The effects of stress on nuclear power plant operational decision making and training approaches to reduce stress effects

International Nuclear Information System (INIS)

Mumaw, R.J.

1994-08-01

Operational personnel may be exposed to significant levels of stress during unexpected changes in plant state an plant emergencies. The decision making that identifies operational actions, which is strongly determined by procedures, may be affected by stress, and performance may be impaired. ER report analyzes potential effects of stress in nuclear power plant (NPP) settings, especially in the context of severe accident management (SAM). First, potential sources of stress in the NPP setting are identified. This analysis is followed by a review of the ways in which stress is likely to affect performance, with an emphasis on performance of cognitive skills that are linked to operational decision making. Finally, potential training approaches for reducing or eliminating stress effects are identified. Several training approaches have the potential to eliminate or mitigate stress effects on cognitive skill performance. First, the use of simulated events for training can reduce the novelty and uncertainty that can lead to stress and performance impairments. Second, training to make cognitive processing more efficient and less reliant on attention and memory resources can offset the reductions in these resources that occur under stressful conditions. Third, training that targets crew communications skills can reduce the likelihood that communications will fail under stress

The effects of stress on nuclear power plant operational decision making and training approaches to reduce stress effects

Energy Technology Data Exchange (ETDEWEB)

Mumaw, R.J.

1994-08-01

Operational personnel may be exposed to significant levels of stress during unexpected changes in plant state an plant emergencies. The decision making that identifies operational actions, which is strongly determined by procedures, may be affected by stress, and performance may be impaired. ER report analyzes potential effects of stress in nuclear power plant (NPP) settings, especially in the context of severe accident management (SAM). First, potential sources of stress in the NPP setting are identified. This analysis is followed by a review of the ways in which stress is likely to affect performance, with an emphasis on performance of cognitive skills that are linked to operational decision making. Finally, potential training approaches for reducing or eliminating stress effects are identified. Several training approaches have the potential to eliminate or mitigate stress effects on cognitive skill performance. First, the use of simulated events for training can reduce the novelty and uncertainty that can lead to stress and performance impairments. Second, training to make cognitive processing more efficient and less reliant on attention and memory resources can offset the reductions in these resources that occur under stressful conditions. Third, training that targets crew communications skills can reduce the likelihood that communications will fail under stress.

Supporting plant operation through computer-based procedures

International Nuclear Information System (INIS)

Martinez, Victor; Medrano, Javier; Mendez, Julio

2014-01-01

Digital Systems are becoming more important in controlling and monitoring nuclear power plant operations. The capabilities of these systems provide additional functions as well as support operators in making decisions and avoiding errors. Regarding Operation Support Systems, an important way of taking advantage of these features is using computer-based procedures (CBPs) tools that enhance the plant operation. Integrating digital systems in analogue controls at nuclear power plants in operation becomes an extra challenge, in contrast to the integration of Digital Control Systems in new nuclear power plants. Considering the potential advantages of using this technology, Tecnatom has designed and developed a CBP platform taking currently operating nuclear power plants as its design basis. The result is a powerful tool which combines the advantages of CBPs and the conventional analogue control systems minimizing negative effects during plant operation and integrating operation aid-systems to support operators. (authors)

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

International Nuclear Information System (INIS)

Kitamura, Masaharu; Yoshikawa, Shinji; Hasegawa, Makoto

1998-03-01

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

Nuclear plant life - A business decision

International Nuclear Information System (INIS)

Joosten, J.K.

1995-01-01

Regarding the future of the nuclear power option, many scenarios have been put forth over the years. The most commonly accepted projections for installed nuclear capacity show it growing at a rate of about 2% per year throughout the next few decades. These projections appear modes on the surface. However, underlying the projections are critical assumptions and sometimes misconceptions about the lifetimes of existing reactors and how they are determined. The notion of a 40 year plant life is very common. Consequently, many projections start either with the assumption that no plants will be retired in the near terms or with the assumption that each retired plant will be replaced by another nuclear plant after 40 years. Effectively, these assumptions yield future projections for installed capacity that might be characterized as low growth, medium growth and high growth scenarios - or grow, grow, grow. The question remains as to whether or not these assumptions accurately model the driving forces and constraints to nuclear development. After all, there is no scientific basis for believing that all plants, PWRs BWRs, RBMKs, etc., should have the same 40 year life. Most power plant owners purchase the plant for the main reason of supplying electrical power to their consumer. For these owners, electricity production is a day to day commercial activity with various alternatives on how to achieve the prime objective. The decision of which electricity generation alternative to select (gas, coal, nuclear or renewable energy) and how long to operate the plant before replacing it with a new one is essentially a business decision. The paper discusses ageing, the nuclear plant life decision process, the factors which influence the decision and their ramifications regarding the near term growth of nuclear power capacity. The modelling of nuclear plant lifetimes is also discussed. (author). 5 refs, 10 figs, 1 tab

Superfund record of decision (EPA Region 3), Westinghouse Elevator Company Plant, Operable Unit 2, Cumberland Township, Adams County, Gettysburg, PA, March 31, 1995

Energy Technology Data Exchange (ETDEWEB)

NONE

1995-04-01

This Record of Decision (ROD) presents the selected remedial action for Operable Unit 2 (Soils) at the Westinghouse Elevator Company Plant Site in Adams County, Pennsylvania. The selected remedy for the soils at the Westinghouse Elevator Plant is No Additional Action for this Operable Unit. The other alternatives evaluated would produce little or no environmental benefit at substantial cost.

Manufacturers' support to plant operation

International Nuclear Information System (INIS)

Kuschel, D.

1996-01-01

For more than 30 years now, safety and availablity of German nuclear power plants has been a common interest of the plant owners and the manufacturing company KWU. This longstanding collaboration for a common goal has created a safety culture unprecented in other countries, and a partnership worth to be continued. Due to the nuclear power phaseout policy, the priority today is on maintaining and safeguarding economically efficient operation of existing power plants. KWU have been adapting their business strategy to the change in the market, and are prepared to stick to this line. Thus KWU and plant operators see to it that the acquired competence in nuclear power plant technology will remain to be concentrated in the hands of the manufacturers. Continuing the partnership in this field, and encouraged by the placement of orders for the future EPR and the SWR 1000, KWU and plant operators will be in the position to offer a sound option for future decisions about construction of new nuclear power plants in Germany. (orig.) [de

A Study on the Operator Decision Support for Feed-and-Bleed Operation

International Nuclear Information System (INIS)

Kim, Bo Gyung; Kim, Sang Ho; Kang, Hyun Gook; Yoon, Ho Joon

2014-01-01

In the case of a combined accident that includes a failure of the secondary cooling system, it is difficult for operators to recognize the necessity of an feed and bleed (F and B) operation because a lot of parameters and alarms should be checked before a decision, and operators may spend a considerable amount of time arriving at the entry for a proper emergency operating procedure that contains the procedure for an F and B operation. Therefore, a clear identification of the success boundary of an F and B operation would help operators in their decision-making when a combined accident that includes a secondary cooling system failure occurs. This study will provide a useful guideline for the initiation of an F and B operation for operators. Cooling the RCS after a scram is one of the most important safety functions for preventing core damage. To support the operator in decision making whether to initiate the F and B operation, plant conditions requiring the initiation of an F and B operation were identified. Plant conditions are affected by the steam generator inventory, RCS inventory, core inventory, and safety injection availability. The combination of accident types, component availabilities, and the initiation time of an F and B operation affect the success of the F and B operation. Operators need clear information about the RCS condition when the steam generators, the RCS's main residual heat removal mechanism, become unavailable. When this happens, the initiation of an F and B operation becomes necessary. As the number of the state increases, the necessity of an F and B operation increases. Especially, the operator should initiate an F and B operation when the RCS condition enters State 3 for Type 1 incidents or State 3-2 for Type 2 incidents. The results of this study may be useful in providing information regarding the necessity and effects of an F and B operation in a quantitative manner. In particular, in the case of a combined accident including a

Operation and safety decision-making support expert system in NPP

International Nuclear Information System (INIS)

Wei Yanhui; Su Desong; Chen Weihua; Zhang Jianbo

2014-01-01

The article first reviewed three operation support systems currently used in NPP: real-time information surveillance system, important equipment surveillance system and plant process control and monitoring system, then presents the structure and function of three expert support sub-systems (intelligent alarm monitoring system, computer-based operating procedure support system, safety information expert decision support system). Finally the article discussed the meaning of a kind of operation decision making support system. (authors)

A symptom based decision tree approach to boiling water reactor emergency operating procedures

International Nuclear Information System (INIS)

Knobel, R.C.

1984-01-01

This paper describes a Decision Tree approach to development of BWR Emergency Operating Procedures for use by operators during emergencies. This approach utilizes the symptom based Emergency Procedure Guidelines approved for implementation by the USNRC. Included in the paper is a discussion of the relative merits of the event based Emergency Operating Procedures currently in use at USBWR plants. The body of the paper is devoted to a discussion of the Decision Tree Approach to Emergency Operating Procedures soon to be implemented at two United States Boiling Water Reactor plants, why this approach solves many of the problems with procedures indentified in the post accident reviews of Three Mile Island procedures, and why only now is this approach both desirable and feasible. The paper discusses how nuclear plant simulators were involved in the development of the Emergency Operating Procedure decision trees, and in the verification and validation of these procedures. (orig./HP)

Making nuclear power plant operational decisions using probabilistic safety assessment information and personal computers. Working material

International Nuclear Information System (INIS)

1991-01-01

PRISIM described in this case study makes a PSA useful to decision makers like plant managers, operational personnel or safety assessors because it provides a rapid access to specific information and the ability to generate updated PSA results that reflect the plant status at a particular time. From the capabilities of PRISIM one can conclude that the ability of a user friendly update of the system model in the PC or changes in the data files at the computer is not realized to data. Also the calculation of averaged probabilities instead of time dependent instantaneous probabilities is a sort of a restriction and will be changed in the future. 5 refs, 34 figs, 3 tabs

AECL's support to operating plants world wide

International Nuclear Information System (INIS)

Azeez, S.; Kakaria, B.K.; Hinchley, E.M.

1998-01-01

Through their operating records, CANDU reactors have established themselves as a successful and cost-effective source of electricity in Canada and abroad. They have proven to be safe, reliable and economical. A variety of factors have contributed to the enviable CANDU record, such as a sound design based on proven principles supported by effective development programs, along with dedicated plant owners committed to excellence in safely maintaining and operating their plants. Atomic Energy of Canada Limited (AECL), the CANDU designer, has continuously maintained a close relationship with owners/operators of the plants in Canada, Argentina, Romania and South Korea. AECL and the plant operators have all benefited from this strengthening relationship by sharing experience and information. CANDU plant operators have been required to respond decisively to the economic realities of downward cost pressures and deregulation. Operating, Maintenance and Administration (OM and A) costs are being given a new focus as plant owners review each cost element to improve the economic returns from their investments. Amongst the three main OM and A constituents, plant maintenance costs are the most variable and have the largest influence on effective plant operations. The correlation between effective plant maintenance and high capacity factors shows clearly the importance of proactive maintenance planning to reduce the frequency and duration of forced plant outages and their negative impacts on plant economics. This paper describes the management processes and organizational structures m AECL that support plant operations and maintenance in operating CANDU plants with cost effective products and services. (author)

Quality assurance during operation of nuclear power plants

International Nuclear Information System (INIS)

1994-01-01

The general requirements applicable to the quality assurance of the Finnish nuclear power plants are presented in the Council of State Decision (395/91) and in the guide YVL 1.4. This guide specifies the quality assurance requirements to be applied during the operation of the nuclear power plants as well as of the other nuclear facilities. Quality assurance applies to all the activities and organizations with a bearing on the safe operation of the nuclear power plants. (5 refs.)

Simulation and experimental studies of operators' decision styles and crew composition while using an ecological and traditional user interface for the control room of a nuclear power plant

International Nuclear Information System (INIS)

Meshkati, N.; Buller, B.J.; Azadeh, M.A.

1995-01-01

The goal of this research is threefold: (1) use of the Skill-, Rule-, and Knowledge-based levels of cognitive control -- the SRK framework -- to develop an integrated information processing conceptual framework (for integration of workstation, job, and team design); (2) to evaluate the user interface component of this framework -- the Ecological display; and (3) to analyze the effect of operators' individual information processing behavior and decision styles on handling plant disturbances plus their performance on, and preference for, Traditional and Ecological user interfaces. A series of studies were conducted. In Part I, a computer simulation model and a mathematical model were developed. In Part II, an experiment was designed and conducted at the EBR-II plant of the Argonne National Laboratory-West in Idaho Falls, Idaho. It is concluded that: the integrated SRK-based information processing model for control room operations is superior to the conventional rule-based model; operators' individual decision styles and the combination of their styles play a significant role in effective handling of nuclear power plant disturbances; use of the Ecological interface results in significantly more accurate event diagnosis and recall of various plant parameters, faster response to plant transients, and higher ratings of subject preference; and operators' decision styles affect on both their performance and preference for the Ecological interface

Simulation and experimental studies of operators` decision styles and crew composition while using an ecological and traditional user interface for the control room of a nuclear power plant

Energy Technology Data Exchange (ETDEWEB)

Meshkati, N.; Buller, B.J.; Azadeh, M.A. [Univ. of Southern California, Los Angeles, CA (United States)

1995-04-01

The goal of this research is threefold: (1) use of the Skill-, Rule-, and Knowledge-based levels of cognitive control -- the SRK framework -- to develop an integrated information processing conceptual framework (for integration of workstation, job, and team design); (2) to evaluate the user interface component of this framework -- the Ecological display; and (3) to analyze the effect of operators` individual information processing behavior and decision styles on handling plant disturbances plus their performance on, and preference for, Traditional and Ecological user interfaces. A series of studies were conducted. In Part I, a computer simulation model and a mathematical model were developed. In Part II, an experiment was designed and conducted at the EBR-II plant of the Argonne National Laboratory-West in Idaho Falls, Idaho. It is concluded that: the integrated SRK-based information processing model for control room operations is superior to the conventional rule-based model; operators` individual decision styles and the combination of their styles play a significant role in effective handling of nuclear power plant disturbances; use of the Ecological interface results in significantly more accurate event diagnosis and recall of various plant parameters, faster response to plant transients, and higher ratings of subject preference; and operators` decision styles affect on both their performance and preference for the Ecological interface.

