Coordination between Generation and Transmission Maintenance Scheduling by Means of Multi-agent Technique

Science.gov (United States)

Nagata, Takeshi; Tao, Yasuhiro; Utatani, Masahiro; Sasaki, Hiroshi; Fujita, Hideki

This paper proposes a multi-agent approach to maintenance scheduling in restructured power systems. The restructuring of electric power industry has resulted in market-based approaches for unbundling a multitude of service provided by self-interested entities such as power generating companies (GENCOs), transmission providers (TRANSCOs) and distribution companies (DISCOs). The Independent System Operator (ISO) is responsible for the security of the system operation. The schedule submitted to ISO by GENCOs and TRANSCOs should satisfy security and reliability constraints. The proposed method consists of several GENCO Agents (GAGs), TARNSCO Agents (TAGs) and a ISO Agent(IAG). The IAG’s role in maintenance scheduling is limited to ensuring that the submitted schedules do not cause transmission congestion or endanger the system reliability. From the simulation results, it can be seen the proposed multi-agent approach could coordinate between generation and transmission maintenance schedules.

Preventive maintenance scheduling by variable dimension evolutionary algorithms

International Nuclear Information System (INIS)

Limbourg, Philipp; Kochs, Hans-Dieter

2006-01-01

Black box optimization strategies have been proven to be useful tools for solving complex maintenance optimization problems. There has been a considerable amount of research on the right choice of optimization strategies for finding optimal preventive maintenance schedules. Much less attention is turned to the representation of the schedule to the algorithm. Either the search space is represented as a binary string leading to highly complex combinatorial problem or maintenance operations are defined by regular intervals which may restrict the search space to suboptimal solutions. An adequate representation however is vitally important for result quality. This work presents several nonstandard input representations and compares them to the standard binary representation. An evolutionary algorithm with extensions to handle variable length genomes is used for the comparison. The results demonstrate that two new representations perform better than the binary representation scheme. A second analysis shows that the performance may be even more increased using modified genetic operators. Thus, the choice of alternative representations leads to better results in the same amount of time and without any loss of accuracy

Monitoring Strategies in Permeable Pavement Systems to Optimize Maintenance Scheduling

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As the surface in a permeable pavement system clogs and performance decreases, maintenance is required to preserve the design function. Currently, guidance is limited for scheduling maintenance on an as needed basis. Previous research has shown that surface clogging in a permea...

Comparison of genetic algorithm and harmony search for generator maintenance scheduling

International Nuclear Information System (INIS)

Khan, L.; Mumtaz, S.; Khattak, A.

2012-01-01

GMS (Generator Maintenance Scheduling) ranks very high in decision making of power generation management. Generators maintenance schedule decides the time period of maintenance tasks and a reliable reserve margin is also maintained during this time period. In this paper, a comparison of GA (Genetic Algorithm) and US (Harmony Search) algorithm is presented to solve generators maintenance scheduling problem for WAPDA (Water And Power Development Authority) Pakistan. GA is a search procedure, which is used in search problems to compute exact and optimized solution. GA is considered as global search heuristic technique. HS algorithm is quite efficient, because the convergence rate of this algorithm is very fast. HS algorithm is based on the concept of music improvisation process of searching for a perfect state of harmony. The two algorithms generate feasible and optimal solutions and overcome the limitations of the conventional methods including extensive computational effort, which increases exponentially as the size of the problem increases. The proposed methods are tested, validated and compared on the WAPDA electric system. (author)

Measuring robustness of port plug maintenance schedules in fusion remote handling

Energy Technology Data Exchange (ETDEWEB)

Schoen, P.W., E-mail: p.w.schoen@heemskerk-innovative.nl [Heemskerk Innovative Technology, Sassenheim (Netherlands); Thomas, J. [CCFE EURATOM/CCFE Fusion Association, Culham Science Centre, Abingdon OX14 3DB (United Kingdom); Boessenkool, H. [FOM Institute DIFFER, Association EURATOM-FOM, Partner in the Trilateral Euregio Cluster, PO Box 1207, 3430 BE Nieuwegein (Netherlands); Heemskerk, C.J.M. [Heemskerk Innovative Technology, Sassenheim (Netherlands)

2015-12-15

Unexpected events during maintenance operations of a fusion plant like JET or ITER may require rescheduling, suspending the execution of the current procedure to pick it up later. In this paper, we look at how the introduction of slack influences the port plug maintenance schedule robustness. We introduce a metrics to measure the robustness. Simulating disruptions we evaluate the effect on a schedule. Finally, we show how the robustness is affected when introducing different amounts of slack.

Measuring robustness of port plug maintenance schedules in fusion remote handling

International Nuclear Information System (INIS)

Schoen, P.W.; Thomas, J.; Boessenkool, H.; Heemskerk, C.J.M.

2015-01-01

Unexpected events during maintenance operations of a fusion plant like JET or ITER may require rescheduling, suspending the execution of the current procedure to pick it up later. In this paper, we look at how the introduction of slack influences the port plug maintenance schedule robustness. We introduce a metrics to measure the robustness. Simulating disruptions we evaluate the effect on a schedule. Finally, we show how the robustness is affected when introducing different amounts of slack.

An optimal dynamic interval preventive maintenance scheduling for series systems

International Nuclear Information System (INIS)

Gao, Yicong; Feng, Yixiong; Zhang, Zixian; Tan, Jianrong

2015-01-01

This paper studies preventive maintenance (PM) with dynamic interval for a multi-component system. Instead of equal interval, the time of PM period in the proposed dynamic interval model is not a fixed constant, which varies from interval-down to interval-up. It is helpful to reduce the outage loss on frequent repair parts and avoid lack of maintenance of the equipment by controlling the equipment maintenance frequency, when compared to a periodic PM scheme. According to the definition of dynamic interval, the reliability of system is analyzed from the failure mechanisms of its components and the different effects of non-periodic PM actions on the reliability of the components. Following the proposed model of reliability, a novel framework for solving the non-periodical PM schedule with dynamic interval based on the multi-objective genetic algorithm is proposed. The framework denotes the strategies include updating strategy, deleting strategy, inserting strategy and moving strategy, which is set to correct the invalid population individuals of the algorithm. The values of the dynamic interval and the selections of PM action for the components on every PM stage are determined by achieving a certain level of system availability with the minimum total PM-related cost. Finally, a typical rotary table system of NC machine tool is used as an example to describe the proposed method. - Highlights: • A non-periodic preventive maintenance scheduling model is proposed. • A framework for solving the non-periodical PM schedule problem is developed. • The interval of non-periodic PM is flexible and schedule can be better adjusted. • Dynamic interval leads to more efficient solutions than fixed interval does

A PSO approach for preventive maintenance scheduling optimization

International Nuclear Information System (INIS)

Pereira, C.M.N.A.; Lapa, C.M.F.; Mol, A.C.A.; Luz, A.F. da

2009-01-01

This work presents a Particle Swarm Optimization (PSO) approach for preventive maintenance policy optimization, focused in reliability and cost. The probabilistic model for reliability and cost evaluation is developed in such a way that flexible intervals between maintenance are allowed. As PSO is skilled for realcoded continuous spaces, a non-conventional codification has been developed in order to allow PSO to solve scheduling problems (which is discrete) with variable number of maintenance interventions. In order to evaluate the proposed methodology, the High Pressure Injection System (HPIS) of a typical 4-loop PWR has been considered. Results demonstrate ability in finding optimal solutions, for which expert knowledge had to be automatically discovered by PSO. (author)

Monitoring Strategies in Permeable Pavement Systems to Optimize Maintenance Scheduling - abstract

Science.gov (United States)

As the surface in a permeable pavement system clogs and performance decreases, maintenance is required to preserve the design function. Currently, guidance is limited for scheduling maintenance on an as needed basis. Previous research has shown that surface clogging in a permea...

Single machine scheduling with time-dependent linear deterioration and rate-modifying maintenance

OpenAIRE

Rustogi, Kabir; Strusevich, Vitaly A.

2015-01-01

We study single machine scheduling problems with linear time-dependent deterioration effects and maintenance activities. Maintenance periods (MPs) are included into the schedule, so that the machine, that gets worse during the processing, can be restored to a better state. We deal with a job-independent version of the deterioration effects, that is, all jobs share a common deterioration rate. However, we introduce a novel extension to such models and allow the deterioration rates to change af...

Multi-objective group scheduling optimization integrated with preventive maintenance

Science.gov (United States)

Liao, Wenzhu; Zhang, Xiufang; Jiang, Min

2017-11-01

This article proposes a single-machine-based integration model to meet the requirements of production scheduling and preventive maintenance in group production. To describe the production for identical/similar and different jobs, this integrated model considers the learning and forgetting effects. Based on machine degradation, the deterioration effect is also considered. Moreover, perfect maintenance and minimal repair are adopted in this integrated model. The multi-objective of minimizing total completion time and maintenance cost is taken to meet the dual requirements of delivery date and cost. Finally, a genetic algorithm is developed to solve this optimization model, and the computation results demonstrate that this integrated model is effective and reliable.

Scheduling a maintenance activity under skills constraints to minimize total weighted tardiness and late tasks

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Djalal Hedjazi

2015-04-01

Full Text Available Skill management is a key factor in improving effectiveness of industrial companies, notably their maintenance services. The problem considered in this paper concerns scheduling of maintenance tasks under resource (maintenance teams constraints. This problem is generally known as unrelated parallel machine scheduling. We consider the problem with a both objectives of minimizing total weighted tardiness (TWT and number of tardiness tasks. Our interest is focused particularly on solving this problem under skill constraints, which each resource has a skill level. So, we propose a new efficient heuristic to obtain an approximate solution for this NP-hard problem and demonstrate his effectiveness through computational experiments. This heuristic is designed for implementation in a static maintenance scheduling problem (with unequal release dates, processing times and resource skills, while minimizing objective functions aforementioned.

Stochastic short-term maintenance scheduling of GENCOs in an oligopolistic electricity market

International Nuclear Information System (INIS)

Fotouhi Ghazvini, Mohammad Ali; Canizes, Bruno; Vale, Zita; Morais, Hugo

2013-01-01

Highlights: ► Decision making under uncertainty. ► Stochastic Mixed Integer Quadratic Programming applied to short-term maintenance scheduling. ► Outage scheduling in Oligopolistic electricity markets. ► Generation companies maintenance scheduling. -- Abstract: In the proposed model, the independent system operator (ISO) provides the opportunity for maintenance outage rescheduling of generating units before each short-term (ST) time interval. Long-term (LT) scheduling for 1 or 2 years in advance is essential for the ISO and the generation companies (GENCOs) to decide their LT strategies; however, it is not possible to be exactly followed and requires slight adjustments. The Cournot-Nash equilibrium is used to characterize the decision-making procedure of an individual GENCO for ST intervals considering the effective coordination with LT plans. Random inputs, such as parameters of the demand function of loads, hourly demand during the following ST time interval and the expected generation pattern of the rivals, are included as scenarios in the stochastic mixed integer program defined to model the payoff-maximizing objective of a GENCO. Scenario reduction algorithms are used to deal with the computational burden. Two reliability test systems were chosen to illustrate the effectiveness of the proposed model for the ST decision-making process for future planned outages from the point of view of a GENCO.

Nuclear Power Plant Preventive Maintenance Scheduling Problem with Fuzziness

International Nuclear Information System (INIS)

Abass, S.A.; Abdallah, A.S.

2013-01-01

Maintenance activity is regarded as the most important key factor for the safety, reliability and economy of a nuclear power plant. Preventive maintenance refers to set of planned activities which include nondestructive testing and periodic inspection as well as maintenance. In this paper, we address the problem of nuclear power plant preventive maintenance scheduling with uncertainty. The uncertainty will be represented by fuzzy parameters. The problem is how to determine the period for which generating units of an electric system should be taken off line for planned preventive maintenance over specific time horizon. Preventive maintenance activity of a nuclear power plant is an important issue as it designed to extend the plant life . It is more required to review the maintenance not only from the view point of safety and reliability but also economy. Preventive maintenance program exists to ensure that nuclear safety significant equipment will function when it is supposed to. Also this problem is extremely important because a failure in a power plant may cause a general breakdown in an electric network. In this paper a mixed integer programming model is used to express this problem. In proposed model power demand is taken as fuzzy parameters. A case study is provided to demonstrate the efficiency of the proposed model.

Performance deterioration modeling and optimal preventive maintenance strategy under scheduled servicing subject to mission time

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Li Dawei

2014-08-01

Full Text Available Servicing is applied periodically in practice with the aim of restoring the system state and prolonging the lifetime. It is generally seen as an imperfect maintenance action which has a chief influence on the maintenance strategy. In order to model the maintenance effect of servicing, this study analyzes the deterioration characteristics of system under scheduled servicing. And then the deterioration model is established from the failure mechanism by compound Poisson process. On the basis of the system damage value and failure mechanism, the failure rate refresh factor is proposed to describe the maintenance effect of servicing. A maintenance strategy is developed which combines the benefits of scheduled servicing and preventive maintenance. Then the optimization model is given to determine the optimal servicing period and preventive maintenance time, with an objective to minimize the system expected life-cycle cost per unit time and a constraint on system survival probability for the duration of mission time. Subject to mission time, it can control the ability of accomplishing the mission at any time so as to ensure the high dependability. An example of water pump rotor relating to scheduled servicing is introduced to illustrate the failure rate refresh factor and the proposed maintenance strategy. Compared with traditional methods, the numerical results show that the failure rate refresh factor can describe the maintenance effect of servicing more intuitively and objectively. It also demonstrates that this maintenance strategy can prolong the lifetime, reduce the total lifetime maintenance cost and guarantee the dependability of system.

Reusable rocket engine preventive maintenance scheduling using genetic algorithm

International Nuclear Information System (INIS)

Chen, Tao; Li, Jiawen; Jin, Ping; Cai, Guobiao

2013-01-01

This paper deals with the preventive maintenance (PM) scheduling problem of reusable rocket engine (RRE), which is different from the ordinary repairable systems, by genetic algorithm. Three types of PM activities for RRE are considered and modeled by introducing the concept of effective age. The impacts of PM on all subsystems' aging processes are evaluated based on improvement factor model. Then the reliability of engine is formulated by considering the accumulated time effect. After that, optimization model subjected to reliability constraint is developed for RRE PM scheduling at fixed interval. The optimal PM combination is obtained by minimizing the total cost in the whole life cycle for a supposed engine. Numerical investigations indicate that the subsystem's intrinsic reliability characteristic and the improvement factor of maintain operations are the most important parameters in RRE's PM scheduling management

PROCESS OF CHANGES OF MAINTENANCE-FREE ONBOARD SYSTEM OPERATIONAL STATUS BETWEEN SCHEDULED MAINTENANCES

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Andrey Mikhaylovich Bronnikov

2017-01-01

Full Text Available In this article the authors consider the problem of simulating the process of a maintenance-free between scheduled maintenance aircraft system operational status changes, which failure during the flight leads to the disaster. On-board equipment with automatic self-repair between routine maintenance in the event the components fail is called maintenance-free. During operation, onboard equipment accumulates failures maintaining its functions with a safety level not lower than the required minimum. Trouble shooting is carried out either at the end of between-maintenance period (as a rule, or after the failure, which led to the functions disorder or to the decrease below the target level of flight safety (as an exception. The system contains both redundant and nonredundant units and elements with the known failure rates. The system can be in one of the three states: operable, extreme, failed. The excessive redundant elements allow the system to accumulate failures which are repaired during the routine maintenance. The process of system operational status changes is described with the discrete-continuous model in the flight time. Basing on the information about the probabilities of the on-board equipment being in an operable, extreme or failed state, it is possible to calculate such complex efficiency indicators as the average loss of sorties, the average operating costs, the expected number of emergency recovery operations and others. Numerical studies have been conducted to validate the proposed model. It is believed that maintenance work completely updates the system. The analysis of these indicators will allow to evaluate the maintenance-free aircraft equipment operation efficiency, as well as to make an effectiveness comparison with other methods of technical operation. The model can be also used to assess the technical operation systems performance. The model can be used to optimize the period between maintenance.

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

Science.gov (United States)

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

2018-02-01

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

BINARY PARTICLE SWARM OPTIMIZATION APPROACH FOR RANDOM GENERATION OUTAGE MAINTENANCE SCHEDULING

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K. Suresh

2013-01-01

Full Text Available This paper presents a methodology for maintenance scheduling (MS of generators using binary particle swarm optimization (BPSO based probabilistic approach. The objective of this paper is to reduce the loss of load probability (LOLP for a power system. The capacity outage probability table (COPT is the initial step in creating maintenance schedule using the probabilistic levelized risk method. This paper proposes BPSO method which is used to construct the COPT. In order to mitigate the effects of probabilistic levelized risk method, BPSO based probabilistic levelized risk method is embarked on a MS problem. In order to validate the effectiveness of the proposed algorithm, case study results for simple five unit system can accomplish a significant levelization in the reliability indices that make possible to evaluate system generation system adequacy in the MS horizon of the power system. The proposed method shows better performance compared with other optimization methods and conventional method with improved search performance.

A probabilistic computational framework for bridge network optimal maintenance scheduling

International Nuclear Information System (INIS)

Bocchini, Paolo; Frangopol, Dan M.

2011-01-01

This paper presents a probabilistic computational framework for the Pareto optimization of the preventive maintenance applications to bridges of a highway transportation network. The bridge characteristics are represented by their uncertain reliability index profiles. The in/out of service states of the bridges are simulated taking into account their correlation structure. Multi-objective Genetic Algorithms have been chosen as numerical tool for the solution of the optimization problem. The design variables of the optimization are the preventive maintenance schedules of all the bridges of the network. The two conflicting objectives are the minimization of the total present maintenance cost and the maximization of the network performance indicator. The final result is the Pareto front of optimal solutions among which the managers should chose, depending on engineering and economical factors. A numerical example illustrates the application of the proposed approach.

Integrated batch production and maintenance scheduling for multiple items processed on a deteriorating machine to minimize total production and maintenance costs with due date constraint

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Zahedi Zahedi

2016-04-01

Full Text Available This paper discusses an integrated model of batch production and maintenance scheduling on a deteriorating machine producing multiple items to be delivered at a common due date. The model describes the trade-off between total inventory cost and maintenance cost as the increase of production run length. The production run length is a time bucket between two consecutive preventive maintenance activities. The objective function of the model is to minimize total cost consisting of in process and completed part inventory costs, setup cost, preventive and corrective maintenance costs and rework cost. The problem is to determine the optimal production run length and to schedule the batches obtained from determining the production run length in order to minimize total cost.

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

the level of the system optimization. By means of this equipment, managers can benefit from a condition-based maintenance (CBM) for monitoring and managing their system. The chief aim of the paper is to develop a stochastic maintenance problem based on CBM activities engaged with a complex applied......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 enhancing...... production problem called flexible job shop scheduling problem (FJSP). This integrated problem considers two maintenance scenarios in terms of corrective maintenance (CM) and preventive maintenance (PM). The activation of scenario is done by monitoring the degradation condition of the system and comparing...

Strategic Maintenance Scheduling of an Offshore Wind Farm in a Deregulated Power System

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Peyman Mazidi

2017-03-01

Full Text Available This paper proposes a model for strategic maintenance scheduling of offshore wind farms (SMSOWF in a deregulated power system. The objective of the model is to plan the maintenance schedules in a way to maximize the profit of the offshore wind farm. In addition, some network constraints, such as transmission lines capacity, and wind farm constraints, such as labor working shift, wave height limit and wake effect, as well as unexpected outages, are included in deterministic and stochastic studies. Moreover, the proposedmodel provides theability to incorporate information from condition monitoring systems. SMSOWF is formulated through a bi-level formulation and then transformed into a single-level through Karush–Kuhn–Tucker conditions. The model is validated through a test system, and the results demonstrate applicability, advantages and challenges of harnessing the full potential of the model.

A manpower scheduling heuristic for aircraft maintenance application

Science.gov (United States)

Sze, San-Nah; Sze, Jeeu-Fong; Chiew, Kang-Leng

2012-09-01

This research studies a manpower scheduling for aircraft maintenance, focusing on in-flight food loading operation. A group of loading teams with flexible shifts is required to deliver and upload packaged meals from the ground kitchen to aircrafts in multiple trips. All aircrafts must be served within predefined time windows. The scheduling process takes into account of various constraints such as meal break allocation, multi-trip traveling and food exposure time limit. Considering the aircrafts movement and predefined maximum working hours for each loading team, the main objective of this study is to form an efficient roster by assigning a minimum number of loading teams to the aircrafts. We proposed an insertion based heuristic to generate the solutions in a short period of time for large instances. This proposed algorithm is implemented in various stages for constructing trips due to the presence of numerous constraints. The robustness and efficiency of the algorithm is demonstrated in computational results. The results show that the insertion heuristic more efficiently outperforms the company's current practice.

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

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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.

Distributed decision-making in electric power system transmission maintenance scheduling using multi-agent systems (MAS)

Science.gov (United States)

Zhang, Zhong

In this work, motivated by the need to coordinate transmission maintenance scheduling among a multiplicity of self-interested entities in restructured power industry, a distributed decision support framework based on multiagent negotiation systems (MANS) is developed. An innovative risk-based transmission maintenance optimization procedure is introduced. Several models for linking condition monitoring information to the equipment's instantaneous failure probability are presented, which enable quantitative evaluation of the effectiveness of maintenance activities in terms of system cumulative risk reduction. Methodologies of statistical processing, equipment deterioration evaluation and time-dependent failure probability calculation are also described. A novel framework capable of facilitating distributed decision-making through multiagent negotiation is developed. A multiagent negotiation model is developed and illustrated that accounts for uncertainty and enables social rationality. Some issues of multiagent negotiation convergence and scalability are discussed. The relationships between agent-based negotiation and auction systems are also identified. A four-step MAS design methodology for constructing multiagent systems for power system applications is presented. A generic multiagent negotiation system, capable of inter-agent communication and distributed decision support through inter-agent negotiations, is implemented. A multiagent system framework for facilitating the automated integration of condition monitoring information and maintenance scheduling for power transformers is developed. Simulations of multiagent negotiation-based maintenance scheduling among several independent utilities are provided. It is shown to be a viable alternative solution paradigm to the traditional centralized optimization approach in today's deregulated environment. This multiagent system framework not only facilitates the decision-making among competing power system entities, but

Constrained non-linear multi-objective optimisation of preventive maintenance scheduling for offshore wind farms

Science.gov (United States)

Zhong, Shuya; Pantelous, Athanasios A.; Beer, Michael; Zhou, Jian

2018-05-01

Offshore wind farm is an emerging source of renewable energy, which has been shown to have tremendous potential in recent years. In this blooming area, a key challenge is that the preventive maintenance of offshore turbines should be scheduled reasonably to satisfy the power supply without failure. In this direction, two significant goals should be considered simultaneously as a trade-off. One is to maximise the system reliability and the other is to minimise the maintenance related cost. Thus, a non-linear multi-objective programming model is proposed including two newly defined objectives with thirteen families of constraints suitable for the preventive maintenance of offshore wind farms. In order to solve our model effectively, the nondominated sorting genetic algorithm II, especially for the multi-objective optimisation is utilised and Pareto-optimal solutions of schedules can be obtained to offer adequate support to decision-makers. Finally, an example is given to illustrate the performances of the devised model and algorithm, and explore the relationships of the two targets with the help of a contrast model.

Considerations on operation schedule and maintenance aspects of FCC-hh

CERN Document Server

Niemi, Arto; Foraz, Katy

2018-01-01

The Future Circular Hadron Collider (FCC-hh) has ambitious goals for integrated luminosity production. Reaching these goals requires reducing the time for planned technical stops and commissioning, compared to the LHC. This note describes potential options for an FCC-hh operation schedule. Special attention is given to considerations on how to accomplish the required maintenance activities in a limited time frame. The note recommends to study further the feasibility and cost-efficiency of operating without annual stops and longer intervals between long shutdowns.

Health Information Sources, Perceived Vaccination Benefits, and Maintenance of Childhood Vaccination Schedules.

Science.gov (United States)

Hwang, Juwon; Shah, Dhavan V

2018-06-05

Parental concerns over the safety or necessity of childhood vaccination have increased over the past decades. At the same time, there has been a proliferation of vaccine-related information available through a range of health information sources. This study investigates the associations between evaluations of health information sources, parental perceptions of childhood vaccination benefits, and the maintenance of vaccination schedules for their children. Specifically, this study aims to (a) incorporate social media into the battery of health information sources and (b) differentiate households with a childhood autism diagnosis and those without, given unsubstantiated but persistent concerns about vaccine safety and autism. Analyzing a sample of U.S. households, a total of 4,174 parents who have at least one child under the age of 18 were analyzed, including 138 of parents of households with a childhood autism diagnosis. Results show that the more the parents value interpersonal communication and magazines as sources of health information, the more they perceive vaccination benefits, and the more the value they put on television, the better they keep vaccination schedules up-to-date for their children. On the other hand, social media are negatively associated with their perceptions of vaccination benefits. Although parents of children diagnosed with autism are less likely to perceive vaccination benefits, no interaction effects with evaluations of health information sources are found on parental perceptions of vaccination benefits or maintenance of schedules.

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)

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

Science.gov (United States)

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

2012-01-01

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

Multiobjective Joint Optimization of Production Scheduling and Maintenance Planning in the Flexible Job-Shop Problem

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Jianfei Ye

2015-01-01

Full Text Available In order to solve the joint optimization of production scheduling and maintenance planning problem in the flexible job-shop, a multiobjective joint optimization model considering the maximum completion time and maintenance costs per unit time is established based on the concept of flexible job-shop and preventive maintenance. A weighted sum method is adopted to eliminate the index dimension. In addition, a double-coded genetic algorithm is designed according to the problem characteristics. The best result under the circumstances of joint decision-making is obtained through multiple simulation experiments, which proves the validity of the algorithm. We can prove the superiority of joint optimization model by comparing the result of joint decision-making project with the result of independent decision-making project under fixed preventive maintenance period. This study will enrich and expand the theoretical framework and analytical methods of this problem; it provides a scientific decision analysis method for enterprise to make production plan and maintenance plan.

JIT single machine scheduling problem with periodic preventive maintenance

Science.gov (United States)

Shahriari, Mohammadreza; Shoja, Naghi; Zade, Amir Ebrahimi; Barak, Sasan; Sharifi, Mani

2016-09-01

This article investigates a JIT single machine scheduling problem with a periodic preventive maintenance. Also to maintain the quality of the products, there is a limitation on the maximum number of allowable jobs in each period. The proposed bi-objective mixed integer model minimizes total earliness-tardiness and makespan simultaneously. Due to the computational complexity of the problem, multi-objective particle swarm optimization (MOPSO) algorithm is implemented. Also, as well as MOPSO, two other optimization algorithms are used for comparing the results. Eventually, Taguchi method with metrics analysis is presented to tune the algorithms' parameters and a multiple criterion decision making technique based on the technique for order of preference by similarity to ideal solution is applied to choose the best algorithm. Comparison results confirmed the supremacy of MOPSO to the other algorithms.

77 FR 488 - Control of Emissions From New Highway Vehicles and Engines; Approval of New Scheduled Maintenance...

Science.gov (United States)

2012-01-05

... (e.g., dump trucks, concrete mixers, refuse trucks, and other centrally-fueled vehicles) were... intervals for DEF-based SCR. For vocational vehicles such as dump trucks, concrete mixers, refuse trucks and... Engines; Approval of New Scheduled Maintenance for Selective Catalytic Reduction Technologies AGENCY...

Applying the TOC Project Management to Operation and Maintenance Scheduling of a Research Vessel

Science.gov (United States)

Manti, M. Firdausi; Fujimoto, Hideo; Chen, Lian-Yi

Marine research vessels and their systems are major assets in the marine resources development. Since the running costs for the ship are very high, it is necessary to reduce the total cost by an efficient scheduling for operation and maintenance. To reduce project period and make it efficient, we applied TOC project management method that is a project management approach developed by Dr. Eli Goldratt. It challenges traditional approaches to project management. It will become the most important improvement in the project management since the development of PERT and critical path methodologies. As a case study, we presented the marine geology research project for the purpose of operations in addition to repair on the repairing dock projects for maintenance of vessels.

Pavement maintenance scheduling using genetic algorithms

OpenAIRE

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

2015-01-01

This paper presents a new pavement management system (PMS) to achieve the optimal pavement maintenance and rehabilitation (M&R) strategy for a highway network using genetic algorithms (GAs). Optimal M&R strategy is a set of pavement activities that both minimise the maintenance cost of a highway network and maximise the pavement condition of the road sections on the network during a certain planning period. NSGA-II, a multi-objective GA, is employed to perform pavement maintenance optimisatio...

The comparison of predictive scheduling algorithms for different sizes of job shop scheduling problems

Science.gov (United States)

Paprocka, I.; Kempa, W. M.; Grabowik, C.; Kalinowski, K.; Krenczyk, D.

2016-08-01

In the paper a survey of predictive and reactive scheduling methods is done in order to evaluate how the ability of prediction of reliability characteristics influences over robustness criteria. The most important reliability characteristics are: Mean Time to Failure, Mean Time of Repair. Survey analysis is done for a job shop scheduling problem. The paper answers the question: what method generates robust schedules in the case of a bottleneck failure occurrence before, at the beginning of planned maintenance actions or after planned maintenance actions? Efficiency of predictive schedules is evaluated using criteria: makespan, total tardiness, flow time, idle time. Efficiency of reactive schedules is evaluated using: solution robustness criterion and quality robustness criterion. This paper is the continuation of the research conducted in the paper [1], where the survey of predictive and reactive scheduling methods is done only for small size scheduling problems.

A new multi-objective optimization model for preventive maintenance and replacement scheduling of multi-component systems

Science.gov (United States)

Moghaddam, Kamran S.; Usher, John S.

2011-07-01

In this article, a new multi-objective optimization model is developed to determine the optimal preventive maintenance and replacement schedules in a repairable and maintainable multi-component system. In this model, the planning horizon is divided into discrete and equally-sized periods in which three possible actions must be planned for each component, namely maintenance, replacement, or do nothing. The objective is to determine a plan of actions for each component in the system while minimizing the total cost and maximizing overall system reliability simultaneously over the planning horizon. Because of the complexity, combinatorial and highly nonlinear structure of the mathematical model, two metaheuristic solution methods, generational genetic algorithm, and a simulated annealing are applied to tackle the problem. The Pareto optimal solutions that provide good tradeoffs between the total cost and the overall reliability of the system can be obtained by the solution approach. Such a modeling approach should be useful for maintenance planners and engineers tasked with the problem of developing recommended maintenance plans for complex systems of components.

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

International Nuclear Information System (INIS)

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

2007-01-01

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

Using Integer Programming for Airport Service Planning in Staff Scheduling

Directory of Open Access Journals (Sweden)

W.H. Ip

2010-09-01

Full Text Available Reliability and safety in flight is extremely necessary and that depend on the adoption of proper maintenance system. Therefore, it is essential for aircraft maintenance companies to perform the manpower scheduling efficiently. One of the objectives of this paper is to provide an Integer Programming approach to determine the optimal solutions to aircraft maintenance planning and scheduling and hence the planning and scheduling processes can become more efficient and effective. Another objective is to develop a set of computational schedules for maintenance manpower to cover all scheduled flights. In this paper, a sequential methodology consisting of 3 stages is proposed. They are initial maintenance demand schedule, the maintenance pairing and the maintenance group(s assignment. Since scheduling would split up into different stages, different mathematical techniques have been adopted to cater for their own problem characteristics. Microsoft Excel would be used. Results from the first stage and second stage would be inputted into integer programming model using Microsoft Excel Solver to find the optimal solution. Also, Microsoft Excel VBA is used for devising a scheduling system in order to reduce the manual process and provide a user friendly interface. For the results, all can be obtained optimal solution and the computation time is reasonable and acceptable. Besides, the comparison of the peak time and non-peak time is discussed.

Modeling the Hybrid Flow Shop Scheduling Problem Followed by an Assembly Stage Considering Aging Effects and Preventive Maintenance Activities

Directory of Open Access Journals (Sweden)

Seyyed Mohammad Hassan Hosseini

2016-05-01

Full Text Available Scheduling problem for the hybrid flow shop scheduling problem (HFSP followed by an assembly stage considering aging effects additional preventive and maintenance activities is studied in this paper. In this production system, a number of products of different kinds are produced. Each product is assembled with a set of several parts. The first stage is a hybrid flow shop to produce parts. All machines can process all kinds of parts in this stage but each machine can process only one part at the same time. The second stage is a single assembly machine or a single assembly team of workers. The aim is to schedule the parts on the machines and assembly sequence and also determine when the preventive maintenance activities get done in order to minimize the completion time of all products (makespan. A mathematical modeling is presented and its validation is shown by solving an example in small scale. Since this problem has been proved strongly NP-hard, in order to solve the problem in medium and large scale, four heuristic algorithms is proposed based on the Johnson’s algorithm. The numerical experiments are used to run the mathematical model and evaluate the performance of the proposed algorithms.

The Offering, Scheduling and Maintenance of Elective Advanced Pharmacy Practice Experiences

Directory of Open Access Journals (Sweden)

Rex O. Brown

2015-12-01

Full Text Available The Accreditation Council for Pharmacy Education (ACPE provides standards for colleges of pharmacy to assist in the provision of pharmacy education to student pharmacists. An integral part of all college educational programs includes the provision of experiential learning. Experiential learning allows students to gain real-world experience in direct patient care during completion of the curriculum. All college of pharmacy programs provide several Advanced Pharmacy Practice Experiences (APPEs, which include a balance between the four required experiences and a number of other required or elective APPEs. Required APPEs include advanced community, advanced institutional, ambulatory care, and general medicine. The elective APPEs include a myriad of opportunities to help provide a balanced education in experiential learning for student pharmacists. These unique opportunities help to expose student pharmacists to different career tracks that they may not have been able to experience otherwise. Not all colleges offer enough elective APPEs to enable the student pharmacist to obtain experiences in a defined area. Such an approach is required to produce skilled pharmacy graduates that are capable to enter practice in various settings. Elective APPEs are scheduled logically and are based upon student career interest and site availability. This article describes the offering, scheduling and maintenance of different elective APPEs offered by The University of Tennessee College of Pharmacy.

The Development of Plant Maintenance Scheduling Via lnventory System for Sustainable Plant Operation

Directory of Open Access Journals (Sweden)

Masripan Roslizan

2016-01-01

Full Text Available Industrial sector becomes the main concern for developing country. By the time, it was increased rapidly. However, there are many problems observed such as maintenance scheduling, stock inventory and supply chain. Therefore, this research develops new inventory system to develop sustainable plant operation with a high capability to plant operation especially to stock inventory of machine component. In also required green application with minimised used on paper. This system is developed using Radio Frequency Identification (RFID for inventory control which integrated with web-based system. This system consists of several modules such as station module, item module and item request module and report of critical stock in the store. This system can be controlled from a hand-phone with internet connection or automatic alert such as Short Massage Send (SMS and email. The developed system is very effective in monitoring the stock material through the barcode, supply chain and worker performance as well as to reduce the lead time for maintenance activities of the company through sustainable plant operation.

The maintenance management framework models and methods for complex systems maintenance

CERN Document Server

Crespo Márquez, Adolfo

2010-01-01

“The Maintenance Management Framework” describes and reviews the concept, process and framework of modern maintenance management of complex systems; concentrating specifically on modern modelling tools (deterministic and empirical) for maintenance planning and scheduling. It will be bought by engineers and professionals involved in maintenance management, maintenance engineering, operations management, quality, etc. as well as graduate students and researchers in this field.

Outage scheduling and implementation

International Nuclear Information System (INIS)

Allison, J.E.; Segall, P.; Smith, R.R.

1986-01-01

Successful preparation and implementation of an outage schedule and completion of scheduled and emergent work within an identified critical path time frame is a result of careful coordination by Operations, Work Control, Maintenance, Engineering, Planning and Administration and others. At the Fast Flux Test Facility (FFTF) careful planning has been responsible for meeting all scheduled outage critical paths

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

Hybrid Particle Swarm Optimization for Hybrid Flowshop Scheduling Problem with Maintenance Activities

Science.gov (United States)

Li, Jun-qing; Pan, Quan-ke; Mao, Kun

2014-01-01

A hybrid algorithm which combines particle swarm optimization (PSO) and iterated local search (ILS) is proposed for solving the hybrid flowshop scheduling (HFS) problem with preventive maintenance (PM) activities. In the proposed algorithm, different crossover operators and mutation operators are investigated. In addition, an efficient multiple insert mutation operator is developed for enhancing the searching ability of the algorithm. Furthermore, an ILS-based local search procedure is embedded in the algorithm to improve the exploitation ability of the proposed algorithm. The detailed experimental parameter for the canonical PSO is tuning. The proposed algorithm is tested on the variation of 77 Carlier and Néron's benchmark problems. Detailed comparisons with the present efficient algorithms, including hGA, ILS, PSO, and IG, verify the efficiency and effectiveness of the proposed algorithm. PMID:24883414

Hybrid Particle Swarm Optimization for Hybrid Flowshop Scheduling Problem with Maintenance Activities

Directory of Open Access Journals (Sweden)

Jun-qing Li

2014-01-01

Full Text Available A hybrid algorithm which combines particle swarm optimization (PSO and iterated local search (ILS is proposed for solving the hybrid flowshop scheduling (HFS problem with preventive maintenance (PM activities. In the proposed algorithm, different crossover operators and mutation operators are investigated. In addition, an efficient multiple insert mutation operator is developed for enhancing the searching ability of the algorithm. Furthermore, an ILS-based local search procedure is embedded in the algorithm to improve the exploitation ability of the proposed algorithm. The detailed experimental parameter for the canonical PSO is tuning. The proposed algorithm is tested on the variation of 77 Carlier and Néron’s benchmark problems. Detailed comparisons with the present efficient algorithms, including hGA, ILS, PSO, and IG, verify the efficiency and effectiveness of the proposed algorithm.

Hybrid particle swarm optimization for hybrid flowshop scheduling problem with maintenance activities.

