente. Os requisitos de EM e NDT para mantença de um animal pesando 400 kg de PV foram de 11,94 Mcal/kgGPCVZ e 3,30 kg/kgGPCVZ, respectivamente; enquanto para ganho de peso, os requisitos para dietas com 2,4 Mcal/kg de MS, foram 9,84 Mcal/kg GPCVZ e 2,72 kg/GPCVZ. Para dietas com concentração de EM de 2,6 Mcal/kg de MS, os requerimentos de EM e NDT foram, respectivamente, 7,28 Mcal/kg GPCVZ e 2,01 kg/GPCVZ.This work was carried out to estimate the efficiency of metabolizable energy utilization (EMEU for maintenance (km and weight gain (kf and the requirements of metabolizable energy (ME and total digestible nutrients (TDN of Nellore bulls. Thirty-five animals, averaging 330 kg

  5. Maintenance Optimization based on Mathematical Modeling

    NARCIS (Netherlands)

    de Jonge, Bram

    2017-01-01

    Due to an increasingly competitive marketplace and an ongoing shift from labor intensive to technology intensive industries, the importance of effectively planned and performed maintenance activities is growing. Because consequences of equipment failures are often severe, it is generally preferred

  6. Information-Based Maintenance Optimization with Focus on Predictive Maintenance (Informatiegebaseerde onderhoudsoptimalisatie met focus op predictief onderhoud)

    OpenAIRE

    Van Horenbeek, Adriaan

    2013-01-01

    This dissertation presents an information-based maintenance optimization methodology for physical assets; with focus on, but not limited to, predictive maintenance (PdM). The overall concept of information-based maintenance is that of updating maintenance decisions based on evolving knowledge of operation history and anticipated usage of the machinery, as well as the physics and dynamics of material degradation in critical machinery components. Within this concept, predictive maintenance is a...

  7. A condition-based maintenance policy for stochastically deteriorating systems

    International Nuclear Information System (INIS)

    Grall, A.; Berenguer, C.; Dieulle, L.

    2002-01-01

    We focus on the analytical modeling of a condition-based inspection/replacement policy for a stochastically and continuously deteriorating single-unit system. We consider both the replacement threshold and the inspection schedule as decision variables for this maintenance problem and we propose to implement the maintenance policy using a multi-level control-limit rule. In order to assess the performance of the proposed maintenance policy and to minimize the long run expected maintenance cost per unit time, a mathematical model for the maintained system cost is derived, supported by the existence of a stationary law for the maintained system state. Numerical experiments illustrate the performance of the proposed policy and confirm that the maintenance cost rate on an infinite horizon can be minimized by a joint optimization of the maintenance structure thresholds, or equivalently by a joint optimization of a system replacement threshold and the aperiodic inspection schedule

  8. Optimizing block-based maintenance under random machine usage

    NARCIS (Netherlands)

    de Jonge, Bram; Jakobsons, Edgars

    Existing studies on maintenance optimization generally assume that machines are either used continuously, or that times until failure do not depend on the actual usage. In practice, however, these assumptions are often not realistic. In this paper, we consider block-based maintenance optimization

  9. Model based decision support for planning of road maintenance

    NARCIS (Netherlands)

    van Harten, Aart; Worm, J.M.; Worm, J.M.

    1996-01-01

    In this article we describe a Decision Support Model, based on Operational Research methods, for the multi-period planning of maintenance of bituminous pavements. This model is a tool for the road manager to assist in generating an optimal maintenance plan for a road. Optimal means: minimising the

  10. Risk-based Operation and Maintenance of Offshore Wind Turbines

    DEFF Research Database (Denmark)

    Sørensen, John Dalsgaard

    2009-01-01

    For offshore wind turbines costs to operation and maintenance are substantial. This paper describes a risk-based lifecycle approach for optimal planning of operation and maintenance. The approach is based on pre-posterior Bayesian decision theory. Deterioration mechanisms such as fatigue, corrosion......, wear and erosion are associated with significant uncertainty. Observations of the degree of damage can increase the reliability of predictions, especially in connection with condition-based maintenance. The approach can be used for gearboxes, generators, cracks, corrosion, etc. The paper also describes...

  11. Risk-Based Operation and Maintenance of Offshore Wind Turbines

    DEFF Research Database (Denmark)

    Nielsen, Jannie Jessen; Sørensen, John Dalsgaard

    2009-01-01

    , wear and erosion are associated with significant uncertainty. Observations of the degree of damage can increase the reliability of predictions, especially in connection with condition-based maintenance. The approach can be used for gearboxes, generators, cracks, corrosion, etc. The paper also describes......For offshore wind turbines costs to operation and maintenance are substantial. This paper describes a risk-based lifecycle approach for optimal planning of operation and maintenance. The approach is based on pre-posterior Bayesian decision theory. Deterioration mechanisms such as fatigue, corrosion...

  12. A knowledge-based assistant for valve maintenance planning

    International Nuclear Information System (INIS)

    Winter, M.J.; Danofsky, R.A.; Spinrad, B.I.; Howard, K.

    1987-01-01

    A knowledge-based program is being developed to assist engineers in maintenance planning for safety related, motor-operated valves at a boiling water reactor. The purpose of this project is to develop the general framework for a prototype system that demonstrates the capabilities for diagnosing valve symptoms and prescribing corrective maintenance, completing a portion of the Corrective Maintenance Action Request (CMAR) form which must be prepared for each job, and managing an interactive valve data base. Minimizing user input and providing output in a form that is familiar to the maintenance planning engineer are important goals for the program. This paper describes the present features of the valve maintenance advisory system which is currently being tested

  13. Risk-based maintenance-Techniques and applications

    International Nuclear Information System (INIS)

    Arunraj, N.S.; Maiti, J.

    2007-01-01

    Plant and equipment, however well designed, will not remain safe or reliable if it is not maintained. The general objective of the maintenance process is to make use of the knowledge of failures and accidents to achieve the possible safety with the lowest possible cost. The concept of risk-based maintenance was developed to inspect the high-risk components usually with greater frequency and thoroughness and to maintain in a greater manner, to achieve tolerable risk criteria. Risk-based maintenance methodology provides a tool for maintenance planning and decision making to reduce the probability of failure of equipment and the consequences of failure. In this paper, the risk analysis and risk-based maintenance methodologies were identified and classified into suitable classes. The factors affecting the quality of risk analysis were identified and analyzed. The applications, input data and output data were studied to understand their functioning and efficiency. The review showed that there is no unique way to perform risk analysis and risk-based maintenance. The use of suitable techniques and methodologies, careful investigation during the risk analysis phase, and its detailed and structured results are necessary to make proper risk-based maintenance decisions

  14. Risk-Based Operation and Maintenance of Offshore Wind Turbines

    DEFF Research Database (Denmark)

    Nielsen, Jannie Sønderkær

    , but presently maintenance is not planned using advanced methods taking all available information into account in a consistent manner. Maintenance decisions can be made based on risk-based methods, where the total expected life cycle costs are minimized. Methods have been developed for assessing the corrective...... maintenance planning, taking into account monitoring, inspections, preventive repairs and corrective repairs. This can be done using methods developed from a Bayesian perspective. Such methods have been developed for use in the oil and gas industry under the name Risk-Based Inspection (RBI), and are based...... to oil and gas structures. In addition, condition monitoring systems are often available, and the information should be taken into account when making decisions. In this thesis, methods for risk-based maintenance planning using Bayesian methods are investigated, with the aim of making optimal decisions...

  15. Knowledge Management for Large Scale Condition Based Maintenance

    Data.gov (United States)

    National Aeronautics and Space Administration — This presentation will review the use of knowledge management in the development and support of Condition Based Maintenance (CBM) systems for complex systems with...

  16. Risk-based Operation and Maintenance for Offshore Wind Turbines

    DEFF Research Database (Denmark)

    Sørensen, John Dalsgaard; Nielsen, Jannie Jessen

    2011-01-01

    and are often the driving mechanisms for failures / faults that need maintenance. Observations of the degree of damage can increase the reliability of predictions and decrease the costs of OM if integrated in a risk-based framework theoretically based on pre-posterior Bayesian decision theory. The mathematical......For offshore wind turbines, costs to Operation and Maintenance (OM) are substantial, and can be expected to increase when wind farms are placed at deeper water depths and in more harsh environments. Traditional strategies for OM include corrective and preventive (scheduled and condition......-based) maintenance strategies. This paper describes a risk-based life-cycle approach for optimal planning of OM and design of offshore wind turbines. Damage accumulation models used to describe deterioration mechanisms such as fatigue, corrosion, wear and erosion are associated with significant uncertainty...

  17. [Web-based support system for medical device maintenance].

    Science.gov (United States)

    Zhao, Jinhai; Hou, Wensheng; Chen, Haiyan; Tang, Wei; Wang, Yihui

    2015-01-01

    A Web-based technology system was put forward aiming at the actual problems of the long maintenance cycle and the difficulties of the maintenance and repairing of medical equipments. Based on analysis of platform system structure and function, using the key technologies such as search engine, BBS, knowledge base and etc, a platform for medical equipment service technician to use by online or offline was designed. The platform provides users with knowledge services and interactive services, enabling users to get a more ideal solution.

  18. The International Coal Statistics Data Base program maintenance guide

    International Nuclear Information System (INIS)

    1991-06-01

    The International Coal Statistics Data Base (ICSD) is a microcomputer-based system which contains information related to international coal trade. This includes coal production, consumption, imports and exports information. The ICSD is a secondary data base, meaning that information contained therein is derived entirely from other primary sources. It uses dBase III+ and Lotus 1-2-3 to locate, report and display data. The system is used for analysis in preparing the Annual Prospects for World Coal Trade (DOE/EIA-0363) publication. The ICSD system is menu driven and also permits the user who is familiar with dBase and Lotus operations to leave the menu structure to perform independent queries. Documentation for the ICSD consists of three manuals -- the User's Guide, the Operations Manual, and the Program Maintenance Manual. This Program Maintenance Manual provides the information necessary to maintain and update the ICSD system. Two major types of program maintenance documentation are presented in this manual. The first is the source code for the dBase III+ routines and related non-dBase programs used in operating the ICSD. The second is listings of the major component database field structures. A third important consideration for dBase programming, the structure of index files, is presented in the listing of source code for the index maintenance program. 1 fig

  19. Quality assurance of performance-based maintenance partnerships

    NARCIS (Netherlands)

    Straub, A.; Van Mossel, H.J.

    2006-01-01

    Dutch housing associations develop new procurement methods for maintenance of their housing stock, namely performance-based partnership forms. Partnership forms promise the optimal use of know-how of parties involved. For contractors a performance-based approach means major changes in working

  20. Remediation of Gremikha Coastal maintenance base - status of the project

    Energy Technology Data Exchange (ETDEWEB)

    Pillette-Cousin, L. [AREVA TA, 91 - Gif-sur-Yvette (France); Stepennov, B.S. [Kurchatov Institute, Moscow (Russian Federation); Gorbatchev, A. [CEA Saclay, 91 - Gif sur Yvette (France)

    2008-07-01

    The former coastal maintenance base in Gremikha is located in the Kola Peninsula, along the Barents Sea, about 300 km east from Murmansk. There is no road or railway to get there, therefore the only possible connection is either by sea or by helicopter. Remediation of the Gremikha coastal maintenance base (CMB) is now one of the main priorities for Rosatom (the Agency for Atomic Energy of the Russian Federation) because nuclear and radioactive waste are currently stored in conditions which do not meet the up-to-date safety and regulatory requirements and it might represent an environmental hazard and a risk of misappropriation of the nuclear material stored there. (authors)

  1. The influence of practical factors on the benefits of condition-based maintenance over time-based maintenance

    International Nuclear Information System (INIS)

    Jonge, Bram de; Teunter, Ruud; Tinga, Tiedo

    2017-01-01

    Recent developments in condition monitoring technology have led to an ongoing shift from time-based maintenance (TBM) to condition-based maintenance (CBM). Although CBM allows for more effectively planned maintenance actions, its relative performance strongly depends on the behavior of the deterioration process, the severity of failures, the required setup time, the accuracy of the condition measurements, and the amount of randomness in the deterioration level at which failure occurs. The contribution of this paper is twofold. First, we review studies that compare CBM with TBM, and studies that consider the above factors in combination with a CBM model. Second, whereas existing studies confine themselves to a few examples, we perform a numerical investigation to derive insights on the effects of the various characteristics on the relative benefit of CBM. The results can be used by companies to decide what factors are most important when considering to implement CBM, and to assess whether the benefit of CBM during the operational phase outweighs the additional costs during the life cycle of equipment. This study allows for follow-up research to quantify and generalize the insights obtained, and to analyze interaction effects. - Highlights: • Condition-based maintenance (CBM) is compared with time-based maintenance (TBM). • An extensive literature review is provided. • Insights are derived on the effects of various characteristics on the relative benefit of CBM.

  2. Performance-based maintenance procurement by Dutch housing associations

    NARCIS (Netherlands)

    Straub, A.

    2004-01-01

    OTB Research institute has established a long-term research program to performance-based maintenance procurement in the technical management of housing stock. Stakeholders: housing associations, contractors and the Dutch Building Research Foundation are directly involved in this research program.

  3. 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...

  4. Risk-Based Operation and Maintenance Using Bayesian Networks

    DEFF Research Database (Denmark)

    Nielsen, Jannie Jessen; Sørensen, John Dalsgaard

    2011-01-01

    This paper describes how risk-based decision making can be used for maintenance planning of components exposed to degradation such as fatigue in offshore wind turbines. In fatigue models, large epistemic uncertainties are usually present. These can be reduced if monitoring results are used...

  5. Index : A Rule Based Expert System For Computer Network Maintenance

    Science.gov (United States)

    Chaganty, Srinivas; Pitchai, Anandhi; Morgan, Thomas W.

    1988-03-01

    Communications is an expert intensive discipline. The application of expert systems for maintenance of large and complex networks, mainly as an aid in trouble shooting, can simplify the task of network management. The important steps involved in troubleshooting are fault detection, fault reporting, fault interpretation and fault isolation. At present, Network Maintenance Facilities are capable of detecting and reporting the faults to network personnel. Fault interpretation refers to the next step in the process, which involves coming up with reasons for the failure. Fault interpretation can be characterized in two ways. First, it involves such a diversity of facts that it is difficult to predict. Secondly, it embodies a wealth of knowledge in the form of network management personnel. The application of expert systems in these interpretive tasks is an important step towards automation of network maintenance. In this paper, INDEX (Intelligent Network Diagnosis Expediter), a rule based production system for computer network alarm interpretation is described. It acts as an intelligent filter for people analyzing network alarms. INDEX analyzes the alarms in the network and identifies proper maintenance action to be taken.The important feature of this production system is that it is data driven. Working memory is the principal data repository of production systems and its contents represent the current state of the problem. Control is based upon which productions match the constantly changing working memory elements. Implementation of the prototype is in OPS83. Major issues in rule based system development such as rule base organization, implementation and efficiency are discussed.

  6. 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.

  7. Condition-based maintenance for complex systems : Coordinating maintenance and logistics planning for the process industries

    NARCIS (Netherlands)

    Olde Keizer, Minou Catharina Anselma

    2016-01-01

    Maintenance planning in the process industries is extremely complex for various reasons. Plants often run nonstop, allowing little time for performing preventive maintenance. Failures should be prevented, however, as they can lead to system downtime and high losses of revenue. Corrective maintenance

  8. Influencing factors for condition-based maintenance in railway tracks using knowledge-based approach

    NARCIS (Netherlands)

    Jamshidi, A.; Hajizadeh, S.; Naeimi, M.; Nunez Vicencio, Alfredo; Li, Z.

    2017-01-01

    In this paper, we present a condition-based maintenance decision method using
    knowledge-based approach for rail surface defects. A railway track may contain a considerable number of surface defects which influence track maintenance decisions. The proposed method is based on two sets of

  9. Laser based maintenance technology for PWR power plants

    International Nuclear Information System (INIS)

    Itaru Chida; Masaki Yoda; Naruhiko Mukai; Yuji Sano; Makoto Ochiai; Takahiro Miura; Ryoichi Saeki

    2005-01-01

    Stress corrosion cracking (SCC) is the major factor to reduce the reliability of aged reactor components. Toshiba has developed various laser-based maintenance technologies and already applied them to several existing nuclear power plants. Recently, we have developed the maintenance system for the inner surface of bottom-mounted instruments (BMI) of PWR plants. This system performs nondestructive testing (NDT) and preventive maintenance against SCC by using YAG lasers. Laser ultrasonic testing (LUT) has a great potential to be applied to the remote inspection of reactor components. Laser-induced surface acoustic wave (SAW) inspection system was developed by using a compact probe with a multi-mode optical fiber and an interferometer. This system is used for both detection and depth measurement of surface-breaking cracks. It is confirmed through laboratory studies that the developed system successfully detected and sized micro slits of around 1.0 mm depth on weld metal and heat-affected zone (HAZ). SCCs produced by chemical method were also tested by the system. For the preventive maintenance treatment, laser-peening (LP) technology was developed and already applied to several reactor components in operating BWR plants. LP is a novel process to improve residual stress from tensile to compressive on material surface layer by irradiating focused high-power laser pulses in water. We have developed a fiber-delivered LP (FLP) system as a preventive maintenance against SCC. For checking the effect of FLP, we carried out FLP experiments on the inner surface of a small tube-shaped Alloy 600 by using this system. After FLP, residual stress was measured by X-ray method for radial and axial directions on the inner surface of the tube, and effectiveness of stress improvement was proved. Based on these experiences, LUT and FLP were applied to Ikata unit-1 of Shikoku Electric Power Company Inc. and successfully treated the inner surface of BMIs. (authors)

  10. PROTOTYPE WEB-BASED EXPERT SYSTEM FOR FLEXIBLE PAVEMENT MAINTENANCE

    Directory of Open Access Journals (Sweden)

    ABDALRHMAN MILAD

    2017-11-01

    Full Text Available The paper describes the development of a prototype web-based expert knowledge system that can be used to maintain flexible pavement within a tropical region. This prototype system provides the advantages of using existing web-based expert system technology. Currently, deterioration of asphalt pavement layers is one of the biggest problems in Malaysia and requires maintenance to ensure that the roads remain open and able to guarantee the regularity, punctuality, and safety of all transport services. According to this process, the knowledge collection that has acquired and the date concerning to domain expert system of the development web-based system was launched with knowledge representation IF and THEN rules and coded by PHP programming. The web pages that support the user interface are created using a framework consisting of HTML, CSS, and J-Query. The prototype web-based expert system uses the knowledge of a pavement maintenance expert, or a specialist in pavement problem remediation, to emulate a portion of their professional reasoning abilities, which it can then use to assist with the maintenance of existing roads and enhance the efficiency and accuracy of the professional engineers tasked with the assessment of all available remedies. Thus, the system increases the performance level of the engineers in analysing, discerning and customising the information that will assist decision makers throughout the project, so the probability that the right decision and treatment are implemented at the right time is increased.

  11. Towards Dynamic Criticality-Based Maintenance Strategy for Industrial Assets

    OpenAIRE

    Adams, Joel; Srinivasan, Rengarajan; Parlikad, Ajith Kumar; Diaz, V; Crespo, Marquez A

    2016-01-01

    An asset’s risk is a useful indicator for determining optimal time of repair/replacement for assets in order to yield minimal operational cost of maintenance. For a successful asset management practice, asset-intensive organisations must understand the risk profile associated with their asset portfolio and how this will change over time. Unfortunately, in many risk-based asset management approaches, the only thing that is known to change in the risk profile of the asset is the likelihood (or ...

  12. Corrosion Sensor Development for Condition-Based Maintenance of Aircraft

    Directory of Open Access Journals (Sweden)

    Gino Rinaldi

    2012-01-01

    Full Text Available Aircraft routinely operate in atmospheric environments that, over time, will impact their structural integrity. Material protection and selection schemes notwithstanding, recurrent exposure to chlorides, pollution, temperature gradients, and moisture provide the necessary electrochemical conditions for the development and profusion of corrosion in aircraft structures. For aircraft operators, this becomes an important safety matter as corrosion found in a given aircraft must be assumed to be present in all of that type of aircraft. This safety protocol and its associated unscheduled maintenance requirement drive up the operational costs of the fleet and limit the availability of the aircraft. Hence, there is an opportunity at present for developing novel sensing technologies and schemes to aid in shifting time-based maintenance schedules towards condition-based maintenance procedures. In this work, part of the ongoing development of a multiparameter integrated corrosion sensor is presented. It consists of carbon nanotube/polyaniline polymer sensors and commercial-off-the-shelf sensors. It is being developed primarily for monitoring environmental and material factors for the purpose of providing a means to more accurately assess the structural integrity of aerospace aluminium alloys through fusion of multiparameter sensor data. Preliminary experimental test results are presented for chloride ion concentration, hydrogen gas evolution, humidity variations, and material degradation.

  13. Improvement of testing and maintenance based on fault tree analysis

    International Nuclear Information System (INIS)

    Cepin, M.

    2000-01-01

    Testing and maintenance of safety equipment is an important issue, which significantly contributes to safe and efficient operation of a nuclear power plant. In this paper a method, which extends the classical fault tree with time, is presented. Its mathematical model is represented by a set of equations, which include time requirements defined in the house event matrix. House events matrix is a representation of house events switched on and off through the discrete points of time. It includes house events, which timely switch on and off parts of the fault tree in accordance with the status of the plant configuration. Time dependent top event probability is calculated by the fault tree evaluations. Arrangement of components outages is determined on base of minimization of mean system unavailability. The results show that application of the method may improve the time placement of testing and maintenance activities of safety equipment. (author)

  14. Composição corporal e exigências nutricionais em cálcio e fósforo para ganho e mantença de cordeiros Santa Inês dos 15 kg aos 25 kg de peso vivo Body composition and requirements for calcium and phosphorus for gain and maintenance of Santa Ines lambs from 15 to 25 kg of body weight

    Directory of Open Access Journals (Sweden)

    Luciana Castro Geraseev

    2000-02-01

    Full Text Available RESUMO - Este trabalho foi conduzido para determinar a composição corporal e estimar as exigências de cálcio e fósforo de cordeiros da raça Santa Inês. Foram utilizados 18 cordeiros machos inteiros, com peso médio inicial de 15 kg, divididos em três grupos: seis animais abatidos no início do experimento, para avaliar o conteúdo de cálcio e fósforo corporal, servindo como animais referência para o método do abate comparativo; seis animais alimentados ad libitum; e seis com alimentação restrita (em nível de mantença + 20%. Os cordeiros que receberam dietas ad libitum e restritas entraram no experimento aos pares e foram abatidos concomitantemente, quando o primeiro atingiu 25 kg de peso vivo. A composição corporal foi estimada a partir de equações de regressão do logaritmo da quantidade de cálcio e fósforo presentes no corpo vazio, em função do logaritmo do peso corporal vazio. As exigências líquidas de mantença e o coeficiente de absorção destes minerais foram determinados a partir da correlação entre a quantidade de mineral ingerida e a quantidade retida no corpo, enquanto as exigências líquidas para o ganho em peso foram estimadas a partir da derivação de equações de predição da composição corporal. As exigências líquidas de mantença, para animais entre 15 e 25 kg de peso vivo, foram 305 mg de Ca/dia e 325 mg de P/dia e as exigências líquidas por kg de ganho de peso vivo, para animais com 15 e 25 kg de peso vivo, 11,41 e 10,33 g Ca e 5,72 e 4,94 g P, respectivamente. Os coeficientes de absorção encontrados neste trabalho foram 0,44 e 0,55 para Ca e P, respectivamente.ABSTRACT - The research was carried out to determine body composition and calcium and phosphorus requirements of Santa Ines lambs. Eighteen entire male lambs with average initial live weight of 15 kg were used. The animals were allotted to three groups: six animals were slaughtered at the beginning of the experiment, to access the

  15. Maintenance Task Data Base for Buildings: Electrical Systems

    Science.gov (United States)

    1991-05-01

    LENGTHS OF WIREWAY/BOX 0.001900 &.REMOVE LENGTHS OF WIREIJAY/SEC. 0.001900 7.REMOVE BUSHINGS 0.000400 8.REMOVE ELBOW COVERS 0.001300 9.REMOVE ELBOW BASE...0.003700 17.CUT/DEBURR LENGTH OF WIREWAY 0.004700 18INSTALL ELBOW BASE PLATE 0.002100 M9INSTALL ALL SECTIONS OF WIREWAT 0.060600 20.INSTALL 2 BUSHINGS FOR... SWITCHGEAR , MAINFR. 1200a. System: SERVICE AND DIST. Subsystem: MAIN PROTECTION EQUIP. Task Description: P PREVENTIVE MAINTENANCE AND INSPECTION Unit

  16. 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)

  17. Game-Theoretic Models for Usage-based Maintenance Contract

    Science.gov (United States)

    Husniah, H.; Wangsaputra, R.; Cakravastia, A.; Iskandar, B. P.

    2018-03-01

    A usage-based maintenance contracts with coordination and non coordination between two parties is studied in this paper. The contract is applied to a dump truck operated in a mining industry. The situation under study is that an agent offers service contract to the owner of the truck after warranty ends. This contract has only a time limit but no usage limit. If the total usage per period exceeds the maximum usage allowed in the contract, then the owner will be charged an additional cost. In general, the agent (Original Equipment Manufacturer/OEM) provides a full coverage of maintenance, which includes PM and CM under the lease contract. The decision problem for the owner is to select the best option offered that fits to its requirement, and the decision problem for the agent is to find the optimal maintenance efforts for a given price of the service option offered. We first find the optimal decisions using coordination scheme and then with non coordination scheme for both parties.

  18. 24 CFR 35.1220 - Ongoing lead-based paint maintenance activities.

    Science.gov (United States)

    2010-04-01

    ...-based paint maintenance activities into regular building operations in accordance with § 35.1355(a). ... maintenance activities. 35.1220 Section 35.1220 Housing and Urban Development Office of the Secretary... STRUCTURES Tenant-Based Rental Assistance § 35.1220 Ongoing lead-based paint maintenance activities...

  19. Clustering condition-based maintenance for a multi-unit system with aperiodic inspections

    NARCIS (Netherlands)

    Olde Keizer, Minou C.A.; Teunter, Ruud H.; Podofillini, Luca; Sudret, Bruno; Stojadinović, Božidar; Zio, Enrico; Kröger, Wolfgang

    2015-01-01

    Condition-Based Maintenance (CBM) is a predictive maintenance strategy, which bases the maintenance scheduling on condition measurements of the components. In this paper, we continue work on the CBM optimization approach proposed by Castanier, B., A. Grall & C. Bérenguer (2005). A condition-based

  20. Hypertext-based integration for nuclear plant maintenance and operations

    International Nuclear Information System (INIS)

    Tsoukalas, L.H.; Upadhyaya, B.R.

    1991-01-01

    A methodology is presented that uses fuzzy graphs in the emerging paradigm of hypertext for the purpose of integrating data, information and multifaceted knowledge resources abounding in power plant operations and maintenance. A hypertext system is viewed as a set of nodes and links where with each link we associate membership functions embodying context-dependent criteria for navigating large information spaces. A general framework for navigation is outlined and graph-theory navigational tools are developed. A numerical example and a HyperCard-based prototype for monitoring special material in the MHTGR-NPR are included. 10 refs., 12 figs

  1. Investigation of an innovative maintenance contracting strategy : the performance-based maintenance contract (PBMC).

    Science.gov (United States)

    2015-06-01

    One of the major responsibilities of state Departments of Transportation (DOTs) is to maintain their road assets so : that road users can travel cost effectively, safely, and in a timely manner. Maintenance projects can be performed : either by using...

  2. Maintenance cost optimization in condition based maintenance: a case study for critical facilities

    OpenAIRE

    Filippo De Carlo; Maria Antonietta Arleo

    2013-01-01

    The increasing availability required to industrial plants and the limited budget often existing to assure it, require a careful formulation of maintenance optimization models. This need is primary for process plants, for which minimization of stops and maximization of their availability, are essential for ensuring targeted production and, therefore, profitability. In this context, the choice of the maintenance strategy is hence fundamental, depending on the system features and then on the eff...

  3. An Intelligent Fleet Condition-Based Maintenance Decision Making Method Based on Multi-Agent

    Directory of Open Access Journals (Sweden)

    Bo Sun

    2012-01-01

    Full Text Available According to the demand for condition-based maintenance online decision making among a mission oriented fleet, an intelligent maintenance decision making method based on Multi-agent and heuristic rules is proposed. The process of condition-based maintenance within an aircraft fleet (each containing one or more Line Replaceable Modules based on multiple maintenance thresholds is analyzed. Then the process is abstracted into a Multi-Agent Model, a 2-layer model structure containing host negotiation and independent negotiation is established, and the heuristic rules applied to global and local maintenance decision making is proposed. Based on Contract Net Protocol and the heuristic rules, the maintenance decision making algorithm is put forward. Finally, a fleet consisting of 10 aircrafts on a 3-wave continuous mission is illustrated to verify this method. Simulation results indicate that this method can improve the availability of the fleet, meet mission demands, rationalize the utilization of support resources and provide support for online maintenance decision making among a mission oriented fleet.

  4. Development the conceptual design of Knowledge Based System for Integrated Maintenance Strategy and Operation

    International Nuclear Information System (INIS)

    Milana; Khan, M K; Munive, J E

    2014-01-01

    The importance of maintenance has escalated significantly by the increasing of automation in manufacturing process. This condition switches traditional maintenance perspective of inevitable cost into the business competitive driver. Consequently, maintenance strategy and operation decision needs to be synchronized to business and manufacturing concerns. This paper shows the development of conceptual design of Knowledge Based System for Integrated Maintenance Strategy and Operation (KBIMSO). The framework of KBIMSO is elaborated to show the process of how the KBIMSO works to reach the maintenance decision. By considering the multi-criteria of maintenance decision making, the KB system embedded with GAP and AHP to support integrated maintenance strategy and operation which is novel in this area. The KBIMSO is useful to review the existing maintenance system and give reasonable recommendation of maintenance decisions in respect to business and manufacturing perspective

  5. Development the conceptual design of Knowledge Based System for Integrated Maintenance Strategy and Operation

    Science.gov (United States)

    Milana; Khan, M. K.; Munive, J. E.

    2014-07-01

    The importance of maintenance has escalated significantly by the increasing of automation in manufacturing process. This condition switches traditional maintenance perspective of inevitable cost into the business competitive driver. Consequently, maintenance strategy and operation decision needs to be synchronized to business and manufacturing concerns. This paper shows the development of conceptual design of Knowledge Based System for Integrated Maintenance Strategy and Operation (KBIMSO). The framework of KBIMSO is elaborated to show the process of how the KBIMSO works to reach the maintenance decision. By considering the multi-criteria of maintenance decision making, the KB system embedded with GAP and AHP to support integrated maintenance strategy and operation which is novel in this area. The KBIMSO is useful to review the existing maintenance system and give reasonable recommendation of maintenance decisions in respect to business and manufacturing perspective.

  6. 24 CFR 35.825 - Ongoing lead-based paint maintenance and reevaluation.

    Science.gov (United States)

    2010-04-01

    ... maintenance and reevaluation. 35.825 Section 35.825 Housing and Urban Development Office of the Secretary... maintenance and reevaluation. HUD shall incorporate ongoing lead-based paint maintenance and reevaluation, in accordance with § 35.1355, into regular building operations if HUD retains ownership of the residential...

  7. The role of knowledge sharing and transactive memory system on condition based maintenance policy

    NARCIS (Netherlands)

    Koochaki, J.; Bouwhuis, I. M.

    2008-01-01

    Today, Condition Based Maintenance (CBM) has reached a sophisticated level in industry and the advantages of predictive maintenance are accepted globally. However, although lots of effort has been put into improving methods and techniques in CBM, most of predictive maintenance programs fail to

  8. A basic condition-based maintenance strategy for air-cooled turbine generators

    International Nuclear Information System (INIS)

    Laird, T.; Griffith, G.; Hoof, M.

    2005-01-01

    This paper discusses the methods of using condition-based maintenance (CBM) for turbine generators. Even though it is focused on the maintenance strategy for air-cooled generators, all types of power producers can realize benefits from a better maintenance strategy at lower costs. A reliable assessment of the actual unit condition requires detailed knowledge of the unit design, operational weaknesses, cost of maintenance and operational capabilities. (author)

  9. Reliability-Based Maintenance and Inspection Planning for Wind Turbines

    DEFF Research Database (Denmark)

    Sørensen, John Dalsgaard

    2004-01-01

    and maintenance costs, and failure costs. Different reconstruction policies in case of failure are considered, including systematic reconstruction in case of failure, no reconstruction and failure of the control system. The concept of generic inspection and maintenance planning coupled with information from...

  10. PSO Based Optimization of Testing and Maintenance Cost in NPPs

    Directory of Open Access Journals (Sweden)

    Qiang Chou

    2014-01-01

    Full Text Available Testing and maintenance activities of safety equipment have drawn much attention in Nuclear Power Plant (NPP to risk and cost control. The testing and maintenance activities are often implemented in compliance with the technical specification and maintenance requirements. Technical specification and maintenance-related parameters, that is, allowed outage time (AOT, maintenance period and duration, and so forth, in NPP are associated with controlling risk level and operating cost which need to be minimized. The above problems can be formulated by a constrained multiobjective optimization model, which is widely used in many other engineering problems. Particle swarm optimizations (PSOs have proved their capability to solve these kinds of problems. In this paper, we adopt PSO as an optimizer to optimize the multiobjective optimization problem by iteratively trying to improve a candidate solution with regard to a given measure of quality. Numerical results have demonstrated the efficiency of our proposed algorithm.

  11. Risk based test interval and maintenance optimisation - Application and uses

    International Nuclear Information System (INIS)

    Sparre, E.

    1999-10-01

    The project is part of an IAEA co-ordinated Research Project (CRP) on 'Development of Methodologies for Optimisation of Surveillance Testing and Maintenance of Safety Related Equipment at NPPs'. The purpose of the project is to investigate the sensitivity of the results obtained when performing risk based optimisation of the technical specifications. Previous projects have shown that complete LPSA models can be created and that these models allow optimisation of technical specifications. However, these optimisations did not include any in depth check of the result sensitivity with regards to methods, model completeness etc. Four different test intervals have been investigated in this study. Aside from an original, nominal, optimisation a set of sensitivity analyses has been performed and the results from these analyses have been compared to the original optimisation. The analyses indicate that the result of an optimisation is rather stable. However, it is not possible to draw any certain conclusions without performing a number of sensitivity analyses. Significant differences in the optimisation result were discovered when analysing an alternative configuration. Also deterministic uncertainties seem to affect the result of an optimisation largely. The sensitivity of failure data uncertainties is important to investigate in detail since the methodology is based on the assumption that the unavailability of a component is dependent on the length of the test interval

  12. Condition Based Maintenance of Space Exploration Vehicles Using Structural Health Monitoring, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Acellent Technologies proposes to develop an autonomous and automated diagnostic system for condition based maintenance (CBM) of safety critical structures for space...

  13. Condition Based Maintenance of Space Exploration Vehicles Using Structural Health Monitoring Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Acellent Technologies proposes to develop an autonomous and automated diagnostic system for condition based maintenance (CBM) of safety critical structures for space...

  14. Costs of performance based maintenance for local roads: Case study Albania

    Science.gov (United States)

    Jokanović, Igor; Grujić, Bojana; Zeljić, Dragana; Grujić, Žarko; Svilar, Mila

    2017-12-01

    The provision and maintenance of road infrastructure is a major global business, consequently it is essential that road maintenance services are provided in the most cost effective manner. Without regular maintenance, roads can rapidly fall into disrepair, preventing realization of the longer term impacts of road improvements on development, such as increased agricultural production and growth in school enrollment, which is of particular importance for a network of local (access) roads. Inadequate local roads maintenance in Albania is proposed to be solved by implementing performance based maintenance approach for which the costing exercise is presented within the paper.

  15. 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

  16. EFEITO DA UTILIZAÇÃO DE PROBIÓTICO À BASE DE Lactobacillus sp.SOBRE O GANHO DE PESO E DESENVOLVIMENTO DA MUCOSA INTESTINAL DE RATOS (Rattus norvergicus)

    OpenAIRE

    Elisângela Muniz de Oliveira; Marcella Nogueira do Nascimento; Cláudia Bueno Alves; Glaucia Maria Cavasin -Oliveira; Reginaldo Nassar Ferreira

    2006-01-01

    O experimento foi conduzido no Biotério Central da Universidade Federal de Goiás para avaliar o uso de probiótico a base de Lactobacillus sp. para ratos (Rattus novergicus). Um total de 30 ratos machos adultos pesando entre 221 (considerados como leves) a 221 gramas (pesados) foram alojados em gaiolas coletivas com controle de luminosidade e de temperatura. Os animais foram divididos em três tratamentos em blocos casualizados de acordo como peso vivo. Os tratamentos foram: grupo I – ração sem...

  17. Cluster based architecture and network maintenance protocol for medical priority aware cognitive radio based hospital.

    Science.gov (United States)

    Al Mamoon, Ishtiak; Muzahidul Islam, A K M; Baharun, Sabariah; Ahmed, Ashir; Komaki, Shozo

    2016-08-01

    Due to the rapid growth of wireless medical devices in near future, wireless healthcare services may face some inescapable issue such as medical spectrum scarcity, electromagnetic interference (EMI), bandwidth constraint, security and finally medical data communication model. To mitigate these issues, cognitive radio (CR) or opportunistic radio network enabled wireless technology is suitable for the upcoming wireless healthcare system. The up-to-date research on CR based healthcare has exposed some developments on EMI and spectrum problems. However, the investigation recommendation on system design and network model for CR enabled hospital is rare. Thus, this research designs a hierarchy based hybrid network architecture and network maintenance protocols for previously proposed CR hospital system, known as CogMed. In the previous study, the detail architecture of CogMed and its maintenance protocols were not present. The proposed architecture includes clustering concepts for cognitive base stations and non-medical devices. Two cluster head (CH selector equations are formulated based on priority of location, device, mobility rate of devices and number of accessible channels. In order to maintain the integrity of the proposed network model, node joining and node leaving protocols are also proposed. Finally, the simulation results show that the proposed network maintenance time is very low for emergency medical devices (average maintenance period 9.5 ms) and the re-clustering effects for different mobility enabled non-medical devices are also balanced.

  18. Design of Mobile Operation and Maintenance System Based on Power GIS and GPS

    Directory of Open Access Journals (Sweden)

    Jing TAO

    2017-01-01

    Full Text Available In order to solve the low efficiency of operation and maintenance and the problems of management coordination caused by the coexistence of off-line operation and maintenance and multi system coexistence in current power telecommunication operation and maintenance, this paper proposes a mobile operation and maintenance system based on power GIS and GPS location technology. The system is based on the C/S architecture, and the mobile operation and maintenance terminal is connected with the operation and maintenance management terminal through wireless and wired network. In addition to meeting basic business requirements, the system integrates power GIS functions to visually demonstrate communication resources, personnel, and failures. The staff can use the wireless mobile terminal which integrated GPS module for to operate and maintain, and can locate accurately in real time.

  19. Development and Optimization of a Condition-Based Maintenance Policy with Sustainability Requirements for Production System

    Directory of Open Access Journals (Sweden)

    Aiping Jiang

    2018-01-01

    Full Text Available In the field of condition-based maintenance, maintenance costs and system reliability criteria are the primary considerations for traditional maintenance management. These methods lack consideration of the environmental impact caused by equipment degradation, such as excessive emissions and energy consumption. In addition, because equipment degradation has various impacts on the ecological environment, companies with excessive emissions and energy consumption can receive huge fines, making it of great value to study ecoconscious maintenance strategies. In this paper, we propose a condition-based maintenance strategy considering energy consumption and carbon dioxide emissions. The major objective of the research is to extend a model which integrates ecological aspects with maintenance decision-making and optimization. The simulation and sensitivity analyses conducted verify that the model proposed can minimize total costs, as well as the environmental impact.

  20. Risk-Based Predictive Maintenance for Safety-Critical Systems by Using Probabilistic Inference

    Directory of Open Access Journals (Sweden)

    Tianhua Xu

    2013-01-01

    Full Text Available Risk-based maintenance (RBM aims to improve maintenance planning and decision making by reducing the probability and consequences of failure of equipment. A new predictive maintenance strategy that integrates dynamic evolution model and risk assessment is proposed which can be used to calculate the optimal maintenance time with minimal cost and safety constraints. The dynamic evolution model provides qualified risks by using probabilistic inference with bucket elimination and gives the prospective degradation trend of a complex system. Based on the degradation trend, an optimal maintenance time can be determined by minimizing the expected maintenance cost per time unit. The effectiveness of the proposed method is validated and demonstrated by a collision accident of high-speed trains with obstacles in the presence of safety and cost constrains.

  1. Regulatory requirements related to risk-based inspection and maintenance

    International Nuclear Information System (INIS)

    Schroeder, H.C.; Kauer, R.

    2003-01-01

    By asking the question why new inspection and maintenance strategies have to be developed one can often be made aware that there is always a continue demand for cost reduction and optimisation. In this framework, general trends involving staff reduction, outsourcing, benchmarking etc. can often be observed nearly everywhere. Since inspection and maintenance are amongst the few cost factors, which could be actively influenced in the short term, and in combination with the recent regulatory fundamental changes (e.g. PED) yielding to considerably greater responsibilities for the operator of a plant, also the demand for documentation and comprehensibility of measures will increase. (orig.)

  2. The safety monitor and RCM workstation as complementary tools in risk based maintenance optimization

    International Nuclear Information System (INIS)

    Rawson, P.D.

    2000-01-01

    Reliability Centred Maintenance (RCM) represents a proven technique for rendering maintenance activities safer, more effective, and less expensive, in terms of systems unavailability and resource management. However, it is believed that RCM can be enhanced by the additional consideration of operational plant risk. This paper discusses how two computer-based tools, i.e., the RCM Workstation and the Safety Monitor, can complement each other in helping to create a living preventive maintenance strategy. (author)

  3. On-site Smart Operation and Maintenance System for Substation Equipment Based on Mobile Network

    Directory of Open Access Journals (Sweden)

    Lin Cheng

    2018-03-01

    Full Text Available The maintenance of substations is crucial for the safety of the electrical grid and power industry. However, for long time, the maintenance teams in the field and the experts in the power companies are divided. The data and expertise exchanges between the on-site maintenance teams and data center are delayed due to the lack of effective communication. This paper introduces an on-site smart operation maintenance system for substation equipment based on mobile network. It is able to establish real-time communication and data exchange channels between the maintenance teams and data center. It consists of an operation and maintenance system platform located on the data center side and smart operation and maintenance boxes with mobile APP which are carried to the field side by the maintenance teams. As the kernel of the system, the smart boxes are bridges between the data center and operation sites. On one hand, it is able to formally upload data to the data center in real-time. One the other hand, the operation and maintenance personnel are able to call for help from the resource on the data center anytime. Using the system proposed in the paper, both efficiency of the operation and maintenance and the normalization of the data can be improved.

  4. Research of nuclear power plant in-service maintenance based on virtual reality

    International Nuclear Information System (INIS)

    Wang Yong; Kuang Weijun

    2015-01-01

    This paper presents a method of constructing nuclear power plant in-service maintenance virtual simulation scene and virtual maintenance process. Taking air baffles dismantling process of CAP1400(China Advanced Passive 1400) nuclear power plant as an instance, this paper discusses ergonomics, space analysis, time assessment based on virtual reality in the process of in-service maintenance. It demonstrates the advantage of using VR technology to design and verify in-service maintenance process of nuclear power plant compared to the conventional way. (author)

  5. Design and evaluation of augmented reality for nuclear power plant maintenance based on Cognitive activity analysis

    International Nuclear Information System (INIS)

    Koo, Jwa Jin

    2008-02-01

    The goals of maintenance in nuclear power plants (NPPs) are to reduce the number of plant shutdowns, to decrease the shutdown time, to minimize the maintenance costs, and to improve nuclear safety. Furthermore, it is difficult for maintenance personnel to conduct work in NPPs due to the complexity of NPPs, safety issues and time constraints. Human errors should be prevented to achieve maintenance goals in NPPs. Therefore, it is necessary to improve working conditions by introducing support systems. Augmented Reality (AR) has the potential to assist with maintenance tasks and make maintenance personnel concentrate on the tasks, which will then the reduced human error and improve human performance. The working procedure for AR systems was designed based on the characteristics of cognitive activity, and an experiment was conducted to estimate the effectiveness of AR. The results indicated that a well-designed working procedure for AR systems was more effective than a conventional paper-based working procedure. In addition, participants made fewer errors using the designed working procedure. AR systems as maintenance support systems are beneficial technology that can improve maintenance performance by reducing cognitive loads and unnecessary movements. An AR application can be attractive and effective at supporting maintenance task

  6. The Issues of Track Maintenance Management in Indonesia (Based on Study of the British Railways

    Directory of Open Access Journals (Sweden)

    Tetria Yunik Dewi Pamungkas

    2017-01-01

    Full Text Available It is believed that there is merit in researching how the management of track maintenance is organized in the United Kingdom, in particular by Network Rail, and then evaluating how this can be applied to the benefit of Indonesian Railways. The purpose of this research was expected to provide recommendations for management improvement of track maintenance by researching the track maintenance management system in Network Rail. This research study is based on secondary data. The analysis was conducted by using comparison method which compares the British Railways management and Indonesia railway management related to track maintenance management. The track maintenance management system was studied by using Network Rail. The results were compared with track maintenance management system in Indonesia. The comparison will provide the data differences that evaluated so the problem can be identified. The final result of this analysis was the identification of problems and improvisation that can be done for the development of track maintenance management in Indonesia. Several management issues have been mapped to several groups: finance management, structure organization, and asset management. From the problems that have been mapped, some improvements are recommended as monopolist authority restriction, maintenance system contract extension, re-structuring organization hierarchy, business plan consideration, track monitoring strategy arrangement, and condition based maintenance strategy adoption.

  7. 14 CFR 119.47 - Maintaining a principal base of operations, main operations base, and main maintenance base...

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 3 2010-01-01 2010-01-01 false Maintaining a principal base of operations, main operations base, and main maintenance base; change of address. 119.47 Section 119.47 Aeronautics... Under Part 121 or Part 135 of This Chapter § 119.47 Maintaining a principal base of operations, main...

  8. Sensitivity of Risk-Based Maintenance Planning of Offshore Wind Turbine Farms

    DEFF Research Database (Denmark)

    Ambühl, Simon; Sørensen, John Dalsgaard

    2017-01-01

    -based) maintenance strategies are implemented. The considered case study focuses on a wind farm consisting of ten 6 MW turbines placed 30 km off the Danish North Sea coast. The results show that the weather forecast is the uncertainty source dominating the maintenance expenses increase when considering risk...

  9. Optimal, Risk-based Operation and Maintenance Planning for Offshore Wind Turbines

    DEFF Research Database (Denmark)

    Sørensen, John Dalsgaard

    2008-01-01

    , corrosion, wear and erosion are associated with significant uncertainty. Observations of the degree of damage can increase the reliability of predictions, especially in connection with condition-based maintenance. The approach can be used for gearboxes, generators, cracks, corrosion, etc. The paper also......For offshore wind turbines costs to operation and maintenance are substantial. This paper describes a risk-based life-cycle approach for optimal planning of operation and maintenance. The approach is based on pre-posterior Bayesian decision theory. Deterioration mechanisms such as fatigue...

  10. Decommissioning and Dismantling of the Floating Maintenance Base 'Lepse' - 13316

    International Nuclear Information System (INIS)

    Field, D.; Mizen, K.

    2013-01-01

    The Lepse was built in Russia in 1934 and commissioned as a dry cargo ship. In 1961 she was re-equipped for use as a nuclear service ship (NSS), specifically a floating maintenance base (FMB), to support the operation of the civilian nuclear fleet (ice-breakers) of the USSR. In 1988 Lepse was taken out of service and in 1990 she was re-classified as a 'berth connected ship', located at a berth near the port of Murmansk under the ownership of Federal State Unitary Enterprise (FSUE) Atomflot. Lepse has special storage facilities for spent nuclear fuel assemblies (SFA) that have been used to store several hundred SFAs for nearly 40 years. High and intermediate-level liquid radioactive waste (LRW) is also present in the spent nuclear fuel assembly storage channels, in special tanks and also in the SFA cooling circuit. Many of the SFAs stored in Lepse are classified as damaged and cannot be removed using standard procedures. The removal of the SFA and LRW from the Lepse storage facilities is a hazardous task and requires specially designed tools, equipment and an infrastructure in which these can be deployed safely. Lepse is a significant environmental hazard in the North West of Russia. Storing spent nuclear fuel and high-level liquid radioactive waste on board Lepse in the current conditions is not acceptable with respect to Russian Federation health, safety and environmental standards and with international best practice. The approved concept design for the removal of the SFA and LRW and dismantling of Lepse requires that the ship be transported to Nerpa shipyard where specialist infrastructure will be constructed and equipment installed. One of the main complexities of the Project lies within the number of interested stakeholders involved in the Project. The Lepse project has been high focus on the international stage for many years with previous international efforts failing to make significant progress towards the objective of decommissioning Lepse. The Northern

  11. The virtual maintenance system: a computer-based support tool for robust design, product monitoring, fault diagnosis and maintenance planning

    NARCIS (Netherlands)

    van Houten, Frederikus J.A.M.; Kimura, F.

    2000-01-01

    Digital (geometric) product models can be used for maintainability analysis and maintenance planning. It is not feasible to build digital product models for maintenance purposes only, but if a digital product model is available, it may be used to support many maintenance-related engineering tasks.

  12. Open system architecture for condition based maintenance applied to a hydroelectric power plant

    Energy Technology Data Exchange (ETDEWEB)

    Amaya, E.J.; Alvares, A.J. [University of Brasilia (UnB), DF (Brazil). Mechanical and Mechatronic Dept.], Emails: eamaya@unb.br, alvares@AlvaresTech.com; Gudwin, R.R. [State University of Campinas (UNICAMP), SP (Brazil). Computer Engineering and Industrial Automation Dept.], E-mail: gudwin@dca.fee.unicamp.br

    2009-07-01

    The hydroelectric power plant of Balbina is implementing a condition based maintenance system applying an open, modular and scalable integrated architecture to provide comprehensive solutions and support to the end users like operational and maintenance team. The system called SIMPREBAL (Predictive Maintenance System of Balbina) is advocate of open standards, in particular through collaborative research programmers. In the developing is clearly understands the need for both, industry standards and a simple to use software development tool chain, supporting the development of complex condition based maintenance systems with multiple partners. The Open System Architecture for Condition Based Maintenance (OSA-CBM) is a standard that consider seven hierarchic layers that represent a logic transition or performed data flow from the data acquisition layer, through the intermediates layers as signal processing, condition monitor, health assessment, prognostics and decision support, to arrive to the presentation layer. SIMPREBAL is being implementing as an OSA-CBM software framework and tool set that allows the creation of truly integrated, comprehensive maintenance solutions through the internet. This paper identifies specific benefits of the application of the OSA-CBM in comprehensive solutions of condition based maintenance for a hydroelectric power plant. (author)

  13. Knowledge-based machine indexing from natural language text: Knowledge base design, development, and maintenance

    Science.gov (United States)

    Genuardi, Michael T.

    1993-01-01

    One strategy for machine-aided indexing (MAI) is to provide a concept-level analysis of the textual elements of documents or document abstracts. In such systems, natural-language phrases are analyzed in order to identify and classify concepts related to a particular subject domain. The overall performance of these MAI systems is largely dependent on the quality and comprehensiveness of their knowledge bases. These knowledge bases function to (1) define the relations between a controlled indexing vocabulary and natural language expressions; (2) provide a simple mechanism for disambiguation and the determination of relevancy; and (3) allow the extension of concept-hierarchical structure to all elements of the knowledge file. After a brief description of the NASA Machine-Aided Indexing system, concerns related to the development and maintenance of MAI knowledge bases are discussed. Particular emphasis is given to statistically-based text analysis tools designed to aid the knowledge base developer. One such tool, the Knowledge Base Building (KBB) program, presents the domain expert with a well-filtered list of synonyms and conceptually-related phrases for each thesaurus concept. Another tool, the Knowledge Base Maintenance (KBM) program, functions to identify areas of the knowledge base affected by changes in the conceptual domain (for example, the addition of a new thesaurus term). An alternate use of the KBM as an aid in thesaurus construction is also discussed.

  14. 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

  15. Developing mobile- and BIM-based integrated visual facility maintenance management system.

    Science.gov (United States)

    Lin, Yu-Cheng; Su, Yu-Chih

    2013-01-01

    Facility maintenance management (FMM) has become an important topic for research on the operation phase of the construction life cycle. Managing FMM effectively is extremely difficult owing to various factors and environments. One of the difficulties is the performance of 2D graphics when depicting maintenance service. Building information modeling (BIM) uses precise geometry and relevant data to support the maintenance service of facilities depicted in 3D object-oriented CAD. This paper proposes a new and practical methodology with application to FMM using BIM technology. Using BIM technology, this study proposes a BIM-based facility maintenance management (BIMFMM) system for maintenance staff in the operation and maintenance phase. The BIMFMM system is then applied in selected case study of a commercial building project in Taiwan to verify the proposed methodology and demonstrate its effectiveness in FMM practice. Using the BIMFMM system, maintenance staff can access and review 3D BIM models for updating related maintenance records in a digital format. Moreover, this study presents a generic system architecture and its implementation. The combined results demonstrate that a BIMFMM-like system can be an effective visual FMM tool.

  16. Developing Mobile- and BIM-Based Integrated Visual Facility Maintenance Management System

    Science.gov (United States)

    Su, Yu-Chih

    2013-01-01

    Facility maintenance management (FMM) has become an important topic for research on the operation phase of the construction life cycle. Managing FMM effectively is extremely difficult owing to various factors and environments. One of the difficulties is the performance of 2D graphics when depicting maintenance service. Building information modeling (BIM) uses precise geometry and relevant data to support the maintenance service of facilities depicted in 3D object-oriented CAD. This paper proposes a new and practical methodology with application to FMM using BIM technology. Using BIM technology, this study proposes a BIM-based facility maintenance management (BIMFMM) system for maintenance staff in the operation and maintenance phase. The BIMFMM system is then applied in selected case study of a commercial building project in Taiwan to verify the proposed methodology and demonstrate its effectiveness in FMM practice. Using the BIMFMM system, maintenance staff can access and review 3D BIM models for updating related maintenance records in a digital format. Moreover, this study presents a generic system architecture and its implementation. The combined results demonstrate that a BIMFMM-like system can be an effective visual FMM tool. PMID:24227995

  17. Developing Mobile- and BIM-Based Integrated Visual Facility Maintenance Management System

    Directory of Open Access Journals (Sweden)

    Yu-Cheng Lin

    2013-01-01

    Full Text Available Facility maintenance management (FMM has become an important topic for research on the operation phase of the construction life cycle. Managing FMM effectively is extremely difficult owing to various factors and environments. One of the difficulties is the performance of 2D graphics when depicting maintenance service. Building information modeling (BIM uses precise geometry and relevant data to support the maintenance service of facilities depicted in 3D object-oriented CAD. This paper proposes a new and practical methodology with application to FMM using BIM technology. Using BIM technology, this study proposes a BIM-based facility maintenance management (BIMFMM system for maintenance staff in the operation and maintenance phase. The BIMFMM system is then applied in selected case study of a commercial building project in Taiwan to verify the proposed methodology and demonstrate its effectiveness in FMM practice. Using the BIMFMM system, maintenance staff can access and review 3D BIM models for updating related maintenance records in a digital format. Moreover, this study presents a generic system architecture and its implementation. The combined results demonstrate that a BIMFMM-like system can be an effective visual FMM tool.