Operator decision support system for integrated wastewater management including wastewater treatment plants and receiving water bodies.

Science.gov (United States)

Kim, Minsoo; Kim, Yejin; Kim, Hyosoo; Piao, Wenhua; Kim, Changwon

2016-06-01

An operator decision support system (ODSS) is proposed to support operators of wastewater treatment plants (WWTPs) in making appropriate decisions. This system accounts for water quality (WQ) variations in WWTP influent and effluent and in the receiving water body (RWB). The proposed system is comprised of two diagnosis modules, three prediction modules, and a scenario-based supporting module (SSM). In the diagnosis modules, the WQs of the influent and effluent WWTP and of the RWB are assessed via multivariate analysis. Three prediction modules based on the k-nearest neighbors (k-NN) method, activated sludge model no. 2d (ASM2d) model, and QUAL2E model are used to forecast WQs for 3 days in advance. To compare various operating alternatives, SSM is applied to test various predetermined operating conditions in terms of overall oxygen transfer coefficient (Kla), waste sludge flow rate (Qw), return sludge flow rate (Qr), and internal recycle flow rate (Qir). In the case of unacceptable total phosphorus (TP), SSM provides appropriate information for the chemical treatment. The constructed ODSS was tested using data collected from Geumho River, which was the RWB, and S WWTP in Daegu City, South Korea. The results demonstrate the capability of the proposed ODSS to provide WWTP operators with more objective qualitative and quantitative assessments of WWTP and RWB WQs. Moreover, the current study shows that ODSS, using data collected from the study area, can be used to identify operational alternatives through SSM at an integrated urban wastewater management level.

Safety of Nuclear Power Plants: Commissioning and Operation

International Nuclear Information System (INIS)

2011-01-01

This publication is a revision of Safety Requirements No. NS-R-2, Safety of Nuclear Power Plants: Operation, and has been extended to cover the commissioning stage. It describes the requirements to be met to ensure the safe operation of nuclear power plants. Over recent years there have been developments in areas such as long term operation, plant ageing, periodic safety review, probabilistic safety analysis and risk informed decision making processes. It became necessary to revise the IAEA's safety requirements in these areas and to correct and/or improve the publication on the basis of feedback from its application by both the IAEA and its Member States. In addition, the requirements are governed by, and must apply, the safety objective and safety principles that are established in the Fundamental Safety Principles. Contents: 1. Introduction; 2. Safety objectives and principles; 3. The management and organizational structure of the operating organization; 4. Management of operational safety; 5. Operational safety programmes; 6. Plant commissioning; 7. Plant operations; 8. Maintenance, testing, surveillance and inspection; 9. Preparation for decommissioning.

Research of the Power Plant Operational Modes

Directory of Open Access Journals (Sweden)

Koismynina Nina M.

2017-01-01

Full Text Available In this article the algorithm of the power plant operational modes research is offered. According to this algorithm the program for the modes analysis and connection power transformers choice is developed. The program can be used as educational means for studying of the power plant electric part, at the same time basic data are provided. Also the program can be used for the analysis of the working power plants modes. Checks of the entered data completeness and a choice correctness of the operational modes are provided in the program; in all cases of a deviation from the correct decisions to the user the relevant information is given.

Support for decision making and problem solving in abnormal conditions in nuclear power plants

International Nuclear Information System (INIS)

Embrey, D.; Humphreys, P.

1985-01-01

Under abnormal plant condition effective decision support has to take into account the operator's or other decision maker's mental model of the plant, derived from operating experience. This will be different from the engineering model incorporated in Disturbance Analysis Systems. Recently developed approaches for gaining access to the structure of this mental model provided the basis for the development of an interactive computer system capable of representing and exploring expert knowledge concerning inferences about causal patterns, starting from the information available to the operator in the control room. This system has potential application as an interactive diagnostic aid in support of decision making and problem solving during abnormal conditions. (Auth.)

Data warehouse based decision support system in nuclear power plants

International Nuclear Information System (INIS)

Nadinic, B.

2004-01-01

Safety is an important element in business decision making processes in nuclear power plants. Information about component reliability, structures and systems, data recorded during the nuclear power plant's operation and outage periods, as well as experiences from other power plants are located in different database systems throughout the power plant. It would be possible to create a decision support system which would collect data, transform it into a standardized form and store it in a single location in a format more suitable for analyses and knowledge discovery. This single location where the data would be stored would be a data warehouse. Such data warehouse based decision support system could help make decision making processes more efficient by providing more information about business processes and predicting possible consequences of different decisions. Two main functionalities in this decision support system would be an OLAP (On Line Analytical Processing) and a data mining system. An OLAP system would enable the users to perform fast, simple and efficient multidimensional analysis of existing data and identify trends. Data mining techniques and algorithms would help discover new, previously unknown information from the data as well as hidden dependencies between various parameters. Data mining would also enable analysts to create relevant prediction models that could predict behaviour of different systems during operation and inspection results during outages. The basic characteristics and theoretical foundations of such decision support system are described and the reasons for choosing a data warehouse as the underlying structure are explained. The article analyzes obvious business benefits of such system as well as potential uses of OLAP and data mining technologies. Possible implementation methodologies and problems that may arise, especially in the field of data integration, are discussed and analyzed.(author)

Staffing decision processes and issues: Case studies of seven US Nuclear Power Plants

International Nuclear Information System (INIS)

Melber, B.; Roussel, A.; Baker, K.; Durbin, N.; Hunt, P.; Hauth, J.; Forslund, C.; Terrill, E.; Gore, B.

1994-03-01

The objective of this report is to identify how decisions are made regarding staffing levels and positions for a sample of U.S. nuclear power plants. In this report, a framework is provided for understanding the major forces driving staffing and the implications of staffing decisions for plant safety. The focus of this report is on driving forces that have led to changes in staffing levels and to the establishment of new positions between the mid-1980s and the early 1990s. Processes used at utilities and nuclear power plants to make and implement these staffing decisions are also discussed in the report. While general trends affecting the plant as a whole are presented, the major emphasis of this report is on staffing changes and practices in the operations department, including the operations shift crew. The findings in this report are based on interviews conducted at seven nuclear power plants and their parent utilities. A discussion of the key findings is followed by a summary of the implications of staffing issues for plant safety

Monitoring and operational support on nuclear power plants using an artificial intelligence system

International Nuclear Information System (INIS)

Bianchi, P.H.; Baptista Filho, B.D.

2009-01-01

The monitoring task in nuclear power plants is of crucial importance with respect to safety and efficient operation. The operators have a wide range of variables to observe and analyze; the quantity of variables and their behavior determine the time they have to take correct decisions. The complexity of such aspects in a nuclear power plant influences both, the plant operational efficiency and the general safety issues. This paper describes an experimental system developed by the authors which aims to assist the operators of nuclear power plants to take quick and safe decisions. The system maps the status of plant and helps the operators to make quick judgments by using artificial intelligence methods. The method makes use of a small set of monitored variables and presents a map of the plant status in a friendly manner. This system uses an architecture that has multiple self-organizing maps to perform these tasks. (author)

Monitoring and operational support on nuclear power plants using an artificial intelligence system

Energy Technology Data Exchange (ETDEWEB)

Bianchi, Paulo H.; Baptista Filho, Benedito D., E-mail: phbianchi@gmail.co, E-mail: bdbfilho@ipen.b [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

2009-07-01

The monitoring task in nuclear power plants is of crucial importance with respect to safety and efficient operation. The operators have a wide range of variables to observe and analyze; the quantity of variables and their behavior determine the time they have to take correct decisions. The complexity of such aspects in a nuclear power plant influences both, the plant operational efficiency and the general safety issues. This paper describes an experimental system developed by the authors which aims to assist the operators of nuclear power plants to take quick and safe decisions. The system maps the status of plant and helps the operators to make quick judgments by using artificial intelligence methods. The method makes use of a small set of monitored variables and presents a map of the plant status in a friendly manner. This system uses an architecture that has multiple self-organizing maps to perform these tasks. (author)

Method and apparatus for optimizing operation of a power generating plant using artificial intelligence techniques

Science.gov (United States)

Wroblewski, David [Mentor, OH; Katrompas, Alexander M [Concord, OH; Parikh, Neel J [Richmond Heights, OH

2009-09-01

A method and apparatus for optimizing the operation of a power generating plant using artificial intelligence techniques. One or more decisions D are determined for at least one consecutive time increment, where at least one of the decisions D is associated with a discrete variable for the operation of a power plant device in the power generating plant. In an illustrated embodiment, the power plant device is a soot cleaning device associated with a boiler.

Conduct of Operations at Nuclear Power Plants. Safety Guide (Spanish Edition)

International Nuclear Information System (INIS)

2012-01-01

This Safety Guide identifies the main responsibilities and practices of nuclear power plant (NPP) operations departments in relation to their responsibility for the safe functioning of the plant. The guide presents the factors to be considered in structuring the operations department of an NPP; setting high standards of performance; making safety related decisions in an effective manner; conducting control room and field activities in a thorough and professional manner; and maintaining an NPP within established operational limits and conditions. Contents: 1. Introduction; 2. Management and organization of plant operations; 3. Shift complement and functions; 4. Shift routines and operating practices; 5. Control of equipment and plant status; 6. Operations equipment and operator aids; 7. Work control and authorization.

Consideration of early closure or continued operation of a nuclear power plant

International Nuclear Information System (INIS)

2006-07-01

This publication provides information to management and executives of electrical utilities responsible for the operation of nuclear power plants who are tasked with decision making related to early closures or continued operation. This information is based on the experiences of a number of countries in addressing a spectrum of issues broader than only the economics of the operation of the plant itself. Any major decision involving changes in direction for a major investment such as a nuclear power plant has the potential to incur considerable additional costs for stakeholders. Major economic risks can be unexpectedly encountered when decisions based on a simplified economic understanding of energy options are successfully challenged on the grounds that choices and decisions have been made without accounting for some environmental, social or economic issues which are considered of prime significance to important stakeholders. Such risks include not only changes in project scope and delays in project implementation due to re-evaluations necessitated by such challenges, but risks related to the effectiveness, efficiency and safety of ongoing operations or shutdown maintenance of the nuclear power plant. Additional risks encountered at this stage are the adequacy of the decommissioning fund and the need to establish a process whereby the availability of adequate funds will be assured at the time of the final plant shutdown. This publication provides information on several of these additional issues important to key stakeholders, and on methods that allow for their assessment and consideration when developing recommendations related to early closures or continued operations of a NPP. This publication consists of two parts: Part I: Includes a discussion of the main issues for consideration, with emphasis on issues important to stakeholders in addition to plant owners. Part II: Provides an example of a basic analytical approach to the assessment of plant life cycle

Prototype equipment status monitor for plant operational configuration management

International Nuclear Information System (INIS)

DeVerno, M.; Trask, D.; Groom, S.

1998-01-01

CANDU plants, such as the Point Lepreau GS, have tens of thousands of operable devices. The status of each operable device must be immediately available to plan and execute future changes to the plant. Historically, changes to the plant's operational configuration have been controlled using manual and administrative methods where the status of each operable device is maintained on operational flowsheets located in the work control area of the main control room. The operational flowsheets are used to plan and develop Operating Orders (OOs) or Order-to-Operate (OTOs) and the control centre work processes are used to manage their execution. After performing each OO procedure, the operational flowsheets are updated to reflect the new plant configuration. This process can be very time consuming, and due to the manual processes, can lead to the potential for time lags and errors in the recording of the current plant configuration. Through a cooperative research and development program, Canadian CANDU utilities and Atomic Energy of Canada Limited, the design organization, have applied modern information technologies to develop a prototype Equipment Status Monitor (ESM) to address processes and information flow for efficient operational configuration management. The ESM integrates electronic operational flowsheets, equipment databases, engineering and work management systems, and computerized procedures to assess, plan, execute, track, and record changes to the plant's operational configuration. This directly leads to improved change control, more timely and accurate plant status information, fewer errors, and better decision making regarding future changes. These improvements to managing the plant's operational configuration are essential to increasing plant safety, achieving a high plant availability, and maintaining high capability and capacity factors. (author)

Plant specific risk informed decision making -a vision for Indian PHWR

International Nuclear Information System (INIS)

Guptan, Rajee; Mohan, Nalini; Ghadge, S.G.; Bajaj, S.S.