Science.gov (United States)

Li, Jun-qing; Pan, Quan-ke; Mao, Kun

2014-01-01

A hybrid algorithm which combines particle swarm optimization (PSO) and iterated local search (ILS) is proposed for solving the hybrid flowshop scheduling (HFS) problem with preventive maintenance (PM) activities. In the proposed algorithm, different crossover operators and mutation operators are investigated. In addition, an efficient multiple insert mutation operator is developed for enhancing the searching ability of the algorithm. Furthermore, an ILS-based local search procedure is embedded in the algorithm to improve the exploitation ability of the proposed algorithm. The detailed experimental parameter for the canonical PSO is tuning. The proposed algorithm is tested on the variation of 77 Carlier and Néron's benchmark problems. Detailed comparisons with the present efficient algorithms, including hGA, ILS, PSO, and IG, verify the efficiency and effectiveness of the proposed algorithm.

A hybrid Constraint Programming/Mixed Integer Programming framework for the preventive signaling maintenance crew scheduling problem

DEFF Research Database (Denmark)

Pour, Shahrzad M.; Drake, John H.; Ejlertsen, Lena Secher

2017-01-01

A railway signaling system is a complex and interdependent system which should ensure the safe operation of trains. We introduce and address a mixed integer optimisation model for the preventive signal maintenance crew scheduling problem in the Danish railway system. The problem contains many...... to feed as ‘warm start’ solutions to a Mixed Integer Programming (MIP) solver for further optimisation. We apply the CP/MIP framework to a section of the Danish rail network and benchmark our results against both direct application of a MIP solver and modelling the problem as a Constraint Optimisation...

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

A Planned Preventive Maintenance Program. A Handbook for Chief Business Officers and Supervisors of Maintenance with Suggestions on Maintenance for Consideration by Presidents of Higher Institutions.

Science.gov (United States)

Daniel, Clarence H.

This handbook explains planned preventive maintenance program, which is an operational system of maintenance designed to increase the effectiveness of the maintenance staff and the use of maintenance funds through efficient scheduling of inspections and follow-through of work to be performed. Sections are included for the chief administrative…

Maintenance cost models in deregulated power systems under opportunity costs

International Nuclear Information System (INIS)

Al-Arfaj, K.; Dahal, K.; Azaiez, M.N.

2007-01-01

In a centralized power system, the operator is responsible for scheduling maintenance. There are different types of maintenance, including corrective maintenance; predictive maintenance; preventive maintenance; and reliability-centred maintenance. The main cause of power failures is poor maintenance. As such, maintenance costs play a significant role in deregulated power systems. They include direct costs associated with material and labor costs as well as indirect costs associated with spare parts inventory, shipment, test equipment, indirect labor, opportunity costs and cost of failure. In maintenance scheduling and planning, the cost function is the only component of the objective function. This paper presented the results of a study in which different components of maintenance costs were modeled. The maintenance models were formulated as an optimization problem with single and multiple objectives and a set of constraints. The maintenance costs models could be used to schedule the maintenance activities of power generators more accurately and to identify the best maintenance strategies over a period of time as they consider failure and opportunity costs in a deregulated environment. 32 refs., 4 tabs., 4 figs

STARFIRE remote maintenance and reactor facility concept

International Nuclear Information System (INIS)

Graumann, D.W.; Field, R.E.; Lutz, G.R.; Trachsel, C.A.

1981-01-01

A total remote maintenance facility has been designed for all equipment located within the reactor building and hot cell, although operational flexibility has been provided by design of the reactor shielding such that personnel access into the reactor building within 24 hours after reactor shutdown is possible. The reactor design permits removal and replacement of all components if necessary, however, the vacuum pumps, isolation valves and blanket require scheduled, routine maintenance. Reactor scheduled maintenance does not dominate annual plant downtime, therefore, several scheduled operations can be added without affecting reactor availability. The maintenance facilities consist of the reactor building, the hot cell, the reactor service area and the remote maintenance control room. The reactor building contains the reactor, selected support system modules, and required maintenance equipment. The reactor and the support systems are maintained with (1) equipment that is mounted on a monorail system; (2) overhead cranes; and (3) bridge-mounted electromechanical manipulators. The hot cell is located outside of the reactor building to localize contamination products and permit independent operation. An equipment air lock connects the reactor building to the hot cell

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

International Nuclear Information System (INIS)

Courtois, Pierre-Jacques; Delsarte, Philippe

2006-01-01

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

Robust scheduling in an uncertain environment

NARCIS (Netherlands)

Wilson, M.

2016-01-01

This thesis presents research on scheduling in an uncertain environment, which forms a part of the rolling stock life cycle logistics applied research and development program funded by Dutch railway industry companies. The focus therefore lies on scheduling of maintenance operations on rolling stock

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...

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...

Use of probabilistic risk assessment in maintenance activities at Palo Verde

International Nuclear Information System (INIS)

Lindquist, R.C.; Pobst, D.S.

1993-01-01

Probabilistic risk assessment (PRA) is an important tool in addressing various maintenance activities. At the Palo Verde nuclear generating station (PVNGS), the PRA has been used in a variety of ways to support a wide and diverse selection of maintenance-related activities. For on-line or at-power maintenance, the PRA was used to evaluate combinations of maintenance activities possible with the 12-week or floating maintenance schedule. The maintenance schedule was evaluated to identify any higher risk, undesirable combinations of equipment outages, such as the sole steam-driven auxiliary feedwater pump and the same train emergency diesel generator. Table I is a sampling of the results from the maintenance schedule evaluation in terms of increase in conditional core damage frequency (CDF) above the base- line value due to maintenance on some important key safety systems and combinations thereof. The baseline CDF is 7.4 x 10 -7 per 72 h

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.

Reliability-based maintenance evaluations and standard preventive maintenance programs

International Nuclear Information System (INIS)

Varno, M.; McKinley, M.

1993-01-01

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

Influence of titration schedule and maintenance dose on the tolerability of adjunctive eslicarbazepine acetate: An integrated analysis of three randomized placebo-controlled trials.

Science.gov (United States)

Krauss, Gregory; Biton, Victor; Harvey, Jay H; Elger, Christian; Trinka, Eugen; Soares da Silva, Patrício; Gama, Helena; Cheng, Hailong; Grinnell, Todd; Blum, David

2018-01-01

To examine the influence of titration schedule and maintenance dose on the incidence and type of treatment-emergent adverse events (TEAEs) associated with adjunctive eslicarbazepine acetate (ESL). Data from three randomized, double-blind, placebo-controlled trials were analyzed. Patients with refractory partial-onset seizures were randomized to maintenance doses of ESL 400, 800, or 1200mg QD (dosing was initiated at 400 or 800mg QD) or placebo. The incidence of TEAEs was analyzed during the double-blind period (2-week titration phase; 12-week maintenance phase), according to the randomized maintenance dose and the titration schedule. 1447 patients were included in the analysis. During the first week of treatment, 62% of patients taking ESL 800mg QD had ≥1 TEAE, vs 35% of those taking 400mg QD and 32% of the placebo group; dizziness, somnolence, nausea, and headache were numerically more frequent in patients taking ESL 800mg than those taking ESL 400mg QD. During the double-blind period, the incidences of common TEAEs were lower in patients who initiated ESL at 400mg vs 800mg QD. For the 800 and 1200mg QD maintenance doses, rates of TEAEs leading to discontinuation were lower in patients who began treatment with 400mg than in those who began taking ESL 800mg QD. Initiation of ESL at 800mg QD is feasible. However, initiating treatment with ESL 400mg QD for 1 or 2 weeks is recommended, being associated with a lower incidence of TEAEs, and related discontinuations. For some patients, treatment may be initiated at 800mg QD, if the need for more immediate seizure reduction outweighs concerns about increased risk of adverse reactions during initiation. Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.

A VITAL service for predictive MOV maintenance

International Nuclear Information System (INIS)

Anon.

1990-01-01

Motor-operated valve (MOV) maintenance can be a major contributor to unplanned plant downtime, either because valve malfunctions cause unscheduled outages, or because unnecessary valve maintenance lengthens scheduled outages. The cause of both situations is a preventive approach to valve maintenance, where maintenance is scheduled according to a timetable instead of according to a demonstrated need. To move towards a predictive maintenance approach, inexpensive methods of collecting and diagnosing real-time data on the conditions of a valve must be made available. Such a system must be capable of detecting and diagnosing degrading mechanical and electrical behaviour at an early stage, as well as being able to predict the time of failure. Without this data, a predictive approach to maintenance is impossible. Westinghouse is addressing the requirements for a predictive approach to MOV maintenance with the introduction of a third-generation of diagnostic systems for motor-operated valves -the portable Valve Intelligent Test and Analysis System (VITALS) and the on-line Valve Monitoring System (VMS). (author)

Constraint-based scheduling

Science.gov (United States)

Zweben, Monte

1993-01-01

The GERRY scheduling system developed by NASA Ames with assistance from the Lockheed Space Operations Company, and the Lockheed Artificial Intelligence Center, uses a method called constraint-based iterative repair. Using this technique, one encodes both hard rules and preference criteria into data structures called constraints. GERRY repeatedly attempts to improve schedules by seeking repairs for violated constraints. The system provides a general scheduling framework which is being tested on two NASA applications. The larger of the two is the Space Shuttle Ground Processing problem which entails the scheduling of all the inspection, repair, and maintenance tasks required to prepare the orbiter for flight. The other application involves power allocation for the NASA Ames wind tunnels. Here the system will be used to schedule wind tunnel tests with the goal of minimizing power costs. In this paper, we describe the GERRY system and its application to the Space Shuttle problem. We also speculate as to how the system would be used for manufacturing, transportation, and military problems.

Concurrent immunomodulator therapy is associated with higher adalimumab trough levels during scheduled maintenance therapy.

Science.gov (United States)

Bond, Ashley; Dodd, Susanna; Fisher, Gareth; Skouras, Thomas; Subramanian, Sreedhar

2017-02-01

Combination therapy with infliximab and immunomodulators is superior to monotherapy, resulting in better outcomes and higher trough levels of infliximab. The role of concurrent immunomodulatory therapy on adalimumab trough levels has not been adequately investigated. We evaluated the impact of concomitant immunomodulation on adalimumab trough levels in patients on scheduled maintenance therapy. We conducted a prospective observational, cross-sectional study of all inflammatory bowel disease patients on maintenance therapy who had adalimumab trough levels measured between January 2013 and January 2016. Drug level and anti-drug antibody measurements were performed on sera using a solid phase assay. Pairwise comparison of means was used to compare trough levels in patients with and without concomitant immune modulator therapy. In total, 79 patients were included. Twenty-three patients (29.1%) were on weekly dosing whereas 56 (70.9%) were on alternate weeks. Median adalimumab trough levels were comparable in patients with and without clinical remission (6.8 μg/ml (IQR 5.6-8.1) versus 6.7 μg/ml (IQR 3.9-8.1), respectively. Patients with an elevated faecal calprotectin >250 μg/g had lower adalimumab trough levels (median 6.7, IQR 3.9-8) compared to patients with faecal calprotectin <250 μg/g (median 7.7, IQR 6.1-8.1) though this did not achieve statistical significance (p = .062). Median adalimumab trough levels among patients on concurrent immunomodulators was 7.2 μg/ml (IQR 5.7-8.1) compared to those not on concurrent immunomodulator, 6.1 μg/ml (IQR 2.7-7.7, p = .0297). Adalimumab trough levels were significantly higher in patients on concurrent immunomodulators during maintenance therapy. There was a trend towards a lower adalimumab trough level in patients with elevated calprotectin.

Maintenance scheduling of a manufacturing system subject to deterioration

International Nuclear Information System (INIS)

Ahmadi, Reza; Newby, Martin

2011-01-01

This paper presents an integrated model for the joint determination of both optimal inspection strategy and optimal repair policy for a manufacturing system whose resulting output is subject to system state. An appropriate maintenance strategy is essential to optimize revenue from a manufacturing system which is in continuous operation and subject to deterioration. The optimum policy balances the amount of maintenance required to increase availability against the loss of revenue arising from the down time: insufficient maintenance leads to an increase in the number of defective items, low profit and low maintenance cost; excessive maintenance results in a reduction in the proportion of defective items, high profit and high maintenance cost. In this paper, an intensity control model adapted to partial information provides an optimal inspection intensity and repair degree of the system as an optimal control process to yield maximum revenue. The solution is obtained through formulating an equivalent deterministic Hamilton-Jacobi equation. A numerical example is provided to illustrate the behavior of the optimal control process. The optimal control process determines a solution to both optimum inspection frequency and optimal replacement policy which results in an optimal production run length of the system. - Highlights: → We develop an optimum asset management strategy based on the revenue generated by the asset. → The optimum strategy controls the intensity, rate of occurrence, of interruptions to service. → The decisions are based on partial observation of the system and do not need perfect information. There is no need for continuous monitoring of the system.

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

Science.gov (United States)

Witantyo; Rindiyah, Anita

2018-03-01

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

Modularity Design Approach for Preventive Machine Maintenance

Science.gov (United States)

Ernawati, D.; Pudji, E.; Ngatilah, Y.; Handoyo, R.

2018-01-01

In a company, machine maintenance system will be very influential in production process activity. The company should have a scheduled engine maintenance system that does not require high costs when repairing and replacing machine parts. Modularity Design method is able to provide solutions to the engine maintenance scheduling system and can prevent fatal damage to the engine components. It can minimize the cost of repair and replacement of these machine components.The paper provides a solution to machine maintenance problems. The paper is also completed with case study of milling machines. That case studies can give us a real description about impact implementation of modularity design to prevent fatal damage to components and minimize the cost of repair and replacement of components of the machine.

Generation maintenance scheduling based on multiple ob jectives and their relationship analysis

Institute of Scientific and Technical Information of China (English)

Jun-peng ZHAN; Chuang-xin GUO; Qing-hua WU; Lu-liang ZHANG; Hong-jun FU

2014-01-01

In a market environment of power systems, each producer pursues its maximal profit while the independent system operator is in charge of the system reliability and the minimization of the total generation cost when generating the generation maintenance scheduling (GMS). Thus, the GMS is inherently a multi-objective optimization problem as its objectives usually conflict with each other. This paper proposes a multi-objective GMS model in a market environment which includes three types of objectives, i.e., each producer’s profit, the system reliability, and the total generation cost. The GMS model has been solved by the group search optimizer with multiple producers (GSOMP) on two test systems. The simulation results show that the model is well solved by the GSOMP with a set of evenly distributed Pareto-optimal solutions obtained. The simulation results also illustrate that one producer’s profit conflicts with another one’s, that the total generation cost does not conflict with the profit of the producer possessing the cheapest units while the total generation cost conflicts with the other producers’ profits, and that the reliability objective conflicts with the other objectives.

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)

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...

Towards Signalling Maintenance Scheduling for European Railway Traffic Management System

DEFF Research Database (Denmark)

M. Pour, Shahrzad

signalling system. Therefore, the entire maintenance system needs to change from the previous system to the newest system, and hence, new optimisation techniques need to be established so as to facilitate managers in creating ideal maintenance strategies. The aim of this thesis is to develop new maintenance......The European Railway Traffic Management System (ERTMS) is the newest signalling standard that has been introduced in the railway industry. The aim of ERTMS is to ensure better signalling communication amongst various train systems, and hence, to help in attaining improved connectivity and commuting...... between European countries. In various countries across the world, there is a gradual shift from the current signalling systems to ERTMS. Amongst the European countries, Denmark was the first country to commence a full upgrading of its signalling system to ERTMS. A variety of maintenance requirements...

NRC comprehensive records disposition schedule

International Nuclear Information System (INIS)

1992-03-01

Title 44 United States Code, ''Public Printing and Documents,'' regulations cited in the General Services Administration's (GSA) ''Federal Information Resources Management Regulations'' (FIRMR), Part 201-9, ''Creation, Maintenance, and Use of Records,'' and regulation issued by the National Archives and Records Administration (NARA) in 36 CFR Chapter XII, Subchapter B, ''Records Management,'' require each agency to prepare and issue a comprehensive records disposition schedule that contains the NARA approved records disposition schedules for records unique to the agency and contains the NARA's General Records Schedules for records common to several or all agencies. The approved records disposition schedules specify the appropriate duration of retention and the final disposition for records created or maintained by the NRC. NUREG-0910, Rev. 2, contains ''NRC's Comprehensive Records Disposition Schedule,'' and the original authorized approved citation numbers issued by NARA. Rev. 2 totally reorganizes the records schedules from a functional arrangement to an arrangement by the host office. A subject index and a conversion table have also been developed for the NRC schedules to allow staff to identify the new schedule numbers easily and to improve their ability to locate applicable schedules

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

Cost effective shift schedules enhance utility operations

International Nuclear Information System (INIS)

Coleman, R.M.

1995-01-01

This article describes how new shift scheduling concepts can save utility operations millions of dollars every year and yet maintain safety and improve employee morale. The key to scheduling is to define and match the work load. This includes discretionary as well as daily, weekly, and yearly core work loads. In most power plants the overall work load (including maintenance, operations, materials handling, etc.) on day shift is greater than on other shifts, hence an unbalanced schedule would be appropriate

design of preventive maintenance scheduling model for ...

African Journals Online (AJOL)

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

A review of planning models for maintenance and production.

NARCIS (Netherlands)

G. Budai-Balke (Gabriella); R. Dekker (Rommert); R.P. Nicolai (Robin)

2006-01-01

textabstractIn this article we give an overview of the relation between planning of maintenance and production. On the one hand we consider production planning and scheduling models in which failures and maintenance aspects are taken into account. Next we discuss the planning of maintenance

The Composition of the Master Schedule

Science.gov (United States)

Thomas, Cynthia C.; Behrend, Dirk; MacMillan, Daniel S.

2010-01-01

Over a period of about four months, the IVS Coordinating Center (IVSCC) each year composes the Master Schedule for the IVS observing program of the next calendar year. The process begins in early July when the IVSCC contacts the IVS Network Stations to request information about available station time as well as holiday and maintenance schedules for the upcoming year. Going through various planning stages and a review process with the IVS Observing Program Committee (OPC), the final version of the Master Schedule is posted by early November. We describe the general steps of the composition and illustrate them with the example of the planning for the Master Schedule of the 2010 observing year.

Optimal infrastructure maintenance scheduling problem under budget uncertainty.

Science.gov (United States)

2010-05-01

This research addresses a general class of infrastructure asset management problems. Infrastructure : agencies usually face budget uncertainties that will eventually lead to suboptimal planning if : maintenance decisions are made without taking the u...

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

Fault Sample Generation for Virtual Testability Demonstration Test Subject to Minimal Maintenance and Scheduled Replacement

Directory of Open Access Journals (Sweden)

Yong Zhang

2015-01-01

Full Text Available Virtual testability demonstration test brings new requirements to the fault sample generation. First, fault occurrence process is described by stochastic process theory. It is discussed that fault occurrence process subject to minimal repair is nonhomogeneous Poisson process (NHPP. Second, the interarrival time distribution function of the next fault event is proposed and three typical kinds of parameterized NHPP are discussed. Third, the procedure of fault sample generation is put forward with the assumptions of minimal maintenance and scheduled replacement. The fault modes and their occurrence time subject to specified conditions and time period can be obtained. Finally, an antenna driving subsystem in automatic pointing and tracking platform is taken as a case to illustrate the proposed method. Results indicate that both the size and structure of the fault samples generated by the proposed method are reasonable and effective. The proposed method can be applied to virtual testability demonstration test well.

A solution approach based on Benders decomposition for the preventive maintenance scheduling problem of a stochastic large-scale energy system

DEFF Research Database (Denmark)

Lusby, Richard Martin; Muller, Laurent Flindt; Petersen, Bjørn

2013-01-01

This paper describes a Benders decomposition-based framework for solving the large scale energy management problem that was posed for the ROADEF 2010 challenge. The problem was taken from the power industry and entailed scheduling the outage dates for a set of nuclear power plants, which need...... to be regularly taken down for refueling and maintenance, in such away that the expected cost of meeting the power demand in a number of potential scenarios is minimized. We show that the problem structure naturally lends itself to Benders decomposition; however, not all constraints can be included in the mixed...

Operations Research Models for Scheduling Railway Infrastructure Maintenance

NARCIS (Netherlands)

G. Budai-Balke (Gabriella)

2009-01-01

textabstractIn the last decades, maintenance of technical systems has become increasingly impor- tant in many industries. Such systems are transport systems (rail, bus, airplane), civil engineering systems (roads, buildings, bridges), health care (hospitals), communication systems, manufacturing

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)

Optimization of maintenance scheduling with genetic algorithms regarding the storage behavior during the availability prognosis of power plants; Optimierung der Instandhaltungsplanung mit genetischen Algorithmen unter Beruecksichtigung des Speicherverhaltens bei der Verfuegbarkeitsprognose von Kraftwerksanlagen

Energy Technology Data Exchange (ETDEWEB)

Warnecke, Martin

2008-12-19

In the age of the liberalized energy market the power plant raisers and operators have to consider several factors when choosing the fuel type and dimensioning their power plants, e.g. emissions, erection cost and last but not least operating cost. Simulations assuming different scenarios are required. The rivaling aspects of erection cost, partially dependant availability, maintenance philosophy and operating cost are motivating the optimization of maintenance scheduling and the availability prognosis which are the topic of this thesis. The focus of this thesis is on the scheduling of the time based maintenance strategy. This strategy defines the time spans between the repeating inspections of each component. This is based on the experience of operators and manufacturers. The mathematic problem itself is especially challenging because of strong interdependencies between the single components due to synergy effects. Each component has its own theoretically optimal lifetime and maintenance period. Yet as part of a compound it might be more cost efficient in the long run to maintain some components together shifting some of them forward or backward. The thereby caused interdependencies constitute a non-linear, mixed-whole-numbered calculation of the cost approximation. For the optimization of this maintenance scheduling a new approach was developed. It was realized that the problem couldn't be solved satisfyingly with classic optimization algorithms. Afterwards a solution based on ''genetic algorithms'' was developed. In the meantime the methods for the availability prognosis of complex power plant facilities were enhanced. Especially a new component with storage behavior (with optional losses) was added to the prognosis tool. This storage model integrates the behavior of a storage into the computing time reduced Monte-Carlo-Method. (orig.)

Conception of Self-Construction Production Scheduling System

Science.gov (United States)

Xue, Hai; Zhang, Xuerui; Shimizu, Yasuhiro; Fujimura, Shigeru

With the high speed innovation of information technology, many production scheduling systems have been developed. However, a lot of customization according to individual production environment is required, and then a large investment for development and maintenance is indispensable. Therefore now the direction to construct scheduling systems should be changed. The final objective of this research aims at developing a system which is built by it extracting the scheduling technique automatically through the daily production scheduling work, so that an investment will be reduced. This extraction mechanism should be applied for various production processes for the interoperability. Using the master information extracted by the system, production scheduling operators can be supported to accelerate the production scheduling work easily and accurately without any restriction of scheduling operations. By installing this extraction mechanism, it is easy to introduce scheduling system without a lot of expense for customization. In this paper, at first a model for expressing a scheduling problem is proposed. Then the guideline to extract the scheduling information and use the extracted information is shown and some applied functions are also proposed based on it.

A production model and maintenance planning model for the process industry

NARCIS (Netherlands)

Ashayeri, J.; Teelen, A.; Selen, W.J.

1995-01-01

In this paper a model is developed to simultaneously plan preventive maintenance and production in a process industry environment, where maintenance planning is extremely important. The model schedules production jobs and preventive maintenance jobs, while minimizing costs associated with

Cost Minimization for Joint Energy Management and Production Scheduling Using Particle Swarm Optimization

Science.gov (United States)

Shah, Rahul H.

Production costs account for the largest share of the overall cost of manufacturing facilities. With the U.S. industrial sector becoming more and more competitive, manufacturers are looking for more cost and resource efficient working practices. Operations management and production planning have shown their capability to dramatically reduce manufacturing costs and increase system robustness. When implementing operations related decision making and planning, two fields that have shown to be most effective are maintenance and energy. Unfortunately, the current research that integrates both is limited. Additionally, these studies fail to consider parameter domains and optimization on joint energy and maintenance driven production planning. Accordingly, production planning methodology that considers maintenance and energy is investigated. Two models are presented to achieve well-rounded operating strategy. The first is a joint energy and maintenance production scheduling model. The second is a cost per part model considering maintenance, energy, and production. The proposed methodology will involve a Time-of-Use electricity demand response program, buffer and holding capacity, station reliability, production rate, station rated power, and more. In practice, the scheduling problem can be used to determine a joint energy, maintenance, and production schedule. Meanwhile, the cost per part model can be used to: (1) test the sensitivity of the obtained optimal production schedule and its corresponding savings by varying key production system parameters; and (2) to determine optimal system parameter combinations when using the joint energy, maintenance, and production planning model. Additionally, a factor analysis on the system parameters is conducted and the corresponding performance of the production schedule under variable parameter conditions, is evaluated. Also, parameter optimization guidelines that incorporate maintenance and energy parameter decision making in the

Instrumentation maintenance

International Nuclear Information System (INIS)

Mack, D.A.

1976-09-01

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

Excellence through outage planning and scheduling

International Nuclear Information System (INIS)

Ferriole, G.

1987-01-01

The Nuclear and Fossil Generation Division of Electricite de France (EdF) has been the largest nuclear plant operating utility in France since 1984. The size of the units, their standardization, and extensive operating experience were favorable parameters leading to the development of a very complete maintenance organization. Electricite de France believes in the importance of well-defined maintenance concepts. These maintenance concepts contribute to outage performance by requiring a careful consideration of work to be done and by defining the techniques and means of accomplishing this work. In addition to maintenance concepts and careful planning and scheduling, good outage management is achieved through the motivation and dedication of the people involved. It is the key to good operational results

Development of blanket remote maintenance system

International Nuclear Information System (INIS)

Kakudate, Satoshi; Nakahira, Masataka; Oka, Kiyoshi; Taguchi, Kou

1998-01-01

ITER in-vessel components such as blankets are scheduled maintenance components, including complete shield blanket replacement for breeding blankets. In-vessel components are activated by 14 MeV neutrons, so blanket maintenance requires remote handling equipment and tools able to handle heavy payloads of about 4 tons within a positioning accuracy of 2 mm under intense gamma radiation. To facilitate remote maintenance, blankets are segmented into 730 modules and rail-mounted vehicle remote maintenance was developed. According to the ITER R and D program, critical technology related to blanket maintenance was developed extensively through joint efforts of the Japan, EU, and U.S. home teams. This paper summarizes current blanket maintenance technology conducted by the Japan Home Team, including development of full-scale remote handling equipment and tools for blanket maintenance. (author)

Development of blanket remote maintenance system

Energy Technology Data Exchange (ETDEWEB)

Kakudate, Satoshi; Nakahira, Masataka; Oka, Kiyoshi; Taguchi, Kou [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment

1998-04-01

ITER in-vessel components such as blankets are scheduled maintenance components, including complete shield blanket replacement for breeding blankets. In-vessel components are activated by 14 MeV neutrons, so blanket maintenance requires remote handling equipment and tools able to handle heavy payloads of about 4 tons within a positioning accuracy of 2 mm under intense gamma radiation. To facilitate remote maintenance, blankets are segmented into 730 modules and rail-mounted vehicle remote maintenance was developed. According to the ITER R and D program, critical technology related to blanket maintenance was developed extensively through joint efforts of the Japan, EU, and U.S. home teams. This paper summarizes current blanket maintenance technology conducted by the Japan Home Team, including development of full-scale remote handling equipment and tools for blanket maintenance. (author)

Maintenance of nuclear power plants

International Nuclear Information System (INIS)

1982-01-01

This Guide covers the organizational and procedural aspects of maintenance but does not give detailed technical advice on the maintenance of particular plant items. It gives guidance on preventive and remedial measures necessary to ensure that all structures, systems and components important to safety are capable of performing as intended. The Guide covers the organizational and administrative requirements for establishing and implementing preventive maintenance schedules, repairing defective plant items, providing maintenance facilities and equipment, procuring stores and spare parts, selecting and training maintenance personnel, reviewing and controlling plant modifications arising from maintenance, and for generating, collecting and retaining maintenance records. Maintenance shall be subject to quality assurance in all aspects important to safety. Because quality assurance has been dealt with in detail in other Safety Guides, it is only included here in specific instances where emphasis is required. Maintenance is considered to include functional and performance testing of plant, surveillance and in-service inspection, where these are necessary either to support other maintenance activities or to ensure continuing capability of structures, systems and components important to safety to perform their intended functions

Practical considerations in developing an instrument-maintenance plan--

International Nuclear Information System (INIS)

Guth, M.A.S.

1989-01-01

The author develops a general set of considerations to explain how a consistent, well-organized, prioritized, and adequate time-allowance program plan for routine maintenance can be constructed. The analysis is supplemented with experience from the high flux isotope reactor (HFIR) at US Oak Ridge National Laboratory (ORNL). After the preventive maintenance (PM) problem was defined, the instruments on the schedule were selected based on the manufacturer's design specifications, quality-assurance requirements, prior classifications, experiences with the incidence of breakdowns or calibration, and dependencies among instruments. The effects of repair error in PM should be also studied. The HFIR requires three full-time technicians to perform both PM and unscheduled maintenance. A review is presented of concepts from queuing theory to determine anticipated breakdown patterns. In practice, the pneumatic instruments have a much longer lifetime than the electric/electronic instruments on various reactors at ORNL. Some special considerations and risk aversion in choosing a maintenance schedule

A predictive maintenance approach for improved nuclear plant availability

International Nuclear Information System (INIS)

Verma, R.M.P.; Pandya, M.B.; Kini, M.P.

1979-01-01

Predictive maintenance programme as against preventive maintenance programme aims at diagnosing, inspecting, monitoring, and objective condition-checking of equipment. It helps in forecasting failures, and scheduling the optimal frequencies for overhauls, replacements, lubrication etc. It also helps in establishing work load, manpower, resource planning and inventory control. Various stages of predictive maintenance programme for a nuclear power plant are outlined. A partial list of instruments for predictive maintenance is given. (M.G.B.)

Diagnostics of heavy mining equipment during the scheduled preventive maintenance

Science.gov (United States)

Drygin, M. Yu; Kuryshkin, N. P.

2018-01-01

Intensification of production, economic globalization and dramatic downgrade of the workers’ professional skills lead to unacceptable technical state of heavy mining equipment. Equipment maintenance outage reaches 84 % of the total downtime, of which emergency maintenance takes up to 36 % of time, that excesses 429 hours per year fr one excavator. It is shown that yearly diagnostics using methods of non-destructive check allows to reduce emergency downtime by 47 %, and 55 % of revealed defects can be eliminated without breaking the technological cycle of the equipment.

Total productive maintenance on example of automated foundry lines

Directory of Open Access Journals (Sweden)

S. Kukla

2009-07-01

Full Text Available Within framework of the presented study one has performed analysis of stoppages in automatic foundry lines operation, and basing on assumptions from complex maintenance system has undertaken himself to develop a service maintenance schedule for machinery installed in the line. Moreover, one has presented general assumptions of TPM system operated in conditions of series and multi-series production of cast iron castings. One has constructed operational database and has elaborated a list of line stoppage causes within a year. One has proposed a possibility of implementation of manufacturing systems modeling and simulating technique in management of production machinery operation in a foundry shop. Within framework of the simulation experiment one has developed schedules of production, schedules of maintenance and has forecasted indices of general productivity of the machinery for a various scenarios of events on example of casting line having in-series structure of operational reliability. In course of the study there was implemented ARENA universal software package to modeling and simulation of the manufacturing systems.

A framework to practical predictive maintenance modeling for multi-state systems

International Nuclear Information System (INIS)

Cher Ming Tan; Raghavan, Nagarajan

2008-01-01

A simple practical framework for predictive maintenance (PdM)-based scheduling of multi-state systems (MSS) is developed. The maintenance schedules are derived from a system-perspective using the failure times of the overall system as estimated from its performance degradation trends. The system analyzed in this work is a flow transmission water pipe system. The various factors influencing PdM-based scheduling are identified and their impact on the system reliability and performance are quantitatively studied. The estimated times to replacement of the MSS may also be derived from the developed model. The results of the model simulation demonstrate the significant impact of maintenance quality and the criteria for the call for maintenance (user demand) on the system reliability and mean performance characteristics. A slight improvement in maintenance quality is found to postpone the system replacement time by manifold. The consistency in the quality of maintenance work with minimal variance is also identified as a very important factor that enhances the system's future operational and downtime event predictability. The studies also reveal that in order to reduce the frequency of maintenance actions, it is necessary to lower the minimum user demand from the system if possible, ensuring at the same time that the system still performs its intended function effectively. The model proposed can be utilized to implement a PdM program in the industry with a few modifications to suit the individual industrial systems' needs

Management Tools for Bus Maintenance: Current Practices and New Methods. Final Report.

Science.gov (United States)

Foerster, James; And Others

Management of bus fleet maintenance requires systematic recordkeeping, management reporting, and work scheduling procedures. Tools for controlling and monitoring routine maintenance activities are in common use. These include defect and fluid consumption reports, work order systems, historical maintenance records, and performance and cost…

Evaluations of maintenance effectiveness on unavailability and risk

International Nuclear Information System (INIS)

Vesely, W.E.

1993-01-01

A methodology is presented for quantifying the effectiveness of maintenance on unavailability and on risk. The methodology is based on standard Markov modeling principles. What is new is the application to quantify maintenance effectiveness by explicitly quantifying maintenance benefits as well as maintenance's negative contributions. Maintenance effects are quantified by defining a degraded state for the component in addition to an operational state and a failed state which are usually defined. The maintenance model which is developed is a natural extension of the standard models used in reliability analysis and in Probabilistic Risk Assessments (PRAs). The results which are obtained can be directly used in PRAs. Applications of the methodology are presented by quantifying maintenance effectiveness on component performance and component unavailability for specific maintenance schedules

Planning of maintenance of electrical equipment in nuclear plants/laboratories [Paper No.: VB-3

International Nuclear Information System (INIS)

Narasinga Rao, S.N.; Bhattacharyya, A.K.

1981-01-01

Satisfactory operating performance of electrical systems ensures continuous availability of power to the various plants and machinery in nuclear plant and laboratories. For effective optimal functioning of the electrical equipment and to reduce their down time, scheduled planning of maintenance to the equipment is essential. Maintenance of power plant, nuclear or fossil, and industrial plant and research laboratories demands essential ingredients such as right type of trained and motivated technical personnel, adoption of standard procedures for maintenance, adequate safety and protection for equipment, safety procedures adopted in the installation to prevent hazards to the workers, provision of adequate stores and inventories, facilities for quick repairs and testing of equipment and effective planning of procedures for their maintenance. While breakdown maintenance allows equipment to operate before it is repaired or replaced, preventive maintenance makes use of scheduled inspection and periodical equipment overhaul and has little value for predicting future continuous performances of equipment. The engineered maintenance is most advantageous and offers maximum operating time to reduce down time of the equipment while adding predictive testing technique to aid in determining the frequency of overhaul of equipment. The important checks to be conducted and preventive maintenance programme to be scheduled are discussed in this paper. The safety and reliable functioning of the electrical equipment depend on proper optimal design, selection of equipment, their installation, subsequent maintenance and strict compliance with safety regulations. (author)

Development of divertor remote maintenance system

Energy Technology Data Exchange (ETDEWEB)

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

1998-04-01

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

Development of divertor remote maintenance system

International Nuclear Information System (INIS)

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

1998-01-01

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

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

International Nuclear Information System (INIS)

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

2003-01-01

tilting tables are 14 scheduled on-condition tasks, 10 scheduled on-restoration tasks, seven scheduled discard task. Whereas for 14 failure modes no scheduled maintenance has been proposed. Existing maintenance schedule for tilting tables indicates the maintenance action as and when required. Hence RCM based schedule specifies that additional preventive maintenance tasks need to be executed as compared to none initially. Cost incurred for this can be offset from the savings accrued from reduction in loss of production due to repetitive breakdowns. The methodology of RCM adopted in western industries cannot be applied as it is to Indian industries because of labour oriented nature, partially computerised information systems, non-availability of the information about cost of loss of production due to breakdown and age-reliability pattern of equipment, insufficient maintenance database. These problems can be overcome by development of sound MMIS, formulation of RCM review group and imparting suitable training to acquire the relevant skills in RCM. Thus RCM methodology can be applied to Indian industry for reduction of breakdowns as well as optimisation of preventive maintenance cost. This can further boost up the prospects of Indian industry to offer the products at globally competitive prices

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

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

Energy Technology Data Exchange (ETDEWEB)

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

1999-07-01

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

Darlington Station outage - a maintenance perspective

International Nuclear Information System (INIS)

Plourde, J.; Marczak, J.; Stone, M.; Myers, R.; Sutton, K.

1997-01-01

Ontario Hydro's Darlington Nuclear Generating Station (4x881MW(e)net) has carried out its first station outage since full commercial operation. The outage presented challenges to the organization in terms of outage planning, support, management, and safe execution within the constraints of schedule, budget and resources. This paper will focus on the success of the outage maintenance program, identifying the major work programs - a vacuum structure and containment outage, an emergency service water system outage, an emergency coolant injection system outage, intake channel inspections, low pressure service water inspections, and significant outage maintenance work on each of the four reactor units. Planning for the outage was initiated early in anticipation of this important milestone in the station's life. Detailed safety reviews - nuclear, radiation, and conventional - were conducted in support of the planned maintenance program. System lineup and work protection were provided by the Station Operator work group. Work protection permitry was initiated well in advance of the outage. Station maintenance staff resources were bolstered in support of the outage to ensure program execution could be maintained within the schedule. Training programs were in place to ensure that expectations were clear and that high standards would be maintained. Materials management issues in support of maintenance activities were given high priority to ensure no delays to the planned work. Station management review and monitoring in preparation for and during the outage ensured that staff priorities remained focused. Lessons learned from the outage execution are being formalized in maintenance procedures and outage management procedures, and shared with the nuclear community. (author)

Reliability centred maintenance of nuclear power plant facilities

International Nuclear Information System (INIS)

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

2011-01-01

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

Application of condition based maintenance to nuclear power plants

International Nuclear Information System (INIS)

Sonoda, Yukio; Nakano, Tomohito; Shimizu, Shunichi; Iida, Jun; Atomura, Masakazu; Abe, Masahiro

2002-01-01

Device Karte management system which supports application of condition based maintenance to nuclear power plants has been developed. The purpose of this system is to support maintenance personnel in device inspection scheduling based on operating condition monitoring and maintenance histories. There are four functions: field database, degradation estimation, inspection time decision and maintenance planning. The authors have been applying this system to dozens of devices of Onagawa Nuclear Power Station Unit No. 1 for one year. This paper represents the system concept and its application experiences. (author)

Components installation. Scheduling techniques applied at Framatome for the French nuclear program

International Nuclear Information System (INIS)

Cremese, G.