  18. Tablet-based interventions for individuals with ASD: Evidence of generalization and maintenance effects.

    Science.gov (United States)

    Hong, Ee Rea; Kawaminami, Sawako; Neely, Leslie; Morin, Kristi; Davis, John L; Gong, Li-Yuan

    2018-02-05

    Despite positive effects of and established empirical evidence for tablet-based interventions for individuals with autism spectrum disorder (ASD), it is not known whether such findings can be applicable to maintenance and generalization effects of those interventions. This systematic review evaluated peer-reviewed single-case experimental design (SCED) studies concerning evidence of generalization and maintenance effects of tablet-based interventions for individuals with ASD. To evaluate the methodological rigor of the literature in terms of generalization and maintenance effects, the authors adopted four of the basic design standards developed by What Works Clearinghouse (WWC; Kratochwill et al., 2010/2014). In addition, the authors used Tau-U effect size measure and attempted to calculate effect sizes differentiated by the type of generalization and maintenance teaching strategies. A total of 21 studies assessed generalization and/or maintenance effects. In the first evaluation of evidence of generalization and maintenance effects, it was found that more than half of the studies included in this review collected interobserver agreement (IOA) on at least 20% of sessions across all generalization and maintenance conditions and met the minimum quality thresholds of IOA. Meanwhile, less than one third of the studies included more than three data points in each generalization and maintenance condition. With regard to maintenance of effects, about half of the reviewed studies did not report the latency to the maintenance measure, which may hamper the assessment of the clinical and practical significance of the effect of the tablet-based intervention. In the second evaluation, the omnibus Tau-U effect size for baseline to generalization comparisons resulted in a moderate effect. For the contrasts between intervention and generalization comparisons resulted in a small effect. The omnibus Tau-U effect size for baseline and maintenance comparisons resulted in a strong

  19. Maintenance of Process Control Algorithms based on Dynamic Program Slicing

    DEFF Research Database (Denmark)

    Hansen, Ole Fink; Andersen, Nils Axel; Ravn, Ole

    2010-01-01

    Today’s industrial control systems gradually lose performance after installation and must be regularly maintained by means of adjusting parameters and modifying the control algorithm, in order to regain high performance. Industrial control algorithms are complex software systems, and it is partic...... modifying the existing control algorithm, which makes the solution well suited for industrial applications.......Today’s industrial control systems gradually lose performance after installation and must be regularly maintained by means of adjusting parameters and modifying the control algorithm, in order to regain high performance. Industrial control algorithms are complex software systems......, and it is particularly difficult to locate causes of performance loss, while readjusting the algorithm once the cause of performance loss is actually realized and found is relatively simple. In this paper we present a software-engineering approach to the maintenance problem, which provides tools for exploring...

  20. Addressing imperfect maintenance modelling uncertainty in unavailability and cost based optimization

    International Nuclear Information System (INIS)

    Sanchez, Ana; Carlos, Sofia; Martorell, Sebastian; Villanueva, Jose F.

    2009-01-01

    Optimization of testing and maintenance activities performed in the different systems of a complex industrial plant is of great interest as the plant availability and economy strongly depend on the maintenance activities planned. Traditionally, two types of models, i.e. deterministic and probabilistic, have been considered to simulate the impact of testing and maintenance activities on equipment unavailability and the cost involved. Both models present uncertainties that are often categorized as either aleatory or epistemic uncertainties. The second group applies when there is limited knowledge on the proper model to represent a problem, and/or the values associated to the model parameters, so the results of the calculation performed with them incorporate uncertainty. This paper addresses the problem of testing and maintenance optimization based on unavailability and cost criteria and considering epistemic uncertainty in the imperfect maintenance modelling. It is framed as a multiple criteria decision making problem where unavailability and cost act as uncertain and conflicting decision criteria. A tolerance interval based approach is used to address uncertainty with regard to effectiveness parameter and imperfect maintenance model embedded within a multiple-objective genetic algorithm. A case of application for a stand-by safety related system of a nuclear power plant is presented. The results obtained in this application show the importance of considering uncertainties in the modelling of imperfect maintenance, as the optimal solutions found are associated with a large uncertainty that influences the final decision making depending on, for example, if the decision maker is risk averse or risk neutral

  1. Addressing imperfect maintenance modelling uncertainty in unavailability and cost based optimization

    Energy Technology Data Exchange (ETDEWEB)

    Sanchez, Ana [Department of Statistics and Operational Research, Polytechnic University of Valencia, Camino de Vera, s/n, 46071 Valencia (Spain); Carlos, Sofia [Department of Chemical and Nuclear Engineering, Polytechnic University of Valencia, Camino de Vera, s/n, 46071 Valencia (Spain); Martorell, Sebastian [Department of Chemical and Nuclear Engineering, Polytechnic University of Valencia, Camino de Vera, s/n, 46071 Valencia (Spain)], E-mail: smartore@iqn.upv.es; Villanueva, Jose F. [Department of Chemical and Nuclear Engineering, Polytechnic University of Valencia, Camino de Vera, s/n, 46071 Valencia (Spain)

    2009-01-15

    Optimization of testing and maintenance activities performed in the different systems of a complex industrial plant is of great interest as the plant availability and economy strongly depend on the maintenance activities planned. Traditionally, two types of models, i.e. deterministic and probabilistic, have been considered to simulate the impact of testing and maintenance activities on equipment unavailability and the cost involved. Both models present uncertainties that are often categorized as either aleatory or epistemic uncertainties. The second group applies when there is limited knowledge on the proper model to represent a problem, and/or the values associated to the model parameters, so the results of the calculation performed with them incorporate uncertainty. This paper addresses the problem of testing and maintenance optimization based on unavailability and cost criteria and considering epistemic uncertainty in the imperfect maintenance modelling. It is framed as a multiple criteria decision making problem where unavailability and cost act as uncertain and conflicting decision criteria. A tolerance interval based approach is used to address uncertainty with regard to effectiveness parameter and imperfect maintenance model embedded within a multiple-objective genetic algorithm. A case of application for a stand-by safety related system of a nuclear power plant is presented. The results obtained in this application show the importance of considering uncertainties in the modelling of imperfect maintenance, as the optimal solutions found are associated with a large uncertainty that influences the final decision making depending on, for example, if the decision maker is risk averse or risk neutral.

  2. 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)

  3. Bayesian Based Diagnostic Model for Condition Based Maintenance of Offshore Wind Farms

    Directory of Open Access Journals (Sweden)

    Masoud Asgarpour

    2018-01-01

    Full Text Available Operation and maintenance costs are a major contributor to the Levelized Cost of Energy for electricity produced by offshore wind and can be significantly reduced if existing corrective actions are performed as efficiently as possible and if future corrective actions are avoided by performing sufficient preventive actions. This paper presents an applied and generic diagnostic model for fault detection and condition based maintenance of offshore wind components. The diagnostic model is based on two probabilistic matrices; first, a confidence matrix, representing the probability of detection using each fault detection method, and second, a diagnosis matrix, representing the individual outcome of each fault detection method. Once the confidence and diagnosis matrices of a component are defined, the individual diagnoses of each fault detection method are combined into a final verdict on the fault state of that component. Furthermore, this paper introduces a Bayesian updating model based on observations collected by inspections to decrease the uncertainty of initial confidence matrix. The framework and implementation of the presented diagnostic model are further explained within a case study for a wind turbine component based on vibration, temperature, and oil particle fault detection methods. The last part of the paper will have a discussion of the case study results and present conclusions.

  4. Operational optimization of networks of compressors considering condition-based maintenance

    OpenAIRE

    Xenos, DP; Kopanos, GM; Cicciotti, M; Thornhill, NF

    2015-01-01

    The paper presents a mixed integer linear programming model which deals with the optimal operation and maintenance of networks of compressors of chemical plants. This optimization model considers condition-based maintenance which involves the degradation of the condition of the compressors. The paper focuses on online and offline washing, two different cleaning procedures which reduce the extra power used by the compressors due to fouling. The state-of-the-art has demonstrated the optimal sch...

  5. Modeling of Engine Parameters for Condition-Based Maintenance of the MTU Series 2000 Diesel Engine

    Science.gov (United States)

    2016-09-01

    temperature and combined B exhaust temperature. Combined A exhaust temperature measures exhaust gas temperature of cylinders located on the left side of the...engine, and combined B exhaust temperature measures exhaust gas temperature of cylinders on the right side of the engine. For our analysis, the...exhaust gas temperature. 59 V. CONCLUSION AND FUTURE WORK Condition-based maintenance (CBM) is a preventive maintenance method that predicts the onset

  6. An open-source automated continuous condition-based maintenance platform for commercial buildings

    Energy Technology Data Exchange (ETDEWEB)

    Katipamula, Srinivas; Gowri, Krishnan; Hernandez, George

    2016-09-09

    This paper describes one such reference process that can be deployed to provide continuous automated conditioned-based maintenance management for buildings that have BIM, a building automation system (BAS) and a computerized maintenance management software (CMMS) systems. The process can be deployed using an open source transactional network platform, VOLTTRON™, designed for distributed sensing and controls and supports both energy efficiency and grid services.

  7. Development of a knowledge-based information management system for plant maintenance

    International Nuclear Information System (INIS)

    Yim, Hyung Sang; Park, Young Jae; Lee, Sang Min; Choi, Jae Boong; Kim, Young Jin; Roh, Eun Chul; Lee, Byung Ine

    2003-01-01

    Recently, the importance of Plant Maintenance(PM) was highly raised to provide efficient plant operation which highly affects the productivity. For this reason, a number of engineering methodologies, such as Risk-Based Inspection(RBI), Fitness For Service guidelines(FFS), Plant Lifecycle Management(PLM), have been applied to improve the plant operation efficiency. Also, a network-based business operation system, which is called ERP(Enterprise Resource Planning), has been introduced in the field of plant maintenance. However, there was no attempt to connect engineering methodologies to the ERP PM system. In this paper, a knowledge-based information system for the plant operation of steel making company has been proposed. This system, which is named as K-VRS(Knowledge-based Virtual Reality System), provides a connection between ERP plant maintenance module and knowledge-based engineering methodologies, and thus, enables network-based highly effective plant maintenance process. The developed system is expected to play a great role for more efficient and safer plant maintenance

  8. Development of a knowledge-based information management system for plant maintenance

    Energy Technology Data Exchange (ETDEWEB)

    Yim, Hyung Sang; Park, Young Jae; Lee, Sang Min; Choi, Jae Boong; Kim, Young Jin [Sungkyunkwan Univ., Seoul (Korea, Republic of); Roh, Eun Chul; Lee, Byung Ine [Pohang Iron and Steel Company, Pohang (Korea, Republic of)

    2003-07-01

    Recently, the importance of Plant Maintenance(PM) was highly raised to provide efficient plant operation which highly affects the productivity. For this reason, a number of engineering methodologies, such as Risk-Based Inspection(RBI), Fitness For Service guidelines(FFS), Plant Lifecycle Management(PLM), have been applied to improve the plant operation efficiency. Also, a network-based business operation system, which is called ERP(Enterprise Resource Planning), has been introduced in the field of plant maintenance. However, there was no attempt to connect engineering methodologies to the ERP PM system. In this paper, a knowledge-based information system for the plant operation of steel making company has been proposed. This system, which is named as K-VRS(Knowledge-based Virtual Reality System), provides a connection between ERP plant maintenance module and knowledge-based engineering methodologies, and thus, enables network-based highly effective plant maintenance process. The developed system is expected to play a great role for more efficient and safer plant maintenance.

  9. Research on gesture recognition of augmented reality maintenance guiding system based on improved SVM

    Science.gov (United States)

    Zhao, Shouwei; Zhang, Yong; Zhou, Bin; Ma, Dongxi

    2014-09-01

    Interaction is one of the key techniques of augmented reality (AR) maintenance guiding system. Because of the complexity of the maintenance guiding system's image background and the high dimensionality of gesture characteristics, the whole process of gesture recognition can be divided into three stages which are gesture segmentation, gesture characteristic feature modeling and trick recognition. In segmentation stage, for solving the misrecognition of skin-like region, a segmentation algorithm combing background mode and skin color to preclude some skin-like regions is adopted. In gesture characteristic feature modeling of image attributes stage, plenty of characteristic features are analyzed and acquired, such as structure characteristics, Hu invariant moments features and Fourier descriptor. In trick recognition stage, a classifier based on Support Vector Machine (SVM) is introduced into the augmented reality maintenance guiding process. SVM is a novel learning method based on statistical learning theory, processing academic foundation and excellent learning ability, having a lot of issues in machine learning area and special advantages in dealing with small samples, non-linear pattern recognition at high dimension. The gesture recognition of augmented reality maintenance guiding system is realized by SVM after the granulation of all the characteristic features. The experimental results of the simulation of number gesture recognition and its application in augmented reality maintenance guiding system show that the real-time performance and robustness of gesture recognition of AR maintenance guiding system can be greatly enhanced by improved SVM.

  10. 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

  11. Routine maintenance: safety term based work selection; Selecao de trabalho baseado no prazo seguro

    Energy Technology Data Exchange (ETDEWEB)

    Camargo, Albair de; Filho, Antnio S.; Brendler, Fabiano E.; Adamatti, Gilberto A.; Naruto, Itiro; Araujo, Luiz C.F.; Puerari, Roberto [PETROBRAS, Rio de Janeiro, RJ (Brazil)

    2004-07-01

    This work has objective to present the experience of improvement of routine maintenance system in some refineries of the PETROBRAS system, with the purpose to increase the efficiency in the Industrial Maintenance Management (cost), Utilization and HSE (Health, Safety and Environment), key of success of a petroleum company. The new system is based on the implantation of the culture of work selection in the safe period, through elaboration of new maintenance procedure, with emphasis in decisions shared between Operation and Maintenance Team, resulting in reduction of emergencies, making possible contract of services of maintenance for packages and improved allocation of resources. This work treat about improvement of the system in use, in view of that it has already taken in consideration the consequence of fail in the maintenance with participation of the operators. Besides of these challenge, this modification was made without causing riots in the process of implantation of SAP. As main result, financial profits had got better of resources with increase of safety, considering that they are analyzed in a way it that systematized potential risks. (author)

  12. Statistical Learning Framework with Adaptive Retraining for Condition-Based Maintenance

    Energy Technology Data Exchange (ETDEWEB)

    An, Sang Ha; Chang, Soon Heung [Korea Advanced Institute of Science and Technology, Daejeon (Korea, Republic of); Heo, Gyun Young [Kyung Hee University, Yongin (Korea, Republic of); Seo, Ho Joon; Kim, Su Young [BNF Technology Inc., Daejeon (Korea, Republic of)

    2009-05-15

    As systems become more complex and more critical in our daily lives, the need for the maintenance based on the reliable monitoring and diagnosis has become more apparent. However, in reality, the general opinion has been that 'maintenance is a necessary evil' or 'nothing can be done to improve maintenance costs'. Perhaps these were true statements twenty years ago when many of the diagnostic technologies were not fully developed. The developments of microprocessor or computer based instrumentation that can be used to monitor the operating condition of plant equipment, machinery and systems have provided the means to manage the maintenance operation. They have provided the means to reduce or eliminate unnecessary repairs, prevent catastrophic machine failures and reduce the negative impact of the maintenance operation on the profitability of manufacturing and production plants. Condition-based maintenance (CBM) techniques help determine the condition of in-service equipment in order to predict when maintenance should be performed. Most of the statistical learning techniques are only valid as long as the physics of a system does not change. If any significant change such as the replacement of a component or equipment occurs in the system, the statistical learning model should be re-trained or re-developed to adapt the new system. In this research, authors will propose a statistical learning framework which can be applicable for various CBMs, and the concept of the adaptive retraining technique will be described to support the execution of the framework so that the monitoring system does not need to be re-developed or re-trained even though there are any significant changes in the system or component.

  13. A risk-based model for maintenance decision support of civil structures using RAMS

    NARCIS (Netherlands)

    Viana Da Rocha, T. C.; Stipanovic, I.; Hartmann, A.; Bakker, J.

    2017-01-01

    As a cornerstone of transportation asset management, risk-based approaches have been used to support maintenance decisions of civil structures. However, ambiguous and subjective risk criteria and inconsistency on the use of risk-based approaches can lead to a fuzzy understanding of the risks

  14. 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...

  15. Target-Based Maintenance of Privacy Preserving Association Rules

    Science.gov (United States)

    Ahluwalia, Madhu V.

    2011-01-01

    In the context of association rule mining, the state-of-the-art in privacy preserving data mining provides solutions for categorical and Boolean association rules but not for quantitative association rules. This research fills this gap by describing a method based on discrete wavelet transform (DWT) to protect input data privacy while preserving…

  16. A preventive maintenance policy based on dependent two-stage deterioration and external shocks

    International Nuclear Information System (INIS)

    Yang, Li; Ma, Xiaobing; Peng, Rui; Zhai, Qingqing; Zhao, Yu

    2017-01-01

    This paper proposes a preventive maintenance policy for a single-unit system whose failure has two competing and dependent causes, i.e., internal deterioration and sudden shocks. The internal failure process is divided into two stages, i.e. normal and defective. Shocks arrive according to a non-homogeneous Poisson process (NHPP), leading to the failure of the system immediately. The occurrence rate of a shock is affected by the state of the system. Both an age-based replacement and finite number of periodic inspections are schemed simultaneously to deal with the competing failures. The objective of this study is to determine the optimal preventive replacement interval, inspection interval and number of inspections such that the expected cost per unit time is minimized. A case study on oil pipeline maintenance is presented to illustrate the maintenance policy. - Highlights: • A maintenance model based on two-stage deterioration and sudden shocks is developed. • The impact of internal system state on external shock process is studied. • A new preventive maintenance strategy combining age-based replacements and periodic inspections is proposed. • Postponed replacement of a defective system is provided by restricting the number of inspections.

  17. Bayesian based Prognostic Model for Predictive Maintenance of Offshore Wind Farms

    DEFF Research Database (Denmark)

    Asgarpour, Masoud; Sørensen, John Dalsgaard

    2018-01-01

    monitoring, fault prediction and predictive maintenance of offshore wind components is defined. The diagnostic model defined in this paper is based on degradation, remaining useful lifetime and hybrid inspection threshold models. The defined degradation model is based on an exponential distribution......The operation and maintenance costs of offshore wind farms can be significantly reduced if existing corrective actions are performed as efficient as possible and if future corrective actions are avoided by performing sufficient preventive actions. In this paper a prognostic model for degradation...

  18. Bayesian based Prognostic Model for Predictive Maintenance of Offshore Wind Farms

    DEFF Research Database (Denmark)

    Asgarpour, Masoud

    2017-01-01

    monitoring, fault detection and predictive maintenance of offshore wind components is defined. The diagnostic model defined in this paper is based on degradation, remaining useful lifetime and hybrid inspection threshold models. The defined degradation model is based on an exponential distribution......The operation and maintenance costs of offshore wind farms can be significantly reduced if existing corrective actions are performed as efficient as possible and if future corrective actions are avoided by performing sufficient preventive actions. In this paper a prognostic model for degradation...

  19. Maintenance based design and equipment reliability for AECL's advanced CANDU reactor

    International Nuclear Information System (INIS)

    Meraw, D.

    2008-01-01

    This paper will describe how the elements of AECL's Maintenance Based Design will enable the Advanced CANDU Reactor to sustain high equipment reliability and capacity factors over the 60-year design life of the plant. The elements of Maintenance Based Design are; 1-Design Reliable Systems,Structures and Components (SSCs); 2-Select and Procure Reliable Components; 3-Incorporate Monitoring Capabilities and Facilities for SSCs; 4-Develop Maintenance Strategies and Programs for SSCs; 5-Apply Lessons Learned From Previous Plants; 6-Incorporate Maintainability and Event Free Features in the Design; 7-Provide Enhanced Maintenance Management Information and Tools to the Customer; 8-Optimize Chemistry and Materials in the Design. All these elements will be discussed with a detailed focus on the following; Design Reliable SSCs Using the techniques outlined in INPO AP-913, Equipment Reliability Process Description, each CANDU system that has caused any station past unavailability is analyzed as part of the ACR design in order to identify the critical components and any Single Points of Vulnerability (SPVs). All SPVs are then analyzed further in order to determine if they can be practically designed out or otherwise mitigated by the design. Developing Maintenance Strategies and Programs for SSCs Equipment degradation begins as soon as a component is manufactured and accelerates during initial commissioning and eventual operation. In order to sustain high levels of equipment reliability a maintenance strategy must be developed during the design phase and be ready for implementation before the start of commissioning. This maintenance strategy is developed for all critical components using the techniques of INPO AP-913 and other best industry practices. The strategy can be expanded and customized in conjunction with a future owner. Specific examples from the current ACR-1000 design will be used to show how these elements are being implemented.

  20. Maintenance and Drainage Guidance for the Scott Base Transition, Antarctica

    Science.gov (United States)

    2014-10-01

    albedo and quickens the melt. Several strategies reduce the amount of dirt tracked on- to the ice shelf: 1. Any vehicles using the ice shelf should...the Ice Transition segment of the SBT is to keep the snow albedo high (keep snow white). This reduces roadway and road-base disin- tegration (i.e...closest to the cliff was 38 ft (11.6 m) deep, and all but the furthest seaward hole encountered sediment (presumably the sea floor or the under- ice

  1. Integrated vibration-based maintenance: an approach for continuous reduction in LCC. A case study

    Energy Technology Data Exchange (ETDEWEB)

    Najjar, B. [ER Konsult Utveckling AB, Vaexjoe (Sweden)

    1998-12-31

    The biggest thread in achieving and maintaining high equipment effectiveness can be stated as: whether the improved manufacturing processes capable of producing quality products at a competitive cost. The effect of a new vibration-based maintenance concept, called Total Quality Maintenance (TQMain), is introduced. It aims to make intensive use of the real-time data acquisition and analysis to detect causes behind product quality deviation and failures in machinery, and following defect development at an early stage to increase machine mean effective life and improve company`s economics. The effect of TQMain on LCC of machinery and company`s economics is discussed. A case study to reveal savings in maintenance cost when a vibration-based policy involved, is presented. Using TQMain, company`s economics can be improved effectively through continuous improvement of the technical and economic effectiveness of production processes. (orig.) 14 refs.

  2. An end-to-end communications architecture for condition-based maintenance applications

    Science.gov (United States)

    Kroculick, Joseph

    2014-06-01

    This paper explores challenges in implementing an end-to-end communications architecture for Condition-Based Maintenance Plus (CBM+) data transmission which aligns with the Army's Network Modernization Strategy. The Army's Network Modernization strategy is based on rolling out network capabilities which connect the smallest unit and Soldier level to enterprise systems. CBM+ is a continuous improvement initiative over the life cycle of a weapon system or equipment to improve the reliability and maintenance effectiveness of Department of Defense (DoD) systems. CBM+ depends on the collection, processing and transport of large volumes of data. An important capability that enables CBM+ is an end-to-end network architecture that enables data to be uploaded from the platform at the tactical level to enterprise data analysis tools. To connect end-to-end maintenance processes in the Army's supply chain, a CBM+ network capability can be developed from available network capabilities.

  3. 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

    electrical and mechanical components as well as a control system also reliability aspects of these components are discussed in the paper. Illustrative examples are presented considering uncertainty modelling, reliability assessment and risk-based planning of Operation & Maintenance....... 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...... & Maintenance of offshore wind turbines. Further, the paper considers models for uncertainty modelling and reliability assessment of structural components such as tower, blades, substructure and foundation as well as cast steel drivetrain components. The function of a wind turbine is highly dependent on many...

  4. 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

  5. Risk-Based Operation and Maintenance Planning for Offshore Wind Turbines

    DEFF Research Database (Denmark)

    Nielsen, Jannie Jessen; Sørensen, John Dalsgaard

    2010-01-01

    Operation and maintenance (O&M) are large contributors to the cost of energy for offshore wind turbines. Optimal planning of O&M should include use of inspections and monitoring results to make decisions that minimize the expected costs through the lifetime of the structures. For offshore...... structures it is especially important because of the dependence on weather windows for inspections and repairs to be possible. A model has been developed to estimate the expected costs to corrective and condition based maintenance for a wind turbine with a single component. The deterioration of the component...

  6. On risk-based operation and maintenance of offshore wind turbine components

    DEFF Research Database (Denmark)

    Nielsen, Jannie Jessen; Sørensen, John Dalsgaard

    2011-01-01

    Operation and maintenance are significant contributors to the cost of energy for offshore wind turbines. Optimal planning could rationally be based on Bayesian pre-posterior decision theory, and all costs through the lifetime of the structures should be included. This paper contains a study...... of a generic case where the costs are evaluated for a single wind turbine with a single component. Costs due to inspections, repairs, and lost production are included in the model. The costs are compared for two distinct maintenance strategies, namely with and without inclusion of periodic imperfect...

  7. Technical requirements on knowledge base and instrumentation system for decision making in plant operation and maintenance

    International Nuclear Information System (INIS)

    Kitamura, Masaharu; Yoshikawa, Shinji; Hasegawa, Makoto

    1998-03-01

    A series of technical surveys and studies are described in this report to examine and identify technical requirements to be posed on knowledge base and instrumentation system as the fundamental in high reliability computational decision making in operation and maintenance of nuclear power plants. Monitoring and diagnosis are focused as the important tasks among the operation/maintenance-related tasks. A concrete monitoring and diagnosis system configuration has been proposed consisting of distributed symptom database and of on-demand measurement subsystem. An prototype of the proposed system configuration has been successfully verified. (author)

  8. A model for determining condition-based maintenance policies for deteriorating multi-component systems

    NARCIS (Netherlands)

    Hontelez, J.A.M.; Wijnmalen, D.J.D.

    1993-01-01

    We discuss a method to determine strategies for preventive maintenance of systems consisting of gradually deteriorating components. A model has been developed to compute not only the range of conditions inducing a repair action, but also inspection moments based on the last known condition value so

  9. The business case for condition-based maintenance: a hybrid (non-) financial approach

    NARCIS (Netherlands)

    Tiddens, W.W.; Tinga, T.; Braaksma, A.J.J.; Brouwer, O.; Cepin, Marko; Bris, Radim

    2017-01-01

    Although developing business cases is key for evaluating project success, the costs and benefits of condition-based maintenance (CBM) implementations are often not explicitly defined and evaluated. Using the design science methodology, we developed a hybrid business case approach to help managers

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

    DEFF Research Database (Denmark)

    Jin, Tongdan; Ding, Yi; Guo, Huairui

    2012-01-01

    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...

  11. Knowledge lost in data : Organizational impediments to condition-based maintenance in the process industry

    NARCIS (Netherlands)

    van de Kerkhof, Roland; Akkermans, Henk; Noorderhaven, Niels; Zijm, H.; Klumpp, M.; Clausen, U.; Ten Hompel, M.

    2016-01-01

    In this chapter we report on a pilot study of Condition-Based Maintenance (CBM) in the process industries, such as the steelmaking- and chemical industries, and propose a diagnostic instrument for systematically analysing the challenges to the successful implementation and execution of a CBM

  12. Automotive Maintenance Data Base for Model Years 1976-1979. Part I

    Science.gov (United States)

    1980-12-01

    An update of the existing data base was developed to include life cycle maintenance costs of representative vehicles for the model years 1976-1979. Repair costs as a function of time are also developed for a passenger car in each of the compact, subc...

  13. Automotive Maintenance Data Base for Model Years 1976-1979. Part II : Appendix E and F

    Science.gov (United States)

    1980-12-01

    An update of the existing data base was developed to include life cycle maintenance costs of representative vehicles for the model years 1976-1979. Repair costs as a function of time are also developed for a passenger car in each of the compact, subc...

  14. A discrete event simulation design for block-based maintenance planning under random machine usage

    NARCIS (Netherlands)

    de Jonge, Bram

    2015-01-01

    Existing research on block-based preventive maintenance planning generally assumes that machines are either used continuously, or that times until failure do not depend on the actual usage of machines. In practice, however, it is often more realistic to assume that machines are not used continuously

  15. Geometric Process-Based Maintenance and Optimization Strategy for the Energy Storage Batteries

    Directory of Open Access Journals (Sweden)

    Yan Li

    2016-01-01

    Full Text Available Renewable energy is critical for improving energy structure and reducing environment pollution. But its strong fluctuation and randomness have a serious effect on the stability of the microgrid without the coordination of the energy storage batteries. The main factors that influence the development of the energy storage system are the lack of valid operation and maintenance management as well as the cost control. By analyzing the typical characteristics of the energy storage batteries in their life cycle, the geometric process-based model including the deteriorating system and the improving system is firstly built for describing the operation process, the preventive maintenance process, and the corrective maintenance process. In addition, this paper proposes an optimized management strategy, which aims to minimize the long-run average cost of the energy storage batteries by defining the time interval of the detection and preventive maintenance process as well as the optimal corrective maintenance times, subjected to the state of health and the reliability conditions. The simulation is taken under the built model by applying the proposed energy storage batteries’ optimized management strategy, which verifies the effectiveness and applicability of the management strategy, denoting its obvious practicality on the current application.

  16. An Enhanced Preventive Maintenance Optimization Model Based on a Three-Stage Failure Process

    Directory of Open Access Journals (Sweden)

    Ruifeng Yang

    2015-01-01

    Full Text Available Nuclear power plants are highly complex systems and the issues related to their safety are of primary importance. Probabilistic safety assessment is regarded as the most widespread methodology for studying the safety of nuclear power plants. As maintenance is one of the most important factors for affecting the reliability and safety, an enhanced preventive maintenance optimization model based on a three-stage failure process is proposed. Preventive maintenance is still a dominant maintenance policy due to its easy implementation. In order to correspond to the three-color scheme commonly used in practice, the lifetime of system before failure is divided into three stages, namely, normal, minor defective, and severe defective stages. When the minor defective stage is identified, two measures are considered for comparison: one is that halving the inspection interval only when the minor defective stage is identified at the first time; the other one is that if only identifying the minor defective stage, the subsequent inspection interval is halved. Maintenance is implemented immediately once the severe defective stage is identified. Minimizing the expected cost per unit time is our objective function to optimize the inspection interval. Finally, a numerical example is presented to illustrate the effectiveness of the proposed models.

  17. Risk-Based, genetic algorithm approach to optimize outage maintenance schedule

    International Nuclear Information System (INIS)

    Hadavi, S. Mohammad Hadi

    2008-01-01

    A huge number of components are typically scheduled for maintenance when a nuclear power plant is shut down for its planned outage. Among these components, a number of them are risk significant so that their operability as well as reliability is of prime concern. Lack of proper maintenance for such components during the outage would impose substantial risk on the nuclear power plant (NPP) operation. In this paper, a new approach based on genetic algorithm (GA) is presented for the optimization of the NPP maintenance schedule during plant outage/overhaul, and an optimizer is developed accordingly. The developed optimizer, coupled with the suggested risk-cost model, compromises the cost in favor of maintaining the risk imposed by each schedule below regulatory/industry set limits. The suggested cost model consists of two elements, one considering the cost incurred by maintenance activities and the other incorporating the loss of revenues if needed, but unscheduled component maintenance causes further plant shutdown. The optimizer is developed in such a way that any risk and/or cost models the user desires can be applied. The performance of the developed GA/optimizer is evaluated by comparing its predictions with Monte Carlo simulation results. It is shown that the GA/optimizer performs significantly better

  18. Determinants of Physical Activity Maintenance in Breast Cancer Survivors After a Community-Based Intervention.

    Science.gov (United States)

    Lee, C Ellen; Von Ah, Diane; Szuck, Beth; Lau, Yiu-Keung James

    2016-01-01

    To determine whether empirically selected and social cognitive theory-based factors, including baseline characteristics and modifiable behavioral and psychosocial factors, were determinants of physical activity (PA) maintenance in breast cancer survivors (BCSs) six months after a PA intervention.
. Single-group longitudinal study.
. The Breast Health Centre in Winnipeg, Manitoba, Canada.
. 42 survivors with stage 0-III breast cancer who completed chemotherapy and/or radiation therapy.
. The community-based PA intervention included six weekly education and practice sessions on home-based aerobic, resistance, balance, and flexibility exercises.
. The dependent variable, PA maintenance, was determined based on PA level measurement at six months postintervention. The independent variables of baseline characteristics (age, stage of cancer, and chronic musculoskeletal symptoms) and modifiable behavioral and psychosocial factors (PA level, fatigue, PA self-efficacy in overcoming barriers and performing tasks) were assessed at baseline and postintervention.
. Multivariate regression analyses revealed that baseline fatigue and chronic musculoskeletal symptoms were the only factors significantly associated with PA maintenance.
. Baseline fatigue level and chronic musculoskeletal symptoms were significant determinants of PA maintenance in breast cancer survivors who had completed a community-based PA intervention. However, other key factors were considered.
. Prior to participation in community-based PA interventions, clinicians should take into account the effects of high baseline fatigue levels and chronic musculoskeletal symptoms on potential PA maintenance, and consider additional assessments and support for BCSs to sustain their PA behavioral change.
.

  19. Concept design of CFETR superconducting magnet system based on different maintenance ports

    International Nuclear Information System (INIS)

    Zheng, Jinxing; Liu, Xufeng; Song, Yuntao; Wan, Yuanxi; Li, Jiangang; Wu, Sontao; Wan, Baonian; Ye, Minyou; Wei, Jianghua; Xu, Weiwei; Liu, Sumei; Weng, Peide; Lu, Kun; Luo, Zhengping

    2013-01-01

    Highlights: • This article discussed the concept design of the magnet system of CFETR based on different maintenance port cases. • The major and minor radius of plasma is 5.7 m and 1.6 m, and the central magnetic field was designed as 4.5/5.0 T. • The different maintenance ports design have little impact on the design of TF and CS coils’ design, but have certain impact on the PF coils’ design. -- Abstract: CFETR which stands for “China Fusion Engineering Test Reactor” is a new tokamak device. Its magnet system includes the Toroidal Field (TF) winding, Center solenoid winding (CS) and Poloidal Field (PF) winding. The main goal of the project is to build a fusion engineering Tokamak reactor with its fusion power is 50–200 MW and should be self-sufficiency by blanket. In order to ensure the maintenance ports design and maintenance method, this article discussed the concept design of the magnet system based on different maintenance port cases. The paper detailed studied the magnet system of CFETR including the electromagnetic analysis and parameters for TF (CS)PF. Besides, the volt-seconds of ohmic field are presented as detailed as possible in this paper. In addition, the calculations and optimizations of equilibrium field which should guarantee the plasma discharge of single null shape is carried out. The design work reported here illustrates that the present maintenance ports will not have a great impact on the design of the magnet system. The concept design of the magnet system can meet the requirement of the physical target

  20. An improved segmentation-based HMM learning method for Condition-based Maintenance

    International Nuclear Information System (INIS)

    Liu, T; Lemeire, J; Cartella, F; Meganck, S

    2012-01-01

    In the domain of condition-based maintenance (CBM), persistence of machine states is a valid assumption. Based on this assumption, we present an improved Hidden Markov Model (HMM) learning algorithm for the assessment of equipment states. By a good estimation of initial parameters, more accurate learning can be achieved than by regular HMM learning methods which start with randomly chosen initial parameters. It is also better in avoiding getting trapped in local maxima. The data is segmented with a change-point analysis method which uses a combination of cumulative sum charts (CUSUM) and bootstrapping techniques. The method determines a confidence level that a state change happens. After the data is segmented, in order to label and combine the segments corresponding to the same states, a clustering technique is used based on a low-pass filter or root mean square (RMS) values of the features. The segments with their labelled hidden state are taken as 'evidence' to estimate the parameters of an HMM. Then, the estimated parameters are served as initial parameters for the traditional Baum-Welch (BW) learning algorithms, which are used to improve the parameters and train the model. Experiments on simulated and real data demonstrate that both performance and convergence speed is improved.

  1. The role of the restructured Mobile Remote Service Base System (MBS) in support of Space Station maintenance and servicing

    Science.gov (United States)

    Darlington, T.; Krukewich, K.

    1992-08-01

    The critical parameters resulting from the restructuring of Space Station Freedom which necessitated the redesign of the Mobile Remote Service Base System (MBS) are described. These include optimization of robotic attachment locations for access to the Space Station truss-mounted orbital replacement units, transport of logistics carriers to the maintenance sites, minimization of EVA overhead associated with maintenance, self-maintenance of other mobile servicing system (MSS) elements on the MBS, and balancing of station EVA and extravehicular robotics in a complementary fashion to minimize maintenance overhead in general. Consideration is given to the configuration of the resulting MBS, which provides the program with maximum flexibility to utilize the assets of the MSS and optimizes end-to-end maintenance with regard to the use of station resources such as crew time and power. Maintenance and servicing scenarios which are instrumental to the reconfigured MBS as well as the results of improved maintenance capability are presented.

  2. Advanced Maintenance Simulation by Means of Hand-Based Haptic Interfaces

    Science.gov (United States)

    Nappi, Michele; Paolino, Luca; Ricciardi, Stefano; Sebillo, Monica; Vitiello, Giuliana

    Aerospace industry has been involved in virtual simulation for design and testing since the birth of virtual reality. Today this industry is showing a growing interest in the development of haptic-based maintenance training applications, which represent the most advanced way to simulate maintenance and repair tasks within a virtual environment by means of a visual-haptic approach. The goal is to allow the trainee to experiment the service procedures not only as a workflow reproduced at a visual level but also in terms of the kinaesthetic feedback involved with the manipulation of tools and components. This study, conducted in collaboration with aerospace industry specialists, is aimed to the development of an immersive virtual capable of immerging the trainees into a virtual environment where mechanics and technicians can perform maintenance simulation or training tasks by directly manipulating 3D virtual models of aircraft parts while perceiving force feedback through the haptic interface. The proposed system is based on ViRstperson, a virtual reality engine under development at the Italian Center for Aerospace Research (CIRA) to support engineering and technical activities such as design-time maintenance procedure validation, and maintenance training. This engine has been extended to support haptic-based interaction, enabling a more complete level of interaction, also in terms of impedance control, and thus fostering the development of haptic knowledge in the user. The user’s “sense of touch” within the immersive virtual environment is simulated through an Immersion CyberForce® hand-based force-feedback device. Preliminary testing of the proposed system seems encouraging.

  3. MOVES: A knowledge-based system for maintenance planning for motor-operated valves

    International Nuclear Information System (INIS)

    Winter, M.

    1987-01-01

    Over the past several years, knowledge-based expert systems have emerged as an important part of the general research area known as artificial intelligence. This paper describes a cooperative effort between faculty members at Iowa State University and engineers at the Duane Arnold Energy Center [a 545-MW(electric) boiling water reactor operated by Iowa Electric Light and Power Company] to explore the development of an advisory system for valve maintenance planning. This knowledge-based program, known as Motor-Operated Valves Expert System (MOVES), has a data base that currently includes safety-related motor-operated valves (∼117 valves). Valve maintenance was selected as the subject for the expert system because of the importance of valves in nuclear plant and their impact of plant availability. MOVES is being developed using the microcomputer-(IBM compatible) based expert system tool INSIGHT2+. The authors have found that the project benefits both the university and the utility

  4. 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.

  5. Analysis of the possibility of applying a condition-based maintenance model on an example of tank weapons

    Directory of Open Access Journals (Sweden)

    Igor J. Epler

    2013-12-01

    Full Text Available For any modern army it is very important to continuously maintain a high degree of operational (combat readiness (availability in order to maximize the effectiveness of the use of technical systems. Since determination and prediction of technical states and failures of technical systems in engineering, especially in armament, are difficult due to the impossibility of continuous condition monitoring with appropriate measuring equipment there is a need for a maintenance model that would be most helpful in taking timely action maintenance. In this paper, the subject of research is a model of maintenance of the M-84 tank  weapoons systems.   IntroductionThe M-84 tank is one of the most promising technical systems in the Serbian Army. Its use and modifications are foreseen in the next ten years. The  M-84 is characterized by good tactical and technical characteristics. It has a powerful 125 mm cannon, coupled 7.62 mm machine gun and 12.7 mm anti-aircraft machine gun. The M-84 tank has an automatic battery charger and a fire control system. The fire control system enables fast target tracking and stabilization of the cannon barrel, which is a prerequisite for timely and favorable effect on the target. There are certain ambiguities in the existing model of maintenance of tank weapons.   Technical diagnostics Technical diagnostics, as a part of the process of condition-based maintenance, should determine technical conditions of components or technical systems with certain accuracy at a point in time.   Maintenance strategy A maintenance strategy can be defined as a variant of a maintenance system determined by a concept, organization and character of maintenance procedures, as well as the relationship between the various levels at which maintenance is performed. It is defined for technical system parts, individual technical systems and for system maintenance as a whole. The basic maintenance strategies implemented today are: -      corrective

  6. Cognitive Artificial Intelligence Method for Interpreting Transformer Condition Based on Maintenance Data

    Directory of Open Access Journals (Sweden)

    Karel Octavianus Bachri

    2017-07-01

    Full Text Available A3S(Arwin-Adang-Aciek-Sembiring is a method of information fusion at a single observation and OMA3S(Observation Multi-time A3S is a method of information fusion for time-series data. This paper proposes OMA3S-based Cognitive Artificial-Intelligence method for interpreting Transformer Condition, which is calculated based on maintenance data from Indonesia National Electric Company (PLN. First, the proposed method is tested using the previously published data, and then followed by implementation on maintenance data. Maintenance data are fused to obtain part condition, and part conditions are fused to obtain transformer condition. Result shows proposed method is valid for DGA fault identification with the average accuracy of 91.1%. The proposed method not only can interpret the major fault, it can also identify the minor fault occurring along with the major fault, allowing early warning feature. Result also shows part conditions can be interpreted using information fusion on maintenance data, and the transformer condition can be interpreted using information fusion on part conditions. The future works on this research is to gather more data, to elaborate more factors to be fused, and to design a cognitive processor that can be used to implement this concept of intelligent instrumentation.

  7. Single-stage Kanban system with deterioration failures and condition-based preventive maintenance

    International Nuclear Information System (INIS)

    Xanthopoulos, A.S.; Koulouriotis, D.E.; Botsaris, P.N.

    2015-01-01

    Despite the fact that the fields of pull type production control policies and condition-based preventive maintenance have much in common contextually, they have evolved independently up to now. In this investigation, an attempt is made to bridge the gap between these two branches of knowledge by introducing the single-stage Kanban system with deterioration failures and condition-based preventive maintenance. The formalism of continuous time Markov chains is used to model the system and expressions for eight performance metrics are derived. Two important, from a managerial perspective, constrained optimization problems for the proposed model are defined where the objective is the simultaneous optimization of the Kanban policy, the preventive maintenance policy and the inspection schedule under conflicting performance criteria. Multiple instances of each optimization problem are solved by means of the augmented Lagrangian genetic algorithm. The results from the optimization trials coupled by the results from extensive numerical examples facilitate the thorough investigation of the system’s behaviour. - Highlights: • Kanban system with deterioration failures and preventive maintenance is introduced. • The system is modeled as a continuous time Markov chain. • Expressions for eight performance metrics are derived. • The behavior of the system is studied through numerical examples. • Optimization results for selected performance metrics are presented

  8. 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

  9. Heuristic hybrid game approach for fleet condition-based maintenance planning

    International Nuclear Information System (INIS)

    Feng, Qiang; Bi, Xiong; Zhao, Xiujie; Chen, Yiran; Sun, Bo

    2017-01-01

    The condition-based maintenance (CBM) method is commonly used to select appropriate maintenance opportunities according to equipment status over a period of time. The CBM of aircraft fleets is a fleet maintenance planning problem. In this problem, mission requirements, resource constraints, and aircraft statuses are considered to find an optimal strategy set. Given that the maintenance strategies for each aircraft are finite, fleet CBM can be treated as a combinatorial optimization problem. In this study, the process of making a decision on the CBM of military fleets is analyzed. The fleet CBM problem is treated as a two-stage dynamic decision-making problem. Aircraft are divided into dispatch and standby sets; thus, the problem scale is significantly reduced. A heuristic hybrid game (HHG) approach comprising a competition game and a cooperative game is proposed on the basis of heuristic rule. In the dispatch set, a competition game approach is proposed to search for a local optimal strategy matrix. A cooperative game method for the two sets is also proposed to ensure global optimization. Finally, a case study regarding a fleet comprising 20 aircraft is conducted, with the results proving that the approach efficiently generates outcomes that meet the mission risk-oriented schedule requirement. - Highlights: • A new heuristic hybrid game method for fleet condition-based maintenance is proposed. • The problem is simplified by hierarchical solving based on dispatch and standby set. • The local optimal solution is got by competition game algorithm for dispatch set. • The global optimal solution is got by cooperative game algorithm between two sets.

  10. The improvement of maintenance service for traction networks equipment on the base of process approach

    Directory of Open Access Journals (Sweden)

    D. V. Mironov

    2014-12-01

    Full Text Available Purpose. The new methods development for improving the maintenance service for equipment of traction networks in order to increase its efficiency and quality. Methodology. In world practice of solving problems related to the quality of products and services is usually achieved by introducing quality management system in to the enterprises. The provisions of quality management system were used for solving the problem. The technologies of process engineering were used for describing the main stages of maintenance service. Findings. The development of high-speed movement and growth of its intensity, the use of electric rolling stock of a new generation require the introduction of new methods diagnostics of equipment technical state and improvement of the existing maintenance system and repair of power supply. Developing a model of business-processes, their optimization with using techniques of process engineering and system management is needed for the transition to the management system based on the process approach. From the standpoint of the process approach and in accordance with the requirements of the quality management system (ISO 9001-2009, the operation of the E (Department of electrification and power supply infrastructure sector is represented as a scheme of business-processes in which the guaranteed supply with electricity of railway and third-party consumers is defined as the main business-process of management. Each of the sub-process of power supply for consumers is described in details. The use methods and main stages of process approach for sample management system reorganization were investigated. The methodology and the application method of PDCA (Plan-Do-Check-Act closed loop to the equipment maintenance system were described. The monitoring process of traction networks maintenance using the process approach was divided into components after investigations. The technical documentation of maintenance service was investigated in

  11. Maintenance Mechanics Technical Terms. English-Thai Lexicon. Introduction to Maintenance Mechanics. Thai Version. Multi-Cultural Competency-Based Vocational/Technical Curricula Series.

    Science.gov (United States)

    Shin, Masako T.

    This English-Thai lexicon and program introduction for maintenance mechanics is one of eight documents in the Multicultural Competency-Based Vocational/Technical Curricula Series. It is intended for use in postsecondary, adult, and preservice teacher and administrator education. The first two sections provide Thai equivalencies of English…

  12. Multi-Cultural Competency-Based Vocational Curricula. Maintenance Mechanics. Multi-Cultural Competency-Based Vocational/Technical Curricula Series.

    Science.gov (United States)

    Hepburn, Larry; Shin, Masako

    This document, one of eight in a multi-cultural competency-based vocational/technical curricula series, is on maintenance mechanics. This program is designed to run 40 weeks and cover 5 instructional areas: basic electricity (14 weeks); maintenance and repair of heating (4 weeks); maintenance and repair of air conditioning (12 weeks); maintenance…

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

    DEFF Research Database (Denmark)

    Ramirez, José Rangel

    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....... In this work, a framework for optimal risk-based inspection and maintenance planning for Offshore Wind Turbines (OWT) is developed. Fatigue prone details (in cast iron and welded steel) at the jacket or tripod steel support structures are addressed. For wind farms additional efforts are needed when wake...... 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...

  14. Managing data warehouse metadata using the Web: A Web-based DBA maintenance tool suite

    Energy Technology Data Exchange (ETDEWEB)

    Yow, T. [Oak Ridge National Lab., TN (United States); Grubb, J.; Jennings, S. [Univ. of Tennessee, Knoxville, TN (United States)

    1998-12-31

    The Oak Ridge National Laboratory (ORNL) Distributed Active Archive Center (DAAC), which is associated with NASA`s Earth Observing System Data and Information System (EOSDIS), provides access to datasets used in environmental research. As a data warehouse for NASA, the ORNL DAAC archives and distributes data from NASA`s ground-based field experiments. In order to manage its large and diverse data holdings, the DAAC has mined metadata that is stored in several Sybase databases. However, the task of managing the metadata itself has become such a complicated task that the DAAC has developed a Web-based Graphical User Interface (GUI) called the DBA maintenance Tool Suite. This Web-based tool allows the DBA to maintain the DAAC`s metadata databases with the click of a mouse button. This tool greatly reduces the complexities of database maintenance and facilitates the task of data delivery to the DAAC`s user community.

  15. Framework for Risk-based Planning of Operation and Maintenance for Offshore Wind Turbines

    DEFF Research Database (Denmark)

    Sørensen, John Dalsgaard

    2009-01-01

    For offshore wind turbines, costs to operation and maintenance (OM) are substantial. This paper describes a risk-based life cycle approach for optimal planning of OM. The approach is based on pre-posterior Bayesian decision theory, and can be used both to overall, initial planning of OM, and to s......For offshore wind turbines, costs to operation and maintenance (OM) are substantial. This paper describes a risk-based life cycle approach for optimal planning of OM. The approach is based on pre-posterior Bayesian decision theory, and can be used both to overall, initial planning of OM......, and to sequential optimal decision making on planning of OM taking into account new information. Deterioration mechanisms such as fatigue, corrosion, wear and erosion are associated with significant uncertainty. Observations of the degree of damage can increase the reliability of predictions, especially...... in connection with condition-based maintenance. The approach can be used for gearboxes, generators, fatigue cracks, corrosion, etc. This paper also describes how probabilistic indicators can be used to quantify indirect information about the damage state for critical components, e.g. gearboxes....

  16. Improving Legacy Aircraft Systems Through Condition-Based Maintenance: An H-60 Case Study

    Science.gov (United States)

    2014-09-01

    Multifunction Display MMP Monthly Maintenance Plan MOP measure of performance MRC Maintenance Requirement Card MTBM Mean Time Between Maintenance NAE ...Model/Series TD technical directive TM Type Maintenance Code VGA Value Gap Analysis VIB-100 Vibration Analysis Manual (ATABS) xv VIB-200...preventive maintenance. (This includes on-equipment repair, removal, and replacement of defective components.) e. Incorporation of TDs , less SE

  17. 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

  18. Advanced maintenance strategies for power plant operators - introducing inter-plant life cycle management. ZES research focus 'condition-based maintenance in power engineering'

    International Nuclear Information System (INIS)

    Graeber, U.

    2003-01-01

    The optimisation of maintenance activities observed in recent years can be attributed above all to the use and continuing development of testing and diagnostic techniques, to the increased level of system and component automation and to more efficient work organisation. Despite the considerable success of these efforts, the potential for further cost reductions is still far from exhausted. The risks connected to reliability, availability and safety need to be analysed in greater detail in order to ensure the sustainability of the savings already achieved as well as those yet to be realised. The systematic application of condition-based maintenance and the introduction of structured life cycle management are essential prerequisites. Within the framework of its ''Condition-Based Maintenance in Power Engineering'' research focus, the Energy Research Centre (ZES) has set up a specialist network in which experts from various institutes belonging to the Faculty of Mechanical Engineering and the Faculty of Informatic, Electrical Engineering and Information Technology can develop interdisciplinary solutions for advanced maintenance strategies. The ZES offers the industry a platform for cooperating on current issues relating to the supply of energy and supports the movement towards sustainable improvements to competitiveness through research and consulting activities. It applies professional project and quality management procedures to ensure that contracts covering interdisciplinary topics and projects are handled in a coherent manner. (orig.)

  19. Advanced maintenance strategies for power plant operators - introducing inter-plant life cycle management. ZES research focus 'condition-based maintenance in power engineering'

    Energy Technology Data Exchange (ETDEWEB)

    Graeber, U.

    2003-07-01

    The optimisation of maintenance activities observed in recent years can be attributed above all to the use and continuing development of testing and diagnostic techniques, to the increased level of system and component automation and to more efficient work organisation. Despite the considerable success of these efforts, the potential for further cost reductions is still far from exhausted. The risks connected to reliability, availability and safety need to be analysed in greater detail in order to ensure the sustainability of the savings already achieved as well as those yet to be realised. The systematic application of condition-based maintenance and the introduction of structured life cycle management are essential prerequisites. Within the framework of its ''Condition-Based Maintenance in Power Engineering'' research focus, the Energy Research Centre (ZES) has set up a specialist network in which experts from various institutes belonging to the Faculty of Mechanical Engineering and the Faculty of Informatic, Electrical Engineering and Information Technology can develop interdisciplinary solutions for advanced maintenance strategies. The ZES offers the industry a platform for cooperating on current issues relating to the supply of energy and supports the movement towards sustainable improvements to competitiveness through research and consulting activities. It applies professional project and quality management procedures to ensure that contracts covering interdisciplinary topics and projects are handled in a coherent manner. (orig.)

  20. An optimization method for condition based maintenance of aircraft fleet considering prognostics uncertainty.

    Science.gov (United States)

    Feng, Qiang; Chen, Yiran; Sun, Bo; Li, Songjie

    2014-01-01

    An optimization method for condition based maintenance (CBM) of aircraft fleet considering prognostics uncertainty is proposed. The CBM and dispatch process of aircraft fleet is analyzed first, and the alternative strategy sets for single aircraft are given. Then, the optimization problem of fleet CBM with lower maintenance cost and dispatch risk is translated to the combinatorial optimization problem of single aircraft strategy. Remain useful life (RUL) distribution of the key line replaceable Module (LRM) has been transformed into the failure probability of the aircraft and the fleet health status matrix is established. And the calculation method of the costs and risks for mission based on health status matrix and maintenance matrix is given. Further, an optimization method for fleet dispatch and CBM under acceptable risk is proposed based on an improved genetic algorithm. Finally, a fleet of 10 aircrafts is studied to verify the proposed method. The results shows that it could realize optimization and control of the aircraft fleet oriented to mission success.