2006-01-01

The objective of Nuclear Power Plant (NPP) safety is to ensure and demonstrate that the risk from NPP to public and plant personnel is acceptably low. As a supplement to the deterministic approach, use of probabilistic techniques has been gaining grounds. Probabilistic Safety Assessment (PSA) is a popular international practice to calculate plant risk to the public, environment and plant personnel, in the event of an accident taking place in the plant. The risk posed by Nuclear Reactors to the Public at large is a very important issue in the public acceptance of a Nuclear Power Programme in any country. Risk Definition, generally accepted at present as the measure of possibility for an accidental event and severity of its effects to occur, simultaneously comprises both the probability (frequency) of potential damage occurrence and extent of this damage. NPCIL' s vision is to provide safe, reliable and cost effective energy to the nation by ensuring safe operation of the plants, limiting radiation exposure to plant personnel and public within prescribed limits. To achieve this vision our mission is to enhance the technical competency, resources and the awareness towards improved safety culture specific to Probabilistic Safety Assessment for applying PSA Studies to Risk Informed Decision making. This mission translates into the goal of completion of full scope PSA, with the co-operation and synergetic efforts of the Head quarters and Operating Station experts. NPCIL will then be self sufficient in applying Probabilistic Studies in Risk Informed Decision making to minimize risk and back fitting design changes to optimize the existing design and operating practices, thus providing for safe, reliable and cost effective energy to the nation. (author)

Genetic algorithms applied to the nuclear power plant operation

International Nuclear Information System (INIS)

Schirru, R.; Martinez, A.S.; Pereira, C.M.N.A.

2000-01-01

Nuclear power plant operation often involves very important human decisions, such as actions to be taken after a nuclear accident/transient, or finding the best core reload pattern, a complex combinatorial optimization problem which requires expert knowledge. Due to the complexity involved in the decisions to be taken, computerized systems have been intensely explored in order to aid the operator. Following hardware advances, soft computing has been improved and, nowadays, intelligent technologies, such as genetic algorithms, neural networks and fuzzy systems, are being used to support operator decisions. In this chapter two main problems are explored: transient diagnosis and nuclear core refueling. Here, solutions to such kind of problems, based on genetic algorithms, are described. A genetic algorithm was designed to optimize the nuclear fuel reload of Angra-1 nuclear power plant. Results compared to those obtained by an expert reveal a gain in the burn-up cycle. Two other genetic algorithm approaches were used to optimize real time diagnosis systems. The first one learns partitions in the time series that represents the transients, generating a set of classification centroids. The other one involves the optimization of an adaptive vector quantization neural network. Results are shown and commented. (orig.)

Method for plant operation guidance by knowledge engineering technique

International Nuclear Information System (INIS)

Kiguchi, Takashi; Yoshida, Kenichi; Motoda, Hiroshi; Kobayashi, Setsuo

1983-01-01

A method for plant operation guidance has been developed by using the Knowledge Engineering technique. The method is characterized by its capability of handling plant dynamics. The knowledge-base includes plant simulation programs as tools to evaluate dynamic behaviors as well as production rules of ''if..., then...'' type. The inference engine is thus capable of predicting plant dynamics and making decisions in accordance with time progress. The performance of the guidance method was evaluated by simulation tests assuming various abnormal situations of a BWR power plant. It was shown that the method can detect each of the abnormal events along the course of their occurrence, and provide the guidance for corrective actions. The operation guidance method proposed in this paper is general and is applicable not only to nuclear power plants but also to other plants such as chemical production plants and fossile power plants. (author)

Safety of Nuclear Power Plants: Commissioning and Operation (Spanish Edition)

International Nuclear Information System (INIS)

2012-01-01

This publication is a revision of Safety Requirements No. NS-R-2, Safety of Nuclear Power Plants: Operation, and has been extended to cover the commissioning stage. It describes the requirements to be met to ensure the safe operation of nuclear power plants. Over recent years there have been developments in areas such as long term operation, plant ageing, periodic safety review, probabilistic safety analysis and risk informed decision making processes. It became necessary to revise the IAEA's safety requirements in these areas and to correct and/or improve the publication on the basis of feedback from its application by both the IAEA and its Member States. In addition, the requirements are governed by, and must apply, the safety objective and safety principles that are established in the Fundamental Safety Principles. Contents: 1. Introduction; 2. Safety objectives and principles; 3. The management and organizational structure of the operating organization; 4. Management of operational safety; 5. Operational safety programmes; 6. Plant commissioning; 7. Plant operations; 8. Maintenance, testing, surveillance and inspection; 9. Preparation for decommissioning.

Safety of Nuclear Power Plants: Commissioning and Operation (French Edition)

International Nuclear Information System (INIS)

2012-01-01

This publication is a revision of Safety Requirements No. NS-R-2, Safety of Nuclear Power Plants: Operation, and has been extended to cover the commissioning stage. It describes the requirements to be met to ensure the safe operation of nuclear power plants. Over recent years there have been developments in areas such as long term operation, plant ageing, periodic safety review, probabilistic safety analysis and risk informed decision making processes. It became necessary to revise the IAEA's safety requirements in these areas and to correct and/or improve the publication on the basis of feedback from its application by both the IAEA and its Member States. In addition, the requirements are governed by, and must apply, the safety objective and safety principles that are established in the Fundamental Safety Principles. Contents: 1. Introduction; 2. Safety objectives and principles; 3. The management and organizational structure of the operating organization; 4. Management of operational safety; 5. Operational safety programmes; 6. Plant commissioning; 7. Plant operations; 8. Maintenance, testing, surveillance and inspection; 9. Preparation for decommissioning.

Safety of Nuclear Power Plants: Commissioning and Operation. Arabic Edition

International Nuclear Information System (INIS)

2011-01-01

This publication is a revision of Safety Requirements No. NS-R-2, Safety of Nuclear Power Plants: Operation, and has been extended to cover the commissioning stage. It describes the requirements to be met to ensure the safe operation of nuclear power plants. Over recent years there have been developments in areas such as long term operation, plant ageing, periodic safety review, probabilistic safety analysis and risk informed decision making processes. It became necessary to revise the IAEA's safety requirements in these areas and to correct and/or improve the publication on the basis of feedback from its application by both the IAEA and its Member States. In addition, the requirements are governed by, and must apply, the safety objective and safety principles that are established in the Fundamental Safety Principles. Contents: 1. Introduction; 2. Safety objectives and principles; 3. The management and organizational structure of the operating organization; 4. Management of operational safety; 5. Operational safety programmes; 6. Plant commissioning; 7. Plant operations; 8. Maintenance, testing, surveillance and inspection; 9. Preparation for decommissioning.

Application study of non-linear reasoning for nuclear plant operation

International Nuclear Information System (INIS)

Yoshikawa, Shinji; Yonekawa, Tsuyoshi; Suda, Kazunori; Hasegawa, Makoto

1999-03-01

Achievement of improved operation safety of complex nuclear power plants by decision-making functions based on information processing technologies requires real time concluding to be in-time for plant state evolutions, transparency for human operators to understand the derived conclusion, and robustness against local defects inevitably hidden in huge amount of the referred information. These requirements can not be met by the simple rule-based reasoning. The study introduced in this report put a focus on the robustness of the three requirements. This study derives the required feature of robust decision making, after thinking of possible contribution of fast emerging measurement technologies. Finally, two concrete algorithm based on mutual evaluation of relatively simple diagnostic modules are implemented on computer systems and evaluated in views of applicability. (author)

Assuring human operator alertness at night in power plants

International Nuclear Information System (INIS)

Moore-Ede, M.C.

1988-01-01

The human body is not designed for peak alertness and performance at night, nor is it well-equipped to cope with the frequent day-night inversions required by rotating shift work schedules. As a result, the human operator can become the weak link in a complex technological operation such as a nuclear power plant. The high degree of dependence on human operator vigilance, decision-making ability and performance that is required in nuclear power plant operations can conflict with the human sleepiness and error-proneness which naturally occur during the night shift or after extended periods without adequate sleep. An opportunity to address these problems has come from a series of major research advances in basic circadian physiology

Pre-IPO Operational and Financial Decisions

OpenAIRE

Volodymyr Babich; Matthew J. Sobel

2004-01-01

Many owners of growing privately held firms make operational and financial decisions in an effort to maximize the expected present value of the proceeds from an initial public offering (IPO). We ask: ÜWhat is the right time to make an IPO?Ý and ÜHow should operational and financial decisions be coordinated to increase the likelihood of a successful IPO?Ý Financial and operational decisions in this problem are linked because adequate financial capital is crucial for operational decisions to be...

Development of an integrated decision support system to aid cognitive activities of operators

International Nuclear Information System (INIS)

Lee, Seung Jun; Seong, Poong Hyun

2007-01-01

As digital and computer technologies have grown, Human-Machine Interfaces (HMIs) have evolved. In safety-critical systems, especially in Nuclear Power Plants (NPPs), HMIs are important for reducing operational costs, the number of necessary operators, and the probability of accident occurrence. Efforts have been made to improve Main Control Room (MCR) interface design and to develop automated or decision support systems to ensure convenient operation and maintenance. In this paper, an integrated decision support system to aid operator cognitive processes is proposed for advanced MCRs of future NPPs. This work suggests the design concept of a decision support system which accounts for an operator's cognitive processes. The proposed system supports not only a particular task, but also the entire operation process based on a human cognitive process model. In this paper, the operator's operation processes are analyzed according to a human cognitive process model and appropriate support systems that support each cognitive process activity are suggested

Intelligent decision aids for abnormal events in nuclear power plants

International Nuclear Information System (INIS)

Kafka, P.; Polke, H.

1988-01-01

German nuclear power plants are characterized by a high degree of automation, not only for normal operation but also for abnormal events. Therefore the role of the operating personnel is mainly a supervisory function. Nevertheless, for a spectrum of unexpected events the operating personnel have to react with manual recovery actions. In order to minimize human error in such recovery actions, different kinds of intelligent decision aid support the operators today. In this paper such aids are discussed and one of them is described in more detail. (author)

Plant life extensions for German nuclear power plants? Controversial discussion profit taking of nuclear power plant operators

International Nuclear Information System (INIS)

Matthes, Felix C.

2009-10-01

The discussion on the plant life extensions for German nuclear power plants beyond the residual quantity of electricity particularly focus on three aspects: Effects for the emission of carbon dioxide as a greenhouse gas; Development of the electricity price for which a reduction or attenuation is postulated due to a plant life extension; Skimming of additional profits at operating companies and their use in the safeguarding of the future (development of renewable energies, support of energy efficiency, promotion of the research, consolidation of the public budget, and so on). Under this aspect, the author of the contribution under consideration reports on the profit taking of nuclear power plant operators. The presented analysis considers three aspects: (a) Specification of the quantity structures for the investigated model of plant life extension; (b) The decisive parameter is the revenue situation and thus the price development for electricity at wholesale markets; (c) Determination and evaluation of the course in time of the profit taking.

GLObal RIsk MANagement system for plant operations GLORIMAN

International Nuclear Information System (INIS)

Silverman, Eugene B.

2004-01-01

Considerable effort has been expended by nuclear power plants in the preparation of their Independent Plant Evaluation (IPE) programs. The result of these projects is the generation of very useful information concerning plant operations, states, availability and risk. The potential application of this information is often unrealized due to the unwieldy form of the data as reported in the IPE. Plant personnel would benefit greatly from quick access to risk information as a means of supporting day-to-day decisions, but the information exists only in a difficult to understand and inaccessible form. There is a need to translate the costs invested in Probabilistic Risk Assessment (PRA) projects into a useable tool for plant personnel. This paper describes a software tool developed by ARD Corporation to be used by plants to assist in determining the operational risks and benefits associated with modifying the plant state during normal and off-normal operations for performing maintenance. This tool integrates a relational database with an easy-to-use graphical user interface and several unique software features. The result is a responsive, easy-to-understand tool that integrates an organization's PRA/IPE into the operational and maintenance needs of the station. The Global Risk Management System is designed to allow the user to evaluate the risk associated with current and proposed plant states. The impact of changes in plant configuration, operational modes and equipment availability are assessed from a risk management perspective, but displayed in an easy-to-understand form for personnel not familiar with risk methodology. Additionally, pipe and instrumentation drawings can be retrieved by the user and displayed as a reference tool. (author)

Expert system of real time for support of operators of atomic power plants

International Nuclear Information System (INIS)

Bashlykov, A.A.; Davidenko, N.N.; Dumshev, V.G.; Kislov, G.I.; Pavlova, E.V.; Prozorovskij, E.D.; Bashlykov, A.A.

1994-01-01

The problems of construction and introdution of an intellectual system for information support of operators at nuclear power plants are discussed. This system is used for operator assisstance during real time decision making for NPP operational regime control

Tactical and strategic decision-making aids for nuclear power plant emergency response

International Nuclear Information System (INIS)

Cain, D.G.