1982-09-01

The first scheduling objective is a timely delivery of heavy components manufactured by FRAMATOME factories: reactor vessel, steam generators and pressurizer. The second scheduling function is the preparation and updating of overall and detailed schedules for the coordination and follow-up of: design activities, progress at equipment suppliers, construction and erection activities of sub-contractors, test and start-up tasks by FRAMATOME and customer teams, and maintenance operations by FRAMATOME teams. I shall first describe the schedules for the contract first unit then show how the following units of the contract are scheduled in their turn

Shop Floor Scheduling for Program Depot Maintenance Considering Stochastic Repair Needs

National Research Council Canada - National Science Library

Gemmill, Douglas

2000-01-01

.... The research resulted in the development of a new method to identify the critical path within resource-constrained project scheduling problems, heuristic search methods that improved overall project...

A Real-Time Quantitative Condition Alerting and Analysis Support System for Aircraft Maintenance, Phase I

Data.gov (United States)

National Aeronautics and Space Administration — Financial constraints and the need for improved operational efficiency are requiring airlines to emphasize "on-condition" maintenance over scheduled maintenance...

Planning and control of maintenance systems modelling and analysis

CERN Document Server

Duffuaa, Salih O

2015-01-01

Analyzing maintenance as an integrated system with objectives, strategies and processes that need to be planned, designed, engineered, and controlled using statistical and optimization techniques, the theme of this book is the strategic holistic system approach for maintenance. This approach enables maintenance decision makers to view maintenance as a provider of a competitive edge not a necessary evil. Encompassing maintenance systems; maintenance strategic and capacity planning, planned and preventive maintenance, work measurements and standards, material (spares) control, maintenance operations and control, planning and scheduling, maintenance quality, training, and others, this book gives readers an understanding of the relevant methodology and how to apply it to real-world problems in industry. Each chapter includes a number exercises and is suitable as a textbook or a reference for a professionals and practitioners whilst being of interest to industrial engineering, mechanical engineering, electrical en...

Optimal preventive maintenance and repair policies for multi-state systems

International Nuclear Information System (INIS)

Sheu, Shey-Huei; Chang, Chin-Chih; Chen, Yen-Luan; George Zhang, Zhe

2015-01-01

This paper studies the optimal preventive maintenance (PM) policies for multi-state systems. The scheduled PMs can be either imperfect or perfect type. The improved effective age is utilized to model the effect of an imperfect PM. The system is considered as in a failure state (unacceptable state) once its performance level falls below a given customer demand level. If the system fails before a scheduled PM, it is repaired and becomes operational again. We consider three types of major, minimal, and imperfect repair actions, respectively. The deterioration of the system is assumed to follow a non-homogeneous continuous time Markov process (NHCTMP) with finite state space. A recursive approach is proposed to efficiently compute the time-dependent distribution of the multi-state system. For each repair type, we find the optimal PM schedule that minimizes the average cost rate. The main implication of our results is that in determining the optimal scheduled PM, choosing the right repair type will significantly improve the efficiency of the system maintenance. Thus PM and repair decisions must be made jointly to achieve the best performance

Stress-reducing preventive maintenance model for a unit under stressful environment

International Nuclear Information System (INIS)

Park, J.H.; Chang, Woojin; Lie, C.H.

2012-01-01

We develop a preventive maintenance (PM) model for a unit operated under stressful environment. The PM model in this paper consists of a failure rate model and two cost models to determine the optimal PM scheduling which minimizes a cost rate. The assumption for the proposed model is that stressful environment accelerates the failure of the unit and periodic maintenances reduce stress from outside. The failure rate model handles the maintenance effect of PM using improvement and stress factors. The cost models are categorized into two failure recognition cases: immediate failure recognition and periodic failure detection. The optimal PM scheduling is obtained by considering the trade-off between the related cost and the lifetime of a unit in our model setting. The practical usage of our proposed model is tested through a numerical example.

Task-specific shell for scheduling problems, ARES[sub TM]/SCH. Scheduling mondai muke task tokka shell ARES[sub TM]/SCH

Energy Technology Data Exchange (ETDEWEB)

Kojima, S; Narimatsu, K [Toshiba Corp., Tokyo (Japan)

1994-08-01

An Expert System (ES) Shell (developed by Toshiba Corp.) which applies to the scheduling of production plan and operation plan is introduced. It describes that this tool is equipped with flowchart editor and constraint condition editor which mention the knowledge related to scheduling method, and that the former expresses scheduling procedure knowledge in the form of flowchart by combining basic tasks prepared beforehand, and the latter expresses constraint conditions which should be satisfied by the schedule, and knowledge related to the priority order which should be considered in-between in the form of IF-THEN Rule which is very close to Japanese. In addition, the knowledge is equipped with knowledge debugging system which conducts debugging while executing the knowledge. It adds that by using this tool, the manhour required for the development and maintenance of ES can be reduced considerably. 2 refs., 3 figs.

Operation and maintenance support expert systems for BWR nuclear power plants

International Nuclear Information System (INIS)

Miyazawa, Tatsuo; Hayakawa, Hiroyasu; Fukutomi, Shigeki

1990-01-01

Toshiba has been developing expert systems for operation and maintenance support in BWRs. These expert systems are designed to be integrated with conventional plant monitoring systems, and maintenance management systems to provide both comprehensive and powerful support capabilities. Some of these expert systems are already being used on a trial basis both within Toshiba and in electric power utility companies. This paper describes expert systems for the support of plant and equipment monitoring, maintenance scheduling, and maintenance work procedure planning. (author)

The Preventive Signaling Maintenance Crew Scheduling Problem for European Railway Traffic Management system (ERTMS)

DEFF Research Database (Denmark)

M. Pour, Shahrzad; Stidsen, Thomas Jacob Riis; Rasmussen, Kourosh Marjani

, the western part of Denmark. This case is particularly interesting, since the entire railway signalling system is currently being upgraded to the new European Railway Traffic Management System (ERTMS) standard. The new signals need continuous maintenance and in this article we plan the distribution of crew......A railway system is a large and complex infrastructure, which requires continuous maintenance in order to function correctly. Proper maintenance is critical but can also be costly. In this paper we consider the practical case of planning the preventive maintenance of railway signals in Jutland...

Efficient Workplan Management in Maintenance Tasks

NARCIS (Netherlands)

Wilson, M.; Roos, N.; Huisman, B.; Witteveen, C.

2011-01-01

NedTrain is a Dutch company tasked with performing the maintenance of the rolling stock of the national railway company, NS. NedTrain owns several workshops at different locations. The scheduling in one such workshop will be taken as point of departure for the discussion in this paper. After

Good practices for cost effective maintenance of nuclear power plants

International Nuclear Information System (INIS)

1997-02-01

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

Coordinated preventive maintenance scheduling of GENCO and TRANSCO in restructured power systems

International Nuclear Information System (INIS)

Geetha, T.; Swarup, K. Shanti

2009-01-01

Preventive maintenance of generating units and lines, in a competitive electric energy environment is proposed. Inclusion of transmission constraints and forced outage rates, over a specified operational period is considered. For generator maintenance the objective of the ISO is to maintain adequate level of reliability throughout the operational period, for which Bender's decomposition technique is used. The objective of the GENCO is to maximize profit or to minimize loss in profit, for which transmission constrained price based unit commitment (TCPBUC), based on Lagrangian relaxation method is used. Bender's decomposition technique is used for line maintenance, with adequate level of reliability. A coordinating technique using penalty factors is incorporated to obtain convergence of the conflicting objectives. The transmission constraints are modeled using dc sensitivity factors. Detailed case studies of six-bus systems and IEEE RTS system are presented and discussed. (author)

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

International Nuclear Information System (INIS)

Von Hatten, P.

2008-01-01

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

Maintenance of the Hanford cone penetrometer platform during fiscal year 1999

International Nuclear Information System (INIS)

IWATATE, D.F.

1998-01-01

This SOW describes services requested of Applied Research and Associates, Inc. (ARA), as a commercial provider of cone penetrometer equipment and services, to provide routine inspection and minimum preventive maintenance on the Hanford CP Platform (CPP) during Fiscal Year 1999. This SOW specifically pertains to the maintenance of the CPP and associated support equipment and is limited in scope to routine preventive maintenance and identification of any deficiencies. ARA is the original manufacturer of the CPP and will conduct this work following the vendor-prepared maintenance schedule

46 CFR 109.301 - Operational readiness, maintenance, and inspection of lifesaving equipment.

Science.gov (United States)

2010-10-01

... and cleaning each fuel tank, and refilling it with fresh fuel. (2) Each davit, winch, fall and other...(e); (ii) Maintenance and repair instructions; (iii) A schedule of periodic maintenance; (iv) A... repair equipment. Spare parts and repair equipment must be provided for each lifesaving appliance and...

Maintenance implementation plan for the Plutonium Finishing Plant. Revision 3

International Nuclear Information System (INIS)

Meldrom, C.A.

1996-03-01

This document outlines the Maintenance Implementation Plan (MIP) for the Plutonium Finishing Plant (PFP) located at the Hanford site at Richland, Washington. This MIP describes the PFP maintenance program relative to DOE order 4330.4B. The MIP defines the key actions needed to meet the guidelines of the Order to produce a cost-effective and efficient maintenance program. A previous report identified the presence of significant quantities of Pu-bearing materials within PFP that pose risks to workers. PFP's current mission is to develop, install and operate processes which will mitigate these risks. The PFP Maintenance strategy is to equip the facility with systems and equipment able to sustain scheduled PFP operations. The current operating run is scheduled to last seven years. Activities following the stabilization operation will involve an Environmental Impact Statement (EIS) to determine future plant activities. This strategy includes long-term maintenance of the facility for safe occupancy and material storage. The PFP maintenance staff used the graded approach to dictate the priorities of the improvement and upgrade actions identified in Chapter 2 of this document. The MIP documents PFP compliance to the DOE 4330.4B Order. Chapter 2 of the MIP follows the format of the Order in addressing the eighteen elements. As this revision is a total rewrite, no sidebars are included to highlight changes

RCM optimization of a system under both preventive and corrective maintenance

International Nuclear Information System (INIS)

Bris, R.; Cepin, M.

2005-01-01

Testing and maintenance activities of power electrical equipment are an important potential for both risk and cost reduction. A multi-objective maintenance optimization method is presented based on the Genetic Algorithms (GA) technique. The method determines the optimal schedule of preventive maintenance actions based on minimization both selected risk measure and cost. Applied cost model takes into account both preventive and corrective maintenance. This paper also presents application of the methodology to optimize maintenance of a real distribution network 22 kV. Conclusions and recommendations for practice are made on the basis of obtained results. (author)

On-line maintenance PSA support at NPP Krsko

International Nuclear Information System (INIS)

Prosen, R.; Vrbanic, I.; Kastelan, M.

2000-01-01

In 1997 Krsko NPP initiated the on-line maintenance (OLM) practice. On-line maintenance constitutes of corrective activities, preventive activities, surveillance activities, tests and inspections, as well as calibrations and modifications, taking place during the normal power operations. The on-line maintenance is a multidisciplinary process consisting of activity specification, planning, and preparation and performing of the OLM activity of interest. The primary role of the PSA group is to assess from the r isk perspective , using the plant-specific NEK PSA model, system unavailability and the impact to the plant operational risk. The intent is to support planning of the on-line maintenance activities from the risk perspective. The risk evaluation of the OLM activities is based on the probability of core damage evaluation for the defined discrete plant configuration states, determined by the OLM activities. Within this application, the optimized, plant-specific PSA model is used on Risk Spectrum platform. To perform the risk assessment of the on-line maintenance activities, first the systems to be affected are defined based on the planned OLM activities. The next important step is the assessment of the planned work schedule. To define the final schedule, the co-ordination and optimizing the planned OLM activities needs activation of all participating departments, supported also from PSA group. The P3 (i.e. Primavera) planning tool system windows are defined for different systems and groups of systems, and the activities are sorted in particular weeks according to these windows. (author)

Electric motor predictive and preventive maintenance guide

International Nuclear Information System (INIS)

Oliver, J.A.

1992-07-01

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

Staffing, overtime, and shift scheduling project

International Nuclear Information System (INIS)

Lewis, P.M.

1989-01-01

Recent events at the Peach Bottom nuclear power plant have demonstrated the need to establish a quantifiable basis for assessing the safety significance of long work hours on nuclear power plant operators. The incidents at TMI-2, Chernobyl, and Bhopal, which all occurred during the late evening/night shift, further highlight the importance of the relationship between shift scheduling and performance. The objective of this project is to estimate, using statistical analysis on data from the nuclear industry, the effects on safety of staffing levels, overtime, and shift scheduling for operators and maintenance personnel. Regarding staffing levels, the Nuclear Regulatory Commission (NRC) currently has no explicit regulation concerning the minimum acceptable levels of staffing in a plant that has an operating license. The NRC has no systematic method for collecting data on the number of licensed operators on the operating crews. In 1982 the NRC recommended that plants write into their technical specifications a model policy on overtime. Currently, 77 nuclear power plant units have the model policy or a modification of it written into their technical specifications; 33 units have no policy on overtime. The model policy sets limits on overtime for safety related personnel, although these limits can be exceeded with plant manger approval. The US nuclear power industry has three types of shift schedules: (1) forward-rotating 8-hour/day shift schedules, (2) backward-rotating 8-hour/day schedules, and (3) 12-hour/day schedules

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

340 Facility maintenance implementation plan

International Nuclear Information System (INIS)

1995-03-01

This Maintenance Implementation Plan (MIP) has been developed for maintenance functions associated with the 340 Facility. This plan is developed from the guidelines presented by Department of Energy (DOE) Order 4330.4B, Maintenance Management Program (DOE 1994), Chapter II. The objective of this plan is to provide baseline information for establishing and identifying Westinghouse Hanford Company (WHC) conformance programs and policies applicable to implementation of DOE order 4330.4B guidelines. In addition, this maintenance plan identifies the actions necessary to develop a cost-effective and efficient maintenance program at the 340 Facility. Primary responsibility for the performance and oversight of maintenance activities at the 340 Facility resides with Westinghouse Hanford Company (WHC). Maintenance at the 340 Facility is performed by ICF-Kaiser Hanford (ICF-KH) South Programmatic Services crafts persons. This 340 Facility MIP provides interface requirements and responsibilities as they apply specifically to the 340 Facility. This document provides an implementation schedule which has been developed for items considered to be deficient or in need of improvement. The discussion sections, as applied to implementation at the 340 Facility, have been developed from a review of programs and practices utilizing the graded approach. Biennial review and additional reviews are conducted as significant programmatic and mission changes are made. This document is revised as necessary to maintain compliance with DOE requirements

340 Facility maintenance implementation plan

Energy Technology Data Exchange (ETDEWEB)

NONE

1995-03-01

This Maintenance Implementation Plan (MIP) has been developed for maintenance functions associated with the 340 Facility. This plan is developed from the guidelines presented by Department of Energy (DOE) Order 4330.4B, Maintenance Management Program (DOE 1994), Chapter II. The objective of this plan is to provide baseline information for establishing and identifying Westinghouse Hanford Company (WHC) conformance programs and policies applicable to implementation of DOE order 4330.4B guidelines. In addition, this maintenance plan identifies the actions necessary to develop a cost-effective and efficient maintenance program at the 340 Facility. Primary responsibility for the performance and oversight of maintenance activities at the 340 Facility resides with Westinghouse Hanford Company (WHC). Maintenance at the 340 Facility is performed by ICF-Kaiser Hanford (ICF-KH) South Programmatic Services crafts persons. This 340 Facility MIP provides interface requirements and responsibilities as they apply specifically to the 340 Facility. This document provides an implementation schedule which has been developed for items considered to be deficient or in need of improvement. The discussion sections, as applied to implementation at the 340 Facility, have been developed from a review of programs and practices utilizing the graded approach. Biennial review and additional reviews are conducted as significant programmatic and mission changes are made. This document is revised as necessary to maintain compliance with DOE requirements.

EFFICIENT MULTI-OBJECTIVE EVOLUTIONARY ALGORITHM FOR JOB SHOP SCHEDULING

Institute of Scientific and Technical Information of China (English)

Lei Deming; Wu Zhiming

2005-01-01

A new representation method is first presented based on priority rules. According to this method, each entry in the chromosome indicates that in the procedure of the Giffler and Thompson (GT) algorithm, the conflict occurring in the corresponding machine is resolved by the corresponding priority rule. Then crowding-measure multi-objective evolutionary algorithm (CMOEA) is designed,in which both archive maintenance and fitness assignment use crowding measure. Finally the comparisons between CMOEA and SPEA in solving 15 scheduling problems demonstrate that CMOEA is suitable to job shop scheduling.

Preventive and corrective maintenance for MINT EPS 3000 electron beam machine

International Nuclear Information System (INIS)

Siti Aiasah Hashim; Shaari Jahar

2005-01-01

Preventive and corrective maintenance of a high energy electron is to ensure that the machine would not fail during operation. MINT's EPS 3000 electron beam machine has been in operation for almost 12 years. Throughout those years, events relating to scheduled overhauls and unscheduled corrective maintenance had provided invaluable experience in the form of informal maintenance training to the operators. With the implementation of ISO 9001:2000 Quality Management System at the facility, the preventive and corrective maintenance program is becoming more structured and orderly. Collected maintenance data shall be used to initiate continual improvement activities in the facility.This paper describes MINT-ALURTRON's 12 years experience in providing maintenance work for the EPS 3000. (Author)

Development of the tool infrastructure for implementation of the maintenance rule

International Nuclear Information System (INIS)

Lo, Chung-Kung; Hsu, Pi-Lin

2009-01-01

INER PSA Group helps the three operating plants in Taiwan to decide the importance of their scoped-in equipment in terms of risk significance and develop the application database software (MEMOS) to implement the maintenance effectiveness monitoring process. NER also develops a software tool (MIRU) used in the on-line maintenance scheduling and risk assessment process. It serves as a platform for the plants to plan their daily maintenance activities and perform the risk assessment in the future rolling on-line maintenance. The implementation of routine on-line maintenance will be a critical step towards improving the capacity factors and thus further enhancement of the performance of nuclear power in Taiwan

Measurement and control system for ITER remote maintenance equipment

Energy Technology Data Exchange (ETDEWEB)

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

1998-04-01

ITER in-vessel components such as blankets and divertors are categorized as scheduled maintenance components because they are subjected to severe plasma heat and particle loads. Blanket maintenance requires remote handling equipment and tools able to handle Heavy payloads of about 4 tons within a 2 mm precision tolerance. Divertor maintenance requires remote replacement of 60 cassettes with a dead weight of about 25 tons each. In the ITER R and D program, full-scale remote handling equipment for blanket and divertor maintenance has been designed and assembled for demonstration tests. This paper reviews the measurement and control system developed for full-scale remote handling equipment, the Japan Home Team contribution. (author)

Measurement and control system for ITER remote maintenance equipment

International Nuclear Information System (INIS)

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

1998-01-01

ITER in-vessel components such as blankets and divertors are categorized as scheduled maintenance components because they are subjected to severe plasma heat and particle loads. Blanket maintenance requires remote handling equipment and tools able to handle Heavy payloads of about 4 tons within a 2 mm precision tolerance. Divertor maintenance requires remote replacement of 60 cassettes with a dead weight of about 25 tons each. In the ITER R and D program, full-scale remote handling equipment for blanket and divertor maintenance has been designed and assembled for demonstration tests. This paper reviews the measurement and control system developed for full-scale remote handling equipment, the Japan Home Team contribution. (author)

40 CFR 63.7826 - How do I demonstrate initial compliance with the operation and maintenance requirements that...

Science.gov (United States)

2010-07-01

... preventative maintenance schedule and, as applicable, detailed descriptions of the corrective action procedures... compliance with the operation and maintenance requirements that apply to me? 63.7826 Section 63.7826... Compliance Requirements § 63.7826 How do I demonstrate initial compliance with the operation and maintenance...

Optimisation of distributed maintenance: Modelling and application to the multi-factory production

Energy Technology Data Exchange (ETDEWEB)

Simeu-Abazi, Zineb, E-mail: Zineb.Simeu-Abazi@g-scop.inpg.fr [Laboratory G-SCOP, 46 Avenue Felix Viallet, 38031 Grenoble Cedex 1 (France); Ahmad, Alali Alhouaij [Laboratory G-SCOP, 46 Avenue Felix Viallet, 38031 Grenoble Cedex 1 (France)

2011-11-15

This paper concerns the modelling and the cost evaluation of maintenance activities in a distributed context. In this work we study the particular case where the maintenance activities are executed by two workshops: a central maintenance workshop (CMW) and a mobile maintenance workshop (MMW). The CMW concerns the repairing process for the corrective maintenance and the MMW executes all preventive maintenance in several factories according to a defined scheduling. The aim is to take into account the resources (spare parts in the MMW) and maintenance actions for a given operating budget. A modular approach for modelling a multi-site structure is proposed to achieve the aim of improving the availability of facilities on production sites while minimising the cost of maintenance.

Analysis of the ITER ECH Upper Port Launcher remote maintenance using virtual reality

NARCIS (Netherlands)

Elzendoorn, B.; Baar, M. de; Chavan, R.; Goodman, T.; Heemskerk, C.; Heidinger, R.; Kleefeldt, K.; Koning, J.; Sanders, S.; Späh, P.; Strauss, D.; Verhoeven, T.; Vreede, F. de

2009-01-01

All ITER sub-systems of remote handling (RH) classes 1 and 2 have to be remotely maintainable. The maintenance strategy for these components has to ensure system availability after failure or scheduled maintenance. This paper shows how virtual reality (VR) simulation [1] can be used as a tool to

SUMO: operation and maintenance management web tool for astronomical observatories

Science.gov (United States)

Mujica-Alvarez, Emma; Pérez-Calpena, Ana; García-Vargas, María. Luisa

2014-08-01

SUMO is an Operation and Maintenance Management web tool, which allows managing the operation and maintenance activities and resources required for the exploitation of a complex facility. SUMO main capabilities are: information repository, assets and stock control, tasks scheduler, executed tasks archive, configuration and anomalies control and notification and users management. The information needed to operate and maintain the system must be initially stored at the tool database. SUMO shall automatically schedule the periodical tasks and facilitates the searching and programming of the non-periodical tasks. Tasks planning can be visualized in different formats and dynamically edited to be adjusted to the available resources, anomalies, dates and other constrains that can arise during daily operation. SUMO shall provide warnings to the users notifying potential conflicts related to the required personal availability or the spare stock for the scheduled tasks. To conclude, SUMO has been designed as a tool to help during the operation management of a scientific facility, and in particular an astronomical observatory. This is done by controlling all operating parameters: personal, assets, spare and supply stocks, tasks and time constrains.

Operations and maintenance plans for the TFTR

International Nuclear Information System (INIS)

Allen, H.L.; Fedor, B.J.

1978-01-01

Princeton University Plasma Physics Laboratory (PPPL) is constructing a Tokamak Fusion Test Reactor (TFTR) scheduled to begin operation for fusion research experiments in late 1981, first with hydrogen and deuterium plasmas and later, in the second phase, using tritium for high power fusion studies. This latter mode will introduce considerable complexity to operation and maintenance of the TFTR in terms of meeting requirements for tritium handling, adequate radiation shielding, and corrective and preventive maintenance procedures. In this paper we discuss plans for the installation and preoperational testing of the major subsystems of TFTR, proposed start-up and operating scenarios for the device and the system of operational control. In addition, the TFTR Maintenance Plan and related procedures for specific major maintenance tasks are described, including the use of remote handling equipment and remote manipulators. Each of these topics is addressed in terms of the current status of planning and development

Optimization of the scheduled maintenance on the power units of the nuclear power plants with WWER

International Nuclear Information System (INIS)

Skalozubov, V.I.; Kovrizhkin, Yu.L.; Kolykhanov, V.N.; Kochneva, V.Yu.; Urbanskij, V.V.

2008-01-01

The advanced international and domestic experience in the field of the maintenance optimization of the power units of NPPs, as well, as on the base of the planning optimization, the maintenance organization and carrying out, the technical maintenance and repair control system automatization, the testing and monitoring optimization during the service process, the modernization of the technology and technical tools of the maintenance service and control is represented

Installation, operation, and maintenance for the pyramidal optics solar system installed at Yacht Cover, Columbia, South Carolina

Science.gov (United States)

1980-09-01

Information concerning the installation, operation, and maintenance of the pyramidal Solar System for space heating and domestic hot water is presented. Principles of operation, sequence of installation, and procedures for the operation and maintenance of each subsystem making up the solar system are presented. Troubleshooting charts and maintenance schedules are presented.

Configuration management of on-line maintenance

International Nuclear Information System (INIS)

Grantom, C.R.

1996-01-01

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

A preventive maintenance model for leased equipment subject to internal degradation and external shock damage

International Nuclear Information System (INIS)

Zhou, Xiaojun; Wu, Changjie; Li, Yanting; Xi, Lifeng

2016-01-01

A periodic preventive maintenance modeling method is proposed for leased equipment with continuous internal degradation and stochastic external shock damage considered simultaneously, which can facilitate the equipment lessor to optimize the maintenance schedule for the same kind of equipment rented by different lessees. A novel interactive mechanism between the continuous internal degradation and the stochastic external shock damage is established on the hazard rate of the equipment with integrating the imperfect effect of maintenance. Two improvement factors are defined for the modeling of imperfect maintenance. The number of failures resulting from internal degradation and from external shocks are both mathematically deduced based on this interactive mechanism. The optimal preventive maintenance scheme is obtained by minimizing the cumulative maintenance cost throughout the lease period. Numerical example shows that the proposed preventive maintenance model not only can reflect the reliability status of the equipment but also can clearly distinguish between the impact from internal degradation and that from external shocks. - Highlights: • We propose an imperfect periodic preventive maintenance model for leased equipment. • It can distinguish between the impact from internal degradation and that from external shocks. • An internal–external interactive mechanism is proposed. • Two improvement factors are introduced into the modeling of imperfect maintenance. • The model is helpful for the PM scheduling of the same equipment rented by different lessees.

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

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

Three AREVA tools for maintenance and outage support

International Nuclear Information System (INIS)

Lumpe, A.

2012-01-01

WlS is a knowledge-based database for the support of nuclear maintenance for components of different types It is productive since 2004 and has been continuously developed according to customer requirements. WIS allows for a centralized management of maintenance information and knowledge, including strategies, scheduling and reporting. WIS is already utilized in national and international NPPs. lts main advantages are: Support of service documentation for plant and service company employees, Support of integration into already existing IT infrastructure, Support of information and knowledge sharing, Easy and intuitive information usage, Savings by using standardized approach.

Field maintenance of radiation-shielding windows at HFEF

International Nuclear Information System (INIS)

Tobias, D.A.

1983-01-01

The achievement of excellent viewing through hot-cell shielding windows does not occur by chance. Instead, it requires a well planned and executed program of field maintenance. The lack of such a program is a major factor when a hot-cell facility has poor window viewing. At HFEF, all preventive maintenance is performed by one group of trained technical-support personnel under the immediate direction of a Systems Engineer, who has responsibility for the shielding windows. Window maintenance is prescheduled and recorded by being incorporated into the computerized Maintenance Data System (MDS). Measurements of window light transmission are scheduled annually to determine glass browning or oil cloudiness conditions within the window tank. The tank oil is sampled and chemically analyzed annually to determine the moisture content, the acidity, and the probable deterioration rate caused by irradiation

A General State-Space Formulation for Online Scheduling

Directory of Open Access Journals (Sweden)

Dhruv Gupta

2017-11-01

Full Text Available We present a generalized state-space model formulation particularly motivated by an online scheduling perspective, which allows modeling (1 task-delays and unit breakdowns; (2 fractional delays and unit downtimes, when using discrete-time grid; (3 variable batch-sizes; (4 robust scheduling through the use of conservative yield estimates and processing times; (5 feedback on task-yield estimates before the task finishes; (6 task termination during its execution; (7 post-production storage of material in unit; and (8 unit capacity degradation and maintenance. Through these proposed generalizations, we enable a natural way to handle routinely encountered disturbances and a rich set of corresponding counter-decisions. Thereby, greatly simplifying and extending the possible application of mathematical programming based online scheduling solutions to diverse application settings. Finally, we demonstrate the effectiveness of this model on a case study from the field of bio-manufacturing.

Optimizing Maintenance Planning in the Production Industry Using the Markovian Approach

Directory of Open Access Journals (Sweden)

B Kareem

2012-12-01

Full Text Available Maintenance is an essential activity in every manufacturing establishment, as manufacturing effectiveness counts on the functionality of production equipment and machinery in terms of their productivity and operational life. Maintenance cost minimization can be achieved by adopting an appropriate maintenance planning policy. This paper applies the Markovian approach to maintenance planning decision, thereby generating optimal maintenance policy from the identified alternatives over a specified period of time. Markov chains, transition matrices, decision processes, and dynamic programming models were formulated for the decision problem related to maintenance operations of a cable production company. Preventive and corrective maintenance data based on workloads and costs, were collected from the company and utilized in this study. The result showed variability in the choice of optimal maintenance policy that was adopted in the case study. Post optimality analysis of the process buttressed the claim. The proposed approach is promising for solving the maintenance scheduling decision problems of the company.

LHC Report: The machine under maintenance

CERN Multimedia

Katy Foraz for the LHC Team

2012-01-01

The LHC Christmas break started on 12 December. Since then, teams have been working hard to complete all the maintenance work planned to ensure the reliable operation of the LHC in 2012.   Installation of shielding at Point 1. The maintenance work is being carried out on key infrastructure such as the cooling, ventilation, electricity and safety systems. Maintenance work is being carried out not just in the LHC but also across the whole accelerator complex, which makes planning the work even more complicated. At the time of going to print, 50% of the cryogenics system maintenance has been finished, which, according to the schedule, will allow the LHC teams to start cooling down the first sectors next week to have the entire machine cold by the end of February. A lot of activity is going on in order to mitigate the effects of radiation on equipment installed in the LHC tunnel and underground areas during 2012 operation. To this end, teams have installed additional shielding at Point 1 (see ph...

Integrating the sequence dependent setup time open shop problem and preventive maintenance policies

Directory of Open Access Journals (Sweden)

K. Naboureh

2016-09-01

Full Text Available In most industrial environments, it is usually considered that machines are accessible throughout the planning horizon, but in real situation, machines may be unavailable due to a scheduled preventive maintenance where the periods of unavailability are known in advance. The main idea of this paper is to consider different preventive maintenance policies on machines regarding open shop scheduling problem (OSSP with sequence dependent setup times (SDST using immune algorithm. The preventive maintenance (PM policies are planned for maximizing availability of machines or keeping minimum level of reliability through the production horizon. The objective function of the paper is to minimize makespan. In total, the proposed algorithm extensively is compared with six adaptations of existing heuristic and meta-heuristic methods for the problem through data sets from benchmarks based on Taillard’s instances with some adjustments. The results show that the proposed algorithm outperforms other algorithms for this problem.

A dynamic predictive maintenance policy for complex multi-component systems

International Nuclear Information System (INIS)

Van Horenbeek, Adriaan; Pintelon, Liliane

2013-01-01

The use of prognostic methods in maintenance in order to predict remaining useful life is receiving more attention over the past years. The use of these techniques in maintenance decision making and optimization in multi-component systems is however a still underexplored area. The objective of this paper is to optimally plan maintenance for a multi-component system based on prognostic/predictive information while considering different component dependencies (i.e. economic, structural and stochastic dependence). Consequently, this paper presents a dynamic predictive maintenance policy for multi-component systems that minimizes the long-term mean maintenance cost per unit time. The proposed maintenance policy is a dynamic method as the maintenance schedule is updated when new information on the degradation and remaining useful life of components becomes available. The performance, regarding the objective of minimal long-term mean cost per unit time, of the developed dynamic predictive maintenance policy is compared to five other conventional maintenance policies, these are: block-based maintenance, age-based maintenance, age-based maintenance with grouping, inspection condition-based maintenance and continuous condition-based maintenance. The ability of the predictive maintenance policy to react to changing component deterioration and dependencies within a multi-component system is quantified and the results show significant cost savings

Maintenance optimization in nuclear power plants through genetic algorithms

International Nuclear Information System (INIS)

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

1999-01-01

Establishing suitable scheduled maintenance tasks leads to optimizing the reliability of nuclear power plant safety systems. The articles addresses this subject, whilst endeavoring to tackle an overall optimization process for component availability and safety systems through the use of genetic algorithms. (Author) 20 refs

Risk-based Operation and Maintenance for Offshore Wind Turbines

DEFF Research Database (Denmark)

Sørensen, John Dalsgaard; Nielsen, Jannie Jessen

2011-01-01

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...... statistics and costs of the different operations. The different OM strategies are described and compared in an illustrative example with focus on which types of information that are needed. Special focus is on comparison between risk-based maintenance strategies and the conventional maintenance planning...... 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...

Remote operation and automation of the maintenance works under the radiation field

Energy Technology Data Exchange (ETDEWEB)

Asai, T; Koga, A; Shirasu, I; Miida, T

1983-06-01

More than ninety per cent of the personnel radiation exposure at the nuclear power station is attributable to the maintenance works during the plant shutdown. The maintenance robots have effectively contributed in reducing the annual inspection and refueling schedule and the personnel radiation exposure. Future prospects of robotics depend on the grade of development in robot technology and plant engineering itself to accommodate such robot tools, since plant facilities and maintenance procedure today is difficult to replace with machines due to their diversified and complex nature.

Remote operation and automation of the maintenance works under the radiation field

Energy Technology Data Exchange (ETDEWEB)

Asai, Takashi; Koga, Akihiko; Shirasu, Isao; Miida, Toshiro [Mitsubishi Heavy Industries Ltd., Tokyo (Japan)

1983-08-01

More than ninety per cent of the personnel radiation exposure at the nuclear power station is attributable to the maintenence works during the plant shutdown. The maintenance robots have effectively contributed in reducing the annual inspection and refueling schedule and the personnel radiation exposure. Future prospects of robotics depend on the grade of development in robot technology and plant engineering itself to accommodate such robot tools, since plant facilities and maintenance procedure today are so difficult to replace with machines due to their deversified and complexed nature.

Remote operation and automation of the maintenance works under the radiation field

Energy Technology Data Exchange (ETDEWEB)

Asai, Takashi; Koga, Akihiko; Shirasu, Isao; Miida, Toshiro [Mitsubishi Heavy Industries Ltd., Tokyo (Japan)

1983-01-01

More than ninety per cent of the personnel radiation exposure at the nuclear power station is attributable to the maintenance works during the plant shutdown. The maintenance robots have effectively contributed in reducing the annual inspection and refueling schedule and the personnel radiation exposure. Future prospects of robotics depend on the grade of development in robot technology and plant engineering itself to accommodate such robot tools, since plant facilities and maintenance procedure today is so defficult to replace with machines due to their diversified and complexed nature.

The applicability of knowledge-based scheduling to the utilities industry

International Nuclear Information System (INIS)

Yoshimoto, G.; Gargan, R. Jr.; Duggan, P.

1992-01-01

The Electric Power Research Institute (EPRI), Nuclear Power Division, has identified the three major goals of high technology applications for nuclear power plants. These goals are to enhance power production through increasing power generation efficiency, to increase productivity of the operations, and to reduce the threats to the safety of the plant. Our project responds to the second goal by demonstrating that significant productivity increases can be achieved for outage maintenance operations based on existing knowledge-based scheduling technology. Its use can also mitigate threats to potential safety problems by means of the integration of risk assessment features into the scheduler. The scheduling approach uses advanced techniques enabling the automation of the routine scheduling decision process that previously was handled by people. The process of removing conflicts in scheduling is automated. This is achieved by providing activity representations that allow schedulers to express a variety of different scheduling constraints and by implementing scheduling mechanisms that simulate kinds of processes that humans use to find better solutions from a large number of possible solutions. This approach allows schedulers to express detailed constraints between activities and other activities, resources (material and personnel), and requirements that certain states exist for their execution. Our scheduler has already demonstrated its benefit to improving the shuttle processing flow management at Kennedy Space Center. Knowledge-based scheduling techniques should be examined by utilities industry researchers, developers, operators and management for application to utilities planning problems because of its great cost benefit potential. 4 refs., 4 figs

Remote operation and automation of the maintenance works under the radiation field

International Nuclear Information System (INIS)

Asai, Takashi; Koga, Akihiko; Shirasu, Isao; Miida, Toshiro

1983-01-01

More than ninety per cent of the personnel radiation exposure at the nuclear power station is attributable to the maintenence works during the plant shutdown. The maintenance robots have effectively contributed in reducing the annual inspection and refueling schedule and the personnel radiation exposure. Future prospects of robotics depend on the grade of development in robot technology and plant engineering itself to accommodate such robot tools, since plant facilities and maintenance procedure today is so difficult to replace with machines due to their deversified and complexed nature. (author)

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

DEFF Research Database (Denmark)

Ambühl, Simon; Sørensen, John Dalsgaard

2017-01-01

Inspection and maintenance expenses cover a considerable part of the cost of energy from offshore wind turbines. Risk-based maintenance planning approaches are a powerful tool to optimize maintenance and inspection actions and decrease the total maintenance expenses. Risk-based planning is based...... on many input parameters, which are in reality often not completely known. This paper will assess the cost impact of this incomplete knowledge based on a case study following risk-based maintenance planning. The sensitivity study focuses on weather forecast uncertainties, incomplete knowledge about...... the needed repair time on the site as well as uncertainties about the operational range of the boat and helicopter used to access the broken wind turbine. The cost saving potential is estimated by running Crude Monte Carlo simulations. Furthermore, corrective and preventive (scheduled and condition...