  1. An All-Recombinant Protein-Based Culture System Specifically Identifies Hematopoietic Stem Cell Maintenance Factors.

    Science.gov (United States)

    Ieyasu, Aki; Ishida, Reiko; Kimura, Takaharu; Morita, Maiko; Wilkinson, Adam C; Sudo, Kazuhiro; Nishimura, Toshinobu; Ohehara, Jun; Tajima, Yoko; Lai, Chen-Yi; Otsu, Makoto; Nakamura, Yukio; Ema, Hideo; Nakauchi, Hiromitsu; Yamazaki, Satoshi

    2017-03-14

    Hematopoietic stem cells (HSCs) are considered one of the most promising therapeutic targets for the treatment of various blood disorders. However, due to difficulties in establishing stable maintenance and expansion of HSCs in vitro, their insufficient supply is a major constraint to transplantation studies. To solve these problems we have developed a fully defined, all-recombinant protein-based culture system. Through this system, we have identified hemopexin (HPX) and interleukin-1α as responsible for HSC maintenance in vitro. Subsequent molecular analysis revealed that HPX reduces intracellular reactive oxygen species levels within cultured HSCs. Furthermore, bone marrow immunostaining and 3D immunohistochemistry revealed that HPX is expressed in non-myelinating Schwann cells, known HSC niche constituents. These results highlight the utility of this fully defined all-recombinant protein-based culture system for reproducible in vitro HSC culture and its potential to contribute to the identification of factors responsible for in vitro maintenance, expansion, and differentiation of stem cell populations. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

  2. An All-Recombinant Protein-Based Culture System Specifically Identifies Hematopoietic Stem Cell Maintenance Factors

    Directory of Open Access Journals (Sweden)

    Aki Ieyasu

    2017-03-01

    Full Text Available Hematopoietic stem cells (HSCs are considered one of the most promising therapeutic targets for the treatment of various blood disorders. However, due to difficulties in establishing stable maintenance and expansion of HSCs in vitro, their insufficient supply is a major constraint to transplantation studies. To solve these problems we have developed a fully defined, all-recombinant protein-based culture system. Through this system, we have identified hemopexin (HPX and interleukin-1α as responsible for HSC maintenance in vitro. Subsequent molecular analysis revealed that HPX reduces intracellular reactive oxygen species levels within cultured HSCs. Furthermore, bone marrow immunostaining and 3D immunohistochemistry revealed that HPX is expressed in non-myelinating Schwann cells, known HSC niche constituents. These results highlight the utility of this fully defined all-recombinant protein-based culture system for reproducible in vitro HSC culture and its potential to contribute to the identification of factors responsible for in vitro maintenance, expansion, and differentiation of stem cell populations.

  3. Initiation and Maintenance of Fitness Center Utilization in an Incentive-Based Employer Wellness Program.

    Science.gov (United States)

    Abraham, Jean Marie; Crespin, Daniel J; Rothman, Alexander J

    2015-09-01

    To investigate the initiation and maintenance of participation in an employer-based wellness program that provides financial incentives for fitness center utilization. Using multivariate analysis, we investigated how employees' demographics, health status, exercise-related factors, and lifestyle change preferences affect program participation. Forty-two percent of eligible employees participated in the program, and 24% earned a $20 incentive at least once by utilizing a gym eight times or more in a month. On average, participants utilized fitness centers 7.0 months each year and earned credit 4.5 months. Participants' utilization diminished after their first year in the program. Factors associated with initiation and maintenance of fitness center utilization were similar. Declining utilization over time raises concern about the long-run effectiveness of fitness-focused wellness programs. Employers may want to consider additional levers to positively reinforce participation.

  4. Exercício físico no ganho de peso e resultados perinatais em gestantes com sobrepeso e obesidade: uma revisão sistemática de ensaios clínicos

    Directory of Open Access Journals (Sweden)

    Simony Lira do Nascimento

    2011-03-01

    Full Text Available Esta revisão objetivou avaliar os efeitos do exercício físico no ganho de peso e nos resultados perinatais de gestantes com sobrepeso e obesidade, através de revisão sistemática da literatura em bases de dados específicas: MEDLINE/PubMed, EMBASE, SciELO e LILACS. Foram incluídos dez ensaios clínicos que avaliaram a efetividade do exercício combinado ou não com dieta no controle do ganho de peso gestacional. Três estudos são randomizados e a qualidade metodológica foi avaliada através do CONSORT 2010 Checklist, porém nenhum deles cumpriu todos os critérios. Quatro estudos obtiveram diferença quanto ao ganho de peso entre os grupos. A maioria dos estudos (60% não demonstrou diferença quanto aos resultados perinatais (via de parto, idade gestacional ao nascer, peso do recém-nascido. Poucos estudos confirmam o efeito positivo do exercício no controle do ganho de peso gestacional, necessitando mais pesquisas neste sentido. O exercício em intensidade leve a moderada parece não ser determinante nos resultados perinatais, sendo uma prática segura para gestantes com sobrepeso e obesidade.

  5. Bayesian based Diagnostic Model for Condition based Maintenance of Offshore Wind Farms

    DEFF Research Database (Denmark)

    Asgarpour, Masoud; Sørensen, John Dalsgaard

    2018-01-01

    Operation and maintenance costs are a major contributor to the Levelized Cost of Energy for electricity produced by offshore wind and can be significantly reduced if existing corrective actions are performed as efficiently as possible and if future corrective actions are avoided by performing suf...

  6. Application prototype of a model-based expert system to the maintenance of a MAN

    Science.gov (United States)

    Hopfmueller, Heinrich; Kehl, Walter; Schapeler, Gottfried

    1993-10-01

    This paper describes the work done and results achieved in implementing a fault management prototype for a Metropolitan Area Network (MAN) switching system, the GMAN (GMS Fault Management Prototype for a MAN). The GMAN is implemented using the Generic Maintenance System (GMS) which has been developed by the RACE project AIM (R1006). The GMS is a model based expert system toolset (`2nd generation XPS') comprising components for knowledge acquisition, knowledge representation, model based reasoning, human machine interface, and dialogue design. The GMS supports automatic fault management from receiving and treating fault events to guiding an operator through a repair procedure.

  7. 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.

  8. Probability-based assessment and maintenance of welded joints damaged by fatigue

    International Nuclear Information System (INIS)

    Cremona, C.; Lukic, M.

    1998-01-01

    This paper presents a probabilistic reliability assessment procedure for steel components damaged by fatigue. The study combines the structural reliability theory with a maintenance strategy. The fatigue assessment model is based on a modelisation of the fatigue phenomenon issued from the principles of fracture mechanics theory. The safety margin includes the crack growth propagation and allows to treat fatigue damage in a general manner. Damaging cycles and non damaging cycles are distinguished. The sensitivity study of the different parameters shows that some variables can be taken as deterministic. Applications are made on a welded joint 'stiffener/bottom-plate' of a typical steel bridge. The model is then used for taking into account inspection results. Non destructive inspection (NDI) techniques are also used for updating failure probabilities. The results show their ability to be inserted in a maintenance strategy for optimizing the next inspection time. This has led to define cost functions related to the total maintenance cost; this cost is then minimized for determining the optimal next inspection time. An example of welded joint cracked by fatigue highlights the different concepts. The approach presented in the paper is not only restrained to fatigue problems, but can be applied to a wide variety of degrading phenomena. (orig.)

  9. Generator maintenance scheduling in power systems using metaheuristic-based hybrid approaches

    Energy Technology Data Exchange (ETDEWEB)

    Dahal, Keshav P. [School of Informatics, University of Bradford, Bradford (United Kingdom); Chakpitak, Nopasit [College of Arts, Media and Technology, Chiang Mai University, Chiang Mai (Thailand)

    2007-05-15

    The effective maintenance scheduling of power system generators is very important for the economical and reliable operation of a power system. This represents a tough scheduling problem which continues to present a challenge for efficient optimization solution techniques. This paper presents the application of metaheuristic approaches, such as a genetic algorithm (GA), simulated annealing (SA) and their hybrid for generator maintenance scheduling (GMS) in power systems using an integer representation. This paper mainly focuses on the application of GA/SA and GA/SA/heuristic hybrid approaches. GA/SA hybrid uses the probabilistic acceptance criterion of SA within the GA framework. GA/SA/heuristic hybrid combines heuristic approaches within the GA/SA hybrid to seed the initial population. A case study is formulated in this paper as an integer programming problem using a reliability-based objective function and typical problem constraints. The implementation and performance of the metaheuristic approaches and their hybrid for the test case study are discussed. The results obtained are promising and show that the hybrid approaches are less sensitive to the variations of technique parameters and offer an effective alternative for solving the generator maintenance scheduling problem. (author)

  10. Partial maintenance of auditory-based cognitive training benefits in older adults.

    Science.gov (United States)

    Anderson, Samira; White-Schwoch, Travis; Choi, Hee Jae; Kraus, Nina

    2014-09-01

    The potential for short-term training to improve cognitive and sensory functions in older adults has captured the public's interest. Initial results have been promising. For example, eight weeks of auditory-based cognitive training decreases peak latencies and peak variability in neural responses to speech presented in a background of noise and instills gains in speed of processing, speech-in-noise recognition, and short-term memory in older adults. But while previous studies have demonstrated short-term plasticity in older adults, we must consider the long-term maintenance of training gains. To evaluate training maintenance, we invited participants from an earlier training study to return for follow-up testing six months after the completion of training. We found that improvements in response peak timing to speech in noise and speed of processing were maintained, but the participants did not maintain speech-in-noise recognition or memory gains. Future studies should consider factors that are important for training maintenance, including the nature of the training, compliance with the training schedule, and the need for booster sessions after the completion of primary training. Copyright © 2014 Elsevier Ltd. All rights reserved.

  11. Refinement of the Diatom Episome Maintenance Sequence and Improvement of Conjugation-based DNA Delivery Methods

    Directory of Open Access Journals (Sweden)

    Rachel E Diner

    2016-08-01

    Full Text Available Conjugation of episomal plasmids from bacteria to diatoms advances diatom genetic manipulation by simplifying transgene delivery and providing a stable and consistent gene expression platform. To reach its full potential, this nascent technology requires new optimized expression vectors and a deeper understanding of episome maintenance. Here we present the development of an additional diatom vector (pPtPBR1, based on the parent plasmid pBR322, to add a plasmid maintained at medium copy number in E. coli to the diatom genetic toolkit. Using this new vector, we evaluated the contribution of individual yeast DNA elements comprising the 1.4-kb tripartite CEN6-ARSH4-HIS3 sequence that enables episome maintenance in P. tricornutum. While various combinations of these individual elements enable efficient conjugation and high ex-conjugant yield in P. tricornutum, individual elements alone do not. Conjugation of episomes containing CEN6-ARSH4 and a small sequence from the low GC content 3’ end of HIS3 produced the highest number of diatom ex-conjugant colonies, resulting in a smaller and more efficient vector design. Our findings suggest that the CEN6 and ARSH4 sequences function differently in yeast and diatoms, and that low GC content regions of greater than ~500 bp are a potential indicator of a functional diatom episome maintenance sequence. Additionally, we have developed improvements to the conjugation protocol including a higher-throughput option utilizing 12-well plates, and plating methods that improve ex-conjugant yield and reduce time and materials required for the conjugation protocol. The data presented offer additional information regarding the mechanism by which the yeast-derived sequence enables diatom episome maintenance, and demonstrate options for flexible vector design.

  12. Refinement of the Diatom Episome Maintenance Sequence and Improvement of Conjugation-Based DNA Delivery Methods.

    Science.gov (United States)

    Diner, Rachel E; Bielinski, Vincent A; Dupont, Christopher L; Allen, Andrew E; Weyman, Philip D

    2016-01-01

    Conjugation of episomal plasmids from bacteria to diatoms advances diatom genetic manipulation by simplifying transgene delivery and providing a stable and consistent gene expression platform. To reach its full potential, this nascent technology requires new optimized expression vectors and a deeper understanding of episome maintenance. Here, we present the development of an additional diatom vector (pPtPBR1), based on the parent plasmid pBR322, to add a plasmid maintained at medium copy number in Escherichia coli to the diatom genetic toolkit. Using this new vector, we evaluated the contribution of individual yeast DNA elements comprising the 1.4-kb tripartite CEN6-ARSH4-HIS3 sequence that enables episome maintenance in Phaeodactylum tricornutum. While various combinations of these individual elements enable efficient conjugation and high exconjugant yield in P. tricornutum, individual elements alone do not. Conjugation of episomes containing CEN6-ARSH4 and a small sequence from the low GC content 3' end of HIS3 produced the highest number of diatom exconjugant colonies, resulting in a smaller and more efficient vector design. Our findings suggest that the CEN6 and ARSH4 sequences function differently in yeast and diatoms, and that low GC content regions of greater than ~500 bp are a potential indicator of a functional diatom episome maintenance sequence. Additionally, we have developed improvements to the conjugation protocol including a high-throughput option utilizing 12-well plates and plating methods that improve exconjugant yield and reduce time and materials required for the conjugation protocol. The data presented offer additional information regarding the mechanism by which the yeast-derived sequence enables diatom episome maintenance and demonstrate options for flexible vector design.

  13. Interactive computer-based interventions for weight loss or weight maintenance in overweight or obese people

    Science.gov (United States)

    Wieland, L. Susan; Falzon, Louise; Sciamanna, Chris N; Trudeau, Kimberlee J; Folse, Suzanne Brodney; Schwartz, Joseph E; Davidson, Karina W

    2014-01-01

    Background The World Health Organization (WHO) estimates that the number of obese or overweight individuals worldwide will increase to 1.5 billion by 2015. Chronic diseases associated with overweight or obesity include diabetes, heart disease, hypertension and stroke. Objectives To assess the effects of interactive computer-based interventions for weight loss or weight maintenance in overweight or obese people. Search methods We searched several electronic databases, including CENTRAL, MEDLINE, EMBASE, CINAHL, LILACS and PsycINFO, through 25 May 2011. We also searched clinical trials registries to identify studies. We scanned reference lists of included studies and relevant systematic reviews. Selection criteria Studies were included if they were randomized controlled trials or quasi-randomized controlled trials that evaluated interactive computer-based weight loss or weight maintenance programs in adults with overweight or obesity. We excluded trials if the duration of the intervention was less than four weeks or the loss to follow-up was greater than 20% overall. Data collection and analysis Two authors independently extracted study data and assessed risk of bias. Where interventions, control conditions, outcomes and time frames were similar between studies, we combined study data using meta-analysis. Main results We included 14 weight loss studies with a total of 2537 participants, and four weight maintenance studies with a total of 1603 participants. Treatment duration was between four weeks and 30 months. At six months, computer-based interventions led to greater weight loss than minimal interventions (mean difference (MD) −1.5 kg; 95% confidence interval (CI) −2.1 to −0.9; two trials) but less weight loss than in-person treatment (MD 2.1 kg; 95% CI 0.8 to 3.4; one trial). At six months, computer-based interventions were superior to a minimal control intervention in limiting weight regain (MD −0.7 kg; 95% CI −1.2 to −0.2; two trials), but not

  14. Operations and Maintenance Manual for Expanded Bioventing System at Buildings 2034/2035, Fairchild Air Force Base, Washington

    National Research Council Canada - National Science Library

    1996-01-01

    This Operations and Maintenance (O&M) Manual has been created as a guide for monitoring and maintaining the performance of the full-scale bioventing blower system and vent well plumbing at Fairchild Air Force Base (AFB), Washington...

  15. Condition-based maintenance effectiveness for series–parallel power generation system—A combined Markovian simulation model

    International Nuclear Information System (INIS)

    Azadeh, A.; Asadzadeh, S.M.; Salehi, N.; Firoozi, M.

    2015-01-01

    Condition-based maintenance (CBM) is an increasingly applicable policy in the competitive marketplace as a means of improving equipment reliability and efficiency. Not only has maintenance a close relationship with safety but its costs also make it even more attractive issue for researchers. This study proposes a model to evaluate the effectiveness of CBM policy compared to two other maintenance policies: Corrective Maintenance (CM) and Preventive Maintenance (PM). Maintenance policies are compared through two system performance indicators: reliability and cost. To estimate the reliability and costs of the system, the proposed Markovian discrete-event simulation model is developed under each of these policies. The applicability and usefulness of the proposed Markovian simulation model is illustrated for a series–parallel power generation system. The simulated characteristics of CBM system include its prognostics efficiency to estimate remaining useful life of the equipment. Results show that with an efficient prognostics, CBM policy is an effective strategy compared to other maintenance strategies. - Highlights: • A model is developed to evaluate the effectiveness of CBM policy. • Maintenance policies are compared through reliability and cost. • A Markovian simulation model is developed. • A series–parallel power generation system is considered. • CBM is an effective strategy compared to others

  16. Risk-Based Operation and Maintenance of Offshore Wind Turbines using Bayesian Networks

    DEFF Research Database (Denmark)

    Nielsen, Jannie Jessen; Sørensen, John Dalsgaard

    2011-01-01

    the lifetime. Two different approaches are used; one uses a threshold value of the failure probability, and one uses a Limited Memory Influence Diagram. Both methods are tested for an application example using MonteCarlo sampling, and they are both found to be efficient and equally good.......For offshore wind farms, the costs due to operation and maintenance are large, and more optimal planning has the potential of reducing these costs. This paper presents how Bayesian networks can be used for risk-based inspection planning, where the inspection plans are updated each year through...

  17. 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

    2012-05-01

    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.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    1996-11-01

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

  19. A circadian rhythm in skill-based errors in aviation maintenance.

    Science.gov (United States)

    Hobbs, Alan; Williamson, Ann; Van Dongen, Hans P A

    2010-07-01

    In workplaces where activity continues around the clock, human error has been observed to exhibit a circadian rhythm, with a characteristic peak in the early hours of the morning. Errors are commonly distinguished by the nature of the underlying cognitive failure, particularly the level of intentionality involved in the erroneous action. The Skill-Rule-Knowledge (SRK) framework of Rasmussen is used widely in the study of industrial errors and accidents. The SRK framework describes three fundamental types of error, according to whether behavior is under the control of practiced sensori-motor skill routines with minimal conscious awareness; is guided by implicit or explicit rules or expertise; or where the planning of actions requires the conscious application of domain knowledge. Up to now, examinations of circadian patterns of industrial errors have not distinguished between different types of error. Consequently, it is not clear whether all types of error exhibit the same circadian rhythm. A survey was distributed to aircraft maintenance personnel in Australia. Personnel were invited to anonymously report a safety incident and were prompted to describe, in detail, the human involvement (if any) that contributed to it. A total of 402 airline maintenance personnel reported an incident, providing 369 descriptions of human error in which the time of the incident was reported and sufficient detail was available to analyze the error. Errors were categorized using a modified version of the SRK framework, in which errors are categorized as skill-based, rule-based, or knowledge-based, or as procedure violations. An independent check confirmed that the SRK framework had been applied with sufficient consistency and reliability. Skill-based errors were the most common form of error, followed by procedure violations, rule-based errors, and knowledge-based errors. The frequency of errors was adjusted for the estimated proportion of workers present at work/each hour of the day

  20. Data Base Development of Automobile and Light Truck Maintenance : Volume II. Appendix E.

    Science.gov (United States)

    1978-08-01

    The document contains the scheduled maintenance data sheets and total cost summaries--both scheduled and unscheduled maintenance (Life cycle cost for Dealers, life cycle cost for Service Stations, life cycle cost for Independent Repair, and scheduled...

  1. Data Base Development of Automobile and Light Truck Maintenance : Volume III. Appendix F.

    Science.gov (United States)

    1978-08-01

    The document contains the scheduled maintenance data sheets and total cost summaries--both scheduled and unscheduled maintenance (Life cycle cost for Dealers, life cycle cost for Service Stations, life cycle cost for Independent Repair, and scheduled...

  2. Maintenance-based prognostics of nuclear plant equipment for long-term operation

    International Nuclear Information System (INIS)

    Welz, Zachary; Coble, Jamie; Upadhyaya, Belle; Hines, Wes

    2017-01-01

    While industry understands the importance of keeping equipment operational and well maintained, the importance of tracking maintenance information in reliability models is often overlooked. Prognostic models can be used to predict the failure times of critical equipment, but more often than not, these models assume that all maintenance actions are the same or do not consider maintenance at all. This study investigates the influence of integrating maintenance information on prognostic model prediction accuracy. By incorporating maintenance information to develop maintenance-dependent prognostic models, prediction accuracy was improved by more than 40% compared with traditional maintenance-independent models. This study acts as a proof of concept, showing the importance of utilizing maintenance information in modern prognostics for industrial equipment

  3. Maintenance-based prognostics of nuclear plant equipment for long-term operation

    Energy Technology Data Exchange (ETDEWEB)

    Welz, Zachary; Coble, Jamie; Upadhyaya, Belle; Hines, Wes [University of Tennessee, Knoxville (United States)

    2017-08-15

    While industry understands the importance of keeping equipment operational and well maintained, the importance of tracking maintenance information in reliability models is often overlooked. Prognostic models can be used to predict the failure times of critical equipment, but more often than not, these models assume that all maintenance actions are the same or do not consider maintenance at all. This study investigates the influence of integrating maintenance information on prognostic model prediction accuracy. By incorporating maintenance information to develop maintenance-dependent prognostic models, prediction accuracy was improved by more than 40% compared with traditional maintenance-independent models. This study acts as a proof of concept, showing the importance of utilizing maintenance information in modern prognostics for industrial equipment.

  4. Carotenoid maintenance handicap and the physiology of carotenoid-based signalisation of health

    Science.gov (United States)

    Vinkler, Michal; Albrecht, Tomáš

    2010-01-01

    Despite a reasonable scientific interest in sexual selection, the general principles of health signalisation via ornamental traits remain still unresolved in many aspects. This is also true for the mechanism preserving honesty of carotenoid-based signals. Although it is widely accepted that this type of ornamentation reflects an allocation trade-off between the physiological utilisation of carotenoids (mainly in antioxidative processes) and their deposition in ornaments, some recent evidence suggests more complex interactions. Here, we further develop the models currently proposed to explain the honesty of carotenoid-based signalisation of heath status by adding the handicap principle concept regulated by testosterone. We propose that under certain circumstances carotenoids may be dangerous for the organism because they easily transform into toxic cleavage products. When reserves of other protective antioxidants are insufficient, physiological trade-offs may exist between maintenance of carotenoids for ornament expression and their removal from the body. Furthermore, we suggest that testosterone which enhances ornamentation by increasing carotenoid bioavailability may also promote oxidative stress and hence lower antioxidant reserves. The presence of high levels of carotenoids required for high-quality ornament expression may therefore represent a handicap and only individuals in prime health could afford to produce elaborate colourful ornaments. Although further testing is needed, this ‘carotenoid maintenance handicap’ hypothesis may offer a new insight into the physiological aspects of the relationship between carotenoid function, immunity and ornamentation.

  5. Maintenance of algal endosymbionts in Paramecium bursaria: a simple model based on population dynamics.

    Science.gov (United States)

    Iwai, Sosuke; Fujiwara, Kenji; Tamura, Takuro

    2016-09-01

    Algal endosymbiosis is widely distributed in eukaryotes including many protists and metazoans, and plays important roles in aquatic ecosystems, combining phagotrophy and phototrophy. To maintain a stable symbiotic relationship, endosymbiont population size in the host must be properly regulated and maintained at a constant level; however, the mechanisms underlying the maintenance of algal endosymbionts are still largely unknown. Here we investigate the population dynamics of the unicellular ciliate Paramecium bursaria and its Chlorella-like algal endosymbiont under various experimental conditions in a simple culture system. Our results suggest that endosymbiont population size in P. bursaria was not regulated by active processes such as cell division coupling between the two organisms, or partitioning of the endosymbionts at host cell division. Regardless, endosymbiont population size was eventually adjusted to a nearly constant level once cells were grown with light and nutrients. To explain this apparent regulation of population size, we propose a simple mechanism based on the different growth properties (specifically the nutrient requirements) of the two organisms, and based from this develop a mathematical model to describe the population dynamics of host and endosymbiont. The proposed mechanism and model may provide a basis for understanding the maintenance of algal endosymbionts. © 2015 Society for Applied Microbiology and John Wiley & Sons Ltd.

  6. Cryogenics maintenance strategy

    Science.gov (United States)

    Cruzat, Fabiola

    2012-09-01

    ALMA is an interferometer composed of 66 independent systems, with specific maintenance requirements for each subsystem. To optimize the observation time and reduce downtime maintenance, requirements are very demanding. One subsystem with high maintenance efforts is cryogenics and vacuum. To organize the maintenance, the Cryogenic and Vacuum department is using and implementing different tools. These are monitoring and problem reporting systems and CMMS. This leads to different maintenance approaches: Preventive Maintenance, Corrective Maintenance and Condition Based Maintenance. In order to coordinate activities with other departments the preventive maintenance schedule is kept as flexible as systems allow. To cope with unavoidable failures, the team has to be prepared to work under any condition with the spares on time. Computerized maintenance management system (CMMS) will help to manage inventory control for reliable spare part handling, the correct record of work orders and traceability of maintenance activities. For an optimized approach the department is currently evaluating where preventive or condition based maintenance applies to comply with the individual system demand. Considering the change from maintenance contracts to in-house maintenance will help to minimize costs and increase availability of parts. Due to increased number of system and tasks the cryo team needs to grow. Training of all staff members is mandatory, in depth knowledge must be built up by doing complex maintenance activities in the Cryo group, use of advanced computerized metrology systems.

  7. Performance-based maintenance procurement by Dutch housing associations - Working paper ¿

    NARCIS (Netherlands)

    Straub, A.; van Mossel, H.J.

    2005-01-01

    Maintenance works are component services that are part of the final housing service to the tenant. Because main building maintenance works are designed each time again, it can be compared to product (service) development. With different types of cooperation with maintenance contractors, the degree

  8. Comparative study of heuristics algorithms in solving flexible job shop scheduling problem with condition based maintenance

    Directory of Open Access Journals (Sweden)

    Yahong Zheng

    2014-05-01

    Full Text Available Purpose: This paper focuses on a classic optimization problem in operations research, the flexible job shop scheduling problem (FJSP, to discuss the method to deal with uncertainty in a manufacturing system.Design/methodology/approach: In this paper, condition based maintenance (CBM, a kind of preventive maintenance, is suggested to reduce unavailability of machines. Different to the simultaneous scheduling algorithm (SSA used in the previous article (Neale & Cameron,1979, an inserting algorithm (IA is applied, in which firstly a pre-schedule is obtained through heuristic algorithm and then maintenance tasks are inserted into the pre-schedule scheme.Findings: It is encouraging that a new better solution for an instance in benchmark of FJSP is obtained in this research. Moreover, factually SSA used in literature for solving normal FJSPPM (FJSP with PM is not suitable for the dynamic FJSPPM. Through application in the benchmark of normal FJSPPM, it is found that although IA obtains inferior results compared to SSA used in literature, it performs much better in executing speed.Originality/value: Different to traditional scheduling of FJSP, uncertainty of machines is taken into account, which increases the complexity of the problem. An inserting algorithm (IA is proposed to solve the dynamic scheduling problem. It is stated that the quality of the final result depends much on the quality of the pre-schedule obtained during the procedure of solving a normal FJSP. In order to find the best solution of FJSP, a comparative study of three heuristics is carried out, the integrated GA, ACO and ABC. In the comparative study, we find that GA performs best in the three heuristic algorithms. Meanwhile, a new better solution for an instance in benchmark of FJSP is obtained in this research.

  9. Optimal condition-based maintenance decisions for systems with dependent stochastic degradation of components

    International Nuclear Information System (INIS)

    Hong, H.P.; Zhou, W.; Zhang, S.; Ye, W.

    2014-01-01

    Components in engineered systems are subjected to stochastic deterioration due to the operating environmental conditions, and the uncertainty in material properties. The components need to be inspected and possibly replaced based on preventive or failure replacement criteria to provide the intended and safe operation of the system. In the present study, we investigate the influence of dependent stochastic degradation of multiple components on the optimal maintenance decisions. We use copula to model the dependent stochastic degradation of components, and formulate the optimal decision problem based on the minimum expected cost rule and the stochastic dominance rules. The latter is used to cope with decision maker's risk attitude. We illustrate the developed probabilistic analysis approach and the influence of the dependency of the stochastic degradation on the preferred decisions through numerical examples

  10. OPTIMIZING MAINTENANCE PROCESSES ON CUSTOMER SITE IN A DECENTRALIZED ORGANIZATION BASED ON MULTI-SITE TEAMS

    Directory of Open Access Journals (Sweden)

    Jorge Moutinho

    2015-03-01

    Full Text Available This lecture focuses on the complexity to manage and optimize maintenance processes, operations and service tasks to equipments and systems installed at customer sites. Different locations, access and working environment may compromise any standardization of setup's and operations. Multi-site teams based on geographic strategic locations, adds complexity to trainning, communication, supervising and monitoring processes. Logistics and information systems assume relevant rolls to consolidate global performance. Beside efficiency, effectiveness productivity and flexibility, field teams need skills on autonomy responsibility and proactivity. This lecture also explores the needed adaptation of most part of available literature, normally based on production sites, as also of Lean- Kaizen principles to the fact that services can not be stocked, quality is normally more difficult to measure and customer is normally present when and where service is produced.

  11. Evaluation of artillery equipment maintenance support capability based on grey clustering

    Science.gov (United States)

    Zhai, Mei-jie; Gao, Peng

    2017-12-01

    This paper, the theory and method of evaluating the capability of equipment maintenance support in China and abroad are studied, from the point of view of the combat task of artillery troops and the strategic attachment in the future military struggle. This paper establishes the framework of the evaluation Index system of the equipment maintenance support capability of the artillery units, and applies the grey clustering method to the evaluation of the equipment maintenance support capability of the artillery units, and finally evaluates the equipment maintenance and support capability of the artillery brigade as an example, and analyzes the evaluation results. This paper finds out the outstanding problems existing in the maintenance and support of military equipment, and puts forward some constructive suggestions, in order to improve the status of military equipment maintenance and support and improve the level of future equipment maintenance.

  12. Safety constraints applied to an adaptive Bayesian condition-based maintenance optimization model

    International Nuclear Information System (INIS)

    Flage, Roger; Coit, David W.; Luxhøj, James T.; Aven, Terje

    2012-01-01

    A model is described that determines an optimal inspection and maintenance scheme for a deteriorating unit with a stochastic degradation process with independent and stationary increments and for which the parameters are uncertain. This model and resulting maintenance plans offers some distinct benefits compared to prior research because the uncertainty of the degradation process is accommodated by a Bayesian approach and two new safety constraints have been applied to the problem: (1) with a given subjective probability (degree of belief), the limiting relative frequency of one or more failures during a fixed time interval is bounded; or (2) the subjective probability of one or more failures during a fixed time interval is bounded. In the model, the parameter(s) of a condition-based inspection scheduling function and a preventive replacement threshold are jointly optimized upon each replacement and inspection such as to minimize the expected long run cost per unit of time, but also considering one of the specified safety constraints. A numerical example is included to illustrate the effect of imposing each of the two different safety constraints.

  13. Ethnicity- and sex-based discrimination and the maintenance of self-esteem.

    Science.gov (United States)

    Lönnqvist, Jan-Erik; Hennig-Schmidt, Heike; Walkowitz, Gari

    2015-01-01

    The psychological underpinnings of labor market discrimination were investigated by having participants from Israel, the West Bank and Germany (N = 205) act as employers in a stylized employment task in which they ranked, set wages, and imposed a minimum effort level on applicants. State self-esteem was measured before and after the employment task, in which applicant ethnicity and sex were salient. The applicants were real people and all behavior was monetarily incentivized. Supporting the full self-esteem hypothesis of the social identity approach, low self-esteem in women was associated with assigning higher wages to women than to men, and such behavior was related to the maintenance of self-esteem. The narrower hypothesis that successful intergroup discrimination serves to protect self-esteem received broader support. Across all participants, both ethnicity- and sex-based discrimination of out-groups were associated with the maintenance of self-esteem, with the former showing a stronger association than the latter.

  14. Ethnicity- and Sex-Based Discrimination and the Maintenance of Self-Esteem

    Science.gov (United States)

    2015-01-01

    The psychological underpinnings of labor market discrimination were investigated by having participants from Israel, the West Bank and Germany (N = 205) act as employers in a stylized employment task in which they ranked, set wages, and imposed a minimum effort level on applicants. State self-esteem was measured before and after the employment task, in which applicant ethnicity and sex were salient. The applicants were real people and all behavior was monetarily incentivized. Supporting the full self-esteem hypothesis of the social identity approach, low self-esteem in women was associated with assigning higher wages to women than to men, and such behavior was related to the maintenance of self-esteem. The narrower hypothesis that successful intergroup discrimination serves to protect self-esteem received broader support. Across all participants, both ethnicity- and sex-based discrimination of out-groups were associated with the maintenance of self-esteem, with the former showing a stronger association than the latter. PMID:25978646

  15. Pemetrexed Continuation Maintenance versus Conventional Platinum-Based Doublet Chemotherapy in EGFR-Negative Lung Adenocarcinoma: Retrospective Analysis.

    Science.gov (United States)

    Paik, Seung Sook; Hwang, In Kyoung; Park, Myung Jae; Lee, Seung Hyeun

    2018-03-07

    Although targeted therapy and immuno-oncology have shifted the treatment paradigm for lung cancer, platinum-based combination is still the standard of care for advanced non-small cell lung cancer (NSCLC). Pemetrexed continuation maintenance therapy has been approved and increasingly used for patients with nonsquamous NSCLC. However, the efficacy of this strategy has not been proven in patients without driving mutations. The objective of this study was to compare the clinical benefit of pemetrexed continuation maintenance to conventional platinum-based doublet in epidermal growth factor receptor (EGFR)-negative lung adenocarcinoma. A total of 114 patients with EGFR-negative lung adenocarcinoma who were treated with platinum doublet were retrospectively enrolled. We compared the survival rates between patients received pemetrexed maintenance after four-cycled pemetrexed/cisplatin and those received at least four-cycled platinum doublet without maintenance chemotherapy as a first-line treatment. Forty-one patients received pemetrexed maintenance and 73 received conventional platinum doublet. Median progression-free survival (PFS), which was defined as the time from the day of response evaluation after four cycles of chemotherapy to disease progression or death, was significantly higher in the pemetrexed maintenance group compared to conventional group (5.8 months vs. 2.2 months, pmaintenance group (22.3 months vs. 16.1 months, p=0.098). Multivariate analyses showed that pemetrexed maintenance chemotherapy was associated with better PFS (hazard ratio, 0.73; 95% confidence interval, 0.15-0.87). Compared to conventional platinum-based chemotherapy, premetrexed continuation maintenance treatment is associated with better clinical outcome for the patients with EGFR wild-type lung adenocarcinoma. Copyright©2018. The Korean Academy of Tuberculosis and Respiratory Diseases.

  16. Ácido valpróico, cabelos cacheados e ganho de peso

    Directory of Open Access Journals (Sweden)

    Paulo R. M. Bittencourt

    1986-03-01

    Full Text Available A literatura registra a ocorrência de ganho de peso em menos de 20% dos pacientes que recebem ácido valpróico e alterações na textura de fâneros em até 9%. O autor relata o caso de uma paciente de 19 anos que desenvolveu ganho de 13 kg, perda parcial de cabelos seguida de transformação deles de lisos e claros em cacheados e mais escuros, durante tratamento com 1000 mg de ácido valpróico ao dia, com nível sérico de 138,9 mg/ml. Após diminuição da dose para 500 mg ao dia, com nível sérico de 80,5 mg/ml, ela perdeu 7 kg, porém não recuperou a antiga textura dos cabelos. Devido ao completo controle de suas crises de ausência, mioclônicas e tônico-clônicas, jamais obtido com outra medicação, a paciente escolheu manter tratamento com ácido valpróico.

  17. Heuristic guidelines and experimental evaluation of effective augmented-reality based instructions for maintenance in nuclear power plants

    International Nuclear Information System (INIS)

    Yim, Ho Bin; Seong, Poong Hyun

    2010-01-01

    Research highlights: → Augmented reality (AR) instructions were built for NPPs maintenance personnel. → 4-5 pieces of information at a time were optimum for AR instructions in this study. → A large variance in mode no. 5 implies these were also found to be critical amount. → Heuristic guidelines were suggested to make AR instructions more effective. - Abstract: As industrial plants and factories age, their maintenance requirements increase. Because maintenance mistakes directly increase the operating costs of a power plant, maintenance quality is significant concern to plant management. By law, all personnel working with nuclear technology must be re-trained every three years in Korea; however, as the statistical data show, the number of shutdown accidents at nuclear power plants (NPPs) due to maintenance failure is still high and needs to be reduced. Industries have started to adopt various technologies to increase the speed and accuracy of maintenance. Among those technologies, augmented reality (AR) is the latest multimedia presentation technology to be applied to plant maintenance, and it offers superior intuitiveness and user interactivity over other conventional multimedia. This empirical study aims to measure the optimum amounts of information to be delivered at a time and to identify what types of information enhance the learning ability of novices and to suggest heuristic guidelines by which to make effective AR training instructions. In the first experiment, the optimum amount of information in an AR learning environment for novices was found to be 4-5 pieces of information in a chunk by comparing results between a pre-test and an after-test. This result implies that intentionally made chunks help novices learn more effectively. In the second experiment, the AR training instruction based on the suggested heuristic guidelines was slightly more effective than other AR training instructions. Maintenance in nuclear power plants can be more reliable

  18. Fault Detection for Large-Scale Railway Maintenance Equipment Base on Wireless Sensor Networks

    Directory of Open Access Journals (Sweden)

    Junfu Yu

    2014-04-01

    Full Text Available Focusing on the fault detection application for large-scale railway maintenance equipment with the specialties of low-cost, energy efficiency, collecting data of the function units. This paper proposed energy efficiency, convenient installation fault detection application using Sigsbee wireless sensor networks, which Sigsbee is the most widely used protocol based on IEEE 802.15.4. This paper proposed a systematic application from hardware design using STM32F103 chips as processer, to software system. Fault detection application is the basic part of the fault diagnose system, wireless sensor nodes of the fault detection application with different kinds of sensors for verities function units communication by Sigsbee to collecting and sending basic working status data to the home gateway, then data will be sent to the fault diagnose system.

  19. Conference on the exploitation, maintenance and resale of ground-based photovoltaic plants

    International Nuclear Information System (INIS)

    Roesner, Sven; Christmann, Ralf; Bozonnat, Cedric; Le Pivert, Xavier; Vaassen, Willi; Dumoulin, Cedric; Kiefer, Klaus; Semmel, Andreas; Doose, Eckhard; Bion, Alain; Sanches, Frederico; Daval, Xavier; Pampouille, Antoine; Goetze, Holger; Stahl, Wolf-Ruediger; Merere, Karine

    2017-11-01

    This document gathers contributions and debate contents of a conference. A first set of contributions addressed the situation and recent developments of ground-based photovoltaic power plants in France and in Germany with presentations of legal frameworks in these both countries. The second set addressed the optimisation of such power plants: meteorological prediction and follow-up at the service of production, risks to which these power plants are exposed during operation, and the issue of right price and good practices for maintenance contracts for these plants. A round table addressed the issue of the balance between optimisation and established practices in a new economic framework. The next set of contributions addressed reasons for and effects of the resale of photovoltaic fleet during their exploitation: actors and financing solutions, value components, point of attention and legal view on re-financing contracts. A round table discussed trends and success factors for the re-financing of photovoltaic projects

  20. Condition-based dynamic maintenance operations planning and grouping. Application to commercial heavy vehicles

    Energy Technology Data Exchange (ETDEWEB)

    Bouvard, K., E-mail: keomany.bouvard@volvo.co [Volvo Technology, 99 route de Lyon, 69806 Saint Priest cedex (France); Laboratoire d' Automatique de Genie Informatique et Signal - FRE3303 - Polytech' Lille, 59655 Villeneuve d' Ascq (France); Artus, S., E-mail: samuel.artus@volvo.co [Volvo Technology, 99 route de Lyon, 69806 Saint Priest cedex (France); Berenguer, C., E-mail: christophe.berenguer@utt.f [Universite de technologie de Troyes - Institut Charles Delaunay and UMR CNRS 6279 - 12, rue Marie Curie, BP2060, 10010 Troyes cedex (France); Cocquempot, V., E-mail: vincent.cocquempot@univ-lille1.f [Laboratoire d' Automatique de Genie Informatique et Signal - FRE3303 - Polytech' Lille, 59655 Villeneuve d' Ascq (France)

    2011-06-15

    This paper aims at presenting a method to optimize the maintenance planning for a commercial heavy vehicle. Such a vehicle may be considered as a multi-components system. Grouping maintenance operations related to each component reduces the global maintenance cost of the system. Classically, the optimization problem is solved using a priori reliability characteristics of components. Two types of methods may be used, i.e. static or dynamic methods. Static methods provide a fixed maintenance planning, whereas dynamic methods redefine the groups of maintenance operations at each decision time. Dynamic procedures can incorporate component information such as component states or detected failures. For deteriorating systems, reliability characteristics of each component may be estimated thanks to deterioration models and may be updated when a degradation measure is available. This additional information on degradation features allows to better follow the real state of each component and to improve the maintenance planning.

  1. Ganho de produtividade pelo melhoramento genético do arroz irrigado no nordeste do Brasil Yield gain through irrigated rice breeding in the northeast Brazil

    Directory of Open Access Journals (Sweden)

    Flávio Breseghello

    1999-03-01

    Full Text Available Os ganhos genéticos para produtividade obtidos pelo programa de melhoramento do arroz irrigado por inundação na Região Nordeste do Brasil no período de 1984 a 1993 foram estimados visando avaliar a eficiência do programa e traçar novas estratégias. Esta estimativa foi feita a partir dos dados de 59 ensaios regionais de rendimento conduzidos pelas empresas de pesquisa agropecuária do Nordeste, em cooperação com a Embrapa-Centro Nacional de Pesquisa de Arroz e Feijão (CNPAF, Goiânia, GO. O método estatístico utilizado baseia-se em médias ajustadas por modelo linear generalizado. O ganho genético médio estimado foi de 54,9 ± 14,4 kg/ha/ano (0,8%. Nos últimos três anos houve uma tendência de interrupção dos ganhos. A pequena magnitude dos ganhos para produção nesta região podem ser atribuídos ao direcionamento do programa de geração de linhagens da Embrapa para qualidade de grãos e resistência a doenças, às diferenças ambientais existentes entre Goiânia e a Região Nordeste e ao pequeno número de ensaios conduzidos. A genealogia das linhagens foi traçada e verificou-se que os principais ancestrais são os mesmos das cultivares recomendadas. A base genética das linhagens é estreita, o que também pode estar contribuindo para a obtenção de pequenos ganhos genéticos para produtividade.The genetic gains for yield obtained by the breeding program of irrigated rice in the Northeast Region of Brazil from 1984 to 1993 were estimated to evaluate the program efficiency. This estimation was done based on data from 59 regional field trials conducted by the Northeastern farm research institutions in cooperation with Embrapa-Centro Nacional de Pesquisa de Arroz e Feijão (CNPAF, Goiânia, GO, Brazil. The statistical method used was based on adjusted means by generalized linear model. The estimated mean genetic gain was 54.9 ± 14.4 kg/ha-1/yr-1 (0,8%. However, in the last three years, there was a tendency of interrupting

  2. Using Field Data for Energy Efficiency Based on Maintenance and Operational Optimisation. A Step towards PHM in Process Plants

    Directory of Open Access Journals (Sweden)

    Micaela Demichela

    2018-03-01

    Full Text Available Energy saving is an important issue for any industrial sector; in particular, for the process industry, it can help to minimize both energy costs and environmental impact. Maintenance optimization and operational procedures can offer margins to increase energy efficiency in process plants, even if they are seldom explicitly taken into account in the predictive models guiding the energy saving policies. To ensure that the plant achieves the desired performance, maintenance operations and maintenance results should be monitored, and the connection between the inputs and the outcomes of the maintenance process, in terms of total contribution to manufacturing performance, should be explicit. In this study, a model for the energy efficiency analysis was developed, based on cost and benefits balance. It is aimed at supporting the decision making in terms of technical and operational solutions for energy efficiency, through the optimization of maintenance interventions and operational procedures. A case study is here described: the effects on energy efficiency of technical and operational optimization measures for bituminous materials production process equipment. The idea of the Conservation Supply Curve (CSC was used to capture both the cost effectiveness of the measures and the energy efficiency effectiveness. The optimization was thus based on the energy consumption data registered on-site: data collection and modelling of the relevant data were used as a base to implement a prognostic and health management (PHM policy in the company. Based on the results from the analysis, efficiency measures for the industrial case study were proposed, also in relation to maintenance optimization and operating procedures. In the end, the impacts of the implementation of energy saving measures on the performance of the system, in terms of technical and economic feasibility, were demonstrated. The results showed that maintenance optimization could help in reaching

  3. Model-based fault diagnosis framework for effective predictive maintenance / B.B. Akindele

    OpenAIRE

    Akindele, Babatunde Babajide

    2010-01-01

    Predictive maintenance is a proactive maintenance strategy that is aimed at preventing the unexpected failure of equipment through condition monitoring of the health and performance of the equipment. Incessant equipment outage resulting in low availability of production facilities is a major issue in the Nigerian manufacturing environment. Improving equipment availability in Nigeria industry through institution of a full featured predictive maintenance has been suggested by many authors. T...

  4. 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

  5. Application of physical failure models to enable usage and load based maintenance

    NARCIS (Netherlands)

    Tinga, Tiedo

    2010-01-01

    The efficiency of a preventive maintenance process largely depends on the ability to predict the replacement intervals of components. Considering the actual usage of the system increases the accuracy of this prediction. The present paper proposes two new maintenance concepts, that combine the

  6. Integrated Systems Health Management as an Enabler for Condition Based Maintenance and Autonomic Logistics

    Science.gov (United States)

    2015-09-17

    uptime + downtime) definition of Eq. (3), but the definition is slightly different. o OT ST A OT ST TPM TCM TALDT       (4) Where OT is the...operational time, ST is the standby time, TPM is the total preventive maintenance time, TCM is the total corrective maintenance time, and TALDT is the

  7. 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)

  8. Prediction of Combine Economic Life Based on Repair and Maintenance Costs Model

    Directory of Open Access Journals (Sweden)

    A Rohani

    2014-09-01

    Full Text Available Farm machinery managers often need to make complex economic decisions on machinery replacement. Repair and maintenance costs can have significant impacts on this economic decision. The farm manager must be able to predict farm machinery repair and maintenance costs. This study aimed to identify a regression model that can adequately represent the repair and maintenance costs in terms of machine age in cumulative hours of use. The regression model has the ability to predict the repair and maintenance costs for longer time periods. Therefore, it can be used for the estimation of the economic life. The study was conducted using field data collected from 11 John-Deer 955 combine harvesters used in several western provinces of Iran. It was found that power model has a better performance for the prediction of combine repair and maintenance costs. The results showed that the optimum replacement age of John-Deer 955 combine was 54300 cumulative hours.

  9. An example of maintenance program based on a risk analysis; Un exemple de programme de maintenance et etabli sur une analyse des risques

    Energy Technology Data Exchange (ETDEWEB)

    Beringuier, J.P.; Laurens, F.; Notarianni, P.; Reys, P.; Dole, J.M. [Gaz de France (GDF), 75 - Paris (France)

    2000-07-01

    The object of this communication is to present the background of Gaz de France regarding the development, the implementation and the first results of a gas transmission pipelines inspection and rehabilitation program. The development of this program is based on a failure risk analysis. The result of this risk analysis is used to define the order of priority for pipelines inspection. This program allows to allocate maintenance expenses in the most effective way regarding risk reduction, costs and safety goals to be achieved. This program appears to be a modern and flexible tool to promote the safety level of gas transmission pipelines in the eyes of the authorities, the customers and the market regulator. (author)

  10. Signal Analysis of Automotive Engine Spark Ignition System using Case-Based Reasoning (CBR) and Case-based Maintenance (CBM)

    International Nuclear Information System (INIS)

    Huang, H.; Vong, C. M.; Wong, P. K.

    2010-01-01

    With the development of modern technology, modern vehicles adopt electronic control system for injection and ignition. In traditional way, whenever there is any malfunctioning in an automotive engine, an automotive mechanic usually performs a diagnosis in the ignition system of the engine to check any exceptional symptoms. In this paper, we present a case-based reasoning (CBR) approach to help solve human diagnosis problem. Nevertheless, one drawback of CBR system is that the case library will be expanded gradually after repeatedly running the system, which may cause inaccuracy and longer time for the CBR retrieval. To tackle this problem, case-based maintenance (CBM) framework is employed so that the case library of the CBR system will be compressed by clustering to produce a set of representative cases. As a result, the performance (in retrieval accuracy and time) of the whole CBR system can be improved.

  11. Explaining variations in state foster care maintenance rates and the implications for implementing new evidence-based programs

    Science.gov (United States)

    Goldhaber-Fiebert, Jeremy D.; Babiarz, Kimberly S.; Garfield, Rachel L.; Wulczyn, Fred; Landsverk, John; Horwitz, Sarah M.

    2013-01-01

    Background U.S. Child Welfare systems are involved in the lives of millions of children, and total spending exceeds $26 billion annually. Out-of-home foster care is a critical and expensive Child Welfare service, a major component of which is the maintenance rate paid to support housing and caring for a foster child. Maintenance rates vary widely across states and over time, but reasons for this variation are not well understood. As evidence-based programs are disseminated to state Child Welfare systems, it is important to understand what may be the important drivers in the uptake of these practices including state spending on core system areas. Data and methods We assembled a unique, longitudinal, state-level panel dataset (1990–2008) for all 50 states with annual data on foster care maintenance rates and measures of child population in need, poverty, employment, urbanicity, proportion minority, political party control of the state legislature and governorship, federal funding, and lawsuits involving state foster care systems. All monetary values were expressed in per-capita terms and inflation adjusted to 2008 dollars. We used longitudinal panel regressions with robust standard errors and state and year fixed effects to estimate the relationship between state foster care maintenance rates and the other factors in our dataset, lagging all factors by one year to mitigate the possibility that maintenance rates influenced their predictors. Exploratory analyses related maintenance rates to Child Welfare outcomes. Findings State foster care maintenance rates have increased in nominal terms, but in many states, have not kept pace with inflation, leading to lower real rates in 2008 compared to those in 1991 for 54% of states for 2 year-olds, 58% for 9 year-olds, and 65% for 16 year-olds. In multivariate analyses including socioeconomic, demographic, and political factors, monthly foster care maintenance rates declined $15 for each 1% increase in state unemployment and

  12. Crack Growth-Based Predictive Methodology for the Maintenance of the Structural Integrity of Repaired and Nonrepaired Aging Engine Stationary Components

    National Research Council Canada - National Science Library

    Barron, Michael

    1999-01-01

    .... Specifically, the FAA's goal was to develop "Crack Growth-Based Predictive Methodologies for the Maintenance of the Structural Integrity of Repaired and Nonrepaired Aging Engine Stationary Components...

  13. Efficacy of tailored Helicobacter pylori eradication treatment based on clarithromycin susceptibility and maintenance of acid secretion.

    Science.gov (United States)

    Sugimoto, Mitsushige; Uotani, Takahiro; Sahara, Shu; Ichikawa, Hitomi; Yamade, Mihoko; Sugimoto, Ken; Furuta, Takahisa

    2014-08-01

    Insufficient acid inhibition during Helicobacter pylori eradication treatment and bacterial resistance to antibiotics often causes eradication failure. Four times daily dosing (q.i.d.) of a proton-pump inhibitor (PPI) achieves potent acid inhibition, suggesting its potential usefulness as a regimen for eradicating H. pylori infection. Therefore, a tailored eradication regimen based on antibiotic susceptibility and maintenance of acid inhibition should have a high success rate. We investigated the efficacy of such treatment based on clarithromycin (CAM) susceptibility. Using 153 H. pylori-positive Japanese patients, we investigated the efficacy of tailored eradication strategy: (1) Patients infected with CAM-sensitive H. pylori were treated with a PPI (rabeprazole 10 mg q.i.d.), amoxicillin 500 mg q.i.d., and CAM 200 mg b.i.d. (n = 89), and (2) patients infected with CAM-resistant were given the same doses of rabeprazole and amoxicillin and metronidazole 250 mg b.i.d. (n = 64) for 1 week. In the tailored regimen group, the overall eradication rate was 96.7% (95% CI: 92.5-98.9%, 148/153) in the intention-to-treat (ITT) analysis and 97.4% (93.4-99.3%, 148/152) in the PP analysis. The eradication rates for the CAM- and metronidazole-based treatments were similar (95.5% and 98.4%, respectively, p = .400). The tailored treatment achieved a high eradication rate in CYP2C19 rapid metabolizers who were a resistance genotype for PPI treatment (94.3% (86.0-98.4%, 66/70)). A tailored H. pylori eradication regimen based on CAM susceptibility and maintaining acid secretion (rabeprazole 10 mg q.i.d.) is useful because it can achieve an eradication rate exceeding 95%, irrespective of eradication history, thus overcoming differences among CYP2C19 genotypes. © 2014 John Wiley & Sons Ltd.

  14. Polyspectral signal analysis techniques for condition based maintenance of helicopter drive-train system

    Science.gov (United States)

    Hassan Mohammed, Mohammed Ahmed

    For an efficient maintenance of a diverse fleet of air- and rotorcraft, effective condition based maintenance (CBM) must be established based on rotating components monitored vibration signals. In this dissertation, we present theory and applications of polyspectral signal processing techniques for condition monitoring of critical components in the AH-64D helicopter tail rotor drive train system. Currently available vibration-monitoring tools are mostly built around auto- and cross-power spectral analysis which have limited performance in detecting frequency correlations higher than second order. Studying higher order correlations and their Fourier transforms, higher order spectra, provides more information about the vibration signals which helps in building more accurate diagnostic models of the mechanical system. Based on higher order spectral analysis, different signal processing techniques are developed to assess health conditions of different critical rotating-components in the AH-64D helicopter drive-train. Based on cross-bispectrum, quadratic nonlinear transfer function is presented to model second order nonlinearity in a drive-shaft running between the two hanger bearings. Then, quadratic-nonlinearity coupling coefficient between frequency harmonics of the rotating shaft is used as condition metric to study different seeded shaft faults compared to baseline case, namely: shaft misalignment, shaft imbalance, and combination of shaft misalignment and imbalance. The proposed quadratic-nonlinearity metric shows better capabilities in distinguishing the four studied shaft settings than the conventional linear coupling based on cross-power spectrum. We also develop a new concept of Quadratic-Nonlinearity Power-Index spectrum, QNLPI(f), that can be used in signal detection and classification, based on bicoherence spectrum. The proposed QNLPI(f) is derived as a projection of the three-dimensional bicoherence spectrum into two-dimensional spectrum that

  15. Data Base Development of Automobile and Light Truck Maintenance : Volume I. Test and Appendixes A-D

    Science.gov (United States)

    1978-08-01

    The volume describes the development of the life cycle maintenance costs for 212 sales-leading 1970 through 1975 passenger cars and light trucks. These costs provide a data base for the Department of Transportation, which describes the costs for part...