1987-01-01

This paper examines the prospective role of computer-based decision aids for nuclear power plant emergency response. The role of these systems is subordinate to human activities, but in a complementary manner these systems process decision logic more accurately and foster a more thorough understanding of emergency situations than might other wise be possible. Within this context two decision support systems being developed are discussed. Both of these systems utilize technology derived from artificial intelligence, focussing on two different facets of emergency response. An automated emergency operating procedures (EOP) tracking expert system is described as a tactical aid for control room operator response. A reactor emergency action level monitor (REALM) expert system is proposed as a strategic decision aid for site emergency response. The discrimination between tactical and strategic decision-making is an intrinsic part of this examination

A predictive model of nuclear power plant crew decision-making and performance in a dynamic simulation environment

Science.gov (United States)

Coyne, Kevin Anthony

The safe operation of complex systems such as nuclear power plants requires close coordination between the human operators and plant systems. In order to maintain an adequate level of safety following an accident or other off-normal event, the operators often are called upon to perform complex tasks during dynamic situations with incomplete information. The safety of such complex systems can be greatly improved if the conditions that could lead operators to make poor decisions and commit erroneous actions during these situations can be predicted and mitigated. The primary goal of this research project was the development and validation of a cognitive model capable of simulating nuclear plant operator decision-making during accident conditions. Dynamic probabilistic risk assessment methods can improve the prediction of human error events by providing rich contextual information and an explicit consideration of feedback arising from man-machine interactions. The Accident Dynamics Simulator paired with the Information, Decision, and Action in a Crew context cognitive model (ADS-IDAC) shows promise for predicting situational contexts that might lead to human error events, particularly knowledge driven errors of commission. ADS-IDAC generates a discrete dynamic event tree (DDET) by applying simple branching rules that reflect variations in crew responses to plant events and system status changes. Branches can be generated to simulate slow or fast procedure execution speed, skipping of procedure steps, reliance on memorized information, activation of mental beliefs, variations in control inputs, and equipment failures. Complex operator mental models of plant behavior that guide crew actions can be represented within the ADS-IDAC mental belief framework and used to identify situational contexts that may lead to human error events. This research increased the capabilities of ADS-IDAC in several key areas. The ADS-IDAC computer code was improved to support additional

Expert systems to assist plant operation

International Nuclear Information System (INIS)

Matsumoto, Yoshihiro; Mori, Nobuyuki; Wada, Norio

1985-01-01

Large-scale real-time process control systems, such as those for electric power dispatching, large thermal and nuclear power stations, steel mill plants and manufacturing automation systems, need expert systems to assist operator's decision. The expert systems newly developed to fulfill the requirement are founded on OKBS (object oriented knowledge based system). OKBS provides various object types: fuzzy logic type, production rule type, frame type, state transition type, abstract data type and input/output transformation type. (author)

The operational benefits of integrated PC control of gamma irradiation plants

International Nuclear Information System (INIS)

Comben, M.; Stephens, P.

1998-01-01

Compared with the traditional PLC control systems used on many gamma irradiation plants, the semi-intelligent decision making capabilities of a fully integrated PC control system can bring many benefits to the plant operator. The authors will describe how plant operation is fully automatic with the PC control providing all the input-output data required to run the plant efficiently and safely. Detailed product tracking, with live on-screen data, can be incorporated to give both plant operator and product manufacturer complete confidence in the irradiation process. Advanced features such as on-line diagnostics and mechanical part failure prediction are also described. Also available is automated dosimetry, reducing the opportunity for human error, whilst at the same time saving on staff costs and providing highly professional dose validation reports and comprehensive routine dosimetry documentation. The benefits of PURIDEC's PC control system are not only available with its new plants. The system can be supplied as an upgrade to plants of all ages and design giving the current operator all the benefits described in the paper

Conduct of inspections for plant modifications, event investigations and operability decisions. Proceedings of an International Workshop

International Nuclear Information System (INIS)

1995-01-01

Preliminary planning started following the approval given by the CNRA. Formal planning for the Workshop was started at the Fifth Meeting of the WGIP in April 1993, in Lyon. Planning included taking into consideration comments made and lessons learned at the first Workshop. The first organising committee meeting for the Workshop was held in London preceding the Sixth WGIP meeting in October 1993. It was decided to remain with the same format: discussion groups with facilitators. It was also decided to have a three day programme with three Discussion Group sessions. The Announcement and Call for Participation was issued in December 1993. As part of the Announcement and Call for Participation, registrants were requested to transmit questions or issues of particular interest within the selected topics, they wanted to be addressed at the Workshop. A compilation of the these is included as Appendix H. Additionally, participants were requested to provide a short paper of one or two pages, describing the practices within their own countries related to the topics, for utilisation during the discussion sessions. These papers are attached as Appendix I. A training session was held for all facilitators on the afternoon of 22 May, to introduce methods in leading small group discussions and to complete final preparations. The Workshop programme (Appendix B) consisted of an opening plenary session, 3 discussion group sessions and a closing plenary session to review conclusions and an open question period. Following completion of the Workshop, facilitators met to evaluate and formulate final reports on the various topics. The main objectives of the Workshop were the following: To meet with inspectors from other organisations, To exchange information regarding regulatory inspections practices, To discuss the major topics: plant modifications, event investigation, and operability decisions, To discuss current issues, To develop conclusions on the topics discussed. Six discussion

Conduct of inspections for plant modifications, event investigations and operability decisions. Proceedings of an International Workshop

Energy Technology Data Exchange (ETDEWEB)

NONE

1995-07-01

Preliminary planning started following the approval given by the CNRA. Formal planning for the Workshop was started at the Fifth Meeting of the WGIP in April 1993, in Lyon. Planning included taking into consideration comments made and lessons learned at the first Workshop. The first organising committee meeting for the Workshop was held in London preceding the Sixth WGIP meeting in October 1993. It was decided to remain with the same format: discussion groups with facilitators. It was also decided to have a three day programme with three Discussion Group sessions. The Announcement and Call for Participation was issued in December 1993. As part of the Announcement and Call for Participation, registrants were requested to transmit questions or issues of particular interest within the selected topics, they wanted to be addressed at the Workshop. A compilation of the these is included as Appendix H. Additionally, participants were requested to provide a short paper of one or two pages, describing the practices within their own countries related to the topics, for utilisation during the discussion sessions. These papers are attached as Appendix I. A training session was held for all facilitators on the afternoon of 22 May, to introduce methods in leading small group discussions and to complete final preparations. The Workshop programme (Appendix B) consisted of an opening plenary session, 3 discussion group sessions and a closing plenary session to review conclusions and an open question period. Following completion of the Workshop, facilitators met to evaluate and formulate final reports on the various topics. The main objectives of the Workshop were the following: To meet with inspectors from other organisations, To exchange information regarding regulatory inspections practices, To discuss the major topics: plant modifications, event investigation, and operability decisions, To discuss current issues, To develop conclusions on the topics discussed. Six discussion

A decision support system for maintenance management of a boiling-water reactor power plant

International Nuclear Information System (INIS)

Shen, J.H.; Ray, A.; Levin, S.

1996-01-01

This article reports the concept and development of a prototype expert system to serve as a decision support tool for maintenance of boiling-water reactor (BWR) nuclear power plants. The code of the expert system makes use of the database derived from the two BWR units operated by the Pennsylvania Power and Light Company in Berwick, Pennsylvania. The operations and maintenance information from a large number of plant equipment and sub-systems that must be available for emergency conditions and in the event of an accident is stored in the database of the expert system. The ultimate goal of this decision support tool is to identify the relevant Technical Specifications and management rules for shutting down any one of the plant sub-systems or removing a component from service to support maintenance. 6 refs., 7 figs

Plant operator performance evaluation based on cognitive process analysis experiment

International Nuclear Information System (INIS)

Ujita, H.; Fukuda, M.

1990-01-01

This paper reports on an experiment to clarify plant operators' cognitive processes that has been performed, to improve the man-machine interface which supports their diagnoses and decisions. The cognitive processes under abnormal conditions were evaluated by protocol analyses interviews, etc. in the experiment using a plant training simulator. A cognitive process model is represented by a stochastic network, based on Rasmussen's decision making model. Each node of the network corresponds to an element of the cognitive process, such as observation, interpretation, execution, etc. Some observations were obtained as follows, by comparison of Monte Carlo simulation results with the experiment results: A process to reconfirm the plant parameters after execution of a task and feedback paths from this process to the observation and the task definition of next task were observed. The feedback probability average and standard deviation should be determined for each incident type to explain correctly the individual differences in the cognitive processes. The tendency for the operator's cognitive level to change from skill-based to knowledge-based via rule-based behavior was observed during the feedback process

Theoretical and Experimental Impact Analysis of Decision Support Systems for Advanced MCR Operators

International Nuclear Information System (INIS)

Lee, Seung Jun; Seong, Poong Hyun

2008-01-01

Human error is recognized as one of the main causes of nuclear power plant (NPP) accidents, and there have been efforts to reduce and prevent human errors by developing various operator support systems. Before adapting these support systems to actual NPPs, it is necessary to validate their reliability and to evaluate their effect on operator performance. Particularly for safety-critical systems such as NPPs, the validation and evaluation of support systems is as important as the design of good systems. Such evaluations may be carried out through a theoretical modelling or experimentation. The objective of this study is to investigate the effects of decision support systems on operator performance by both theoretical and experimental methods. The target system is an integrated decision support system including four decision support sub-systems. In the results of both the theoretical and experimental evaluations, the decision support systems revealed positive effects, and several trends were observed. (authors)

Theoretical and Experimental Impact Analysis of Decision Support Systems for Advanced MCR Operators

Energy Technology Data Exchange (ETDEWEB)

Lee, Seung Jun [Korea Atomic Energy Research Institute, 1045 Daedeok-daero, Yuseong-gu, Daejeon, 305-353 (Korea, Republic of); Seong, Poong Hyun [Korea Advanced Institute of Science and Technology, Guseong-dong, Yuseong-gu, Daejeon, 305-703 (Korea, Republic of)

2008-07-01

Human error is recognized as one of the main causes of nuclear power plant (NPP) accidents, and there have been efforts to reduce and prevent human errors by developing various operator support systems. Before adapting these support systems to actual NPPs, it is necessary to validate their reliability and to evaluate their effect on operator performance. Particularly for safety-critical systems such as NPPs, the validation and evaluation of support systems is as important as the design of good systems. Such evaluations may be carried out through a theoretical modelling or experimentation. The objective of this study is to investigate the effects of decision support systems on operator performance by both theoretical and experimental methods. The target system is an integrated decision support system including four decision support sub-systems. In the results of both the theoretical and experimental evaluations, the decision support systems revealed positive effects, and several trends were observed. (authors)

Long Term Operation R and D to Investigate the Technical Basis for Life Extension and License Renewal Decisions

International Nuclear Information System (INIS)

Gaertner, John

2012-01-01

Establishing an improved technical basis for long term operation of existing plants is a nuclear industry priority. The Electric Power Research Institute (EPRI) has responded with a comprehensive Long Term Operation (LTO) Program addressing this need for existing nuclear power plants world-wide. The program supports both the business decisions necessary to achieve high performance operation and the licensing requirements for operation beyond 60 years. The program selects its R and D priorities in a structured and objective way with much industry input to provide useful results for decisions in the 2014 to 2019 time frame. The program is highly collaborative with U.S. Department of Energy (DOE) and with EPRI-member utilities. The R and D portfolio includes materials aging (metals, concrete, and cables), modernization of information and control technology, enhanced safety analysis, advanced fuel design, demonstration plant activities, life cycle management, and identification of aging management program need for subsequent license renewal. The program has focussed stakeholders world-wide on the technical issues of long term operation, and it is on-track to provide practical results for life extension and license renewal decisions. (author)

Post-event human decision errors: operator action tree/time reliability correlation

International Nuclear Information System (INIS)

Hall, R.E.; Fragola, J.; Wreathall, J.

1982-11-01

This report documents an interim framework for the quantification of the probability of errors of decision on the part of nuclear power plant operators after the initiation of an accident. The framework can easily be incorporated into an event tree/fault tree analysis. The method presented consists of a structure called the operator action tree and a time reliability correlation which assumes the time available for making a decision to be the dominating factor in situations requiring cognitive human response. This limited approach decreases the magnitude and complexity of the decision modeling task. Specifically, in the past, some human performance models have attempted prediction by trying to emulate sequences of human actions, or by identifying and modeling the information processing approach applicable to the task. The model developed here is directed at describing the statistical performance of a representative group of hypothetical individuals responding to generalized situations

Post-event human decision errors: operator action tree/time reliability correlation

Energy Technology Data Exchange (ETDEWEB)

Hall, R E; Fragola, J; Wreathall, J

1982-11-01

This report documents an interim framework for the quantification of the probability of errors of decision on the part of nuclear power plant operators after the initiation of an accident. The framework can easily be incorporated into an event tree/fault tree analysis. The method presented consists of a structure called the operator action tree and a time reliability correlation which assumes the time available for making a decision to be the dominating factor in situations requiring cognitive human response. This limited approach decreases the magnitude and complexity of the decision modeling task. Specifically, in the past, some human performance models have attempted prediction by trying to emulate sequences of human actions, or by identifying and modeling the information processing approach applicable to the task. The model developed here is directed at describing the statistical performance of a representative group of hypothetical individuals responding to generalized situations.

Role of cognitive models of operators in the design, operation and licensing of nuclear power plants

International Nuclear Information System (INIS)

Rasmussen, J.

1982-01-01

Cognitive models of the behavior of nuclear power plant operators - that is, models developed in terms of human properties rather than external task characteristics - are assuming increasingly important roles in plant design, operation and licensing. This is partly due to an increased concern for human decision making during unfamiliar plant conditions, and partly due to problems that arise when modern information technology is used to support operators in complex situations. Some of the problems identified during work on interface design and risk analysis are described. First, the question of categories of models is raised. Next, the use of cognitive models for system design is discussed. The use of the available cognitive models for more effective operator training is also advocated. The need for using cognitive models in risk analysis is also emphasized. Finally, the sources of human performance data, that is, event reports, incident analysis, experiments, and training simulators are mentioned, and the need for a consistent framework for data analysis based on cognitive models is discussed

A judgment and decision-making model for plant behavior.