Value centric approaches to the design, operations and maintenance of wind turbines

Science.gov (United States)

Khadabadi, Madhur Aravind

Wind turbine maintenance is emerging as an unexpectedly high component of turbine operating cost, and there is an increasing interest in managing this cost. This thesis presents an alternative view of maintenance as a value-driver, and develops an optimization algorithm to evaluate the value delivered by different maintenance techniques. I view maintenance as an operation that moves the turbine to an improved state in which it can generate more power and, thus, earn more revenue. To implement this approach, I model the stochastic deterioration of the turbine in two dimensions: the deterioration rate, and the extent of deterioration, and then use maintenance to improve the state of the turbine. The value of the turbine is the difference between the revenue from to the power generation and the costs incurred in operation and maintenance. With a focus on blade deterioration, I evaluate the value delivered by implementing two different maintenance schemes, predictive maintenance and scheduled maintenance. An example of predictive maintenance technique is the use of Condition Monitoring Systems to precisely detect deterioration. I model Condition Monitoring System (CMS) of different degrees of fidelity, where a higher fidelity CMS would allow the blade state to be determined with a higher precision. The same model is then applied for the scheduled maintenance technique. The improved state information obtained from these techniques is then used to derive an optimal maintenance strategy. The difference between the value of the turbine with and without the inspection type can be interpreted as the value of the inspection. The results indicate that a higher fidelity (and more expensive) inspection method does not necessarily yield the highest value, and, that there is an optimal level of fidelity that results in maximum value. The results also aim to inform the operator of the impact of regional parameters such as wind speed, variance and maintenance costs to the optimal

Managing and controlling maintenance

International Nuclear Information System (INIS)

Chavez, G.; Perla, H.F.

1980-01-01

A well-planned maintenance-management program can bring organized yet flexible scheduling, improved productivity, and a ready-access data bank. The system detailed in the article, developed for a nuclear power plant, has application to any equipment-intensive facility. Key features of the system include: documentation of all work requirements and their completion; automated prioritizing of work orders; automatic generation of work orders for repetitive work, when due; work lists in priority sequence; deferred, standby, and outage work reports; labor and work-order backlog information; equipment work histories and cumulative failure data

Maintenance of nuclear chemical and fuel fabrication plants [Invited talk no. IT-3

International Nuclear Information System (INIS)

Prasad, A.M.

1981-01-01

Though the objective of the maintenance practices followed in nuclear facilities is to optimise production as in other conventional production plants, the radioactivity associated with nuclear materials is a major constraint in all maintenance jobs on equipment of the nuclear facility. Often non-routine maintenance have to be adopted. Maintenance aspect has to be taken into consideration at the design stage of the nuclear facility. The maintenance concept adopted in a nuclear facility depends on the type of plant and varies from full indirect remote maintenance to direct contact maintenance. This is illustrated by discussing maintenance practices followed in a fuel reprocessing plant, a high level radioactive waste management facility, a fuel fabrication plant, and a heavy water plant. Exposure of maintenance staff to radiation has to be kept within limits governed by safety regulations. Along with planning and scheduling of maintenance, training of manpower with mock-up facilities assumes importance and the maintenance jobs must be carried out under strict supervision. (M.G.B.)

Maintenance of nuclear power plants

International Nuclear Information System (INIS)

Migaud, D.; Hutin, J.P.; Jouette, I.; Eymond, P.; Devie, P.; Cudelou, C.; Magnier, S.; Frydman, M.

2016-01-01

This document gathers different articles concerning the maintenance of the French nuclear power plants. The first article analyses the impact of the recent law on the energetic transition that sets the share of nuclear power at 50% of the electricity produced by 2025. A consequence may be the decommissioning of 17 to 20 reactors by 2025 and the huge maintenance program called 'Grand Carenage' whose aim is to extend operating life over 40 years will have to be re-considered in order to avoid useless expenses. The second article shows that in 2015 the French nuclear reactor fleet got very good results in terms of availability and safety. There were 49 scheduled outages and among them some ended ahead of time. The third article describes the specificities of the maintenance of a nuclear power plant, for instance the redundancy of some systems implies that maintenance has to deal with systems that have never functioned but must be ready to operate at any moment. Another specificity is the complexity of a nuclear power plant that implies an essential phase of preparation for maintenance operations. Because of safety requirements any maintenance operation has to be controlled, checked and may provide feedback. The fourth article presents the 'Grand Carenage' maintenance program that involves the following operations: the replacement of steam generators, the re-tubing of condensers, the replacement of the filtering drums used for cooling water, the testing of the reactor building, the hydraulic test of the primary circuit and the inspection of the reactor vessel. The fifth article focuses on the organization of the work-site for maintenance operations and the example of the Belleville-sur-Loire is described in the sixth article. Important maintenance operations like 'Grand Carenage' requires a strong collaboration with a network of specialized enterprises and as no reactor (except Flamanville EPR) is being built in France, maintenance

Scheduling the scheduling task : a time management perspective on scheduling

NARCIS (Netherlands)

Larco Martinelli, J.A.; Wiers, V.C.S.; Fransoo, J.C.

2013-01-01

Time is the most critical resource at the disposal of schedulers. Hence, an adequate management of time from the schedulers may impact positively on the scheduler’s productivity and responsiveness to uncertain scheduling environments. This paper presents a field study of how schedulers make use of

Preventive maintenance program of motorized operated valves (MOV) at Cernavoda NPP

International Nuclear Information System (INIS)

Groza, M.; Moldoveanu, Edy

2001-01-01

This is a Power Point presentation. The following objectives are addressed: A. Determine the target of MOV program; B. Define the strategy for MOV; C. Establish the MOV program execution phases; D. Identification of key parameters; E. Examples. The target of MOV program is to improve the safety by ensuring the adequacy of safety valves and the reliability of safety equipment and, subsequently, to ensure the economic operation of the plant. Consequences of MV malfunction are indicated. The strategy for MOV program development is both general, namely, to define the minimal requirements of preventive /corrective maintenance activities for all MOV's according to design/ manufacture specification and particular, namely to identify MV's specific problems and the need for increasing/decreasing the preventing maintenance tasks or frequency established in 'general' MOV program. Strategy for MOV program development implies: - Establish MOV program applicability; - Develop diagnostic strategy (define key parameters ); - Perform program for engineering review; - Establish program for preventive maintenance; - Revise procedures for operating and maintenance tests; - Dynamic evaluation of MOV. The program execution phases are listed as follows: 1. Perform risk assessment of the MOV's to determine criticality level (program applicability); 2. Collect data to fill in MOV Application Data Sheet; 3. Perform engineering review to determine functional parameters acceptable range and determine key parameters; 4. Analysis for maintenance tasks / frequencies selection and determination of implementing actions (engineer review); 5. Prepare work packages for availability confirmation; 6. Schedule and plan corrective actions or provide input to other programs; 7. Schedule and plan implementing actions in preparation for program field execution; 8. Program field implementation; 9. Program monitoring, evaluation and optimization. The criteria defining the key operational and maintenance

Examples of in-service inspections and typical maintenance schedule for low-power research reactors

International Nuclear Information System (INIS)

Boeck, H.

1997-01-01

In-service inspection methods for low-power research reactors are described which have been developed during the past 37 years of the operation of the TRIGA reactor Vienna. Special tools have been developed during this period and their application for maintenance and in-serve inspection is discussed. Two practical in-service inspections at a TRIGA reactor and at a MTR reactor are presented. Further a typical maintenance plan for a TRIGA reactor is listed in the annex. (author)

Preventive maintenance technology for nuclear power stations

International Nuclear Information System (INIS)

Miyazawa, Tatsuo

1992-01-01

With the increase of the number of nuclear power plants in operation and the number of years of operation, the improvement of reliability and the continuation of safe operation have become more important, and the expectation for preventive maintenance technology has also heightened. The maintenance of Japanese nuclear power plants is based on the time schedule maintenance mainly by the regular inspection carried out every year, but the monitoring of the conditions of various machinery and equipment in operation has been performed widely. In this report, the present state of checkup and inspection technologies and the monitoring and diagnostic technologies for operational condition, which are the key technologies of preventive maintenance, are described. As the checkup and inspection technologies, ultrasonic flow detection technology, phased array technology, Amplituden und Laufzeit Orts Kurven method and X-ray CT, and as the monitoring and diagnostic technologies for operational condition, the diagnosis support system for BWR plants 'PLADIS', those for rotary machines, those for turbogenerators, those for solenoid valves, the mechanization of patrol works and the systematizing technology are reported. (K.I.)

Joint optimization of economic production quantity and preventive maintenance with considering multi-products and reserve time

Directory of Open Access Journals (Sweden)

Xuejuan Liu

2017-07-01

Originality/value: In modern companies, the production planning and maintenance schedule share the same system, and traditional research about two activities is separated, that always generate conflicts, such as inadequate or excessive maintenance, and shortages, etc., so we develop the integrated EPQ and PM model to avoid these undesirable effects.

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

Dataset Documentation for the ERTMS-Oriented Signalling Maintenance in the Danish Railway System

DEFF Research Database (Denmark)

M. Pour, Shahrzad

2017-01-01

This documentation provides information about the dataset generated as part of a PhD thesis (Towards Signalling Maintenance Scheduling Problem for European Railway Traffic Management System ) for the signaling maintenance of the Danish railway system . The data instances (M.Pour 2018a; M.Pour 2018b......) have been created for the purpose of adaptation to the newest railway signalling standard which is so called European Railway Traffic Management System(ERTMS). The chapter provides explanation of the different types of maintenance tasks in the ERTMS, followed by data definition. Furthermore...

40 CFR 94.211 - Emission-related maintenance instructions for purchasers.

Science.gov (United States)

2010-07-01

... agreement) which is identified by brand, trade, or corporate name. Such instructions also will not directly... whose function is not integral to the design and performance of the engine). (f) Scheduled maintenance... significantly degrade emission control and whose function is not integral to the design and performance of the...

Optimizing stormwater treatment practices a handbook of assessment and maintenance

CERN Document Server

Erickson, Andrew J; Gulliver, John S

2013-01-01

Optimizing Stormwater Treatment Practices: A Handbook of Assessment and Maintenance provides the information necessary for developing and operating an effective maintenance program for stormwater treatment. The book offers instructions on how to measure the level of performance of stormwater treatment practices directly and bases proposed maintenance schedules on actual performance and historical maintenance efforts and costs. The inspection methods, which are proven in the field and have been implemented successfully, are necessary as regulatory agencies are demanding evaluations of the performance of stormwater treatment practices. The authors have developed a three-tiered approach that offers readers a standard protocol for how to determine the effectiveness of stormwater treatment practices currently in place. This book also: Provides a standard protocol for how to determine the effectiveness of stormwater treatment practices Assists readers with identifying which assessment techniques to use for stormwa...

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)

Waste sampling and characterization facility (WSCF) maintenance implementation plan

International Nuclear Information System (INIS)

Heinemann, J.L.; Millard, G.E.

1997-08-01

This Maintenance Implementation Plan (MIP) is written to satisfy the requirements of the US Department of Energy (DOE) Order 4330.4B, Maintenance Management Program that specifies the general policy and objectives for the establishment of the DOE controlled maintenance programs. These programs provide for the management and performance of cost effective maintenance and repair of the DOE property, which includes facilities. This document outlines maintenance activities associated with the facilities operated by Waste Management Hanford, Inc. (WMH). The objective of this MIP is to provide baseline information for the control and execution of WMH Facility Maintenance activities relative to the requirements of Order 4330.4B, assessment of the WMH maintenance programs, and actions necessary to maintain compliance with the Order. Section 2.0 summarizes the history, mission and description of the WMH facilities. Section 3.0 describes maintenance scope and requirements, and outlines the overall strategy for implementing the maintenance program. Specific elements of DOE Order 4330.4B are addressed in Section 4.0, listing the objective of each element, a discussion of the WMH compliance methodology, and current implementation requirements with references to WMH and HNF policies and procedures. Section 5.0 addresses deviations from policy requirements, and Section 6.0 is a schedule for specific improvements in support of this MIP

Using Improved Ant Colony Algorithm to Investigate EMU Circulation Scheduling Problem

Directory of Open Access Journals (Sweden)

Yu Zhou

2014-01-01

Full Text Available High-speed railway is one of the most important ways to solve the long-standing travel difficulty problem in China. However, due to the high acquisition and maintenance cost, it is impossible for decision-making departments to purchase enough EMUs to satisfy the explosive travel demand. Therefore, there is an urgent need to study how to utilize EMU more efficiently and reduce costs in the case of completing a given task in train diagram. In this paper, an EMU circulation scheduling model is built based on train diagram constraints, maintenance constraints, and so forth; in the model solving process, an improved ACA algorithm has been designed. A case study is conducted to verify the feasibility of the model. Moreover, contrast tests have been carried out to compare the efficiency between the improved ACA and the traditional approaches. The results reveal that improved ACA method can solve the model with less time and the quality of each representative index is much better, which means that efficiency of the improved ACA method is higher and better scheduling scheme can be obtained.

Scheduling at the Los Alamos Neutron Science Center (LANSCE)

International Nuclear Information System (INIS)

Gallegos, F.R.

1999-01-01

The centerpieces of the Los Alamos Neutron Science Center (LANSCE) are a half-mile long 800-MeV proton linear accelerator and proton storage ring. The accelerator, storage ring, and target stations provide the protons and spallation neutrons that are used in the numerous basic research and applications experimental programs supported by the US Department of Energy. Experimental users, facility maintenance personnel, and operations personnel must work together to achieve the most program benefit within defined budget and resource constraints. In order to satisfy the experimental users programs, operations must provide reliable and high quality beam delivery. Effective and efficient scheduling is a critical component to achieve this goal. This paper will detail how operations scheduling is presently executed at the LANSCE accelerator facility

Centralized mission planning and scheduling system for the Landsat Data Continuity Mission

Science.gov (United States)

Kavelaars, Alicia; Barnoy, Assaf M.; Gregory, Shawna; Garcia, Gonzalo; Talon, Cesar; Greer, Gregory; Williams, Jason; Dulski, Vicki

2014-01-01

Satellites in Low Earth Orbit provide missions with closer range for studying aspects such as geography and topography, but often require efficient utilization of space and ground assets. Optimizing schedules for these satellites amounts to a complex planning puzzle since it requires operators to face issues such as discontinuous ground contacts, limited onboard memory storage, constrained downlink margin, and shared ground antenna resources. To solve this issue for the Landsat Data Continuity Mission (LDCM, Landsat 8), all the scheduling exchanges for science data request, ground/space station contact, and spacecraft maintenance and control will be coordinated through a centralized Mission Planning and Scheduling (MPS) engine, based upon GMV’s scheduling system flexplan9 . The synchronization between all operational functions must be strictly maintained to ensure efficient mission utilization of ground and spacecraft activities while working within the bounds of the space and ground resources, such as Solid State Recorder (SSR) and available antennas. This paper outlines the functionalities that the centralized planning and scheduling system has in its operational control and management of the Landsat 8 spacecraft.

Challenges encountered during an accelerated cogeneration plant construction and commissioning schedule

International Nuclear Information System (INIS)

Good, R.L.; Cox, T.P.; Vallejo, J.M.

1988-01-01

A decision was made in 1986 to proceed with a 110 magawatt grassroots cogeneration plant to supply the steam and electrical requirements of a large, integrated petrochemical manufacturing facility. Though some preliminary engineering had been done and long delivery equipment purchase orders had been let in the summer of 1986, detailed engineering did not commence until late October and construction until mid-December, 1986. Federal income tax consideration required that the project be in service prior to the end of 1987. This eleven month construction, commissioning, and start up schedule was achieved with 100 per cent operation occurring on December 22, 1987. Numerous challenges were met by the lean Project Team during this accelerated schedule. This paper discusses the development of: Project Team Staffing, Operator and Maintenance Staffing and Training, Commissioning Schedules and Staffing, solutions to Significant Technical Problems

Maintenance and control of apparatus for radiotherapy

International Nuclear Information System (INIS)

Wakui, Sho

1979-01-01

In order to perform the safe operation of radiotherapy apparatuses and to secure the accuracy in positioning patients and in setting up radiation beam, proper checking-up and maintenance schedule is necessary. Such schedule is described briefly and also the mechanical or electrical equipments designed for securing the safety and accuracy or eliminating in adequate operation are explained, especially on treatment tables and accessories, such as wedge filters, irradiation field indicators and pointers, and the devices for observing patients. The structures and the practical control of the following equipments are explained; standard treatment table, treatment table with a lifting column by oil pressure, mobile positioning control pedestal, positioning control pendaut, mechanical fuse cutter for the safeguard of table height movement, safety interlock to protect table from physical contact with radiation head in rotation and safeguard for arms of a patient in longitudinal movement of treatment table. For the maintenance and control of wedge filters, the kind of filter angle in use, the direction of filter in use and whether filter is used or not are exactly confirmed by adequate display. The direction mechanism of radiation field and the pointers are required to be strict for exact focusing of radiation. Various control apparatuses and monitoring apparatuses are described. (Kobatake, H.)

An Improved Multiobjective PSO for the Scheduling Problem of Panel Block Construction

Directory of Open Access Journals (Sweden)

Zhi Yang

2016-01-01

Full Text Available Uncertainty is common in ship construction. However, few studies have focused on scheduling problems under uncertainty in shipbuilding. This paper formulates the scheduling problem of panel block construction as a multiobjective fuzzy flow shop scheduling problem (FSSP with a fuzzy processing time, a fuzzy due date, and the just-in-time (JIT concept. An improved multiobjective particle swarm optimization called MOPSO-M is developed to solve the scheduling problem. MOPSO-M utilizes a ranked-order-value rule to convert the continuous position of particles into the discrete permutations of jobs, and an available mapping is employed to obtain the precedence-based permutation of the jobs. In addition, to improve the performance of MOPSO-M, archive maintenance is combined with global best position selection, and mutation and a velocity constriction mechanism are introduced into the algorithm. The feasibility and effectiveness of MOPSO-M are assessed in comparison with general MOPSO and nondominated sorting genetic algorithm-II (NSGA-II.

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

Implementing a least cost and risk focused maintenance process

International Nuclear Information System (INIS)

Darling, S.S.

1996-01-01

The paper will focus on the vital role maintenance, big ''M'' (spares, PM program, planning and scheduling, turning the wrench), has in preserving return of investment, and safety in operation of high risk high value facilities/platforms. The maintenance process of today and for the future must utilize risk assessment and reliability engineering techniques to prioritize plant resources. The new process must provide for high levels of safety assurance yet allow for improved generation and transmission capacity while maintaining adequate system reliability. This approach ultimately leads to continuous and sustained reduction in operating cost, improved production capacity, and a safety culture based upon a risk determent cost-beneficial decision process

New remote maintenance approach for TPX

International Nuclear Information System (INIS)

Davis, F.C.; Walker, M.S.; Brown, T.G.

1993-01-01

The Tokamak Physics Experiment (TPX), to be located at Princeton Plasma Physics Laboratory, will be a steady-state, high-performance fusion machine. It will use hydrogen fuel during its original operation, deuterium-deuterium (D-D) fuel for an extended intermediate period of time and then a limited number of runs using deuterium-tritium (D-T) fuel. The D-D operations wig generate neutron fluxes that will activate materials of the vacuum vessel. From that point on, the resulting ionizing radiation, which will continue to increase, particularly during D-T operation, will prevent personnel access into the vessel to perform either scheduled or unscheduled maintenance activities. All activities performed within the vacuum vessel must be accomplished using remote means. TPX has taken a new approach for remote maintenance of the components within the vacuum vessel. This document describes the system that is being developed

Proceedings of the CIM maintenance engineering/mine operators' conference; Comptes rendus du colloque de ICM sur l'ingenierie de maintenance et l'exploitation miniere

Energy Technology Data Exchange (ETDEWEB)

NONE

2008-07-01

This conference provided a forum to exchange knowledge and best practices that apply to to modern underground mining. It highlighted the synergy and co-operation that is essential for successful operations and maintenance practices. Solutions to mitigate increasing ventilation costs were presented along with possible alternatives to diesel powered equipment in order to maintain air quality at a level that is acceptable for human workers. The themes for the technical program were innovation and performance improvement; maintenance, and mining. The sessions were entitled: deep mining; environment; mining best practices; ground control; energy efficiency; research and development in mining; mining methods; narrow-vein mining; innovative equipment; predictive maintenance; research and development in maintenance; and, planning and scheduling. The conference featured 24 presentations, of which 5 have been catalogued separately for inclusion in this database. refs., tabs., figs.

Optimal scheduling of biocide dosing for seawater-cooled power and desalination plants

KAUST Repository

Mahfouz, Abdullah Bin

2011-02-13

Thermal desalination systems are typically integrated with power plants to exploit the excess heat resulting from the power-generation units. Using seawater in cooling the power plant and the desalination system is a common practice in many parts of the world where there is a shortage of freshwater. Biofouling is one of the major problems associated with the usage of seawater in cooling systems. Because of the dynamic variation in the power and water demands as well as the changes in the characteristics of seawater and the process, there is a need to develop an optimal policy for scheduling biocide usage and cleaning maintenance of the heat exchangers. The objective of this article is to introduce a systematic procedure for the optimization of scheduling the dosing of biocide and dechlorination chemicals as well as cleaning maintenance for a power production/thermal desalination plant. A multi-period optimization formulation is developed and solved to determine: the optimal levels of dosing and dechlorination chemicals; the timing of maintenance to clean the heat-exchange surfaces; and the dynamic dependence of the biofilm growth on the applied doses, the seawater-biocide chemistry, the process conditions, and seawater characteristics for each time period. The technical, economic, and environmental considerations of the system are accounted for. A case study is solved to elucidate the applicability of the developed optimization approach. © 2011 Springer-Verlag.

Maintenance of nuclear power plants

International Nuclear Information System (INIS)

Lashgari, Farbod.

1995-01-01

This paper is about maintenance of nuclear power plants. In part one, the outage management of nuclear power plants has described. Meaning of the outage and objectives of outage management is given in introduction. The necessity of a long-term outage strategy is shown in chapter one. The main parts of an outage are as follows: Planning; Preparation; Execution, Each of them and also post-outage review have been explained in the followed chapters. Part two deals with technical details of main primary components of nuclear power plant type WWER. After an introduction about WWER reactors, in each chapter first the general and detailed description of main primary components has given and then their maintenance schedules and procedures. Chapter about reactor and steam generator is related to both types of WWER-440 and WWER-1000, but chapter about reactor coolant pump has specified to WWER-1000 to be more in details.(author)

Web-Based Requesting and Scheduling Use of Facilities

Science.gov (United States)

Yeager, Carolyn M.

2010-01-01

Automated User's Training Operations Facility Utilization Request (AutoFUR) is prototype software that administers a Web-based system for requesting and allocating facilities and equipment for astronaut-training classes in conjunction with scheduling the classes. AutoFUR also has potential for similar use in such applications as scheduling flight-simulation equipment and instructors in commercial airplane-pilot training, managing preventive- maintenance facilities, and scheduling operating rooms, doctors, nurses, and medical equipment for surgery. Whereas requesting and allocation of facilities was previously a manual process that entailed examination of documents (including paper drawings) from different sources, AutoFUR partly automates the process and makes all of the relevant information available via the requester s computer. By use of AutoFUR, an instructor can fill out a facility-utilization request (FUR) form on line, consult the applicable flight manifest(s) to determine what equipment is needed and where it should be placed in the training facility, reserve the corresponding hardware listed in a training-hardware inventory database, search for alternative hardware if necessary, submit the FUR for processing, and cause paper forms to be printed. Auto-FUR also maintains a searchable archive of prior FURs.

Maintenance of nuclear medicine instruments

Energy Technology Data Exchange (ETDEWEB)

Ambro, P

1993-12-31

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 1 fig., 1 tab

Maintenance program, organization and procedures

International Nuclear Information System (INIS)

Schegk, J.R.R.

1986-01-01

The Rheinisch-Westfaelisches Elektrizitaetswerk AG (RWE) operates two pressurized water reactors (PWR) with 1.200 MW and 1.300 MW and two boiling water reactors (BWR) with an electrical output of 1.300 MW each. The PWR were commissioned in 1975 and 1977 respectively and have so far achieved a cumulative availability of 72%. The BWR started operating in 1984 and 1985. Since than they have been generating with a cumulative availability of 88%. The reliability of the nuclear power stations resulted in a trouble-free operation. For the last two years, the unscheduled non-availability amounted to 3,7% and 6,5% for the PWR and the BWR respectively. These favourable operating results derive inter alia from systematic preventive maintenance and consistent outage management. Apart from the personnel structure in the power stations the functional sequence of planning, control, performance as well as evaluation of maintenance results constitute a closed cycle. In order to ensure and support an effective cooperation of the above mentioned four functional sequences of a cycle, uniform and computer-assisted information and planning aids have been introduced such as task lists, job ordering, time scheduling and materials management. As a result of this preventive maintenance system the average refueling outage period is 35 to 42 days. (orig.)

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

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

Key Performance Indicators for Maintenance Management Effectiveness of Public Hospital Building

Directory of Open Access Journals (Sweden)

Farhana Omar Mardhiah

2017-01-01

Full Text Available Effectiveness of management in maintenance aspect holds the key element in influencing the performance of overall maintenance management. Similarly, public hospital building needs an effective maintenance management as this type of building in nature is one of the most complex issues in the field of maintenance. Improper building maintenance management adopted by the organization significantly will interrupt the overall operation of the building. Therefore, this paper is aim to identifying the key performance indicator (KPI of effectiveness of maintenance management for the public hospital building. A total of 32 set of questionnaires were distributed to the maintenance manager for each hospital in the northern region of peninsular Malaysia by using self-administration strategy. The survey answer was analyzed by performing descriptive analysis in SPSS. Overall, the result of descriptive analysis shows that all the ten factors of effectiveness of maintenance management are accepted as KPI since the mean value is at least 3.93 which classified as important and significant. The most significant factor of effectiveness of maintenance management is task planning and scheduling with the mean score of 4.35. While less significant factor is identify as maintenance approach with the value of mean score is 3.93. The both results indicates that the management need to have well-structured planning for the maintenance works and also need to embrace the exact strategy of maintenance approach in order to achieved better overall performance of maintenance management. This study may draw a standard practice for the government in assessing the performance of public facilities in terms of maintenance management.

Maintenance and disassembly considerations for the Technology Demonstration Facility

International Nuclear Information System (INIS)

Spampinato, P.T.

1983-01-01

The Technology Demonstration Facility (TDF) is a tandem-mirror design concept carried out under the direction of Lawrence Livermore National Laboratory. It was conceived as a near-term device with a mission of developing engineering technology in a D-T fusion environment. Overall maintenance and component disassembly were among the responsibilities of the Fusion Engineering Design Center (FEDC). A configuration evolved that was based on the operational requirements of the components, as well as the requirements for their replacements. Component lifetime estimates were used to estimate the frequency and the number of replacements. In addition, it was determined that the need for remote handling equipment followed within 1.5 years after initial start-up, emphasizing the direct relationship between developing maintenance scenarios/equipment and the device configuration. Many of the scheduled maintenance operations were investigated to first order, and preliminary handling equipment concepts were developed

Pilot Study for Maintenance Rule at KSNP

International Nuclear Information System (INIS)

Choi, Kwang Hee; Jeong, Hyeon Jong; Jee, Moon Hak; Hong, Sung Yull

2005-01-01

Maintenance Rule (MR), which was developed to monitor the effectiveness of maintenance in a nuclear power plant (NPP), has been received as highly successful program by and large since its implementation in 1996 in the United States. Korea has initiated two pilot programs to implement the Maintenance Rule program in 2003. Selected plants for the pilot implementation are Kori 3 and 4 units and Ulchin 3 and 4 units, where Kori 3 and 4 units are Westinghouse units and Ulchin 3 and 4 units are Korean Standardized Nuclear Power (KSNP) Plant units. This paper describes the results of each key tasks completed to date and insights gained from pilot study on the KSNP units. Currently, Scoping of the functions of maintenance rule and determination of safety significance level have been completed during first year. As first task, total 607 functions were identified and defined by detailed function analysis on 135 systems that cover all plant systems. About 55% of total functions are selected as within the scope of maintenance rule. Among these inscoped functions, 56% of scoped functions are safety related and 44% are non-safety related functions. Evaluation of safety significance for each function was determined by expert panel consist of eight experts in field of plant maintenance, operation, PSA, work schedule and system engineers. As a result, about 46% of functions were determined to be high safety significant functions and rest of the functions were classified as low safety significant. The remaining tasks that are included determination of performance criteria and preparation of implementing guideline will be performed in following years

A computerized event and maintenance data system at Loviisa nuclear power plant

International Nuclear Information System (INIS)

Jankala, K.E.; Saarelainen, P.; Vaurio, J.K.

1993-01-01

An on-line failure and maintenance event data system (which is a part of the Loviisa power plant information system) is described as developed and implemented at the Loviisa power plant. The system has been in operation since 1989, and the data base now covers more than 10 years of operation. The system contains a complete unavailability history, i.e. failures, repairs, replacements, scheduled or unscheduled preventive maintenance and periodic testing or service actions for any component that is relevant to plant safety, risk or economic production. The data base provides useful feedback from operating experience and can support e.g. studies on optimal maintenance and testing, planning of spare parts inventory and repair resources, updating of reliability parameters for risk studies, etc. (Z.S.) 4 refs

Constraint-based job shop scheduling with ILOG SCHEDULER

NARCIS (Netherlands)

Nuijten, W.P.M.; Le Pape, C.

1998-01-01

We introduce constraint-based scheduling and discuss its main principles. An approximation algorithm based on tree search is developed for the job shop scheduling problem using ILOG SCHEDULER. A new way of calculating lower bounds on the makespan of the job shop scheduling problem is presented and

Joint optimization of economic production quantity and preventive maintenance with considering multi-products and reserve time

International Nuclear Information System (INIS)

Liu, Xuejuan; Wang, Binrong

2017-01-01

Purpose: We deal with the problem of the joint determination of optimal economic production quantity (EPQ) and optimal preventive maintenance (PM) for a system that can produce multiple products alternately. The objective is to find the optimal number of production cycles and the PM policy simultaneously by minimizing the cost model. Design/methodology/approach: Considering the products go through the system in a sequence and a complete run of all products forms a production cycle. In each cycle, beyond production time we also consider some reserve time for maintenance and setup, shortage and overproduction may occur. We study the integrated problem based on two PM policies, and explain the situation with the other PM policies. The delay – time concept is used to model PM decisions. Findings: Using the integrated EPQ and PM model, we can calculate the optimal production planning and PM schedule simultaneously, especially we consider multiple products in each production cycle, which is more practical and economic than previous works. Originality/value: In modern companies, the production planning and maintenance schedule share the same system, and traditional research about two activities is separated, that always generate conflicts, such as inadequate or excessive maintenance, and shortages, etc., so we develop the integrated EPQ and PM model to avoid these undesirable effects.

Joint optimization of economic production quantity and preventive maintenance with considering multi-products and reserve time

Energy Technology Data Exchange (ETDEWEB)

Liu, Xuejuan; Wang, Binrong

2017-07-01

Purpose: We deal with the problem of the joint determination of optimal economic production quantity (EPQ) and optimal preventive maintenance (PM) for a system that can produce multiple products alternately. The objective is to find the optimal number of production cycles and the PM policy simultaneously by minimizing the cost model. Design/methodology/approach: Considering the products go through the system in a sequence and a complete run of all products forms a production cycle. In each cycle, beyond production time we also consider some reserve time for maintenance and setup, shortage and overproduction may occur. We study the integrated problem based on two PM policies, and explain the situation with the other PM policies. The delay – time concept is used to model PM decisions. Findings: Using the integrated EPQ and PM model, we can calculate the optimal production planning and PM schedule simultaneously, especially we consider multiple products in each production cycle, which is more practical and economic than previous works. Originality/value: In modern companies, the production planning and maintenance schedule share the same system, and traditional research about two activities is separated, that always generate conflicts, such as inadequate or excessive maintenance, and shortages, etc., so we develop the integrated EPQ and PM model to avoid these undesirable effects.

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

International Nuclear Information System (INIS)

Liu Min

2003-01-01

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

Analysis of the ITER ECH Upper Port Launcher remote maintenance using virtual reality

International Nuclear Information System (INIS)

Elzendoorn, Ben; de Baar, Marco; Chavan, Rene; Goodman, Timothy; Heemskerk, Cock; Heidinger, Roland; Kleefeldt, Klaus; Koning, Jarich; Sanders, Stephen; Spaeh, Peter; Strauss, Dirk; Verhoeven, Toon; Vreede, Fred de

2009-01-01

All ITER sub-systems of remote handling (RH) classes 1 and 2 have to be remotely maintainable. The maintenance strategy for these components has to ensure system availability after failure or scheduled maintenance. This paper shows how virtual reality (VR) simulation can be used as a tool to analyze the maintenance process, to predict the mean time to repair and to ensure the RH compatibility of one ITER sub-system, the Upper Port Launcher (UPL) . Special emphasis is put on the development of RH procedures and the identification of tooling requirements. The possibility to simulate RH logistics and repair actions in an early stage of the design process allows for the identification of those maintenance actions that require dedicated tests in the Launcher Handling Test Facility at Karlsruhe. The VR analysis, together with dedicated mock-up tests will demonstrate the RH compatibility of the UPL plug, provide input to the design of the Port Plug maintenance area in the ITER Hot Cell, and support the development of RH maintenance tooling.

Refinery scheduling

Energy Technology Data Exchange (ETDEWEB)

Magalhaes, Marcus V.; Fraga, Eder T. [PETROBRAS, Rio de Janeiro, RJ (Brazil); Shah, Nilay [Imperial College, London (United Kingdom)

2004-07-01

This work addresses the refinery scheduling problem using mathematical programming techniques. The solution adopted was to decompose the entire refinery model into a crude oil scheduling and a product scheduling problem. The envelope for the crude oil scheduling problem is composed of a terminal, a pipeline and the crude area of a refinery, including the crude distillation units. The solution method adopted includes a decomposition technique based on the topology of the system. The envelope for the product scheduling comprises all tanks, process units and products found in a refinery. Once crude scheduling decisions are Also available the product scheduling is solved using a rolling horizon algorithm. All models were tested with real data from PETROBRAS' REFAP refinery, located in Canoas, Southern Brazil. (author)

3D digital dynamic management of maintenance projects for nuclear power plant

International Nuclear Information System (INIS)

Wang Baizhong; Luo Yalin; Fang Hao; Ma Li; Zhang Jie; Wang Ruobing; Xie Min

2005-01-01

The whole process for the application of digital plant technique in the equipment transport in reactor building and the dynamic management of the spatial arrangement in Daya Bay Nuclear Power Station was introduced in the paper. The establishment of 3D digital Daya Bay plant, and the method and procedure to apply it in the nuclear power plant maintenance project have been discussed. This project utilizes the outer database to preserve the maintenance status of equipments, and avoids the damage or changing of the original 3D final model. Based on the maintenance procedure, the spatial arrangement and schedule for the maintenance of nuclear power station have been simulated and optimized for the whole process. This technique can simulate and optimize the arrangement and spatial arrangement for maintenance in limited space. It has been applied successfully in the reactor vessel head replacement for Unit 2 of Daya Bay NPP to shorten the time for key routes and the total time of this project by 16 hours and 92.5 hours, respectively. (author)

Dynamic optimization of maintenance and improvement planning for water main system: Periodic replacement approach

Energy Technology Data Exchange (ETDEWEB)

Kim, Jong Woo; Choi, Go Bong; Lee, Jong Min [Seoul National University, Seoul (Korea, Republic of); Suh, Jung Chul [Samchully Corporation, Seoul (Korea, Republic of)

2016-01-15

This paper proposes a Markov decision process (MDP) based approach to derive an optimal schedule of maintenance, rehabilitation and replacement of the water main system. The scheduling problem utilizes auxiliary information of a pipe such as the current state, cost, and deterioration model. The objective function and detailed algorithm of dynamic programming are modified to solve the periodic replacement problem. The optimal policy evaluated by the proposed algorithm is compared to several existing policies via Monte Carlo simulations. The proposed decision framework provides a systematic way to obtain an optimal policy.

The potential cost from passengers and how it impacts railway maintenance and renewal decisions

DEFF Research Database (Denmark)

Li, Rui; Landex, Alex; Nielsen, Otto Anker

To plan Maintenance and Renewals (M&R) for the heavy railway lines, scheduling work possession time and deciding the closure of railway line are quite challenging for Infrastructure Manager (IM) at tactical planning level. As usual, the direct costs such as the materials costs, man power price...

Automatic and manual operation modes of the TFTR maintenance manipulator

International Nuclear Information System (INIS)

Boehme, G.; Gumb, L.; Lotz, E.; Mueller, G.; Selig, M.

1987-01-01

The remote in-vessel operations scheduled to maintain the TFTR at Princeton, NJ, USA, comprise inspection, calibration, cleaning and protective tile replacement. The environmental conditions inside the torus vessel are ultra high vacuum, moderate γ-radiation and 150 0 C temperature of the vessel structure. The Princeton Plasma Physics Laboratory (PPPL) and KfK are jointly developing a maintenance manipulator (MM) which can perform these tasks. (orig./HP)

Moral, Ethical and Legal Considerations with the Use of Drugs for Performance Maintenance in the Canadian Forces

Science.gov (United States)

2009-10-01

drugs . Most controlled drugs with performance maintenance characteristics would fall under schedule 3 of the Act. CF members’ consumption of performance...21 - 4 RTO-MP-HFM-181 Disorder (ADHD) to increase attention. Caffeine itself is the world’s most widely used psychoactive drug and by far the...RTO-MP-HFM-181 21 - 1 Moral, Ethical and Legal Considerations with the Use of Drugs for Performance Maintenance in the Canadian Forces

海上风电机群维修排程在线多目标决策模型%On-line Multi-objective Decision Model for the Maintenance Scheduling of Offshore Wind Turbine Group

Institute of Scientific and Technical Information of China (English)

郭慧东; 王玮; 夏明超

2017-01-01

Based on the discussion of the offshore wind turbine characters different than thermal power generator, the framework and decision process of maintenance decision system for wind turbine was introduced, the maintenance operation flow and total maintenance cost of wind turbine was analyzed. On purpose of enhancing the maintenance efficiency and reducing the generation cost of offshore wind turbine group, an on-line multi-objective decision model for the daily maintenance scheduling of offshore wind turbine group was proposed in this paper,which minimizes the total maintenance cost and the workload balance with the constraints of budgets and human resources. The Kruskal spatial analysis algorithm of Geographic Information System (GIS) was applied to find the minimum spanning tree of return path of each maintenance operations combination. The Binary Particle Swarm Optimization (BPSO) was employed to solve the model, and obtains all non-dominated solution set of maintenance turbines combination and their exacted maintenance time. The simulation result shows the feasibility of the proposed model, and the effectiveness of the algorithm is verified.%结合海上风电机群特点,介绍风电机群维修决策系统框架和决策流程,分析风电机组维修作业流程和成本构成.以风电机群整体维修成本、作业工作量均衡性为目标函数,以维修中心物料和人力资源配置为约束条件,建立海上风电机群日间维修作业排程多目标决策模型.采用地理信息系统中的Kruskal空间分析算法寻找每组维修作业的往返路径最小生成树.应用带精英保留策略的离散粒子群算法求解模型,计算出全部待检修机组组合及其具体作业时段的非劣解集.仿真算例分析结果表明,模型可以降低维修总成本,验证了所提模型的可行性以及求解算法的有效性.