  16. Implementation of Maintenance System Based on Bluetooth Low Energy for Hermetic Inline Amplifiers in CATV Networks

    Directory of Open Access Journals (Sweden)

    Katsuhiro Naito

    2016-02-01

    Full Text Available Cable television (CATV systems generally consist of a headend, trunk cables, distribution cables in the neighborhood, drop cables to a home and in-house wiring, and terminal equipment. Coaxial cables bring a CATV signal to customer premises through a service drop, an overhead or underground cable. Hermetic inline amplifiers are used to amplify the attenuated CATV signal due to propagation loss or splitting the coaxial cable. They are usually installed on utility poles. Therefore, maintenance methods for inline amplifiers on utility poles are important issues in CATV operations. This paper proposes a new maintenance system for inline amplifiers in CATV systems, and develops a prototype implementation. The proposed system consists of an amplifier gain analyser to measure amplification performance of inline amplifiers, a special smartphone application, and a cloud server. The proposed amplifier gain analyser is composed of three functions: a generation of high frequency signals for testing, measurement of the test signal gain, and wireless communication based on Bluetooth Low Energy (BLE. We develop a signal generation circuit for a test signal and a smoothing circuit for converting the high frequency test signals into DC signals. The amplifier gain analyser can evaluate an amplifier gain by comparing an input test signal from the signal generation circuit and an output test signal from an inline amplifier. The measurement function uses Nordic nRF51822, which is a System on Chip (SoC for BLE because Nordic nRF51822 has some AD converter ports for evaluating the DC signals. The smartphone application employs BLE communication function to collect the measured amplifier gain from the amplifier gain analyser. Therefore, we developed a special data collection application for iOS. The data collection application has a central function of BLE, and can find a target peripheral device that is the amplifier gain analyser in this paper. Therefore, technicians

  17. Integrated Instrumentation and Sensor Systems Enabling Condition-Based Maintenance of Aerospace Equipment

    Directory of Open Access Journals (Sweden)

    Richard C. Millar

    2012-01-01

    Full Text Available The objective of the work reported herein was to use a systems engineering approach to guide development of integrated instrumentation/sensor systems (IISS incorporating communications, interconnections, and signal acquisition. These require enhanced suitability and effectiveness for diagnostics and health management of aerospace equipment governed by the principles of Condition-based maintenance (CBM. It is concluded that the systems engineering approach to IISS definition provided clear benefits in identifying overall system requirements and an architectural framework for categorizing and evaluating alternative architectures, relative to a bottom up focus on sensor technology blind to system level user needs. CBM IISS imperatives identified include factors such as tolerance of the bulk of aerospace equipment operational environments, low intrusiveness, rapid reconfiguration, and affordable life cycle costs. The functional features identified include interrogation of the variety of sensor types and interfaces common in aerospace equipment applications over multiplexed communication media with flexibility to allow rapid system reconfiguration to adapt to evolving sensor needs. This implies standardized interfaces at the sensor location (preferably to open standards, reduced wire/connector pin count in harnesses (or their elimination through use of wireless communications.

  18. Factors associated with interest in receiving prison-based methadone maintenance therapy in Malaysia.

    Science.gov (United States)

    Mukherjee, Trena I; Wickersham, Jeffrey A; Desai, Mayur M; Pillai, Veena; Kamarulzaman, Adeeba; Altice, Frederick L

    2016-07-01

    Methadone maintenance therapy (MMT) is crucial for HIV prevention and treatment in people who inject opioids. In Malaysia, a large proportion of the prison population is affected by both HIV and opioid use disorders. This study assessed individual preferences and factors associated with interest in receiving MMT among male prisoners meeting criteria for opioid dependence in Malaysia. A convenience sample of 96 HIV-positive and 104 HIV-negative incarcerated men who met pre-incarceration criteria for opioid dependence was interviewed using a structured questionnaire to examine participant characteristics and attitudes toward MMT. Factors associated with interest in prison-based MMT initiation were identified using logistic regression analysis. Among all participants, 85 (42.5%) were interested in receiving MMT within prison. Independent correlates of interest in prison-based MMT were being previously married (AOR=4.15, 95% CI: 1.15, 15.02), previously incarcerated (AOR=5.68, 95% CI: 1.54, 21.02), depression (AOR=3.66, 95% CI: 1.68, 7.98), daily heroin use in the 30days prior to incarceration (AOR=5.53, 95% CI: 1.65, 18.58), and more favorable attitudes toward MMT (AOR=19.82, 95% CI: 6.07, 64.74). Overall, interest in receiving prison-based MMT was low, and was associated with adverse social, mental health, and drug use consequences. Incarceration provides a unique opportunity to initiate MMT for those who need it, however, optimal scale-up efforts must be systemic and address modifiable factors like improving attitudes toward and motivation for MMT. Informed or shared decision-making tools may be useful in improving expectations and acceptability of MMT. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  19. A prediction method based on grey system theory in equipment condition based maintenance

    International Nuclear Information System (INIS)

    Yan, Shengyuan; Yan, Shengyuan; Zhang, Hongguo; Zhang, Zhijian; Peng, Minjun; Yang, Ming

    2007-01-01

    Grey prediction is a modeling method based on historical or present, known or indefinite information, which can be used for forecasting the development of the eigenvalues of the targeted equipment system and setting up the model by using less information. In this paper, the postulate of grey system theory, which includes the grey generating, the sorts of grey generating and the grey forecasting model, is introduced first. The concrete application process, which includes the grey prediction modeling, grey prediction, error calculation, equal dimension and new information approach, is introduced secondly. Application of a so-called 'Equal Dimension and New Information' (EDNI) technology in grey system theory is adopted in an application case, aiming at improving the accuracy of prediction without increasing the amount of calculation by replacing old data with new ones. The proposed method can provide a new way for solving the problem of eigenvalue data exploding in equal distance effectively, short time interval and real time prediction. The proposed method, which was based on historical or present, known or indefinite information, was verified by the vibration prediction of induced draft fan of a boiler of the Yantai Power Station in China, and the results show that the proposed method based on grey system theory is simple and provides a high accuracy in prediction. So, it is very useful and significant to the controlling and controllable management in safety production. (authors)

  20. Roadside maintenance

    Science.gov (United States)

    2010-01-01

    Roadside Maintenance is a unique element within the highway maintenance program because much of the work involves caring for and/or controlling vegetation. Roadside vegetation, if managed properly, can become more naturally self-sustaining over time ...

  1. e-Learning Content Design for Corrective Maintenance of Toshiba BMC 80.5 based on Knowledge Conversion using SECI Method: A Case Study in Aerospace Company

    Science.gov (United States)

    Permata Shabrina, Ayu; Pramuditya Soesanto, Rayinda; Kurniawati, Amelia; Teguh Kurniawan, Mochamad; Andrawina, Luciana

    2018-03-01

    Knowledge is a combination of experience, value, and information that is based on the intuition that allows an organization to evaluate and combine new information. In an organization, knowledge is not only attached to document but also in routine value creating activities, therefore knowledge is an important asset for the organization. X Corp is a company that focused on manufacturing aerospace components. In carrying out the production process, the company is supported by various machines, one of the machines is Toshiba BMC 80.5. The machine is used occasionally and therefore maintenance activity is needed, especially corrective maintenance. Corrective maintenance is done to make a breakdown machine back to work. Corrective maintenance is done by maintenance operator whose retirement year is close. The long term experience of the maintenance operator needs to be captured by the organization and shared across maintenance division. E-learning is one type of media that can support and assist knowledge sharing. This research purpose is to create the e-learning content for best practice of corrective maintenance activity for Toshiba BMC 80.5 by extracting the knowledge and experience from the operator based on knowledge conversion using SECI method. The knowledge source in this research is a maintenance supervisor and a senior maintenance engineer. From the evaluation of the e-learning content, it is known that the average test score of the respondents who use the e-learning increases from 77.5 to 87.5.

  2. A qualitative phenomenological study: Enhanced, risk-based FAA oversight on part 145 maintenance practices

    Science.gov (United States)

    Sheehan, Bryan G.

    The purpose of this qualitative phenomenological study was to examine the phenomenon of enhanced, risk-based Federal Aviation Administration (FAA) oversight of Part 145 repair stations that performed aircraft maintenance for Part 121 air carriers between 2007 and 2014 in Oklahoma. Specifically, this research was utilized to explore what operational changes have occurred in the domestic Part 145 repair station industry such as variations in management or hiring practices, training, recordkeeping and technical data, inventory and aircraft parts supply-chain logistics, equipment, and facilities. After interviewing 12 managers from Part 145 repair stations in Oklahoma, six major theme codes emerged from the data: quality of oversight before 2007, quality of oversight after 2007, advantages of oversight, disadvantages of oversight, status quo of oversight, and process improvement . Of those six major theme codes, 17 subthemes appeared from the data that were used to explain the phenomenon of enhanced oversight in the Part 145 repair station industry. Forty-two percent of the participants indicated a weak FAA oversight system that has hindered the continuous process improvement program in their repair stations. Some of them were financially burdened after hiring additional full-time quality assurance inspectors to specifically manage enhanced FAA oversight. Notwithstanding, the participants of the study indicated that the FAA must apply its surveillance on a more standardized and consistent basis. They want to see this standardization in how FAA inspectors interpret regulations and practice the same quality of oversight for all repair stations, particularly those that are repeat violators and fail to comply with federal aviation regulations. They believed that when the FAA enforces standardization on a consistent basis, repair stations can become more efficient and safer in the performance of their scope of work for the U.S. commercial air transportation industry.

  3. INCREASING THE AIRCRAFT AIRWORTHINESS MAINTENANCE EFICIENCY BASED ON THE PROJECT MANAGEMENT METHODOLOGY

    Directory of Open Access Journals (Sweden)

    Alexander Abramovich Itskovich

    2017-01-01

    Full Text Available The interrelation between aircraft airworthiness maintenance process (AAMP and the process of project man- agement methodology application is demonstrated.A project portfolio can be formed based on the strategic objectives. The projects with the highest priority are car- ried out, including those which strive to improve the efficiency of AAMP. The proposed approach allows to find the priori- ties of specific projects realization, which are included in the airline project portfolio.The project aimed to improve the efficiency of the AAMP of AN-124-100 of "Volga-Dnepr Airlines" is presented as an example. The statistical data analysis of failures of AN-124-100 fleet has demonstrated that wing components most frequently fail, especially spoiler sections, which are subjected to honeycomb skin mass exfoliation and need to be modi- fied. One of the expected project results should be the К1000 reduction of the wing spoilers not less than for 40 % and, respectively, the plane in total - not less than for 4 %.The work is executed in full compliance with the standards of project management. The passport of the project is given, which contains all the necessary information about the project: its goals, outcomes, results, timelines, action plan, budget and participants. A special attention is paid to the risks of the project, their probability assessment and the actions for overcoming possible consequences. It is shown that the implementation of the project "Introduction of aircraft AN-124-100 spoilers technology modi- fication" allows to improve a number of production and technical efficiency indicators, with material, financial and organi- zational resources optimization.

  4. Genetic Gain in Soybean Crop/ Ganho Genético na Cultura da Soja

    Directory of Open Access Journals (Sweden)

    Ricardo Tadeu de Faria

    2007-07-01

    Full Text Available The selection of genotypes of soybean with high grain yield and high capacity of environment adaptation are the objectives of the genetic improvement programs. To verify if the genetic gain through of the breeding of the soybean crop is being reached it is necessary that, frequently, each improvement program makes an auto-evaluation to verify if there has been effective progress, if a certain culture condition was privileged by the breeding and to correct eventual distortions of goals. To have significant advances the breeding programs have to evaluate their efficiency and it is necessary to use methods that quantify the genetic advances. The possibility of prediction of the gains obtained by selection consists in one of the main contributions for the breeding, becoming possible to guide in a more effective manner the breeding program, to predict the success of the adopted selection method and to determine, scientifically, which techniques can be more efficient.A seleção de genótipos de soja com elevada produtividade de grãos e capacidade de adaptação ambiental é o principal objetivo dos programas de melhoramento genético. Para verificar se o ganho genético por meio de melhoramento da cultura da soja está sendo alcançado é importante que cada programa de melhoramento faça, frequentemente, uma auto-avaliação no sentido de verificar se houve progresso efetivo e se determinada condição de cultivo foi privilegiada pelo melhoramento e corrigir eventuais distorções de metas. Para isso é necessário a utilização de métodos que quantifiquem o avanço genético. A possibilidade de predição dos ganhos obtidos por seleção constitui-se em uma das principais contribuições para o melhoramento. Desta forma, torna-se possível orientar de maneira mais efetiva os programas de melhoramento, predizer o sucesso do esquema de seleção adotado e determinar, de forma científica, quais as técnicas que podem ser mais eficazes.

  5. Examining motivations and barriers for attending maintenance community-based cardiac rehabilitation using the health-belief model.

    Science.gov (United States)

    Horwood, Hayley; Williams, Michael J A; Mandic, Sandra

    2015-10-01

    Reasons for low attendance at maintenance cardiac rehabilitation (CR) programs remain largely unknown. Using the Health Belief Model as a theoretical framework, this study compared the motivations and barriers for attending a community-based CR maintenance program in high attenders (HA), low attenders (LA) and non-attenders (NA) with coronary artery disease (CAD). Forty-four older adults with CAD (70.5% males; age: 72.7±6.9 years; 11 HA, 16 LA and 17 NA) completed questionnaires examining reasons for attending CR: perceived threat (symptoms of CAD; the Revised Illness Perception Questionnaire), perceived benefits (Multi-dimensional Outcomes Expectations for Exercise Scale), perceived barriers (Cardiac Rehabilitation Barriers Scale) and cues to action questionnaire. Sociodemographic characteristics and perceived threat were not different between the groups. Compared to LA and NA, HA perceived greater social and physical (vs NA only) benefits of participation in maintenance CR and had fewer barriers to attending (all phealth concerns and others having heart problems were stronger cues to action for HA versus NA (all p<0.05). Participants perceived greater benefits from attending CR, had fewer barriers and perceived stronger cues to action compared to non-attenders. Promoting CR maintenance programs should emphasise physical and social benefits and provide encouragement. Copyright © 2015 Australian and New Zealand Society of Cardiac and Thoracic Surgeons (ANZSCTS) and the Cardiac Society of Australia and New Zealand (CSANZ). Published by Elsevier B.V. All rights reserved.

  6. 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)

  7. 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

  8. A novel integrated condition-based maintenance and stochastic flexible job shop scheduling problem

    DEFF Research Database (Denmark)

    Rahmati, Seyed Habib A.; Ahmadi, Abbas; Govindan, Kannan

    2018-01-01

    Integrated consideration of production planning and maintenance processes is a real world assumption. Specifically, by improving the monitoring equipment such as various sensors or product-embedded information devices in recent years, joint assessment of these processes is inevitable for enhancin...

  9. Condition-Based Maintenance Strategy for Production Systems Generating Environmental Damage

    Directory of Open Access Journals (Sweden)

    L. Tlili

    2015-01-01

    Full Text Available We consider production systems which generate damage to environment as they get older and degrade. The system is submitted to inspections to assess the generated environmental damage. The inspections can be periodic or nonperiodic. In case an inspection reveals that the environmental degradation level has exceeded the critical level U, the system is considered in an advanced deterioration state and will have generated significant environmental damage. A corrective maintenance action is then performed to renew the system and clean the environment and a penalty has to be paid. In order to prevent such an undesirable situation, a lower threshold level L is considered to trigger a preventive maintenance action to bring back the system to a state as good as new at a lower cost and without paying the penalty. Two inspection policies are considered (periodic and nonperiodic. For each one of them, a mathematical model and a numerical procedure are developed to determine simultaneously the preventive maintenance (PM threshold L∗ and the inspection sequence which minimize the average long-run cost per time unit. Numerical calculations are performed to illustrate the proposed maintenance policies and highlight their main characteristics with respect to relevant input parameters.

  10. Timely condition-based maintenance planning for multi-component systems

    NARCIS (Netherlands)

    Verbert, K.A.J.; De Schutter, B.H.K.; Babuska, R.

    2017-01-01

    Last-minute maintenance planning is often undesirable, as it may cause downtime during operational hours, may require rescheduling of other activities, and does not allow to optimize the management of spare parts, material, and personnel. In spite of the aforementioned drawbacks of last-minute

  11. An Approach to Folksonomy-Based Ontology Maintenance for Learning Environments

    Science.gov (United States)

    Gasevic, D.; Zouaq, Amal; Torniai, Carlo; Jovanovic, J.; Hatala, Marek

    2011-01-01

    Recent research in learning technologies has demonstrated many promising contributions from the use of ontologies and semantic web technologies for the development of advanced learning environments. In spite of those benefits, ontology development and maintenance remain the key research challenges to be solved before ontology-enhanced learning…

  12. Challenges for Risk-based Maintenance Planning for Offshore Wind Turbines

    DEFF Research Database (Denmark)

    Nielsen, Jannie Jessen; Sørensen, John Dalsgaard

    2011-01-01

    This paper concerns the development of a probabilistic model for riskbased maintenance planning for offshore wind turbines. A prior damage model can be combined with data to give an updated estimate of the probability of failure. For indicators, an indicator model is needed, and this paper presents...

  13. Concepts of a software based maintenance efficiency analysis using performance indicators

    International Nuclear Information System (INIS)

    Kirchsteiger, C.; Boeck, H.

    1992-01-01

    The paper briefly summarizes the concepts of a customized computer program in STATGRAPHICS called ''maintenance efficiency analysis (MEA) for safety related systems in nuclear power plants'', which has been developed and submitted to the International Atomic Energy Agency in the form of a research contract. The purpose of this program is to process data from a real plant utilizing advanced statistical procedures (non-parametric methods, multivariate analysis) in order to test several hypotheses related to risk related safety indicators. Plant specific equipment history and maintenance work order data can be analysed by using various statistical procedures in order to be able to estimate safety system related equipment and maintenance process trends. The main results of such an MEA case study are the normalized and scaled trends in the (in)effectiveness of the performance of selected ''important'' safety related systems and their dominant components as well as the detection of the dominant maintenance related causes of their bad (good) equipment performance. (author). 6 refs, 4 figs

  14. Challenges for Risk-based Maintenance Planning for Offshore Wind Turbines

    DEFF Research Database (Denmark)

    Nielsen, Jannie Jessen; Sørensen, John Dalsgaard

    2011-01-01

    This paper concerns the development of a probabilistic model for riskbased maintenance planning for offshore wind turbines. A prior damage model can be combined with data to give an updated estimate of the probability of failure. For indicators, an indicator model is needed, and this paper presents...... how Bayesian networks can be used to learn such a model when past data is available....

  15. Tailoring a Web-Based Weight Maintenance Intervention for Northern Plains American Indian Public University Students

    Science.gov (United States)

    Hemmingson, Kaitlyn; Lucchesi, Roxanne; Droke, Elizabeth; Kattelmann, Kendra K.

    2016-01-01

    Objective: High levels of obesity-related health disparities are common among US American Indian (AI) populations. AI public university students often face unique challenges that may contribute to weight gain and related consequences. Few weight maintenance interventions have been developed that meet the needs of AI public university students. The…

  16. Development of predictive models for estimating warfarin maintenance dose based on genetic and clinical factors.

    Science.gov (United States)

    Yang, Lu; Linder, Mark W

    2013-01-01

    In this chapter, we use calculation of estimated warfarin maintenance dosage as an example to illustrate how to develop a multiple linear regression model to quantify the relationship between several independent variables (e.g., patients' genotype information) and a dependent variable (e.g., measureable clinical outcome).

  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. Identification of National Road Maintenance Needs Based on Strategic Plan of Directorate General of Bina Marga (2015-2019

    Directory of Open Access Journals (Sweden)

    Rizky Ardhiarini

    2016-05-01

    Full Text Available The enhancement of connectivity between the main corridors of the economy in South Sumatera, as a purpose of the Strategic Plan of Directorate General Bina Marga and also an objective of MP3EI, Master Plan for Acceleration and expansion of Indonesia's Economic Development which is an ambitious plan by the Indonesian government to accelerate the realization of becoming a developed country would be able to achieve on the requirement of good condition on performance and pavement. In order to support the optimal condition of the road, the identification of road management was conducted to determine the necessity of road maintenance based on technical conditions and importance level of development of the road traversed. The management program proposed is expected to be used as a baseline in determining the maintenance of the road network in South Sumatera from 2015 until 2019. This research used Multi-criteria Analysis (MCA method, which consists of: (1 road network performance, covering width of roadways, traffic flow, V/C ratio, travel speed and travel time of the vehicle, and (2 pavement condition, with IRI, SDI, and the proportion of good pavement condition as a parameter. Multi-criteria analysis used combined road condition assessment score and importance level of development of the area traversed by. This analysis was conducted from 2015 until 2019. The research concluded that maintenance necessity in 2015 were dominated by routine maintenance (95.86% of the total length, then in 2016 until 2019 the needs were dominated by routine maintenance (near 100% of the total length. As the maintenance applied, a vast amount of total road length fulfilled as an achievement target. The results are follows: (a 100% with width of roadways ≥ 7 meter, (b 97.83% with V/C ratio  60km/hour, (d 17.32% with travel time (TT 95%, (f 90.37% with IRI < 4 m/Km, and (g 91.59 with SDI < 50. Yet with the achievement of 100% of total road length with a

  19. Application of T2 Control Charts and Hidden Markov Models in Condition-Based Maintenance at Thermoelectric Power Plants

    Directory of Open Access Journals (Sweden)

    Emilija Kisić

    2015-01-01

    Full Text Available An innovative approach to condition-based maintenance of coal grinding subsystems at thermoelectric power plants is proposed in the paper. Coal mill grinding tables become worn over time and need to be replaced through time-based maintenance, after a certain number of service hours. At times such replacement is necessary earlier or later than prescribed, depending on the quality of the coal and of the grinding table itself. Considerable financial losses are incurred when the entire coal grinding subsystem is shut down and the grinding table found to not actually require replacement. The only way to determine whether replacement is necessary is to shut down and open the entire subsystem for visual inspection. The proposed algorithm supports condition-based maintenance and involves the application of T2 control charts to distinct acoustic signal parameters in the frequency domain and the construction of Hidden Markov Models whose observations are coded samples from the control charts. In the present research, the acoustic signals were collected by coal mill monitoring at the thermoelectric power plant “Kostolac” in Serbia. The proposed approach provides information about the current condition of the grinding table.

  20. Assessment of skeletal muscle fatigue of road maintenance workers based on heart rate monitoring and myotonometry

    Directory of Open Access Journals (Sweden)

    Kalkis Henrijs

    2006-07-01

    Full Text Available Abstract Objective This research work is dedicated to occupational health problems caused by ergonomic risks. The research object was road building industry, where workers have to work very intensively, have long work hours, are working in forced/constrained work postures and overstrain during the work specific parts of their bodies. The aim of this study was to evaluate the work heaviness degree and to estimate the muscle fatigue of workers after one week work cycle. The study group consisted of 10 road construction and maintenance workers and 10 pavers aged between 20 and 60 years. Methods Physical load were analyzed by measuring heart rate (HR, work postures (OWAS and perceived exertion (RPE. Assessments of the muscles strain and functional state (tone were carried out using myotonometric (MYO measurements. The reliability of the statistical processing of heart rate monitoring and myotonometry data was determined using correlating analysis. Results This study showed that that road construction and repairing works should be considered as a hard work according to average metabolic energy consumption 8.1 ± 1.5 kcal/min; paving, in its turn, was a moderately hard work according to 7.2 ± 1.1 kcal/min. Several muscle tone levels were identified allowing subdivision of workers into three conditional categories basing on muscle tone and fatigue: I – absolute muscle relaxation and ability to relax; II – a state of equilibrium, when muscles are able to adapt to the work load and are partly able to relax; and III – muscle fatigue and increased tone. It was also found out that the increase of muscle tone and fatigue mainly depend on workers physical preparedness and length of service, and less – on their age. Conclusion We have concluded that a complex ergonomic analysis consisting of heart rate monitoring, assessment of compulsive working postures and myotonometry is appropriate to assess the work heaviness degree and can provide prognosis of

  1. Seismic Analysis Code (SAC): Development, porting, and maintenance within a legacy code base

    Science.gov (United States)

    Savage, B.; Snoke, J. A.

    2017-12-01

    The Seismic Analysis Code (SAC) is the result of toil of many developers over almost a 40-year history. Initially a Fortran-based code, it has undergone major transitions in underlying bit size from 16 to 32, in the 1980s, and 32 to 64 in 2009; as well as a change in language from Fortran to C in the late 1990s. Maintenance of SAC, the program and its associated libraries, have tracked changes in hardware and operating systems including the advent of Linux in the early 1990, the emergence and demise of Sun/Solaris, variants of OSX processors (PowerPC and x86), and Windows (Cygwin). Traces of these systems are still visible in source code and associated comments. A major concern while improving and maintaining a routinely used, legacy code is a fear of introducing bugs or inadvertently removing favorite features of long-time users. Prior to 2004, SAC was maintained and distributed by LLNL (Lawrence Livermore National Lab). In that year, the license was transferred from LLNL to IRIS (Incorporated Research Institutions for Seismology), but the license is not open source. However, there have been thousands of downloads a year of the package, either source code or binaries for specific system. Starting in 2004, the co-authors have maintained the SAC package for IRIS. In our updates, we fixed bugs, incorporated newly introduced seismic analysis procedures (such as EVALRESP), added new, accessible features (plotting and parsing), and improved the documentation (now in HTML and PDF formats). Moreover, we have added modern software engineering practices to the development of SAC including use of recent source control systems, high-level tests, and scripted, virtualized environments for rapid testing and building. Finally, a "sac-help" listserv (administered by IRIS) was setup for SAC-related issues and is the primary avenue for users seeking advice and reporting bugs. Attempts are always made to respond to issues and bugs in a timely fashion. For the past thirty-plus years

  2. Risk based maintenance management to reduce the operational costs of wind energy

    Energy Technology Data Exchange (ETDEWEB)

    Rademakers, L.; Braam, H. [Netherlands Energy Research Foundation (ECN), Petten (Netherlands); Robberegt, M.; Katz, P. [Baas and Roost Maintenance Consult, Utrecht (Netherlands)

    2000-07-01

    A Dutch wind turbine manufacturer is presently developing an offshore wind turbine in the MW class. Much more than for onshore turbines, emphasis is put on finding a balance between high reliability, availability and energy output on the one hand and low investment and operational and maintenance (O and M) costs on the other hand. ECN has assisted with the application of reliability analysis techniques for design and for controlling O and M. The paper contains the experiences of ECN with the introduction of these techniques in the daily practice of the manufacturer. The paper focuses on three items: the benefits of performing a risk analysis during the design, the use and collection of operational data, and the development of a maintenance management system. (orig.)

  3. Towards a Risk-based Decision Support for Offshore Wind Turbine Installation and Operation & Maintenance

    DEFF Research Database (Denmark)

    Gintautas, Tomas; Sørensen, John Dalsgaard; Vatne, Sigrid Ringdalen

    2016-01-01

    Costs of operation & maintenance, assembly, transport and installation of offshore wind turbines contribute significantly to the total cost of offshore wind farm. These operations are mostly carried out by specific ships that have to be hired for the operational phase and for duration of installa......Costs of operation & maintenance, assembly, transport and installation of offshore wind turbines contribute significantly to the total cost of offshore wind farm. These operations are mostly carried out by specific ships that have to be hired for the operational phase and for duration...... weather window predictions, potentially reducing cost of offshore wind energy. This paper presents a novel approach to weather window estimation using ensemble weather forecasts and statistical analysis of simulated installation equipment response....

  4. Abacavir-based triple nucleoside regimens for maintenance therapy in patients with HIV.

    Science.gov (United States)

    Cruciani, Mario; Mengoli, Carlo; Serpelloni, Giovanni; Parisi, Saverio G; Malena, Marina; Bosco, Oliviero

    2013-06-05

    Regimen simplification can be defined as a change in established effective therapy to reduce pill burden and dosing frequency, to enhance tolerability, or to decrease specific food and fluid requirements. Many patients on suppressive antiretroviral therapy may be considered candidates for a simplification strategy and, among them, those who have achieved virologic suppression. Several clinical trials have evaluated the efficacy of triple nucleoside combination as a simplification therapy in patients who achieved virologic suppression The aim of this review is to combine randomised, controlled trials to examine whether in patients with undetectable viraemia on a Protease inhibitor (PI) based regimen simplification treatment with abacavir (ABC)-based triple-nucleoside combinations has similar rates of efficacy and tolerability compared with a PI regimen or simplification with a NNRTIs (efavirenz-EFV- or nevirapine-NVP) containing regimen. Studies were included if they had at least two of the three interventions, including one 3NRTI arm. Electronic databases and conference proceedings were searched (1996-2012) with relevant search terms without limits to language. Randomised controlled trials (RCTs) only are included in this review. Patients population is represented by HIV-infected adult patients treated with a PI-containing regimen (PI or boosted PI),  with undetectable viral load. Patients on a PI-containing regimen had three possibilities: continue the PI regimen or switch to a simplification maintenance regimen, including switch to a NNRTI (EFV or NVP) containing regimen, or switch to a triple-NRTI regimen (ABC-zidovudine-lamivudine) The primary outcomes were: proportion of patients discontinuing or switching antiretroviral therapy due to virologic failure or to adverse events; death (all cause) and AIDS defining illness; occurrence of myocardial infarction and cardiovascular disease. Secondary outcomes  were: proportion of patients maintaining an undetectable

  5. COMPARISON OF NON-COLIFORM BACTERIA IN BALI CATTLE FAECES BASED ON LEVEL OF MATURITY AND MAINTENANCE PATTERN

    Directory of Open Access Journals (Sweden)

    Kadek Andre Sulaksana

    2017-08-01

    Full Text Available This study aim was to determine the effect of maintenance type and maturity level of bali cattle to the total of non coliform bacteria in bali cattle. A total of 24 samples of bali cattle’s feces were used. This study was a Factorial 2 x 3 of group-randomised design, contained of two type maintenance (TPA Suwung and Sobangan and three levels of cattle maturity (calves, heifers, and adult. The groups were based on time sampling. The data then analyzed using Analysis of Variance Test and continued by using Least Significant Different test. The results showed that the amount of non-coliform bacteria in adult bali cattle feces were higher then heifers and calves. Total of non coliform bacteria in bali cattle in  landfill was higher then the cattle that reared in captivity in Bali Cattle Breeding Center, the Sobangan village of Mengwi Badung regency.

  6. Automating Contextualized Maintenance Documentation

    NARCIS (Netherlands)

    Koornneef, H.; Verhagen, W.J.C.; Curran, Ricky; Borsato, M.; Wognum, N.; Peruzzini, M.; Stjepandić, J.; Verhagen, W.J.C.

    2016-01-01

    Currently, task support information in aircraft maintenance is mostly provided using paper-based solutions, which are burdensome, slow and prone to error. Aircraft maintenance documentation contains vast amounts of information irrelevant for the task at hand and even for the simplest tasks multiple

  7. A INFLUÊNCIA DA TERMOTERAPIA NO GANHO DE FLEXIBILIDADE DOS MÚSCULOS ISQUIOTIBIAIS

    Directory of Open Access Journals (Sweden)

    José Herivelton Cardoso de Andrade Filho

    Full Text Available RESUMO Introdução: A flexibilidade muscular é descrita como a capacidade do músculo realizar a extensão de suas fibras, influenciando a mobilidade articular. A diatermia aplicada à musculatura prepara o corpo para atividades físicas, por acelerar o metabolismo das fibras musculares e diminuir a resistência intramuscular, aumentando assim a variedade de movimento e a eficiência mecânica. A crioterapia tem diversas funções fisiológicas quando aplicada ao corpo humano, as quais, em conjunto, propiciam o relaxamento muscular. Objetivo: Avaliar o comportamento da flexibilidade dos músculos isquiotibiais frente à aplicação de alongamento passivo associado a termoterapias quente e fria. Métodos: Este estudo foi composto de 24 voluntários, de ambos os sexos, distribuídos aleatoriamente em três grupos, sendo eles: grupo alongamento passivo (G1, grupo crioterapia precedendo alongamento passivo (G2 e grupo diatermia precedendo alongamento passivo (G3. Os voluntários foram submetidos a avaliações de amplitude de movimento através da goniometria da flexão de quadril com o joelho estendido, sendo uma avaliação inicial realizada antes de iniciar o protocolo e reavaliações ao final de cada uma das quatro semanas de intervenção. Resultados: Verificou-se aumento significativo da flexão de quadril no G2 e G3 com relação ao G1. Não houve diferença estatística entre G2 e G3. Conclusão: O uso da diatermia, assim como da crioterapia, associado ao alongamento passivo é favorável para o ganho de flexibilidade muscular e, consequentemente, de amplitude de movimento em jovens saudáveis.

  8. Avaliação do consumo e ganho de peso de novilhos em pastejo rotacionado de capim-elefante (Pennisetum purpureum, Schum. cv. Napier, na estação chuvosa Evaluation of intake and weight gain of steers in rotacional grazing of elephantgrass (Pennisetum purpureum, Schum. cv. Napier, during the rainy season

    Directory of Open Access Journals (Sweden)

    Eleonora D'Avila Erbesdobler

    2002-09-01

    Full Text Available A pesquisa foi conduzida na Fazenda Experimental da EPAMIG-Leopoldina, MG, onde foram avaliados o consumo de capim-elefante, a efetividade da limitação do tempo de pastejo a quatro horas diárias, para manter o consumo próximo à mantença e o ganho de peso de 36 novilhos ¾ Gir-Holandês, em cinco períodos sucessivos de 36 dias, na estação chuvosa. Os tratamentos foram: livre acesso ao pasto (pastejo irrestrito e pastejo restrito. A disponibilidade de matéria verde seca do capim-elefante nos cinco períodos variou de 4,0 a 7,8 kg/100 kg PV. Os animais com livre acesso ao pasto consumiram o equivalente a 1,61 vezes o dos animais de pastejo restrito e tiveram ganho de peso de corpo vazio médio diário de 516,4 g, com um ganho estimado de 432,5 kg por hectare, estando dentro da faixa de ganho de peso verificada para capim-elefante no Brasil. O consumo de energia metabolizável por unidade de tamanho metabólico manteve-se estável nos três primeiros períodos, elevando-se nos dois últimos períodos, em que ocorreram os maiores ganhos de peso dos animais. Quatro horas diárias de pastejo garantiram consumo próximo à mantença.The research was conducted in the experimental farm of the EPAMIG-Leopoldina, MG, to evaluate intake of elephantgrass, the effectiveness of limiting grazing time to four daily hours for keeping intake close to maintenance level, and the weight gain of thirty-six steers during five successive periods of thirty-six days, during the rainy season. The treatments were: free access to pasture (unlimited grazing and restricted grazing. The availability of green dry matter varied from 4.0 to 7.8 kg/100kg LW. The average daily weight gain of animals with free access to pasture was 516.5 g and their dry matter intake corresponded to 1.61 times that from the restricted grazing ones. The estimated gain per hectare was 423.5 kg, which is within the range reported for elephantgrass in Brasil. Metabolizable energy intake, per

  9. Decommissioning and Dismantling of the Floating Maintenance Base 'Lepse' - 13316

    Energy Technology Data Exchange (ETDEWEB)

    Field, D.; Mizen, K. [Nuvia Limited (United Kingdom)

    2013-07-01

    The Lepse was built in Russia in 1934 and commissioned as a dry cargo ship. In 1961 she was re-equipped for use as a nuclear service ship (NSS), specifically a floating maintenance base (FMB), to support the operation of the civilian nuclear fleet (ice-breakers) of the USSR. In 1988 Lepse was taken out of service and in 1990 she was re-classified as a 'berth connected ship', located at a berth near the port of Murmansk under the ownership of Federal State Unitary Enterprise (FSUE) Atomflot. Lepse has special storage facilities for spent nuclear fuel assemblies (SFA) that have been used to store several hundred SFAs for nearly 40 years. High and intermediate-level liquid radioactive waste (LRW) is also present in the spent nuclear fuel assembly storage channels, in special tanks and also in the SFA cooling circuit. Many of the SFAs stored in Lepse are classified as damaged and cannot be removed using standard procedures. The removal of the SFA and LRW from the Lepse storage facilities is a hazardous task and requires specially designed tools, equipment and an infrastructure in which these can be deployed safely. Lepse is a significant environmental hazard in the North West of Russia. Storing spent nuclear fuel and high-level liquid radioactive waste on board Lepse in the current conditions is not acceptable with respect to Russian Federation health, safety and environmental standards and with international best practice. The approved concept design for the removal of the SFA and LRW and dismantling of Lepse requires that the ship be transported to Nerpa shipyard where specialist infrastructure will be constructed and equipment installed. One of the main complexities of the Project lies within the number of interested stakeholders involved in the Project. The Lepse project has been high focus on the international stage for many years with previous international efforts failing to make significant progress towards the objective of decommissioning Lepse. The

  10. The design and use of proficiency based BWR reactor maintenance and refuelling training mockups

    International Nuclear Information System (INIS)

    Ford, G.J.

    1996-01-01

    The purpose of this paper is to describe the ABB experience with the design and use of boiling water reactor training facilities. The training programs were developed and implemented in cooperation with the nuclear utilities. ABB operates two facilities, the ABB ATOM Light Water Reactor Service Center located in Vasteras, Sweden, and the ABB Combustion Engineering Nuclear Operations BWR Training Center located in Chattanooga, Tennessee, USA. The focus of the training centers are reactor maintenance and refueling activities plus the capability to develop and qualify tools, procedures and repair techniques

  11. Exigências Líquidas de Aminoácidos para Ganho de Peso de Nelores Não-Castrados Net Amino Acids Requirements for Weight Gain of Nellore Bulls

    Directory of Open Access Journals (Sweden)

    Fabiano Ferreira da Silva

    2002-01-01

    Full Text Available Foram utilizados 40 novilhos Nelore inteiros, com peso vivo médio inicial de 240 kg, sendo quatro novilhos de referência, quatro alimentados para mantença e o restante distribuído em oito tratamentos, com quatro diferentes níveis de concentrado nas dietas (20; 40; 60 e 80% e dois níveis de proteína bruta (PB (15 e 18%. A fase de recria foi avaliada até 360 kg de peso vivo e a fase de engorda, até 450 kg de peso vivo. O volumoso utilizado foi feno de capim Tyfton (Cynodon dactylon. Após o abate, todas as partes do corpo do animal foram pesadas e amostradas. As amostras foram liofilizadas para determinação de matéria seca, pré-desengorduradas com éter e, posteriormente, moídas e determinados os teores de aminoácidos. As exigências líquidas de aminoácidos para ganho de peso foram calculadas segundo o método fatorial, no qual o ganho de proteína foi multiplicado pela composição aminoacídica do corpo vazio. A exigência líquida de aminoácidos para mantença foi estimada. A soma das exigências metabolizável para mantença e ganho compôs a exigência total de aminoácidos metabolizáveis. As exigências líquidas para ganho de aminoácidos diminuíram com o aumento do peso vivo do animal. A exigência total de aminoácidos metabolizáveis, expressos em % do total de aminoácidos essenciais, não variou muito com o aumento do peso vivo, obtendo-se valores médios de 2,66; 15,11; 6,09; 8,64; 9,26; 18,48; 8,33; 12,01; e 19,41 para metionina, lisina, histidina, fenilalanina, treonina, leucina, isoleucina, valina e arginina, respectivamente.Forty Nellore bulls, with 240 kg initial live weight (LW, were used. Four were reference bulls, four were fed for maintenance, and the remaining were allotted to eight treatments, with four different concentrate levels in the diets (20, 40, 60 and 80% and two levels of crude protein (CP (15 and 18%. The growing phase was evaluated up to 360 kg of LW and the fattening phase, up to 450 kg of

  12. Selection of optimum maintenance strategies based on a fuzzy analytic hierarchy process

    Directory of Open Access Journals (Sweden)

    Aida Azizi

    2014-05-01

    Full Text Available This paper presents an empirical investigation to rank different factors influencing on maintenance strategies on Iranian oil terminals’ company. The study determines four main factors, production quality, reliability, cost and safety. Using fuzzy analytical process, the study determines various factors associated with each main factor and ranks them by performing pair-wise comparisons. The results indicate that reliability ranks first (0.255, followed by production quality (0.252, cost (0.25 and safety (0.244. In terms of reliability, the best utilization of resources is number one priority followed by increase access to maintenance tools, reduction in production interruption are among the most important issues. In terms of production quality, reduction in system failure as well as reworks is the most important factors followed by customer satisfaction and defects. In terms of cost items, ease of access to accessories and consulting are important factors followed by necessary software, hardware and training programs. Finally, in terms of safety factors, external, internal and employee services are the most important issues, which are needed to be considered.

  13. A framework for the design of a voice-activated, intelligent, and hypermedia-based aircraft maintenance manual

    Science.gov (United States)

    Patankar, Manoj Shashikant

    Federal Aviation Regulations require Aviation Maintenance Technicians (AMTs) to refer to approved maintenance manuals when performing maintenance on airworthy aircraft. Because these manuals are paper-based, larger the size of the aircraft, more cumbersome are the manuals. Federal Aviation Administration (FAA) recognized the difficulties associated with the use of large manuals and conducted studies on the use of electronic media as an alternative to the traditional paper format. However, these techniques do not employ any artificial intelligence technologies and the user interface is limited to either a keyboard or a stylus pen. The primary emphasis of this research was to design a generic framework that would allow future development of voice-activated, intelligent, and hypermedia-based aircraft maintenance manuals. A prototype (VIHAMS-Voice-activated, Intelligent, and Hypermedia-based Aircraft Maintenance System) was developed, as a secondary emphasis, using the design and development techniques that evolved from this research. An evolutionary software design approach was used to design the proposed framework and the structured rapid prototyping technique was used to produce the VIHAMS prototype. VoiceAssist by Creative Labs was used to provide the voice interface so that the users (AMTs) could keep their hands free to work on the aircraft while maintaining complete control over the computer through discrete voice commands. KnowledgePro for Windows sp{TM}, an expert system shell, provided "intelligence" to the prototype. As a result of this intelligence, the system provided expert guidance to the user. The core information contained in conventional manuals was available in a hypermedia format. The prototype's operating hardware included a notebook computer with a fully functional audio system. An external microphone and the built-in speaker served as the input and output devices (along with the color monitor), respectively. Federal Aviation Administration

  14. Context-Dependent Prognostics and Health Assessment: A Condition-Based Maintenance Approach That Supports Mission Compliance

    Energy Technology Data Exchange (ETDEWEB)

    Allgood, G.O.; Kercel, S.W.

    1999-04-19

    In today's manufacturing environment, plants, systems, and equipment are being asked to perform at levels not thought possible a decade ago. The intent is to improve process operations and equipment reliability, availability, and maintainability without costly upgrades. Of course these gains must be achieved without impacting operational performance. Downsizing is also taking its toll on operations. Loss of personnel, particularly those who represent the corporate history, is depleting US industries of their valuable experiential base which has been relied on so heavily in the past. These realizations are causing companies to rethink their condition-based maintenance policies by moving away from reacting to equipment problems to taking a proactive approach by anticipating needs based on market and customer requirements. This paper describes a different approach to condition-based maintenance-context-dependent prognostics and health assessment. This diagnostic capability is developed around a context-dependent model that provides a capability to anticipate impending failures and determine machine performance over a protracted period of time. This prognostic capability links operational requirements to an economic performance model. In this context, a system may provide 100% operability with less than 100% functionality. This paradigm is used to facilitate optimal logistic supply and support.

  15. A Novel Idea for Optimizing Condition-Based Maintenance Using Genetic Algorithms and Continuous Event Simulation Techniques

    Directory of Open Access Journals (Sweden)

    Mansoor Ahmed Siddiqui

    2017-01-01

    Full Text Available Effective maintenance strategies are of utmost significance for system engineering due to their direct linkage with financial aspects and safety of the plants’ operation. At a point where the state of a system, for instance, level of its deterioration, can be constantly observed, a strategy based on condition-based maintenance (CBM may be affected; wherein upkeep of the system is done progressively on the premise of monitored state of the system. In this article, a multicomponent framework is considered that is continuously kept under observation. In order to decide an optimal deterioration stage for the said system, Genetic Algorithm (GA technique has been utilized that figures out when its preventive maintenance should be carried out. The system is configured into a multiobjective problem that is aimed at optimizing the two desired objectives, namely, profitability and accessibility. For the sake of reality, a prognostic model portraying the advancements of deteriorating system has been employed that will be based on utilization of continuous event simulation techniques. In this regard, Monte Carlo (MC simulation has been shortlisted as it can take into account a wide range of probable options that can help in reducing uncertainty. The inherent benefits proffered by the said simulation technique are fully utilized to display various elements of a deteriorating system working under stressed environment. The proposed synergic model (GA and MC is considered to be more effective due to the employment of “drop-by-drop approach” that permits successful drive of the related search process with regard to the best optimal solutions.

  16. Two Innovative Steps for Training on Maintenance: 'VIRMAN' Spanish Project based on Virtual Reality 'STARMATE' European Project based on Augmented Reality

    International Nuclear Information System (INIS)

    Gonzalez Anez, Francisco

    2002-01-01

    This paper presents two development projects (STARMATE and VIRMAN) focused on supporting training on maintenance. Both projects aim at specifying, designing, developing, and demonstrating prototypes allowing computer guided maintenance of complex mechanical elements using Augmented and Virtual Reality techniques. VIRMAN is a Spanish development project. The objective is to create a computer tool for maintenance training course elaborations and training delivery based on 3D virtual reality models of complex components. The training delivery includes 3D record displays on maintenance procedures with all complementary information for intervention understanding. Users are requested to perform the maintenance intervention trying to follow up the procedure. Users can be evaluated about the level of knowledge achieved. Instructors can check the evaluation records left during the training sessions. VIRMAN is simple software supported by a regular computer and can be used in an Internet framework. STARMATE is a forward step in the area of virtual reality. STARMATE is a European Commission project in the frame of 'Information Societies Technologies'. A consortium of five companies and one research institute shares their expertise in this new technology. STARMATE provides two main functionalities (1) user assistance for achieving assembly/de-assembly and following maintenance procedures, and (2) workforce training. The project relies on Augmented Reality techniques, which is a growing area in Virtual Reality research. The idea of Augmented Reality is to combine a real scene, viewed by the user, with a virtual scene, generated by a computer, augmenting the reality with additional information. The user interface is see-through goggles, headphones, microphone and an optical tracking system. All these devices are integrated in a helmet connected with two regular computers. The user has his hands free for performing the maintenance intervention and he can navigate in the virtual

  17. Physical activity maintenance among Spanish-speaking Latinas in a randomized controlled trial of an Internet-based intervention.

    Science.gov (United States)

    Hartman, Sheri J; Dunsiger, Shira I; Bock, Beth C; Larsen, Britta A; Linke, Sarah; Pekmezi, Dori; Marquez, Becky; Gans, Kim M; Mendoza-Vasconez, Andrea S; Marcus, Bess H

    2017-06-01

    Spanish-speaking Latinas have some of the lowest rates of meeting physical activity guidelines in the U.S. and are at high risk for many related chronic diseases. The purpose of the current study was to examine the maintenance of a culturally and individually-tailored Internet-based physical activity intervention for Spanish-speaking Latinas. Inactive Latinas (N  =  205) were randomly assigned to a 6-month Tailored Physical Activity Internet Intervention or a Wellness Contact Control Internet Group, with a 6-month follow-up. Maintenance was measured by assessing group differences in minutes per week of self-reported and accelerometer measured moderate to vigorous physical activity (MVPA) at 12 months after baseline and changes in MVPA between the end of the active intervention (month 6) and the end of the study (month 12). Potential moderators of the intervention were also examined. Data were collected between 2011 and 2014, and were analyzed in 2015 at the University of California, San Diego. The Intervention Group engaged in significantly more minutes of MVPA per week than the Control Group at the end of the maintenance period for both self-reported (mean diff. = 30.68, SE = 11.27, p = .007) and accelerometer measured (mean diff. = 11.47, SE = 3.19, p = .01) MVPA. There were no significant between- or within-group changes in MVPA from month 6 to 12. Greater intervention effects were seen for those with lower BMI (BMI × intervention = -6.67, SE = 2.88, p = .02) and lower perceived places to walk to in their neighborhood (access × intervention = -43.25, SE = 19.07, p = .02), with a trend for less family support (social support × intervention = -3.49, SE = 2.05, p = .08). Acculturation, health literacy, and physical activity related psychosocial variables were not significant moderators of the intervention effect during the maintenance period. Findings from the current study support the efficacy of an Internet

  18. Material degradation analysis and maintenance decisions based on material condition monitoring during in-service inspections

    International Nuclear Information System (INIS)

    Yacout, A.M.; Orechwa, Y.

    1996-03-01

    The degradation of the material in critical components is shown to be an effective measure which can be used to compute the risk adjusted economic penalty associated with different maintenance decisions. The approach of estimating the probability, with confidence interval, of the time that a prescribed degradation level is exceeded is shown to be practical, as demonstrated in the analysis of irradiated fuel cladding. The methodology for the estimation of the probability is predicated on the existence of a parsimonious and robust mixed-effects model of the evolution of the degradation. This model, in general, relates measured surrogates of the degradation level to computed or measured variables, which characterize the environment during the operating history of the component. We propose and demonstrate the efficacy of using an artificial neural network, constructed via a genetic supervisor, as an aid in developing the requisite mixed-effects model and testing its continued validity as new data are obtained

  19. Tampering by office-based methadone maintenance patients with methadone take home privileges: a pilot study

    Directory of Open Access Journals (Sweden)

    Frank Nathan

    2007-10-01

    Full Text Available Abstract Methadone Maintenance Treatment (MMT is among the most widely studied treatments for opiate dependence with proven benefits for patients and society. When misused, however, methadone can also be lethal. The issue of methadone diversion is a major concern for all MMT programs. A potential source for such diversion is from those MMT patients who receive daily take home methadone doses. Using a reverse phase high performance liquid chromatography method, seven of the nine patients who were randomly selected to have all of their remaining methadone take home doses (within a 24 hour period analyzed, returned lower than expected quantities of methadone. This finding suggests the possibility that such patients may have tampered with their daily take home doses. Larger prospective observational studies are clearly needed to test the supposition of this pilot study.

  20. 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

  1. Condition-based maintenance. With application on a heat exchanger and a pump; Tillstaandsbaserat underhaall. Med applikation paa en vaermevaexlare och en pump

    Energy Technology Data Exchange (ETDEWEB)

    Raaberg, Martin; Slaetteke, Ola

    2012-02-15

    Regular maintenance is required to extend the life of a plant's components and maintain optimum operation. Unnecessary outages from maintenance may inflict large monetary losses. Therefore, a cost-effective maintenance system should be condition-based rather than time-based. The optimal maintenance scheme requires a process model and a forecast of the operation conditions of this model. At least one of the model parameters should be affected by the maintenance. To determine the actual status of the plant, the model parameters should be estimated. This requires an analysis of available data to detect degradation of the critical components performance. Base load plants usually operate at maximum production or as close to maximum as possible at stabile conditions during long periods. Since the operating time is long and usually at high load in base load plants, advanced control systems and maintenance planning is most profitable in such plants. Advanced control and process optimization requires dynamic process models. Due to the long operating time of a base load plant, it is natural that its process characteristics change, such as wear and fouling. This means that models must be adapted continuously in order to generate a good approximation and thus a good basis for control and optimization. The problem is that the stable operation condition of a base load plant prevents a good estimate of model parameters through the lack of excitation of the process

  2. Priority of road maintenance management based on halda reading range on NAASRA method

    Science.gov (United States)

    Surbakti, M.; Doan, A.

    2018-02-01

    The road pavement, constantly experiencing stress-strain due to traffic load through it, can cause damage to the pavement. Therefore, early detection and repair of the damage will be able to prevent more severe damage that can develop into pavement failure. A road condition survey is one of the earliest attempts to detect the initial damage of a pavement. In this case the driving comfort is the most important part for the driver in assessing road conditions that are affected by the level of road surface roughness. To determine the level of roughness of the road, one of the methods developed is the measurement using the NAASRA method. In this method the roughness of the road is an accumulation of the average unevenness of the road, with the general setting on halda of 100 m. However, with this 100-meter setting, in some places the final value of the roughness value is too large or too small so that it will result in the priority of the road maintenance. This is what underlies roughness research by comparing halda settings at 50 m and 200 m different from the general settings above.This study uses the International Roughness Index (IRI) method in determining the level of road stability concerning driving discomfort. IRI score obtained from direct survey in field by using Roughometer-NAASRA.The final result shows that there is a significant difference between the reading of halda which is set at 100 m reading with halda set with 50 and 200 meter readings. This may lead to differences in handling priorities, which may impact on the sustainability of road network maintenance management (Sustainaible Road Management)

  3. 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...

  4. Fissuras labiopalatinas, ganho de peso e cirurgias: leite materno versus fórmulas lácteas

    OpenAIRE

    Marcos Roberto Tovani-Palone

    2015-01-01

    As fissuras labiopalatinas são as anomalias craniofaciais mais comuns na espécie humana. Por sua vez, com o propósito de ganho de peso corporal necessário para realização das cirurgias reabilitadoras, uma alternativa rotineiramente utilizada para crianças com fissuras consiste no uso de fórmulas lácteas industrializadas, como um substituto do leite materno ou mesmo uma suplementação alimentar. Contudo, é imprescindível a conscientização das mães e demais cuidadores desse grupo de crianças sob...

  5. Thyroid hormone role on cerebellar development and maintenance: a perspective based on transgenic mouse models

    Directory of Open Access Journals (Sweden)

    Larissa Costa Faustino

    2014-05-01

    Full Text Available Cerebellum development is sensitive to thyroid hormone (TH levels, as THs regulate neuronal migration, differentiation and myelination. Most effects of THs are mediated by the TH receptor (TR isoforms TRb1, TRb2 and TRa1. Studies aimed at identifying TH target genes during cerebellum development have only achieved partial success, as some of these genes do not possess classical TH-responsive elements, and those that do are likely to be temporally and spatially regulated by THs. THs may also affect neurodevelopment by regulating transcription factors that control particular groups of genes. Furthermore, TH action can also be affected by TH transport, which is mediated mainly by monocarboxylate transporter family members. Studies involving transgenic animal models and genome-wide expression analyses have helped to address the unanswered questions regarding the role of TH in cerebellar development. Recently, a growing body of evidence has begun to clarify the molecular, cellular and functional aspects of THs in the developing cerebellum. This review describes the current findings concerning the effects of THs on cerebellar development and maintenance as well as advances in the genetic animal models used in this field.

  6. Building a new predictor for multiple linear regression technique-based corrective maintenance turnaround time.

    Science.gov (United States)

    Cruz, Antonio M; Barr, Cameron; Puñales-Pozo, Elsa

    2008-01-01

    This research's main goals were to build a predictor for a turnaround time (TAT) indicator for estimating its values and use a numerical clustering technique for finding possible causes of undesirable TAT values. The following stages were used: domain understanding, data characterisation and sample reduction and insight characterisation. Building the TAT indicator multiple linear regression predictor and clustering techniques were used for improving corrective maintenance task efficiency in a clinical engineering department (CED). The indicator being studied was turnaround time (TAT). Multiple linear regression was used for building a predictive TAT value model. The variables contributing to such model were clinical engineering department response time (CE(rt), 0.415 positive coefficient), stock service response time (Stock(rt), 0.734 positive coefficient), priority level (0.21 positive coefficient) and service time (0.06 positive coefficient). The regression process showed heavy reliance on Stock(rt), CE(rt) and priority, in that order. Clustering techniques revealed the main causes of high TAT values. This examination has provided a means for analysing current technical service quality and effectiveness. In doing so, it has demonstrated a process for identifying areas and methods of improvement and a model against which to analyse these methods' effectiveness.