Science.gov (United States)

Karban, Richard; Orrock, John L

2018-06-12

Recently plant biologists have documented that plants, like animals, engage in many activities that can be considered as behaviors, although plant biologists currently lack a conceptual framework to understand these processes. Borrowing the well-established framework developed by psychologists, we propose that plant behaviors can be constructively modeled by identifying four distinct components: 1) a cue or stimulus that provides information, 2) a judgment whereby the plant perceives and processes this informative cue, 3) a decision whereby the plant chooses among several options based on their relative costs and benefits, and 4) action. Judgment for plants can be determined empirically by monitoring signaling associated with electrical, calcium, or hormonal fluxes. Decision-making can be evaluated empirically by monitoring gene expression or differential allocation of resources. We provide examples of the utility of this judgment and decision-making framework by considering cases in which plants either successfully or unsuccessfully induced resistance against attacking herbivores. Separating judgment from decision-making suggests new analytical paradigms (i.e., Bayesian methods for judgment and economic utility models for decision-making). Following this framework, we propose an experimental approach to plant behavior that explicitly manipulates the stimuli provided to plants, uses plants that vary in sensory abilities, and examines how environmental context affects plant responses. The concepts and approaches that follow from the judgment and decision-making framework can shape how we study and understand plant-herbivore interactions, biological invasions, plant responses to climate change, and the susceptibility of plants to evolutionary traps. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

Contribution of quality assurance to effective nuclear power plant operation

International Nuclear Information System (INIS)

Raisic, N.

1984-01-01

The regulatory requirements related to quality assurance (QA) serve as an effective mechanism in establishing and implementing the QA programme during the design, construction and operation of nuclear power plants. However, these requirements only relate to the equipment and activities concerning the safety of nuclear power plants; the decision as to their implementation on other non-safety-related equipment is left to the plant management. As a result, operation statistics show that the safety-related systems are performing satisfactorily and that they are not of serious concern to plant unavailability. On the other hand, non-safety-related equipment which is still vital to plant performances is more frequently responsible for plant outages and losses in electricity production. QA programmes implemented on such equipment are in principle less strict, unsystematic and, in a number of cases, non-existent. An attempt has been made to analyse the existing operating experience data in order to identify the correlation of outage statistics with QA programmes required by existing standards and their implementation practices, both in respect of programme coverage and intensity. Unfortunately, existing operating experience data cannot directly correlate plant performance with the QA programmes implemented in order to demonstrate the effectiveness of QA techniques to plant safety, reliability of plant equipment and plant availability. For these reasons an analysis is made of outage statistics to identify the modes and causes of outages and to relate them to existing QA requirements and practices. Some conclusions are deduced that relate to a possible improvement of plant performance by consequent implementation of QA requirements to the equipment and activities responsible for both plant safety and efficient electricity production, and by adequate grading of QA activities to obtain a cost-effective QA programme in plant operation. (author)

Using management of aging in German nuclear power plants - aspects of KTA 1403 pertaining to residual power operation, post-shutdown operation and residual operation

International Nuclear Information System (INIS)

Barreiro, Pablo; Bever, Thomas; Brast, Gerhard; Elsche, Bjoern; Reese, Sven H.; Grossmann, Patrick; Widera, Martin; Huettner, Frank; Linnemann, Thomas; Smit, Swen-Olaf; Zander, Ralf-Michael

2013-01-01

Management of aging in nuclear power plants originated in the United States of America and became a topic of debate in Germany from the late 1990s onward. On the basis of the existing plant-specific measures practiced comprehensively, KTA 1403, ''Management of Aging in Nuclear Power Plants'', was drafted and finalized in 2010. This publication first presents the context of AM with regard to German nuclear power plants, including references to national and international historical developments. Against this backdrop, the difference between management of aging and lifetime management is discussed next. This is followed by a description of the status of the AM process in nuclear power plants currently in operation, especially organizational plant-specific implementation. As a consequence of the decision by the German federal government to discontinue the peaceful use of nuclear power in Germany and the associated 13th amendment to the Atomic Energy Act of July 31, 2011, a considerable part of the German nuclear power plant park already lost its right of power operation. In this situation, aspects of AM are discussed for plants in the no-power, post-operation and residual operation phases. Finally, experience accumulated in plant-specific execution of the AM process on the basis of KTA 1403 is considered and summarized.

Safety of Nuclear Power Plants: Commissioning and Operation. Specific Safety Requirements

International Nuclear Information System (INIS)

2016-01-01

This publication describes the requirements to be met to ensure the safe operation of nuclear power plants. It takes into account developments in areas such as long term operation of nuclear power plants, plant ageing, periodic safety review, probabilistic safety analysis and risk informed decision making processes. In addition, the requirements are governed by, and must apply, the safety objective and safety principles that are established in the IAEA Safety Standards Series No. SF-1, Fundamental Safety Principles. A review of Safety Requirements publications was commenced in 2011 following the accident in the Fukushima Daiichi nuclear power plant in Japan. The review revealed no significant areas of weakness and resulted in just a small set of amendments to strengthen the requirements and facilitate their implementation, which are contained in the present publication

Improving nuclear power plant safety through operator aids

International Nuclear Information System (INIS)

1987-12-01

In October 1986, the IAEA convened a one-week Technical Committee Meeting on Improving Nuclear Power Plant Safety Through Operator Aids. The term ''operator aid'' or more formally ''operator support system'' refers to a class of devices designed to be added to a nuclear power plant control station to assist an operator in performing his job and thereby decrease the probability of operator error. The addition of a carefully planned and designed operator aid should result in an increase in nuclear power plant safety and reliability. Operator aids encompass a wide range of devices from the very simple, such as color coding a display to distinguish it out of a group of similar displays, to the very complex, such as a computer-generated video display which concentrates a number of scattered indicator readings located around a control room into a concise display in front of the operator. This report provides guidelines and information to help make a decision as to whether an operator aid is needed, what kinds of operator aids are available and whether it should be purchased or developed by the utility. In addition, a discussion is presented on advanced operator aids to provide information on what may become available in the future. The broad scope of these guidelines makes it most suitable for use by a multi-disciplinary team. The document consists of two parts. The recommendations and results of the meeting discussions are given in the first part. The second part is the annex where the papers presented at the Technical Committee Meeting are printed. A separate abstract was prepared for each of the 10 papers. Refs, figs and tabs

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

International Nuclear Information System (INIS)

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

1999-01-01

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

A decision-making framework for protecting process plants from flooding based on fault tree analysis

International Nuclear Information System (INIS)

Hauptmanns, Ulrich

2010-01-01

The protection of process plants from external events is mandatory in the Seveso Directive. Among these events figures the possibility of inundation of a plant, which may cause a hazard by disabling technical components and obviating operator interventions. A methodological framework for dealing with hazards from potential flooding events is presented. It combines an extension of the fault tree method with generic properties of flooding events in rivers and of dikes, which should be adapted to site-specific characteristics in a concrete case. Thus, a rational basis for deciding whether upgrading is required or not and which of the components should be upgraded is provided. Both the deterministic and the probabilistic approaches are compared. Preference is given to the probabilistic one. The conclusions drawn naturally depend on the scope and detail of the model calculations and the decision criterion adopted. The latter has to be supplied from outside the analysis, e.g. by the analyst himself, the plant operator or the competent authority. It turns out that decision-making is only viable if the boundary conditions for both the procedure of analysis and the decision criterion are clear.

Managing the early termination of operation of nuclear power plants

International Nuclear Information System (INIS)

2003-01-01

The International Atomic Energy Agency (IAEA) has the statutory mandate to seek to accelerate and enlarge the contribution of atomic energy to peace, health and prosperity throughout the world. However, it has become more and more apparent that many States are facing the decision of closing nuclear power plants (NPPs) before expiration of their operating licences. Some NPPs have already closed and the owners are evaluating the effects on their staffs, the local economies and safety at the sites. It is evident that safety aspects and management strategies are important factors to be reviewed and monitored throughout the process of early termination and closure.The owners and employees of the NPPs are realizing that they are entering into very difficult phases of the plant life cycle with significant safety concerns. Although a great deal of work has been done to review and process information on technical aspects of early termination prior to decommissioning, far less attention has been given to the management and organizational issues involved in maintaining the required safety level in such nuclear installations. It is important that when decisions are made to terminate operation early, the same safety measures are applied to management concerns for strategic planning as are applied to technical reviews. These management and organizational issues are fundamental to any future decommissioning process. Managers at sites that decided to close early may be working to cope with management of change issues arising during the transition from operation to decommissioning as they monitor resource and competence needs, as well as staff morale and technical issues. If these issues are not treated satisfactorily they can have significant safety consequences. The organization often must address all these challenges with little guidance or experience and with reduced resources. This Safety Report has been developed with the support of experts from regulatory, operating and

Developing a Hierarchical Decision Model to Evaluate Nuclear Power Plant Alternative Siting Technologies

Science.gov (United States)

Lingga, Marwan Mossa

A strong trend of returning to nuclear power is evident in different places in the world. Forty-five countries are planning to add nuclear power to their grids and more than 66 nuclear power plants are under construction. Nuclear power plants that generate electricity and steam need to improve safety to become more acceptable to governments and the public. One novel practical solution to increase nuclear power plants' safety factor is to build them away from urban areas, such as offshore or underground. To date, Land-Based siting is the dominant option for siting all commercial operational nuclear power plants. However, the literature reveals several options for building nuclear power plants in safer sitings than Land-Based sitings. The alternatives are several and each has advantages and disadvantages, and it is difficult to distinguish among them and choose the best for a specific project. In this research, we recall the old idea of using the alternatives of offshore and underground sitings for new nuclear power plants and propose a tool to help in choosing the best siting technology. This research involved the development of a decision model for evaluating several potential nuclear power plant siting technologies, both those that are currently available and future ones. The decision model was developed based on the Hierarchical Decision Modeling (HDM) methodology. The model considers five major dimensions, social, technical, economic, environmental, and political (STEEP), and their related criteria and sub-criteria. The model was designed and developed by the author, and its elements' validation and evaluation were done by a large number of experts in the field of nuclear energy. The decision model was applied in evaluating five potential siting technologies and ranked the Natural Island as the best in comparison to Land-Based, Floating Plant, Artificial Island, and Semi-Embedded plant.

Life Limiting Issues for Long Term Operation of Nuclear Power Plants

International Nuclear Information System (INIS)

Esselman, Thomas; Gaertner, John

2012-01-01

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

Development of on-line operator aid system (OASYSTM) for nuclear power plants

International Nuclear Information System (INIS)

Kang, Ki Sig; Choi, Seong Soo; Kim, Han Gon; Chang, Soon Heung; Jeong, Hee Kyo; Yi, Chul Un

1994-01-01

In this paper, the development of On - line operator Aid SYStem (OASYS TM ) are discussed by focusing attention on the importance of the operator's role for nuclear power plants. The OASYS TM is under development to support the operator's decision making process and to enhance the safety of a nuclear power plant by providing the plant operators with timely and proper guideline during abnormal and emergency conditions. The OASYS TM has capabilities for the signal validation/management, the alarm processing, the failure diagnosis using abnormal operating procedures, and the dynamic tracking of emergency operating procedures using function restoration guidelines and optimal recovery guidelines with a series of complex logic steps covering a broad spectrum of event sequences. The proposed system is being implemented on a SUN-4/75 Workstation using C and Quintus TM prolog language. For verification studies a full-scope real-time simulator is being used. Test results show that the OASYS TM is capable of diagnosing a plant failure quickly and providing an operator guideline with fast response time. After verification the OASYS TM will be installed in the simulator II of Kori nuclear training center

A study on the operator's communication pattern characteristics under abnormal operating situation of nuclear power plants

International Nuclear Information System (INIS)

Kim, S. H.; Park, J.

2008-01-01

The quality of a probabilistic safety assessment (PSA) has become more important and a human reliability analysis (HRA) is known as a major contributor to the uncertainty of a PSA. As a part of enhancing the HRA quality, a study was initiated to find out characteristics of communication pattern and to evaluate communication quality of the operators of nuclear power plants. Korea Atomic Energy Research Institute (KAERI) is developing evaluation methods for the effect of human-induced events on risk/performance. This paper describes a study on the operator's communication pattern characteristics under abnormal operating situation of nuclear power plants. The study was carried out in four stages; 1) Video recording 2) Audio scripting 3) Message Classification 4) Communication Pattern Analysis. We recorded eight abnormal simulator training programs from Younggwang nuclear power plant training center. After that we performed message classification and carried out communication pattern analysis. We compared communication patterns of abnormal operating situation with emergency operating situation.As results of analysis, the role of SRO (senior reactor operator) under abnormal operating situation was decreased than the activities under emergency operating situation because each operator (reactor operator, turbine operator, safety supervisor) in main control room (MCR) performs the activity to control by himself with corresponding field engineers with his basic knowledge of the system. On the other hand, the operator's decision making processes and activities under abnormal operating situation were dramatically increased than the emergency operating situation. (authors)

The IDA cognitive model for the analysis of nuclear power plant operator response under accident conditions. Part I: problem solving and decision making model

International Nuclear Information System (INIS)

Smidts, C.; Shen, S.H.; Mosleh, A.