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

Science.gov (United States)

2015-09-01

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

Amphetamine increases schedule-induced drinking reduced by negative punishment procedures.

Science.gov (United States)

Pérez-Padilla, Angeles; Pellón, Ricardo

2003-05-01

d-Amphetamine has been reported to increase schedule-induced drinking punished by lick-dependent signalled delays in food delivery. This might reflect a drug-behaviour interaction dependent on the type of punisher, because no such effect has been found when drinking was reduced by lick-contingent electric shocks. However, the anti-punishment effect of amphetamine could be mediated by other behavioural processes, such as a loss of discriminative control or an increase in the value of delayed reinforcers. To test the effects of d-amphetamine on the acquisition and maintenance of schedule-induced drinking reduced by unsignalled delays in food delivery. Rats received 10-s unsignalled delays initiated by each lick after polydipsia was induced by a fixed-time 30-s food reinforcement schedule or from the outset of the experiment. Yoked-control rats received these same delays but independently of their own behaviour. d-Amphetamine (0.1-3.0 mg/kg) was then tested IP. d-Amphetamine dose-dependently increased and then decreased punished schedule-induced drinking. The drug led to dose-dependent reductions when the delays were not contingent or when they were applied from the outset of training. These results support the contention that d-amphetamine has an increasing effect on schedule-induced drinking that has been previously reduced by a negative punishment procedure. This effect cannot be attributed to other potentially involved processes, and therefore support the idea that drug effects on punished behaviour depend on punishment being delays in food or shock deliveries.

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

International Nuclear Information System (INIS)

Khan, I.

1995-01-01

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

Work Scheduling by Use of Worker Model in Consideration of Learning by On-The-Job Training

Science.gov (United States)

Tateno, Toshitake; Shimizu, Keiko

This paper deals with a method of scheduling manual work in consideration of learning by on-the-job training (OJT). In skilled work such as maintenance of trains and airplanes, workers must learn many tasks by OJT. While the work processing time of novice workers is longer than that of experts, the time will be reduced with repeated OJT. Therefore, OJT is important for maintaining the skill level and the long-term work efficiency of an organization. In order to devise a schedule considering OJT, the scheduler must incorporate a management function of workers to trace dynamically changing work experience. In this paper, after the relationship between scheduling problems and worker management problems is defined, a simulation method, in which a worker model and an agent-based mechanism are utilized, is proposed to derive the optimal OJT strategy toward high long-term performance. Finally, we present some case studies showing the effectiveness of OJT planning based on the simulation.

Cask system maintenance in the Federal Waste Management System

International Nuclear Information System (INIS)

Pope, R.B.; Rennich, M.J.; Medley, L.G.; Attaway, C.R.

1991-01-01

In early 1988, in support of the development of the transportation system for the Office of Civilian Radioactive Waste Management System (OCRWM), a feasibility study was undertaken to define a the concept for a stand-alone, ''green-field'' facility for maintaining the Federal Waste Management System (FWMS) casks. This study provided and initial layout facility design, an estimate of the construction costs, and an acquisition schedule for a Cask Maintenance Facility (CMF). It also helped to define the interfaces between the transportation system and the waste generators, the repository, and a Monitored Retrievable Storage (MRS) facility. The data, design, and estimated costs derived from the study have been organized for use in the total transportation system decision-making process. Most importantly, they also provide a foundation for continuing design and planning efforts. The feasibility study was based on an assumed stand-alone, ''green-field'' configuration. This design approach provides a comprehensive design evaluation, to guide the development of a cost estimate and to permit flexibility in locating the facility. The following sections provide background information on cask system maintenance, briefly summarizes some of the functional requirements that a CMF must satisfy, provides a physical description of the CMF, briefly discusses the cost and schedule estimates and then reviews the findings of the efforts undertaken since the feasibility study was completed. 15 refs., 3 figs

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...

On-line maintenance at Cofrentes NPP

International Nuclear Information System (INIS)

Roldan Vilches, J.; Moreno Matarranz, M. A.; Hermana Mendioroz, I.

1998-01-01

Cofrentes NPP has begun in 1997 activities related to At Power Preventive Maintenance over trains or systems which lead to a voluntary entry in a Limitative Condition of Operation (LCO) of the Technical Specifications. From others benefits, this program ha improved the risk management and the staff's knowledge over the functions and safety implications of the different systems, the better exploit of the resources, the co-ordination of the different organisations involved (Maintenance an Operation) and the reductions of works during shutdowns. Previous to each work, a feasibility study analyzes qualitative and quantitative (PSA), using the Risk Monitor, the implications on safety of all the tasks, assuring that the global safety of the Plant is always maintained. Tech. Spec. are analyzed in detail and also are analyzed situations of simultaneous unavailabilities of systems which could lead to a high risk situation. Two different risk controls are defined (punctual and accumulated) to assure that high risk situations will not be given. Finally, historical risk profile is analyzed to assure that the accumulated risk increase is not significant. Risk Monitor helps staff in the schedule and follow-up of the activities of On-Line Maintenance. Each one of the tasks are deeply planned and harshly analyzed and are carried out by high qualified workers. By the moment, this program is running with fully satisfaction on the Plant. (Author)

Development of inspection and maintenance program for reactor and reactivity control units in HANARO

International Nuclear Information System (INIS)

Cho, Yeong-Garp

1998-01-01

This paper summarizes the overall program for inspection and maintenance of reactor structure and Reactivity Control Units (RCU) of HANARO during lifetime. The long-term plan for in-service inspection is introduced in the viewpoint of the structural integrity of reactor and RCU, and the operability of RCU mechanism. This program includes the list of components to be inspected, the schedule of inspection and maintenance, and the development of special tools and test rig that are required for the remote inspection and maintenance of reactor and RCU components. Preliminary results of the evaluation on the lifetime of RCU components are summarized based on the operation history since the installation of reactor. A test rig will be designed and constructed for the purposes of verifying the prolonged lifetime of RCU components being used, the performance of special tools, and the rehearsal of maintenance work as well. (author)

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

ECS: Efficient Communication Scheduling for Underwater Sensor Networks

Directory of Open Access Journals (Sweden)

Lu Hong

2011-03-01

Full Text Available TDMA protocols have attracted a lot of attention for underwater acoustic sensor networks (UWSNs, because of the unique characteristics of acoustic signal propagation such as great energy consumption in transmission, long propagation delay and long communication range. Previous TDMA protocols all allocated transmission time to nodes based on discrete time slots. This paper proposes an efficient continuous time scheduling TDMA protocol (ECS for UWSNs, including the continuous time based and sender oriented conflict analysis model, the transmission moment allocation algorithm and the distributed topology maintenance algorithm. Simulation results confirm that ECS improves network throughput by 20% on average, compared to existing MAC protocols.

Guidance for the design and management of a maintenance plan to assure safety and improve the predictability of a DOE nuclear irradiation facility. Final report

International Nuclear Information System (INIS)

Booth, R.S.; Kryter, R.C.; Shepard, R.L.; Smith, O.L.; Upadhyaya, B.R.; Rowan, W.J.

1994-10-01

A program is recommended for planning the maintenance of DOE nuclear facilities that will help safety and enhance availability throughout a facility's life cycle. While investigating the requirements for maintenance activities, a major difference was identified between the strategy suitable for a conventional power reactor and one for a research reactor facility: the latter should provide a high degree of predicted availability (referred to hereafter as ''predictability'') to its users, whereas the former should maximize total energy production. These differing operating goals necessitate different maintenance strategies. A strategy for scheduling research reactor facility operation and shutdown for maintenance must balance safety, reliability,and predicted availability. The approach developed here is based on three major elements: (1) a probabilistic risk analysis of the balance between assured reliability and predictability (presented in Appendix C), (2) an assessment of the safety and operational impact of maintenance activities applied to various components of the facility, and (3) a data base of historical and operational information on the performance and requirements for maintenance of various components. These factors are integrated into a set of guidelines for designing a new highly maintainable facility, for preparing flexible schedules for improved maintenance of existing facilities, and for anticipating the maintenance required to extend the life of an aging facility. Although tailored to research reactor facilities, the methodology has broader applicability and may therefore be used to improved the maintenance of power reactors, particularly in anticipation of peak load demands

Work-in-progress report on maintenance good practices for motors in nuclear power generating stations - Part 2

International Nuclear Information System (INIS)

Eckstein, E.R.; Hall, A.R.; Kasper, S.; Smith, P.R.; Subudhi, M.

1988-01-01

Motor maintenance is addressed by a variety of industry standards, utility procedures and manufacture's instructions, as well as by recently published assessments of nuclear and non-nuclear operating experience and motor reliability data. This experience supports the premise that motor failure rates are in large part related to application stress factors such as operating time, environmental factors and vibration. Due to the large number of critical motors installed in a nuclear generating station, additional considerations are necessary to effectively schedule their preventive maintenance activities. Therefore, in this part, a method for prioritizing motor maintenance based on application stresses experienced by the motors is presented

Instructions, multiple schedules, and extinction: Distinguishing rule-governed from schedule-controlled behavior.

Science.gov (United States)

Hayes, S C; Brownstein, A J; Haas, J R; Greenway, D E

1986-09-01

Schedule sensitivity has usually been examined either through a multiple schedule or through changes in schedules after steady-state responding has been established. This study compared the effects of these two procedures when various instructions were given. Fifty-five college students responded in two 32-min sessions under a multiple fixed-ratio 18/differential-reinforcement-of-low-rate 6-s schedule, followed by one session of extinction. Some subjects received no instructions regarding the appropriate rates of responding, whereas others received instructions to respond slowly, rapidly, or both. Relative to the schedule in operation, the instructions were minimal, partially inaccurate, or accurate. When there was little schedule sensitivity in the multiple schedule, there was little in extinction. When apparently schedule-sensitive responding occurred in the multiple schedule, however, sensitivity in extinction occurred only if differential responding in the multiple schedule could not be due to rules supplied by the experimenter. This evidence shows that rule-governed behavior that occurs in the form of schedule-sensitive behavior may not in fact become schedule-sensitive even though it makes contact with the scheduled reinforcers.

Reliability in maintenance and design of elastomer sealed closures

International Nuclear Information System (INIS)

Lake, W.H.

1978-01-01

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

Multiobjective Optimization of Aircraft Maintenance in Thailand Using Goal Programming: A Decision-Support Model

Directory of Open Access Journals (Sweden)

Yuttapong Pleumpirom

2012-01-01

Full Text Available The purpose of this paper is to develop the multiobjective optimization model in order to evaluate suppliers for aircraft maintenance tasks, using goal programming. The authors have developed a two-step process. The model will firstly be used as a decision-support tool for managing demand, by using aircraft and flight schedules to evaluate and generate aircraft-maintenance requirements, including spare-part lists. Secondly, they develop a multiobjective optimization model by minimizing cost, minimizing lead time, and maximizing the quality under various constraints in the model. Finally, the model is implemented in the actual airline's case.

A choice function hyper-heuristic framework for the allocation of maintenance tasks in Danish railways

DEFF Research Database (Denmark)

Pour, Shahrzad M.; Drake, John H.; Burke, Edmund K.

2017-01-01

A new signalling system in Denmark aims at ensuring fast and reliable train operations, however imposes very strict time limits on recovery plans in the event of failure. As a result, it is necessary to develop a new approach to the entire maintenance scheduling process. In the largest region of ...

Schedules of Controlled Substances: Temporary Placement of 4-Fluoroisobutyryl Fentanyl into Schedule I. Temporary scheduling order.

Science.gov (United States)

2017-05-03

The Administrator of the Drug Enforcement Administration is issuing this temporary scheduling order to schedule the synthetic opioid, N-(4-fluorophenyl)-N-(1-phenethylpiperidin-4-yl)isobutyramide (4-fluoroisobutyryl fentanyl or para-fluoroisobutyryl fentanyl), and its isomers, esters, ethers, salts and salts of isomers, esters, and ethers, into schedule I pursuant to the temporary scheduling provisions of the Controlled Substances Act. This action is based on a finding by the Administrator that the placement of 4-fluoroisobutyryl fentanyl into schedule I of the Controlled Substances Act is necessary to avoid an imminent hazard to the public safety. As a result of this order, the regulatory controls and administrative, civil, and criminal sanctions applicable to schedule I controlled substances will be imposed on persons who handle (manufacture, distribute, reverse distribute, import, export, engage in research, conduct instructional activities or chemical analysis, or possess), or propose to handle, 4-fluoroisobutyryl fentanyl.

Scheduling techniques in the Request Oriented Scheduling Engine (ROSE)

Science.gov (United States)

Zoch, David R.

1991-01-01

Scheduling techniques in the ROSE are presented in the form of the viewgraphs. The following subject areas are covered: agenda; ROSE summary and history; NCC-ROSE task goals; accomplishments; ROSE timeline manager; scheduling concerns; current and ROSE approaches; initial scheduling; BFSSE overview and example; and summary.

Using Modern Methodologies with Maintenance Software

Science.gov (United States)

Streiffert, Barbara A.; Francis, Laurie K.; Smith, Benjamin D.

2014-01-01

Jet Propulsion Laboratory uses multi-mission software produced by the Mission Planning and Sequencing (MPS) team to process, simulate, translate, and package the commands that are sent to a spacecraft. MPS works under the auspices of the Multi-Mission Ground Systems and Services (MGSS). This software consists of nineteen applications that are in maintenance. The MPS software is classified as either class B (mission critical) or class C (mission important). The scheduling of tasks is difficult because mission needs must be addressed prior to performing any other tasks and those needs often spring up unexpectedly. Keeping track of the tasks that everyone is working on is also difficult because each person is working on a different software component. Recently the group adopted the Scrum methodology for planning and scheduling tasks. Scrum is one of the newer methodologies typically used in agile development. In the Scrum development environment, teams pick their tasks that are to be completed within a sprint based on priority. The team specifies the sprint length usually a month or less. Scrum is typically used for new development of one application. In the Scrum methodology there is a scrum master who is a facilitator who tries to make sure that everything moves smoothly, a product owner who represents the user(s) of the software and the team. MPS is not the traditional environment for the Scrum methodology. MPS has many software applications in maintenance, team members who are working on disparate applications, many users, and is interruptible based on mission needs, issues and requirements. In order to use scrum, the methodology needed adaptation to MPS. Scrum was chosen because it is adaptable. This paper is about the development of the process for using scrum, a new development methodology, with a team that works on disparate interruptible tasks on multiple software applications.

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

International Nuclear Information System (INIS)

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

2004-01-01

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

Maintenance of Structures, Systems and Components of the RSG-GAS Reactor as an Implementation of BAPETEN Regulation No. 5 Year 2011

International Nuclear Information System (INIS)

Aep Saepudin Catur; Dede Solehudin Fauzi; Djunaidi

2012-01-01

Maintenance activities for structures, systems and components of the reactor, consider prerequisites for the operation of the non power reactor. This activity is intended to ensure that the structures, systems and components function properly. Implementation of reactor maintenance carried out starting from programs establishment, scheduling, maintenance accomplishment and maintenance report. This paper will describe the implementation of reactor maintenance non power as required by BAPETEN regulation no.5, year 2011. By understanding correctly of this regulation, it is expected that maintenance activity of structures, systems and components of the reactor can be successfully performed. The RSG-GAS reactor has implemented various types of reactor maintenance based on BAPETEN regulation no.5 year 2011 properly. As a result failure of the structures, systems and components of the reactor can be minimized then they can be kept reliable. (author)

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 costs as compared to CBM and pre-scheduled maintenance.

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

Science.gov (United States)

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

1998-01-01

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

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...

Development of an intellectual maintenance management system. Development of trouble detection and troubleshooting evaluation system

International Nuclear Information System (INIS)

Suda, Kazunori; Yoshikawa, Shinji; Tani, Satoshi

1998-03-01

Many research activities are conducted to enhance cost performance and safety of nuclear power plants operation and maintenance. Concept of autonomous operating system to equal the role of operators and of maintenance personnel with artificial intelligence and autonomous robots has been developed. An intellectual maintenance management system has been developed to be equipped with decision making functions of maintenance personnel. The intellectual maintenance management system is in charge of maintenance function of an autonomous plant, which consists of plant-wide monitoring, evaluation of component integrity, and scheduling of maintenance activities. In other words, this system should be equipped with preventive maintenance and corrective maintenance functions those are currently loaded on personnel. In this report, we discussed condition monitoring maintenance in the preventive maintenance. We also reported a sensor validation system development for machinery condition monitoring and diagnosis. We adopted distributed and cooperative system construction technique, which is expected recently in applications to large-scale plants. This system has inter-agent communication function for signal transmission and reception among distributed physics models of machineries. The system has been constructed for water/steam system of the LMFBR power plant. The system has been validated to be capable of cooperative sensor validation by the distributed set of agents, with quantitative indication of sensor deviation based on a newly developed fuzzy algorithm with inter-agent cooperation. The derived reference parameter value from the inter-agent evaluations also stands for the alternative measurement to the malfunctioned sensor. (author)

2007 Wholesale Power Rate Schedules : 2007 General Rate Schedule Provisions.

Energy Technology Data Exchange (ETDEWEB)

United States. Bonneville Power Administration.

2006-11-01

This schedule is available for the contract purchase of Firm Power to be used within the Pacific Northwest (PNW). Priority Firm (PF) Power may be purchased by public bodies, cooperatives, and Federal agencies for resale to ultimate consumers, for direct consumption, and for Construction, Test and Start-Up, and Station Service. Rates in this schedule are in effect beginning October 1, 2006, and apply to purchases under requirements Firm Power sales contracts for a three-year period. The Slice Product is only available for public bodies and cooperatives who have signed Slice contracts for the FY 2002-2011 period. Utilities participating in the Residential Exchange Program (REP) under Section 5(c) of the Northwest Power Act may purchase Priority Firm Power pursuant to the Residential Exchange Program. Rates under contracts that contain charges that escalate based on BPA's Priority Firm Power rates shall be based on the three-year rates listed in this rate schedule in addition to applicable transmission charges. This rate schedule supersedes the PF-02 rate schedule, which went into effect October 1, 2001. Sales under the PF-07 rate schedule are subject to BPA's 2007 General Rate Schedule Provisions (2007 GRSPs). Products available under this rate schedule are defined in the 2007 GRSPs. For sales under this rate schedule, bills shall be rendered and payments due pursuant to BPA's 2007 GRSPs and billing process.

Project management with dynamic scheduling baseline scheduling, risk analysis and project control

CERN Document Server

Vanhoucke, Mario

2013-01-01

The topic of this book is known as dynamic scheduling, and is used to refer to three dimensions of project management and scheduling: the construction of a baseline schedule and the analysis of a project schedule's risk as preparation of the project control phase during project progress. This dynamic scheduling point of view implicitly assumes that the usability of a project's baseline schedule is rather limited and only acts as a point of reference in the project life cycle.

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

Science.gov (United States)

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

2018-02-01

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

NASA scheduling technologies

Science.gov (United States)

Adair, Jerry R.

1994-01-01

This paper is a consolidated report on ten major planning and scheduling systems that have been developed by the National Aeronautics and Space Administration (NASA). A description of each system, its components, and how it could be potentially used in private industry is provided in this paper. The planning and scheduling technology represented by the systems ranges from activity based scheduling employing artificial intelligence (AI) techniques to constraint based, iterative repair scheduling. The space related application domains in which the systems have been deployed vary from Space Shuttle monitoring during launch countdown to long term Hubble Space Telescope (HST) scheduling. This paper also describes any correlation that may exist between the work done on different planning and scheduling systems. Finally, this paper documents the lessons learned from the work and research performed in planning and scheduling technology and describes the areas where future work will be conducted.

Preventive maintenance and reliability-centered maintenance

International Nuclear Information System (INIS)

Anderson, J.G.

1989-01-01

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

75 FR 42831 - Proposed Collection; Comment Request for Form 1065, Schedule C, Schedule D, Schedule K-1...

Science.gov (United States)

2010-07-22

.../or continuing information collections, as required by the Paperwork Reduction Act of 1995, Public Law... Income, Credits, Deductions and Other Items), Schedule L (Balance Sheets per Books), Schedule M-1 (Reconciliation of Income (Loss) per Books With Income (Loss) per Return)), Schedule M-2 (Analysis of Partners...

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...

Analysis of Issues for Project Scheduling by Multiple, Dispersed Schedulers (distributed Scheduling) and Requirements for Manual Protocols and Computer-based Support

Science.gov (United States)

Richards, Stephen F.

1991-01-01

Although computerized operations have significant gains realized in many areas, one area, scheduling, has enjoyed few benefits from automation. The traditional methods of industrial engineering and operations research have not proven robust enough to handle the complexities associated with the scheduling of realistic problems. To address this need, NASA has developed the computer-aided scheduling system (COMPASS), a sophisticated, interactive scheduling tool that is in wide-spread use within NASA and the contractor community. Therefore, COMPASS provides no explicit support for the large class of problems in which several people, perhaps at various locations, build separate schedules that share a common pool of resources. This research examines the issue of distributing scheduling, as applied to application domains characterized by the partial ordering of tasks, limited resources, and time restrictions. The focus of this research is on identifying issues related to distributed scheduling, locating applicable problem domains within NASA, and suggesting areas for ongoing research. The issues that this research identifies are goals, rescheduling requirements, database support, the need for communication and coordination among individual schedulers, the potential for expert system support for scheduling, and the possibility of integrating artificially intelligent schedulers into a network of human schedulers.

Results of calendar year 1995 Well Inspection and Maintenance Program Y-12 Plant, Oak Ridge, Tennessee

International Nuclear Information System (INIS)

McMaster, B.W.

1996-07-01

This document is a compendium of results of the 1995 Monitor Well Inspection and Maintenance Program at the US Department of Energy's Oak Ridge Y-12 Plant. This report documents the work relating to well inspections and maintenance requests. Inspections are implemented in order to better assess the condition and maintenance needs of wells that are actively being monitored. Currently this approach calls for inspecting all wells on a routine (annual or triennial) basis which are: (1) in an active sampling program; (2) included in a hydrologic study; or (3) not in service, but not scheduled for plugging and abandonment. Routine inspections help to ensure that representative groundwater samples and hydrologic data are being collected, and contribute to the effective longevity of each well. This report formally presents well inspection and maintenance activities that were conducted at the Y-12 Plant from August through December 1995

Accelerating exact schedulability analysis for fixed-priority pre-emptive scheduling

NARCIS (Netherlands)

Hang, Y.; Jiale, Z.; Keskin, U.; Bril, R.J.

2010-01-01

The schedulability analysis for fixed-priority preemptive scheduling (FPPS) plays a significant role in the real-time systems domain. The so-called Hyperplanes Exact Test (HET) [1] is an example of an exact schedulability test for FPPS. In this paper, we aim at improving the efficiency of HET by

On line system monitoring and analysis for efficient maintenance management [Paper No.: I-10

International Nuclear Information System (INIS)

Verma, R.M.P.

1981-01-01

Continuously operating chemical plants and nuclear reactors with huge investments cannot afford unscheduled shut down, costly down time, undesired exposure of people to radiation and high cost of inventory. To obtain cost effectiveness in terms of increased plant availability with increased quality, safety and reliability of plant operations a good maintenance system is required. A preventive maintenance programme, though successful to a greater extent, has got the limitations of being based upon elapsed time, subjective approach or statistical data. Hence, maintenance action is mistimed. Preventive maintenance can become very effective if rational and scientific data on equipment under working conditions are available. It can be achieved through on-line predictive instruments like sound level and vibration analyzers, probologs, corrosmeters, strain gages, thermographic infrared sensors, on-line ferrographs, chromatographs, acoustic emission, eddy current ultrasonic and wireless sensors etc. Instruments help maintenance engineer to diagnose, inspect, monitor, and help in forecasting failures and scheduling the frequencies optimally for overhauls, replacements, lubrication etc. They are also helpful in establishing work load, manpower, resource planning and inventory control. This paper discusses real time computer based system as well as conventional instruments and techniques. (author)

Diagnostic aid and maintenance at the La Hague reprocessing plants

International Nuclear Information System (INIS)

Bern, J.B.; Chabert, J.

1989-01-01

The Cogema plant at La Hague is the world's leading nuclear fuel reprocessing plant. A major extension program was initiated in 1980. It includes the construction of a new 800 t/year capacity plant (UP3), to be commissioned in 1989, and the doubling of the capacity of the present plant (UP2 800) scheduled to go on stream in 1992. On the occasion of this huge capital investment, an overall assessment was made of the operating and maintenance systems of the site. The general objective was to achieve maximum productivity and availability, in view of: - the extreme importance of safety for the protection of workers and the environment, - the high level of automation required by the complexity of the process, - the inaccessibility of the nuclear equipment, the scale of the investment. To achieve this goal, a set of diagnostic and maintenance aid systems were developed and installed. A general site data network serves to link these systems and to distribute the corresponding data to the different users. This paper describes these different systems, presents the functionalities of the network and demonstrates the sequencing of the operations in a typical maintenance application

Web Publishing Schedule

Science.gov (United States)

Section 207(f)(2) of the E-Gov Act requires federal agencies to develop an inventory and establish a schedule of information to be published on their Web sites, make those schedules available for public comment. To post the schedules on the web site.

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.

FOREST HARVEST SCHEDULING PLAN INTEGRATED TO THE ROAD NETWORK

Directory of Open Access Journals (Sweden)

Pedro Henrique Belavenutti Martins da Silva

2016-03-01

Full Text Available In industrial forest plantations, the spatial distribution of management units for harvest scheduling influences the timber production cost and the non-renewable resources consumption, due to issues related to transport logistic. In this context, this research aimed to formulate Integer Linear Programming (ILP by means of the application of Floyd-Warshall network optimization algorithm to generate timber production routes, minimizing the production costs resulting from harvest activities and forest road maintenance. Then, scenarios were simulated considering different minimal harvest ages for Pinus spp. and Eucalyptus spp. stands. The planning horizon was five years with annual periodicity. The study area was 23,330 hectares of forests, located in Paraná state (southern Brazil. We compared the simulated scenarios according to the following parameter indicators: harvest income, building road network and the production unit cost. The decreasing of the minimal harvest age reduces the mean production of management units scheduled to be harvested, in other hand, it requires fewer roads to be built, and consequently increases the production unit cost. The solutions obtained by using ILP models presented an optimality gap lower than 0.1%.

Schedule Matters: Understanding the Relationship between Schedule Delays and Costs on Overruns

Science.gov (United States)

Majerowicz, Walt; Shinn, Stephen A.

2016-01-01

This paper examines the relationship between schedule delays and cost overruns on complex projects. It is generally accepted by many project practitioners that cost overruns are directly related to schedule delays. But what does "directly related to" actually mean? Some reasons or root causes for schedule delays and associated cost overruns are obvious, if only in hindsight. For example, unrealistic estimates, supply chain difficulties, insufficient schedule margin, technical problems, scope changes, or the occurrence of risk events can negatively impact schedule performance. Other factors driving schedule delays and cost overruns may be less obvious and more difficult to quantify. Examples of these less obvious factors include project complexity, flawed estimating assumptions, over-optimism, political factors, "black swan" events, or even poor leadership and communication. Indeed, is it even possible the schedule itself could be a source of delay and subsequent cost overrun? Through literature review, surveys of project practitioners, and the authors' own experience on NASA programs and projects, the authors will categorize and examine the various factors affecting the relationship between project schedule delays and cost growth. The authors will also propose some ideas for organizations to consider to help create an awareness of the factors which could cause or influence schedule delays and associated cost growth on complex projects.

RA Reactor operation and maintenance (I-IX), Part II, Task 3.08/04; Pogon i odrzavanje reaktora RA (I-IX), II Deo, Zadatak 3.08/04

Energy Technology Data Exchange (ETDEWEB)

Zecevic, V [Institute of Nuclear Sciences Boris Kidric, Reaktor RA, Vinca, Beograd (Serbia and Montenegro)

1963-12-15

Repair and maintenance work of the RA reactor components and equipment was longer than planned due to the following reasons: chemical decontamination of the reactor heavy water system indispensable for maintenance of the heavy water pumps; findings of contamination origin changed the maintenance schedule; some construction materials of the heavy water pumps which caused contamination had to be removed; a number of the planned operations had to be performed under increase level of gamma radiation which increased the time needed for repair. This report covers detailed description of all the maintenance and repair work done from 25 Jan to 22 Apr 1963.

Analysis and Enhancement of IEEE 802.15.4e DSME Beacon Scheduling Model

Directory of Open Access Journals (Sweden)

Kwang-il Hwang

2014-01-01

Full Text Available In order to construct a successful Internet of things (IoT, reliable network construction and maintenance in a sensor domain should be supported. However, IEEE 802.15.4, which is the most representative wireless standard for IoT, still has problems in constructing a large-scale sensor network, such as beacon collision. To overcome some problems in IEEE 802.15.4, the 15.4e task group proposed various different modes of operation. Particularly, the IEEE 802.15.4e deterministic and synchronous multichannel extension (DSME mode presents a novel scheduling model to solve beacon collision problems. However, the DSME model specified in the 15.4e draft does not present a concrete design model but a conceptual abstract model. Therefore, in this paper we introduce a DSME beacon scheduling model and present a concrete design model. Furthermore, validity and performance of DSME are evaluated through experiments. Based on experiment results, we analyze the problems and limitations of DSME, present solutions step by step, and finally propose an enhanced DSME beacon scheduling model. Through additional experiments, we prove the performance superiority of enhanced DSME.

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.

The development of a 3-d risk matrix for qualitative maintenance risk management

International Nuclear Information System (INIS)

Hsu, Pi-Lin; Lo, Chung-Kung

2009-01-01

The 3-D Risk Matrix is a web-based tool, developed by the Institute of Nuclear Energy research (INER), to assist plant personnel for qualitative assessment of operational risks inherent with scheduling of system/component maintenance and testing. This paper focuses on a software development for a three-dimensional risk matrix which serves as a sub-function embedded in the Maintenance Rule (MR) risk management tool used by the Taiwan's nuclear power plants. The color in any field of the matrix directly corresponds to the risk condition level of the related plant maintenance configuration. It also informs the operators via graphical interface of the remaining hours before reaching to the potentially more significant risk level. In the 3-D Risk Matrix, the risk levels can be quickly determined since the conditional Core Damage Frequency (CDF) and Large Early Release Frequency (LERF) for each expected and allowed out-of-service sub-systems or trains combination is pre-calculated by INERISKEN. The 3-D Risk Matrix will play an important role to enhance the MR risk management tool during the on-line maintenances in Taiwan's nuclear power plants

A strategic value management approach for energy and maintenance management in a building

Science.gov (United States)

Nawi, Mohd Nasrun Mohd; Dahlan, Nofri Yenita; Nadarajan, Santhirasegaran

2015-05-01

Fragmentation process is always been highlighted by the stakeholders in the construction industry as one of the `critical' issue that diminishing the opportunity for stakeholders that involved during the operation and maintenance stage to influence design decisions. Failure of design professionals to consider how a maintenance contractor or facility manager will construct the design thus results in higher operating cost, wastage, defects during the maintenance and operation process. Moving towards team integration is considered a significant strategy for overcoming the issue. Value Management is a style of management dedicated to guiding people and promoting innovation with the aim to improve overall building performance through structured, team-oriented exercises which make explicit, and appraise subsequent decisions, by reference to the value requirements of the clients. Accordingly, this paper discusses the fragmentation issue in more detail including the definition, causes and effects to the maintenance and operation of building and at the same time will highlighted the potential of VM integrated team approach as a strategic management approach for overcoming that issue. It also explores that the team integration strategy alleviates scheduling problems, delays and disputes during the construction process, and, hence, prevent harming the overall building performance.

Logistic optimization of maintenance management of pipeline network using operational research resources; Otimizacao logistica do gerenciamento de manutencoes na malha de gasodutos em operacao utilizando os recursos de pesquisa operacional

Energy Technology Data Exchange (ETDEWEB)

Madeira, Italo M [PETROBRAS S.A., Rio de Janeiro, RJ (Brazil); Andrade, Gustavo C. de [Universidade Federal Fluminense (UFF), Niteroi, RJ (Brazil)

2008-07-01

A Gas pipeline system is operated typically loaded every time and requires a continuous maintenance plan to prevent or correct faults that can compromise the shipping and the delivery of the product. In this meaning, this paper describes how to provide more integration between the elements from the pipeline management logistics to do the scheduling tasks of maintenance using operational research resources. This tool intends to discover with an optimal result, the best days for each maintenance intervention in pipeline doing an economically distributed maintenance plan. (author)

CAME-Computer Aided Maintenance Engineering: a new methodology to reduce maintenance life cycle cost pipelines (repair level, spares, preventive/scheduled/inspection and resources) by modeling, analysis and optimization

Energy Technology Data Exchange (ETDEWEB)

Bot, Yizhak [BQR Reliability Engineering Ltd. (Israel)

2005-07-01

In today's insecure and uncertain climate in the high-tech industry, where money is less accessible, companies are constantly searching for ways to cut expenses. Two important financial factors to consider are maintenance and down time when the equipment/system/processes are not functioning/operating. In this paper we shall describe a new technology, which will help designers and operators of complex systems to improve the reliability of the products and to reduce the maintenance cost, when they are used in field. These set of tools are interfaced to exist CAD/CAE and ERP/CMMS systems concurrently. (author)

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)

Principles of MONJU maintenance. Characteristic of MONJU maintenance and reflection of LWR maintenance experience to FBR

International Nuclear Information System (INIS)

Nakai, Satoru; Nishio, Ryuichi; Uchihashi, Masaya; Kaneko, Yoshihisa; Yamashita, Hironobu; Yamaguchi, Atsunori; Aoki, Takayuki

2014-01-01

A sodium cooled fast breeder reactor (FBR) has unique systems and components and different degradation mechanism from light water reactor (LWR) so that need to establish maintenance technology in accordance with its features. The examination of the FBR maintenance technology is carried out in the special committee for considering the maintenance for Monju established in the Japan Society of Maintenology (JSM). As a result of the study such as extraction of Monju maintenance feature, maintenance technology benchmark between Monju and LWR components and survey of LWR maintenance experience, it is clear that principles of maintenance are same as LWR, necessity of LWR maintenance experience reflection and points to be considered in Monju maintenance. The road map to establish a FBR maintenance technology in the technical aspect became clear and it is vital to acquire operation and maintenance experience of the plant to implement this road map, and to establish a fast reactor maintenance. (author)

29 CFR 825.203 - Scheduling of intermittent or reduced schedule leave.

Science.gov (United States)

2010-07-01

... leave intermittently or on a reduced leave schedule for planned medical treatment, then the employee... 29 Labor 3 2010-07-01 2010-07-01 false Scheduling of intermittent or reduced schedule leave. 825... OF LABOR OTHER LAWS THE FAMILY AND MEDICAL LEAVE ACT OF 1993 Employee Leave Entitlements Under the...

ATLAS construction schedule

CERN Multimedia

Kotamaki, M

The goal during the last few months has been to freeze and baseline as much as possible the schedules of various ATLAS systems and activities. The main motivations for the re-baselining of the schedules have been the new LHC schedule aiming at first collisions in early 2006 and the encountered delays in civil engineering as well as in the production of some of the detectors. The process was started by first preparing a new installation schedule that takes into account all the new external constraints and the new ATLAS staging scenario. The installation schedule version 3 was approved in the March EB and it provides the Ready For Installation (RFI) milestones for each system, i.e. the date when the system should be available for the start of the installation. TCn is now interacting with the systems aiming at a more realistic and resource loaded version 4 before the end of the year. Using the new RFI milestones as driving dates a new summary schedule has been prepared, or is under preparation, for each system....

Development techniques of total product maintenance

Energy Technology Data Exchange (ETDEWEB)

Kim, S. D.; Oh, Y. W.; Soong, W. S.; Oh, W. H

2000-06-01

Facilities should be maintained in solid operational condition and the time required for correcting the malfunctions should be minimized since the operational pause due to malfunctions would be one of the most influencing factors on the accomplishments of research goals. It is well-known that we are able to obtain about a 30% reduction of the disbursement through the scheduled pre-repairing processes and to minimize the duration of the malfunctions provided that the relevant factors were administered under systematic coordination. Hence, the development of the facility integrity management system is necessary in order to minimize the duration of the operational pause due to malfunctions with the least disbursement and to minimize the repair time, and also to maximize the efficiency of the budget execution, manpower organization and maintenance management.

Development techniques of total product maintenance

International Nuclear Information System (INIS)

Kim, S. D.; Oh, Y. W.; Soong, W. S.; Oh, W. H.

2000-06-01

Facilities should be maintained in solid operational condition and the time required for correcting the malfunctions should be minimized since the operational pause due to malfunctions would be one of the most influencing factors on the accomplishments of research goals. It is well-known that we are able to obtain about a 30% reduction of the disbursement through the scheduled pre-repairing processes and to minimize the duration of the malfunctions provided that the relevant factors were administered under systematic coordination. Hence, the development of the facility integrity management system is necessary in order to minimize the duration of the operational pause due to malfunctions with the least disbursement and to minimize the repair time, and also to maximize the efficiency of the budget execution, manpower organization and maintenance management

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

Results of calendar year 1994 monitor well inspection and maintenance program, Y-12 Plant, Oak Ridge, Tennessee

International Nuclear Information System (INIS)

McMaster, B.W.; Jones, S.B.; Sitzler, J.L.