  7. A fuzzy knowledge based method for maintenance planning in a power system

    International Nuclear Information System (INIS)

    Sergaki, Amalia; Kalaitzakis, Kostas

    2002-01-01

    The inspection planning in electric power industry is used to assess the safety and reliability of system components and to increase the ability of failure situation identification before it actually occurs. It reflects the implications of the available information on the operational and maintenance history of the system. The output is a ranked list of components, with the most critical ones at the top, which indicates the selection of the components to be inspected. In this paper, we demonstrate the use of a fuzzy relational database model for manipulating the data required for the criticality component ranking in thermal power systems inspection planning, incorporating criteria concerning aspects of safety and reliability, economy, variable operational conditions and environmental impacts. Often, qualitative thresholds and linguistic terms are used for the component criticality analysis. Fuzzy linguistic terms for criteria definitions along with fuzzy inference mechanisms allow the exploitation of the operators' expertise. The proposed database model ensures the representation and handling of the aforementioned fuzzy information and additionally offers to the user the functionality for specifying the precision degree by which the conditions involved in a query are satisfied. In order to illustrate the behavior of the model, a case study is given using real inspection data

  8. An operator training simulator based on interactive virtual teleoperation: nuclear facilities maintenance applications

    International Nuclear Information System (INIS)

    Kim, Ki Ho; Kim, Seung Ho

    1997-01-01

    Remote manipulation in nuclear hazardous environment is very often complex and difficult to operate and requires excessively careful preparation. Remote slave manipulators for unstructured work are manually controlled by a human operator. Small errors made by the operator via the master manipulator during operation can cause the slave to be surffered from excessive forces and result in considerable damages to the slave iteself and its environment. In this paper, we present a prototype of an operator training simulator for use in nuclear facilities maintenance applications, as part of the ongoing Nuclear Robotics Development Program at Korea Atomic Energy Research Institute (KAERI). The operator training simulator provides a means by which, in virtual task simulation, the operator can try out and train for expected remote tasks that the real slave manipulator will perform in advance. The operator interacts with both the virtual slave and task environment through the real master. Virtual interaction force feedback is provided to the operator. We also describe a man-in-the loop control scheme to realize bilateral force reflection in virtual teleoperation

  9. 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...... 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...

  10. Computational framework for risk-based planning of inspections, maintenance, and condition monitoring using discrete Bayesian networks

    DEFF Research Database (Denmark)

    Nielsen, Jannie Sønderkær; Sørensen, John Dalsgaard

    2018-01-01

    This paper presents a computational framework for risk-based planning of inspections and repairs for deteriorating components. Two distinct types of decision rules are used to model decisions: simple decision rules that depend on constants or observed variables (e.g. inspection outcome...... expecte d life-cycle costs. For advanced decision rules, simulations are performed to estimate the expected costs, and dBNs are used within the simulations for decision-making. Information from inspections and condition monitoring are included if available. An example in the paper demonstrates...... the framework and the implemented strategies and decision rules, including various types of condition-based maintenance. The strategies using advanced decision rules lead to reduced costs compared to the simple decision rules when condition monitoring is applied, and the value of condition monitoring...

  11. Employment-Based Abstinence Reinforcement as a Maintenance Intervention for the Treatment of Cocaine Dependence: A Randomized Controlled Trial

    Science.gov (United States)

    DeFulio, Anthony; Donlin, Wendy D.; Wong, Conrad J.; Silverman, Kenneth

    2009-01-01

    Context: Due to the chronic nature of cocaine dependence, long-term maintenance treatments may be required to sustain abstinence. Abstinence reinforcement is among the most effective means of initiating cocaine abstinence. Practical and effective means of maintaining abstinence reinforcement programs over time are needed. Objective: Determine whether employment-based abstinence reinforcement can be an effective long-term maintenance intervention for cocaine dependence. Design: Participants (N=128) were enrolled in a 6-month job skills training and abstinence initiation program. Participants who initiated abstinence, attended regularly, and developed needed job skills during the first six months were hired as operators in a data entry business and randomly assigned to an employment only (Control, n = 24) or abstinence-contingent employment (n = 27) group. Setting: A nonprofit data entry business. Participants: Unemployed welfare recipients who persistently used cocaine while enrolled in methadone treatment in Baltimore. Intervention: Abstinence-contingent employment participants received one year of employment-based contingency management, in which access to employment was contingent on provision drug-free urine samples under routine and then random drug testing. If a participant provided drug-positive urine or failed to provide a mandatory sample, then that participant received a temporary reduction in pay and could not work until urinalysis confirmed recent abstinence. Main Outcome Measure: Cocaine-negative urine samples at monthly assessments across one year of employment. Results: During the one-year of employment, abstinence-contingent employment participants provided significantly more cocaine-negative urine samples than employment only participants (79.3% and 50.7%, respectively; p = 0.004, OR = 3.73, 95% CI = 1.60 – 8.69). Conclusions: Employment-based abstinence reinforcement that includes random drug testing is effective as a long-term maintenance

  12. Reducing costs by clustering maintenance activities for multiple critical units

    NARCIS (Netherlands)

    de Jonge, Bram; Klingenberg, Warse; Teunter, Ruud; Tinga, Tiedo

    Advances in sensor technology have enabled companies to make significant progress towards achieving condition-based maintenance (CBM). CBM provides the opportunity to perform maintenance actions more effectively. However, scheduling maintenance at the unit level may imply a high maintenance

  13. Reducing costs by clustering maintenance activities for multiple critical units

    NARCIS (Netherlands)

    de Jonge, Bram; Klingenberg, Warse; Teunter, Ruud; Tinga, Tiedo

    2015-01-01

    Advances in sensor technology have enabled companies to make significant progress towards achieving condition-based maintenance (CBM). CBM provides the opportunity to perform maintenance actions more effectively. However, scheduling maintenance at the unit level may imply a high maintenance

  14. Insight into the maintenance of odontogenic potential in mouse dental mesenchymal cells based on transcriptomic analysis

    Directory of Open Access Journals (Sweden)

    Yunfei Zheng

    2016-02-01

    Full Text Available Background. Mouse dental mesenchymal cells (mDMCs from tooth germs of cap or later stages are frequently used in the context of developmental biology or whole-tooth regeneration due to their odontogenic potential. In vitro-expanded mDMCs serve as an alternative cell source considering the difficulty in obtaining primary mDMCs; however, cultured mDMCs fail to support tooth development as a result of functional failures of specific genes or pathways. The goal of this study was to identify the genes that maintain the odontogenic potential of mDMCs in culture. Methods. We examined the odontogenic potential of freshly isolated versus cultured mDMCs from the lower first molars of embryonic day 14.5 mice. The transcriptome of mDMCs was detected using RNA sequencing and the data were validated by qRT-PCR. Differential expression analysis and pathway analysis were conducted to identify the genes that contribute to the loss of odontogenic potential. Results. Cultured mDMCs failed to develop into well-structured tooth when they were recombined with dental epithelium. Compared with freshly isolated mDMCs, we found that 1,004 genes were upregulated and 948 were downregulated in cultured mDMCs. The differentially expressed genes were clustered in the biological processes and signaling pathways associated with tooth development. Following in vitro culture, genes encoding a wide array of components of MAPK, TGF-β/BMP, and Wnt pathways were significantly downregulated. Moreover, the activities of Bdnf, Vegfα, Bmp2, and Bmp7 were significantly inhibited in cultured mDMCs. Supplementation of VEGFα, BMP2, and BMP7 restored the expression of a subset of downregulated genes and induced mDMCs to form dentin-like structures in vivo. Conclusions. Vegfα, Bmp2, and Bmp7 play a role in the maintenance of odontogenic potential in mDMCs.

  15. Factors Influencing Army Maintenance

    Science.gov (United States)

    1989-01-01

    Harz (1981), reports the results of questioning largc- numbers of Subject Matter Experts (SMEs) involved in the maintenance process. The second type of...identified maintenance problems (e.g., Kokenes, 1987; Harz , 1981). The second step was the identificatl i of demand factors that affect the actual...Kokenes, 1987; Harz , 1981). Second, if any of the data on which allocations are based are faulty, or budgetary decisions require a cutback in

  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. Interval of Routine Maintenance and Maintenance Performance: A Literature Review

    Directory of Open Access Journals (Sweden)

    Au-Yong Cheong Peng

    2016-01-01

    Full Text Available In high-rise residential buildings, the quality of facilities management services is significant to the normal operation of the facilities. Unfortunately, lack of concern towards building maintenance, especially preventive maintenance, happens in domestic housing industry in Malaysia. Majority of the maintenance operations of condominiums suffer from lack of planning, lack of proactive maintenance plan, and lack of proper implementation. Thus, this paper reviews the implementation of preventive maintenance strategy, routine maintenance in specific. An extensive review of literature published in 1987 to 2014 is performed for the purpose of this research. The publications are sourced from journal articles, conference proceedings and books. The literature analysis confirms that the routine maintenance of facilities and building services is vital and it can be influential towards the maintenance performance. Subsequently, a theoretical framework is developed, which shows the relationship between routine maintenance of building facilities & services and maintenance performance. The building facilities & services are divided into two categories. They are essential facilities & services that ensure the safety, health, habitability, and operability of buildings; while value-added facilities & services deal with property value, return on investment, and quality living of buildings. Based on the findings, a future research is proposed, which aims to identify the appropriate routine of maintenance for the facilities and services in high-rise residential buildings to improve the maintenance performance.

  18. Effects of citrate-enriched bicarbonate based dialysate on anticoagulation and dialyzer reuse in maintenance hemodialysis patients.

    Science.gov (United States)

    Rocha, Amanda D; Padua, Vanessa C; Oliveira, Esther; Guimaraes, Márcia M; Lugon, Jocemir R; Strogoff de Matos, Jorge P

    2014-04-01

    Systemic anticoagulation with unfractionated heparin is commonly used in maintenance hemodialysis (HD), but it increases the risk of bleeding complications. We investigated whether the use of citrate-enriched bicarbonate based dialysate (CD) would reduce systemic anticoagulation without compromising the efficacy of reprocessed dialyzers. This is a crossover study in which half of a total of 30 patients initially underwent HD with acetate-enriched bicarbonate based dialysate and a standard heparin dose of ∼ 100 IU/kg (Treatment A), whereas the remaining patients were treated with CD and a 30% reduced heparin dose (Treatment B). After 12 consecutive HD sessions in each treatment, the dialysate and heparin doses were reversed, then followed for another period of 12 HD sessions. The two treatment phases were split by a washout period of six HD sessions using acetate-enriched bicarbonate based dialysate and standard heparin dose. Systemic anticoagulation was higher in Treatment A. The activated partial thromboplastin time at the end of HD session was 68 ± 36 seconds in Treatment A and 47 ± 16 seconds in Treatment B (P = 0.005). Sixty-eight percent of the dialyzers remained adequate until the 12th use in Treatment A and 61% did so in Treatment B (P = 0.63). Patients had three and 24 cramps episodes during Treatment A and B, respectively (P < 0.001). Nine and 26 symptomatic intradialytic hypotension episodes were seen in Treatment A and B, respectively, (P = 0.003). In conclusion, the use of CD had a favorable effect on anticoagulation in the extracorporeal circuit in patients on maintenance HD, but it was also associated with more hypotension and cramps. © 2013 International Society for Hemodialysis.

  19. Managed maintenance, the next step in power plant maintenance

    International Nuclear Information System (INIS)

    Butterworth, G.; Anderson, T.M.

    1984-01-01

    The Westinghouse Nuclear Services Integration Division managed maintenance services are described. Essential to the management and control of a total plant maintenance programme is the development of a comprehensive maintenance specification. During recent years Westinghouse has jointly developed total plant engineering-based maintenance specifications with a number of utilities. The process employed and the experience to date are described. To efficiently implement the maintenance programme Westinghouse has developed a computer software program specifically designed for day to day use at the power plant by maintenance personnel. This program retains an equipment maintenance history, schedules maintenance activities, issues work orders and performs a number of sophisticated analyses of the maintenance backlog and forecast, equipment failure rates, etc. The functions of this software program are described and details of Westinghouse efforts to support the utilities in reducing outage times through development of predefined outage plans for critical report maintenance activities are given. Also described is the experience gained in the training of specialized maintenance personnel, employing competency-based training techniques and equipment mock-ups, and the benefits experienced, in terms of improved quality and productivity of maintenance performed. The success experienced with these methods has caused Westinghouse to expand the use of these training techniques to the more routine skill areas of power plant maintenance. A significant reduction in the operating costs of nuclear power plants will only be brought about by a significant improvement in the quality of maintenance. Westinghouse intends to effect this change by expanding its international service capabilities and to make major investments in order to promote technological developments in the area of power plant maintenance. (author)

  20. Availability analysis of mechanical systems with condition-based maintenance using semi-Markov and evaluation of optimal condition monitoring interval

    Science.gov (United States)

    Kumar, Girish; Jain, Vipul; Gandhi, O. P.

    2018-03-01

    Maintenance helps to extend equipment life by improving its condition and avoiding catastrophic failures. Appropriate model or mechanism is, thus, needed to quantify system availability vis-a-vis a given maintenance strategy, which will assist in decision-making for optimal utilization of maintenance resources. This paper deals with semi-Markov process (SMP) modeling for steady state availability analysis of mechanical systems that follow condition-based maintenance (CBM) and evaluation of optimal condition monitoring interval. The developed SMP model is solved using two-stage analytical approach for steady-state availability analysis of the system. Also, CBM interval is decided for maximizing system availability using Genetic Algorithm approach. The main contribution of the paper is in the form of a predictive tool for system availability that will help in deciding the optimum CBM policy. The proposed methodology is demonstrated for a centrifugal pump.

  1. 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.

  2. Defense Budget: DOD Needs to Improve Reporting of Operation and Maintenance Base Obligations

    Science.gov (United States)

    2016-08-01

    obligations by base and OCO appropriations for OCO reporting purposes , but DOD’s financial management regulations do not require it to...Accounting Standards and Other Pronouncements, as Amended, Statement of Federal Financial Accounting Standards 4: Managerial Cost Accounting Standards and... statements accompanying annual appropriations acts. DOD financial management officials execute both O&M base and O&M OCO funds from the base O&M

  3. Habit-based interventions for weight loss maintenance in adults with overweight and obesity: a randomized controlled trial.

    Science.gov (United States)

    Cleo, Gina; Glasziou, Paul; Beller, Elaine; Isenring, Elisabeth; Thomas, Rae

    2018-04-23

    The objective of this study was to determine whether habit-based interventions are clinically beneficial in achieving long-term (12-month) weight loss maintenance and explore whether making new habits or breaking old habits is more effective. Volunteer community members aged 18-75 years who had overweight or obesity (BMI ≥ 25 kg/m 2 ) were randomized in a single-blind, three-arm, randomized controlled trial. Ten Top Tips (TTT), Do Something Different (DSD), and the attention-only waitlist (WL) control groups were conducted for 12 weeks from July to October 2015. Participants were followed up post-intervention (all groups) and at 6 and 12-month post-intervention (Ten Top Tips and Do Something Different only). The primary outcome was weight-loss maintenance at 12-month follow-up. Secondary outcomes included weight loss at all time points, fruit and vegetable consumption, exercise, wellbeing, depression, anxiety, habit strength, and openness to change. Of the 130 participants assessed for eligibility, 75 adults (mean BMI 34.5 kg/m 2 [SD 6.2]), with a mean age of 51 years were recruited. Assessments were completed post-intervention by 66/75 (88%) of participants and by 43/50 (86%) at 12 months. At post-intervention, participants in the Ten Top Tips (-3.3 kg; 95% CI -5.2, -1.4) and Do Something Different (-2.9 kg; 95% CI -4.3, -1.4) interventions lost significantly more weight (P = < .001) than those on the waitlist control (-0.4 kg; 95% CI -1.2, 0.3). Both intervention groups continued to lose further weight to the 12-month follow-up; TTT lost an additional -2.4 kg (95% CI -5.1, 0.4) and DSD lost -1.7 kg (95% CI -3.4, -0.1). At 12-month post-intervention, 28/43 (65%) of participants in both intervention groups had reduced their total body weight by ≥5%, a clinically important change. Habit-based weight-loss interventions-forming new habits (TTT) and breaking old habits (DSD), resulted in clinically important weight-loss maintenance at 12

  4. 75 FR 4635 - Risk-Based Capital Guidelines; Capital Adequacy Guidelines; Capital Maintenance: Regulatory...

    Science.gov (United States)

    2010-01-28

    ... would have on regulatory capital, the appropriateness of adjusting the risk-based capital treatment of... agencies' risk-based capital and leverage rules would increase regulatory capital requirements for banking... measure risk and allay the agencies' concerns regarding regulatory capital arbitrage (that is, the...

  5. Risk-Based Inspection and Maintenance Planning Optimization of Offshore Wind Turbines

    DEFF Research Database (Denmark)

    Ramírez, José G. Rangel; Sørensen, John Dalsgaard

    2009-01-01

    A risk-based inspection planning (RBI) approach applied to offshore wind turbines (OWT) is presented, based on RBI methodology developed in the last decades in the oil and gas industry. In wind farm (IWF) and single-alone locations are considered using a code-established turbulence models including...

  6. Risk-Based Inspection and Maintenance Planning Optimization of Offshore Wind Turbines

    DEFF Research Database (Denmark)

    Ramírez, José G. Rangel; Sørensen, John Dalsgaard

    2009-01-01

    A risk-based inspection planning (RBI) approach applied to offshore wind turbines (OWT) is presented, based on RBI methodology developed in the last decades in the oil and gas industry. In wind farm (IWF) and single-alone locations are considered using a code-established turbulence models includi...

  7. Use of Just in Time Maintenance of Reinforced Concrete Bridge Structures based on Real Historical Data Deterioration Models

    Directory of Open Access Journals (Sweden)

    Abu-Tair A.

    2016-01-01

    Full Text Available Concrete is the backbone of any developed economy. Concrete can suffer from a large number of deleterious effects including physical, chemical and biological causes. Large owning bridge structures organizations are facing very serious questions when asking for maintenance budgets. The questions range from needing to justify the need for the work, its urgency, to also have to predict or show the consequences of delayed rehabilitation of a particular structure. There is therefore a need for a probabilistic model that can estimate the range of service lives of bridge populations and also the likelihood of level of deteriorations it can reached for every incremental time interval. A model was developed for such estimation based on statistical data from actual inspection records of a large reinforced concrete bridge portfolio. The method used both deterministic and stochastic methods to predict the service life of a bridge, using these service lives in combination with the just in time (JIT principle of management would enable maintenance managers to justify the need for action and the budgets needed, to intervene at the optimum time in the life of the structure and that of the deterioration. The paper will report on the model which is based on a large database of deterioration records of concrete bridges covering a period of over 60 years and include data from over 400 bridge structures. The paper will also illustrate how the service life model was developed and how these service lives combined with the JIT can be used to effectively allocate resources and use them to keep a major infrastructure asset moving with little disruption to the transport system and its users.

  8. Ganho de extensibilidade dos músculos isquiotibiais comparando o alongamento estático associado ou não à crioterapia

    OpenAIRE

    Busarello,Fernanda de Oliveira; Souza,Francieli Tibes de; Paula,Grazieli Francine de; Vieira,Lizyana; Nakayama,Gustavo Kiyosen; Bertolini,Gladson Ricardo Flor

    2011-01-01

    INTRODUÇÃO: A crioterapia é indicada para diminuir o desconforto durante as sessões de alongamento e proporcionar melhores resultados no ganho de extensibilidade. OBJETIVO: O objetivo do estudo foi verificar o ganho de extensibilidade dos músculos isquiotibiais, comparando o alongamento estático com o alongamento estático associado à crioterapia. MATERIAIS E MÉTODOS: Participaram 20 indivíduos, com idade entre 18 e 25 anos, divididos igualmente em dois grupos, os quais realizaram alongamento ...

  9. A study on constructing a machine-maintenance training system based on virtual reality technology

    International Nuclear Information System (INIS)

    Ishii, H.; Kashiwa, K.; Tezuka, T.; Yoshikawa, H.

    1997-01-01

    The development of a VR based training system are presented for teaching disassembling procedures of mechanical machines used in nuclear power plant. The methods of Petri net model for describing trainees' plausible actions in the disassembling process and reduce a right sequence of action sequence are developed as well as realization of the related Petri net editor and the demonstration of the developed VR based training system was demonstrated by example practice of disassembly simulation of check valve. Moreover, the needed future works are also discussed

  10. 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...... is presented where CMI may be incorporated. This framework is addressing to fatigue prone details in support structures for OWT. As part of the results, the life-cycle reliabilities and optimal inspection times are calculated. The influence on inspection times resulting from wind farm location of OWT and data...

  11. Defining dosing pattern characteristics of successful tapers following methadone maintenance treatment: results from a population-based retrospective cohort study.

    Science.gov (United States)

    Nosyk, Bohdan; Sun, Huiying; Evans, Elizabeth; Marsh, David C; Anglin, M Douglas; Hser, Yih-Ing; Anis, Aslam H

    2012-09-01

    To identify dose-tapering strategies associated with sustained success following methadone maintenance treatment (MMT). Population-based retrospective cohort study. Linked administrative medication dispensation data from British Columbia, Canada. From 25 545 completed MMT episodes, 14 602 of which initiated a taper, 4183 individuals (accounting for 4917 MMT episodes) from 1996 to 2006 met study inclusion criteria. The primary outcome was sustained successful taper, defined as a daily dose ≤5 mg per day in the final week of the treatment episode and no treatment re-entry, opioid-related hospitalization or mortality within 18 months following episode completion. The overall rate of sustained success was 13% among episodes meeting inclusion criteria (646 of 4917), 4.4% (646 of 14 602) among all episodes initiating a taper and 2.5% (646 of 25 545) among all completed episodes in the data set. The results of our multivariate logistic regression analyses suggested that longer tapers had substantially higher odds of success [12-52 weeks versus 52 weeks versus <12 weeks: OR: 6.68; 95% CI: 5.13-8.70], regardless of how early in the treatment episode the taper was initiated, and a more gradual, stepped tapering schedule, with dose decreases scheduled in only 25-50% of the weeks of the taper, provided the highest odds of sustained success (versus <25%: OR: 1.61; 95% CI: 1.22-2.14). The majority of patients attempting to taper from methadone maintenance treatment will not succeed. Success is enhanced by gradual dose reductions interspersed with periods of stabilization. These results can inform the development of a more refined guideline for future clinical practice. © 2012 The Authors, Addiction © 2012 Society for the Study of Addiction.

  12. Perceptions That Influence the Maintenance of Scientific Integrity in Community-Based Participatory Research

    Science.gov (United States)

    Kraemer Diaz, Anne E.; Spears Johnson, Chaya R.; Arcury, Thomas A.

    2015-01-01

    Scientific integrity is necessary for strong science; yet many variables can influence scientific integrity. In traditional research, some common threats are the pressure to publish, competition for funds, and career advancement. Community-based participatory research (CBPR) provides a different context for scientific integrity with additional and…

  13. Comparison of cardiovascular risk factors in maintenance hemodialysis patients based on phase angle of bioimpedance analysis

    Science.gov (United States)

    Muzasti, R. A.; Lubis, H. R.

    2018-03-01

    Mortality and morbidity rate, especially from cardiovascular disease in hemodialysis patients in Indonesia is still quite high. One of indicator to assess the predictive value of mortality is the phase angle (PhA) of bioimpedance analysis (BIA) scan examination. Determining the comparison of BMI and laboratory data as cardiovascular risk factors in hemodialysis patients based on PhA.A cross-sectional analytical study was done on 155 outpatientsin RasyidaRenal Hospital, Medan in 2016. Patients were two groups, namely PhAgroup and ≥ 4 group. The comparison of BMI and laboratory data based on PhA were by analyzingthe independent T-test. A P-value age 40-59 years (56.1%). Based on PhA, 56.7% patients have PhA ≥4. There are differences in the profile of age (p: 0.01), BMI (p: 0.028) and hemoglobin (p: 0.00) between two groups, but not in the profile of albumin (p: 0.071), total cholesterol (p: 0.65), HDL (p: 0.06), LDL (p: 0.07), triglyceride (p: 0.87), calcium (p: 0.59) and phosphorus (p: 0.17).Based onPhA, the cardiovascular risk factors of hemodialysis patients were determined by age, BMI, and hemoglobin.

  14. A Skill-based Robot Co-worker for Industrial Maintenance Tasks

    DEFF Research Database (Denmark)

    Koch, Paul Jacob; van Amstel, Marike Koch; Dębska, Patrycja

    2017-01-01

    This paper investigates the concept of a sensor based robot co-worker working in flexible industrial environments together with and alongside human operators. In this particular work, a realisation of a robot co-worker scenario is developed in order to demonstrate the implementation of a robot co-worker...

  15. Training and Maintenance of a Picture-Based Communication Response in Older Adults with Dementia

    Science.gov (United States)

    Trahan, Maranda A.; Donaldson, Jeanne M.; McNabney, Matthew K.; Kahng, SungWoo

    2014-01-01

    We examined whether adults with dementia could learn to emit a picture-based communication response and if this skill would maintain over time. Three women with moderate to severe dementia were taught to exchange a picture card for a highly preferred activity. All participants quickly learned to exchange the picture card and maintained this…

  16. Platinum-based doublet chemotherapy plus bevacizumab without bevacizumab maintenance in advanced non-small cell lung cancer (NSCLC)

    DEFF Research Database (Denmark)

    Nørøxe, Dorte Schou; Wallerek, Sandra; Sørensen, Jens Benn

    2013-01-01

    We report on a retrospective, consecutive non-randomized group of patients who received bevacizumab plus chemotherapy without bevazicumab maintenance.......We report on a retrospective, consecutive non-randomized group of patients who received bevacizumab plus chemotherapy without bevazicumab maintenance....

  17. Risk-based Operation and Maintenance Approach for Wave Energy Converters Taking Weather Forecast Uncertainties into Account

    DEFF Research Database (Denmark)

    Ambühl, Simon; Kramer, Morten Mejlhede; Sørensen, John Dalsgaard

    2016-01-01

    Inspection and maintenance costs are significant contributors to the cost of energy for wave energy converters. Maintenance can be performed after failure (corrective) or before a breakdown (preventive) occurs. Furthermore, helicopter and boat can be used to transport equipment and personnel to t...

  18. A Methodical Development of Measures of Effectiveness for a Condition-Based Maintenance Management System

    Science.gov (United States)

    2014-06-01

    selecting a CMMS based on the desire to obtain a “silver bullet to magically fix inefficiency and ineffectiveness” (Autin 1998, 33). The following are...repeatable method to develop MOEs. Leibowitz discusses MOEs from a metaphysical operation analyst’s viewpoint. His approach resonates with Sproles’ call...Systems Integration: Theory, Metrics, and Methods. Boca Raton, FL: CRC Press. Leibowitz, Martin L. 1958. “ Metaphysical Considerations Involved in Choosing

  19. PC based simulation of gamma camera for training of operating and maintenance staff

    International Nuclear Information System (INIS)

    Singh, B.; Kataria, S.K.; Samuel, A.M.

    2000-01-01

    Gamma camera- a sophisticated imaging system is used for functional assessment of biological subsystems/organs in nuclear medicine. The radioactive tracer attached to the native substance is injected into the patient. The distribution of radioactivity in the patient is imaged by the gamma camera. This report describes a PC based package for simulation of gamma cameras and effect of malfunctioning of its subsystems on images of different phantoms

  20. Optimization of preventive maintenance cycle based on experimental feedback in nuclear power plants

    International Nuclear Information System (INIS)

    Shi Jie

    2010-01-01

    The preventive replacement method based on the experimental feedback was introduced. In this method, the initial preventive replacement cycle was acquired by expert votes. The preventive replacement cycle combined with the operation experience of the equipment was gained by means of Bayesian theorem. The Optimized preventive replacement cycle can be acquired by comparing the two probabilities that no fault occurs within the cycle. This method was tested on the switches which were used in Daya Bay Nuclear Power Plant and the results indicated its validity. (authors)

  1. Users of free treatment slots at a community-based methadone maintenance clinic.

    Science.gov (United States)

    Wells, E A; Fleming, C; Calsyń, D A; Jackson, T R; Saxon, A J

    1995-01-01

    At a community-based methadone clinic in Seattle, WA, 360 opiate-addicted individuals were enrolled in a treatment demonstration project. The treatment slots were free to clients and, unlike other funded treatment slots, did not require proof of eligibility based on documentation of indigence. The clients were compared with 70 clients enrolled in a research project begun 2 years earlier in which the sample was drawn from a population using normal funding sources at the same program. Subjects in the later demonstration project were older and had fewer years of education. A higher percentage of the demonstration project subjects were African American. These differences indicate that introduction of free treatment opened opportunities to individuals who have difficulty accessing treatment under normal circumstances. Subjects in the treatment demonstration project were more likely to have obtained needles from legal sources and used bleach to clean needles. These findings probably reflect the impact of needle exchange and outreach programs, established in the year prior to the demonstration project.

  2. 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

  3. Elaboration of an implementation approach of a condition-based maintenance through vibration analysis

    Directory of Open Access Journals (Sweden)

    Semma El Mehdi

    2015-01-01

    Full Text Available Vibration analysis is a powerful and widely used tool in industry for monitoring rotating machinery. Despite the possibilities offered by the measuring equipment of vibration through technological progress, companies which practice Vibration Based Analysis (VBM show performance below expectations in terms of machine availability. Our duty then is to develop an approach for the implementation of the VBM taking into consideration the keys to success and avoiding the causes of failure. We carried out an analysis of 30 years of practice of the VBM within a large Moroccan company in the chemical industry, through a collective approach called DCA (in French applied short diagnosis and a survey among national and international experts in the field of the VBM. The synthesis of these studies has led us to propose a comprehensive and structured approach that comes in 5 phases: inventory, feasibility studies, preparation phase, implementation phase, evaluation and improvement phase.

  4. Demand-based maintenance and operators support based on process models; Behovsstyrt underhaall och operatoersstoed baserat paa process modeller

    Energy Technology Data Exchange (ETDEWEB)

    Dahlquist, Erik; Widarsson, Bjoern; Tomas-Aparicio, Elena

    2012-02-15

    There is a strong demand for systems that can give early warnings on upcoming problems in process performance or sensor measurements. In this project we have developed and implemented such a system on-line. The goal with the system is to give warnings about both faults needing urgent actions, as well giving advice on roughly when service may be needed for specific functions. The use of process simulation models on-line can offer a significant tool for operators and process engineers to analyse the performance of the process and make the most correct and fastest decision when problems arise. In this project physical simulation models are used in combination with decision support tools. By using a physical model it is possible to compare the measured data to the data obtained from the simulation and give these deviations as input to a decision support tool with Bayesian Networks (BN) that will result in information about the probability for wrong measurement in the instruments, process problems and maintenance needs. The application has been implemented in a CFB boiler at Maelarenergi AB. After tuning the model the system has been used online during September - October 2010 and May - October 2011, showing that the system is working on-line with respect to running the simulation model but with batch runs with respect to the BN. Examples have been made for several variables where trends of the deviation between simulation results and measured data have been used as input to a BN, where the probability for different faults has been calculated. Combustion up in the separator/cyclones has been detected several times, problems with fuel feed on both sides of the boiler as well. A moisture sensor not functioning as it should and suspected malfunctioning temperature meters as well. Deeper investigations of the true cause of problems have been used as input to tune the BN

  5. 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...

  6. Perceptions that influence the maintenance of scientific integrity in community-based participatory research.

    Science.gov (United States)

    Kraemer Diaz, Anne E; Spears Johnson, Chaya R; Arcury, Thomas A

    2015-06-01

    Scientific integrity is necessary for strong science; yet many variables can influence scientific integrity. In traditional research, some common threats are the pressure to publish, competition for funds, and career advancement. Community-based participatory research (CBPR) provides a different context for scientific integrity with additional and unique concerns. Understanding the perceptions that promote or discourage scientific integrity in CBPR as identified by professional and community investigators is essential to promoting the value of CBPR. This analysis explores the perceptions that facilitate scientific integrity in CBPR as well as the barriers among a sample of 74 professional and community CBPR investigators from 25 CBPR projects in nine states in the southeastern United States in 2012. There were variations in perceptions associated with team member identity as professional or community investigators. Perceptions identified to promote and discourage scientific integrity in CBPR by professional and community investigators were external pressures, community participation, funding, quality control and supervision, communication, training, and character and trust. Some perceptions such as communication and training promoted scientific integrity whereas other perceptions, such as a lack of funds and lack of trust could discourage scientific integrity. These results demonstrate that one of the most important perceptions in maintaining scientific integrity in CBPR is active community participation, which enables a co-responsibility by scientists and community members to provide oversight for scientific integrity. Credible CBPR science is crucial to empower the vulnerable communities to be heard by those in positions of power and policy making. © 2015 Society for Public Health Education.

  7. Fast Fingerprint Database Maintenance for Indoor Positioning Based on UGV SLAM

    Directory of Open Access Journals (Sweden)

    Jian Tang

    2015-03-01

    Full Text Available Indoor positioning technology has become more and more important in the last two decades. Utilizing Received Signal Strength Indicator (RSSI fingerprints of Signals of OPportunity (SOP is a promising alternative navigation solution. However, as the RSSIs vary during operation due to their physical nature and are easily affected by the environmental change, one challenge of the indoor fingerprinting method is maintaining the RSSI fingerprint database in a timely and effective manner. In this paper, a solution for rapidly updating the fingerprint database is presented, based on a self-developed Unmanned Ground Vehicles (UGV platform NAVIS. Several SOP sensors were installed on NAVIS for collecting indoor fingerprint information, including a digital compass collecting magnetic field intensity, a light sensor collecting light intensity, and a smartphone which collects the access point number and RSSIs of the pre-installed WiFi network. The NAVIS platform generates a map of the indoor environment and collects the SOPs during processing of the mapping, and then the SOP fingerprint database is interpolated and updated in real time. Field tests were carried out to evaluate the effectiveness and efficiency of the proposed method. The results showed that the fingerprint databases can be quickly created and updated with a higher sampling frequency (5Hz and denser reference points compared with traditional methods, and the indoor map can be generated without prior information. Moreover, environmental changes could also be detected quickly for fingerprint indoor positioning.

  8. Fast fingerprint database maintenance for indoor positioning based on UGV SLAM.

    Science.gov (United States)

    Tang, Jian; Chen, Yuwei; Chen, Liang; Liu, Jingbin; Hyyppä, Juha; Kukko, Antero; Kaartinen, Harri; Hyyppä, Hannu; Chen, Ruizhi

    2015-03-04

    Indoor positioning technology has become more and more important in the last two decades. Utilizing Received Signal Strength Indicator (RSSI) fingerprints of Signals of OPportunity (SOP) is a promising alternative navigation solution. However, as the RSSIs vary during operation due to their physical nature and are easily affected by the environmental change, one challenge of the indoor fingerprinting method is maintaining the RSSI fingerprint database in a timely and effective manner. In this paper, a solution for rapidly updating the fingerprint database is presented, based on a self-developed Unmanned Ground Vehicles (UGV) platform NAVIS. Several SOP sensors were installed on NAVIS for collecting indoor fingerprint information, including a digital compass collecting magnetic field intensity, a light sensor collecting light intensity, and a smartphone which collects the access point number and RSSIs of the pre-installed WiFi network. The NAVIS platform generates a map of the indoor environment and collects the SOPs during processing of the mapping, and then the SOP fingerprint database is interpolated and updated in real time. Field tests were carried out to evaluate the effectiveness and efficiency of the proposed method. The results showed that the fingerprint databases can be quickly created and updated with a higher sampling frequency (5Hz) and denser reference points compared with traditional methods, and the indoor map can be generated without prior information. Moreover, environmental changes could also be detected quickly for fingerprint indoor positioning.

  9. Maintenance therapy with toceranib following doxorubicin-based chemotherapy for canine splenic hemangiosarcoma.

    Science.gov (United States)

    Gardner, Heather L; London, Cheryl A; Portela, Roberta A; Nguyen, Sandra; Rosenberg, Mona P; Klein, Mary K; Clifford, Craig; Thamm, Douglas H; Vail, David M; Bergman, Phil; Crawford-Jakubiak, Martin; Henry, Carolyn; Locke, Jennifer; Garrett, Laura D

    2015-06-11

    Spenic hemangiosarcoma (HSA) in dogs treated with surgery alone is associated with short survival times, and the addition of doxorubicin (DOX) chemotherapy only modestly improves outcome. The purpose of this study was to evaluate the impact of toceranib administration on progression free survival in dogs with stage I or II HSA following splenectomy and single agent DOX chemotherapy. We hypothesized that dogs with splenic HSA treated with adjuvant DOX followed by toceranib would have prolonged disease-free interval (DFI) and overall survival time (OS) when compared to historical dogs treated with DOX-based chemotherapy alone. Dogs with stage I or II splenic HSA were administered 5 cycles of single-agent DOX every 2 weeks beginning within 14 days of splenectomy. Dogs were restaged 2 weeks after completing DOX, and those without evidence of metastatic disease began toceranib therapy at 3.25 mg/kg every other day. Forty-three dogs were enrolled in this clinical trial. Seven dogs had evidence of metastatic disease either before or at re-staging, and an additional 3 dogs were found to have metastatic disease within 1 week of toceranib administration. Therefore 31 dogs went on to receive toceranib following completion of doxorubicin treatment. Twenty-five dogs that received toceranib developed metastatic disease. The median disease free interval for all dogs enrolled in this study (n = 43) was 138 days, and the median disease free interval for those dogs that went on to receive toceranib (n = 31) was 161 days. The median survival time for all dogs enrolled in this study was 169 days, and the median survival time for those dogs that went on to receive toceranib was 172 days. The use of toceranib following DOX chemotherapy does not improve either disease free interval or overall survival in dogs with stage I or II HSA.

  10. Buildings Lean Maintenance Implementation Model

    Science.gov (United States)

    Abreu, Antonio; Calado, João; Requeijo, José

    2016-11-01

    Nowadays, companies in global markets have to achieve high levels of performance and competitiveness to stay "alive".Within this assumption, the building maintenance cannot be done in a casual and improvised way due to the costs related. Starting with some discussion about lean management and building maintenance, this paper introduces a model to support the Lean Building Maintenance (LBM) approach. Finally based on a real case study from a Portuguese company, the benefits, challenges and difficulties are presented and discussed.

  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. Maintenance management for nuclear power plant 'Integrated valve maintenance'

    International Nuclear Information System (INIS)

    Gerner, P.; Zanner, G.

    2001-01-01

    The deregulation of Europe's power market does force many utilities, and especially nuclear power plant operators, to introduce extensive cost-cutting measures in order to be able to compete within this new environment. The optimization of plant outages provides considerable potential for raising plant availability but can also lower operating costs by reducing e.g. expenditure on maintenance. Siemens Nuclear Power GmbH, in cooperation with plant operators, is currently implementing new and improved service concepts which can have a major effect on the way in which maintenance will be performed in the future. Innovative service packages for maintenance in nuclear power plants are available which can be used to perform a time- and cost-effective maintenance. The concepts encompass optimization of the overall sequence from planning in advance to the individual measures including reduction of the scope of maintenance activities, identification of cost cutting potential and bundling of maintenance activities. The main features of these maintenance activities are illustrated here using the examples of outage planning and integrated valve maintenance. In nuclear power plants approx. 5000 valves are periodically preventively, condition-based or breakdown-based maintained. Because of this large number of valves to be maintained a high potential of improvements and cost reductions can be achieved by performing an optimized, cost-effective maintenance based on innovative methods and tools. Siemens Nuclear Power GmbH has developed and qualified such tools which allow to reduce service costs while maintaining high standards of safety and availability. By changing from preventive to predictive (condition-based) maintenance - the number of valves to be maintained may be reduced considerably. The predictive maintenance is based on the Siemens Nuclear Power GmbH diagnostic and evaluation method (ADAM). ADAM is used to monitor the operability of valves by analytical verification of

  14. Effects of Computer-Based Practice on the Acquisition and Maintenance of Basic Academic Skills for Children with Moderate to Intensive Educational Needs

    Science.gov (United States)

    Everhart, Julie M.; Alber-Morgan, Sheila R.; Park, Ju Hee

    2011-01-01

    This study investigated the effects of computer-based practice on the acquisition and maintenance of basic academic skills for two children with moderate to intensive disabilities. The special education teacher created individualized computer games that enabled the participants to independently practice academic skills that corresponded with their…

  15. Effects of a Physical Education-Based Programme on Health-Related Physical Fitness and Its Maintenance in High School Students: A Cluster-Randomized Controlled Trial

    Science.gov (United States)

    Mayorga-Vega, Daniel; Montoro-Escaño, Jorge; Merino-Marban, Rafael; Viciana, Jesús

    2016-01-01

    The purpose of this study was to examine the effects of a physical education-based development and maintenance programme on objective and perceived health-related physical fitness in high school students. A sample of 111 students aged 12-14 years old from six classes were cluster-randomly assigned to an experimental group (n = 54) or a control…

  16. The Comparison of Effectiveness of Cognitive-Behavioral Group Therapy Based on Coping Skills and Methadone Maintenance Treatment in Improvement of Emotional Regulation Strategies and Relapse Prevention

    Directory of Open Access Journals (Sweden)

    Tahereh Ghorbany

    2011-05-01

    Full Text Available Purpose: This study compared the effectiveness of group cognitive-behavioral therapy based on coping skills (CBT and methadone maintenance therapy (MMT in improvement of emotional regulation strategies and prevention of relapse. Method: The method of the present study was semi-experimental research design (pre-test-post-test with witness group. For sampling 45 substance abuse people who had referred to addiction treatment centers were selected and assigned to three groups of cognitive behavior therapy, methadone maintenance treatment and witness group randomly. The participants in all three groups completed the emotional intelligence questionnaire before and after the intervention. Data were analyzed by covariance method. Results: The results showed that cognitive-behavior therapy in comparison to methadone maintenance therapy and witness group led to significant improvement of emotional regulation in substance abusers, but there was no significant difference between the methadone maintenance treatment group and control group. Also, the rate of relapse in individuals who assigned to cognitive-behavior therapy group in comparison to methadone maintenance therapy and the witness group was significantly lower, but there was no significant difference between methadone therapy and witness. Conclusion: Cognitive-behavior therapy was an effective treatment that can change the cognitive and behavioral variables related to substance abuse, such as emotional regulation strategies. Thus, results suggested that drug abuse treatment programs must target these mediator variables.

  17. Development of standardized component\\0x2010based equipment specifications and transition plan into a predictive maintenance strategy.

    Science.gov (United States)

    2015-12-01

    This project investigated INDOT equipment records and equipment industry standards to produce standard equipment specifications : and a predictive maintenance schedule for the more than 1100 single and tandem axle trucks in use at INDOT. The research...

  18. Development of standardized component\\0x2010based equipment specifications and transition plan into a predictive maintenance strategy : final report.

    Science.gov (United States)

    2015-12-01

    This project investigated INDOT equipment records and equipment industry standards to produce standard equipment specifications : and a predictive maintenance schedule for the more than 1100 single and tandem axle trucks in use at INDOT. The research...

  19. POSSIBILIDADE DE GANHO DE FUSTE EM ESPÉCIES EUXILÓFORAS NATIVAS DA REGIÃO CENTRAL DO RIO GRANDE DO SUL

    Directory of Open Access Journals (Sweden)

    Alessandro Dal’Col Lúcio

    2003-09-01

    Full Text Available O presente trabalho foi desenvolvido com o intuito de observar e quantificar a possibilidade de ganho de fuste em cinco espécies euxilóforas (Angico (Parapiptadenia rigida, Canjerana (Cabralea canjerana, Cedro (Cedrela fissilis, Grápia (Apuleia leiocarpa, e Louro (Cordia trichotoma em matas nativas, não-manejadas, de São João do Polêsine, RS. Foram levantadas 17 parcelas temporárias de 10 x 100 m nas matas nativas do município. Nas árvores das cinco espécies eleitas para este estudo, que apresentavam diâmetro à altura do peito (dap superior a 5 cm, foram medidas a altura total, a altura comercial atual e a altura comercial potencial dos troncos. O ganho de fuste foi definido como a diferença entre a altura comercial atual e potencial, em relação à altura comercial atual e expresso em porcentagem. O percentual médio de ganho de fuste para todas as espécies em conjunto foi superior a 70%. O Louro mostrou um ganho de fuste significativamente menor que as demais espécies. Mediante a análise de regressão (stepwise, selecionou-se modelos matemáticos que melhor descrevem o ganho de fuste de cada espécie e das espécies em conjunto. Os resultados mostraram que existe um potencial para o aumento do valor das formações florestais nativas da região, ainda não-explorado por ações silviculturais.

  20. Maintenance of neural activities in torpid Rhinolophus ferrumequinum bats revealed by 2D gel-based proteome analysis.

    Science.gov (United States)

    Yin, Qiuyuan; Zhang, Yijian; Dong, Dong; Lei, Ming; Zhang, Shuyi; Liao, Chen-Chung; Pan, Yi-Hsuan

    2017-08-01

    Bats are the only mammals capable of self-powered flying. Many bat species hibernate in winter. A reversible control of cerebral activities is critical for bats to accommodate a repeated torpor-arousal cycle during hibernation. Little is known about the molecular mechanisms that regulate neuronal activities in torpid bats. In this study, Rhinolophus ferrumequinum bat brain proteins were fractionated, and their abundance in active and torpid states was compared. Results of 2D gel-based proteomics showed that 38% of identified proteins with a significant change in abundance are involved in synaptic vesicle recycling and cytoskeletal integrity. Changes in the abundance of proteins related to RNA splicing, proteostasis, redox homeostasis, mitochondrial function, and energy metabolism were also detected. In addition, the levels of GNAO1 (guanine nucleotide-binding protein G αo subunit), an important modulator of neuronal transmembrane signaling, were significantly increased in the insoluble protein fraction of torpid bats; this may be due to GNAO1 palmitoylation making it insoluble. Our data provide molecular evidence for the maintenance of neuronal activities in torpid bats and suggest that a reversible palmitoylation of the G protein plays a role in the regulation of neuronal activities during bat hibernation. Copyright © 2017 Elsevier B.V. All rights reserved.

  1. Supervision and prognosis architecture based on dynamical classification method for the predictive maintenance of dynamical evolving systems

    International Nuclear Information System (INIS)

    Traore, M.; Chammas, A.; Duviella, E.

    2015-01-01

    In this paper, we are concerned by the improvement of the safety, availability and reliability of dynamical systems’ components subjected to slow degradations (slow drifts). We propose an architecture for efficient Predictive Maintenance (PM) according to the real time estimate of the future state of the components. The architecture is built on supervision and prognosis tools. The prognosis method is based on an appropriated supervision technique that consists in drift tracking of the dynamical systems using AUDyC (AUto-adaptive and Dynamical Clustering), that is an auto-adaptive dynamical classifier. Thus, due to the complexity and the dynamical of the considered systems, the Failure Mode Effect and Criticity Analysis (FMECA) is used to identify the key components of the systems. A component is defined as an element of the system that can be impacted by only one failure. A failure of a key component causes a long downtime of the system. From the FMECA, a Fault Tree Analysis (FTA) of the system are built to determine the propagation laws of a failure on the system by using a deductive method. The proposed architecture is implemented for the PM of a thermoregulator. The application on this real system highlights the interests and the performances of the proposed architecture

  2. Employment-based abstinence reinforcement as a maintenance intervention for the treatment of cocaine dependence: post-intervention outcomes

    Science.gov (United States)

    DeFulio, Anthony; Silverman, Kenneth

    2011-01-01

    Aims Due to the chronicity of cocaine dependence, practical and effective maintenance interventions are needed to sustain long-term abstinence. We sought to assess the effects of long-term employment-based reinforcement of cocaine abstinence after discontinuation of the intervention. Design Participants who initiated sustained opiate and cocaine abstinence during a 6-month abstinence reinforcement and training program worked as data entry operators and were randomly assigned to a group that could work independent of drug use (Control, n = 24), or an abstinence-contingent employment (n = 27) group that was required to provide cocaine- and opiate-negative urine samples to work and maintain maximum rate of pay. Setting A nonprofit data entry business. Participants Unemployed welfare recipients who persistently used cocaine while in methadone treatment. Measurements Urine samples and self-reports were collected every six months for 30 months. Findings During the employment year, abstinence-contingent employment participants provided significantly more cocaine-negative samples than controls (82.7% and 54.2%; P = .01, OR = 4.61). During the follow-up year, the groups had similar rates of cocaine-negative samples (44.2% and 50.0%; P = .93), and HIV-risk behaviors. Participants’ social, employment, economic, and legal conditions were similar in the two groups across all phases of the study. Conclusions Employment-based reinforcement effectively maintains long-term cocaine abstinence, but many patients relapse to use when the abstinence contingency is discontinued, even after a year of abstinence-contingent employment. Relapse could be prevented in many patients by leaving employment-based abstinence reinforcement in place indefinitely, which could be facilitated by integrating it into typical workplaces. PMID:21226886

  3. Fuzzy Logic Reliability Centered Maintenance

    Directory of Open Access Journals (Sweden)

    Felecia .

    2014-01-01

    Full Text Available Reliability Centered Maintenence (RCM is a systematic maintenence strategy based on system reliability. Application of RCM process will not always come out with a binary output of “yes” and “no”. Most of the time they are not supported with available detail information to calculate system reliability. The fuzzy logic method attempts to eliminate the uncertainty by providing “truth” in different degrees.Data and responses from maintenance department will be processed using the two methods (reliability centered maintenance and fuzzy logic to design maintenance strategy for the company. The results of the fuzzy logic RCM application are maintenance strategy which fit with current and future condition.

  4. Efficiency and relevancy of nuclear power plant maintenance

    International Nuclear Information System (INIS)

    Persson, Kenneth

    2001-12-01

    SKI has the intention to further develop the inspection activities to understand if maintenance is managed and developed efficiently. The task has been to identify criteria important to maintenance efficiency. The maintenance process has been reviewed to find steps in the process where maintenance efficiency preferably can be determined. The most important criteria for efficient maintenance, based on SKI regulations, are linked to the development of the maintenance program and to the follow up of already implemented maintenance programs. To achieve efficient maintenance there should be criteria and judgements at the development of the maintenance program to decide if structures, systems and components (SSK) fulfil their functions. If the deviations are maintenance related, a special maintenance program should be developed and implemented together with the regular maintenance program. To achieve efficient maintenance, the experience from already implemented maintenance, experience from other plant units and external experience should be methodically used at the development of the maintenance program

  5. Explaining Physical Activity Maintenance After a Theory-Based Intervention Among Patients With Rheumatoid Arthritis: Process Evaluation of a Randomized Controlled Trial.

    Science.gov (United States)

    Knittle, Keegan; De Gucht, Véronique; Hurkmans, Emalie; Vlieland, Thea Vliet; Maes, Stan

    2016-02-01

    Regular physical activity (PA) benefits patients with rheumatoid arthritis (RA), particularly when maintained over time. Research in this area has largely focused on factors associated with initiating PA, while factors contributing to PA maintenance, particularly after lifestyle interventions, have received less attention. This study examined whether higher levels of autonomous motivation, self-efficacy for PA, and greater use of self-regulation skills mediated PA initiation and maintenance 6 months after a theory-based motivational interviewing and self-regulation coaching intervention. Seventy-eight individuals with RA were randomized to receive either a patient-education session (control group), or the patient-education session plus 1 motivational interview and 2 self-regulation coaching sessions (treatment group). Mediation analyses examined the effects of this intervention on PA initiation and maintenance through the intermediate variables autonomous motivation, self-efficacy for PA, and use of self-regulation skills. Analyses were controlled for age, sex, and previous levels of PA. The treatment group reported significantly higher autonomous motivation and greater use of self-regulation skills than controls at posttreatment. Increases in PA from baseline to posttreatment were not mediated by any intermediate variables. However, maintenance of PA from posttreatment to followup (6 months later) was mediated by greater autonomous motivation and use of self-regulation skills. Greater autonomous motivation and use of self-regulation skills predict maintenance of PA following a motivational interviewing and self-regulation coaching intervention. In promoting PA among patients with RA, supporting patient autonomy and teaching self-regulation skills, which focus attention on achieving PA goals, may improve long-term maintenance of PA. © 2016, American College of Rheumatology.

  6. Avaliação da mobilização neural sobre o ganho de amplitude de movimento

    Directory of Open Access Journals (Sweden)

    Danilo de Almeida Vasconcelos

    Full Text Available INTRODUÇÃO: A mobilização neural (MN visa a restaurar o movimento e a elasticidade do SN, e é utilizada como método de diagnóstico e tratamento das disfunções de origem neural. OBJETIVO: Verificar os efeitos imediatos da MN sobre o ganho de amplitude de movimento de extensão do cotovelo (ADMEC em indivíduos com tensão neural adversa do nervo mediano (TNAm. METODOLOGIA: A amostra foi composta por estudantes universitários, de ambos os sexos, na faixa etária de 17 a 30 anos. Cada indivíduo foi avaliado bilateralmente por meio do teste de tensão do nervo mediano (ULTT1. Nos casos de teste positivo, foi aplicada a MN do nervo mediano e realizada a avaliação goniométrica imediatamente pré e pós-MN. Os dados foram analisados de forma descritiva e inferencial por meio do Teste de Normalidade Kolmogorov-Smirnov, teste t de Student e teste de Wilcoxon, sendo considerado um nível de significância de 5%. RESULTADOS: A amostra foi composta por 60 voluntários, com idade média de 21,25 ± 0,29 anos, estatura média de 1,66 ± 0,11 metros e peso médio de 63,27 ± 1,53 kg. Observou-se ganho estatisticamente significante (p < 0, 001 da ADMEC em ambos os membros superiores após a MN, com valores de 31,57 ± 20,27° e 20,53 ± 15,27°, pré e pós, respectivamente, no membro superior direito, e 28,68 ± 22,43° e 16,57 ± 15,11°, pré e pós, no membro superior esquerdo. CONCLUSÃO: Neste estudo, a MN foi capaz de melhorar, com resultados imediatos, a ADMEC de forma significativa.