1997-01-01

This paper is the first of a series of papers describing IDA which is a cognitive model for analysing the behaviour of nuclear power plant operators under accident conditions. The domain of applicability of the model is a relatively constrained environment where behaviour is significantly influenced by high levels of training and explicit requirement to follow written procedures. IDA consists of a model for individual operator behaviour and a model for control room operating crew expanded from the individual model. The model and its derivatives such as an error taxonomy and data collection approach has been designed with ultimate objective of becoming a quantitative method for human reliability analysis (HRA) in probabilistic risk assessment (PRA). The present paper gives a description of the main components of IDA such as memory structure, goals, and problem solving and decision making strategies. It also identifies factors that are at the origin of transitions between goals or between strategies. These factors cover the effects of external conditions and psychological state of the operator. The description is generic at first and then made specific to the nuclear power plant environment and more precisely to abnormal conditions

Experimental studies of computerized procedures and team size in nuclear power plant operations

International Nuclear Information System (INIS)

Huang, F.-H.; Hwang, S.-L.

2009-01-01

The operation of a nuclear power plant is so complex that it requires teamwork. To support team performance, a system need to provide all team members integrated information displays as well as decision aids (e.g., computerized procedures). Two experiments were conducted to investigate the effects of computerized procedures and team size on operating performance. Forty-five participants were involved in the experiments. Each participant executed decision and action tasks to deal with alarm signals, while detecting occasional system errors in the interface. Results showed that effects of computerized procedures were significant on various performance indicators, such as operation time, operation errors, and learning effect, and that two operators would be a satisfactory size in the teamwork system providing computerized procedures

Review of operational aids for nuclear plant operators

International Nuclear Information System (INIS)

Kisner, R.A.

1983-01-01

Many approaches are being explored to improve the safety of nuclear plant operations. One approach is to supply high-quality, relevant information by means of computer-based diagnostic systems to assist plant operators in performing their operational and safety-related roles. The evaluation of operational aids to ensure safe plant operations is a necessary function of NRC. This work has two purposes: to collect limited data on a diversity of operational aids, and to provide a method for evaluating the safety implications of the functions of proposed operational aids. After a discussion of the method evaluation now under study, this paper outlines this data collection to date

Decision analysis for the siting of nuclear power plants: the relevance of multiattribute utility theory

International Nuclear Information System (INIS)

Keeney, R.L; Nair, K.

1975-01-01

The necessity for improved decision making concerning the siting and licensing of major power facilities has been accelerated in the past decade by the increased environmental consciousness of the public and by the energy crisis. These problems are exceedingly complex due to their multiple objective nature, the many interest groups, the long-range time horizons, and the inherent uncertainties of the potential impacts of any decision. Along with the relatively objective economic and engineering concerns, clearly the more subjective factors involving safety, environmental, and social issues are crucial to the problem. Hence, the professional judgments and knowledge of experts in these areas should be utilized in analyses of siting decisions. Likewise, the preferences of the general public, as consumers, the utility companies, as builders and operators of power plant facilities, and environmentalists and the government must be accounted for in analyzing power plant siting and licensing issues. We advocate an approach for formally articulating the experts' judgments and the decision makers' preferences, both of which are clearly subjective, and processing these along with the more objective considerations in a logical manner to acquire the implications for decision making. The appropriateness and application of decision analysis for power plant location decisions is discussed and illustrated. Emphasis is placed on the assessment of the decision maker's preferences and tradeoffs concerning multiple objectives. (U.S.)

Safety of Nuclear Power Plants: Commissioning and Operation. Specific Safety Requirements

International Nuclear Information System (INIS)

2017-01-01

This publication is a revision of IAEA Safety Standards Series No. NS-R-2, Safety of Nuclear Power Plants: Operation, and has been extended to cover the commissioning stage. It describes the requirements to be met to ensure the safe commissioning, operation, and transition from operation to decommissioning of nuclear power plants. Over recent years there have been developments in areas such as long term operation of nuclear power plants, plant ageing, periodic safety review, probabilistic safety analysis review and risk informed decision making processes. It became necessary to revise the IAEA’s Safety Requirements in these areas and to correct and/or improve the publication on the basis of feedback from its application by both the IAEA and its Member States. In addition, the requirements are governed by, and must apply, the safety objective and safety principles that are established in the IAEA Safety Standards Series No. SF-1, Fundamental Safety Principles. A review of Safety Requirements publications, initiated in 2011 following the accident in the Fukushima Daiichi nuclear power plant in Japan, revealed no significant areas of weakness but resulted in a small set of amendments to strengthen the requirements and facilitate their implementation. These are contained in the present publication.

Regulatory interventions necessitated by non-conservative operator decisions

International Nuclear Information System (INIS)

Ojha, D.; Chande, S.K.; Sharma, S.K.

2005-01-01

Presently, India has 15 nuclear power units in operation and 8 units under construction. Though the safety performance of the Nuclear Power Plants (NPPs) in India has been excellent, a few recent events indicate that conservative decision making process can possibly get affected by perceived production goals. In one of the events, a need for some maintenance work arose while reactor start-up was in progress. After it was realized that the maintenance would require considerable time, the proper course of action would have been to shutdown the reactor and add neutron poison to moderator to ensure sufficient sub criticality. This was not done, as it would have delayed the start up of the reactor on completion of maintenance. In another incident, an unintended slow increase in reactor power occurred due to the adjuster rods becoming inoperable on account of blowing-off of fuses in their power supply. Under this condition, the reactor should have been tripped which was not done. Further, the automatic addition of boron poison to the reactor was inhibited. Regulatory review showed that both the incidents were indicative of degradation in safety culture and reflected operator's overriding concern for keeping the units in operation. Appropriate corrective actions were taken to prevent recurrence of such events in the respective units as also in all other operating units of similar type. In the wake of improved production performance operators may develop a tendency to create new operational records and compete with other units. This aspect points out to a need for careful study of events to check the presence of any element of non-conservative decision-making and to identify leading indicators of degradation in safety performance. (author)

Use of decision trees for evaluating severe accident management strategies in nuclear power plants

Energy Technology Data Exchange (ETDEWEB)

Jae, Moosung [Hanyang Univ., Seoul (Korea, Republic of). Dept. of Nuclerar Engineering; Lee, Yongjin; Jerng, Dong Wook [Chung-Ang Univ., Seoul (Korea, Republic of). School of Energy Systems Engineering

2016-07-15

Accident management strategies are defined to innovative actions taken by plant operators to prevent core damage or to maintain the sound containment integrity. Such actions minimize the chance of offsite radioactive substance leaks that lead to and intensify core damage under power plant accident conditions. Accident management extends the concept of Defense in Depth against core meltdown accidents. In pressurized water reactors, emergency operating procedures are performed to extend the core cooling time. The effectiveness of Severe Accident Management Guidance (SAMG) became an important issue. Severe accident management strategies are evaluated with a methodology utilizing the decision tree technique.

The role of a multiagent organization in the management of nuclear plants operational objectives

International Nuclear Information System (INIS)

Papin, B.; Arnaud, G.; Fiche, Ch.; Dumas, M.

1998-01-01

The aim of the ESCRIME project, now reaching conclusions, was to optimize the collaboration between plant operators and computerized systems for the management of plant safety and availability. The requirement for putting such a collaboration into effective application was to clarify the operational strategies in order to enable a dialog between men and systems based on a ''shared representation'' of the plant operation. Thus a new vision of this operation, focusing on the completion of the plant fundamental objectives has been defined. This so-called means-ends strategy enables the simultaneous management of these objectives and provides explicit rules (priority...) to solve eventual conflicts (Physical interaction, sharing of resources...) apt to occur. The direct implementation of such strategies by the operators, using a dedicated man/machine interface, has made the object of the second phase of the ESCRIME project, already presented in LOEN in 1996. The third phase of the program, more prospective, aimed at finding an efficient way of sharing the management of plant objectives between the operator(s) and ''intelligent controllers'', preserving the role of the man in the decision loop and enabling him to maintain his awareness about the evolution of the plant. The multiagent organization has been identified as a promising way of sharing executive and decisive tasks between human and computerized agents. This organization, based on explicit ''social'' rules managing the negotiation between autonomous agents, appeared quite perfectly adapted to the management of conflicting objectives like in the means - ends strategy. The main problem to solve was, in fact, to check whether humans could be brought under this social organization in such a way as they could communicate and negotiate efficiently with the computerized agents. After a brief recall of the principles of the means - ends strategy for plant objectives management, this paper will detail the work made on

The operating organization for nuclear power plants. Safety guide

International Nuclear Information System (INIS)

2001-01-01

This Safety Guide was prepared under the IAEA programme for safety standards for nuclear power plants. The present publication is a revision of the IAEA Safety Guide on Management of Nuclear Power Plants for Safe Operation issued in 1984. It supplements Section 2 of the Safety Requirements publication on Safety of Nuclear Power Plants: Operation. Nuclear power technology is different from the customary technology of power generation from fossil fuel and by hydroelectric means. One major difference between the management of nuclear power plants and that of conventional generating plants is the emphasis that should be placed on nuclear safety, quality assurance, the management of radioactive waste and radiological protection, and the accompanying national regulatory requirements. This Safety Guide highlights the important elements of effective management in relation to these aspects of safety. The attention to be paid to safety requires that the management recognize that personnel involved in the nuclear power programme should understand, respond effectively to, and continuously search for ways to enhance safety in the light of any additional requirements socially and legally demanded of nuclear energy. This will help to ensure that safety policies that result in the safe operation of nuclear power plants are implemented and that margins of safety are always maintained. The structure of the organization, management standards and administrative controls should be such that there is a high degree of assurance that safety policies and decisions are implemented, safety is continuously enhanced and a strong safety culture is promoted and supported. The objective of this publication is to guide Member States in setting up an operating organization which facilitates the safe operation of nuclear power plants to a high level internationally. The second objective is to provide guidance on the most important organizational elements in order to contribute to a strong safety

The operating organization for nuclear power plants. Safety guide

International Nuclear Information System (INIS)

2005-01-01

This Safety Guide was prepared under the IAEA programme for safety standards for nuclear power plants. The present publication is a revision of the IAEA Safety Guide on Management of Nuclear Power Plants for Safe Operation issued in 1984. It supplements Section 2 of the Safety Requirements publication on Safety of Nuclear Power Plants: Operation. Nuclear power technology is different from the customary technology of power generation from fossil fuel and by hydroelectric means. One major difference between the management of nuclear power plants and that of conventional generating plants is the emphasis that should be placed on nuclear safety, quality assurance, the management of radioactive waste and radiological protection, and the accompanying national regulatory requirements. This Safety Guide highlights the important elements of effective management in relation to these aspects of safety. The attention to be paid to safety requires that the management recognize that personnel involved in the nuclear power programme should understand, respond effectively to, and continuously search for ways to enhance safety in the light of any additional requirements socially and legally demanded of nuclear energy. This will help to ensure that safety policies that result in the safe operation of nuclear power plants are implemented and that margins of safety are always maintained. The structure of the organization, management standards and administrative controls should be such that there is a high degree of assurance that safety policies and decisions are implemented, safety is continuously enhanced and a strong safety culture is promoted and supported. The objective of this publication is to guide Member States in setting up an operating organization which facilitates the safe operation of nuclear power plants to a high level internationally. The second objective is to provide guidance on the most important organizational elements in order to contribute to a strong safety

The operating organization for nuclear power plants. Safety guide

International Nuclear Information System (INIS)

2004-01-01

This Safety Guide was prepared under the IAEA programme for safety standards for nuclear power plants. The present publication is a revision of the IAEA Safety Guide on Management of Nuclear Power Plants for Safe Operation issued in 1984. It supplements Section 2 of the Safety Requirements publication on Safety of Nuclear Power Plants: Operation. Nuclear power technology is different from the customary technology of power generation from fossil fuel and by hydroelectric means. One major difference between the management of nuclear power plants and that of conventional generating plants is the emphasis that should be placed on nuclear safety, quality assurance, the management of radioactive waste and radiological protection, and the accompanying national regulatory requirements. This Safety Guide highlights the important elements of effective management in relation to these aspects of safety. The attention to be paid to safety requires that the management recognize that personnel involved in the nuclear power programme should understand, respond effectively to, and continuously search for ways to enhance safety in the light of any additional requirements socially and legally demanded of nuclear energy. This will help to ensure that safety policies that result in the safe operation of nuclear power plants are implemented and that margins of safety are always maintained. The structure of the organization, management standards and administrative controls should be such that there is a high degree of assurance that safety policies and decisions are implemented, safety is continuously enhanced and a strong safety culture is promoted and supported. The objective of this publication is to guide Member States in setting up an operating organization which facilitates the safe operation of nuclear power plants to a high level internationally. The second objective is to provide guidance on the most important organizational elements in order to contribute to a strong safety

Plant operator performance evaluation system

International Nuclear Information System (INIS)

Ujita, Hiroshi; Fukuda, Mitsuko; Kubota, Ryuji.