1995-06-01

This document is a compendium of results of the calendar year 1994 Monitor Well Inspection and Maintenance Program at the Department of Energy Y-12 Plant in Oak Ridge, Tennessee. This report documents the work relating to well inspections and maintenance requests. Inspections are implemented in order to better assess the condition and maintenance needs of wells that are actively being monitored. Currently this approach calls for inspecting all wells on a routine (annual or triennial) basis which are: (1) in an active sampling program; (2) included in a hydrologic study; or (3) not in service, but not scheduled for plugging and abandonment. Routine inspections help to ensure that representative groundwater samples and hydrologic data are being collected, and contribute to the life expectancy of each well. This report formally presents well inspection and maintenance activities that were conducted at the Y-12 Plant during 1994. All inspections were conducted between April and December

Results of calendar year 1994 monitor well inspection and maintenance program, Y-12 Plant, Oak Ridge, Tennessee

Energy Technology Data Exchange (ETDEWEB)

McMaster, B.W. [Univ. of Tennessee, Knoxville, TN (United States); Jones, S.B.; Sitzler, J.L. [Oak Ridge National Lab., TN (United States)

1995-06-01

This document is a compendium of results of the calendar year 1994 Monitor Well Inspection and Maintenance Program at the Department of Energy Y-12 Plant in Oak Ridge, Tennessee. This report documents the work relating to well inspections and maintenance requests. Inspections are implemented in order to better assess the condition and maintenance needs of wells that are actively being monitored. Currently this approach calls for inspecting all wells on a routine (annual or triennial) basis which are: (1) in an active sampling program; (2) included in a hydrologic study; or (3) not in service, but not scheduled for plugging and abandonment. Routine inspections help to ensure that representative groundwater samples and hydrologic data are being collected, and contribute to the life expectancy of each well. This report formally presents well inspection and maintenance activities that were conducted at the Y-12 Plant during 1994. All inspections were conducted between April and December.

Plant process computer replacements - techniques to limit installation schedules and costs

International Nuclear Information System (INIS)

Baker, M.D.; Olson, J.L.

1992-01-01

Plant process computer systems, a standard fixture in all nuclear power plants, are used to monitor and display important plant process parameters. Scanning thousands of field sensors and alarming out-of-limit values, these computer systems are heavily relied on by control room operators. The original nuclear steam supply system (NSSS) vendor for the power plant often supplied the plant process computer. Designed using sixties and seventies technology, a plant's original process computer has been obsolete for some time. Driven by increased maintenance costs and new US Nuclear Regulatory Commission regulations such as NUREG-0737, Suppl. 1, many utilities have replaced their process computers with more modern computer systems. Given that computer systems are by their nature prone to rapid obsolescence, this replacement cycle will likely repeat. A process computer replacement project can be a significant capital expenditure and must be performed during a scheduled refueling outage. The object of the installation process is to install a working system on schedule. Experience gained by supervising several computer replacement installations has taught lessons that, if applied, will shorten the schedule and limit the risk of costly delays. Examples illustrating this technique are given. This paper and these examples deal only with the installation process and assume that the replacement computer system has been adequately designed, and development and factory tested

La programación del mantenimiento del alumbrado viario y el impacto en su eficiencia energética; The road lighting maintenance schedule and the impact in their energy efficiency

Directory of Open Access Journals (Sweden)

Israel Omar Mockey Coureaux

2011-06-01

Full Text Available Se presenta un estudio acerca de la influencia de las acciones de mantenimiento en las instalaciones de alumbradoviario. Se abordan los aspectos relacionados con las causas de depreciación de estos sistemas y las acciones demantenimiento para su corrección. Se conceptualiza la eficiencia energética para el caso del alumbrado viario y semencionan todos los aspectos relacionados con ello. Los autores llaman la atención acerca de que frecuentementelos análisis para incrementar la eficiencia de estos sistemas de alumbrado solo se centran en las posibilidades decambio y mejoramiento de las lámparas, balastos, luminarias, así como las técnicas de regulación y control. En elartículo se hace énfasis en cómo a través del establecimiento del programa de mantenimiento que se defina sepuede impactar en la eficiencia energética desde la etapa de diseño y durante su explotación, resaltando laspotencialidades en esta vía poco estudiada hasta este momento.   A study about maintenance actions influences in road lighting efficiency is presented. The aspects related with thecauses of the luminous depreciation of road lighting systems and the maintenance actions are approached for theircorrection. The energy efficiency is conceptualized for the road lighting case and all the aspects can be impacted toincrease it are mentioned. The authors emphasis stands out that attention that usually the analyses to increase theefficiency of these systems is frequently focused only on the possibilities of change and improvement of the lamps,ballasts, luminaries and the control and regulation techniques to increase the efficiency of road lighting. The paperanalyses how through a maintenance schedule it can impact on the energy efficiency from the design stage andduring their exploitation, standing out the potentialities in this way little studied until this moment.

La programación del mantenimiento del alumbrado viario y el impacto en su eficiencia energética;The road lighting maintenance schedule and the impact in their energy efficiency

Directory of Open Access Journals (Sweden)

Israel Omar Mockey- Coureaux

2011-06-01

Full Text Available Se presenta un estudio acerca de la influencia de las acciones de mantenimiento en las instalaciones de alumbrado viario. Se abordan los aspectos relacionados con las causas de depreciación de estos sistemas y las acciones de mantenimiento para su corrección. Se conceptualiza la eficiencia energética para el caso del alumbrado viario y se mencionan todos los aspectos relacionados con ello. Los autores llaman la atención acerca de que frecuentemente los análisis para incrementar la eficiencia de estos sistemas de alumbrado solo se centran en las posibilidades de cambio y mejoramiento de las lámparas, balastos, luminarias, así como las técnicas de regulación y control. En el artículo se hace énfasis en cómo a través del establecimiento del programa de mantenimiento que se defina se puede impactar en la eficiencia energética desde la etapa de diseño y durante su explotación, resaltando las potencialidades en esta vía poco estudiada hasta este momento.A study about maintenance actions influences in road lighting efficiency is presented. The aspects related with the causes of the luminous depreciation of road lighting systems and the maintenance actions are approached for their correction. The energy efficiency is conceptualized for the road lighting case and all the aspects can be impacted to increase it are mentioned. The authors emphasis stands out that attention that usually the analyses to increase the efficiency of these systems is frequently focused only on the possibilities of change and improvement of the lamps, ballasts, luminaries and the control and regulation techniques to increase the efficiency of road lighting. The paper analyses how through a maintenance schedule it can impact on the energy efficiency from the design stage and during their exploitation, standing out the potentialities in this way little studied until this moment.

FFTF and Advanced Reactors Transition Program Resource Loaded Schedule

Energy Technology Data Exchange (ETDEWEB)

GANTT, D.A.

2000-10-31

This Resource Load Schedule (RLS) addresses two missions. The Advanced Reactors Transition (ART) mission, funded by DOE-EM, is to transition assigned, surplus facilities to a safe and compliant, low-cost, stable, deactivated condition (requiring minimal surveillance and maintenance) pending eventual reuse or D&D. Facilities to be transitioned include the 309 Building Plutonium Recycle Test Reactor (PRTR) and Nuclear Energy Legacy facilities. This mission is funded through the Environmental Management (EM) Project Baseline Summary (PBS) RL-TP11, ''Advanced Reactors Transition.'' The second mission, the Fast Flux Test Facility (FFTF) Project, is funded through budget requests submitted to the Office of Nuclear Energy, Science and Technology (DOE-NE). The FFTF Project mission is maintaining the FFTF, the Fuels and Materials Examination Facility (FMEF), and affiliated 400 Area buildings in a safe and compliant standby condition. This mission is to preserve the condition of the plant hardware, software, and personnel in a manner not to preclude a plant restart. This revision of the Resource Loaded Schedule (RLS) is based upon the technical scope in the latest revision of the following project and management plans: Fast Flux Test Facility Standby Plan (Reference 1); Hanford Site Sodium Management Plan (Reference 2); and 309 Building Transition Plan (Reference 4). The technical scope, cost, and schedule baseline is also in agreement with the concurrent revision to the ART Fiscal Year (FY) 2001 Multi-Year Work Plan (MYWP), which is available in an electronic version (only) on the Hanford Local Area Network, within the ''Hanford Data Integrator (HANDI)'' application.

RTEMS CENTRE- Support and Maintenance CENTRE to RTEMS Operating System

Science.gov (United States)

Silva, H.; Constantino, A.; Coutunho, M.; Freitas, D.; Faustino, S.; Mota, M.; Colaço, P.; Zulianello, M.

2008-08-01

RTEMS stands for Real-Time Operating System for Multiprocessor Systems. It is a full featured Real Time Operating System that supports a variety of open APIs and interface standards. It provides a high performance environment for embedded applications, including a fixed-priority preemptive/non-preemptive scheduler, a comprehensive set of multitasking operations and a large range of supported architectures. Support and maintenance CENTRE to RTEMS operating system (RTEMS CENTRE) is a joint initiative of ESA-Portugal Task force, aiming to build a strong technical competence in the space flight (on- board) software, to offer support, maintenance and improvements to RTEMS. This paper provides a high level description of the current and future activities of the RTEMS CENTRE. It presents a brief description of the RTEMS operating system, a description of the tools developed and distributed to the community [1] and the improvements to be made to the operating system, including facilitation for the qualification of RTEMS (4.8.0) [2] for the space missions.

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

2014-01-01

The potential for short-term training to improve cognitive and sensory function 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. PMID:25111032

Implementing a customer focused continual business improvement program to improve the maintenance process

International Nuclear Information System (INIS)

Kharshafdjian, G.; Fisher, C.; Beres, T.; Brooks, S.; Forbes, S.; Krause, M.; McAuley, K.; Wendorf, M.

2006-01-01

Global market pressures and increasing competition demands that successful companies establish a continual business improvement program as part of implementing its business strategy. Such programs must be driven by the definition of quality from the customer's perspective. This customer quality focus often requires a change in all aspects of the business including products, services, processes and culture. This paper will describe how Atomic Energy of Canada Limited implemented a Continual Business Improvement Program in their Nuclear Laboratories Business Unit. In particular, to review how the techniques were applied to improve the maintenance process and the status of the project. Customer (internal users of the processes at CRL) feedback has shown repeatedly there is dissatisfaction of the maintenance process. Customers complain about jobs not getting done to schedule or being deferred. A project has been launched with the following goals: to improve the maintenance process customer satisfaction and increase trades wrench time by 30 minutes / trade / day. DMAIC (Define-Measure-Analyze-Improve-Control) methodology was applied to find out the Root Cause(s) of the problem, provide solutions, and implement improvements. The expected Operational Benefits include: Executing work efficiently to quality standards and business performance of the site, improve maintenance efficiencies, reduce cycle time for maintenance process and improve process yield, and improve customer and employee satisfaction. (author)

Implementing a customer focused continual business improvement program to improve the maintenance process

Energy Technology Data Exchange (ETDEWEB)

Kharshafdjian, G.; Fisher, C.; Beres, T.; Brooks, S.; Forbes, S.; Krause, M.; McAuley, K.; Wendorf, M. [Atomic Energy of Canada Limited, Chalk River, Ontario (Canada)

2006-07-01

Global market pressures and increasing competition demands that successful companies establish a continual business improvement program as part of implementing its business strategy. Such programs must be driven by the definition of quality from the customer's perspective. This customer quality focus often requires a change in all aspects of the business including products, services, processes and culture. This paper will describe how Atomic Energy of Canada Limited implemented a Continual Business Improvement Program in their Nuclear Laboratories Business Unit. In particular, to review how the techniques were applied to improve the maintenance process and the status of the project. Customer (internal users of the processes at CRL) feedback has shown repeatedly there is dissatisfaction of the maintenance process. Customers complain about jobs not getting done to schedule or being deferred. A project has been launched with the following goals: to improve the maintenance process customer satisfaction and increase trades wrench time by 30 minutes / trade / day. DMAIC (Define-Measure-Analyze-Improve-Control) methodology was applied to find out the Root Cause(s) of the problem, provide solutions, and implement improvements. The expected Operational Benefits include: Executing work efficiently to quality standards and business performance of the site, improve maintenance efficiencies, reduce cycle time for maintenance process and improve process yield, and improve customer and employee satisfaction. (author)

Optimal maintenance policies in incomplete repair models

International Nuclear Information System (INIS)

Kahle, Waltraud

2007-01-01

We consider an incomplete repair model, that is, the impact of repair is not minimal as in the homogeneous Poisson process and not 'as good as new' as in renewal processes but lies between these boundary cases. The repairs are assumed to impact the failure intensity following a virtual age process of the general form proposed by Kijima. In previous works field data from an industrial setting were used to fit several models. In most cases the estimated rate of occurrence of failures was that of an underlying exponential distribution of the time between failures. In this paper, it is shown that there exist maintenance schedules under which the failure behavior of the failure-repair process becomes a homogeneous Poisson process

Human reliability and plant operating efficiency: Are 12-hour work schedules cause for concern?

International Nuclear Information System (INIS)

Baker, T.L.

1992-01-01

Since the introduction of 12-h shifts to the US nuclear power industry only 8 yr ago, compressed workweek schedules have proliferated among operations departments at a phenomenal rate. Many plants that continue to use 8-h shifts during normal operations routinely change to scheduled 12-h shifts during refueling or maintenance outages. The most critical issue in the use of extended work shifts is whether alertness, physical stamina, or mental performance are compromised to the point of reducing safety or efficiency of nuclear power plant operation. Laboratory and field research sponsored by the National Institute of Occupational Safety and Health suggests that alertness, measured by self-ratings, and mental performance, measured by computer-based performance tests, are impaired on 12-h shifts compared with 8-h shifts. In contrast to these findings, plant operating efficiency and operator performance have been rated as improved in two field studies conducted in operating nuclear power plants (Fast Flux Test Facility, Washington and Ontario Hydro, Canada). A recent Electric Power Research Institute review of nuclear industry experience with 12-h shifts also suggests an overwhelmingly positive rating of 12-h schedules from both control room operators and management

Expert system for maintenance management of a boiling water reactor power plant

International Nuclear Information System (INIS)

Hong Shen; Liou, L.W.; Levine, S.; Ray, A.; Detamore, M.

1992-01-01

An expert system code has been developed for the maintenance of two boiling water reactor units in Berwick, Pennsylvania, that are operated by the Pennsylvania Power and Light Company (PP and L). The objective of this expert system code, where the knowledge of experienced operators and engineers is captured and implemented, is to support the decisions regarding which components can be safely and reliably removed from service for maintenance. It can also serve as a query-answering facility for checking the plant system status and for training purposes. The operating and maintenance information of a large number of support systems, which must be available for emergencies and/or in the event of an accident, is stored in the data base of the code. It identifies the relevant technical specifications and management rules for shutting down any one of the systems or removing a component from service to support maintenance. Because of the complexity and time needed to incorporate a large number of systems and their components, the first phase of the expert system develops a prototype code, which includes only the reactor core isolation coolant system, the high-pressure core injection system, the instrument air system, the service water system, and the plant electrical system. The next phase is scheduled to expand the code to include all other systems. This paper summarizes the prototype code and the design concept of the complete expert system code for maintenance management of all plant systems and components

Constraint-based scheduling applying constraint programming to scheduling problems

CERN Document Server

Baptiste, Philippe; Nuijten, Wim

2001-01-01

Constraint Programming is a problem-solving paradigm that establishes a clear distinction between two pivotal aspects of a problem: (1) a precise definition of the constraints that define the problem to be solved and (2) the algorithms and heuristics enabling the selection of decisions to solve the problem. It is because of these capabilities that Constraint Programming is increasingly being employed as a problem-solving tool to solve scheduling problems. Hence the development of Constraint-Based Scheduling as a field of study. The aim of this book is to provide an overview of the most widely used Constraint-Based Scheduling techniques. Following the principles of Constraint Programming, the book consists of three distinct parts: The first chapter introduces the basic principles of Constraint Programming and provides a model of the constraints that are the most often encountered in scheduling problems. Chapters 2, 3, 4, and 5 are focused on the propagation of resource constraints, which usually are responsibl...

Scheduling for decommissioning projects

International Nuclear Information System (INIS)

Podmajersky, O.E.

1987-01-01

This paper describes the Project Scheduling system being employed by the Decommissioning Operations Contractor at the Shippingport Station Decommissioning Project (SSDP). Results from the planning system show that the project continues to achieve its cost and schedule goals. An integrated cost and schedule control system (C/SCS) which uses the concept of earned value for measurement of performance was instituted in accordance with DOE orders. The schedule and cost variances generated by the C/SCS system are used to confirm management's assessment of project status. This paper describes the types of schedules and tools used on the SSDP project to plan and monitor the work, and identifies factors that are unique to a decommissioning project that make scheduling critical to the achievement of the project's goals. 1 fig

Program reference schedule baseline

International Nuclear Information System (INIS)

1986-07-01

This Program Reference Schedule Baseline (PRSB) provides the baseline Program-level milestones and associated schedules for the Civilian Radioactive Waste Management Program. It integrates all Program-level schedule-related activities. This schedule baseline will be used by the Director, Office of Civilian Radioactive Waste Management (OCRWM), and his staff to monitor compliance with Program objectives. Chapter 1 includes brief discussions concerning the relationship of the PRSB to the Program Reference Cost Baseline (PRCB), the Mission Plan, the Project Decision Schedule, the Total System Life Cycle Cost report, the Program Management Information System report, the Program Milestone Review, annual budget preparation, and system element plans. Chapter 2 includes the identification of all Level 0, or Program-level, milestones, while Chapter 3 presents and discusses the critical path schedules that correspond to those Level 0 milestones

Second-order schedules of token reinforcement with pigeons: effects of fixed- and variable-ratio exchange schedules.

Science.gov (United States)

Foster, T A; Hackenberg, T D; Vaidya, M

2001-09-01

Pigeons' key pecks produced food under second-order schedules of token reinforcement, with light-emitting diodes serving as token reinforcers. In Experiment 1, tokens were earned according to a fixed-ratio 50 schedule and were exchanged for food according to either fixed-ratio or variable-ratio exchange schedules, with schedule type varied across conditions. In Experiment 2, schedule type was varied within sessions using a multiple schedule. In one component, tokens were earned according to a fixed-ratio 50 schedule and exchanged according to a variable-ratio schedule. In the other component, tokens were earned according to a variable-ratio 50 schedule and exchanged according to a fixed-ratio schedule. In both experiments, the number of responses per exchange was varied parametrically across conditions, ranging from 50 to 400 responses. Response rates decreased systematically with increases in the fixed-ratio exchange schedules, but were much less affected by changes in the variable-ratio exchange schedules. Response rates were consistently higher under variable-ratio exchange schedules than tinder comparable fixed-ratio exchange schedules, especially at higher exchange ratios. These response-rate differences were due both to greater pre-ratio pausing and to lower local rates tinder the fixed-ratio exchange schedules. Local response rates increased with proximity to food under the higher fixed-ratio exchange schedules, indicative of discriminative control by the tokens.

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

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

International Nuclear Information System (INIS)

MOORE TL

2001-01-01

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

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

International Nuclear Information System (INIS)

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

1994-01-01

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

Perceptions of randomized security schedules.

Science.gov (United States)

Scurich, Nicholas; John, Richard S

2014-04-01

Security of infrastructure is a major concern. Traditional security schedules are unable to provide omnipresent coverage; consequently, adversaries can exploit predictable vulnerabilities to their advantage. Randomized security schedules, which randomly deploy security measures, overcome these limitations, but public perceptions of such schedules have not been examined. In this experiment, participants were asked to make a choice between attending a venue that employed a traditional (i.e., search everyone) or a random (i.e., a probability of being searched) security schedule. The absolute probability of detecting contraband was manipulated (i.e., 1/10, 1/4, 1/2) but equivalent between the two schedule types. In general, participants were indifferent to either security schedule, regardless of the probability of detection. The randomized schedule was deemed more convenient, but the traditional schedule was considered fairer and safer. There were no differences between traditional and random schedule in terms of perceived effectiveness or deterrence. Policy implications for the implementation and utilization of randomized schedules are discussed. © 2013 Society for Risk Analysis.

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

International Nuclear Information System (INIS)

Koo, Jwa Jin; Seong, Poong Hyun

2007-01-01

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

Design criteria document, Maintenance Shop/Support Facility, K-Basin Essential Systems Recovery, Project W-405

International Nuclear Information System (INIS)

Strehlow, M.W.B.

1994-01-01

During the next 10 years a substantial amount of work is scheduled in the K-Basin Area related to the storage and eventual removal of irradiated N-Reactor fuel. Currently, maintenance support activities are housed in existing structures that were constructed in the early 1950's. These forty-year-old facilities and their supporting services are substandard, leading to inefficiencies. Because of numerous identified deficiencies and the planned increase in the numbers of K-Basin maintenance personnel, adequate maintenance support facilities that allow efficient operations are needed. The objective of this sub-project of Project W-405 is to provide a maintenance and storage facility which meets the K-Basin Maintenance Organization requirements as defined in Attachment 1. In Reference A, existing guidelines and requirements were used to allocate space for the maintenance activities and to provide a layout concept (See Attachment 2). The design solution includes modifying the existing 190 K-E building to provide space for shops, storage, and administration support functions. The primary reason for the modification is to simplify siting/permitting and make use of existing infrastructure. In addition, benefits relative to design loads will be realized by having the structure inside 190K-E. The new facility will meet the Maintenance Organization approved requirements in Attachment 1 relating to maintenance activities, storage areas, and personnel support services. This sub-project will also resolve outstanding findings and/or deficiencies relating to building fire protection, HVAC requirements, lighting replacement/upgrades, and personnel facilities. Compliance with building codes, local labor agreements and safety standards will result

How should periods without social interaction be scheduled? Children's preference for practical schedules of positive reinforcement.

Science.gov (United States)

Luczynski, Kevin C; Hanley, Gregory P

2014-01-01

Several studies have shown that children prefer contingent reinforcement (CR) rather than yoked noncontingent reinforcement (NCR) when continuous reinforcement is programmed in the CR schedule. Preference has not, however, been evaluated for practical schedules that involve CR. In Study 1, we assessed 5 children's preference for obtaining social interaction via a multiple schedule (periods of fixed-ratio 1 reinforcement alternating with periods of extinction), a briefly signaled delayed reinforcement schedule, and an NCR schedule. The multiple schedule promoted the most efficient level of responding. In general, children chose to experience the multiple schedule and avoided the delay and NCR schedules, indicating that they preferred multiple schedules as the means to arrange practical schedules of social interaction. In Study 2, we evaluated potential controlling variables that influenced 1 child's preference for the multiple schedule and found that the strong positive contingency was the primary variable. © Society for the Experimental Analysis of Behavior.

A development of maintenance educational support method by using navigation method Pt. 4. A development of a paper prototype system for the RHR pump maintenance educational support

International Nuclear Information System (INIS)

Yoshino, Kenji; Hirotsu, Yuko; Fujimoto, Junzo; Tsumura, Joji

2004-01-01

This research establishes the new maintenance educational support prototype system for aiming at organization as Trinity (a supervision person, a construction person in charge, a work person in charge, and group length), and improvement in human reliability for the purpose of aiming at before hand prevention of a systematic error, human error, and the accident and a trouble. (1) This maintenance educational support: system made educational start to the educational end the structure navigated exactly, carrying out the exchange with a data base along with the road map which divided action (act) of the work process and worker concerning RHR pump maintenance work for a participant etc. by class. (2) First, according to a participant's attribute, this educational support system performs educational support (a question and reply) concerning an organization and organization, and judges knowledge and a nature type based on the result. Furthermore, educational support (a question and reply) concerning maintenance work is performed, and a knowledge level is judged based on the result. And it considered as the structure which performs the comprehensive judgment about an organization, organization, and the educational effect concerning maintenance work at the last. (3) The judgment pattern of the knowledge and nature after the educational support end concerning a participant's organization and organization was made into four kinds which consist of (1) organization priority and duty A type, (2) organization priority and an adaptable type, (3) individual priority and an adaptable type, and (4) individual priority and a duty priority type. (4) The judgment pattern of the knowledge level after the educational support end concerning maintenance work of a participant was used as three kinds of evaluation axes, schedule management, apparatus reliability capability, and human-being reliability. (author)

Scheduling with Time Lags

NARCIS (Netherlands)

X. Zhang (Xiandong)

2010-01-01

textabstractScheduling is essential when activities need to be allocated to scarce resources over time. Motivated by the problem of scheduling barges along container terminals in the Port of Rotterdam, this thesis designs and analyzes algorithms for various on-line and off-line scheduling problems

Automated Scheduling Via Artificial Intelligence

Science.gov (United States)

Biefeld, Eric W.; Cooper, Lynne P.

1991-01-01

Artificial-intelligence software that automates scheduling developed in Operations Mission Planner (OMP) research project. Software used in both generation of new schedules and modification of existing schedules in view of changes in tasks and/or available resources. Approach based on iterative refinement. Although project focused upon scheduling of operations of scientific instruments and other equipment aboard spacecraft, also applicable to such terrestrial problems as scheduling production in factory.

Schedule Analytics

Science.gov (United States)

2016-04-30

Warfare, Naval Sea Systems Command Acquisition Cycle Time : Defining the Problem David Tate, Institute for Defense Analyses Schedule Analytics Jennifer...research was comprised of the following high- level steps :  Identify and review primary data sources 1...research. However, detailed reviews of the OMB IT Dashboard data revealed that schedule data is highly aggregated. Program start date and program end date

The use of probabilistic risk assessment to satisfy the Nuclear Regulatory Commission's maintenance rule

International Nuclear Information System (INIS)

Dubord, R.M.

1993-05-01

Maintenance and inspection at nuclear power plants consumes a large portion of a utility's resources, making resource allocation for such procedures vital. The NRC Maintenance Rule, due to be implemented in July of 1996, requires utilities to select systems, structures, and components (SSCS) important to safety and to develop a monitoring program to ensure that these SSCs are capable of fulfilling their intended functions. In light of these concerns, two ratios were developed to compare the risk significance of individual components with the amount of plant staff time, or burden, associated with inspecting the component. These risk/burden ratios point out existing disparities between current inspection practices and safety concerns. These ratios can be used to develop new inspection schedules constituting a more equitable risk to burden distribution

Preemptive scheduling with rejection

NARCIS (Netherlands)

Hoogeveen, H.; Skutella, M.; Woeginger, Gerhard

2003-01-01

We consider the problem of preemptively scheduling a set of n jobs on m (identical, uniformly related, or unrelated) parallel machines. The scheduler may reject a subset of the jobs and thereby incur job-dependent penalties for each rejected job, and he must construct a schedule for the remaining

Preemptive scheduling with rejection

NARCIS (Netherlands)

Hoogeveen, J.A.; Skutella, M.; Woeginger, G.J.; Paterson, M.

2000-01-01

We consider the problem of preemptively scheduling a set of n jobs on m (identical, uniformly related, or unrelated) parallel machines. The scheduler may reject a subset of the jobs and thereby incur job-dependent penalties for each rejected job, and he must construct a schedule for the remaining

On line performance monitoring for predictive maintenance [Paper No.: VIA - 2

International Nuclear Information System (INIS)

Gupta, R.K.; Chandra, Rajesh

1981-01-01

There will always be progressive deterioration in the performance of dynamic equipment due to normal inevitable wear, malfunctions, failures and other reasons. In most cases it is possible to monitor some parameters of a system which would get progressively affected with the deterioration in the health of the system. By on-line monitoring of such predetermined parameters, compared with preset base data generated for a healthy system earlier, would prove very helpful in avoiding breakdowns and in proper planning of preventive and predictive maintenance. With increasing use of on-line computerised controls the generation of design base data and also the in-built self checking feature of monitoring the equipment health can be achieved by incorporating suitable software. This type of system will be helpful in: (a) predicting the life of component, (b) prewarning the operator about impending malfunctions, (c) establishing a maintenance schedule and spare inventory, and (d) analysing the failures. This type of centralised predictive maintenance is increasingly becoming important where: (a) the number of equipments are large, (b) the operation of equipment is critical from safety criteria, and (c) the minimum safety margin in the performance of the component is to be maintained. Keeping this in mind, the Fuel Handling System of Narora Atomic Power Project and the future power plants having computerised controls will have facility for on-line performance monitoring for predictive maintenance. The paper also describes methodology of the technique in detail, with a few representative cases. (author)

Designing cyclic appointment schedules for outpatient clinics with scheduled and unscheduled patient arrivals

NARCIS (Netherlands)

Kortbeek, Nikky; Zonderland, Maartje E.; Braaksma, Aleida; Vliegen, Ingrid M. H.; Boucherie, Richard J.; Litvak, Nelly; Hans, Erwin W.

2014-01-01

We present a methodology to design appointment systems for outpatient clinics and diagnostic facilities that offer both walk-in and scheduled service. The developed blueprint for the appointment schedule prescribes the number of appointments to plan per day and the moment on the day to schedule the

Designing cyclic appointment schedules for outpatient clinics with scheduled and unscheduled patient arrivals

NARCIS (Netherlands)

Kortbeek, Nikky; Zonderland, Maartje Elisabeth; Boucherie, Richardus J.; Litvak, Nelli; Hans, Elias W.

2011-01-01

We present a methodology to design appointment systems for outpatient clinics and diagnostic facilities that offer both walk-in and scheduled service. The developed blueprint for the appointment schedule prescribes the number of appointments to plan per day and the moment on the day to schedule the

Effects of a shortened depreciation schedule on the investment costs for combined heat and power; TOPICAL

International Nuclear Information System (INIS)

Kranz, Nicole; Worrell, Ernst

2001-01-01

We investigate and compare several generic depreciation methods to assess the effectiveness of possible policy measures with respect to the depreciation schedules for investments in combined heat and power plants in the United States. We assess the different depreciation methods for CHP projects of various sizes (ranging from 1 MW to 100 MW). We evaluate the impact of different depreciation schedules on the tax shield, and the resulting tax savings to potential investors. We show that a shorter depreciation cycle could have a substantial impact on the cost of producing power, making cogeneration more attractive. The savings amount to approximately 6-7 percent of capital and fixed operation and maintenance costs, when changing from the current system to a 7 year depreciation scheme with switchover from declining balance to straight line depreciation. Suggestions for further research to improve the analysis are given

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

A multi-level maintenance policy for a multi-component and multifailure mode system with two independent failure modes

International Nuclear Information System (INIS)

Zhu, Wenjin; Fouladirad, Mitra; Bérenguer, Christophe

2016-01-01

This paper studies the maintenance modelling of a multi-component system with two independent failure modes with imperfect prediction signal in the context of a system of systems. Each individual system consists of multiple series components and the failure modes of all the components are divided into two classes due to their consequences: hard failure and soft failure, where the former causes system failure while the later results in inferior performance (production reduction) of system. Besides, the system is monitored and can be alerted by imperfect prediction signal before hard failure. Based on an illustration example of offshore wind farm, in this paper three maintenance strategies are considered: periodic routine, reactive and opportunistic maintenance. The periodic routine maintenance is scheduled at fixed period for each individual system in the perspective of system of systems. Between two successive routine maintenances, the reactive maintenance is instructed by the imperfect prediction signal according to two criterion proposed in this study for the system components. Due to the high setup cost and practical restraints of implementing maintenance activities, both routine and reactive maintenance can create the opportunities of maintenance for the other components of an individual system. The life cycle of the system and the cost of the proposed maintenance policies are analytically derived. Restrained by the complexity from both the system failure modelling and maintenance strategies, the performances and application scope of the proposed maintenance model are evaluated by numerical simulations. - Highlights: • We study the life behavior of a complex system with two failure modes. • We consider the imperfect prediction signal of potential failure by monitoring. • We propose an integrated maintenance policy with three levels based on wind turbine. • We derive the mathematical cost formulations for the proposed maintenance policy.

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.

NASA Schedule Management Handbook

Science.gov (United States)

2011-01-01

The purpose of schedule management is to provide the framework for time-phasing, resource planning, coordination, and communicating the necessary tasks within a work effort. The intent is to improve schedule management by providing recommended concepts, processes, and techniques used within the Agency and private industry. The intended function of this handbook is two-fold: first, to provide guidance for meeting the scheduling requirements contained in NPR 7120.5, NASA Space Flight Program and Project Management Requirements, NPR 7120.7, NASA Information Technology and Institutional Infrastructure Program and Project Requirements, NPR 7120.8, NASA Research and Technology Program and Project Management Requirements, and NPD 1000.5, Policy for NASA Acquisition. The second function is to describe the schedule management approach and the recommended best practices for carrying out this project control function. With regards to the above project management requirements documents, it should be noted that those space flight projects previously established and approved under the guidance of prior versions of NPR 7120.5 will continue to comply with those requirements until project completion has been achieved. This handbook will be updated as needed, to enhance efficient and effective schedule management across the Agency. It is acknowledged that most, if not all, external organizations participating in NASA programs/projects will have their own internal schedule management documents. Issues that arise from conflicting schedule guidance will be resolved on a case by case basis as contracts and partnering relationships are established. It is also acknowledged and understood that all projects are not the same and may require different levels of schedule visibility, scrutiny and control. Project type, value, and complexity are factors that typically dictate which schedule management practices should be employed.

MOV reliability evaluation and periodic verification scheduling

Energy Technology Data Exchange (ETDEWEB)

Bunte, B.D.

1996-12-01

The purpose of this paper is to establish a periodic verification testing schedule based on the expected long term reliability of gate or globe motor operated valves (MOVs). The methodology in this position paper determines the nominal (best estimate) design margin for any MOV based on the best available information pertaining to the MOVs design requirements, design parameters, existing hardware design, and present setup. The uncertainty in this margin is then determined using statistical means. By comparing the nominal margin to the uncertainty, the reliability of the MOV is estimated. The methodology is appropriate for evaluating the reliability of MOVs in the GL 89-10 program. It may be used following periodic testing to evaluate and trend MOV performance and reliability. It may also be used to evaluate the impact of proposed modifications and maintenance activities such as packing adjustments. In addition, it may be used to assess the impact of new information of a generic nature which impacts safety related MOVs.

MOV reliability evaluation and periodic verification scheduling

International Nuclear Information System (INIS)

Bunte, B.D.

1996-01-01

The purpose of this paper is to establish a periodic verification testing schedule based on the expected long term reliability of gate or globe motor operated valves (MOVs). The methodology in this position paper determines the nominal (best estimate) design margin for any MOV based on the best available information pertaining to the MOVs design requirements, design parameters, existing hardware design, and present setup. The uncertainty in this margin is then determined using statistical means. By comparing the nominal margin to the uncertainty, the reliability of the MOV is estimated. The methodology is appropriate for evaluating the reliability of MOVs in the GL 89-10 program. It may be used following periodic testing to evaluate and trend MOV performance and reliability. It may also be used to evaluate the impact of proposed modifications and maintenance activities such as packing adjustments. In addition, it may be used to assess the impact of new information of a generic nature which impacts safety related MOVs

An integrated model of statistical process control and maintenance based on the delayed monitoring

International Nuclear Information System (INIS)

Yin, Hui; Zhang, Guojun; Zhu, Haiping; Deng, Yuhao; He, Fei

2015-01-01

This paper develops an integrated model of statistical process control and maintenance decision. The proposal of delayed monitoring policy postpones the sampling process till a scheduled time and contributes to ten-scenarios of the production process, where equipment failure may occur besides quality shift. The equipment failure and the control chart alert trigger the corrective maintenance and the predictive maintenance, respectively. The occurrence probability, the cycle time and the cycle cost of each scenario are obtained by integral calculation; therefore, a mathematical model is established to minimize the expected cost by using the genetic algorithm. A Monte Carlo simulation experiment is conducted and compared with the integral calculation in order to ensure the analysis of the ten-scenario model. Another ordinary integrated model without delayed monitoring is also established as comparison. The results of a numerical example indicate satisfactory economic performance of the proposed model. Finally, a sensitivity analysis is performed to investigate the effect of model parameters. - Highlights: • We develop an integrated model of statistical process control and maintenance. • We propose delayed monitoring policy and derive an economic model with 10 scenarios. • We consider two deterioration mechanisms, quality shift and equipment failure. • The delayed monitoring policy will help reduce the expected cost

Model Integrasi Penjadwalan Batch dan Penjadwalan Preventive Maintenance dengan Kriteria Minimisasi Biaya Simpan, Biaya Setup, Biaya Pm, serta Biaya Rework pada Mesin Stabil

Directory of Open Access Journals (Sweden)

Zahedi Zahedi

2014-06-01

Full Text Available This study developed a model of batch scheduling involving the unavailability machine to minimize setup costs, cost of preventive maintenance and the cost of rework in a stable machine. This model is considered necessary in order to understand the effect of the unavailability machine for production runs and to understand the effect on the batch production schedule. The results of this study indicate that the first and last run will not give single batch. Given a hypothetical example of how the model and algorithm developed solve the problem instance. 

Optimizing the Shunting Schedule of Electric Multiple Units Depot Using an Enhanced Particle Swarm Optimization Algorithm

Science.gov (United States)

Jin, Junchen

2016-01-01

The shunting schedule of electric multiple units depot (SSED) is one of the essential plans for high-speed train maintenance activities. This paper presents a 0-1 programming model to address the problem of determining an optimal SSED through automatic computing. The objective of the model is to minimize the number of shunting movements and the constraints include track occupation conflicts, shunting routes conflicts, time durations of maintenance processes, and shunting running time. An enhanced particle swarm optimization (EPSO) algorithm is proposed to solve the optimization problem. Finally, an empirical study from Shanghai South EMU Depot is carried out to illustrate the model and EPSO algorithm. The optimization results indicate that the proposed method is valid for the SSED problem and that the EPSO algorithm outperforms the traditional PSO algorithm on the aspect of optimality. PMID:27436998

Optimizing the Shunting Schedule of Electric Multiple Units Depot Using an Enhanced Particle Swarm Optimization Algorithm

Directory of Open Access Journals (Sweden)

Jiaxi Wang

2016-01-01

Full Text Available The shunting schedule of electric multiple units depot (SSED is one of the essential plans for high-speed train maintenance activities. This paper presents a 0-1 programming model to address the problem of determining an optimal SSED through automatic computing. The objective of the model is to minimize the number of shunting movements and the constraints include track occupation conflicts, shunting routes conflicts, time durations of maintenance processes, and shunting running time. An enhanced particle swarm optimization (EPSO algorithm is proposed to solve the optimization problem. Finally, an empirical study from Shanghai South EMU Depot is carried out to illustrate the model and EPSO algorithm. The optimization results indicate that the proposed method is valid for the SSED problem and that the EPSO algorithm outperforms the traditional PSO algorithm on the aspect of optimality.

Project Schedule Simulation

DEFF Research Database (Denmark)

Mizouni, Rabeb; Lazarova-Molnar, Sanja

2015-01-01

overrun both their budget and time. To improve the quality of initial project plans, we show in this paper the importance of (1) reflecting features’ priorities/risk in task schedules and (2) considering uncertainties related to human factors in plan schedules. To make simulation tasks reflect features......’ priority as well as multimodal team allocation, enhanced project schedules (EPS), where remedial actions scenarios (RAS) are added, were introduced. They reflect potential schedule modifications in case of uncertainties and promote a dynamic sequencing of involved tasks rather than the static conventional...... this document as an instruction set. The electronic file of your paper will be formatted further at Journal of Software. Define all symbols used in the abstract. Do not cite references in the abstract. Do not delete the blank line immediately above the abstract; it sets the footnote at the bottom of this column....