  7. A physics-based model for maintenance of the pH gradient in the gastric mucus layer.

    Science.gov (United States)

    Lewis, Owen L; Keener, James P; Fogelson, Aaron L

    2017-12-01

    It is generally accepted that the gastric mucus layer provides a protective barrier between the lumen and the mucosa, shielding the mucosa from acid and digestive enzymes and preventing autodigestion of the stomach epithelium. However, the precise mechanisms that contribute to this protective function are still up for debate. In particular, it is not clear what physical processes are responsible for transporting hydrogen protons, secreted within the gastric pits, across the mucus layer to the lumen without acidifying the environment adjacent to the epithelium. One hypothesis is that hydrogen may be bound to the mucin polymers themselves as they are convected away from the mucosal surface and eventually degraded in the stomach lumen. It is also not clear what mechanisms prevent hydrogen from diffusing back toward the mucosal surface, thereby lowering the local pH. In this work we investigate a physics-based model of ion transport within the mucosal layer based on a Nernst-Planck-like equation. Analysis of this model shows that the mechanism of transporting protons bound to the mucus gel is capable of reproducing the trans-mucus pH gradients reported in the literature. Furthermore, when coupled with ion exchange at the epithelial surface, our analysis shows that bicarbonate secretion alone is capable of neutralizing the epithelial pH, even in the face of enormous diffusive gradients of hydrogen. Maintenance of the pH gradient is found to be robust to a wide array of perturbations in both physiological and phenomenological model parameters, suggesting a robust physiological control mechanism. NEW & NOTEWORTHY This work combines modeling techniques based on physical principles, as well as novel numerical simulations to test the plausibility of one hypothesized mechanism for proton transport across the gastric mucus layer. Results show that this mechanism is able to maintain the extreme pH gradient seen in in vivo experiments and suggests a highly robust regulation

  8. Maintenance treatment of Uracil and Tegafur (UFT) in responders following first-line fluorouracil-based chemotherapy in metastatic gastric cancer: a randomized phase II study.

    Science.gov (United States)

    Li, Wenhua; Zhao, Xiaoying; Wang, Huijie; Liu, Xin; Zhao, Xinmin; Huang, Mingzhu; Qiu, Lixin; Zhang, Wen; Chen, Zhiyu; Guo, Weijian; Li, Jin; Zhu, Xiaodong

    2017-06-06

    Maintenance therapy proves to be effective in advanced lung and breast cancer after initial chemotherapy. The purpose of this phase II study was to evaluate the efficacy and safety of Uracil and Tegafur (UFT) maintenance in metastatic gastric cancer patients following the first-line fluorouracil-based chemotherapy. Metastatic gastric cancer patients with stable disease or a better response after the completion of first-line chemotherapy were randomized to oral UFT (360mg/m2 × 2 weeks) every 3 weeks until disease progression/intolerable toxicity or to observation (OBS). The primary endpoint was progression-free survival (PFS); the secondary endpoints were overall survival (OS) and safety. The trial was closed after the interim analysis of the 58 enrolled (120 planned) patients. Median PFS was not improved in the UFT group compared with the OBS group (3.2 months versus 3.6 months, P = 0.752), as well as the median OS (14.2 months for both, P = 0.983). However, subgroup analysis showed that low baseline hemoglobin (maintenance therapy (P = 0.032), while the normal hemoglobin patients benefit from the UFT treatment (P = 0.008). Grade 3 to 4 toxicities in the UFT group were anemia (3.4%), thrombocytopenia (3.4%) and diarrhea (6.9%). This trial did not show superiority of UFT maintenance in non-selected patients responding to fluorouracil-based first-line chemotherapy. The normal hemoglobin level at baseline is a predictive biomarker for favorable patient subsets from the maintenance treatment.

  9. Balance maintenance in high-speed motion of humanoid robot arm-based on the 6D constraints of momentum change rate.

    Science.gov (United States)

    Zhang, Da-song; Xiong, Rong; Wu, Jun; Chu, Jian

    2014-01-01

    Based on the 6D constraints of momentum change rate (CMCR), this paper puts forward a real-time and full balance maintenance method for the humanoid robot during high-speed movement of its 7-DOF arm. First, the total momentum formula for the robot's two arms is given and the momentum change rate is defined by the time derivative of the total momentum. The author also illustrates the idea of full balance maintenance and analyzes the physical meaning of 6D CMCR and its fundamental relation to full balance maintenance. Moreover, discretization and optimization solution of CMCR has been provided with the motion constraint of the auxiliary arm's joint, and the solving algorithm is optimized. The simulation results have shown the validity and generality of the proposed method on the full balance maintenance in the 6 DOFs of the robot body under 6D CMCR. This method ensures 6D dynamics balance performance and increases abundant ZMP stability margin. The resulting motion of the auxiliary arm has large abundance in joint space, and the angular velocity and the angular acceleration of these joints lie within the predefined limits. The proposed algorithm also has good real-time performance.

  10. Balance Maintenance in High-Speed Motion of Humanoid Robot Arm-Based on the 6D Constraints of Momentum Change Rate

    Directory of Open Access Journals (Sweden)

    Da-song Zhang

    2014-01-01

    Full Text Available Based on the 6D constraints of momentum change rate (CMCR, this paper puts forward a real-time and full balance maintenance method for the humanoid robot during high-speed movement of its 7-DOF arm. First, the total momentum formula for the robot’s two arms is given and the momentum change rate is defined by the time derivative of the total momentum. The author also illustrates the idea of full balance maintenance and analyzes the physical meaning of 6D CMCR and its fundamental relation to full balance maintenance. Moreover, discretization and optimization solution of CMCR has been provided with the motion constraint of the auxiliary arm’s joint, and the solving algorithm is optimized. The simulation results have shown the validity and generality of the proposed method on the full balance maintenance in the 6 DOFs of the robot body under 6D CMCR. This method ensures 6D dynamics balance performance and increases abundant ZMP stability margin. The resulting motion of the auxiliary arm has large abundance in joint space, and the angular velocity and the angular acceleration of these joints lie within the predefined limits. The proposed algorithm also has good real-time performance.

  11. Environmental Assessment (EA): Proposed Standard Air Munitions Packages Maintenance and Inspection Facility, Hill Air Force Base, Utah

    Science.gov (United States)

    2009-07-09

    Floristic Quality Index HAP Hazardous Air Pollutant M&I Maintenance and Inspection MBTA Migratory Bird Treaty Act MILCON Military Construction...or WCI), and the encroachment of invasive species ( floristic quality index, or FQI). Site surveys quantify the health of a range by producing

  12. Efeitos do ganho de peso gestacional e do aleitamento materno na retenção de peso pós-parto em mulheres da coorte BRISA

    Directory of Open Access Journals (Sweden)

    Deysianne Costa das Chagas

    Full Text Available Este estudo analisou os efeitos do ganho de peso gestacional e do aleitamento materno na retenção de peso pós-parto. Foram acompanhadas 2.607 mulheres da coorte de nascimento BRISA. As variáveis utilizadas foram idade, situação socioeconômica, paridade, índice de massa corporal pré-gestacional, ganho de peso gestacional, duração do aleitamento materno, tempo de acompanhamento após o parto e retenção de peso pós-parto. Foi utilizada modelagem de equações estruturais que permitiu avaliar os efeitos totais, diretos e indiretos das variáveis explicativas na retenção de peso pós-parto. Aumento de um desvio padrão do ganho de peso gestacional correspondeu a um aumento significativo de 0,49 desvio padrão da retenção de peso pós-parto (p < 0,001. Aumento de um desvio padrão da duração do aleitamento materno correspondeu à diminuição média de 0,10 desvio padrão da retenção de peso pós-parto (p < 0,001. Independente do índice de massa corporal pré-gestacional, o ganho de peso gestacional é fator de risco, e a duração do aleitamento materno é fator protetor para a retenção de peso pós-parto.

  13. Ganho de peso gestacional e peso ao nascer do concepto: estudo transversal na região de Jundiaí, São Paulo, Brasil

    Directory of Open Access Journals (Sweden)

    Márcia Regina Campos Costa da Fonseca

    2014-05-01

    Full Text Available O objetivo deste estudo foi determinar a prevalência de sobrepeso e obesidade pré-gravídica e gestacional e verificar a associação com o peso ao nascer do concepto. Estudo descritivo, transversal, quantitativo, realizado com 712 gestantes internadas para o parto no hospital da Faculdade de Medicina de Jundiaí. Variáveis estudadas: perfil sociodemográfico, gestacional, peso pré-gravídico, assistência pré-natal, ganho de peso gestacional total e peso ao nascer do concepto. A maioria (99,7% realizou pré-natal, 84,6% > seis consultas. Prevalência de excesso de peso pré-gravídico (34,7% e de ganho de peso total excessivo (36,9%. Associação significativa foi observada entre classificação do IMC inicial da gestante e classificação do peso do recém-nascido (RN e entre classificação do ganho de peso total da gestante e classificação do peso do RN. Nas gestantes com peso excessivo observou-se maior prevalência de RN com peso adequado, em contrapartida, gestantes com ganho de peso insuficiente tiveram 2,15 vezes mais risco de RN com peso insuficiente e 2,85 vezes mais risco de RN com baixo peso. Conclui-se que embora observado importante percentual de gestantes com excesso de peso, este, não influenciou no peso ao nascer do concepto e sim, o peso insuficiente da gestante.

  14. Maintenance-Ready Web Application Development

    Directory of Open Access Journals (Sweden)

    Ion IVAN

    2016-01-01

    Full Text Available The current paper tackles the subject of developing maintenance-ready web applications. Maintenance is presented as a core stage in a web application’s lifecycle. The concept of maintenance-ready is defined in the context of web application development. Web application maintenance tasks types are enunciated and suitable task types are identified for further analysis. The research hypothesis is formulated based on a direct link between tackling maintenance in the development stage and reducing overall maintenance costs. A live maintenance-ready web application is presented and maintenance related aspects are highlighted. The web application’s features, that render it maintenance-ready, are emphasize. The cost of designing and building the web-application to be maintenance-ready are disclosed. The savings in maintenance development effort facilitated by maintenance ready features are also disclosed. Maintenance data is collected from 40 projects implemented by a web development company. Homogeneity and diversity of collected data is evaluated. A data sample is presented and the size and comprehensive nature of the entire dataset is depicted. Research hypothesis are validated and conclusions are formulated on the topic of developing maintenance-ready 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.

  15. Ganho de extensibilidade dos músculos isquiotibiais comparando o alongamento estático associado ou não à crioterapia

    Directory of Open Access Journals (Sweden)

    Fernanda de Oliveira Busarello

    Full Text Available INTRODUÇÃO: A crioterapia é indicada para diminuir o desconforto durante as sessões de alongamento e proporcionar melhores resultados no ganho de extensibilidade. OBJETIVO: O objetivo do estudo foi verificar o ganho de extensibilidade dos músculos isquiotibiais, comparando o alongamento estático com o alongamento estático associado à crioterapia. MATERIAIS E MÉTODOS: Participaram 20 indivíduos, com idade entre 18 e 25 anos, divididos igualmente em dois grupos, os quais realizaram alongamento e alongamento associado à crioterapia. Foram utilizadas bolsas de gelo, na região posterior da coxa, durante 15 minutos. Em seguida, foi realizada a aplicação do alongamento estático de isquiotibiais, em duas séries, de 30 segundos cada. RESULTADOS: Foram encontradas diferenças significativas na extensibilidade dos músculos isquiotibiais em ambos os grupos, porém não houve diferenças significativas na extensibilidade dos músculos isquiotibiais quando comparado o alongamento estático com o alongamento estático associado à crioterapia. CONCLUSÃO: Houve aumento imediato da extensibilidade dos músculos isquiotibiais. Porém, o uso de crioterapia não se mostrou eficaz para o ganho de extensibilidade.

  16. 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…

  17. 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. 

  18. Gym-based exercise and home-based exercise with telephone support have similar outcomes when used as maintenance programs in adults with chronic health conditions: a randomised trial

    Directory of Open Access Journals (Sweden)

    Paul Jansons

    2017-07-01

    Trial registration: ACTRN12610001035011. [Jansons P, Robins L, O’Brien L, Haines T (2017 Gym-based exercise and home-based exercise with telephone support have similar outcomes when used as maintenance programs in adults with chronic health conditions: a randomised trial. Journal of Physiotherapy 63: 154–160

  19. Preventative maintenance cycle of contact switches for nuclear power plants based on lifetime assessment and economic analysis

    International Nuclear Information System (INIS)

    Shi Jie

    2010-01-01

    An approach to determine the preventive maintenance cycle was proposed in consideration of the lifetime, optimal cost and economy. Two parameters Weibull distribution was used to calculate the lifetime of contact switch. The block replacement model and age replacement model were built with the objective of optimal cost, and the preventive replacement cycle was accounted. Eight proposals for preventive replacement cycle were given. Economy model was applied to assess those proposals and the optimal proposal was confirmed. (authors)

  20. Programmatic Environmental Assessment Addressing the Development, Use, and Maintenance of Military Training Areas at Kirtland Air Force Base, New Mexico

    Science.gov (United States)

    2016-09-30

    Evaporation /Infiltration Pond NFA Adjacent to CAR West & the M203 Range ST-273 Building 618 Septic System, Chemical Laser NFA Adjacent to CAR West & the...associated with the development, use, and maintenance of military training areas on Kirtland AFB and provides environmental protection measures to avoid...implementing the Proposed Action presented in the PEA concluded that by implementing environmental protection measures such as adherence to BMPs for ground

  1. Conceptualisation for implementing total productive maintenance throught the ISO 9001:2008 standard-based quality management system

    Directory of Open Access Journals (Sweden)

    Sivaram, N. M.

    2013-08-01

    Full Text Available his paper conceptualises the integration of total productive maintenance (TPM and ISO 9001 certification by contributing a model called TPM 9001:2008. Through this conceptualisation, the eight TPM pillars are amended to the five major clauses of the ISO 9001:2008 standard. To illustrate this conceptualisation, the contents of a sub-clause of the TPM 9001:2008 model are presented, and the rationale behind its designation is appraised.

  2. Fatores relacionados ao ganho de peso interdialítico em pacientes em hemodiálise

    Directory of Open Access Journals (Sweden)

    Fabiana Baggio Nerbass

    2011-09-01

    Full Text Available INTRODUÇÃO: Estudos têm demonstrado que o ganho de peso interdialítico (GPID de pacientes em hemodiálise (HD é influenciado por vários fatores e que o GPID elevado afeta negativamente os níveis pressóricos desta população. OBJETIVO: Avaliar a relação entre fatores clínicos, demográficos e nutricionais com o GPID de pacientes em hemodiálise. MÉTODOS: Estudo transversal, no qual foram incluídos 278 pacientes em hemodiálise (54% de homens; idade = 54,4 ± 14,4 anos de 6 centros de diálise de Santa Catarina. Para análise do percentual de ganho de peso obtido entre uma e outra sessão de HD (%GPID e da pressão arterial (PA, foi calculada a média obtida das sessões de HD no período de quatro semanas. Como indicadores de estado nutricional foram utilizados o índice de massa corporal (IMC e a avaliação subjetiva global (ASG dos sete pontos. RESULTADOS: A média de %GPID foi 4,06 ± 1,55% da PA pré-diálise 140 ± 50 / 99 ± 25 mmHg e PA pós-diálise 110 ± 27 / 78 ± 10 mmHg. O %GPID se correlacionou inversamente com a idade e com o IMC e diretamente com a PA sistólica pré-diálise e com o tempo em tratamento hemodialítico. O %GPID foi maior no grupo de mulheres e no dos pacientes sem diagnóstico de diabetes mellitus. Pacientes com desnutrição tiveram maior %GPID apenas no subgrupo de pacientes mais jovens, quando comparados aos bem nutridos, segundo a ASG. Quando classificados pelo IMC, este achado foi encontrado no grupo total, no subgrupo das mulheres e no dos pacientes mais jovens. Do total, 24% dos pacientes tinham %GPID elevado (> 5% e quando comparados ao grupo com %GPID adequado, estes apresentaram níveis de PA sistólica pré-diálise elevados e significativamente maiores (144 ± 21 versus 138 ± 20 mmHg; p < 0,05, eram mais novos e tinham menor IMC. CONCLUSÃO: Os resultados deste trabalho mostraram que o %GPID dos pacientes estudados foi influenciado pelo gênero, tempo de diálise, idade e estado

  3. Estado nutricional materno, ganho de peso gestacional e peso ao nascer Maternal nutritional status, gestational weight gain and birth weight

    Directory of Open Access Journals (Sweden)

    Adriana Suely de Oliveira Melo

    2007-06-01

    Full Text Available INTRODUÇÃO: Tanto o estado nutricional materno como o ganho de peso gestacional vem sendo estudado em relação ao papel determinante que desempenham sobre o crescimento fetal e o peso ao nascer. O peso inadequado ao nascer é uma das grandes preocupações da saúde pública devido ao aumento da morbimortalidade no primeiro ano de vida e ao maior risco de desenvolver doenças na vida adulta, tais como a síndrome metabólica, nos casos de baixo peso, e diabetes e obesidade, nos casos de macrossomia. O objetivo deste trabalho foi descrever uma coorte de gestantes, classificando-as de acordo com o estado nutricional inicial, o ganho ponderal gestacional, a resistência nas artérias uterinas e o peso dos recém-nascidos. MÉTODOS: foi acompanhada, a cada quatro semanas gestacionais, uma coorte de 115 gestantes atendidas pelo Programa de Saúde da Família do município de Campina Grande, PB. O estado nutricional inicial foi determinado através do índice de massa corporal (kg/m² para a idade gestacional, e as gestantes classificadas de acordo com os critérios de Atalah. Na 20ª semana, foi estudada a resistência das artérias uterinas, através da dopplervelocimetria. RESULTADOS: o estado nutricional inicial mostrou uma alta prevalência de sobrepeso e obesidade (27%, e uma prevalência significante de desnutrição (23%. Um alto percentual de gestantes ganhou peso excessivo tanto no segundo (44% como no terceiro trimestre (45%. A distribuição do peso ao nascer, indicou uma incidência de 10% de baixo peso e de 9% de macrossomia. Observou-se ainda, uma alta prevalência de incisuras nas artérias uterinas.INTRODUCTION: Maternal nutritional status and gestational weight gain have been addressed because of their importance to fetal growth and birth weight. Inadequate birth weight is a major concern to public health given it has been associated with increasing morbidity-mortality during the first year of life and with increased risks of

  4. Road maintenance planning using network flow modelling

    OpenAIRE

    Yang, Chao; Remenyte-Prescott, Rasa; Andrews, John

    2015-01-01

    This paper presents a road maintenance planning model that can be used to balance out maintenance cost and road user cost, since performing road maintenance at night can be convenient for road users but costly for highway agency. Based on the platform of the network traffic flow modelling, the traffic through the worksite and its adjacent road links is evaluated. Thus, maintenance arrangements at a worksite can be optimized considering the overall network performance. In addition, genetic alg...

  5. Prediction of warfarin maintenance dose in Han Chinese patients using a mechanistic model based on genetic and non-genetic factors.

    Science.gov (United States)

    Lu, Yuan; Yang, Jinbo; Zhang, Haiyan; Yang, Jin

    2013-07-01

    Many attempts have been made to predict the warfarin maintenance dose in patients beginning warfarin therapy using a descriptive model based on multiple linear regression. Here we report the first attempt to develop a comprehensive mechanistic model integrating in vitro-in vivo extrapolation (IVIVE) with a pharmacokinetic-pharmacodynamic model to predict the warfarin maintenance dose in Han Chinese patients. The model incorporates demographic factors [sex, age, body weight (BW)] and the genetic polymorphisms of cytochrome P450 (CYP) 2C9 (CYP2C9) and vitamin K epoxide reductase complex subunit 1 (VKORC1). Information on the various factors, mean warfarin daily dose and International Normalized Ratio (INR) was available for a cohort of 197 Han Chinese patients. Based on in vitro enzyme kinetic parameters for S-warfarin metabolism, demographic data for Han Chinese and some scaling factors, the S-warfarin clearance (CL) was predicted for patients in the cohort with different CYP2C9 genotypes using IVIVE. The plasma concentration of S-warfarin after a single oral dose was simulated using a one-compartment pharmacokinetic model with first-order absorption and a lag time and was combined with a mechanistic coagulation model to simulate the INR response. The warfarin maintenance dose was then predicted based on the demographic data and genotypes of CYP2C9 and VKORC1 for each patient and using the observed steady-state INR (INRss) as a target value. Finally, sensitivity analysis was carried out to determine which factor(s) affect the warfarin maintenance dose most strongly. The predictive performance of this mechanistic model is not inferior to that of our previous descriptive model. There were significant differences in the mean warfarin daily dose in patients with different CYP2C9 and VKORC1 genotypes. Using IVIVE, the predicted mean CL of S-warfarin for patients with CYP2C9*1/*3 (0.092 l/h, n = 11) was 57 % less than for those with wild-type *1/*1 (0.215 l/h, n

  6. Web-based interventions for weight loss and weight maintenance among rural midlife and older women: protocol for a randomized controlled trial

    Directory of Open Access Journals (Sweden)

    Boeckner Linda S

    2011-06-01

    Full Text Available Abstract Background Weight loss is challenging and maintenance of weight loss is problematic among midlife and older rural women. Finding effective interventions using innovative delivery methods that can reach underserved and vulnerable populations of overweight and obese rural women is a public health challenge. Methods/Design This Women Weigh-In for Wellness (The WWW study randomized-controlled trial is designed to compare the effectiveness of theory-based behavior-change interventions using (1 website only, (2 website with peer-led support, or (3 website with professional email-counseling to facilitate initial weight loss (baseline to 6 months, guided continuing weight loss and maintenance (7-18 months and self-directed weight maintenance (19-30 months among rural women ages 45-69 with a BMI of 28-45. Recruitment efforts using local media will target 306 rural women who live within driving distance of a community college site where assessments will be conducted at baseline, 3, 6, 12, 18, 24 and 30 months by research nurses blinded to group assignments. Primary outcomes include changes in body weight, % weight loss, and eating and activity behavioral and biomarkers from baseline to each subsequent assessment. Secondary outcomes will be percentage of women achieving at least 5% and 10% weight loss without regain from baseline to 6, 18, and 30 months and achieving healthy eating and activity targets. Data analysis will use generalized estimating equations to analyze average change across groups and group differences in proportion of participants achieving target weight loss levels. Discussion The Women Weigh-In for Wellness study compares innovative web-based alternatives for providing lifestyle behavior-change interventions for promoting weight loss and weight maintenance among rural women. If effective, such interventions would offer potential for reducing overweight and obesity among a vulnerable, hard-to-reach, population of rural women

  7. Improving the TRIGA facility maintenance by predictive maintenance techniques

    International Nuclear Information System (INIS)

    Preda, M.; Sabau, C.; Barbalata, E.

    1997-01-01

    This work deals with the specific operation of equipment in radioactive environment or in conditions allowing radioactive contamination. The requirements of remote operation ensuring the operators' protection are presented. Also, the requirements of international standards issued by IAEA-Vienna are reviewed. The organizational withdraws of the maintenance activities, based on the standards and maintenance and repair directives still in force, are shown. It is emphasized the fact that this type of maintenance was adequate to a given level of technical development, characteristic for pre-computerized industry, but, at present, it is obsolete and uneconomic both in utilization and maintenance. Such a system constitutes already a burden hindering the efforts of maximizing the availability, maintenance, prolongation the service life of equipment and utilities, finally, of increasing the efficiency of complex installations. Moreover, the predictive maintenance techniques are strongly requested by the character of radioactive installations precluding the direct access in given zones (a potential risk of irradiation or radioactive contamination) of installations during operation. The results obtained by applying the predictive maintenance techniques in the operation of the double circuit irradiation loop, used in the TRIGA reactors, are presented

  8. Efficacy of a meal replacement diet plan compared to a food-based diet plan after a period of weight loss and weight maintenance: a randomized controlled trial

    Directory of Open Access Journals (Sweden)

    Hutchisen Tammy

    2010-03-01

    Full Text Available Abstract Background Obesity has reached epidemic proportions in the United States. It is implicated in the development of a variety of chronic disease states and is associated with increased levels of inflammation and oxidative stress. The objective of this study is to examine the effect of Medifast's meal replacement program (MD on body weight, body composition, and biomarkers of inflammation and oxidative stress among obese individuals following a period of weight loss and weight maintenance compared to a an isocaloric, food-based diet (FB. Methods This 40-week randomized, controlled clinical trial included 90 obese adults with a body mass index (BMI between 30 and 50 kg/m2, randomly assigned to one of two weight loss programs for 16 weeks and then followed for a 24-week period of weight maintenance. The dietary interventions consisted of Medifast's meal replacement program for weight loss and weight maintenance, or a self-selected, isocaloric, food-based meal plan. Results Weight loss at 16 weeks was significantly better in the Medifast group (MD versus the food-based group (FB (12.3% vs. 6.9%, and while significantly more weight was regained during weight maintenance on MD versus FB, overall greater weight loss was achieved on MD versus FB. Significantly more of the MD participants lost ≥ 5% of their initial weight at week 16 (93% vs. 55% and week 40 (62% vs. 30%. There was no difference in satiety observed between the two groups during the weight loss phase. Significant improvements in body composition were also observed in MD participants compared to FB at week 16 and week 40. At week 40, both groups experienced improvements in biochemical outcomes and other clinical indicators. Conclusions Our data suggest that the meal replacement diet plan evaluated was an effective strategy for producing robust initial weight loss and for achieving improvements in a number of health-related parameters during weight maintenance, including inflammation

  9. Efficacy of Web-Based Weight Loss Maintenance Programs: A Randomized Controlled Trial Comparing Standard Features Versus the Addition of Enhanced Personalized Feedback over 12 Months.

    Science.gov (United States)

    Collins, Clare E; Morgan, Philip J; Hutchesson, Melinda J; Oldmeadow, Christopher; Barker, Daniel; Callister, Robin

    2017-11-08

    Few randomized controlled trials (RCT) have evaluated the efficacy of web-based programs targeting maintenance of lost weight. The aims of this study were to evaluate two versions of a commercially available web-based weight loss maintenance (WLM) program and examine whether the provision of enhanced feedback was associated with better WLM. The study was an assessor-blinded RCT of change in body mass index (BMI) over 12 months WLM. Participants were 227 adults (44% male, 42.3 ± 10.1 years, BMI 30.4 ± 4.1 kg/m²) randomized to either a basic (Basic WLM) or enhanced program with additional support (Enhanced WLM). Analysis was intention-to-treat with imputation using last observation carried forward. There was no significant weight rebound from the start of weight loss maintenance to 12 months for either group (mean: basic 1.3%, enhanced 1.5%) and limited change in secondary outcomes for either program. There were no significant between-group differences in the primary outcome of change in BMI (basic -0.5 (1.9) kg/m², enhanced -0.5 (1.6) kg/m², p = 0.93). In conclusion, a web-based WLM program was effective in preventing weight regain over one year following weight loss. However, the addition of personalized e-feedback provided limited additional benefits compared to a standard program. Given the potential reach of web-based approaches, further research examining which web-based program components optimize weight outcomes long-term is required.

  10. Efficacy of Web-Based Weight Loss Maintenance Programs: A Randomized Controlled Trial Comparing Standard Features Versus the Addition of Enhanced Personalized Feedback over 12 Months

    Directory of Open Access Journals (Sweden)

    Clare E. Collins

    2017-11-01

    Full Text Available Few randomized controlled trials (RCT have evaluated the efficacy of web-based programs targeting maintenance of lost weight. The aims of this study were to evaluate two versions of a commercially available web-based weight loss maintenance (WLM program and examine whether the provision of enhanced feedback was associated with better WLM. The study was an assessor-blinded RCT of change in body mass index (BMI over 12 months WLM. Participants were 227 adults (44% male, 42.3 ± 10.1 years, BMI 30.4 ± 4.1 kg/m2 randomized to either a basic (Basic WLM or enhanced program with additional support (Enhanced WLM. Analysis was intention-to-treat with imputation using last observation carried forward. There was no significant weight rebound from the start of weight loss maintenance to 12 months for either group (mean: basic 1.3%, enhanced 1.5% and limited change in secondary outcomes for either program. There were no significant between-group differences in the primary outcome of change in BMI (basic −0.5 (1.9 kg/m2, enhanced −0.5 (1.6 kg/m2, p = 0.93. In conclusion, a web-based WLM program was effective in preventing weight regain over one year following weight loss. However, the addition of personalized e-feedback provided limited additional benefits compared to a standard program. Given the potential reach of web-based approaches, further research examining which web-based program components optimize weight outcomes long-term is required.

  11. 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....

  12. Weight Loss Maintenance for 2 Years after a 6-Month Randomised Controlled Trial Comparing Education-Only and Group-Based Support in Japanese Adults

    Directory of Open Access Journals (Sweden)

    Yoshio Nakata

    2014-11-01

    Full Text Available Objective: Our previous study, a 6-month randomised controlled trial, demonstrated that a group-based support promoted weight loss as compared to an education-only intervention. The purpose of this study was to examine weight loss maintenance for 2 years. Methods: Originally, 188 overweight Japanese adults, aged 40-65 years, were randomly assigned to 3 groups: control, education-only or group-based support. After the 6-month intervention, 125 participants in the education-only and the group-based support groups were followed up for 2 years. The primary outcome was the amount of weight lost. The participants were retrospectively grouped into quartiles of percent weight loss for secondary analyses. Results: At the end of follow-up, the amount of weight lost in the education-only and the group-based support groups was the same (3.3 kg. Secondary analyses using data of those who completed the study (n = 100 revealed that the participants in the highest quartile of percent weight loss significantly increased their step counts and moderate-to-vigorous physical activity compared with the lowest quartile. No significant differences were observed in the energy intake among the four groups. Conclusion: The effects of group-based support disappear within 2 years. Increasing physical activity may be a crucial factor for successful maintenance of weight loss.

  13. Towards a maintenance semantic architecture.

    OpenAIRE

    Hedi Karray, Mohamed; Chebel-Morello, Brigitte; Zerhouni, Noureddine

    2009-01-01

    International audience; Technological and software progress with the evolution of processes within company have highlighted the need to evolve systems of maintenance process from autonomous systems to cooperative and sharing information system based on software platform. However, this need gives rise to various maintenance platforms. The first part of this study investigates the different types of existing industrial platforms and characterizes them compared to two criteria namely : informati...

  14. Avaliação do crescimento de tecidos e órgãos de novilhos mestiços Holandês-Gir durante o ganho compensatório. 1. Carcaça

    Directory of Open Access Journals (Sweden)

    Almeida Maria Izabel Vieira de

    2001-01-01

    Full Text Available O objetivo deste trabalho foi analisar os efeitos da restrição alimentar anterior ao confinamento sobre o crescimento e a composição química da carcaça e seus componentes em bovinos. Foram utilizados vinte e quatro novilhos mestiços Holandês-Gir com idade de 19,3 ± 5,1 meses e peso vivo de 202,1 ± 49,1 kg, ao início do experimento. Quinze animais foram confinados após um período de restrição de pasto (grupo ganho compensatório, enquanto nove deles tiveram livre acesso ao pasto (grupo ganho contínuo. Foram abatidos três animais de cada grupo, no início, aos 28 e aos 112 dias do confinamento e, aos 56 e 84 dias de confinamento, foram abatidos três animais do grupo de ganho compensatório. Durante o confinamento, os animais do grupo de ganho compensatório e do grupo de ganho contínuo receberam alimentação ad libitum, composta por silagem de milho e 26% de concentrado, na matéria seca. As taxas de crescimento relativo foram avaliadas por meio de equações alométricas. As taxas de deposição de proteína, gordura e energia na carcaça, em relação ao ganho de peso de corpo vazio, não diferiram entre os tratamentos. A deposição de proteína na carcaça, em relação ao ganho de peso vivo, foi maior nos animais em ganho compensatório que nos de ganho contínuo. O ganho de peso compensatório causou redução na deposição de proteína no tecido adiposo e aumento na deposição de gordura nos ossos da carcaça.

  15. Lean thinking for a maintenance process

    Directory of Open Access Journals (Sweden)

    Sherif Mostafa

    2015-01-01

    Full Text Available The maintenance process shares significant operating costs in an organisation. Lean thinking can be incorporated into maintenance activities through applying its principles and practices/tools. Lean maintenance (LM is a prerequisite for lean manufacturing systems. This research proposes a new structure for LM process based on a systematic literature review of a significant number of related articles that were published on LM. The process structure is designed based on the five lean principles to guide and support organisations to pursue maintenance excellence. This study establishes a scheme for LM tools that are structured into 2 level 4 bundles and 26 lean practices/tools and develops a House of Waste (HoW to demonstrate the association between maintenance wastes and the LM tools. With a successful accomplishment of the proposed scheme, the performance of a maintenance department can create more improvement opportunities over time to reach the maintenance excellence status.

  16. Digestibilidade e ganhos em peso de ovinos alimentados com diferentes fontes de volumosos e recebendo somatotropina recombinante bovina (rBST Digestibility and live weight gain of lambs fed different forages and administration of recombinant bovine somatotropin (rBST

    Directory of Open Access Journals (Sweden)

    Jane Maria Bertocco Ezequiel

    1999-01-01

    Full Text Available O objetivo deste trabalho foi avaliar os efeitos da aplicação de 20 mg de somatotropina recombinante bovina (rBST de liberação lenta, em períodos de 14 e 28 dias, sobre a ingestão de matéria seca, os coeficientes de digestibilidade de matéria seca (MS, fibra em detergente ácido (FDA, proteína bruta (PB e energia bruta (EB, o balanço de nitrogênio e o ganho de peso diário, em rações à base de silagem de milho, cana-de-açúcar ou bagaço hidrolisado e concentrado. Foi usado um total de 24 borregos mestiços, não-castrados, com média de 4 a 5 meses de idade e 22 ± 2 kg de PV. Não houve efeito da rBST na ingestão de matéria seca, nas digestibilidades de PB e FDA, no balanço de nitrogênio e no ganho de peso diário dos borregos. A digestibilidade da energia bruta foi influenciada pela aplicação de rBST, quando os diferentes volumosos ou períodos pós-aplicação hormonal foram considerados, porém, somente foi observado efeito da ação hormonal sobre a digestibilidade de MS nas dietas à base de silagem de milho.The objective of this work was to evaluate the effect of the administration of 20 mg of slow liberation bovine somatotropin (rBST on the dry matter intake and on the digestibility coefficient of dry matter (MS, acid detergent fiber, crude protein, crude energy, nitrogen balance and the daily weight gain in lambs fed diets based on corn silage, sugar cane or hydrolyzed bagasse and concentrate. Twenty-four crossbred lambs, averaging 4-5 months of age and 22 + 2 kg LW, were used. There was no effect of the rBST on the dry matter intake, the digestibilities of crude protein, acid detergent fiber, the nitrogen balance and the daily weight gain of the lambs. The gross energy digestibility was affected by the rBST administration when different forages or periods post hormonal administration were considered, however, the effect of the hormonal action was observed only on the dry matter digestibility of corn silage diets.

  17. 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.

  18. Ganho genético avaliado com índices de seleção e com REML/Blup em milho-pipoca

    Directory of Open Access Journals (Sweden)

    Ismael Lourenço de Jesus Freitas

    2013-11-01

    Full Text Available O objetivo deste trabalho foi comparar quatro índices de seleção e o método REML/Blup na avaliação de ganhos genéticos preditos das características de interesse ao programa de melhoramento do milho-pipoca UENF 14. Foram avaliadas 200 progênies de irmãos-completos, em uma safra, em dois ambientes (regiões Norte e Noroeste do Estado do Rio de Janeiro, com duas repetições, o que totalizou 800 observações. Avaliaram-se as características altura média de plantas, altura média de inserção da primeira espiga, estande final, tombamento, diâmetro de colmo, prolificidade, rendimento e capacidade de expansão dos grãos. Entre os índices de seleção testados, o de Mulamba & Mock proporcionou os melhores resultados para a seleção das progênies de irmãos-completos. O método REML/Blup mostrou-se muito eficiente, tendo selecionado progênies com desempenhos relativos elevados e com ganhos genéticos preditos melhores que os dos índices de seleção testados. As progênies selecionadas com uso do método REML/Blup, para maior rendimento de grãos, não são as mesmas selecionadas para maior capacidade de expansão. O índice de Mulamba & Mock e o método REML/Blup proporcionam os melhores ganhos preditos para a população UENF 14.

  19. Corticosterone shifts reproductive behaviour towards self-maintenance in the barn owl and is linked to melanin-based coloration in females.

    Science.gov (United States)

    Almasi, Bettina; Roulin, Alexandre; Jenni, Lukas

    2013-06-01

    Trade-offs between the benefits of current reproduction and the costs to future reproduction and survival are widely recognized. However, such trade-offs might only be detected when resources become limited to the point where investment in one activity jeopardizes investment in others. The resolution of the trade-off between reproduction and self-maintenance is mediated by hormones such as glucocorticoids which direct behaviour and physiology towards self-maintenance under stressful situations. We investigated this trade-off in male and female barn owls in relation to the degree of heritable melanin-based coloration, a trait that reflects the ability to cope with various sources of stress in nestlings. We increased circulating corticosterone in breeding adults by implanting a corticosterone-releasing-pellet, using birds implanted with a placebo-pellet as controls. In males, elevated corticosterone reduced the activity (i.e. reduced home-range size and distance covered within the home-range) independently of coloration, while we could not detect any effect on hunting efficiency. The effect of experimentally elevated corticosterone on female behaviour was correlated with their melanin-based coloration. Corticosterone (cort-) induced an increase in brooding behaviour in small-spotted females, while this hormone had no detectable effect in large-spotted females. Cort-females with small eumelanic spots showed the normal body-mass loss during the early nestling period, while large spotted cort-females did not lose body mass. This indicates that corticosterone induced a shift towards self-maintenance in males independently on their plumage, whereas in females this shift was observed only in large-spotted females. Copyright © 2013 Elsevier Inc. All rights reserved.

  20. 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

  1. Pacific Northwest Laboratory Maintenance Implementation plan

    Energy Technology Data Exchange (ETDEWEB)

    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.

  2. Pacific Northwest Laboratory Maintenance Implementation plan

    Energy Technology Data Exchange (ETDEWEB)

    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.

  3. Avaliação das heteroses materna e individual sobre o ganho de peso do nascimento ao desmame em bovinos Angus x Nelore Evaluation of maternal and individual heterosis on preweaning gain of Angus x Nellore calves

    Directory of Open Access Journals (Sweden)

    Vanerlei Mozaquatro Roso

    2000-06-01

    Full Text Available Dados de 17.796 bovinos Angus x Nelore pertencentes a 50 rebanhos associados ao "Programa Natura", localizados nos Estados de Goiás, Minas Gerais, Mato Grosso, Mato Grosso do Sul, Paraná, Rio Grande do Sul, São Paulo e Tocantins foram analisados para estimar os efeitos das heteroses materna e individual sobre o ganho de peso do nascimento ao desmame. O modelo estatístico utilizado nas análises continha os efeitos fixos da média geral, grupo contemporâneo, heterozigoses materna e individual (covariáveis, efeitos aleatórios de touro (aditivo, vaca (efeito materno composto, segregação mendeliana e resíduo. Para estimar os efeitos, utilizou-se um procedimento iterativo, que alternava análises genéticas para grupos contemporâneos e efeitos aditivos+maternos sobre o ganho de peso pré-ajustado para heteroses e análises, com o objetivo de estimar os efeitos das covariáveis sobre o ganho de peso pré-ajustado para grupo contemporâneo e efeitos aditivos+maternos. O processo foi finalizado quando as estimativas se tornaram estáveis. Os resultados indicaram relação linear positiva entre as heterozigoses e as heteroses materna e individual. Foram obtidos valores de 15,46% (22,62 kg para heterose materna e 9,10% (13,31 kg para heterose individual. Com base no grau de dificuldade para estimar os efeitos de heterose no presente trabalho, é necessário precaução ao sugerir a simples inclusão das heterozigoses no modelo estatístico e deixar que o ajuste se realize automaticamente.Records from 17,796 Angus x Nellore cattle out of 50 Associated Herds from the "Program Nature", in the states of Goiás, Minas Gerais, Mato Grosso, Mato Grosso do Sul, Paraná, Rio Grande do Sul, São Paulo and Tocantins were analyzed in order to estimate the effects of maternal and individual heterosis on the weight gain from birth to weaning. The used statistical model included the fixed effects of a general mean and contemporary groups, maternal and

  4. EFEITO DE MÉTODOS DE CASTRAÇÃO E DO USO DE VERMÍFUGOS SOBRE O GANHO EM PESO DE BOVINOS MESTIÇOS LEITEIROS

    Directory of Open Access Journals (Sweden)

    Danielle Curado Santana Pires Morales

    2006-10-01

    Full Text Available Avaliaram-se neste estudo o efeito de três métodos de castração e a ação de três vermífugos (abamectina, ivermectina e albendazole sobre o ganho em peso de bovinos jovens mestiços leiteiros. Oitenta e quatro novilhos foram distribuídos em um delineamento inteiramente casualizado (DIC, constituindo quatro grupos (GI – castrados pelo método de incisão lateral da bolsa escrotal; Lateral, GII – castrados pelo método da remoção do ápice da bolsa escrotal; Tampão, GIII – castrados com burdizzo e o GIV, os animais permaneceram inteiros como grupo-testemunha. Em cada grupo foram utilizados três princípios ativos para atuarem na recuperação cirúrgica e como estimuantes de crescimento (vermífugos, constituindo três subgrupos de sete animais cada, recebendo respectivamente abamectina, ivermectina e albendazole. A alimentação consistiu de pasto mais suplemento protéico mineral. As pesagens ocorreram em intervalos de 28 dias, com as quais se obteve o ganho de peso médio diário. Os dados foram analisados pelo método dos quadrados mínimos segundo o procedimento LSMEANS do programa computacional SAS (1996. Não houve diferença entre os três métodos de castração estudados. A abamectina foi mais eficiente que o albendazole, imprimindo maior ganho em peso quando os animais estavam em boas condições físicas e o ambiente era favorável. Os animais inteiros mostraram uma tendência a ganhar mais peso do que os castrados. PALAVRAS-CHAVE: Mestiços leiteiros, castração, vermífugo, ganho em peso, bovinos.

  5. Ganho de peso gestacional e peso ao nascer do concepto: estudo transversal na região de Jundiaí, São Paulo, Brasil

    OpenAIRE

    Márcia Regina Campos Costa da Fonseca; Ruy Laurenti; Caroline Roveri Marin; Maria Cristina Traldi

    2014-01-01

    O objetivo deste estudo foi determinar a prevalência de sobrepeso e obesidade pré-gravídica e gestacional e verificar a associação com o peso ao nascer do concepto. Estudo descritivo, transversal, quantitativo, realizado com 712 gestantes internadas para o parto no hospital da Faculdade de Medicina de Jundiaí. Variáveis estudadas: perfil sociodemográfico, gestacional, peso pré-gravídico, assistência pré-natal, ganho de peso gestacional total e peso ao nascer do concepto. A maioria (99,7%) rea...

  6. Contabilidade de custos vs. contabilidade de ganhos: respostas às exigências da produção enxuta Cost accounting vs. throughput accounting: answer to the lean production's demands

    Directory of Open Access Journals (Sweden)

    José Antonio de Queiroz

    2010-01-01

    Full Text Available A produção enxuta tem provocado mudanças significativas nas empresas, mudanças estas que não vêm sendo acompanhadas pelos sistemas de gestão econômica, desenvolvidos sobre pressupostos equivocados da produção em massa que defendem que as otimizações locais isoladas resultam na otimização global da empresa. Deste modo, pode-se afirmar que a contabilidade de custos não é capaz de prover as informações necessárias à correta tomada de decisão nas empresas enxutas. Por outro lado, constata-se uma coerência entre os princípios da produção enxuta e os pressupostos que sustentam a contabilidade de ganhos da Teoria das Restrições. Sendo assim, o objetivo deste artigo é apresentar argumentos que respaldem estas afirmações, bem como justifiquem a necessidade da utilização da contabilidade de ganhos como base teórica para a proposta de um método de gestão econômica para a produção enxuta.Lean production has provoked significant changes in companies. These changes have not being followed by the economic management systems, which are developed based on mistaken assumptions made by mass production which argues that isolated local optimizations can lead to the global optimization of the company. In this way, it can be affirmed that cost accounting cannot provide the necessary information for decision making in lean companies. On the other hand, consistency is evidenced between the principles of the lean production and the assumptions that support the throughput accounting of the Theory of Constraints. Therefore, the objective of this article is to present arguments that corroborate these assertions and justify the necessity for the use of the throughput accounting as a theoretical basis for the proposal of an economic management method for lean production.

  7. Azithromycin maintenance therapy in patients with cystic fibrosis : A dose advice based on a review of pharmacokinetics, efficacy, and side effects

    NARCIS (Netherlands)

    Wilms, Erik B.; Touw, Daniel J.; Heijerman, Harry G.M.; Van Der Ent, Cornelis K.

    Azithromycin maintenance therapy results in improvement of respiratory function in patients with cystic fibrosis (CF). In azithromycin maintenance therapy, several dosing schemes are applied. In this review, we combine current knowledge about azithromycin pharmacokinetics with the dosing schedules

  8. Preserved intention maintenance and impaired execution of prospective memory responses in schizophrenia: evidence from an event-based prospective memory study

    Directory of Open Access Journals (Sweden)

    Gyula eDemeter

    2016-04-01

    Full Text Available Executive system dysfunction and impaired prospective memory (PM are widely documented in schizophrenia. However, it is not yet clarified which components of PM function are impaired in this disorder. Two plausible target components are the maintenance of delayed intentions and the execution of PM responses. Furthermore, it is debated whether the impaired performance on frequently used executive tasks is associated with deficit in PM functions. The aim of our study was twofold. First, we aimed to investigate the specific processes involved in event-based PM function, mainly focusing on difference between maintenance of intention and execution of PM responses. Second, we aimed to unfold the possible connections between executive functions, clinical symptoms, and PM performance. An event-based PM paradigm was applied with three main conditions: baseline (with no expectation of PM stimuli, and without PM stimuli, expectation condition (participants were told that PM stimuli might occur, though none actually did, and execution condition (participants were told that PM stimuli might occur, and PM stimuli did occur. This procedure allowed us to separately investigate performances associated with intention maintenance and execution of PM responses. We assessed working memory and set-shifting executive functions by memory span tasks and by the Wisconsin Card Sorting Test (WCST, respectively. Twenty patients diagnosed with schizophrenia and 20 healthy control subjects (matched according to age and education took part in the study. It was hypothesized that patients would manifest different levels of performance in the expectation and execution conditions of the PM task. Our results confirmed that the difference between baseline performance and performance in the execution condition (execution cost was significantly larger for participants diagnosed with schizophrenia in comparison with matched healthy control group. However, this difference was not

  9. A practical procedure for the selection of time-to-failure models based on the assessment of trends in maintenance data

    Energy Technology Data Exchange (ETDEWEB)

    Louit, D.M. [Komatsu Chile, Av. Americo Vespucio 0631, Quilicura, Santiago (Chile)], E-mail: rpascual@ing.puc.cl; Pascual, R. [Centro de Mineria, Pontificia Universidad Catolica de Chile, Av. Vicuna Mackenna 4860, Santiago (Chile); Jardine, A.K.S. [Department of Mechanical and Industrial Engineering, University of Toronto, 5 King' s College Road, Toronto, Ont., M5S 3G8 (Canada)

    2009-10-15

    Many times, reliability studies rely on false premises such as independent and identically distributed time between failures assumption (renewal process). This can lead to erroneous model selection for the time to failure of a particular component or system, which can in turn lead to wrong conclusions and decisions. A strong statistical focus, a lack of a systematic approach and sometimes inadequate theoretical background seem to have made it difficult for maintenance analysts to adopt the necessary stage of data testing before the selection of a suitable model. In this paper, a framework for model selection to represent the failure process for a component or system is presented, based on a review of available trend tests. The paper focuses only on single-time-variable models and is primarily directed to analysts responsible for reliability analyses in an industrial maintenance environment. The model selection framework is directed towards the discrimination between the use of statistical distributions to represent the time to failure ('renewal approach'); and the use of stochastic point processes ('repairable systems approach'), when there may be the presence of system ageing or reliability growth. An illustrative example based on failure data from a fleet of backhoes is included.

  10. Improvement of E and P PETROBRAS maintenance program by an RCM tool; MCC Net: software de revisao de planos de manutencao com base M.C.C. Metodo qualitativo

    Energy Technology Data Exchange (ETDEWEB)

    Frydman, Bernardo; Okada, Ricardo Yoshinori [PETROBRAS, Rio de Janeiro, RJ (Brazil). Exploracao e Producao; Souza, Arleniro Oliveira de [PETROBRAS, AM (Brazil). Unidade de Exploracao e Producao da Bacia do Solimoes; Frazao, Nelson A. [PETROBRAS, Macae, RJ (Brazil). Unidade de Negocios da Bacia de Campos

    2004-07-01

    The objective of this paper are remember some basic concepts necessaries to understanding the Reliability Centered Maintenance technique, presenting a report of the RCM applications already developed in the exploration and production segment at PETROBRAS, with some examples of results obtained, presents the premises that based the development of the denominated software MCCNet, developed by PETROBRAS E and P, tool for use of the technique of Reliability Centered Maintenance , for elaboration and/or revision of the preventive maintenance plans of equipment or systems, that it can be used for the study of any process type, and, still presenting the future vision for the subject of RCM in this company segment. (author)

  11. CONSUMO, DIGESTIBILIDADE APARENTE E GANHO DE PESO EM BOVINOS DE CORTE CONFINADOS SUPLEMENTADOS COM CULTURA DE LEVEDURA (Saccharomyces cerevisiae cepa 1026 INTAKE, APPARENT DIGESTIBILITY AND LIVE WEIGHT GAIN OF BEEF CATTLE IN CONFINEMENT SUPPLEMENTED WITH YEAST CULTURE (Saccharomyces cerevisiae 1026

    Directory of Open Access Journals (Sweden)

    Joice Stein

    2008-10-01

    Full Text Available

    Objetivou-se, com o presente trabalho, avaliar os efeitos da inclusão de cultura de levedura no ganho de peso, consumo, digestibilidade aparente da matéria seca (MS, matéria orgânica (MO, proteína bruta (PB, extrato etéreo (EE, fibra em detergente neutro (FDN, fibra em detergente ácido (FDA, hemicelulose (HCEL, carboidratos totais (CHOT e carboidratos não fibrosos (CNF. Foram realizados dois experimentos utilizando novilhos ½ Red Angus ½ Nelore, alimentados com proporção de 1:1 da relação volumoso:concentrado, com base na MS. Utilizou-se o delineamento inteiramente casualizado nos dois experimentos. Os tratamentos foram inclusão ou não de cultura de levedura (1 g/100 kg de peso vivo à dieta dos animais. No primeiro experimento, mantiveram-se, em sistema de confinamento, quatro grupos com quarenta animais cada, dois com suplementação e dois sem suplementação; no segundo experimento, mantiveram-se dez animais canulados no rúmen e distribuídos igualmente nos tratamentos. Não houve diferença (P>0,05 entre os tratamentos em relação ao consumo e à digestibilidade aparente da MS, MO, PB, EE, FDN, FDA, HCEL, CHOT e CNF. Para os valores de ganho de peso também não houve diferença (P>0,05 entre os tratamentos. Esses resultados indicam que, em dietas com proporções de volumoso:concentrado 1:1, a suplementação com cultura de levedura não influencia o ganho de peso, o consumo e a digestibilidade aparente

    PALAVRAS-CHAVES: Aditivos, confinamento, novilhos, probióticos

    This work evaluated the effect of including yeast culture on live weight gain, intake and apparent digestibility of the dry matter (DM, organic matter (OM, crude protein (CP, ether extract (EE, neutral detergent fiber (NDF and acid detergent fiber (ADF, hemicellulose (HCEL, total carbohydrates (TCHO and nonfiber carbohydrates (NFC. Two experiments were realized using ½ Red Angus ½ Nellore steers fed with 1

  12. EFEITOS DA UTILIZAÇÃO DO DISPOSITIVO INTRA-UTERINO (DIU SOBRE O GANHO DE PESO E O RENDIMENTO DE CARCAÇA DE NOVILHAS NELORE DESTINADAS AO ABATE

    Directory of Open Access Journals (Sweden)

    João Maurício Lucas Gordo

    2006-10-01

    Full Text Available Com o objetivo de avaliar os efeitos da implantação de dispositivos intra-uterinos (DIU sobre o ganho de peso corpóreo, rendimento e peso de carcaça, assim como sobre a função ovariana, analisando a ocorrência de androgenização natural e endógena, 41 novilhas da raça Nelore, com idade entre treze e quinze meses, foram distribuídas aleatoriamente em dois grupos experimentais, sendo o grupo controle (GC, n=19 sem uso do dispositivo e o grupo tratado (GT-DIU, n=22, com aplicação do DIU. As novilhas foram mantidas, por 421 dias, em sistema extensivo de manejo em pastagem de Brachiaria brizanhta cv. Marandu e suplementadas com mineral durante o período chuvoso e mistura protéica no período da seca, na região do Brasil Central. A avaliação da ocorrência de comportamento estral foi feita com o auxílio de rufiões. Os animais foram pesados no primeiro dia do experimento, e a cada 28 dias, até o abate. Durante as pesagens, foram colhidas amostras de sangue para dosagem sérica de testosterona. Vinte e quatro horas antes do abate, as fêmeas foram pesadas, e durante os procedimentos pós-abate as meias carcaças foram pesadas, calculando-se o rendimento dos quartos. Não houve diferença estatística significante (p<0,05 entre os resultados obtidos para GC e GT quanto aos parâmetros ganho de peso vivo, peso final, rendimento e peso da carcaça quente. Quanto às concentrações séricas de testosterona, não foi observada diferença estatisticamente significativa (P < 0,05 entre os grupos, até o 402º dia de experimento, verificando-se, porém, redução nos níveis séricos de testosterona ao longo do período experimental. Com base nos resultados obtidos e nas condições de desenvolvimento deste experimento, a utilização do DIU não resultou em vantagens quanto ao ganho de peso vivo, rendimento e peso de carcaça, bem como na supressão de cios de novilhas da raça Nelore. PALAVRAS-CHAVE: Desempenho, dispositivo intra

  13. Fatores associados com a retenção e o ganho de peso pós-parto: uma revisão sistemática Risk factors associated with postpartum weight gain and retention: a systematic review

    Directory of Open Access Journals (Sweden)

    Elisa Maria de Aquino Lacerda

    2004-06-01

    Full Text Available INTRODUÇÃO: A retenção de peso após o parto é um dos determinantes da obesidade em mulheres. Seu desenvolvimento está relacionado com o ganho de peso gestacional, paridade, idade, situação marital, consumo energético, atividade física e lactação, mas as associações encontradas têm se mostrado inconclusivas e contraditórias. Objetivos: Avaliar estudos que identificaram fatores preditores da retenção e ganho de peso após o parto. MATERIAL E MÉTODOS: Foi realizada uma revisão de literatura na Base de Dados LILACS e MEDLINE, referente aos anos de 1993 a 2003. RESULTADOS: Vinte e oito artigos foram identificados, sendo 23 estudos de coorte, quatro estudos transversais e um estudo caso-controle. A maioria dos estudos foi realizada nos EUA e o tempo de acompanhamento após o parto ocorreu principalmente entre seis semanas e 24 meses. Cerca de 25% dos estudos apresentaram perdas superiores a 30%, 61% incluíram adolescentes na amostra e 75% não aferiram o peso pré-gestacional. Sete estudos foram considerados de melhor qualidade, pois utilizaram o peso pré-gestacional medido, incluíram grupo de comparação, excluíram adolescentes, apresentaram perdas de seguimento inferiores a 30% e controlaram para variáveis de confundimento. CONCLUSÃO: Ganho de peso gestacional, raça negra e paridade estão associados positivamente com a retenção de peso pós-parto. As evidências são contraditórias para a variável lactação e insuficientes para as variáveis consumo alimentar e atividade física. São necessários estudos cuidadosamente desenhados para esclarecer estas questões.BACKGROUND: Postpartum weight retention is a trigger for developing obesity in women. It is often associated with weight gain during pregnancy, parity, age, marital status, food intake, physical activity and lactation. However, the associations found have proven to be inconclusive or contradictory. OBJECTIVES: The purpose of this review was to study risk

  14. Prototype tokamak fusion reactor based on SiC/SiC composite material focusing on easy maintenance

    International Nuclear Information System (INIS)

    Nishio, S.; Ueda, S.; Kurihara, R.; Kuroda, T.; Miura, H.; Sako, K.; Takase, H.; Seki, Y.; Adachi, J.; Yamazaki, S.; Hashimoto, T.; Mori, S.; Shinya, K.; Murakami, Y.; Senda, I.; Okano, K.; Asaoka, Y.; Yoshida, T.