1989-01-01

A plant operator performance evaluation system to analyze plant operation records during accident training and to identify and classify operator errors has been developed for the purpose of supporting realization of a training and education system for plant operators. A knowledge engineering technique was applied to evaluation of operator behavior by both even-based and symptom-based procedures, in various situations including event transition due to multiple failures or operational errors. The system classifies the identified errors as to their single and double types based on Swain's error classification and the error levels reflecting Rasmussen's cognitive level, and it also evaluates the effect of errors on plant state and then classifies error influence, using 'knowledge for phenomena and operations', as represented by frames. It has additional functions for analysis of error statistics and knowledge acquisition support of 'knowledge for operations'. The system was applied to a training analysis for a scram event in a BWR plant, and its error analysis function was confirmed to be effective by operational experts. (author)

Cognitive skills and nuclear power plant operational decision-making

International Nuclear Information System (INIS)

Schoenfeld, Isabelle

1998-01-01

The author reports a project research which aimed at identifying cognitive skills required for severe accident management. It is based on an analytical model of decision making for severe accident conditions. Moreover, scenarios were developed to reveal specific decision making difficulties and to test cognitive skills associated with each of the model's elements. The model used to identify cognitive skills comprised six general processes to describe decision-making performance: monitor/detect, interpret current state, determine implications, plan, control, feedback. For each of these processes, situational factors, cognitive limitations and biases, individual cognitive skills and team cognitive skills have been identified

NPPO-TINA: An expert system acting as catalyst for decision-making processes of the reactor operator

International Nuclear Information System (INIS)

Gieci, A.; Gyarfas, F.

1991-01-01

The prototype of the NPPO-TINA expert system (Nuclear Power Plant Operation-Transparent Inference Architecture) is described. This system has been developed to support the entire decision-making intellectual activity in the control of complex technological processes. One of the ways leading to human-machine symbiosis in the integrated cognitive system is outlined. The starting model of the situation in which the operator's problem-solving task begins is described. The characteristics of human behavior in decision-making are analyzed, and the moments are explained of the most suitable use of the expert system to support the whole intellectual activity, in knowledge-based decision-making by way of problem solving. The TINA environment for the formation of expert systems is described, including the hierarchic dynamic inference control. The process of building up the NPPO-TINA expert system is outlined, and the results of testing the system prototype on the problem of an accident of the nuclear power plant primary circuit due to a failure of the coolant make-up pumps are given. (Z.S.). 10 figs., 11 refs

Research on operation support system for nuclear power plants

International Nuclear Information System (INIS)

Wakabayashi, Jiro

1989-01-01

Nuclear power plants are the typical, complex, large scale engineering system, and at the time of accidents, there is the possibility to extend disasters to wide range beyond borders, therefore, it is the feature that the requirement for their reliability and safety is much severe as compared with other engineering systems. The fact that human errors become the major cause of large accidents is in common in large scale engineering systems, and the development of the operation support system for preventing it has become an important research subject. Also the research on design support system and maintenance support system is in progress to prevent human errors. Operation support system is composed of diagnostic system, operation guide system, man-machine interface and knowledge data base, and throughout these, the research on the human errors arising in the process of human decision making becomes the basis. Rasmussen's model for decision making, the classification of human errors and the reliability analysis for men, the factors affecting human errors, the acquisition of knowledge, the compilation and management of knowledge data base, the diagnostic system, operation guide system and man-machine interface are described. (K.I.)

Kvanefjeld refinery pilot plant operations

International Nuclear Information System (INIS)

Krebs, Damien; Furfaro, Domenic

2016-01-01

Greenland Minerals and Energy is a junior project development company which is listed on the Australian Stock Exchange (asx:GGG). It is developing the Kvanefjeld rare earth and uranium project located in the southern tip of Greenland. The project has completed a Feasibility Study and is currently in the permitting phase. Last year was a busy time for the company as it completed a Feasibility Study, a mining licence application (draft submitted in December 2015) and pilot plant operations. Beneficiation pilot plant operations were completed at GTK in Finland in April 2015. This pilot plant treated approximately 30 tonnes of ore to producing almost 2 tonnes of rare earth mineral concentrate. Later in the year a hydrometallurgical pilot plant was performed which mimicked the Refinery process. This pilot plant was performed at Outotec’s Pori Research laboratories in Finland from September till October 2015. The pilot plant treated approximately 200 kilograms of concentrate over 4 split operating campaigns. Each campaign was performed to focus on the performance of a specific part of the refinery flowsheet. This allowed for full operating focus on a single unit operation to ensure that it was operating correctly. The pilot plant operations were quite successful with no major issues with the flowsheet identified through continuous operation. Some fine tuning of conditions was required to ensure adequate removal of impurities was performed with recycle streams incorporated. Overall the leach extractions observed in the pilot plant exceeded the design assumptions in the Feasibility Study. These programs were partially funded by the EURARE program. The EURARE program aims to encourage the sustainable development of European based rare earth projects. This has the goal of allowing Europe to become less reliant on importation of these key raw materials. The professionalism and performance of both GTK and Outotec contributed significantly to the success of the pilot plant

Plant security during decommissioning; challenges and lessons learned from German phase out decision

International Nuclear Information System (INIS)

Renner, Andrea; Esch, Markus

2013-01-01

Purpose of this paper is to point out the security challenges that may occur during the decommissioning, based on the issues and lessons learned from the German phase out decision. Though national regulations may be different in other countries the basic problems and issues will be the same. Therefore presented solutions will be applicable in other countries as well. The radioactive material remaining at the NPP during decommissioning has the most influence on how the security measures have to be designed. The radioactive material defines the risk potential of the plant and this determines the needed security level. The following aspects have been challenging in Germany: - Scenarios varying from those, used for plants in operation, due to changed operating conditions - Spent fuel will stay in the spent fuel pool for a quite long period before it can be removed from the plant. Risk potential of the plant stays high and requires a high level of security measures - Security measures according to the existing operating license have to stay in place as they are, unless the first license for decommissioning is given respective the spent fuel is removed from the plant site. This even led to the question if improvements of security measures, planned and announced with focus on a plant remaining in operation for another couple of years, need to be done although they will not be required after removing the spent fuel from the plant. A further important aspect for the security design is the fact that a plant under decommissioning has completely different and strongly varying operating procedures, compared to the stable ones of an operating plant. This leads to different needs concerning workspace, infrastructure on plant site, access to buildings etc. An optimized and highly flexible security concept is needed to ensure an adequate level of security as well as an efficient decommissioning. A deep analysis of the vital plant functions, depending on the different

How do strategic decisions and operative practices affect operating room productivity?

Science.gov (United States)

Peltokorpi, Antti

2011-12-01

Surgical operating rooms are cost-intensive parts of health service production. Managing operating units efficiently is essential when hospitals and healthcare systems aim to maximize health outcomes with limited resources. Previous research about operating room management has focused on studying the effect of management practices and decisions on efficiency by utilizing mainly modeling approach or before-after analysis in single hospital case. The purpose of this research is to analyze the synergic effect of strategic decisions and operative management practices on operating room productivity and to use a multiple case study method enabling statistical hypothesis testing with empirical data. 11 hypotheses that propose connections between the use of strategic and operative practices and productivity were tested in a multi-hospital study that included 26 units. The results indicate that operative practices, such as personnel management, case scheduling and performance measurement, affect productivity more remarkably than do strategic decisions that relate to, e.g., units' size, scope or academic status. Units with different strategic positions should apply different operative practices: Focused hospital units benefit most from sophisticated case scheduling and parallel processing whereas central and ambulatory units should apply flexible working hours, incentives and multi-skilled personnel. Operating units should be more active in applying management practices which are adequate for their strategic orientation.

Safety of Nuclear Power Plants: Commissioning and Operation. Specific Safety Requirements (French Edition)

International Nuclear Information System (INIS)

2016-01-01

This publication describes the requirements to be met to ensure the safe operation of nuclear power plants. It takes into account developments in areas such as long term operation of nuclear power plants, plant ageing, periodic safety review, probabilistic safety analysis and risk informed decision making processes. In addition, the requirements are governed by, and must apply, the safety objective and safety principles that are established in the IAEA Safety Standards Series No. SF-1, Fundamental Safety Principles. A review of Safety Requirements publications was commenced in 2011 following the accident in the Fukushima Daiichi nuclear power plant in Japan. The review revealed no significant areas of weakness and resulted in just a small set of amendments to strengthen the requirements and facilitate their implementation, which are contained in the present publication.

Balancing effluent quality, economic cost and greenhouse gas emissions during the evaluation of (plant-wide) control/operational strategies in WWTPs

DEFF Research Database (Denmark)

Flores Alsina, Xavier; Arnell, Magnus; Amerlinck, Youri

2014-01-01

The objective of this paper was to show the potential additional insight that result from adding greenhouse gas (GHG) emissions to plant performance evaluation criteria, such as effluent quality (EQI) and operational cost (OCI) indices, when evaluating (plant-wide) control/operational strategies ...... evaluation criteria to compare and evaluate (plant-wide) control strategies in a WWTP for more informed operational decision making. © 2013 Elsevier B.V.......The objective of this paper was to show the potential additional insight that result from adding greenhouse gas (GHG) emissions to plant performance evaluation criteria, such as effluent quality (EQI) and operational cost (OCI) indices, when evaluating (plant-wide) control/operational strategies...

Online condition monitoring to enable extended operation of nuclear power plants

International Nuclear Information System (INIS)

Meyer, Ryan Michael; Bond, Leonard John; Ramuhalli, Pradeep

2012-01-01

Safe, secure, and economic operation of nuclear power plants will remain of strategic significance. New and improved monitoring will likely have increased significance in the post-Fukushima world. Prior to Fukushima, many activities were already underway globally to facilitate operation of nuclear power plants beyond their initial licensing periods. Decisions to shut down a nuclear power plant are mostly driven by economic considerations. Online condition monitoring is a means to improve both the safety and economics of extending the operating lifetimes of nuclear power plants, enabling adoption of proactive aging management. With regard to active components (e.g., pumps, valves, motors, etc.), significant experience in other industries has been leveraged to build the science base to support adoption of online condition-based maintenance and proactive aging management in the nuclear industry. Many of the research needs are associated with enabling proactive management of aging in passive components (e.g., pipes, vessels, cables, containment structures, etc.). This paper provides an overview of online condition monitoring for the nuclear power industry with an emphasis on passive components. Following the overview, several technology/knowledge gaps are identified, which require addressing to facilitate widespread online condition monitoring of passive components. (author)

Management of nuclear power plants for safe operation

International Nuclear Information System (INIS)

1984-01-01

This Guide identifies the main objectives and responsibilities of management with respect to safe operation of nuclear power plants. The Guide discusses the factors to be considered in structuring the operating organization to meet these objectives, to establish the management programmes that assure the safety tasks are performed, and to see that the services and facilities needed to accomplish the tasks are available. The Guide is primarily addressed to safety matters directly related to the operating phase. It assumes, in other words, that the safety aspects of siting, design, manufacturing and construction have been resolved. However, it also covers the interrelationships between operations and design, construction and commissioning, including the involvement of the operating organization in appropriate reviews of safety issues with reference to the future operating phase. The Guide is mainly restricted to matters of principle in relation to management-level decision making aimed at establishing safety policies. It is therefore not suitable for implementing such policies at the operational level. The IAEA Codes of Practice and Safety Guides provide detailed guidance for the latter purpose in those areas considered appropriate

Gas-fired power plants: Investment timing, operating flexibility and CO2 capture

International Nuclear Information System (INIS)

Fleten, Stein-Erik; Naesaekkaelae, Erkka

2010-01-01

We analyze investments in gas-fired power plants based on stochastic electricity and natural gas prices. A simple but realistic two-factor model is used for price processes, enabling analysis of the value of operating flexibility, the opportunity to abandon the capital equipment, as well as finding thresholds for energy prices for which it is optimal to enter into the investment. We develop a method to compute upper and lower bounds on plant values and investment threshold levels. Our case study uses representative power plant investment and operations data, and historical forward prices from well-functioning energy markets. We find that when the decision to build is considered, the abandonment option does not have significant value, whereas the operating flexibility and time-to-build option have significant effect on the building threshold. Furthermore, the joint value of the operating flexibility and the abandonment option is much smaller than the sum of their separate values, because both are options to shut down. The effects of emission costs on the value of installing CO 2 capture technology are also analyzed.

Simulation-based decision support for evaluating operational plans

Directory of Open Access Journals (Sweden)

Johan Schubert

2015-12-01

Full Text Available In this article, we describe simulation-based decision support techniques for evaluation of operational plans within effects-based planning. Using a decision support tool, developers of operational plans are able to evaluate thousands of alternative plans against possible courses of events and decide which of these plans are capable of achieving a desired end state. The objective of this study is to examine the potential of a decision support system that helps operational analysts understand the consequences of numerous alternative plans through simulation and evaluation. Operational plans are described in the effects-based approach to operations concept as a set of actions and effects. For each action, we examine several different alternative ways to perform the action. We use a representation where a plan consists of several actions that should be performed. Each action may be performed in one of several different alternative ways. Together these action alternatives make up all possible plan instances, which are represented as a tree of action alternatives that may be searched for the most effective sequence of alternative actions. As a test case, we use an expeditionary operation with a plan of 43 actions and several alternatives for these actions, as well as a scenario of 40 group actors. Decision support for planners is provided by several methods that analyze the impact of a plan on the 40 actors, e.g., by visualizing time series of plan performance. Detailed decision support for finding the most influential actions of a plan is presented by using sensitivity analysis and regression tree analysis. Finally, a decision maker may use the tool to determine the boundaries of an operation that it must not move beyond without risk of drastic failure. The significant contribution of this study is the presentation of an integrated approach for evaluation of operational plans.

Organizing nuclear power plant operation

International Nuclear Information System (INIS)

Adams, H.W.; Rekittke, K.