Maintenance implications of critical components in ITER CXRS upper port plug design

International Nuclear Information System (INIS)

Koning, Jarich; Jaspers, Roger; Doornink, Jan; Ouwehand, Bernard; Klinkhamer, Friso; Snijders, Bart; Sadakov, Sergey; Heemskerk, Cock

2009-01-01

Already in the early phase of a design for ITER, the maintenance aspects should be taken into account, since they might have serious implications. This paper presents the arguments in support of the case for the maintainability of the design, notably if this maintenance is to be performed by advanced remote methods. This structure is compliant to the evolving maintenance strategy of ITER. Initial results of a Failure Mode Effects and Criticality Analysis (FMECA) and a development risk analysis for the ITER upper port plug no. 3, housing the Charge Exchange Recombination Spectroscopy (CXRS) diagnostic, are employed for the definition of the maintenance strategy. The CXRS upper port plug is essentially an optical system which transfers visible light from the plasma into a fiber bundle. The most critical component in this path is the first mirror (M1) whose reflectivity degrades during operation due to deposition and/or erosion dominated effects. Amongst other measures to mitigate these effects, the strategy is to allow for a replacement of this mirror. Therefore it is mounted on a retractable central tube. The main purpose of this tube is to make frequent replacements possible without hindering operation. The maintenance method in terms of time, geometry and spare part policy has a large impact on cost of the system and time usage in the hot cell. Replacement of the tube under vacuum and magnetic field seems infeasible due to the operational risk involved. The preferred solution is to have a spare tube available which is replaced in parallel with other maintenance operations on the vessel, as to avoid any interference in the hot cell with the shutdown scheduling. This avoids having to refurbish a full port plug and also allows for a more frequent replacement of M1, as we can replace the mirror anytime the vacuum vessel is vented, estimated to be once a year.

Scheduling theory, algorithms, and systems

CERN Document Server

Pinedo, Michael L

2016-01-01

This new edition of the well-established text Scheduling: Theory, Algorithms, and Systems provides an up-to-date coverage of important theoretical models in the scheduling literature as well as important scheduling problems that appear in the real world. The accompanying website includes supplementary material in the form of slide-shows from industry as well as movies that show actual implementations of scheduling systems. The main structure of the book, as per previous editions, consists of three parts. The first part focuses on deterministic scheduling and the related combinatorial problems. The second part covers probabilistic scheduling models; in this part it is assumed that processing times and other problem data are random and not known in advance. The third part deals with scheduling in practice; it covers heuristics that are popular with practitioners and discusses system design and implementation issues. All three parts of this new edition have been revamped, streamlined, and extended. The reference...

Centralized operations and maintenance planning at the Atacama Large Millimeter/submillimeter Array (ALMA)

Science.gov (United States)

Lopez, Bernhard; Whyborn, Nicholas D.; Guniat, Serge; Hernandez, Octavio; Gairing, Stefan

2016-07-01

The Atacama Large Millimeter/submillimeter Array (ALMA) is a joint project between astronomical organizations in Europe, North America, and East Asia, in collaboration with the Republic of Chile. ALMA consists of 54 twelve-meter antennas and 12 seven-meter antennas operating as an aperture synthesis array in the (sub)millimeter wavelength range. Since the inauguration of the observatory back in March 2013 there has been a continuous effort to establish solid operations processes for effective and efficient management of technical and administrative tasks on site. Here a key aspect had been the centralized maintenance and operations planning: input is collected from science stakeholders, the computerized maintenance management system (CMMS) and from the technical teams spread around the world, then this information is analyzed and consolidated based on the established maintenance strategy, the observatory long-term plan and the short-term priorities definitions. This paper presents the high-level process that has been developed for the planning and scheduling of planned- and unplanned maintenance tasks, and for site operations like the telescope array reconfiguration campaigns. We focus on the centralized planning approach by presenting its genesis, its current implementation for the observatory operations including related planning products, and we explore the necessary next steps in order to fully achieve a comprehensive centralized planning approach for ALMA in steady-state operations.

Gain scheduling using the Youla parameterization

DEFF Research Database (Denmark)

Niemann, Hans Henrik; Stoustrup, Jakob

1999-01-01

Gain scheduling controllers are considered in this paper. The gain scheduling problem where the scheduling parameter vector cannot be measured directly, but needs to be estimated is considered. An estimation of the scheduling vector has been derived by using the Youla parameterization. The use...... in connection with H_inf gain scheduling controllers....

Ultrarush schedule of subcutaneous immunotherapy with modified allergen extracts is safe in paediatric age.

Science.gov (United States)

Morais-Almeida, Mário; Arêde, Cristina; Sampaio, Graça; Borrego, Luis Miguel

2016-01-01

Traditional subcutaneous immunotherapy up dosing with allergenic extracts has been shown to be associated with frequent adverse reactions. In recent studies it has been demonstrated that using modified extracts, namely allergoids, it is a safe and effective procedure particularly on accelerated schedules. However data assessing its safety in paediatric age is scarce. To evaluate the safety profile in paediatric population of using modified allergen extracts, in an ultrarush schedule, to reach the maintenance dose in the first day. We included children undergoing treatment with subcutaneous immunotherapy during a five-year period, using modified aeroallergen extracts, depigmented, polymerized with glutaraldehyde and adsorbed on aluminium hydroxide using an ultrarush induction phase. The type of adverse reactions during the ultrarush protocol was recorded. We studied 100 paediatric patients (57 males) with a mean age of 11.6 years (5 to 18 years; standard deviation, 3.3), all with moderate to severe persistent rhinitis, with or without allergic conjunctivitis, asthma and atopic eczema, sensitized to mites and/or pollens. All reached the maintenance dose of 0.5 mL in the first day, except 1 child. During the ultrarush protocol the total number of injections was 199. There were 21 local adverse reactions in 11 patients, 11 immediate and 10 delayed; from those, had clinical relevance 1 immediate and 4 delayed. Systemic reactions were recorded in 2 cases, both immediate and mild. The ultrarush protocol, without premedication, was a safe alternative to be used in paediatric age during the induction phase of subcutaneous immunotherapy using allergoid depigmented extracts.

NRC comprehensive records disposition schedule

International Nuclear Information System (INIS)

1982-07-01

Effective January 1, 1982, NRC will institute records retention and disposal practices in accordance with the approved Comprehensive Records Disposition Schedule (CRDS). CRDS is comprised of NRC Schedules (NRCS) 1 to 4 which apply to the agency's program or substantive records and General Records Schedules (GRS) 1 to 22 which apply to housekeeping or facilitative records. The schedules are assembled functionally/organizationally to facilitate their use. Preceding the records descriptions and disposition instructions for both NRCS and GRS, there are brief statements on the organizational units which accumulate the records in each functional area, and other information regarding the schedules' applicability

Experience in the application of S.A.T. for maintenance training at Cernavoda N.P.P. - U1

International Nuclear Information System (INIS)

Erdinici, Abdula

1999-01-01

specialist. Some of the outputs of this Task Force are: - carrier path for all maintenance positions; - revised JRTR's for all maintenance position; - training exception request, to recognize maintenance skills and experience gained during the commissioning/initial operation period; - long, medium and short term training schedules for maintenance personnel. Our maintenance training activities are based upon S.A.T. principles and our trainers have been indoctrinated to observe these principles. (author)

Integer 1/0 Knapsack Problem Dynamic Programming Approach in Building Maintenance Optimization

Directory of Open Access Journals (Sweden)

Viska Dewi Fawzy

2017-12-01

Full Text Available The most common problem in urban areas is the high public demand and the limited provision of housing. In meeting the needs of affordable housing for low income communities, the Government of Indonesia implements Rusunawa Project. Object of this research is Pandanarang Rusunawa. Rusunawa Pandanarang is one of the vertical housing in Cilacap that is facing deterioration issue and needs good maintenance management. This study aims at insetting priority and optimizing maintenance plan due to limited funds (limited budget and the amount of damage that must be repaired.This study uses one of the optimization methods of Dynamic Programing on the application of Integer 1/0 Knapsack Problem, to determine an schedule the maintenance activities. The Criteria that are used such as: the level of building components damage and the level of occupants participation. In the first criterion, the benefit (p is the percentage of damage that is fixed with the cost (w. While on the second criterion, the benefit (p is the percentage of occupant participation rate on the maintenance activities with the cost (w. For the budget of Rp 125.000.000, 00, it was obtained from the simulation that the value of the optimum solution on the first criterion at the 7th stage of 71.88% with total cost Rp 106.000.000, 00. At the second criterion, the value of the optimum solution at the 7th stage of 89.29% with total cost Rp 124.000.000, 00.

A cask maintenance facility feasibility study

International Nuclear Information System (INIS)

Rennich, M.J.; Medley, L.G.; Attaway, C.R.

1989-01-01

The Oak Ridge National Laboratory (ORNL) is developing a transportation system for spent nuclear fuel (SNF) and defense high level waste (HLW) as a part of the Federal Waste Management System (FWMS). In early 1988, a feasibility study was undertaken to design a stand-alone, ''green field'' facility for maintaining the FWMS casks. The feasibility study provided an initial layout facility design, an estimate of the construction cost, and an acquisition schedule for a Cask Maintenance Facility (CMF). The study also helped to define the interfaces between the transportation system and the waste generators, the repository, and a Monitored Retrievable Storage (MRS) facility. The data, design, and estimated costs resulting from the study have been organized for use in the total transportation system decision-making process. Most importantly, the feasibility study also provides a foundation for continuing design and planning efforts. Fleet servicing facility studies, operational studies from current cask system operators, a definition of the CMF system requirements, and the experience of others in the radioactive waste transportation field were used as a basis for the feasibility study. In addition, several cask handling facilities were visited to observe and discuss cask operations to establish the functions and methods of cask maintenance expected to be used in the facility. Finally, a peer review meeting was held at Oak Ridge, Tennessee in August, 1988, in which the assumptions, design, layout, and functions of the CMF were significantly refined. Attendees included representatives from industry, the repository and transportation operations

Outsourcing strategy and tendering methodology for the operation and maintenance of CERN’s cryogenic facilities

Science.gov (United States)

Serio, L.; Bremer, J.; Claudet, S.; Delikaris, D.; Ferlin, G.; Ferrand, F.; Pezzetti, M.; Pirotte, O.

2017-12-01

CERN operates and maintains the world largest cryogenic infrastructure ranging from ageing but well maintained installations feeding detectors, test facilities and general services, to the state-of-the-art cryogenic system serving the flagship LHC machine complex. A study was conducted and a methodology proposed to outsource to industry the operation and maintenance of the whole cryogenic infrastructure. The cryogenic installations coupled to non LHC-detectors, test facilities and general services infrastructure have been fully outsourced for operation and maintenance on the basis of performance obligations. The contractor is responsible for the operational performance of the installations based on a yearly operation schedule provided by CERN. The maintenance of the cryogenic system serving the LHC machine and its detectors has been outsourced on the basis of tasks oriented obligations, monitored by key performance indicators. CERN operation team, with the support of the contractor operation team, remains responsible for the operational strategy and performances. We report the analysis, strategy, definition of the requirements and technical specifications as well as the achieved technical and economic performances after one year of operation.

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

It Is Not Just about the Schedule: Key Factors in Effective Reference Desk Scheduling and Management

Science.gov (United States)

Sciammarella, Susan; Fernandes, Maria Isabel; McKay, Devin

2008-01-01

Reference desk scheduling is one of the most challenging tasks in the organizational structure of an academic library. The ability to turn this challenge into a workable and effective function lies with the scheduler and indirectly the cooperation of all librarians scheduled for reference desk service. It is the scheduler's sensitivity to such…

Approximating Preemptive Stochastic Scheduling

OpenAIRE

Megow Nicole; Vredeveld Tjark

2009-01-01

We present constant approximative policies for preemptive stochastic scheduling. We derive policies with a guaranteed performance ratio of 2 for scheduling jobs with release dates on identical parallel machines subject to minimizing the sum of weighted completion times. Our policies as well as their analysis apply also to the recently introduced more general model of stochastic online scheduling. The performance guarantee we give matches the best result known for the corresponding determinist...

Schedules of Controlled Substances: Temporary Placement of ortho-Fluorofentanyl, Tetrahydrofuranyl Fentanyl, and Methoxyacetyl Fentanyl Into Schedule I. Temporary amendment; temporary scheduling order.

Science.gov (United States)

2017-10-26

The Administrator of the Drug Enforcement Administration is issuing this temporary scheduling order to schedule the synthetic opioids, N-(2-fluorophenyl)-N-(1-phenethylpiperidin-4-yl)propionamide (ortho-fluorofentanyl or 2-fluorofentanyl), N-(1-phenethylpiperidin-4-yl)-N-phenyltetrahydrofuran-2-carboxamide (tetrahydrofuranyl fentanyl), and 2-methoxy-N-(1-phenethylpiperidin-4-yl)-N-phenylacetamide (methoxyacetyl fentanyl), into Schedule I. This action is based on a finding by the Administrator that the placement of ortho-fluorofentanyl, tetrahydrofuranyl fentanyl, and methoxyacetyl fentanyl into Schedule I of the Controlled Substances Act is necessary to avoid an imminent hazard to the public safety. As a result of this order, the regulatory controls and administrative, civil, and criminal sanctions applicable to Schedule I controlled substances will be imposed on persons who handle (manufacture, distribute, reverse distribute, import, export, engage in research, conduct instructional activities or chemical analysis, or possess), or propose to handle, ortho-fluorofentanyl, tetrahydrofuranyl fentanyl, and methoxyacetyl fentanyl.

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

Knowledge based maintenance

Energy Technology Data Exchange (ETDEWEB)

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

1998-12-31

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

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.)

Schedule-Aware Workflow Management Systems

Science.gov (United States)

Mans, Ronny S.; Russell, Nick C.; van der Aalst, Wil M. P.; Moleman, Arnold J.; Bakker, Piet J. M.

Contemporary workflow management systems offer work-items to users through specific work-lists. Users select the work-items they will perform without having a specific schedule in mind. However, in many environments work needs to be scheduled and performed at particular times. For example, in hospitals many work-items are linked to appointments, e.g., a doctor cannot perform surgery without reserving an operating theater and making sure that the patient is present. One of the problems when applying workflow technology in such domains is the lack of calendar-based scheduling support. In this paper, we present an approach that supports the seamless integration of unscheduled (flow) and scheduled (schedule) tasks. Using CPN Tools we have developed a specification and simulation model for schedule-aware workflow management systems. Based on this a system has been realized that uses YAWL, Microsoft Exchange Server 2007, Outlook, and a dedicated scheduling service. The approach is illustrated using a real-life case study at the AMC hospital in the Netherlands. In addition, we elaborate on the experiences obtained when developing and implementing a system of this scale using formal techniques.

Revisiting Symbiotic Job Scheduling

OpenAIRE

Eyerman , Stijn; Michaud , Pierre; Rogiest , Wouter

2015-01-01

International audience; —Symbiotic job scheduling exploits the fact that in a system with shared resources, the performance of jobs is impacted by the behavior of other co-running jobs. By coscheduling combinations of jobs that have low interference, the performance of a system can be increased. In this paper, we investigate the impact of using symbiotic job scheduling for increasing throughput. We find that even for a theoretically optimal scheduler, this impact is very low, despite the subs...

SPANR planning and scheduling

Science.gov (United States)

Freund, Richard F.; Braun, Tracy D.; Kussow, Matthew; Godfrey, Michael; Koyama, Terry

2001-07-01

SPANR (Schedule, Plan, Assess Networked Resources) is (i) a pre-run, off-line planning and (ii) a runtime, just-in-time scheduling mechanism. It is designed to support primarily commercial applications in that it optimizes throughput rather than individual jobs (unless they have highest priority). Thus it is a tool for a commercial production manager to maximize total work. First the SPANR Planner is presented showing the ability to do predictive 'what-if' planning. It can answer such questions as, (i) what is the overall effect of acquiring new hardware or (ii) what would be the effect of a different scheduler. The ability of the SPANR Planner to formulate in advance tree-trimming strategies is useful in several commercial applications, such as electronic design or pharmaceutical simulations. The SPANR Planner is demonstrated using a variety of benchmarks. The SPANR Runtime Scheduler (RS) is briefly presented. The SPANR RS can provide benefit for several commercial applications, such as airframe design and financial applications. Finally a design is shown whereby SPANR can provide scheduling advice to most resource management systems.

Self-scheduling with Microsoft Excel.

Science.gov (United States)

Irvin, S A; Brown, H N

1999-01-01

Excessive time was being spent by the emergency department (ED) staff, head nurse, and unit secretary on a complex 6-week manual self-scheduling system. This issue, plus inevitable errors and staff dissatisfaction, resulted in a manager-lead initiative to automate elements of the scheduling process using Microsoft Excel. The implementation of this initiative included: common coding of all 8-hour and 12-hour shifts, with each 4-hour period represented by a cell; the creation of a 6-week master schedule using the "count-if" function of Excel based on current staffing guidelines; staff time-off requests then entered by the department secretary; the head nurse, with staff input, then fine-tuned the schedule to provide even unit coverage. Outcomes of these changes included an increase in staff satisfaction, time saved by the head nurse, and staff work time saved because there was less arguing about the schedule. Ultimately, the automated self-scheduling method was expanded to the entire 700-bed hospital.

Development of Pavement Maintenance Management System (PMMS of Urban Road Network Using HDM-4 Model

Directory of Open Access Journals (Sweden)

Tanuj Chopra

2017-04-01

Full Text Available The aim of the study is to develop Pavement Maintenance Management System (PMMS for four road sections of urban road network (Patiala, Punjab, India using Highway Development and Management (HDM-4 model. The HDM-4 provides a deterministic approach in data input and process data of existing road condition, traffic volume and pavement composition to predict road deterioration as per the urban road conditions in terms of International Roughness Index (IRI value. This study presents the use of HDM-4 model for the computation of optimum Maintenance and Rehabilitation (M&R strategy for each road section and comparative study of scheduled and condition responsive M&R strategies. The results of present study will be useful for gaining better support for decision-makers for adequate and timely fund allocations for preservation of the urban road network.

A master surgical scheduling approach for cyclic scheduling in operating room departments

NARCIS (Netherlands)

van Oostrum, Jeroen M.; van Houdenhoven, M.; Hurink, Johann L.; Hans, Elias W.; Wullink, Gerhard; Kazemier, G.

This paper addresses the problem of operating room (OR) scheduling at the tactical level of hospital planning and control. Hospitals repetitively construct operating room schedules, which is a time-consuming, tedious, and complex task. The stochasticity of the durations of surgical procedures

Immunization Schedules for Adults

Science.gov (United States)

... ACIP Vaccination Recommendations Why Immunize? Vaccines: The Basics Immunization Schedule for Adults (19 Years of Age and ... diseases that can be prevented by vaccines . 2018 Immunization Schedule Recommended Vaccinations for Adults by Age and ...

Instant Childhood Immunization Schedule

Science.gov (United States)

... Recommendations Why Immunize? Vaccines: The Basics Instant Childhood Immunization Schedule Recommend on Facebook Tweet Share Compartir Get ... date. See Disclaimer for additional details. Based on Immunization Schedule for Children 0 through 6 Years of ...

Nontraditional work schedules for pharmacists.

Science.gov (United States)

Mahaney, Lynnae; Sanborn, Michael; Alexander, Emily

2008-11-15

Nontraditional work schedules for pharmacists at three institutions are described. The demand for pharmacists and health care in general continues to increase, yet significant material changes are occurring in the pharmacy work force. These changing demographics, coupled with historical vacancy rates and turnover trends for pharmacy staff, require an increased emphasis on workplace changes that can improve staff recruitment and retention. At William S. Middleton Memorial Veterans Affairs Hospital in Madison, Wisconsin, creative pharmacist work schedules and roles are now mainstays to the recruitment and retention of staff. The major challenge that such scheduling presents is the 8 hours needed to prepare a six-week schedule. Baylor Medical Center at Grapevine in Dallas, Texas, has a total of 45 pharmacy employees, and slightly less than half of the 24.5 full-time-equivalent staff work full-time, with most preferring to work one, two, or three days per week. As long as the coverage needs of the facility are met, Envision Telepharmacy in Alpine, Texas, allows almost any scheduling arrangement preferred by individual pharmacists or the pharmacist group covering the facility. Staffing involves a great variety of shift lengths and intervals, with shifts ranging from 2 to 10 hours. Pharmacy leaders must be increasingly aware of opportunities to provide staff with unique scheduling and operational enhancements that can provide for a better work-life balance. Compressed workweeks, job-sharing, and team scheduling were the most common types of alternative work schedules implemented at three different institutions.

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

OpenAIRE

Rachmad Hidayat; Nachnul Ansori; Ali Imron

2010-01-01

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

BIM-BASED SCHEDULING OF CONSTRUCTION

DEFF Research Database (Denmark)

Andersson, Niclas; Büchmann-Slorup, Rolf

2010-01-01

The potential of BIM is generally recognized in the construction industry, but the practical application of BIM for management purposes is, however, still limited among contractors. The objective of this study is to review the current scheduling process of construction in light of BIM...... and communicate. Scheduling on the detailed level, on the other hand, follows a stipulated approach to scheduling, i.e. the Last Planner System (LPS), which is characterized by involvement of all actors in the construction phase. Thus, the major challenge when implementing BIM-based scheduling is to improve...

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.

Evaluation of dose reduction versus standard dosing for maintenance of remission in patients with spondyloarthritis and clinical remission with anti-TNF (REDES-TNF): study protocol for a randomized controlled trial.

Science.gov (United States)

Pontes, Caridad; Gratacós, Jordi; Torres, Ferran; Avendaño, Cristina; Sanz, Jesús; Vallano, Antoni; Juanola, Xavier; de Miguel, Eugenio; Sanmartí, Raimon; Calvo, Gonzalo

2015-08-20

Dose reduction schedules of tumor necrosis factor antagonists (anti-TNF) as maintenance therapy in patients with spondyloarthritis are used empirically in clinical practice, despite the lack of clinical trials providing evidence for this practice. To address this issue the Spanish Society of Rheumatology (SER) and Spanish Society of Clinical Pharmacology (SEFC) designed a 3-year multicenter, randomized, open-label, controlled clinical trial (2 years for inclusion and 1 year of follow-up). The study is expected to include 190 patients with axial spondyloarthritis on stable maintenance treatment (≥4 months) with any anti-TNF agent at doses recommended in the summary of product characteristics. Patients will be randomized to either a dose reduction arm or maintenance of the dosing regimen as per the official labelling recommendations. Randomization will be stratified according to the anti-TNF agent received before study inclusion. Patient follow-up, visit schedule, and examinations will be maintained as per normal clinical practice recommendations according to SER guidelines. The study aims to test the hypothesis of noninferiority of the dose reduction strategy compared with standard treatment. The first patients were recruited in July 2012, and study completion is scheduled for the end of April 2015. The REDES-TNF study is a pragmatic clinical trial that aims to provide evidence to support a medical decision now made empirically. The study results may help inform clinical decisions relevant to both patients and healthcare decision makers. EudraCT 2011-005871-18 (21 December 2011).

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)

Network scheduling at Belene NPP construction site

International Nuclear Information System (INIS)

Matveev, A.

2010-01-01

Four types of schedules differing in the level of their detail are singled out to enhance the efficiency of Belene NPP Project implementation planning and monitoring: Level 1 Schedule–Summary Integrated Overall Time Schedule (SIOTS) is an appendix to EPC Contract. The main purpose of SIOTS is the large scale presentation of the current information on the Project implementation. Level 2 Schedule–Integrated Overall Time Schedule (IOTS)is the contract schedule for the Contractor (ASE JSC) and their subcontractors.The principal purpose of IOTS is the work progress planning and monitoring, the analysis of the effect of activities implementation upon the progress of the Project as a whole. IOTS is the reporting schedule at the Employer –Contractor level. Level 3 Schedules, Detail Time Schedules(DTS) are developed by those who actually perform the work and are agreed upon with Atomstroyexport JSC.The main purpose of DTS is the detail planning of Atomstroyexport subcontractor's activities. DTSare the reporting schedules at the level of Contractor-Subcontractor. Level 4 Schedules are the High Detail Time Schedules (HDTS), which are the day-to-day plans of work implementation and are developed, as a rule, for a week's time period.Each lower level time schedule details the activities of the higher level time schedule

Advanced maintenance research programs

International Nuclear Information System (INIS)

Marston, T.U.; Gelhaus, F.; Burke, R.

1985-01-01

The purpose of this paper is to provide the reader with an idea of the advanced maintenance research program at the Electric Power Research Institute (EPRI). A brief description of the maintenance-related activities is provided as a foundation for the advanced maintenance research projects. The projects can be divided into maintenance planning, preventive maintenance program development and implementation, predictive (or conditional) maintenance, and innovative maintenance techniques. The projects include hardware and software development, human factors considerations, and technology promotion and implementation. The advanced concepts include: the incorporation of artificial intelligence into outage planning; turbine and pump maintenance; rotating equipment monitoring and diagnostics with the aid of expert systems; and the development of mobile robots for nuclear power plant maintenance

Parents' Family Time and Work Schedules: The Split-Shift Schedule in Spain

NARCIS (Netherlands)

Gracia, P.; Kalmijn, M.

2016-01-01

This study used data on couples from the 2003 Spanish Time Use Survey (N = 1,416) to analyze how work schedules are associated with family, couple, parent–child, and non-family leisure activities. Spain is clearly an interesting case for the institutionalized split-shift schedule, a long lunch break

Maintenance Management Update.

Science.gov (United States)

Sternloff, Robert E.

1987-01-01

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

Analyzing scheduling in the food-processing industry

DEFF Research Database (Denmark)

Akkerman, Renzo; van Donk, Dirk Pieter

2009-01-01

Production scheduling has been widely studied in several research areas, resulting in a large number of methods, prescriptions, and approaches. However, the impact on scheduling practice seems relatively low. This is also the case in the food-processing industry, where industry......-specific characteristics induce specific and complex scheduling problems. Based on ideas about decomposition of the scheduling task and the production process, we develop an analysis methodology for scheduling problems in food processing. This combines an analysis of structural (technological) elements of the production...... process with an analysis of the tasks of the scheduler. This helps to understand, describe, and structure scheduling problems in food processing, and forms a basis for improving scheduling and applying methods developed in literature. It also helps in evaluating the organisational structures...

Future aircraft networks and schedules

Science.gov (United States)

Shu, Yan

2011-07-01

Because of the importance of air transportation scheduling, the emergence of small aircraft and the vision of future fuel-efficient aircraft, this thesis has focused on the study of aircraft scheduling and network design involving multiple types of aircraft and flight services. It develops models and solution algorithms for the schedule design problem and analyzes the computational results. First, based on the current development of small aircraft and on-demand flight services, this thesis expands a business model for integrating on-demand flight services with the traditional scheduled flight services. This thesis proposes a three-step approach to the design of aircraft schedules and networks from scratch under the model. In the first step, both a frequency assignment model for scheduled flights that incorporates a passenger path choice model and a frequency assignment model for on-demand flights that incorporates a passenger mode choice model are created. In the second step, a rough fleet assignment model that determines a set of flight legs, each of which is assigned an aircraft type and a rough departure time is constructed. In the third step, a timetable model that determines an exact departure time for each flight leg is developed. Based on the models proposed in the three steps, this thesis creates schedule design instances that involve almost all the major airports and markets in the United States. The instances of the frequency assignment model created in this thesis are large-scale non-convex mixed-integer programming problems, and this dissertation develops an overall network structure and proposes iterative algorithms for solving these instances. The instances of both the rough fleet assignment model and the timetable model created in this thesis are large-scale mixed-integer programming problems, and this dissertation develops subproblem schemes for solving these instances. Based on these solution algorithms, this dissertation also presents

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.

Range Scheduling Aid (RSA)

Science.gov (United States)

Logan, J. R.; Pulvermacher, M. K.

1991-01-01

Range Scheduling Aid (RSA) is presented in the form of the viewgraphs. The following subject areas are covered: satellite control network; current and new approaches to range scheduling; MITRE tasking; RSA features; RSA display; constraint based analytic capability; RSA architecture; and RSA benefits.

Immunization Schedules for Infants and Children

Science.gov (United States)

... ACIP Vaccination Recommendations Why Immunize? Vaccines: The Basics Immunization Schedule for Infants and Children (Birth through 6 ... any questions please talk to your doctor. 2018 Immunization Schedule Recommended Vaccinations for Infants and Children Schedule ...

ELEMENTS OF MAINTENANCE MANAGEMENT IN PUBLIC INSTITUTIONS OF HIGHER EDUCATION CABIMAS MUNICIPALITY

Directory of Open Access Journals (Sweden)

Ricardo Castillo

2013-07-01

Full Text Available This article is an advance of a wider investigation, in which the objective is to analyze overall maintenance management in public institutions of higher education in the municipality Cabimas, hence in this development describes the elements of the management maintenance present in these institutions. Authors were consulted such as Duffuaa et al. (2010, Clemenza (2010, Zambrano and Leal (2006 , Robbins and Coulter (2005 y Martínez (2007 among others. The research is descriptive, non-experimental   design, transactional  and  field.  We  used  a population   census,  for  a  total  of   twenty-three  (23   research  subjects,  belonging  to  the Universidad   del   Zulia    Núcleo   Costa   Oriental   del   Lago,  Universidad    Nacional Experimental  Rafael  Maria Baralt and  Instituto Universitario Tecnológico  Cabimas. To collect data, a questionnaire was composed of twenty-two (22 items, which was validated by the trial of six (6 experts, with 0.99 reliability by Cronbach alpha coefficient.  We conclude that the elements planning, organizing, scheduling, execution and control, have a high presence in maintenance management, not the human resource and security elements.

A Formal Product-Line Engineering Approach for Schedulers

NARCIS (Netherlands)

Orhan, Güner; Aksit, Mehmet; Rensink, Arend; Jololian, Leon; Robbins, David E.; Fernandes, Steven L.

2017-01-01

Scheduling techniques have been applied to a large category of software systems, such as, processor scheduling in operating systems, car scheduling in elevator systems, facility scheduling at airports, antenna scheduling in radar systems, scheduling of events, control signals and data in

Robust and Flexible Scheduling with Evolutionary Computation

DEFF Research Database (Denmark)

Jensen, Mikkel T.

Over the last ten years, there have been numerous applications of evolutionary algorithms to a variety of scheduling problems. Like most other research on heuristic scheduling, the primary aim of the research has been on deterministic formulations of the problems. This is in contrast to real world...... scheduling problems which are usually not deterministic. Usually at the time the schedule is made some information about the problem and processing environment is available, but this information is uncertain and likely to change during schedule execution. Changes frequently encountered in scheduling...... environments include machine breakdowns, uncertain processing times, workers getting sick, materials being delayed and the appearance of new jobs. These possible environmental changes mean that a schedule which was optimal for the information available at the time of scheduling can end up being highly...

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

International Nuclear Information System (INIS)

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

1999-01-01

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

The development of KMRR schedule and progress control system (KSPCS) for the master schedule of KMRR project

International Nuclear Information System (INIS)

Choi, Chang Woong; Lee, Tae Joon; Kim, Joon Yun; Cho, Yun Ho; Hah, Jong Hyun

1993-07-01

This report was to development the computerized schedule and progress control system for the master schedule of KMRR project with ARTEMIS 7000/386 CM (Ver. 7.4.2.) based on project management theory (PERT/CPM, PDM, and S-curve). This system has been efficiently used for KMRR master schedule and will be utilized for the detail scheduling of KMRR project. (Author) 23 refs., 26 figs., 52 tabs

The development of KMRR schedule and progress control system (KSPCS) for the master schedule of KMRR project

Energy Technology Data Exchange (ETDEWEB)

Choi, Chang Woong; Lee, Tae Joon; Kim, Joon Yun; Cho, Yun Ho; Hah, Jong Hyun [Korea Atomic Energy Research Institute, Taejon (Korea, Republic of)

1993-07-01

This report was to development the computerized schedule and progress control system for the master schedule of KMRR project with ARTEMIS 7000/386 CM (Ver. 7.4.2.) based on project management theory (PERT/CPM, PDM, and S-curve). This system has been efficiently used for KMRR master schedule and will be utilized for the detail scheduling of KMRR project. (Author) 23 refs., 26 figs., 52 tabs.

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

International Nuclear Information System (INIS)

Angelevska, Silvana; Jolevski, Tome

2000-01-01

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

Assessing maintenance contracts when preventive maintenance is outsourced

International Nuclear Information System (INIS)

Wu Shaomin

2012-01-01

In some companies, corrective maintenance is conducted in-house but preventive maintenance might be outsourced. This raises a need to optimise some parameters such as the number of contracts from a perspective of the equipment owner. This paper considers a maintenance policy for such a situation, analyses the roles of the parameters in a PM model, proposes approaches to defining bonus functions, and finally discusses special cases of both the PM policy and the bonus function. Numerical examples are also given to explore the impact of parameters on the expected lifecycle cost rate.

78 FR 21818 - Schedules of Controlled Substances: Placement of Methylone Into Schedule I

Science.gov (United States)

2013-04-12

..., methamphetamine, and MDMA, Schedule I and II substances. These effects included elevated body temperature... of reuptake of monoamines, and in vivo studies (microdialysis, locomotor activity, body temperature.... Yet another commenter claimed that Schedule I placement would ``cripple efforts at learning,'' make it...

Maintenance Of The EPS 3000 Electron Beam Machine As Part Of Quality Assurance Program For Irradiation Service At ALURTRON, Nuclear Malaysia

International Nuclear Information System (INIS)

Siti Aiasah Hashim; Shari Jahar; Ayub Muhammad; Azmi Ali; Abdul Basit Shafiei; Sarada Idris

2012-01-01

The EPS 3000 electron beam machine is the first of its kind in the country and was installed in Nuclear Malaysia in 1991. It was manufactured by Nissin High Voltage having variable energies from 0.5 to 3.0 MeV and maximum power of 90 kW. The machine is currently used for commercial irradiation that serves local industries. The Alurtron facility where the EPS is housed is an ISO 9000 certified plant. Maintenance program for the EPS is an essential part of Alurtron's Quality Assurance program. This is to ensure that the machine is in good condition and can serve the customer as the demand requires. Preventive maintenance is carried out at scheduled period based on recommendation of the machine's manufacturer. Corrective maintenance and repairs are carried out in-house by Alurtron's technical staff. Assistance may be sought from the manufacturer if necessary. Over the years, Alurtron had built its own capabilities in term of operation and maintenance of Cockcroft Walton type electron beam machine. (author)

Managing nuclear maintenance

International Nuclear Information System (INIS)

Anon.

1990-01-01

For utilities operating nuclear powerplants, the rules of the game continue to change. Conflicting regulatory pressures and a tougher competitive environment will make management's job more complicated and difficult in the 1990s. Dealing with these pressures successfully requires greater attention to maintenance effectiveness. Utilities can help shape their future environment by developing a well-planned strategy to guide their actions. Parts of the strategy that are discussed include developing a sound maintenance philosophy, selecting a service company, radiation exposure, and managing spare parts. This article also addresses the Swedish experience in maintenance, German philosophy regarding maintenance and the current maintenance practices of the Electricite de France

AIRCRAFT MAINTENANCE HANGAR

Directory of Open Access Journals (Sweden)

GEAMBASU Gabriel George

2017-05-01

Full Text Available The paper presents the maintenance process that is done on an airplane, at a certain period of time, or after a number of flight hours or cycles and describes the checks performed behind each inspection. The first part of research describes the aircraft maintenance process that has to be done after an updated maintenance manual according with aircraft type, followed by a short introduction about maintenance hangar. The second part of the paper presents a hangar design with a foldable roof and walls, which can be folded or extended, over an airplane when a maintenance process is done, or depending on weather condition.

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…

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

International Nuclear Information System (INIS)

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

2003-01-01

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

Decentralized Ground Staff Scheduling

DEFF Research Database (Denmark)

Sørensen, M. D.; Clausen, Jens

2002-01-01

scheduling is investigated. The airport terminal is divided into zones, where each zone consists of a set of stands geographically next to each other. Staff is assigned to work in only one zone and the staff scheduling is planned decentralized for each zone. The advantage of this approach is that the staff...... work in a smaller area of the terminal and thus spends less time walking between stands. When planning decentralized the allocation of stands to flights influences the staff scheduling since the workload in a zone depends on which flights are allocated to stands in the zone. Hence solving the problem...... depends on the actual stand allocation but also on the number of zones and the layout of these. A mathematical model of the problem is proposed, which integrates the stand allocation and the staff scheduling. A heuristic solution method is developed and applied on a real case from British Airways, London...

Schedule control in Ling Ao nuclear power project

International Nuclear Information System (INIS)

Xie Ahai

2007-01-01

Ling Ao Nuclear Power Station (LANP) is first one built up by self-reliance in China with power capacity 990x2 MWe. The results of quality control, schedule control and cost control are satisfactory. The commercial operation days of Unit 1 and Unit 2 were 28th May 2002 and 8th Jan. 2003 respectively, which were 48 days and 66 days in advance of the project schedule. This paper presents the practices of self-reliance schedule control system in LANP. The paper includes 10 sections: schedule control system; targets of schedule control; schedule control at early stage of project; construction schedule; scheduling practice; Point curves; schedule control of design and procurement; a good practice of construction schedule control on site; commissioning and startup schedule; schedule control culture. Three figures are attached. The main contents of the self-reliance schedule control system are as follows: to draw up reasonable schedules and targets; to setup management mechanism and procedures; to organize powerful project management team; to establish close monitoring system; to provide timely progress reports and statistics information. Five kinds of schedule control targets are introduced, i.e. bar-chart schedule; milesones; Point curves; interface management; hydraulic test schedule of auxiliary piping loops; EMR/EMC/EESR issuance schedules. Six levels of bar-chart schedules were adopted in LANP, but the bar-chart schedules were not satisfactory for complicated erection condition on site, even using six levels of schedules. So a kind of Point curves was developed and their advantages are explained. Scheduling method of three elements: activity, duration, logic, which was adopted in LANP, is introduced. The duration of each piping activities in LANP level 2 project schedule was calculated based on the relevant working Point quantities. The analysis and adjustment of Point curves are illustrated, i.e. balance of monthly quantities; possible production in the peakload

Multiuser switched diversity scheduling schemes

KAUST Repository

Shaqfeh, Mohammad; Alnuweiri, Hussein M.; Alouini, Mohamed-Slim

2012-01-01

Multiuser switched-diversity scheduling schemes were recently proposed in order to overcome the heavy feedback requirements of conventional opportunistic scheduling schemes by applying a threshold-based, distributed, and ordered scheduling mechanism. The main idea behind these schemes is that slight reduction in the prospected multiuser diversity gains is an acceptable trade-off for great savings in terms of required channel-state-information feedback messages. In this work, we characterize the achievable rate region of multiuser switched diversity systems and compare it with the rate region of full feedback multiuser diversity systems. We propose also a novel proportional fair multiuser switched-based scheduling scheme and we demonstrate that it can be optimized using a practical and distributed method to obtain the feedback thresholds. We finally demonstrate by numerical examples that switched-diversity scheduling schemes operate within 0.3 bits/sec/Hz from the ultimate network capacity of full feedback systems in Rayleigh fading conditions. © 2012 IEEE.