    2000-01-01

    If the major part of the electric power demand is to be supplied by tokamak fusion power plants, the tokamak reactor must have an ultimate goal, i.e. must be excellent in construction cost, safety aspect and operational availability (maintainability and reliability), simultaneously. On way to the ultimate goal, the approach focusing on the safety and the availability (including reliability and maintainability) issues must be the more promising strategy. The tokamak reactor concept with the very high aspect ratio configuration and the structural material of SiC/SiC composite is compatible with this approach, which is called the DRastically Easy Maintenance (DREAM) approach. This is because SiC/SiC composite is a low activation material and an insulation material, and the high aspect ratio configuration leads to a good accessibility for the maintenance machines. As the intermediate steps along this strategy between the experimental reactor such as international thermonuclear experimental reactor (ITER) and the ultimate goal, a prototype reactor and an initial phase commercial reactor have been investigated. Especially for the prototype reactor, the material and technological immaturities are considered. The major features of the prototype and commercial type reactors are as follows. The fusion powers of the prototype and the commercial type are 1.5 and 5.5 GW, respectively. The major/minor radii for the prototype and the commercial type are of 12/1.5 m and 16/2 m, respectively. The plasma currents for the prototype and the commercial type are 6 and 9.2 MA, respectively. The coolant is helium gas, and the inlet/outlet temperatures of 500/800 and 600/900 deg. C for the prototype and the commercial type, respectively. The thermal efficiencies of 42 and 50% are obtainable in the prototype and the commercial type, respectively. The maximum toroidal field strengths of 18 and 20 tesla are assumed in the prototype and the commercial type, respectively. The thermal

  15. Evaluating Variations of Bladder Volume Using an Ultrasound Scanner in Rectal Cancer Patients during Chemoradiation: Is Protocol-Based Full Bladder Maintenance Using a Bladder Scanner Useful to Maintain the Bladder Volume?

    Directory of Open Access Journals (Sweden)

    Hong In Yoon

    Full Text Available The maintenance of full bladder is important to reduce radiation-induced toxicities and maintain the therapeutic consistency in locally advanced rectal cancer patients who underwent radiotherapy (RT. So, the aim of this study was to evaluate the effectiveness of protocol-based full bladder maintenance by assessing bladder volume variation using an ultrasound bladder scanner to maintain bladder volume.From March 2011 to May 2011, twenty consecutive rectal cancer patients receiving external beam RT participated in this prospective study. Protocol-based full bladder maintenance consisted of education, training and continuous biofeedback by measuring bladder volume. Bladder volume was measured by bladder scan immediately before simulation CT scan and before each treatment three times weekly during the RT period. The relative bladder volume change was calculated. Intra-patient bladder volume variations were quantified using interquartile range (IQR of relative bladder volume change in each patient. We compared intra-patient bladder volume variations obtained (n=20 with data from our previous study patients (n=20 performing self-controlled maintenance without protocol.Bladder volumes measured by bladder scan highly correlated with those on simulation CT scan (R=0.87, p<0.001. Patients from this study showed lower median IQR of relative bladder volume change compared to patients of self-controlled maintenance from our previous study, although it was not statistically significant (median 32.56% vs. 42.19%, p=0.058. Upon logistic regression, the IQR of relative bladder volume change was significantly related to protocol-based maintenance [relative risk 1.045, 95% confidence intervals (CI 1.004-1.087, p=0.033]. Protocol-based maintenance included significantly more patients with an IQR of relative bladder volume change less than 37% than self-controlled maintenance (p=0.025.Our findings show that bladder volume could be maintained more consistently during

  16. 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...

  17. 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...

  18. Movable bridge maintenance monitoring.

    Science.gov (United States)

    2013-10-01

    Movable bridges have particular maintenance issues, which cost considerably more than those of fixed bridges, : mostly because of the complex interaction of the mechanical, electrical and structural components. In order to track : maintenance and ope...

  19. Conteúdo corporal e exigências líquidas de energia e proteína de novilhos mestiços Holandês-Gir em ganho compensatório

    Directory of Open Access Journals (Sweden)

    Almeida Maria Izabel Vieira de

    2001-01-01

    Full Text Available Foram utilizados 39 novilhos mestiços Holandês-Gir, com o objetivo de avaliar o efeito da restrição alimentar anterior ao confinamento sobre as mudanças na composição corporal e nas exigências líquidas de energia para mantença e ganho de peso e de proteína para ganho de peso. Trinta animais foram submetidos à alta pressão de pastejo, enquanto os nove restantes tiveram oferta ilimitada de pasto (grupo ganho contínuo; após este procedimento, seis animais do primeiro grupo e três do segundo grupo foram abatidos e os restantes foram confinados. Dos 24 animais do grupo ganho compensatório, 12 receberam alimentação ad libitum (grupo ganho compensatório e 12, alimento 15% acima da mantença (grupo mantença, enquanto os seis animais do grupo ganho contínuo receberam a mesma dieta ad libitum. A dieta foi constituída por silagem de milho e 26% de concentrado. A exigência de energia líquida para mantença foi determinada por regressão da produção de calor, em função do consumo de energia metabolizável (EM, extrapolando-se para nível zero de ingestão de EM. Foram ajustadas equações de regressão do logaritmo das quantidades corporais de gordura, proteína e energia, em função do logaritmo do peso corporal vazio (PCVZ. A exigência média de energia líquida para mantença para os animais em ganho compensatório foi de 47,50 kcal/kg0,75/dia. A quantidade de gordura e o conteúdo de energia no peso ganho aumentaram, à medida que o peso vivo dos animais aumentou. Os requerimentos líquidos de energia e proteína para ganho de 1 kg de PCVZ foram de 3,13 Mcal/dia e 189,4 g/dia, respectivamente, para animais com 300 kg de peso vivo.

  20. Commentary: Building the evidence base in support of the American Board of Medical Specialties maintenance of certification program.

    Science.gov (United States)

    Hawkins, Richard E; Weiss, Kevin B

    2011-01-01

    In this issue, Lipner and colleagues describe research supporting the value of the examinations used in the maintenance of certification (MOC) programs of the American Board of Internal Medicine and the American Board of Surgery. The authors of this commentary review the contribution of this research and previous investigations that underscore the value of this component of the American Board of Medical Specialties (ABMS) MOC program. In addition, they point out that the MOC examination is one element of a comprehensive approach to physician lifelong learning, assessment, and quality improvement. The ABMS MOC program requires diplomates of the ABMS member boards to engage in continuous professional development in the six domains of competence and performance previously defined by the ABMS and the Accreditation Council for Graduate Medical Education. Although evidence and a sound rationale exist to support educational and assessment methods that target all six domains, it will be important to continue to build the body of evidence demonstrating the value of MOC to the public and to the profession.

  1. Can reinforcement-based interventions to reduce drug use successfully be adapted to routine opioid maintenance treatment?

    Directory of Open Access Journals (Sweden)

    Michael Specka

    2013-12-01

    Full Text Available INTRODUCTION: Comorbid substance related disorders are a major health problem for patients in opioid maintenance treatment (OMT. It was investigated whether a reinforcement scheme adapted to the regulatory and financial restrictions of routine treatment reduces concomitant drug use. METHODS: OMT patients from 7 clinics who were using cocaine, benzodiazepines, heroin or amphetamines were randomly allocated to either treatment as usual (n = 64 or treatment with an additional escalating reinforcement scheme (n = 72 in which a patient's number of weekly take-home dosages was increased after 1, 4, 8 and 12 consecutive weeks with drug-free urine specimens. Trial duration was 26 weeks. RESULTS: Completion rates were 64% for controls and 62.5% in the experimental group. Mean number of drug-free weeks was 11.3 (SD 8.5 for the control group and 9.8 (8.9 for the experimental group (p = 0.30. CONCLUSION: The intervention was not effective compared to routine treatment. Additional features might be necessary to achieve an effect, e.g. a higher frequency of urine sampling or use of other reinforcers. It has to be further investigated how interventions which have been proven effective in experimental studies can successfully be adapted to routine care conditions.

  2. Predictors of improvement in subjective sleep quality reported by older adults following group-based cognitive behavior therapy for sleep maintenance and early morning awakening insomnia.

    Science.gov (United States)

    Lovato, Nicole; Lack, Leon; Wright, Helen; Kennaway, David J

    2013-09-01

    Cognitive behavior therapy is an effective nonpharmacologic treatment for insomnia. However, individualized administration is costly and often results in substantial variability in treatment response across individual patients, particularly so for older adults. Group-based administration has demonstrated impressive potential for a brief and inexpensive answer to the effective treatment of insomnia in the older population. It is important to identify potential predictors of response to such a treatment format to guide clinicians when selecting the most suitable treatment for their patients. The aim of our study was to identify factors that predict subjective sleep quality of older adults following group-based administration of cognitive behavior therapy for insomnia (CBT-I). Eighty-six adults (41 men; mean age, 64.10 y; standard deviation [SD], 6.80) with sleep maintenance or early morning awakening insomnia were selected from a community-based sample to participate in a 4-week group-based treatment program of CBT-I. Participants were required to complete 7-day sleep diaries and a comprehensive battery of questionnaires related to sleep quality and daytime functioning. Hierarchical multiple regression analyses were used to identify factors predicting subjective sleep quality immediately following treatment and at 3-month follow-up. Sleep diaries reported average nightly sleep efficiency (SE), which was used as the outcome measure of sleep quality. Participants with the greatest SE following treatment while controlling for pretreatment SE were relatively younger and had more confidence in their ability to sleep at pretreatment. These characteristics may be useful to guide clinicians when considering the use of a group-based CBT-I for sleep maintenance or early morning awakening insomnia in older adults. Copyright © 2013 Elsevier B.V. All rights reserved.

  3. 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.)

  4. Avaliação de Perdas e Ganhos nas Decisões Financeiras: Uma Investigação à Luz da Prospect Theory

    Directory of Open Access Journals (Sweden)

    Adriana Fernandes Vasconcelos

    2014-04-01

    Full Text Available As anomalias registradas no mercado financeiro suscitaram o surgimento do ramo das finanças comportamentais, que investiga os aspectos emocionais e cognitivos na tomada de decisão. Nesse contexto, insere-se a Prospect Theory, que se apresenta como alternativa à Teoria da Utilidade Esperada. Esta pesquisa tem como objetivo testar as hipóteses da Prospect Theory a partir do questionário desenvolvido por Thaler e Johnson (1990, que avalia o comportamento dos indivíduos após eventos de perdas e ganhos financeiros. A amostra é composta por 1.152 alunos de graduação da cidade de Caruaru/PE. Os resultados encontrados são semelhantes aos da pesquisa de Thaler e Johnson (1990 e validam parcialmente a Teoria do Prospecto, mas com evidências menos acentuadas. Observou-se que os alunos tendem a não se guiar exclusivamente pelo resultado financeiro, de modo que suas decisões parecem influenciadas pelo componente emocional das perdas e ganhos. Subsidiariamente, verificou-se que as distinções de curso, idade, gênero e renda familiar não alteraram qualitativamente os resultados.

  5. Efeito da vitamina C no ganho de peso e em parâmetros hematológicos de tambaqui Effect of vitamin C on weight and hematology of tambaqui

    Directory of Open Access Journals (Sweden)

    Edsandra Campos Chagas

    2003-03-01

    Full Text Available O objetivo deste trabalho foi avaliar o efeito da suplementação dietária com ácido L-ascórbico (vitamina C no ganho de peso e em parâmetros hematológicos de juvenis de tambaqui, Colossoma macropomum. Após dez semanas, em que foram alimentados com dietas contendo 0, 100 e 500 mg de ácido L-ascórbico por kg de ração, os peixes foram capturados e imediatamente anestesiados para a coleta de sangue da veia caudal e determinação dos parâmetros hematológicos. Animais alimentados com maiores níveis de ascorbato mostraram pesos corpóreos maiores, melhores taxas de conversão alimentar e sobrevivência. A asência de ácido L-ascórbico na ração, além de causar redução nos valores de hematócrito e no número de eritrócitos, que caracteriza anemia, provocou aumento no volume corpuscular médio, na hemoglobina corpuscular média e na concentração de hemoglobina corpuscular média. Esses resultados revelam a importância do ácido L-ascórbico na dieta dos juvenis de tambaqui. O nível de 100 mg de ácido L-ascórbico/kg de ração é adequado, garantindo bom ganho de peso e manutenção da homeostase do organismo.The objective of this work was to estimate the effect of L-ascorbic acid (vitamin C dietary supplementation on the body weight and on the hematology of juveniles tambaqui, Colossoma macropomum. After ten weeks receiving diets containing 0, 100 and 500 mg of L-ascorbic acid per kg of food, the fish were netted from the tanks, immediately anesthetized and blood was withdrawn from caudal vein for analysis of hematological parameters. Animals fed on higher ascorbate levels showed higher final body weight, better feed conversion rate and survival. Also, the L-ascorbic acid free-diet resulted in reduction of hematocrit and red blood cell count, characterizing anemia, and an increase of mean cell volume, mean cellular hemoglobin and mean cellular hemoglobin concentration. These results show the importance of L-ascorbic acid

  6. DADOS DE UMA PROVA DE GANHO DE PESO PARA SELEÇÃO DE REPRODUTORES BOVINOS DE CORTE FEEDING-TEST DATA FOR BEEF CATTLE BULLS SELECTION

    Directory of Open Access Journals (Sweden)

    José Magno Pato

    2007-09-01

    Full Text Available

    O presente trabalho foi realizado em Goiânia - Goiás e teve como objetivos iniciar a seleção de reprodutores através do "feeding-test" e verificar possíveis diferenças de ganhos em peso e pesos finais entre as raças Gir e Nelore. Foram utilizados 48 bezerros controlados e submetidos às mesmas condições de manejo e alimentação: 50% de milho desintegrado (espiga inteira, 25% de fubá de milho, 20% de farelo de algodão e 5% de feno de alfafa. O experimento durou 140 dias e demonstrou que, em termos de ganho e velocidade de ganho em peso, 50% dos animais estavam aptos para a reprodução. Observou-se que existem grandes diferenças de pesos e ganhos em peso tanto dentro quanto entre as raças. Os animais da raça Nelore superam os da raça Gir em peso inicial (198,4 x 178,9 kg, ganho em peso (114,3 x 104,9 kg, mas a significância estatística só foi atingida para os pesos finais. Outras provas deverão ser realizadas, corrigindo-se as falhas aqui apontadas, e trarão certamente melhores informações.

    The present work was carried out in Goiânia - Goiás with the objectives to start in selection of bulls through weights differences between Gir and Nelore breeds. Forty-eight controlled calves were used and submitted to the same conditions of control and feeding: 50% ground snapped corn, 25% corn meal, 20% cottonseed meal and 5% alfafa hay. The experiment lasted 140 days and showed that gain wise and speed gain weights, 60% of the animals was qualified to the reproduction. It was observed that great differences exist in weights and weight gains as in as much as between breeds. The animals of the Nelore’s breed surpass those of the Gir’s breed in initial weight (198.4 versus 178.9 kg, weight gain (114.3 versus 104.9 kg, final weight (312.7 versus 283.8 kg and adusted final weight (312.9 versus 283

  7. Ganho de força e função em idosos por treino isométrico com e sem resposta visual

    Directory of Open Access Journals (Sweden)

    Mauricio Ferraz de Arruda

    2014-07-01

    Full Text Available INTRODUÇÃO: A remediação das alterações fisiológicas que sofrem os idosos é um problema com o qual a saúde pública se defronta com frequência. A premência deste trabalho está em minimizar essa remediação e as alterações que ela propicia no âmbito músculo-esquelético, por meio de um trabalho físico condicionante, que busca aumentar a qualidade de vida dessa população. OBJETIVO: Avaliar o efeito do treinamento físico sob duas ópticas de comando terapêutico, com e sem resposta visual por unidade de pressão, bem como seus possíveis benefícios quanto ao ganho de torque muscular, inerente à funcionalidade citada no questionário de qualidade de vida SF-36, avaliando assim a influência do treinamento físico. MÉTODOS: A avaliação foi realizada por meio de um questionário de qualidade de vida SF-36 e do teste de levantar e sentar, além da aferição da força por meio do esfigmomanômetro modificado (EM. O individuo foi submetido a duas sessões semanais de exercícios durante um mês, com o protocolo de treinamento que constou de três séries de 10 repetições na cadeira flexora e extensora para ambos os joelhos de maneira isométrica. Os dados foram estatisticamente analisados pela análise de variância e desvio padrão (p < 0,05 e correlação de Pearson (p < 0,05. RESULTADOS: Notou-se melhora no quadro geral dos idosos, sendo que houve aumento estatisticamente significante no estado geral de saúde, redução da limitação por aspectos físicos, redução da dor e no aumento da capacidade funcional, bem como um incremento da força de flexão e extensão, que teve reflexo positivo no teste funcional. CONCLUSÃO: Houve correlação extremamente válida entre o ganho de força em flexão com o teste de sentar e levantar, com o qual, apesar de ganho menor comparado ao ganho de força em extensão, estabeleceu-se correlação com o ganho funcional, independentemente da resposta visual ao exercício.

  8. Inhalational Induction and Maintenance of Sevoflurane-Based Anesthesia or Total Intravenous Anesthesia Using Propofol and Fentanyl in Patients with Concomitant Dyscirculatory Encephalopathy

    Directory of Open Access Journals (Sweden)

    V. V. Likhvantsev

    2013-01-01

    Full Text Available Objective: to improve the results of treatment in patients with concomitant cerebrovascular diseases, by reducing the incidence of postoperative delirium due to neuroprotective properties of sevoflurane. Subjects and methods. Eighty2two patients with concomitant dyscirculatory encephalopathy were examined. The goals of the study included evaluating (a efficiency and safety of total intravenous anesthesia (TIVA using propofol versus inhalational induction and (b maintenance of anesthesia (IIMA using sevoflurane in patients with atherosclerotic and hypertensive encephalopathy undergoing noncardiac surgery. Results. The patients from both groups were susceptible to episodes of unintentional cerebral desaturation (rSO2; however, only the TIVA group showed a high correlation between a decrease in rSO2 and increases in the blood levels of S100beta protein, a marker of neuronal damage, and in the incidence of postoperative delirium (r=0.7321; p=0.0000001 diagnosed in accordance to comprehensive clinical examination and MMSE scores. The IIMA group lacked a relationship of MMSE scores to the episodes of cerebral desaturation (r=0.1609; p=0.4860, which is regarded as a manifestation of the neuroprotective effect resulted from anesthetic preconditioning. Conclusion. sevafluran2based inhalational induction and maintenance of anesthesia in patients with atherosclerotic and hypertensive encephalopathy is preferable over intravenous anesthesia with propofol and fentanyl in patients with concomitatnt disregulatory enc encephalopathy. Key words: cerebral desaturation, postoperative delirium, anesthetic preconditioning, europrotection, sevoflurane.

  9. Exploring end user adoption and maintenance of a telephone-based physical activity counseling service for individuals with physical disabilities using the Theoretical Domains Framework.

    Science.gov (United States)

    Tomasone, Jennifer R; Arbour-Nicitopoulos, Kelly P; Pila, Eva; Lamontagne, Marie-Eve; Cummings, Isabelle; Latimer-Cheung, Amy E; Routhier, François

    2017-06-01

    In Canada, two counseling services are offered to facilitate physical activity participation among persons with physical disabilities, yet both have encountered concerns related to the recruitment and retainment of clients. The purpose of this paper is to explore factors related to service adoption among nonusers, and the barriers and facilitators to maintaining service participation among adopters. Individuals who had never enrolled in the services (nonusers, n = 13) as well as current/previous service clients (adopters, n = 26) participated in interviews based on the Theoretical Domains Framework. Transcripts were subjected to deductive thematic analysis according to participant group. Fifteen themes relating to service adoption within 10 of the 12 theoretical domains were identified for nonusers, while 23 themes relating to maintenence of service participation were identified across all 12 theoretical domains for adopters. The findings provide strategies to improve recruitment, adoption, and retention of clients in counseling services and to enhance the experiences of targeted service users. Implications for Rehabiliation Peer support and education for equipment use should be built into physical activity programs to encourage participation among persons with physical disabilities. Programs that encourage physical activity among individuals with disabilities should be designed by practitioners to be responsive to a variety of needs, which are addressed in the program's advertisements and offerings. The Theoretical Domains Framework is a useful framework for providing valuable insight about clients' experiences of adoption and maintenance of a behavior change service, suggesting merit in other rehabilitation settings.

  10. 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

  11. 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)

  12. Uma abordagem de avaliação de processos baseados no mundo dos custos para processos no mundo dos ganhos em instituições de ensino superior Process analisys for higher education institutions: from the cost world to the throughput world

    Directory of Open Access Journals (Sweden)

    Daniel Pacheco Lacerda

    2009-12-01

    Full Text Available O presente artigo detalha o processo específico de elaboração de preços à luz dos princípios da Contabilidade de Custos para uma organização de ensino superior. O trabalho proPõe uma revisão desse processo, tendo como pano de fundo os conceitos da Teoria das Restrições, no que tange a seu Processo de Raciocínio, e as premissas de custos adotadas na chamada Contabilidade dos Ganhos. Assim, o processo de elaboração do preço é avaliado sistemicamente e um redesenho desse processo alinhado à Contabilidade dos Ganhos é proposto.This paper investigates a University's pricing process, comparing two different accounting approaches: traditional cost accounting and Theory of Constraints. Relying on concepts from the Theory of Constraints, this paper applies the principles of the Thinking Process and Throughput Accounting to review the current approach to this process. As a result, the paper evaluates the dynamics behind such processes and, based on throughput accounting, presents a new approach in tackling this.

  13. 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)

  14. 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.

  15. Consolidating Air Force Maintenance Occupational Specialties

    Science.gov (United States)

    2016-01-01

    these questions, the impact of AFS consolidation on active duty KC-135 maintenance personnel at MacDill, McConnell , and Fairchild Air Force Bases...readiness? The analysis presented here considers the impact of AFS consolidation on active-duty KC- 135 maintenance personnel at MacDill, McConnell ... Concept for Air Force Maintenance: Conclusions from Analysis of C-130, F-16, and KC-135 Fleets, Santa Monica, Calif.: RAND Corporation, MG-919-AF, 2010

  16. 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.

  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. Randomised Phase 2 study of maintenance linsitinib (OSI-906) in combination with erlotinib compared with placebo plus erlotinib after platinum-based chemotherapy in patients with advanced non-small cell lung cancer.

    Science.gov (United States)

    Ciuleanu, Tudor-Eliade; Ahmed, Samreen; Kim, Joo-Hang; Mezger, Jörg; Park, Keunchil; Thomas, Michael; Chen, Jihong; Poondru, Srinivasu; VanTornout, Jan M; Whitcomb, Debbie; Blackhall, Fiona

    2017-09-05

    Maintenance therapy is important in advanced/metastatic non-small cell lung cancer (NSCLC). Erlotinib as switch maintenance following platinum-based chemotherapy increases survival. Cross-talk between the epidermal growth factor receptor and insulin-like growth factor receptor (IGFR) pathways mediate resistance to individual receptor blockade. This study compared maintenance linsitinib plus erlotinib vs erlotinib plus placebo in patients with NSCLC. In this Phase II randomised trial, patients without progression following four cycles of first-line platinum-based chemotherapy (N=205) received continuous schedule maintenance oral linsitinib 150 mg or placebo BID combined with erlotinib 150 mg QD for 21-day cycles. The primary endpoint was progression-free survival (PFS). The study was unblinded early due to linsitinib non-superiority. No difference was found between the two treatment groups in median PFS of 125 days linsitinib vs 129 days placebo (P=0.601); no difference in overall survival (OS) was observed. Tolerability was similar, although in the linsitinib group, treatment-related adverse events and discontinuations were more frequent. No drug-drug interaction was implicated. Linsitinib maintenance therapy added to erlotinib did not improve PFS or OS in non-progressing NSCLC patients. This highlights the need for robust biomarkers of response for combinations that incorporate IGFR-targeted therapies in maintenance or other therapeutic settings.

  19. 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

  20. Maintenance therapy in multiple myeloma

    Directory of Open Access Journals (Sweden)

    Jean-Luc Harousseau

    2009-08-01

    Full Text Available The treatment of multiple myeloma (MM has changed dramatically in the past twenty years with the introduction of high-dose therapy plus autologous stem-cell transplantation (ASCT in younger patients and, more recently, of three novel agents (thalidomide, bortezomib, and lenalidomide. When conventional chemotherapy was the only available possibility, complete responses (CR were very rare and the objective of maintenance was to prolong remission duration by continuing the same type of treatment that induced the initial response. With recent therapeutic improvements, CR achievement becomes a realistic goal that, in most cases, is significantly correlated with the outcome (1. Therefore, both the nature and the impact of maintenance therapy have changed. Maintenance therapy is based currently on novel agents, and its objective is not only to control the clone but also to further decrease the tumor burden and improve the quality of response. A number of randomized studies show a benefit from maintenance therapy with novel agents (until now, mostly thalidomide, at least in terms of response rate and progression-free survival (PFS. However, there is still a debate as concerns the impact on overall survival (OS and the optimal administration of maintenance therapy.

  1. “Rejecting the inevitability of poverty”: Empower women for sustainable rural livelihoods through community-based employment intensive rural infrastructure maintenance projects

    CSIR Research Space (South Africa)

    Mashiri, M

    2008-11-01

    Full Text Available ...” (Project supervisor – February 2008)4. Training, knowledge and skills transfer: Participants were technically trained on road maintenance and life skills over the duration of their contract. “…Before the project, we did not know anything about drainage... Family and marriage stability/ instability Appreciative children Communit y Road maintenance & life skills transferred to community Maintenance of community assets Net increase in employment Less time for community meetings and work More...

  2. Sensitivities in Structural Maintenance Planning

    DEFF Research Database (Denmark)

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

    1996-01-01

    A general description of optimal inspection and maintenance planning based on the classical decision theory and the modern reliability theory is given. A number of simplifications to this description is given leading to more appropriate formulations for practical applications. Sensitivities of both...... optimal inspection and maintenance plans as well as the associated costs are given with respect to the assumptions on which the planning has been performed. These sensitivities indicate the significance of the individual assumptions and may be used as a decision tool to reject particular optimal...... inspection and maintenance plans showing too large sensitivity. An example from the offshore industry is given to indicate how the methodologies can be used in practical applications....

  3. Nutritional status and weight gain in pregnant women Estado nutricional y aumento de peso en la mujer embarazada Estado nutricional e ganho de peso de gestantes

    Directory of Open Access Journals (Sweden)

    Ana Paula Sayuri Sato

    2012-06-01

    Full Text Available This study described the nutritional status of 228 pregnant women and the influence of this on birth weight. This is a retrospective study, developed in a health center in the municipality of São Paulo, with data obtained from medical records. Linear regression analysis was carried out. An association was verified between the initial and final nutritional status (pEstado nutricional de 228 embarazadas y su influencia en el peso al nacer fue caracterizado. Estudio desarrollado en centro de salud de São Paulo con datos obtenidos de registros médicos. Análisis de regresión lineal fue realizado. Se verificó asociación entre estado nutricional inicial y final (pCaracterizou-se estado nutricional de 228 gestantes e sua influência no peso ao nascer. Trata-se de estudo retrospectivo desenvolvido num centro de saúde do município de São Paulo, com dados obtidos de prontuários. Realizou-se análise de regressão linear. Verificou-se associação entre estado nutricional inicial e final (p<0,001. A média de ganho total de peso diminuiu das gestantes que iniciaram a gravidez com baixo peso para aquelas que iniciaram com sobrepeso/obesidade (p=0,005, sendo insuficiente para 43,4 e 36,4% das gestantes com peso inicial adequado e para o total das gestantes estudadas, respectivamente. Entretanto, 37,1% daquelas que iniciaram a gravidez com sobrepeso/obesidade finalizaram com ganho excessivo, condição que, no final, afetou quase um quarto das gestantes. Anemia e baixo peso ao nascer foram pouco frequentes, porém, na análise de regressão linear, peso ao nascer associou-se com ganho de peso (p<0,05. Evidencia-se a importância do cuidado nutricional antes e durante a gravidez, para promoção da saúde materno-infantil.

  4. Ganho genético decorrente da substituição anual de cultivares de milho Genetic gain as a result of corn cultivars annual substitution

    Directory of Open Access Journals (Sweden)

    Lindolfo Storck

    2005-09-01

    Full Text Available Cultivares de milho (Zea mays são normalmente substituídas alguns anos após a indicação para cultivo. Os objetivos deste trabalho foram desenvolver e avaliar um teste de hipótese para determinar se as substituições anuais de cultivares, nos ensaios de competição de cultivares indicadas de milho, resultam em ganho genético para produtividade de grãos. Os ensaios de competição de cultivares de milho superprecoce, precoce e normal foram conduzidos nos anos agrícolas de 1998/1999, 1999/2000, 2000/2001 e 2001/2002. O delineamento experimental foi em blocos ao acaso, com três repetições. Cada parcela foi formada por duas fileiras de 5 m de comprimento, com espaçamento de 0,8 m. O ganho genético, quanto à produtividade de grãos, foi estimado pelo método proposto por Vencovsky et al., e a significância verificada pelo teste de hipótese proposto neste trabalho. As substituições anuais de cultivares de milho são dinâmicas e nem sempre resultam em ganho genético para produtividade de grãos.Corn (Zea mays cultivars are usually replaced a few years after release. The objective of this study was to evaluate a proposed hypothesis test to determine if the annually cultivars replacements, in comparative field trials of recommended corn cultivars, result in genetic gain of grain yield. Comparative field trials of super early, early and normal corn cultivars were carried out during 1998/1999, 1999/2000, 2000/2001 and 2001/2002 grown seasons. The experimental design was a complete randomized block with three replications. Each plot had two rows of 5 m separated by 0.8 m. Grain yield genetic gain was estimated by the Vencovsky et al. method. Genetic gain significance was verified with the proposed hypothesis test. The annual replacement of corn cultivars is a dynamic process that not always result in genetic gain of grain yield.

  5. Innovation for maintenance technology improvements

    Science.gov (United States)

    Shives, T. R. (Editor); Willard, W. A. (Editor)

    1982-01-01

    A group of 34 submitted entries (32 papers and 2 abstracts) from the 33rd meeting of the Mechanical Failures Prevention Group whose subject was maintenance technology improvement through innovation. Areas of special emphasis included maintenance concepts, maintenance analysis systems, improved maintenance processes, innovative maintenance diagnostics and maintenance indicators, and technology improvements for power plant applications.

  6. Maintenance analysis method and operational feedback: a comprehensive maintenance management

    International Nuclear Information System (INIS)

    Mathieu Riou; Victor Planchon

    2006-01-01

    Full text of publication follows: Current periodic inspections program carried out on the COGEMA LOGISTICS casks is required by regulations and approved by the competent Authority. Thus, Safety and casks conformity to the according certificate of approval are guaranteed. Nonetheless, based on experience it appeared that some maintenance operations did not seem relevant or were redundant. Then, it was decided to rethink completely our maintenance program to reach the following objectives: - Set up the 'a minima' required inspection operations required to guarantee Safety and conformity to the certificate of approval, - Optimize criteria and periodicities of inspections taking into account: operational feedback, routine inspections carried out for each transport, regulations, environmental impact (ALARA, waste reduction,...), cost-effectiveness (reduction of cask's immobilization period,...). - Set up a maintenance program in Safety Analysis Reports that: stands alone (no need to check the specification or the certificate of approval to have the complete list of inspections mandatory to guarantee Safety), gives objectives instead of means of controls. This approach needs then to be re-evaluated by the competent Authority. Study's scope has been limited to the TN TM 12 cask family which is intensely used. COGEMA LOGISTICS has a high operational feedback on these casks. After Authority agreement, and in accordance with its requirements, study will then be extended to the other casks belonging to the COGEMA LOGISTICS cask fleet. Actually, the term 'maintenance' is linked to 'Base maintenance' and 'Main maintenance' and implicitly means that the cask is immobilized for a given period. To emphasize the modifications, the term 'maintenance' is no longer used and is substituted by 'periodic upkeep'. By changing the name, COGEMA LOGISTICS wants to emphasize that: some operations can for instance be realized while the cask is unloaded, periodicities are thought in terms of

  7. 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...

  8. Implementation and maintenance of patient navigation programs linking primary care with community-based health and social services: a scoping literature review.

    Science.gov (United States)

    Valaitis, Ruta K; Carter, Nancy; Lam, Annie; Nicholl, Jennifer; Feather, Janice; Cleghorn, Laura

    2017-02-06

    Since the early 90s, patient navigation programs were introduced in the United States to address inequitable access to cancer care. Programs have since expanded internationally and in scope. The goals of patient navigation programs are to: a) link patients and families to primary care services, specialist care, and community-based health and social services (CBHSS); b) provide more holistic patient-centred care; and, c) identify and resolve patient barriers to care. This paper fills a gap in knowledge to reveal what is known about motivators and factors influencing implementation and maintenance of patient navigation programs in primary care that link patients to CBHSS. It also reports on outcomes from these studies to help identify gaps in research that can inform future studies. This scoping literature review involved: i) electronic database searches; ii) a web site search; iii) a search of reference lists from literature reviews; and, iv) author follow up. It included papers from Canada, the United States, the United Kingdom, Australia, New Zealand, and/or Western Europe published between January 1990 and June 2013 if they discussed navigators or navigation programs in primary care settings that linked patients to CBHSS. Of 34 papers, most originated in the United States (n = 29) while the remainder were from the United Kingdom, Canada and Australia. Motivators for initiating navigation programs were to: a) improve delivery of health and social care services; b) support and manage specific health needs or specific population needs, and; c) improve quality of life and wellbeing of patients. Eleven factors were found to influence implementation and maintenance of these patient navigation programs. These factors closely aligned with the Diffusion of Innovation in Service Organizations model, thus providing a theoretical foundation to support them. Various positive outcomes were reported for patients, providers and navigators, as well as the health and social

  9. Reliability-Centered Maintenance

    Science.gov (United States)

    1978-12-29

    C. Mentzer, who directed khe pioneering studies of maintenance policy at United Airlines, and to the Federal Aviation Administration for creating...ANALYSIS 425 D-3 INFORMATION SCIENCi AND DECISION ANALYSIS 427 D-4 MAINTENANCE THEORY AND PHILOSOPHY 430 D-5 MAINTENANCE APPLUCATIONS 436 D-6 A GUIDE...occupants N Operational consequences, which involve an indirect economic loss as well as the direct cost of repair l Nonoperational consequences, which

  10. 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

  11. 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

  12. 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.)

  13. The effect of maintenance policy violations

    NARCIS (Netherlands)

    Rijsdijk, Christiaan; Tinga, Tiedo

    2014-01-01

    Motivation Maintenance policy assessments usually rely on expert judgement. We seek for some history based validation. Organisations may use our inference to assess risks of maintenance policy violations. Approach We depart from the arbitrary viewpoint that decisions have observable effects. We

  14. VEHICLE REPAIR AND MAINTENANCE COSTS IN NIGERIA ...

    African Journals Online (AJOL)

    A standard model was established for the prediction of repair and maintenance costs of vehicles in a non-profit making government parastatal. The model was derived based on data collected over a ten year period from a non-profit making government parastatal, and it predicts repair and maintenance costs as a linear ...

  15. 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

  16. 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...

  17. 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)

  18. 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...

  19. Estado nutricional e ganho de peso interdialítico de pacientes com doença renal crônica em hemodiálise

    OpenAIRE

    Ferraz,Sanzia Francisca; Freitas,Ana Tereza Vaz de Souza; Vaz,Inaiana Marques Filizola; Campos,Marta Isabel Valente Andrade Morais; Peixoto,Maria do Rosário Gondim; Pereira,Edna Regina Silva

    2015-01-01

    ResumoIntrodução:O estado nutricional (EN) de pacientes em hemodiálise (HD) é motivo de preocupação e de desafio. A desnutrição é comum nestes pacientes e relaciona-se com pior prognóstico clínico.Objetivos:Avaliar a associação entre o EN e o ganho de peso interdialítico (GPID) de pacientes com doença renal crônica (DRC) em hemodiálise (HD).Métodos:Estudo transversal realizado com 322 pacientes maiores de 18 anos. O EN foi avaliado por meio do índice de massa corporal (IMC), percentual de gor...

  20. Estudo de correlação entre lesões ao abate e ganho de peso diário de suínos

    OpenAIRE

    Marcos Horacio Rostagno

    1995-01-01

    Realizou-se ao abate, o exame de lesões pulmonares, nasais, hepáticas e entéricas, em 164 suínos mestiços, sendo 88 machos castrados e 76 fêmeas, provenientes de um rebanho de produção comercial, localizado no município de Ponte Nova/MG. Os amimais foram identificados individualmente, quanto ao sexo, à idade e ao peso vivo, para o cálculo do ganho de peso diário total. Após a colheita dos dados, estudou-se a existência de correlação entre a freqüência e a severidade das lesões observadas, e o...

  1. Recreational Vehicle Maintenance and Repair. COM-LINK. Competency Based Vocational Curricula with Basic Skills and Academic Linkages.

    Science.gov (United States)

    Felice, Michael

    This competency-based module uses the Ocean County (New Jersey) Vocational-Technical Schools curriculum-infused model for infusing basic skills instruction into vocational education. The model demonstrates the relationship of vocational skills to communication, mathematics, and science. The document begins with a philosophy statement; preface; a…

  2. Influência do ângulo de incidência nos ganhos de calor solar através de materiais transparentes

    Directory of Open Access Journals (Sweden)

    Joaquim Pizzutti dos Santos

    Full Text Available Este trabalho apresenta uma equação genérica que relaciona a variação do Fator Solar com o ângulo de incidência. As curvas resultantes desta variação, para vidros e outros materiais transparentes, foram obtidas a partir de experimentos de espectrofotometria para reflexão e transmissão, realizados para diferentes ângulos de incidência. Desta forma, foram identificados grupos de materiais com comportamento semelhante de variação do Fator Solar em função do ângulo. Para cada um dos grupos foi definido um material de referência, com valores de Fator Solar representando o comportamento médio do grupo. Para estes materiais foram obtidas equações gerais da curva de variação do Fator Solar, que permite calcular o ganho de calor solar total considerando a variação do ângulo de incidência da radiação ao longo de um período de tempo. O valor desses ganhos para qualquer material do mesmo grupo pode ser obtido aplicando um coeficiente de correção, que é o valor do Fator Solar para a incidência normal do material considerado. Os valores para esse coeficiente são propostos neste trabalho para um grande número de materiais ou podem ser obtidos a partir de catálogos.

  3. Development of marker-based tracking methods for augmented reality applied to NPP maintenance work support and its experimental evaluation

    International Nuclear Information System (INIS)

    Ishii, H.; Fujino, H.; Bian, Z.; Sekiyama, T.; Shimoda, H.; Yoshikawa, H.

    2006-01-01

    In this study, two types of marker-based tracking methods for Augmented Reality have been developed. One is a method which employs line-shaped markers and the other is a method which employs circular-shaped markers. These two methods recognize the markers by means of image processing and calculate the relative position and orientation between the markers and the camera in real time. The line-shaped markers are suitable to be pasted in the buildings such as NPPs where many pipes and tanks exist. The circular-shaped markers are suitable for the case that there are many obstacles and it is difficult to use line-shaped markers because the obstacles hide the part of the line-shaped markers. Both methods can extend the maximum distance between the markers and the camera compared to the legacy marker-based tracking methods. (authors)

  4. Establishment and maintenance of a coal sample bank and data base. Final report, April 8, 1988--September 28, 1993

    Energy Technology Data Exchange (ETDEWEB)

    Davis, A.; Glick, D.C.

    1993-11-01

    This DOE contract continued support for the DOE Coal Sample Bank and Data Base at Penn State. At the beginning of the contract, a new type of container was evaluated for long-term storage of coal samples ranging in quantity from a few grams to over 10 kg (22 lbs). Gieseler fluid behavior, oxidation of pyrite to sulfates, loss of heating value, and other properties were monitored over time. Based on preliminary results, these foil and polyethylene laminate bags were believed to be a significant improvement over the drums, buckets and cans previously used. Use of the bags was therefore instituted with DECS-1, the first sample collected under the contract. Twenty-two DECS samples were collected, ranging in rank from lignite to anthracite and representing the five most productive coal provinces of the US. Over 6500 containers of DECS samples were created under the contract and 750 containers of 34 PSOC samples are supported by the contract. Each sample was characterized by proximate and ultimate analysis, petrographic (vitrinite reflectance and maceral) analysis, physical and thermoplastic testing, and inorganic element analysis. The resulting data, and geologic data on each sample, were entered in a data base which can be used to produce a formatted five-page or one-page printout for each sample. An interactively operated data base can be searched, sorted or summarized to produce tables of selected data or to identify samples meeting a requestor`s criteria. During the period covered, 2,313 printouts, and 204 special data reports resulting in distribution of data on 34,086 samples, were provided on request.

  5. A Data Base Management System for Clinical and Epidemiologic Studies In Systemic Lupus Erythematosus: Design and Maintenance

    OpenAIRE

    Kosmides, Victoria S.; Hochberg, Marc C.

    1984-01-01

    This report describes the development, design specifications, features and implementation of a data base management system (DBMS) for clinical and epidemiologic studies in SLE. The DBMS is multidimensional with arrays formulated across patients, studies and variables. The major impact of this DBMS has been to increase the efficiency of managing and analyzing vast amounts of clinical and laboratory data and, as a result, to allow for continued growth in research productivity in areas related t...

  6. Computer-Based Training Development and Guidance for the Army’s Unmanned Aviation Systems Maintenance Training Division

    Science.gov (United States)

    2017-08-01

    American Psychologist , 63(8), 760-769. 7 Mayer, R. E. (2014). Research-based principles for designing multimedia instruction. Retrieved from...for the design of multimedia instruction. American Psychologist , 760-769. 5Mayer, R. E., & Moreno, R. (2003). Nine ways to reduce cognitive load...in multimedia learning. Educational Psychologist , 31(1), 43-52. 6Gasser, M., Boeke, J., Haffernan, M., & Tan, R. (2005). Influence of font type

  7. Designing evidence and theory-based ICT tools for weight loss maintenance: the H2020 NoHoW toolkit

    Directory of Open Access Journals (Sweden)

    Marta M Marques

    2015-11-01

    Conclusion: This presentation will provide an overview of the process of development of the NoHoW TK focusing on the foundations, the TK content, and the results from a pilot user-testing and will be discussing the contribution of a systematic approach to the development of ICT solutions based on theory, evidence, and user-testing, to the advancement of the science of behavior change and implementation of sustainable solutions to WLM across Europe.

  8. Achieving long-term weight maintenance in Mexican-American adolescents with a school-based intervention.

    Science.gov (United States)

    Johnston, Craig A; Moreno, Jennette P; Gallagher, Martina R; Wang, Jing; Papaioannou, Maria A; Tyler, Chermaine; Foreyt, John P

    2013-09-01

    This study evaluated 24-month outcomes of a school-based intensive lifestyle weight management program targeting overweight Mexican-American adolescents. We recruited a total of 71 adolescents (32 males; 45.1%) between the ages of 10 and 14 years, at or above the 85th percentile for body mass index (BMI). Participants were randomized to a 6-month instructor-led intervention (ILI) or a self-help (SH) program. Both interventions were aimed at modifying eating and physical activity behaviors using behavior modification strategies. We assessed changes in participants' standardized BMI and BMI percentile at baseline, 1, and 2 years. Repeated-measures analyses showed that ILI participants showed significantly greater decreases in standardized BMI at 1 and 2 years (F = 8.58, p school-based intervention resulted in improved weight outcomes in overweight Mexican-American adolescents and results were maintained over 2 years. Copyright © 2013 Society for Adolescent Health and Medicine. Published by Elsevier Inc. All rights reserved.

  9. Maintenance optimization with AREVA

    Energy Technology Data Exchange (ETDEWEB)

    Kostroun, Frank; Herzing, Karl-Heinz; Buschart, Rufus [AREVA NP GmbH, Erlangen (Germany)

    2009-04-15

    Driven by the economic expectations of an energy market that becomes increasingly unregulated, the optimization of the maintenance in a nuclear power plant is a more demand practice. This paper describes on three exemplary product lines of AREVA, how AREVA can support its customers optimizing its maintenance.

  10. Maintenance Trades Guidelines

    Science.gov (United States)

    Weidner, Theodore J.

    2008-01-01

    In 2002, APPA published "Maintenance Staffing Guidelines for Educational Facilities," the first building maintenance trades staffing guideline designed to assist educational facilities professionals with their staffing needs. addresses how facilities professionals can determine the appropriate size and mix of their organization. Contents…

  11. Maintenance improvement program

    International Nuclear Information System (INIS)

    Derbonne, D.R.; Plunkett, T.F.; Simpson, J.R.

    1989-01-01

    During fuel cycle 1 at River Bend station, considerable effort was expended to reduce corrective maintenance work orders (MWOs) to <1,000. This was done by complementing the plant staff with costly contract personnel. Coming out of the first refueling outage, most contract personnel were released. The change in MWO backlog started a steady rise. It became readily apparent that to avoid costly contract staff time, a maintenance improvement program (MIP) was necessary. The MIP Was primarily directed at two areas: crew efficiency improvements and improved preplanned MWO packages. The overall effect of the MIP was to achieve significant productivity improvements with reduced operation and maintenance cost by providing frequent accountability to all levels of maintenance supervision. The MIP also produced a feeling of pride among the maintenance department employees that had not really existed before. This was the best benefit of all

  12. Chinese Herbal Decoction Based on Syndrome Differentiation as Maintenance Therapy in Patients with Extensive-Stage Small-Cell Lung Cancer: An Exploratory and Small Prospective Cohort Study

    Directory of Open Access Journals (Sweden)

    Rui Liu

    2015-01-01

    Full Text Available Objective. To investigate the treatment effect and treatment length of Chinese herbal decoction (CHD as maintenance therapy on patients with extensive-stage small-cell lung cancer (ES-SCLC and to reflect the real syndrome differentiation (Bian Zheng practices of traditional Chinese medicine (TCM. Patients and Methods. Different CHDs were prescribed for each patient based on syndrome differentiation. The length of CHD treatment was divided into two phases for analyzing progression-free survival (PFS and postprogression survival (PPS. Results. Three hundred and fifty-seven CHDs were prescribed based on syndrome differentiation during the study period. Median PFS was significantly longer in patients who received CHD >3 months than patients who received CHD ≤3 months in the first phase (8.7 months versus 4.5 months; hazard ratio (HR, 0.52; 95% confidence interval (CI, 0.41–0.99; P=0.0009. Median PPS was significantly longer in patients who received CHD >7 months than patients who received CHD ≤7 months in the second phase (11.7 months versus 5.1 months; HR, 2.32; 95% CI, 1.90–2.74; P=0.002. Conclusion. CHD could improve PFS and PPS, which are closely related to treatment time and deepness of response of first-line therapy. In addition, CHD could improve body function and keep patients in a relatively stable state.

  13. Does body size of dairy cows, at constant ratio of maintenance to production requirements, affect productivity in a pasture-based production system?

    Science.gov (United States)

    Hofstetter, P; Steiger Burgos, M; Petermann, R; Münger, A; Blum, J W; Thomet, P; Menzi, H; Kohler, S; Kunz, P

    2011-12-01

    This study compared productivity of dairy cows with different body weight (BW), but a constant ratio of maintenance to production requirements in their first lactation, in a pasture-based production system with spring calving. Two herds, Herd L (13 and 14 large cows in 2003 and 2004 respectively; average BW after calving, 721 kg) and Herd S (16 small cows in both years; 606 kg) [Correction added after online publication 14 January 2011: 16 small cows in both years; 621 kg was changed to 16 small cows in both years; 606 kg], all in their second or following lactations, were each allocated 6 ha of pasture and rotationally grazed on 10 parallel paddocks with equal herbage offer and nutritional values. Winter hay, harvested from the same pastures, was offered ad libitum in the indoor periods in a tied stall barn. Each herd received, per lactation and year, approximately 2000 kg dry matter (DM) of concentrates and of fodder beets, equally distributed to every individual. Indoors, the L-cows ingested more DM than the S-cows (18.7 vs. 16.3 kg DM/cow per day; p pasture (17.9 vs. 15.5 kg DM/cow per day; p pasture-based forage. © 2010 Blackwell Verlag GmbH.

  14. Genetic algorithm-based optimization of testing and maintenance under uncertain unavailability and cost estimation: A survey of strategies for harmonizing evolution and accuracy

    International Nuclear Information System (INIS)

    Villanueva, J.F.; Sanchez, A.I.; Carlos, S.; Martorell, S.

    2008-01-01

    This paper presents the results of a survey to show the applicability of an approach based on a combination of distribution-free tolerance interval and genetic algorithms for testing and maintenance optimization of safety-related systems based on unavailability and cost estimation acting as uncertain decision criteria. Several strategies have been checked using a combination of Monte Carlo (simulation)--genetic algorithm (search-evolution). Tolerance intervals for the unavailability and cost estimation are obtained to be used by the genetic algorithms. Both single- and multiple-objective genetic algorithms are used. In general, it is shown that the approach is a robust, fast and powerful tool that performs very favorably in the face of noise in the output (i.e. uncertainty) and it is able to find the optimum over a complicated, high-dimensional nonlinear space in a tiny fraction of the time required for enumeration of the decision space. This approach reduces the computational effort by means of providing appropriate balance between accuracy of simulation and evolution; however, negative effects are also shown when a not well-balanced accuracy-evolution couple is used, which can be avoided or mitigated with the use of a single-objective genetic algorithm or the use of a multiple-objective genetic algorithm with additional statistical information

  15. Long-Term Weight-Loss Maintenance by a Meal Replacement Based Weight Management Program in Primary Care.

    Science.gov (United States)

    Kruschitz, Renate; Wallner-Liebmann, Sandra; Lothaller, Harald; Luger, Maria; Ludvik, Bernhard

    2017-01-01

    Structured obesity treatment programs at primary care level are becoming increasingly important. However, evidence from current treatment approaches in the long term is lacking. In view of this fact we evaluated a standardized, meal replacement-based weight loss program (myLINE®; AENGUS, Graz, Austria) according to the currently applicable guidelines. Data of overweight and obese individuals (n = 70) who participated at least 36 months in the program were analyzed. Data were collected at baseline (T0) as well as after 1, 3, 6, 12, 24, and 36 (T1-T36) months. Body composition was measured by conventional anthropometry and bioelectrical impedance analysis. Compared to T0, a maximum weight, BMI, fat mass, absolute body cell mass (BCM) reduction and an increase of relative BCM could be seen at T6. Subsequently, the findings reveal a significant reduction of body weight and body fat and a satisfying development of body cell mass during the observation period of 36 months. The evaluated program complies with national and international guidelines for the therapy of obesity in adults and is efficient and meaningful for a long-term therapeutic use in primary care.. © 2017 The Author(s) Published by S. Karger GmbH, Freiburg.

  16. Long-Term Weight-Loss Maintenance by a Meal Replacement Based Weight Management Program in Primary Care

    Directory of Open Access Journals (Sweden)

    Renate Kruschitz

    2017-04-01

    Full Text Available Objective: Structured obesity treatment programs at primary care level are becoming increasingly important. However, evidence from current treatment approaches in the long term is lacking. In view of this fact we evaluated a standardized, meal replacement-based weight loss program (myLINE®; AENGUS, Graz, Austria according to the currently applicable guidelines. Methods: Data of overweight and obese individuals (n = 70 who participated at least 36 months in the program were analyzed. Data were collected at baseline (T0 as well as after 1, 3, 6, 12, 24, and 36 (T1-T36 months. Body composition was measured by conventional anthropometry and bioelectrical impedance analysis. Results: Compared to T0, a maximum weight, BMI, fat mass, absolute body cell mass (BCM reduction and an increase of relative BCM could be seen at T6. Subsequently, the findings reveal a significant reduction of body weight and body fat and a satisfying development of body cell mass during the observation period of 36 months. Conclusion: The evaluated program complies with national and international guidelines for the therapy of obesity in adults and is efficient and meaningful for a long-term therapeutic use in primary care..

  17. Statistical State Dynamics Based Study of the Role of Nonlinearity in the Maintenance of Turbulence in Couette Flow

    Science.gov (United States)

    Farrell, Brian; Ioannou, Petros; Nikolaidis, Marios-Andreas

    2017-11-01

    While linear non-normality underlies the mechanism of energy transfer from the externally driven flow to the perturbation field, nonlinearity is also known to play an essential role in sustaining turbulence. We report a study based on the statistical state dynamics of Couette flow turbulence with the goal of better understanding the role of nonlinearity in sustaining turbulence. The statistical state dynamics implementations used are ensemble closures at second order in a cumulant expansion of the Navier-Stokes equations in which the averaging operator is the streamwise mean. Two fundamentally non-normal mechanisms potentially contributing to maintaining the second cumulant are identified. These are essentially parametric perturbation growth arising from interaction of the perturbations with the fluctuating mean flow and transient growth of perturbations arising from nonlinear interaction between components of the perturbation field. By the method of selectively including these mechanisms parametric growth is found to maintain the perturbation field in the turbulent state while the more commonly invoked mechanism associated with transient growth of perturbations arising from scattering by nonlinear interaction is found to suppress perturbation variance. Funded by ERC Coturb Madrid Summer Program and NSF AGS-1246929.