Multiuser switched diversity scheduling schemes

KAUST Repository

Shaqfeh, Mohammad

2012-09-01

Multiuser switched-diversity scheduling schemes were recently proposed in order to overcome the heavy feedback requirements of conventional opportunistic scheduling schemes by applying a threshold-based, distributed, and ordered scheduling mechanism. The main idea behind these schemes is that slight reduction in the prospected multiuser diversity gains is an acceptable trade-off for great savings in terms of required channel-state-information feedback messages. In this work, we characterize the achievable rate region of multiuser switched diversity systems and compare it with the rate region of full feedback multiuser diversity systems. We propose also a novel proportional fair multiuser switched-based scheduling scheme and we demonstrate that it can be optimized using a practical and distributed method to obtain the feedback thresholds. We finally demonstrate by numerical examples that switched-diversity scheduling schemes operate within 0.3 bits/sec/Hz from the ultimate network capacity of full feedback systems in Rayleigh fading conditions. © 2012 IEEE.

NASA Instrument Cost/Schedule Model

Science.gov (United States)

Habib-Agahi, Hamid; Mrozinski, Joe; Fox, George

2011-01-01

NASA's Office of Independent Program and Cost Evaluation (IPCE) has established a number of initiatives to improve its cost and schedule estimating capabilities. 12One of these initiatives has resulted in the JPL developed NASA Instrument Cost Model. NICM is a cost and schedule estimator that contains: A system level cost estimation tool; a subsystem level cost estimation tool; a database of cost and technical parameters of over 140 previously flown remote sensing and in-situ instruments; a schedule estimator; a set of rules to estimate cost and schedule by life cycle phases (B/C/D); and a novel tool for developing joint probability distributions for cost and schedule risk (Joint Confidence Level (JCL)). This paper describes the development and use of NICM, including the data normalization processes, data mining methods (cluster analysis, principal components analysis, regression analysis and bootstrap cross validation), the estimating equations themselves and a demonstration of the NICM tool suite.

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

Directory of Open Access Journals (Sweden)

Shima MohammadZadeh Dogahe

2015-01-01

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

Optimizing the Steel Plate Storage Yard Crane Scheduling Problem Using a Two Stage Planning/Scheduling Approach

DEFF Research Database (Denmark)

Hansen, Anders Dohn; Clausen, Jens

This paper presents the Steel Plate Storage Yard Crane Scheduling Problem. The task is to generate a schedule for two gantry cranes sharing tracks. The schedule must comply with a number of constraints and at the same time be cost efficient. We propose some ideas for a two stage planning...

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

The triangle scheduling problem

NARCIS (Netherlands)

Dürr, Christoph; Hanzálek, Zdeněk; Konrad, Christian; Seddik, Yasmina; Sitters, R.A.; Vásquez, Óscar C.; Woeginger, Gerhard

2017-01-01

This paper introduces a novel scheduling problem, where jobs occupy a triangular shape on the time line. This problem is motivated by scheduling jobs with different criticality levels. A measure is introduced, namely the binary tree ratio. It is shown that the Greedy algorithm solves the problem to

Competence within Maintenance

OpenAIRE

Nerland, Annette Smørholm

2010-01-01

Maintenance can be a contributing factor to unwanted events, as well as desired events and states. Human competence can be defined as the ability to perform a specific task, action or function successfully, and is therefore a key factor to proper execution of maintenance tasks. Hence,maintenance will have negative consequences if done wrong, and give positive results when done right. The purpose of this report is to study the many aspects of maintenance competence. Endeavoring to improve ...

A System for Automatically Generating Scheduling Heuristics

Science.gov (United States)

Morris, Robert

1996-01-01

The goal of this research is to improve the performance of automated schedulers by designing and implementing an algorithm by automatically generating heuristics by selecting a schedule. The particular application selected by applying this method solves the problem of scheduling telescope observations, and is called the Associate Principal Astronomer. The input to the APA scheduler is a set of observation requests submitted by one or more astronomers. Each observation request specifies an observation program as well as scheduling constraints and preferences associated with the program. The scheduler employs greedy heuristic search to synthesize a schedule that satisfies all hard constraints of the domain and achieves a good score with respect to soft constraints expressed as an objective function established by an astronomer-user.

Applying dynamic priority scheduling scheme to static systems of pinwheel task model in power-aware scheduling.

Science.gov (United States)

Seol, Ye-In; Kim, Young-Kuk

2014-01-01

Power-aware scheduling reduces CPU energy consumption in hard real-time systems through dynamic voltage scaling (DVS). In this paper, we deal with pinwheel task model which is known as static and predictable task model and could be applied to various embedded or ubiquitous systems. In pinwheel task model, each task's priority is static and its execution sequence could be predetermined. There have been many static approaches to power-aware scheduling in pinwheel task model. But, in this paper, we will show that the dynamic priority scheduling results in power-aware scheduling could be applied to pinwheel task model. This method is more effective than adopting the previous static priority scheduling methods in saving energy consumption and, for the system being still static, it is more tractable and applicable to small sized embedded or ubiquitous computing. Also, we introduce a novel power-aware scheduling algorithm which exploits all slacks under preemptive earliest-deadline first scheduling which is optimal in uniprocessor system. The dynamic priority method presented in this paper could be applied directly to static systems of pinwheel task model. The simulation results show that the proposed algorithm with the algorithmic complexity of O(n) reduces the energy consumption by 10-80% over the existing algorithms.

Health and maintenance outages in nuclear power plants: an epidemiological survey

International Nuclear Information System (INIS)

Telle, M.A.; Huez, D.; Niedbala, J.M.; Auclair, J.; Canales, J.P.; Duverge, C.; Forest, H.; Gerondal, M.; Paris, P.M.; Renault, J.C.; Bossevain, L.; Blaise, P.; Blanc, M.C.; Goldberg, M.; Charpak, Y.

1995-01-01

An epidemiological survey, started in 1989, was carried out at the nuclear power plants in the Loire river valley and at Le Blayais (France). Working conditions, work organisation and their impact on health during annual maintenance outages were studied. The main areas covered in this cross-sectional study were: anxiety and symptoms of depression using the Spielberger and CES-D scales. Comparisons were made during both a scheduled outage and in normal operation on four distinct groups of workers, each individual being his own control. A chi-square test was used for the quantitative variables and a test on differences for the quantitative variables. During a unit outage, more frequent overtime and atypical working hours were reported (p<0.01); working rhythms and safety rules were felt as more restrictive and exposure to radiation higher (p<0.01). Detrimental modifications of anxiety and symptoms of depression were observed on controllers whereas expected on maintenance agents. Similar results were observed when considering the rates of outages. Possible readings are given with reference to qualitative studies carried out on this topic, which implies extending our research with both the quantitative and qualitative approaches. (authors). 10 refs., 6 tabs

Plant Maintenance. The Licensee's Viewpoint

Energy Technology Data Exchange (ETDEWEB)

Ungi, T. [Heysham 2 Power Station, Nuclear Electric LTD (United Kingdom)

1997-07-01

Plant maintenance is a very complex process which requires considerable effort from both within the maintenance process and also many support activities. It is important that the plant maintenance policy is translated into a maintenance programme which will define all relevant aspects of the maintenance. An aspect of this maintenance programme will be a maintenance catalogue which will define the maintenance activities to be carried out and at what frequencies. This paper is aimed at discussing the maintenance philosophy and resulting maintenance catalogues currently adopted in Nuclear Electric Ltd, and in particular at Heysham 2 Power Station. It goes on to consider whether these maintenance catalogues contain the optimum maintenance and if not should they be changed. If change is required, the process by which this change will be brought about is also discussed. (author)

Lean Maintenance Applied to Improve Maintenance Efficiency in Thermoelectric Power Plants

OpenAIRE

Orlando Duran; Andrea Capaldo; Paulo Andrés Duran Acevedo

2017-01-01

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

Works scheduling. Warranting the availability of your facilities is one of our daily challenge. Scheduling our works with you favors this availability; Programmation des travaux. Garantir la disponibilite de vos installations constitue l'un de nos defis quotidiens. Programmer nos travaux avec vous favorise cette disponibilite

Energy Technology Data Exchange (ETDEWEB)

NONE

2001-12-01

One of the missions of the French manager of the power transportation grid (RTE) is to maintain and improve the performance of the network in order to warrant the security and quality of power supplies. Thus, any maintenance or development works leading to the unavailableness of the client's power connection requires a precise scheduling of these works. The aim of this brochure is to describe the procedure to follow in this case. (J.S.)

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)

Artificial intelligence approaches to astronomical observation scheduling

Science.gov (United States)

Johnston, Mark D.; Miller, Glenn

1988-01-01

Automated scheduling will play an increasing role in future ground- and space-based observatory operations. Due to the complexity of the problem, artificial intelligence technology currently offers the greatest potential for the development of scheduling tools with sufficient power and flexibility to handle realistic scheduling situations. Summarized here are the main features of the observatory scheduling problem, how artificial intelligence (AI) techniques can be applied, and recent progress in AI scheduling for Hubble Space Telescope.

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

Science.gov (United States)

Sezdi, Mana

2016-01-01

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

Modular robotic applications in nuclear power plant maintenance

International Nuclear Information System (INIS)

Glass, S.W.; Ranson, C.C.; Reinholtz, C.F.; Calkins, J.M.

1996-01-01

General-purpose factory automation robots have experienced limited use in nuclear maintenance and hazardous-environment work spaces due to demanding requirements on size, weight, mobility and adaptability. Robotic systems in nuclear power plants are frequently custom designed to meet specific space and performance requirements. Examples of these custom configurations include Framatome Technologies COBRA trademark Steam Generator Manipulator and URSULA trademark Reactor Vessel Inspection Manipulator. The use of custom robots in nuclear plants has been limited because of the lead time and expense associated with custom design. Developments in modular robotics and advanced robot control software coupled with more powerful low-cost computers, however, are helping to reduce the cost and schedule for deploying custom robots. A modular robotic system allows custom robot configurations to be implemented using standard (modular) joints and adaptable controllers. This paper discusses Framatome Technologies (FTI) current and planned developments in the area of modular robot system design

Planning and scheduling - A schedule's performance

International Nuclear Information System (INIS)

Whitman, N.M.

1993-01-01

Planning and scheduling is a process whose time has come to PSI Energy. With an awareness of the challenges ahead, individuals must look for ways to enhance the corporate competitiveness. Working toward this goal means that each individual has to dedicate themselves to this more competitive corporate environment. Being competitive may be defined as the ability of each employee to add value to the corporation's economic well being. The timely and successful implementation of projects greatly enhances competitiveness. Those projects that do not do well often suffer from lack of proper execution - not for lack of talent or strategic vision. Projects are consumers of resources such as cash and people. They produce a return when completed and will generate a better return when properly completed utilizing proven project management techniques. Completing projects on time, within budget and meeting customer expectations is the way a corporation builds it's future. This paper offers suggestions on implementing planning and scheduling and provides a review of results in the form of management reports

Alternative Work Schedules: Definitions

Science.gov (United States)

Journal of the College and University Personnel Association, 1977

1977-01-01

The term "alternative work schedules" encompasses any variation of the requirement that all permanent employees in an organization or one shift of employees adhere to the same five-day, seven-to-eight-hour schedule. This article defines staggered hours, flexible working hours (flexitour and gliding time), compressed work week, the task system, and…

Planning and Scheduling of Airline Operations

Directory of Open Access Journals (Sweden)

İlkay ORHAN

2010-02-01

Full Text Available The Turkish Civil Aviation sector has grown at a rate of 53 % between the years 2002-2008 owing to countrywide economical developments and some removed restrictions in the aviation field. Successful international companies in the sector use advanced computer-supported solution methods for their planning and scheduling problems. These methods have been providing significant competitive advantages to those companies. There are four major scheduling and planning problems in the airline sector: flight scheduling, aircraft scheduling, crew scheduling and disruptions management. These aforementioned scheduling and planning problems faced by all airline companies in the airline sector were examined in detail. Studies reveal that companies using the advanced methods might gain significant cost reductions. However, even then, the time required for solving large scale problems may not satisfy the decision quality desired by decision makers. In such cases, using modern decision methods integrated with advanced technologies offer companies an opportunity for significant cost-advantages.

Development of Watch Schedule Using Rules Approach

Science.gov (United States)

Jurkevicius, Darius; Vasilecas, Olegas

The software for schedule creation and optimization solves a difficult, important and practical problem. The proposed solution is an online employee portal where administrator users can create and manage watch schedules and employee requests. Each employee can login with his/her own account and see his/her assignments, manage requests, etc. Employees set as administrators can perform the employee scheduling online, manage requests, etc. This scheduling software allows users not only to see the initial and optimized watch schedule in a simple and understandable form, but also to create special rules and criteria and input their business. The system using rules automatically will generate watch schedule.

Technology for planning and scheduling under complex constraints

Science.gov (United States)

Alguire, Karen M.; Pedro Gomes, Carla O.

1997-02-01

Within the context of law enforcement, several problems fall into the category of planning and scheduling under constraints. Examples include resource and personnel scheduling, and court scheduling. In the case of court scheduling, a schedule must be generated considering available resources, e.g., court rooms and personnel. Additionally, there are constraints on individual court cases, e.g., temporal and spatial, and between different cases, e.g., precedence. Finally, there are overall objectives that the schedule should satisfy such as timely processing of cases and optimal use of court facilities. Manually generating a schedule that satisfies all of the constraints is a very time consuming task. As the number of court cases and constraints increases, this becomes increasingly harder to handle without the assistance of automatic scheduling techniques. This paper describes artificial intelligence (AI) technology that has been used to develop several high performance scheduling applications including a military transportation scheduler, a military in-theater airlift scheduler, and a nuclear power plant outage scheduler. We discuss possible law enforcement applications where we feel the same technology could provide long-term benefits to law enforcement agencies and their operations personnel.

Application of an integrated risk management system for improved maintenance in industrial plants

Energy Technology Data Exchange (ETDEWEB)

Jovanovic, A.; Balos, D.T.; Vinod, G.; Balos, D. [Steinbeis Advanced Risk Technologies, Stuttgart (Germany); Stanojevic, P. [NIS - Petroleum Industry of Serbia, Novi Sad (Serbia)

2007-06-15

The paper presents the application of the Integrated Risk Management System (iRiS) and its application to the areas of Risk Based Inspection (RBI), Reliability Centered Maintenance (RCM), Root Cause Failure Analysis (RCFA) and Health, Safety and Environment (HSE). The web-based system integrates also the aspects of risk management related to data acquisition and management and interactive reporting and controlled use of single parts of the system by various individual users and/or user levels. A complementing part of the system is a tool for project management including the documentation and activity management, as well as scheduling and e-education and e-training. The complementing parts of the system are the CMMS part (maintenance management), the extension of HSE to HSSE (including the 'security' aspects and providing links to the disaster management system) and further interfacing towards general management system and process modeling and management systems. Experiences from the applications of system in Hungary (at over 60 units) and in Serbia, for several refineries and further units in upstream and downstream, are presented in the paper. (orig.)

NRC comprehensive records disposition schedule

International Nuclear Information System (INIS)

1983-05-01

Effective January 1, 1982, NRC will institute records retention and disposal practives in accordance with the approved Comprehensive Records Disposition Schedule (CRDS). CRDS is comprised of NRC Schedules (NRCS) 1 to 4 which apply to the agency's program or substantive records and General Records Schedules (GRS) 1 to 24 which apply to housekeeping or facilitative records. NRCS-I applies to records common to all or most NRC offices; NRCS-II applies to program records as found in the various offices of the Commission, Atomic Safety and Licensing Board Panel, and the Atomic Safety and Licensing Appeal Panel; NRCS-III applies to records accumulated by the Advisory Committee on Reactor Safeguards; and NRCS-IV applies to records accumulated in the various NRC offices under the Executive Director for Operations. The schedules are assembled functionally/organizationally to facilitate their use. Preceding the records descriptions and disposition instructions for both NRCS and GRS, there are brief statements on the organizational units which accumulate the records in each functional area, and other information regarding the schedules' applicability

Integrated maintenance program (IMP)

International Nuclear Information System (INIS)

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

1998-01-01

Approaches to the maintenance of nuclear power plants have undergone significant change in the past several decades. The traditional breakdown approach has been displaced by preventive (calendar-based) maintenance and more recently, by condition-based maintenance (CBM). This is largely driven by the fact that traditional maintenance programs, derived primarily from equipment vendor recommendations, are generally unsuccessful in controlling maintenance costs or equipment failures. Many advances in the maintenance field have taken place since the maintenance plans for Ontario Hydro's nuclear plants were initially established. Ontario Hydro nuclear plant operating costs can be substantially reduced and Incapability Factor improved with the application of modern maintenance processes and tools. Pickering is designated as the lead station for IMP. Of immediate concern is the fact that Pickering Nuclear Division has been experiencing a significant backlog of Operating Preventive Maintenance Callups. This backlog, over 2000, is unacceptable to both station management and the nuclear regulator, the Atomic Energy Control Board. In addition there are over 500 callups in various stages of revision (in hyperspace) without an adequate control nor reporting system to manage their completion. There is also considerable confusion about the classification of l icensing c allups, e.g. callups which are mandatory as a result of legal requirements. Furthermore the ineffectiveness of the Preventive Maintenance (PM) has been the subject of peer audits and Atomic Energy Control Board (AECB) findings over the past several years. The current preventive maintenance ratio PM2 /(PM+CM3) at Pickering ND is less than 20%, due to the current high load of equipment breakdown. This past summer, an Independent Integrated Performance Assessment (IIPA) review at Ontario Hydro confirmed these concerns. Over the past several years, Ontario Hydro nuclear staff have evaluated several programs to improve

CMS multicore scheduling strategy

International Nuclear Information System (INIS)

Yzquierdo, Antonio Pérez-Calero; Hernández, Jose; Holzman, Burt; Majewski, Krista; McCrea, Alison

2014-01-01

In the next years, processor architectures based on much larger numbers of cores will be most likely the model to continue 'Moore's Law' style throughput gains. This not only results in many more jobs in parallel running the LHC Run 1 era monolithic applications, but also the memory requirements of these processes push the workernode architectures to the limit. One solution is parallelizing the application itself, through forking and memory sharing or through threaded frameworks. CMS is following all of these approaches and has a comprehensive strategy to schedule multicore jobs on the GRID based on the glideinWMS submission infrastructure. The main component of the scheduling strategy, a pilot-based model with dynamic partitioning of resources that allows the transition to multicore or whole-node scheduling without disallowing the use of single-core jobs, is described. This contribution also presents the experiences made with the proposed multicore scheduling schema and gives an outlook of further developments working towards the restart of the LHC in 2015.

Maintenance work management system

International Nuclear Information System (INIS)

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

2000-01-01

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

Maintenance Production Demand and Capacity Analysis of Third Maintenance Battalion

Science.gov (United States)

2017-12-01

Delivery T/E Table of Equipment TFSMS Total Force Structure Management System TFSP Total Force Structure Process TM Technical Manual T/O Table of...exercises each year, both on Okinawa and throughout the Pacific theater. When equipment requires maintenance beyond the organizational -level...demand was analyzed based on customer cycle time (i.e., time that equipment was in Third Maintenance Battalion custody), maintenance cycle time during

Data analysis with the DIANA meta-scheduling approach

International Nuclear Information System (INIS)

Anjum, A; McClatchey, R; Willers, I

2008-01-01

The concepts, design and evaluation of the Data Intensive and Network Aware (DIANA) meta-scheduling approach for solving the challenges of data analysis being faced by CERN experiments are discussed in this paper. Our results suggest that data analysis can be made robust by employing fault tolerant and decentralized meta-scheduling algorithms supported in our DIANA meta-scheduler. The DIANA meta-scheduler supports data intensive bulk scheduling, is network aware and follows a policy centric meta-scheduling. In this paper, we demonstrate that a decentralized and dynamic meta-scheduling approach is an effective strategy to cope with increasing numbers of users, jobs and datasets. We present 'quality of service' related statistics for physics analysis through the application of a policy centric fair-share scheduling model. The DIANA meta-schedulers create a peer-to-peer hierarchy of schedulers to accomplish resource management that changes with evolving loads and is dynamic and adapts to the volatile nature of the resources

Scheduling lessons learned from the Autonomous Power System

Science.gov (United States)

Ringer, Mark J.

1992-01-01

The Autonomous Power System (APS) project at NASA LeRC is designed to demonstrate the applications of integrated intelligent diagnosis, control, and scheduling techniques to space power distribution systems. The project consists of three elements: the Autonomous Power Expert System (APEX) for Fault Diagnosis, Isolation, and Recovery (FDIR); the Autonomous Intelligent Power Scheduler (AIPS) to efficiently assign activities start times and resources; and power hardware (Brassboard) to emulate a space-based power system. The AIPS scheduler was tested within the APS system. This scheduler is able to efficiently assign available power to the requesting activities and share this information with other software agents within the APS system in order to implement the generated schedule. The AIPS scheduler is also able to cooperatively recover from fault situations by rescheduling the affected loads on the Brassboard in conjunction with the APEX FDIR system. AIPS served as a learning tool and an initial scheduling testbed for the integration of FDIR and automated scheduling systems. Many lessons were learned from the AIPS scheduler and are now being integrated into a new scheduler called SCRAP (Scheduler for Continuous Resource Allocation and Planning). This paper will service three purposes: an overview of the AIPS implementation, lessons learned from the AIPS scheduler, and a brief section on how these lessons are being applied to the new SCRAP scheduler.

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....

Grounds Maintenance Equipment and Procedures. Building Maintenance. Module VI. Instructor's Guide.

Science.gov (United States)

Crank, Virgil

This curriculum guide, one of six modules keyed to the building maintenance competency profile developed by industry and education professionals, provides materials for two units on grounds maintenance equipment and procedures. The first unit deals with grounds maintenance equipment and includes the following lessons: safety; changing oil/filter…

Optimization of Hierarchically Scheduled Heterogeneous Embedded Systems

DEFF Research Database (Denmark)

Pop, Traian; Pop, Paul; Eles, Petru

2005-01-01

We present an approach to the analysis and optimization of heterogeneous distributed embedded systems. The systems are heterogeneous not only in terms of hardware components, but also in terms of communication protocols and scheduling policies. When several scheduling policies share a resource......, they are organized in a hierarchy. In this paper, we address design problems that are characteristic to such hierarchically scheduled systems: assignment of scheduling policies to tasks, mapping of tasks to hardware components, and the scheduling of the activities. We present algorithms for solving these problems....... Our heuristics are able to find schedulable implementations under limited resources, achieving an efficient utilization of the system. The developed algorithms are evaluated using extensive experiments and a real-life example....

Sport Tournament Automated Scheduling System

OpenAIRE

Raof R. A. A; Sudin S.; Mahrom N.; Rosli A. N. C

2018-01-01

The organizer of sport events often facing problems such as wrong calculations of marks and scores, as well as difficult to create a good and reliable schedule. Most of the time, the issues about the level of integrity of committee members and also issues about errors made by human came into the picture. Therefore, the development of sport tournament automated scheduling system is proposed. The system will be able to automatically generate the tournament schedule as well as automatically calc...

Site Maintenance Plan: Part 2, Site Maintenance Action Plan for FY 1994

Energy Technology Data Exchange (ETDEWEB)

Fisk, E.L.

1994-06-01

This Fiscal Year (FY) 1994 Site Maintenance Action Plan (SMAP) is Part II of the Site Maintenance Plan, and has been written by Westinghouse Hanford Company (WHC) to outline the requirements stated in DOE Order 4330.4B, Maintenance Management Program, Chapter 1, Paragraph 3.3.1. The SMAP provides an annual status of maintenance initiatives completed and planned, a summary of performance indicators, a summary of maintenance backlog, a listing of real property and capital equipment maintenance cost estimates that were used to create the FY 1996 infrastructure and maintenance budget input, and a listing of proposed line item and general plant projects. Additionally, assumptions for various Site programs are listed to bring the Site Maintenance Plan into focus with overall Site activities. The primary mission at Hanford is to clean up the Site. In this cleanup process WHC will provide scientific and technological expertise to meet global needs, and partnership with stakeholders in the region to develop regional economic diversification. Other missions at the Hanford Site include energy research and development, and waste management and disposal activities. Their primary mission has a 30-year projected life span and will direct the shutting down and cleanup of defense production facilities and the Fast Flux Test Facility. This long-term mission requires continuous maintenance and in many instances, replacement of existing basic infrastructure, support facilities, and utilities. Without adequate maintenance and capital funding these infrastructure, support facilities, and utilities will continue to deteriorate causing an increase in backlogged work.

Site Maintenance Plan: Part 2, Site Maintenance Action Plan for FY 1994

International Nuclear Information System (INIS)

Fisk, E.L.

1994-06-01

This Fiscal Year (FY) 1994 Site Maintenance Action Plan (SMAP) is Part II of the Site Maintenance Plan, and has been written by Westinghouse Hanford Company (WHC) to outline the requirements stated in DOE Order 4330.4B, Maintenance Management Program, Chapter 1, Paragraph 3.3.1. The SMAP provides an annual status of maintenance initiatives completed and planned, a summary of performance indicators, a summary of maintenance backlog, a listing of real property and capital equipment maintenance cost estimates that were used to create the FY 1996 infrastructure and maintenance budget input, and a listing of proposed line item and general plant projects. Additionally, assumptions for various Site programs are listed to bring the Site Maintenance Plan into focus with overall Site activities. The primary mission at Hanford is to clean up the Site. In this cleanup process WHC will provide scientific and technological expertise to meet global needs, and partnership with stakeholders in the region to develop regional economic diversification. Other missions at the Hanford Site include energy research and development, and waste management and disposal activities. Their primary mission has a 30-year projected life span and will direct the shutting down and cleanup of defense production facilities and the Fast Flux Test Facility. This long-term mission requires continuous maintenance and in many instances, replacement of existing basic infrastructure, support facilities, and utilities. Without adequate maintenance and capital funding these infrastructure, support facilities, and utilities will continue to deteriorate causing an increase in backlogged work

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.

40 CFR 141.702 - Sampling schedules.

Science.gov (United States)

2010-07-01

... serving at least 10,000 people must submit their sampling schedule for the initial round of source water... submitting the sampling schedule that EPA approves. (3) Systems serving fewer than 10,000 people must submit... analytical result for a scheduled sampling date due to equipment failure, loss of or damage to the sample...

Long-Term Maintenance Therapy Using Rituximab-Induced Continuous B-Cell Depletion in Patients with ANCA Vasculitis

Science.gov (United States)

Pendergraft, William F.; Cortazar, Frank B.; Wenger, Julia; Murphy, Andrew P.; Rhee, Eugene P.; Laliberte, Karen A.; Niles, John L.

2014-01-01

Background and objectives Remission in the majority of ANCA vasculitis patients is not sustained after a single course of rituximab, and risk of relapse warrants development of a successful strategy to ensure durable remission. Design, setting, participants, & measurements A retrospective analysis of ANCA vasculitis patients who underwent maintenance therapy using rituximab-induced continuous B-cell depletion for up to 7 years was performed. Maintenance therapy with rituximab was initiated after achieving remission or converting from other prior maintenance therapy. Continuous B-cell depletion was achieved in all patients by scheduled rituximab administration every 4 months. Disease activity, serologic parameters, adverse events, and survival were examined. Results In the study, 172 patients (mean age=60 years, 55% women, 57% myeloperoxidase–ANCA) treated from April of 2006 to March of 2013 underwent continuous B-cell depletion with rituximab. Median remission maintenance follow-up time was 2.1 years. Complete remission (Birmingham Vasculitis Activity Score [BVAS]=0) was achieved in all patients. Major relapse (BVAS≥3) occurred in 5% of patients and was associated with weaning of other immunosuppression drugs. Remission was reinduced in all patients. Survival mirrored survival of a general age-, sex-, and ethnicity-matched United States population. Conclusion This analysis provides evidence for long-term disease control using continuous B-cell depletion. This treatment strategy in ANCA vasculitis patients also seems to result in survival rates comparable with rates in a matched reference population. These findings suggest that prospective remission maintenance treatment trials using continuous B-cell depletion are warranted. PMID:24626432

Prevalence of α(+)-Thalassemia in the Scheduled Tribe and Scheduled Caste Populations of Damoh District in Madhya Pradesh, Central India.

Science.gov (United States)

Singh, Mendi P S S; Gupta, Rasik B; Yadav, Rajiv; Sharma, Ravendra K; Shanmugam, Rajasubramaniam

2016-08-01

This study was carried out to ascertain the allelic frequency of α(+)-thalassemia (α(+)-thal) in Scheduled caste and scheduled tribe populations of the Damoh district of Madhya Pradesh, India. Random blood samples of Scheduled tribe (267) and Scheduled caste (168), considering the family as a sampling unit, were analyzed for the presence of the -α(3.7) (rightward) (NG_000006.1: g.34164_37967del3804) and -α(4.2) (leftward) (AF221717) deletions. α(+)-Thal was significantly higher in the Scheduled tribals (77.9%) as compared to the scheduled caste population (9.0%). About 58.0% scheduled tribals carried at least one chromosome with the -α(3.7) deletion and 20.0% scheduled tribals carried the -α(4.2) deletion. Frequency for the -α(3.7) allele was 0.487 in the scheduled tribal populations in comparison to 0.021 in scheduled castes. Allelic frequency for -α(4.2) was 0.103 and 0.024, respectively, in the above communities. No Hardy-Weinberg equilibrium for α-thal gene (p population, indicating the presence of selection pressures in favor of α-thal mutation and adaptation.

Routine environmental monitoring schedule, calendar year 1995

International Nuclear Information System (INIS)

Schmidt, J.W.; Markes, B.M.; McKinney, S.M.

1994-12-01

This document provides Bechtel Hanford, Inc. (BHI) and Westinghouse Hanford Company (WHC) a schedule of monitoring and sampling routines for the Operational Environmental Monitoring (OEM) program during calendar year (CY) 1995. Every attempt will be made to consistently follow this schedule; any deviation from this schedule will be documented by an internal memorandum (DSI) explaining the reason for the deviation. The DSI will be issued by the scheduled performing organization and directed to Near-Field Monitoring. The survey frequencies for particular sites are determined by the technical judgment of Near-Field Monitoring and may depend on the site history, radiological status, use and general conditions. Additional surveys may be requested at irregular frequencies if conditions warrant. All radioactive wastes sites are scheduled to be surveyed at least annually. Any newly discovered wastes sites not documented by this schedule will be included in the revised schedule for CY 1995

Inspection maintenance and planning of shutdown in thermal electric generating plants

International Nuclear Information System (INIS)

Dezordi, W.L.; Correa, D.A.; Kina, M.

1984-01-01

The schedule shutdown of an industrial plant and, more specifically, of an electrical generating station, is becoming increasingly important. The major parameters to be taken into account for the planning of such a shutdown are basically of economic-financial nature such as costs of the related services (materials, equipment, manpower, etc), loss of revenue caused by the station's shutdown as well as by the station availability, and other requirements expected from it by the Load Dispatch and consumers. Improving the equipment's performances and the station's availability are the fundamental objectives to be strived for. The authors present in this paper, in an abridged form, the planning tools used for thermal electric generating plants shutdowns for inspections, maintenance and design changes implementation. (Author) [pt

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.

Interactive Dynamic Mission Scheduling for ASCA

Science.gov (United States)

Antunes, A.; Nagase, F.; Isobe, T.

The Japanese X-ray astronomy satellite ASCA (Advanced Satellite for Cosmology and Astrophysics) mission requires scheduling for each 6-month observation phase, further broken down into weekly schedules at a few minutes resolution. Two tools, SPIKE and NEEDLE, written in Lisp and C, use artificial intelligence (AI) techniques combined with a graphic user interface for fast creation and alteration of mission schedules. These programs consider viewing and satellite attitude constraints as well as observer-requested criteria and present an optimized set of solutions for review by the planner. Six-month schedules at 1 day resolution are created for an oversubscribed set of targets by the SPIKE software, originally written for HST and presently being adapted for EUVE, XTE and AXAF. The NEEDLE code creates weekly schedules at 1 min resolution using in-house orbital routines and creates output for processing by the command generation software. Schedule creation on both the long- and short-term scale is rapid, less than 1 day for long-term, and one hour for short-term.

Automated scheduling and planning from theory to practice

CERN Document Server

Ozcan, Ender; Urquhart, Neil

2013-01-01

  Solving scheduling problems has long presented a challenge for computer scientists and operations researchers. The field continues to expand as researchers and practitioners examine ever more challenging problems and develop automated methods capable of solving them. This book provides 11 case studies in automated scheduling, submitted by leading researchers from across the world. Each case study examines a challenging real-world problem by analysing the problem in detail before investigating how the problem may be solved using state of the art techniques.The areas covered include aircraft scheduling, microprocessor instruction scheduling, sports fixture scheduling, exam scheduling, personnel scheduling and production scheduling.  Problem solving methodologies covered include exact as well as (meta)heuristic approaches, such as local search techniques, linear programming, genetic algorithms and ant colony optimisation.The field of automated scheduling has the potential to impact many aspects of our lives...

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

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

Predicting maintenance of attendance at walking groups: testing constructs from three leading maintenance theories.

Science.gov (United States)

Kassavou, Aikaterini; Turner, Andrew; Hamborg, Thomas; French, David P

2014-07-01

Little is known about the processes and factors that account for maintenance, with several theories existing that have not been subject to many empirical tests. The aim of this study was to test how well theoretical constructs derived from the Health Action Process Approach, Rothman's theory of maintenance, and Verplanken's approach to habitual behavior predicted maintenance of attendance at walking groups. 114 participants, who had already attended walking groups in the community for at least 3 months, completed a questionnaire assessing theoretical constructs regarding maintenance. An objective assessment of attendance over the subsequent 3 months was gained. Multilevel modeling was used to predict maintenance, controlling for clustering within walking groups. Recovery self-efficacy predicted maintenance, even after accounting for clustering. Satisfaction with social outcomes, satisfaction with health outcomes, and overall satisfaction predicted maintenance, but only satisfaction with health outcomes significantly predicted maintenance after accounting for clustering. Self-reported habitual behavior did not predict maintenance despite mean previous attendance being 20.7 months. Recovery self-efficacy, and satisfaction with health outcomes of walking group attendance appeared to be important for objectively measured maintenance, whereas self-reported habit appeared not to be important for maintenance at walking groups. The findings suggest that there is a need for intervention studies to boost recovery self-efficacy and satisfaction with outcomes of walking group attendance, to assess impact on maintenance.

Modeling Optimal Scheduling for Pumping System to Minimize Operation Cost and Enhance Operation Reliability

Directory of Open Access Journals (Sweden)

Yin Luo

2012-01-01

Full Text Available Traditional pump scheduling models neglect the operation reliability which directly relates with the unscheduled maintenance cost and the wear cost during the operation. Just for this, based on the assumption that the vibration directly relates with the operation reliability and the degree of wear, it could express the operation reliability as the normalization of the vibration level. The characteristic of the vibration with the operation point was studied, it could be concluded that idealized flow versus vibration plot should be a distinct bathtub shape. There is a narrow sweet spot (80 to 100 percent BEP to obtain low vibration levels in this shape, and the vibration also follows similar law with the square of the rotation speed without resonance phenomena. Then, the operation reliability could be modeled as the function of the capacity and rotation speed of the pump and add this function to the traditional model to form the new. And contrast with the tradition method, the result shown that the new model could fix the result produced by the traditional, make the pump operate in low vibration, then the operation reliability could increase and the maintenance cost could decrease.

PRACTICAL IMPLICATIONS OF LOCATION-BASED SCHEDULING

DEFF Research Database (Denmark)

Andersson, Niclas; Christensen, Knud

2007-01-01

The traditional method for planning, scheduling and controlling activities and resources in construction projects is the CPM-scheduling, which has been the predominant scheduling method since its introduction in the late 1950s. Over the years, CPM has proven to be a very powerful technique...... that will be used in this study. LBS is a scheduling method that rests upon the theories of line-of-balance and which uses the graphic representation of a flowline chart. As such, LBS is adapted for planning and management of workflows and, thus, may provide a solution to the identified shortcomings of CPM. Even...

Environmental surveillance master sampling schedule

International Nuclear Information System (INIS)

Bisping, L.E.

1991-01-01

Environmental surveillance of the Hanford Site and surrounding areas is conducted by the Pacific Northwest Laboratory (PNL) for the US Department of Energy (DOE). This document contains the planned schedule for routine sample collection for the Surface Environmental Surveillance Project (SESP) and Ground-Water Monitoring Project. The routine sampling plan for the SESP has been revised this year to reflect changing site operations and priorities. Some sampling previously performed at least annually has been reduced in frequency, and some new sampling to be performed at a less than annual frequency has been added. Therefore, the SESP schedule reflects sampling to be conducted in calendar year 1991 as well as future years. The ground-water sampling schedule is for 1991. This schedule is subject to modification during the year in response to changes in Site operation, program requirements, and the nature of the observed results. Operational limitations such as weather, mechanical failures, sample availability, etc., may also require schedule modifications. Changes will be documented in the respective project files, but this plan will not be reissued. The purpose of these monitoring projects is to evaluate levels of radioactive and nonradioactive pollutants in the Hanford evirons