  18. Layered Nano-TiO2 Based Treatments for the Maintenance of Natural Stones in Historical Architecture.

    Science.gov (United States)

    Gherardi, Francesca; Goidanich, Sara; Dal Santo, Vladimiro; Toniolo, Lucia

    2018-02-09

    Layered treatments of natural stones based on dispersions of experimental nano-TiO 2 and commercial TEOS showing photocatalytic and self-cleaning properties were set up and tested. To enhance nano-TiO 2 efficacy, a surface pre-treatment with tetraethyl orthosilicate was proposed to avoid the penetration of NPs into the crystalline porous substrates and to improve their adhesion to the stone. Two treatment applications (wet-on-wet and wet-on-dry) were compared, showing different results. A strong interaction Si-O-Ti was the key factor for the successful treatment, leaving the band gap and relevant properties of nano-TiO 2 unaltered. The layered treatments were tested on a porous calcarenite (Noto stone) and a very compact marble (Carrara marble). The combined SiO 2 -nano-TiO 2 treatments can find application in suitable cases where a surface consolidation is needed, ensuring a depolluting and self-cleaning durable activity. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  19. 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)

  20. 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

  1. An Improved Method for Dynamic Measurement of Deflections of the Vertical Based on the Maintenance of Attitude Reference

    Directory of Open Access Journals (Sweden)

    Dongkai Dai

    2014-09-01

    Full Text Available A new method for dynamic measurement of deflections of the vertical (DOV is proposed in this paper. The integration of an inertial navigation system (INS and global navigation satellite system (GNSS is constructed to measure the body’s attitude with respect to the astronomical coordinates. Simultaneously, the attitude with respect to the geodetic coordinates is initially measured by a star sensor under quasi-static condition and then maintained by the laser gyroscope unit (LGU, which is composed of three gyroscopes in the INS, when the vehicle travels along survey lines. Deflections of the vertical are calculated by using the difference between the attitudes with respect to the geodetic coordinates and astronomical coordinates. Moreover, an algorithm for removing the trend error of the vertical deflections is developed with the aid of Earth Gravitational Model 2008 (EGM2008. In comparison with traditional methods, the new method required less accurate GNSS, because the dynamic acceleration calculation is avoided. The errors of inertial sensors are well resolved in the INS/GNSS integration, which is implemented by a Rauch–Tung–Striebel (RTS smoother. In addition, a single-axis indexed INS is adopted to improve the observability of the system errors and to restrain the inertial sensor errors. The proposed method is validated by Monte Carlo simulations. The results show that deflections of the vertical can achieve a precision of better than 1″ for a single survey line. The proposed method can be applied to a gravimetry system based on a ground vehicle or ship with a speed lower than 25 m/s.

  2. 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...

  3. 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

  4. 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

  5. Mobile network maintenance (GSM)

    CERN Multimedia

    IT Department

    2009-01-01

    Maintenance work will be carried out on the CERN mobile network infrastructure (GSM) on the 23 and 24 July from 6 p.m. to 6 a.m. in order to replace discontinued equipment and to increase the bandwidth capacity of the GSM mobile network. All CERN GSM emitters (40 units) will be moved one by one to the new infrastructure during the maintenance. The call of a user connected to an emitter at the time of its maintenance will be cut off. However, the general overlapping of the GSM radio coverage should mean that users are able immediately to call again should their call be interrupted. IT/CS/CS

  6. Operations and Maintenance Manual for Expanded Bioventing System, Site SS-41, Former Building Number 93 (Fuel Pumping Station Number 3), Charleston Air Force Base, Charleston, South Carolina

    National Research Council Canada - National Science Library

    1997-01-01

    This Operations and Maintenance (O&M) Manual has been created as a guide for monitoring and maintaining the performance of the expanded bioventing blower systems and vent well plumbing at Site SS-41 (Former Building...

  7. 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....

  8. Progress with the national infrastructure maintenance strategy

    CSIR Research Space (South Africa)

    Wall, K

    2008-07-01

    Full Text Available The National Infrastructure Maintenance Strategy was approved by Cabinet in August 2006. This strategy sets overarching policy for sector-based initiatives, and describes the framework for a coordinated programme of actions. Simultaneous...

  9. Maintenance training - a modern necessity

    International Nuclear Information System (INIS)

    Bushall, W.

    1987-01-01

    In recent years, there has been an increase in technically advanced systems and equipment and a need for highly skilled and knowledgeable maintenance technicians to maintain them. To implement an effective training program, training groups' and plant staffs' key to success must be cooperation and creativity. This paper deals with plant staff interface and how to effectively conduct performance-based training while holding the line on costs. This paper includes cost effective and innovative measures to produce performance-based training for maintenance disciplines including: Using the plants staff as a resource as subject matter experts in the development and verification of training materials. Using the plant staff as a resource for the construction of training aids. Using salvage and surplus to produce high quality, low cost training aids. Using cutaways for better understanding of he theory of equipment operation. These cost saving practices are currently being used at Gulf States Utilities' River Bend Nuclear Station

  10. Estimativas do Consumo e do Ganho de Peso de Bovinos, em Condições Brasileiras Estimates of the Intake and Weight Gain of Cattle at Brazilian Conditions

    Directory of Open Access Journals (Sweden)

    Edilson Rezende Cappelle

    2001-12-01

    Full Text Available Avaliou-se a predição do consumo de matéria seca e do ganho de peso diário de bovinos feita pelo Cornell Net Carbohydrate and Protein System (CNCPS para as condições brasileiras. Foram utilizadas, neste trabalho, como fonte de dados, algumas teses defendidas no Departamento de Zootecnia da Universidade Federal de Viçosa, que continham resultados referentes ao consumo e ganho de peso dos animais. Os dados disponíveis foram testados pelo CNCPS para comparar os consumos e os ganhos de peso observados e estimados. Os consumos observados variaram muito entre as categorias animais e foram sempre subestimados pelo CNCPS. As melhores predições de consumo foram para os novilhos abatidos aos 405 kg e 500 kg de peso vivo (PV, com maior porcentagem de concentrado na dieta. A equação de regressão Y OBS = 2,27107 + 0,96747 X CNCPS (r²=0,92; PThe dry matter intake and daily weight gain prediction of cattle by Cornell Net Carbohydrate and Protein System (CNCPS for Brazilian conditions were evaluated. Several published thesis from Departamento de Zootecnia da Universidade Federal de Viçosa were used as a data source for this work, which contain results referent to dry matter intake and daily weight gain of the animals. The available data were tested by CNCPS to compare the estimate and absorved dry matter intake and daily weight gain. The observed dry matter intake ranged among the animal categories and was always underestimated by CNCPS. The best dry matter intake were predicted for steers slaughtered at 405 and 500 kg LW with higher concentrate level in the diet. The regression equation Y OBS = 2.27107 + 0.96747 X CNCPS (r² = 0.92; P<0.01 showed the same tendency as the ideal relation line (Y=X and could be used to estimate the dry matter intake from the CNCPS predicted values. The observed daily weight gain when compared to the CNCPS predicted values present high variations, and the best daily weight gain was predicted for steers slaughtered

  11. Evaluation of maintenance strategies.

    Science.gov (United States)

    2013-11-01

    In the mid1990s, the Arizona Department of Transportation (ADOT) initiated the Maintenance Cost : Effectiveness study (SPR 371) with the development of plans and an experiment design to evaluate the : effectiveness of a variety of asphalt pavement...

  12. 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

  13. Excellence through maintenance mastering

    International Nuclear Information System (INIS)

    Lamarche, M.; Guillot, M.; Monier, M.

    1987-01-01

    To improve the overall availability factor of nuclear power plants you have to cut either the forced outage role and the planned outage time or you need to reduce simultaneously the failures and the efforts devoted to avoiding them. Among other results, this goal leads to a decrease in the number of real or anticipated problems. Electricite de France policy, in this matter, is to focus on decreasing the compoents' maintenance needs through a comprehensive modification program, targeted to eliminating the weak points as revealed by the operation. Thereby one may reach, for simple equipment, a nearly maintenance-free condition in which the only maintenance needed is surveillance, which provides assurance that everything is operating properly. A good example of this type of equipment is the family of static components, drums, and pipes whose corrective maintenance is almost nil when their initial condition is good

  14. Licencing and Training Reform in the Australian Aircraft Maintenance Industry

    Science.gov (United States)

    Hampson, Ian; Fraser, Doug

    2016-01-01

    The training and licencing of aircraft maintenance engineers fulfils a crucial protective function since it is they who perform and supervise aircraft maintenance and certify that planes are safe afterwards. In Australia, prior to training reform, a trades-based system of aircraft maintenance engineer training existed in an orderly relation with…

  15. Evaluation of In-House versus Contract Computer Hardware Maintenance

    International Nuclear Information System (INIS)

    Wright, H.P.

    1981-09-01

    The issue of In-House versus Contract Computer Hardware Maintenance is one which every organization who uses computers must resolve. This report discusses the advantages and disadvantages of both approaches to computer maintenance, the costs involved (based on the current AGNS computer inventory), and the AGNS maintenance experience to date. A recommendation on an appropriate approach for AGNS is made

  16. Balancing preventive and corrective maintenance in Cernavoda Unit 1 NPP

    International Nuclear Information System (INIS)

    Riedel, M.; Marinescu, S.

    2000-01-01

    The paper presents a short reminder of Romania's Cernavoda NPP entering commercial operation and a brief description of the CANDU-6 project on which Unit 1 is based. The short term objectives of the maintenance management, the status of the existing maintenance programmes as well as future predictable maintenance programmes are outlined together with the Government plan to complete the balance of NPP. (author)

  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. 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

  19. TFTR remote maintenance

    International Nuclear Information System (INIS)

    Bonanos, P.; Lontai, L.

    1977-01-01

    The Tokamak Fusion Test Reactor (TFTR) is the first tokamak designed to utilize tritium plasmas and achieve significant neutron yields. Tritium operations are scheduled for the early 1980's at the Princeton Plasma Physics Laboratory. Complex operations of unprecedented scale must be performed remotely. The design of TFTR and the maintenance system supporting it are developing in parallel. The nature of the problem and a proposed set of maintenance tools are described

  20. Remote maintenance development

    International Nuclear Information System (INIS)

    Zook, C.R.

    1979-01-01

    The concept of remote maintenance as it pertains to nuclear fuel fabrication facilities is quite unique. The future may require completely remote facilities where maintenance will be performed by hybrid manipulators/robots. These units will be capable of being preprogrammed for automatic operation or manually operated with the operator becoming a part of the closed loop control system. These robots will mesh television, computer control, and direct force feedback manual control in a usable new concept of robotics

  1. Physicians’ attitudes towards office-based delivery of methadone maintenance therapy: results from a cross-sectional survey of Nova Scotia primary-care physicians

    Directory of Open Access Journals (Sweden)

    Dooley Jessica

    2012-06-01

    Full Text Available Abstract Background Approximately 90,000 Canadians use opioids each year, many of whom experience health and social problems that affect the individual user, families, communities and the health care system. For those who wish to reduce or stop their opioid use, methadone maintenance therapy (MMT is effective and supporting evidence is well-documented. However, access and availability to MMT is often inconsistent, with greater inequity outside of urban settings. Involving community based primary-care physicians in the delivery of MMT could serve to expand capacity and accessibility of MMT programs. Little is known, however, about the extent to which MMT, particularly office-based delivery, is acceptable to physicians. The aim of this study is to survey physicians about their attitudes towards MMT, particularly office-based delivery, and the perceived barriers and facilitators to MMT delivery. Methods In May 2008, facilitated by the College of Physicians and Surgeons of Nova Scotia, a cross-sectional, e-mail survey of 950 primary-care physicians practicing in Nova Scotia, Canada was administered via the OPINIO on-line survey software, to assess the acceptability of office-based MMT. Logistic regressions, adjusted for physician sociodemographic characteristics, were used to examine the association between physicians’ willingness to participate in office-based MMT, and a series of measures capturing physician attitudes and knowledge about treatment approaches, opioid use, and methadone, as well as perceived barriers to MMT. Results Overall, 19.8% of primary-care physicians responded to the survey, with 56% who indicated that they would be willing to be involved in MMT under current or similar circumstances; however, willingness was associated with numerous attitudinal and systemic factors. The barriers to involvement in MMT that were frequently cited included a lack of training or experience in MMT, lack of support services, and potential

  2. Ganho de peso, consumo de ração e histologia de órgãos de leitões alimentados com rações contendo baixos níveis de fumonisina B1

    Directory of Open Access Journals (Sweden)

    Pollyana C.M.C. Souto

    2015-05-01

    Full Text Available Resumo:A fumonisina B1 (FB1 é um metabólito secundário produzido principalmente por Fusarium verticilioides em diversos tipos de alimentos, principalmente o milho, o qual constitui a base para composição de rações para várias espécies de animais domésticos. A FB1é particularmente tóxica para suínos, cujas manifestações clínicas são evidentes em animais expostos a altas concentrações de FB1 na ração (em geral, acima de 30mg/kg. No entanto, são escassos os estudos sobre os efeitos da FB1em suínos alimentados com rações contendo baixas concentrações de fumonisinas, as quais são mais prováveis de serem encontradas em condições de campo. O objetivo do estudo foi avaliar os efeitos da exposição de leitões a baixos níveis de FB1 na ração, durante 28 dias, sobre o ganho de peso, consumo de ração, peso relativo de órgãos e aspectos histológicos do baço, fígado, pulmões, rins e coração. Vinte e quatro leitões foram distribuídos em 4 grupos experimentais e alimentados com rações contendo 0mg (controle, 3,0mg, 6,0mg ou 9,0mg FB1/kg de ração. As diferentes dietas não afetaram (P>0,05 o ganho de peso e nem o peso relativo dos órgãos analisados. Não foram constatadas lesões macroscópicas ou histopatológicas no baço, fígado, rins e coração. No entanto, foram observadas lesões histopatológicas nos pulmões de todos os suínos alimentados com rações contaminadas com fumonisinas, indicando que nenhum dos níveis de FB1 usados no experimento poderia ser considerado como seguro para suínos. São necessários novos estudos sobre os mecanismos de ação tóxica da FB1 em suínos, sobretudo em condições de exposição prolongada a baixos níveis de contaminação na ração.

  3. Mechanical configuration and maintenance

    International Nuclear Information System (INIS)

    Brown, T.G.; Casini, G.; Churakov, G.F.

    1982-01-01

    The INTOR engineering design has been strongly influenced by considerations for assembly and maintenance. A maintenance philosophy was established at the outset of the conceptual design to insure that the tokamak configuration would be developed to accommodate maintenance requirements. The main features of the INTOR design are summarized in this paper with primary emphasis on the impact of maintenance considerations. The most apparent configuration design feature is the access provided for torus maintenance. Particular attention was given to the size and location of superconducting magnets and the location of vacuum boundaries. All of the poloidal field (PF) coils are placed outside of the bore of the toroidal field (TF) coils and located above and below an access opening between adjacent TF coils through which torus sectors are removed. A magnet structural configuration consisting of mechanically attached reinforcing members has been designed which facilitates the open access space for torus sector removal. For impurity control, a single null poloidal divertor was selected over a double null design in order to maintain sufficient access for pumping and maintenance of the collector. A double null divertor was found to severely limit access to the torus with the addition of divertor collectors and pumping at the top. For this reason, a single null concept was selected in spite of the more difficult design problems associated with the required asymmetric PF system and higher particle loadings

  4. Paratireoidectomia na doença renal crônica: efeitos no ganho de peso e na melhora da qualidade de vida

    Directory of Open Access Journals (Sweden)

    Henyse Gomes Valente-Da-Silva

    Full Text Available RESUMO Objetivo: avaliar o benefício de paratireoidectomia em pacientes submetidos à hemodiálise, em relação ao estado nutricional e bioquímico, composição corporal e a qualidade de vida. Métodos: estudo longitudinal envolvendo 28 adultos em programa de hemodiálise, com hiperparatireoidismo secundário grave, avaliados antes e um ano após a cirurgia. Critérios de inclusão: níveis de paratormônio dez vezes superior ao valor de referencia e doença renal crônica em programa de hemodiálise. O índice de massa corporal foi utilizado para classificação do estado nutricional. A bioimpedância elétrica para avaliação da composição corporal. A análise bioquímica incluiu dosagem de lipídios e marcadores do metabolismo ósseo. A qualidade de vida foi avaliada pelo questionário SF36 (Short Form Health Survey. Todos os pacientes foram submetidos à paratireoidectomia total com implante em antebraço. Resultados: houve ganho significativo de peso corporal (61,7 vs 66,0 kg; p<0,001, da massa celular corporal (22,0 vs 24,5 kg/m2; p=0,05 e da qualidade de vida (p=0,001 após a cirurgia. Com relação ao metabolismo ósseo, PTH intacto, cálcio, fósforo e fosfatase alcalina, se estabilizaram e houve melhora em parâmetros bioquímicos, tais como albumina e hemoglobina. Conclusão: a paratireoidectomia melhora a sobrevida em pacientes de hemodiálise e está associada a aumento de peso, ganho de massa óssea e melhoria na qualidade de vida.

  5. Influences of hand dominance on the maintenance of benefits after home-based modified constraint-induced movement therapy in individuals with stroke

    Directory of Open Access Journals (Sweden)

    Renata C. M. Lima

    2014-10-01

    Full Text Available Objective: To investigate the influence of hand dominance on the maintenance of gains after home-based modified constraint-induced movement therapy (mCIMT. Method: Aprevious randomized controlled trial was conducted to examine the addition of trunk restraint to the mCIMT. Twenty-two chronic stroke survivors with mild to moderate motor impairments received individual home-based mCIMT with or without trunk restraints, five times per week, three hours daily over two weeks. In this study, the participants were separated into dominant group, which had their paretic upper limb as dominant before the stroke (n=8, and non-dominant group (n=14 for analyses. The ability to perform unimanual tasks was measured by the Wolf Motor Function Test (WMFT and the Motor Activity Log (MAL, whereas the capacity to perform bimanual tasks was measured using the Bilateral Activity Assessment Scale (BAAS. Results: Analysis revealed significant positive effects on the MAL amount of use and quality of the movement scales, as well as on the BAAS scores after intervention, with no differences between groups. Both groups maintained the bimanual improvements during follow-ups (BAAS-seconds 0.1, 95% CI -10.0 to 10.0, however only the dominant group maintained the unilateral improvements (MAL-amount of use: 1.5, 95% CI 0.7 to 2.3; MAL-quality: 1.3, 95% CI 0.5 to 2.1. Conclusions: Upper limb dominance did not interfere with the acquisition of upper limb skills after mCIMT. However, the participants whose paretic upper limb was dominant demonstrated better abilities to maintain the unilateral gains. The bilateral improvements were maintained, regardless of upper limb dominance.

  6. Application and issues of online maintenance for equipment of nuclear power plants

    International Nuclear Information System (INIS)

    Higasa, Hisakazu

    2011-01-01

    The maintenance systems for long-term safety and repair costs reduction of equipment of nuclear power plants are stated. Planned maintenance contained the breakdown maintenance (BM) and the preventive maintenance, which consists of the time based maintenance (MBM) and the condition based maintenance (CBM). Explained are the characteristics of equipments, maintenance methods, maintenance solutions and the self-evaluation maintenance power, damage mechanism and solutions, and monitoring tools and application. Stated are the maintenance system and application of monitoring technology, periodical maintenance, application of diagnosis, vibration monitoring techniques, decision of vibration monitoring, and application of monitoring techniques for improvement of maintenance. Illustrated are realization of planned maintenance by reorganization of maintenance, a trend of maintenance of equipments, table of classified maintenance systems, change of maintenance program, maintenance data and investigation of damage mechanism, examples of self-evaluation maintenance power, examples of analysis of damage of parts of equipments, evaluation of rotating machines by vibration method, examples of results of diagnosis of bearing of rotating machines, online maintenance system of Asahi Kasei Engineering Corporation, degradation pattern of pomp, estimation of lifetime by total vibration and vibration on acceleration, and improvement of equipments. (S.Y.)

  7. Increasing the competitiveness of maintenance contract rates by using an alternative methodology for the calculation of average vehicle maintenance costs

    Directory of Open Access Journals (Sweden)

    Stephen Carstens

    2008-11-01

    Full Text Available Companies tend to outsource transport to fleet management companies to increase efficiencies if transport is a non-core activity. The provision of fleet management services on contract introduces a certain amount of financial risk to the fleet management company, specifically fixed rate maintenance contracts. The quoted rate needs to be sufficient and also competitive in the market. Currently the quoted maintenance rates are based on the maintenance specifications of the manufacturer and the risk management approach of the fleet management company. This is usually reflected in a contingency that is included in the quoted maintenance rate. An alternative methodology for calculating the average maintenance cost for a vehicle fleet is proposed based on the actual maintenance expenditures of the vehicles and accepted statistical techniques. The proposed methodology results in accurate estimates (and associated confidence limits of the true average maintenance cost and can beused as a basis for the maintenance quote.

  8. Influência de revestimentos comestíveis na redução de ganho de sólidos em jenipapos desidratados osmoticamente Influence of edible coatings in the reduction of solids uptake in osmotically dehydrated Jenipapos

    Directory of Open Access Journals (Sweden)

    Samara Alvachian Cardoso Andrade

    2007-03-01

    Full Text Available A desidratação osmótica é um processo que pode ser aplicado a frutos, para aumentar sua vida útil e, conseqüentemente, reduzir o percentual de perdas. Na aplicação deste processo em jenipapo, foi observada uma elevada incorporação de sólidos solúveis, considerada desvantajosa por reduzir a similaridade entre o produto e o fruto "in natura". Neste trabalho, foram empregados revestimentos comestíveis à base de alginato e pectina de baixa metoxilação, com o objetivo de diminuir a transferência de massa, cuja eficácia foi avaliada em jenipapos adquiridos nos supermercados da Região metropolitana do Recife, nas condições em que são comercializados. A pesquisa foi desenvolvida em duas etapas. A primeira, por meio de planejamento fatorial fracionário 2(3-1, com o objetivo de estudar a influência das coberturas, constituída por três tratamentos: A (frutos sem revestimento; B (frutos cobertos com alginato; e C (frutos cobertos com pectina. A segunda, por planejamento fatorial 2³, para determinar a influência das variáveis independentes, temperatura, tipo de cobertura e geometria sobre a perda de umidade, ganho de solutos, variação de peso e taxa de DEI (Dehydration Efficiency Index. Os resultados obtidos na 1ª etapa evidenciaram que: as coberturas foram eficientes na redução da incorporação de solutos, bem como no aumento de perda de umidade; os maiores DEI, em ambas as coberturas, foram obtidos a 50 °Brix, sendo o máximo a 30 °C e geometria representada por um quarto de fruta. Na 2ª etapa, foram confirmados maior influência da geometria sobre a perda de umidade e o ganho de solutos e das coberturas sobre a variação de peso e perda de umidade. Foi constatado que a temperatura exerce decisiva influência sobre as demais variáveis, com exceção dos DEI. Os resultados permitiram concluir que os menores ganhos de solutos, associados a uma satisfatória perda de umidade, foram obtidos com cobertura de alginato

  9. Building relationships for better maintenance.

    Science.gov (United States)

    Lee, Hackman Hon Yin; Scott, David

    2009-02-01

    Effective management of building maintenance is a vital ingredient in ensuring a high quality built environment for any building's occupiers. However, maintenance is not high on the list of priorities for most organisations. Communication between top management personnel looking at maintenance issues from a strategic standpoint and maintenance staff considering them at an operational level is often not as good as it should be. When planning maintenance activities maintenance personnel often draw too heavily on their technical experience and expertise without taking sufficient account of wider organisational objectives or consulting effectively with top management. Senior managers also regularly complain about lack of managerial input from maintenance departments. Such barriers contribute to communication difficulties between top management at a strategic level and maintenance personnel at an operational level. Identifying where the key differences lie in senior managers' and maintenance personnel's viewpoints on maintenance strategy can prove invaluable in achieving some convergence of opinions and optimising the efficiency of the overall building maintenance process.

  10. Maintenance and Outage Management Assessment (MOMA)

    International Nuclear Information System (INIS)

    2005-01-01

    a small team of experienced nuclear experts/specialists in the world. It can be requested for a single area or multiple ones, such as a) In-Service Inspection program review and optimization, including inspection qualification and risk informed inspection, b) maintenance program optimization by means of equipment reliability, performance based approach, risk informed on-line maintenance, condition based maintenance, c) outage improvement be means of streamlined integration of technologies and process, work planning and scheduling, plant modifications and configuration control, indicators and operating experience feedback system, safety culture, outsourcing and contract management, and spare parts

  11. Predictive maintenance: A new approach in maintenance of nuclear power plants

    International Nuclear Information System (INIS)

    Benvenuto, F.; Ferrari, L.

    2005-01-01

    The maintenance services for a Nuclear Power Plant are in general aimed at reaching the following goals: - Increase component availability and consequently decrease intervention frequency; - Reduce unexpected costs from unexpected repairs; - Progressively decrease the time of each intervention; - Improve the spare parts supply efficiency; - Improve spare parts and consumable warehouse managing; - Decrease maintenance costs. Most of the currently used maintenance activities refer to run-to-failure or preventive approaches: - Run-to-failure or Corrective Maintenance means that work is only carried out when a component or system is faulty and unable to perform its critical function. Non critical components such as filters or components with spare may be maintained in this way; - Preventive or Scheduled Maintenance involves a regular pre-set schedule programme of maintenance work. Programme outlined by the manufacturer of the component in question based on the design life of the component and based on past experience by operation. One step further than Preventive Maintenance is represented by Predictive Maintenance. Whereas Preventive Maintenance bases its schedules on past performance data, a predictive system acquires condition data from the machine to be maintained whilst the machine is in operation. The information obtained from this analysis indicates the condition in real time, provides a diagnosis of wear and shows any trend towards critical conditions. Predictive maintenance mainly consists of the following interventions: - Lubricant analysis; - Collection / analysis of functional parameters, such as motor absorption, flow rate, pressure, temperature, noise, vibration of rotating equipment, thermal efficiency, etc; - Periodical test of lifting systems; - Other operations to acquire sensitive equipment parameters. Predictive Maintenance can reduce the accidental intervention and extend the components life, and, in the end, is increasing the global availability

  12. Differing antidepressant maintenance methodologies.

    Science.gov (United States)

    Safer, Daniel J

    2017-10-01

    The principle evidence that antidepressant medication (ADM) is an effective maintenance treatment for adults with major depressive disorder (MDD) is from placebo substitution trials. These trials enter responders from ADM efficacy trials into randomized, double-blind placebo-controlled (RDBPC) effectiveness trials to measure the rate of MDD relapse over time. However, other randomized maintenance trial methodologies merit consideration and comparison. A systematic review of ADM randomized maintenance trials included research reports from multiple databases. Relapse rate was the main effectiveness outcome assessed. Five ADM randomized maintenance methodologies for MDD responders are described and compared for outcome. These effectiveness trials include: placebo-substitution, ADM/placebo extension, ADM extension, ADM vs. psychotherapy, and treatment as usual. The placebo-substitution trials for those abruptly switched to placebo resulted in unusually high (46%) rates of relapse over 6-12months, twice the continuing ADM rate. These trials were characterized by selective screening, high attrition, an anxious anticipation of a switch to placebo, and a risk of drug withdrawal symptoms. Selectively screened ADM efficacy responders who entered into 4-12month extension trials experienced relapse rates averaging ~10% with a low attrition rate. Non-industry sponsored randomized trials of adults with multiple prior MDD episodes who were treated with ADM maintenance for 1-2years experienced relapse rates averaging 40%. Placebo substitution trial methodology represents only one approach to assess ADM maintenance. Antidepressant maintenance research for adults with MDD should be evaluated for industry sponsorship, attrition, the impact of the switch to placebo, and major relapse differences in MDD subpopulations. Copyright © 2017. Published by Elsevier Inc.

  13. Ganho de peso e comportamento de oviposição de Podisus nigrispinus utilizando lagartas de Spodoptera frugiperda e larvas de Tenebrio molitor como presas

    Directory of Open Access Journals (Sweden)

    Oliveira Harley Nonato de

    2004-01-01

    Full Text Available Esse trabalho avaliou o efeito de diferentes presas e da combinação destas sobre percevejo Podisus nigrispinus. O delineamento experimental foi inteiramente casualizado com três tratamentos e 60 repetições. No tratamento um (T1, os percevejos receberam como alimento, lagartas de Spodoptera frugiperda, de 4o estádio, durante todo o seu ciclo de vida, no tratamento dois (T2, larvas de Tenebrio molitor, também durante o todo ciclo, enquanto que, no tratamento três (T3, foram oferecidas lagartas de S. frugiperda do 2masculine ao 4masculine estádios, e larvas de T. molitor do 4masculine estádio até o final do ciclo de vida. O ganho de peso em todas as fases ninfais e em adultos de até terceiro dia mostrou valores semelhantes de incremento, para todas as dietas utilizadas. No entanto, para os percevejos alimentados, com S. frugiperda (T1, observaram-se uma maior produção de ovos num menor período, com 80% dos ovos até 31masculine dia, enquanto que, no tratamento com larvas de T. molitor (T2, os mesmos 80% foram conseguidos somente no 45masculine dia, e no tratamento com a combinação de presas (T3, no 48masculine dia.

  14. 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.

  15. On the availability of a k-out-of-N system given limited spares and repair capacity under a condition based maintenance strategy

    Energy Technology Data Exchange (ETDEWEB)

    Smidt-Destombes, Karin S. de; Heijden, Matthieu C. van der; Harten, Aart van

    2004-03-01

    This paper considers a k-out-of-N system with identical, repairable components. Maintenance is initiated when the number of failed components exceeds some critical level. After a possible set-up time, all failed components are replaced by spares. A multi-server repair shop repairs the failed components. The system availability depends on the spare part stock level, the maintenance policy and the repair capacity. We present a mathematical model supporting the trade-off between these three parameters. We present both an exact and an approximate approach to analyse our model. In some numerical experiments, we provide insight on the impact of repair capacity, number of spares and preventive maintenance policy on the availability.

  16. Systematic analysis of maintenance strategies of technical systems

    International Nuclear Information System (INIS)

    Laakso, K.; Stroemberg, A.

    2001-01-01

    The paper describes an approach to evaluate and improve the effectiveness of the maintenance strategies of technical systems in operating power plants. In the Experience Based Reliability Centred Maintenance (EBRCM) approach, the analyses of the history of occurred faults and the preventive maintenance program are combined. Changes in the maintenance programs are proposed for reduction of faults or increasing the cost-efficiency of maintenance. The justification of changes is based on simple maintenance indicators and study of the underlying failure and maintenance data. To make the analysis resource-efficient and generate easily the maintenance indicators, suitable data analysis and warehouse tools are used. They facilitate the online access and treatment of the work orders and other planning information in plant information systems. In order to direct the analysis to the important items from maintenance point of view, the equipment of the plant are classified based on their importance for reaching the maintenance objectives such as plant safety, plant availability and worker protection. Maintenance optimisation is directed to those important equipment which exhibit a high number of failures. The other equipment of less maintenance importance, but which exhibit high preventive maintenance costs and low numbers of failures are also analysed to improve the cost-effectiveness of maintenance. After experiences from performing two case studies, both on a standby safety system and a continuously operating process system, Barsebdck Kraft AB adopted the experience based RCM approach as standard method for evaluation of the maintenance action programs and planning of modifications in them. The strength is the applicability and continuity of this method, i.e. each year again. (orig.)

  17. Cost-effectiveness of budesonide/formoterol for maintenance and reliever asthma therapy in Denmark--cost-effectiveness analysis based on five randomised controlled trials

    DEFF Research Database (Denmark)

    Wickstrøm, Jannie; Dam, Nanna; Malmberg, Irena

    2009-01-01

    . The aim of this study was to determine the cost-effectiveness of the Symbicort SMART regime in Denmark vs higher dose inhaled corticosteroid (ICS) plus reliever medication, similar dose inhaled corticosteroid/long-acting beta(2)-agonist (ICS/LABA) combination therapy plus reliever medication or higher......Budesonide/formoterol maintenance and reliever therapy (Symbicort SMART) is an effective asthma-management regime where patients use budesonide/formoterol both as maintenance treatment and as additional doses as needed to improve overall asthma control by reducing symptoms and exacerbations...

  18. Building Maintenance, Management, and Budgeting.

    Science.gov (United States)

    Pawsey, M. R.

    1982-01-01

    Australian methods and formulas for funding building maintenance and management are outlined and found to be haphazard. Discussed are: ultimate costs of deferred maintenance, major plant replacements, life cycle costing, types of maintenance programs (including full preventive maintenance), use of computer programs for planning, and organization…

  19. Assessment of Surface Ship Maintenance Requirements

    Science.gov (United States)

    2015-01-01

    may not be reflected in average class maintenance cost. If this is the case, the deferred actions may in fact pile up significantly and result in even...and preservation of the propulsion- combustion air intakes and louvers. Mandatory maintenance requirements are for the inspection of intakes annually...Pitch Propeller every dry docking. • SWLIN 2513X: Condition-based repair and preservation of the propulsion- combustion air intakes and louvers. Mandatory

  20. Modelling inspection policies for building maintenance.

    Science.gov (United States)

    Christer, A H

    1982-08-01

    A method of assessing the potential of an inspection maintenance policy as opposed to an existing breakdown maintenance policy for a building complex is developed. The method is based upon information likely to be available and specific subjective assessments which could be made available. Estimates of the expected number of defects identified at an inspection and the consequential cost saving are presented as functions of the inspection frequency.

  1. Using the system maintenance datastore to characterize lifetime maintenance for PLiM

    International Nuclear Information System (INIS)

    Watson, P.; Dam, R.; Nickerson, J.

    2004-01-01

    A comprehensive Plant Life Management (PLiM) program involves evaluating a large amount of information. For any plant, there are numerous maintenance, surveillance and inspection programs for the important systems, structures and components. There is extensive industry experience on component failure modes, degradation mechanisms and recommended maintenance practices. This information forms the basis of the aging assessment work, through which improvements to these plant programs are identified. AECL has developed several tools to manage the quantities of information required in aging assessment studies, such as the SYSTMS (SYtematic approach for the development of STrategy for Maintenance and Surveillance) tool and the System Maintenance Datastore (SMD). The SMD has been developed to serve as a hub to a Systematic based Adaptive Maintenance Program (SAMP), by storing maintenance resource requirements for recommended maintenance tasks for use by the other processes in a SAMP. The SMD can be used to (a) quantify the savings or cost of optimising a maintenance program, (b) characterize and understand long term trends in condition-based maintenance due to component aging, (c) quantify the resource savings due to optimum timing of component replacement or general plant refurbishment, and (d) provide aging assessment cost information for input to plant asset evaluation. The SMD contains data for regular maintenance program tasks, plant condition assessment recommendations, and equipment refurbishment costs. A prototype SMD has been developed with data tables populated with information from operating CANDU stations. The SMD is now available to be used either with a SYSTMS evaluation or with a plant's database of maintenance tasks. (author)

  2. Building an experience factory for maintenance

    Science.gov (United States)

    Valett, Jon D.; Condon, Steven E.; Briand, Lionel; Kim, Yong-Mi; Basili, Victor R.

    1994-01-01

    This paper reports the preliminary results of a study of the software maintenance process in the Flight Dynamics Division (FDD) of the National Aeronautics and Space Administration/Goddard Space Flight Center (NASA/GSFC). This study is being conducted by the Software Engineering Laboratory (SEL), a research organization sponsored by the Software Engineering Branch of the FDD, which investigates the effectiveness of software engineering technologies when applied to the development of applications software. This software maintenance study began in October 1993 and is being conducted using the Quality Improvement Paradigm (QIP), a process improvement strategy based on three iterative steps: understanding, assessing, and packaging. The preliminary results represent the outcome of the understanding phase, during which SEL researchers characterized the maintenance environment, product, and process. Findings indicate that a combination of quantitative and qualitative analysis is effective for studying the software maintenance process, that additional measures should be collected for maintenance (as opposed to new development), and that characteristics such as effort, error rate, and productivity are best considered on a 'release' basis rather than on a project basis. The research thus far has documented some basic differences between new development and software maintenance. It lays the foundation for further application of the QIP to investigate means of improving the maintenance process and product in the FDD.

  3. The MERC maintenance system

    International Nuclear Information System (INIS)

    Izquierdo, J.J.; Chauvire, P.; Plessis, L.

    1991-01-01

    Maintenance in the modern commercial reprocessing plants is a subject of the highest priority in order to guarantee availability for the whole life of the plant. The design concept of the UP3 reprocessing plant at La Hague identified several categories of equipment according to their maintenance design principles. Among them, Standard Process Equipment such as pumps, valves, ejectors and filters which need periodic maintenance. These equipment items are designed in removable modular form to avoid the need to disconnect piping. Removal is performed under shielding and without breach of containment through the use of a transfer cask that is connected to the cell containing the equipment to be removed. This transfer cask is called MERC (Mobile Equipment Replacement Cask). Containment is preserved by an air-tight system consisting of coupled doors, with a special connecting gasket. This system can remove and replace failed equipment, without spreading contamination to work areas. (author)

  4. Maintenance of nuclear medicine instruments

    International Nuclear Information System (INIS)

    Ambro, P.

    1992-01-01

    Maintenance of instruments is generally of two kinds: (a) corrective maintenance, on a non-scheduled basis, to restore equipment to a functional status by repairs; (b) preventive maintenance, to keep equipment in a specified functional condition by providing systematic inspection, quality control, detection and correction of early malfunctions. Most of the instruments used in nuclear medicine are rather complex systems built from mechanical, electrical and electronic parts. Any one of these components is liable to fail at some time or other. Repair could be done only by a specialist who is able to evaluate the condition of the various parts ranging from cables to connectors, from scintillators to photomultipliers, from microprocessors to microswitches. The knowledge of the intricacies of the various electronic components required for their repairs is quite wide and varied. The electronics industry turns out more and more multi-purpose chips which can carry out the functions of many parts used in the instruments of the earlier generation. This provides protection against unauthorized copying of the circuits but it serves another purpose as well of inhibiting repairs by non-factory personnel. These trends of the instrument design should be taken into consideration when a policy has to be developed for the repairs of the hospital based equipment

  5. Concurrent use of data base and graphics computer workstations to provide graphic access to large, complex data bases for robotics control of nuclear surveillance and maintenance

    International Nuclear Information System (INIS)

    Dalton, G.R.; Tulenko, J.S.; Zhou, X.

    1990-01-01

    The University of Florida is part of a multiuniversity research effort, sponsored by the US Department of Energy which is under way to develop and deploy an advanced semi-autonomous robotic system for use in nuclear power stations. This paper reports on the development of the computer tools necessary to gain convenient graphic access to the intelligence implicit in a large complex data base such as that in a nuclear reactor plant. This program is integrated as a man/machine interface within the larger context of the total computerized robotic planning and control system. The portion of the project described here addresses the connection between the three-dimensional displays on an interactive graphic workstation and a data-base computer running a large data-base server program. Programming the two computers to work together to accept graphic queries and return answers on the graphic workstation is a key part of the interactive capability developed

  6. Composição do ganho e exigências de energia e proteína para ganho de peso em bovinos Nelore puros e mestiços Gain composition and net energy and protein requirements for weight gain in Nellore and crossbred cattle

    Directory of Open Access Journals (Sweden)

    José Antônio de Freitas

    2006-06-01

    Full Text Available Objetivou-se estimar a composição do ganho e as exigências de energia e proteína para ganho de peso em bovinos Nelore puros e mestiços. Utilizaram-se 60 bovinos machos (Nelore, F1 Nelore x Angus, F1 Nelore x Pardo-Suíço e F1 Nelore x Simental não-castrados, com 10 a 11 meses de idade e peso médio inicial de 286, 309, 333 e 310 kg, respectivamente. O delineamento utilizado foi o inteiramente casualizado, com quatro grupos genéticos, submetidos a quatro níveis de concentrado na ração (30, 40, 60 e 70%. Três animais de cada grupo genético foram abatidos ao início do experimento e serviram como referência na determinação da composição corporal inicial. As exigências líquidas de proteína e energia para ganho de 1 kg de peso corporal vazio (PCV foram estimadas pela equação Y' = a. b. X (b-1, em que a e b são os coeficientes das equações de regressão dos conteúdos de energia e proteína e X, o PCV dos animais. O teste de identidade de modelos não-lineares indicou não haver diferenças entre grupos genéticos para as exigências de energia e proteína para ganho de peso. Verificou-se decréscimo de 10,6% nas exigências de proteína e elevação de 37,8% nas exigências de energia para ganho de peso entre 250 e 550 kg, o que está relacionado à elevação do teor de gordura e à redução no teor de proteína com o acréscimo no PCV. As exigências líquidas de proteína e energia para ganho de peso foram estimadas em 143,5 g e 4,7 Mcal para o peso vivo de 450 kg.The objectives of this trial were to estimate gain composition and energy and protein requirements for weight gain of purebred and crossbred Nellore. Sixty young bulls averaging 10 to 11 months of age from four genetic groups: Nellore, F1 Nellore x Angus, F1 Nellore x Brown Swiss and F1 Nellore x Simental and initial average body weights of 286, 309, 333 and 310 kg, respectively, were used in this study. A completely randomized design was adopted and bulls from

  7. Maintenance simulation: Software issues

    Energy Technology Data Exchange (ETDEWEB)

    Luk, C.H.; Jette, M.A.

    1995-07-01

    The maintenance of a distributed software system in a production environment involves: (1) maintaining software integrity, (2) maintaining and database integrity, (3) adding new features, and (4) adding new systems. These issues will be discussed in general: what they are and how they are handled. This paper will present our experience with a distributed resource management system that accounts for resources consumed, in real-time, on a network of heterogenous computers. The simulated environments to maintain this system will be presented relate to the four maintenance areas.

  8. Training of maintenance personnel

    International Nuclear Information System (INIS)

    Rabouhams, J.

    1986-01-01

    This lecture precises the method and means developed by EDF to ensure the training of maintenance personnel according to their initial educational background and their experience. The following points are treated: General organization of the training for maintenance personnel in PWR and GCR nuclear power stations and in Creys Malville fast breeder reactor; Basic nuclear training and pedagogical aids developed for this purpose; Specific training and training provided by contractors; complementary training taking into account the operation experience and feedback; Improvement of velocity, competence and safety during shut-down operations by adapted training. (orig.)

  9. Ovariectomy effect in heifers Nelore x Angus, Bos taurus indicus x Bos taurus taurus on the weight gains /Efeito da ovariectomia em novilhas Nelore x Angus, Bos taurus indicus x Bos taurus taurus sobre os ganhos de peso

    Directory of Open Access Journals (Sweden)

    Sérgio do Nascimento Kronka

    2007-10-01

    Full Text Available This study aimed to evaluate the weight gain in cross breed heifers Nelore X Angus, spayed and nonspayed, kept on pasture and confinement. The animals were allotted in two groups as follows: group 1 consisted of 30 nonspayed heifers with 18 months old. Group 2 was composed of 30 spayed heifers with 18 months old. The animals were allotted in pasture of Brachiaria decumbens and weighted at 39and 75 days. Significant difference was observed between the average daily gain of the two groups – G1 and G2 (75th day, respectively (0.51 kg and 0.65 kg; PEsse estudo teve o objetivo de avaliar o ganho de peso em novilhas mestiças Nelore x Angus, castradas e não castradas, mantidas em pastagem e confinamento. Os animais foram alocados em dois grupos assim constituídos: grupo 1 formado por 30 novilhas não castradas com 18 meses de idade. Grupo 2 composto por 30 novilhas castradas com 18 meses de idade. Os animais foram mantidos em pastagem de Brachiaria decumbens e pesados aos 39 e 75 dias. Diferença significativa foi observada entre o ganho médio diário dos dois grupos – G1 e G2 (75ºdia, respectivamente (0,51 kg e 0,65 kg; P < 0,01. No dia seguinte (76ºdia, todos os animais foram transferidos e mantidos por 144 dias no confinamento. Diferença significativa foi observada entre o ganho médio diário dos dois grupos – G1 e G2 (144ºdia, respectivamente (0,73 kg e 0,58 kg; P < 0,01. Os resultados desse experimento mostraram que novilhas castradas apresentaram um maior ganho diário em pastagem.

  10. On the availability of a k-out-of-N system given limited spares and repair capacity under a condition based maintenance strategy

    NARCIS (Netherlands)

    de Smidt-Destombes, K.S.; van der Heijden, M.C.; van Harten, A.

    2004-01-01

    This paper considers a k-out-of-N system with identical, repairable components. Maintenance is initiated when the number of failed components exceeds some critical level. After a possible set-up time, all failed components are replaced by spares. A multi-server repair shop repairs the failed

  11. The Impact of Oral Hygiene Maintenance on the Association Between Periodontitis and Osteoporosis: A Nationwide Population-Based Cross Sectional Study.

    Science.gov (United States)

    Huang, Yi-Fang; Chang, Chung-Ta; Liu, Shih-Ping; Muo, Chih-Hsin; Tsai, Chun-Hao; Hong, Hsiang-Hsi; Shen, Yu-Fu; Wu, Ching-Zong

    2016-02-01

    Both periodontitis and osteoporosis have similar sign of bone resorption in nature. However, the relationship of the severity between these 2 bone-loss diseases is still uncertain.The aim of this study was to investigate the association between the severity of osteoporosis and periodontitis regarding the impact of oral hygiene maintenance. In total, 35,127 osteoporosis patients and 50,498 comparisons were derived from the Longitudinal Health Insurance Database of Taiwan between 2000 and 2010. The population was subdivided into groups according to the different level oral hygiene maintenance and the severity of periodontitis and osteoporosis. The association between osteoporosis and periodontitis was estimated by multinomial logistic regression and rank correlation by Kendall rank correlation test, presented by odds ratio (OR), and 5% confidence intervals (CIs).After controlling the age, sex, and comorbidities, variables in the good oral hygiene maintenance population, we found that periodontitis raised 1.29-fold risk of osteoporosis (95% CI = 1.12-1.49); the risk of osteoporosis was increased with the elevated severity of periodontitis from 1.27 (95% CI = 1.08-1.48) to 1.38 (95% CI = 1.01-1.89). There is a positive correlation between the severity of periodontitis and osteoporosis occurrence in this population (OR = 1.27-1.46; Kendall rank correlation test P = 0.0003). In the poor oral hygiene maintenance population, periodontitis patients had 6.02-fold risk of osteoporosis than those who without periodontitis (95% CI = 4.65-7.81); the risk of osteoporosis was increased with periodontitis severity from 5.96 (95% CI = 4.48-7.92) to 6.37 (95% CI = 3.36-12.1).This result indicated the periodontitis and osteoporosis are conjunctive. The sudden periodontal breakdown of those who with good oral hygiene maintenance might be an indicator for the risk of osteoporosis; if those who were diagnosed as osteoporosis must pay more attention to their

  12. Conteúdo corporal e exigências líquidas e dietéticas de macroelementos minerais (Ca, P, Mg, Na e K de novilhos mestiços Holandês-Gir em ganho compensatório Body content and net and dietary requirements of macrominerals (Ca, P, Mg, Na and K of crossbred Holstein-Gyr steers during compensatory growth

    Directory of Open Access Journals (Sweden)

    Maria Izabel Vieira de Almeida

    2001-06-01

    Full Text Available Foram utilizados 39 novilhos mestiços Holandês-Gir, com o objetivo de avaliar a influência do ganho compensatório sobre o conteúdo corporal e as exigências líquidas e dietéticas de cálcio, fósforo, magnésio, sódio e potássio de bovinos. Trinta animais foram submetidos à alta pressão de pastejo, enquanto nove tiveram oferta ilimitada de pasto (grupo ganho contínuo, durante 114 dias, após o qual seis animais do primeiro grupo e três do segundo grupo foram abatidos e os restantes, confinados. Entre os animais do primeiro grupo, 12 receberam alimentação ad libitum (grupo ganho compensatório e 12 receberam alimento 15% acima da mantença (grupo mantença, enquanto os seis animais do grupo ganho contínuo receberam a mesma dieta ad libitum. Foram ajustadas equações de regressão do logaritmo do conteúdo corporal dos minerais, em função do logaritmo do peso corporal vazio (PCVZ. As exigências de minerais não diferiram quanto ao tratamento, e as exigências líquidas para ganho de 1 kg PCVZ variaram de 10,04 a 12,38 g para cálcio, 9,33 a 9,41 g para fósforo, 0,50 a 0,38 g para magnésio, 1,22 a 1,07 g para sódio e 2,24 a 2,75 g para potássio, para novilhos com pesos entre 150 e 450 kg, respectivamente. As exigências dietéticas, para ganho de 1 kg de peso vivo, variaram de 15,88 a 25,68 g para cálcio, 16,62 a 10,35 g para fósforo, 5,12 a 9,82 g para magnésio, 2,25 a 4,35 g para sódio e 18,23 a 49,18 g para potássio.Thirty-nine crossbreed Holstein-Gyr steers were used aiming to evaluate the influence of compensatory growth on body content and on net and dietary requirements of calcium, phosphorus, magnesium, sodium, and potassium of bovines. Thirty animals were submitted to a high pasture stocking rate, while nine had free access to the pasture (continuous growth group, during 114 days. After that, six animals from the first group and three from the second group were slaughtered, and the remaining animals were

  13. Condition based maintenance of a 20 kV-PE/XLPE-insulated cable network using the IRC-Analysis; Zustandsorientierte Instandhaltung eines polymerisolierten 20-kV-Kabelnetzes mit der IRC-Analyse. Moderne Diagnostik reduziert Stoerungsrate

    Energy Technology Data Exchange (ETDEWEB)

    Hoff, G.; Kranz, H.G. [BUGH Wuppertal (Germany). Labs. fuer Hochspannungstechnik; Beigert, M.; Petzold, F. [Seba Dynatronic Mess- und Ortungstechnik GmbH, Baunach (Germany); Kneissl, C. [Bereich Konzeption und Messtechnik, Lech Elektrizitaetswerke AG, Augsburg (Germany)

    2001-10-22

    For a preventive maintenance of a polymer insulated cable network a destruction free estimation of the status of the buried PE/XLPE-cables is needed. This contribution presents a condition based maintenance concept which is based on the IRC-Analysis. With this concept a major German utility was able to reduce the amount of failures in a part of the 20kV-cable network. The general tendency of increasing faults was broken. (orig.) [German] Die praeventive Instandhaltung in polymerisolierten Kabelnetzen setzt eine zerstoerungsfreie Zustandbestimmung von gelegten PE/VPE-isolierten Kabeln voraus. Die-Verfasser beschreiben ein zustandsorientiertes Wartungskonzept auf Basis der IRC-Analyse, mit dem es gelungen ist, in einem Teil des 20-kV-Kabelnetzes eines Energieversorgers die in der Vergangenheit stetig steigende Stoerungsrate drastisch zu reduzieren. (orig.)

  14. 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

  15. Evaluation System and Implementation Countermeasure of Automobile Green Maintenance

    Science.gov (United States)

    Zhang, Fei; Xie, Xinxin; Yan, Chaoyong

    2018-01-01

    Green maintenance research is in the beginning of our country, the work is being explored. Based on the existing research results at home and abroad, this paper learns and draws lessons from the experiences and lessons of foreign advanced countries and domestic advanced enterprises. In the face of the challenges brought by economic development and energy saving and emission reduction, this paper discusses the green maintenance theory and security system, And the research status of green maintenance content and system at home and abroad, through the deletion and selection of green maintenance index, through the AHP method to determine the green evaluation criteria, and the introduction of C equivalent evaluation system, the use of fuzzy synthesis Evaluation method to build a green maintenance evaluation model, and the actual validation, put forward the implementation of green maintenance feasibility programs and related security recommendations, vehicle maintenance enterprises to carry out green maintenance, improve business efficiency and reduce environmental management costs to provide theoretical basis. And to achieve effective reduction of environmental pollution, reduce maintenance costs of the target, a reasonable promotion of maintenance and environmental protection and sustainable development. Promote green maintenance from research to practice, from the laboratory to the maintenance of enterprises, from the pilot to the overall development and transformation.

  16. Diesel Vehicle Maintenance Competencies.

    Science.gov (United States)

    Braswell, Robert; And Others

    Designed to provide a model set of competencies, this manual presents tasks which were identified by employers, employees, and teachers as important in a postsecondary diesel vehicle maintenance curriculum. The tasks are divided into seven major component areas of instruction: chassis and suspension, diesel engines, diesel fuel, electrical,…

  17. Maintenance and environmental qualification

    International Nuclear Information System (INIS)

    Martin, R.S.; Austin, D.G.

    1995-01-01

    The design of today's nuclear generating plants involves many detailed design considerations. This includes comprehensive look at aging effects on plant components over their expected lifetimes. This is important to ensuring that the plant operates safely throughout its life. The effects of aging are required to be documented in detail in today's designs. This documentation provides assurance that safe operating conditions are maintained throughout the station life cycle. This requirement is analogous to the longer standing requirement to ensure pressure boundary integrity. The pressure boundary integrity requirement has existed in the industry since its inception. The subject of plant aging effects and the maintenance of functionality is known as Environmental Qualification (EQ). This paper will attempt to explain the wisdom of EQ and the potential for optimizing maintenance activities (to move from reactive to proactive activities), within the context of the overall maintenance program. It is the author's intent to encourage the active involvement of maintenance professionals in the effective implementation of the ongoing EQ program so that the benefits are maximized

  18. CH Packaging Maintenance Manual

    International Nuclear Information System (INIS)

    Washington TRU Solutions

    2002-01-01

    This procedure provides instructions for performing inner containment vessel (ICV) and outer containment vessel (OCV) maintenance and periodic leakage rate testing on the following packaging seals and corresponding seal surfaces using a nondestructive helium (He) leak test. In addition, this procedure provides instructions for performing ICV and OCV structural pressure tests

  19. Maintenance: problem and solution

    CERN Multimedia

    CERN Bulletin

    2012-01-01

    Equipment that is often unique, machines that are as old as the Laboratory, continuous and demanding performance requirements: these are the challenges faced by CERN’s accelerator maintenance teams. There are some twenty such teams, attached to different departments. A new project aims to standardise their procedures to make their work easier, and you can be a part of it.   “For the past year or so, the Accelerator and Technologies Sector and the GS Department have been working together on identifying the needs of the different teams that perform maintenance on CERN’s equipment. We are now ready to provide computer support with detailed specifics about the processes that need to be set up,” explains Goran Perinić, one of the leaders in CERN’s new Maintenance Management project (MMP). Since the LHC entered operation, the responsibilities of the technical teams have been broadened to cover maintenance of the collider and that of its injectors...

  20. Building Maintenance Syllabus.

    Science.gov (United States)

    Fischer, Joseph; Messier, Joseph

    Building maintenance is a basic two-year trade education course requiring 2 1/2 hours of study on each of 160 teaching days per year. Student abilities should range from those capable of the simplest custodial work to those who may eventually be superintendents of building complexes. The syllabus is organized in sections by traditional skills…