1987-01-01

With the preliminary culmination in the convoy plants of the high standard of engineered safeguards in German nuclear power plants developed over the past twenty years, the interest of operators has now increasingly turned to problems which had not been in the focus of attention before. One of these problems is the organization of nuclear power plant operation. In order to enlarge the basis of knowledge, which is documented also in the rules published by the Kerntechnischer Ausschuss (Nuclear Technology Committee), the German Federal Minister of the Interior has commissioned a study of the organizational structures of nuclear power plants. The findings of that study are covered in the article. Two representative nuclear power plants in the Federal Republic of Germany were selected for the study, one of them a single-unit plant run by an independent operating company in the form of a private company under German law (GmbH), the other a dual-unit plant operated as a dependent unit of a utility. The two enterprises have different structures of organization. (orig.) [de

Nuclear power plant operator licensing

International Nuclear Information System (INIS)

1997-01-01

The guide applies to the nuclear power plant operator licensing procedure referred to the section 128 of the Finnish Nuclear Energy Degree. The licensing procedure applies to shift supervisors and those operators of the shift teams of nuclear power plant units who manipulate the controls of nuclear power plants systems in the main control room. The qualification requirements presented in the guide also apply to nuclear safety engineers who work in the main control room and provide support to the shift supervisors, operation engineers who are the immediate superiors of shift supervisors, heads of the operational planning units and simulator instructors. The operator licensing procedure for other nuclear facilities are decided case by case. The requirements for the basic education, work experience and the initial, refresher and complementary training of nuclear power plant operating personnel are presented in the YVL guide 1.7. (2 refs.)

Operation monitor for plant equipment

International Nuclear Information System (INIS)

Kondo, Tetsufumi; Kanemoto, Shigeru.

1991-01-01

In a nuclear power plant, states of each of equipment in the plant are monitored accurately even under such a operation condition that the power is changed. That is, the fundamental idea is based on a model comparison method. A deviation between an output signal upon normal plant state obtained in a forecasting model device and that of the objective equipment in the plant are compared with a predetermined value. The result of the comparison is inputted to an alarm device to alarm the abnormality of the states of the equipment to an operator. The device of the present invention thus constituted can monitor the abnormality of the operation of equipment accurately even under such a condition that a power level fluctuates. As a result, it can remarkably contribute to mitigate operator's monitoring operation under the condition such as during load following operation. (I.S.)

Conduct of Operations at Nuclear Power Plants. Safety Guide (Spanish Edition); Realizacion de operaciones en centrales nucleares. Guia de seguridad

Energy Technology Data Exchange (ETDEWEB)

NONE

2012-04-15

This Safety Guide identifies the main responsibilities and practices of nuclear power plant (NPP) operations departments in relation to their responsibility for the safe functioning of the plant. The guide presents the factors to be considered in structuring the operations department of an NPP; setting high standards of performance; making safety related decisions in an effective manner; conducting control room and field activities in a thorough and professional manner; and maintaining an NPP within established operational limits and conditions. Contents: 1. Introduction; 2. Management and organization of plant operations; 3. Shift complement and functions; 4. Shift routines and operating practices; 5. Control of equipment and plant status; 6. Operations equipment and operator aids; 7. Work control and authorization.

An analyser for power plant operations

International Nuclear Information System (INIS)

Rogers, A.E.; Wulff, W.

1990-01-01

Safe and reliable operation of power plants is essential. Power plant operators need a forecast of what the plant will do when its current state is disturbed. The in-line plant analyser provides precisely this information at relatively low cost. The plant analyser scheme uses a mathematical model of the dynamic behaviour of the plant to establish a numerical simulation. Over a period of time, the simulation is calibrated with measurements from the particular plant in which it is used. The analyser then provides a reference against which to evaluate the plant's current behaviour. It can be used to alert the operator to any atypical excursions or combinations of readings that indicate malfunction or off-normal conditions that, as the Three Mile Island event suggests, are not easily recognised by operators. In a look-ahead mode, it can forecast the behaviour resulting from an intended change in settings or operating conditions. Then, when such changes are made, the plant's behaviour can be tracked against the forecast in order to assure that the plant is behaving as expected. It can be used to investigate malfunctions that have occurred and test possible adjustments in operating procedures. Finally, it can be used to consider how far from the limits of performance the elements of the plant are operating. Then by adjusting settings, the required power can be generated with as little stress as possible on the equipment. (6 figures) (Author)

Safety margins of operating reactors. Analysis of uncertainties and implications for decision making

International Nuclear Information System (INIS)

2003-01-01

Maintaining safety in the design and operation of nuclear power plants (NPPs) is a very important task under the conditions of a challenging environment, affected by the deregulated electricity market and implementation of risk informed regulations. In Member States, advanced computer codes are widely used as safety analysis tools in the framework of licensing of new NPP projects, safety upgrading programmes of existing NPPs, periodic safety reviews, renewal of operating licences, use of the safety margins for reactor power uprating, better utilization of nuclear fuel and higher operational flexibility, for justification of lifetime extensions, development of new emergency operating procedures, analysis of operational events, and development of accident management programmes. The issue of inadequate quality of safety analysis is becoming important due to a general tendency to use advanced tools for better establishment and utilization of safety margins, while the existence of such margins assure that NPPs operate safely in all modes of operation and at all times. The most important safety margins relate to physical barriers against release of radioactive material, such as fuel matrix and fuel cladding, reactor coolant system boundary, and the containment. Typically, safety margins are determined with use of computational tools for safety analysis. Advanced best estimate computer codes are suggested e.g. in the IAEA Safety Guide on Safety Assessment and Verification for Nuclear Power Plants to be used for current safety analysis. Such computer codes require their careful application to avoid unjustified reduction in robustness of the reactor safety. The issue of uncertainties in safety analyses and their impact on evaluation of safety margins is addressed in a number of IAEA guidance documents, in particular in the Safety Report on Accident Analysis for Nuclear Power Plants. It is also discussed in various technical meetings and workshops devoted to this area. The

A quantitative impact analysis of sensor failures on human operator's decision making in nuclear power plants

International Nuclear Information System (INIS)

Seong, Poong Hyun

2004-01-01

In emergency or accident situations in nuclear power plants, human operators take important roles in generating appropriate control signals to mitigate accident situation. In human reliability analysis (HRA) in the framework of probabilistic safety assessment (PSA), the failure probabilities of such appropriate actions are estimated and used for the safety analysis of nuclear power plants. Even though understanding the status of the plant is basically the process of information seeking and processing by human operators, it seems that conventional HRA methods such as THERP, HCR, and ASEP does not pay a lot of attention to the possibilities of providing wrong information to human operators. In this paper, a quantitative impact analysis of providing wrong information to human operators due to instrument faults or sensor failures is performed. The quantitative impact analysis is performed based on a quantitative situation assessment model. By comparing the situation in which there are sensor failures and the situation in which there are not sensor failures, the impact of sensor failures can be evaluated quantitatively. It is concluded that the impact of sensor failures are quite significant at the initial stages, but the impact is gradually reduced as human operators make more and more observations. Even though the impact analysis is highly dependent on the situation assessment model, it is expected that the conclusions made based on other situation assessment models with be consistent with the conclusion made in this paper. (author)

Development of a New Safety Culture Assessment Method for Nuclear Power Plants (NPPs) (Decision support system for an OPR-1000 type power plant)

Energy Technology Data Exchange (ETDEWEB)

Kim, Yo Chan; Jung, Won Dea [Korea Atomic Energy Institute, Daejeon (Korea, Republic of)

2014-08-15

To support operators in the diagnosis of abnormal operating procedures (AOPs), we developed a decision support system for an OPR-1000 type power plant. This system aids operators who identify abnormal situations from annunciated alarms using three functions: an AOP flowchart, AOP search, and alarm simulation. This paper introduces the developed system, compares the characteristics of the functions in the system, and discusses the strength of this approach compared with other previous research. It is expected that the advanced functions may elevate the performance and reliability of operators who manage abnormal situations.

Development of a New Safety Culture Assessment Method for Nuclear Power Plants (NPPs) (Decision support system for an OPR-1000 type power plant)

International Nuclear Information System (INIS)

Kim, Yo Chan; Jung, Won Dea

2014-01-01

To support operators in the diagnosis of abnormal operating procedures (AOPs), we developed a decision support system for an OPR-1000 type power plant. This system aids operators who identify abnormal situations from annunciated alarms using three functions: an AOP flowchart, AOP search, and alarm simulation. This paper introduces the developed system, compares the characteristics of the functions in the system, and discusses the strength of this approach compared with other previous research. It is expected that the advanced functions may elevate the performance and reliability of operators who manage abnormal situations

NPP operator support in decision making - diagnostics of the operation failures using fuzzy logic

International Nuclear Information System (INIS)

Petruzela, I.

2000-01-01

In large complex systems such as nuclear power plants (NPP) and chemical industry plants, various subsystems fulfil the needs of process control and safety. Continued operation of these systems has both economic and safety implications. Electric utilities seek continuously to improve the operation of power generating stations. The improvement in the NPP Dukovany (4 x 440 MW) is related to the introduction of the plant to frequency control, meaning that the plant is operated not only in the base load operational mode but in the load follow mode as well. To achieve the improvement of plant operation, it was necessary to provide modifications to the plant control system, plant information system and diagnostics. This chapter deals with utilisation of artificial intelligence (AI) methods in implementation of these plant modifications. (orig.)

Nurse managers' decision-making in daily unit operation in peri-operative settings: a cross-sectional descriptive study.

Science.gov (United States)

Siirala, Eriikka; Peltonen, Laura-Maria; Lundgrén-Laine, Heljä; Salanterä, Sanna; Junttila, Kristiina

2016-09-01

To describe the tactical and the operational decisions made by nurse managers when managing the daily unit operation in peri-operative settings. Management is challenging as situations change rapidly and decisions are constantly made. Understanding decision-making in this complex environment helps to develop decision support systems to support nurse managers' operative and tactical decision-making. Descriptive cross-sectional design. Data were collected from 20 nurse managers with the think-aloud method during the busiest working hours and analysed using thematic content analysis. Nurse managers made over 700 decisions; either ad hoc (n = 289), near future (n = 268) or long-term (n = 187) by nature. Decisions were often made simultaneously with many interruptions. Ad hoc decisions covered staff allocation, ensuring adequate staff, rescheduling surgical procedures, confirmation tangible resources and following-up the daily unit operation. Decisions in the near future were: planning of surgical procedures and tangible resources, and planning staff allocation. Long-term decisions were: human recourses, nursing development, supplies and equipment, and finances in the unit. Decision-making was vulnerable to interruptions, which sometimes complicated the managing tasks. The results can be used when planning decision support systems and when defining the nurse managers' tasks in peri-operative settings. © 2016 John Wiley & Sons Ltd.

Safety of Nuclear Power Plants: Commissioning and Operation. Specific Safety Requirements (Arabic Edition)

International Nuclear Information System (INIS)

2017-01-01

This publication is a revision of IAEA Safety Standards Series No. NS-R-2, Safety of Nuclear Power Plants: Operation, and has been extended to cover the commissioning stage. It describes the requirements to be met to ensure the safe commissioning, operation, and transition from operation to decommissioning of nuclear power plants. Over recent years there have been developments in areas such as long term operation of nuclear power plants, plant ageing, periodic safety review, probabilistic safety analysis review and risk informed decision making processes. It became necessary to revise the IAEA’s Safety Requirements in these areas and to correct and/or improve the publication on the basis of feedback from its application by both the IAEA and its Member States. In addition, the requirements are governed by, and must apply, the safety objective and safety principles that are established in the IAEA Safety Standards Series No. SF-1, Fundamental Safety Principles. A review of Safety Requirements publications, initiated in 2011 following the accident in the Fukushima Daiichi nuclear power plant in Japan, revealed no significant areas of weakness but resulted in a small set of amendments to strengthen the requirements and facilitate their implementation. These are contained in the present publication.

Plant operator selection system for evaluating employment candidates' potential for success in electric power plant operations positions

International Nuclear Information System (INIS)

Dunnette, M.D.

1982-01-01

The Plant Operator Selection System is a battery of tests and questionnaires that can be administered to job candidates in less than three hours. Various components of the battery measure what a job candidate has accomplished in previous educational and work situations, how well a candidate compares with others on a number of important aptitudes or abilities, and whether or not a candidate possesses the kind of personal stability required in power plant operations positions. A job candidate's answers to the tests and questionnaires of the Plant Operator Selection System are scored and converted to an OVERALL POTENTIAL INDEX. Values of the OVERALL POTENTIAL INDEX [OPI] range between 0 and 15. Candidates with high OPI values are much more likely to become effective and successful plant operators than candidates with low OPI values. It is possible to estimate the financial advantages to a company of using the Plant Operator Selection System in evaluating candidates for plant operations jobs

Operating household wastewater treatment plants in the light of binding quality standards for wastewater discharged to water bodies or to soil

Directory of Open Access Journals (Sweden)

Jawecki Bartosz

2017-03-01

Full Text Available The study presents the legal requirements concerning the quality of wastewater discharged to waterbodies and to soil after treatment in household wastewater treatment plants located in agglomerations or outside them. The procedure of stopping the operation of a household treatment plant that doesn’t meet the statutory wastewater treatment efficiency was presented. The decision ordering to stop the use of a household wastewater treatment plant has to be preceded by a decision ordering to take measures to limit its adverse impact on the environment. The clarification procedure has to determine the adverse impact on the environment in a doubtless manner and it has to be reflected in the documentation. The assessment of adverse impact should take into account the binding standards of use of the environment. Stopping the operation of a household wastewater treatment plant may result in issuing a decision ordering the user to connect to the sanitary sewage system.

Modeling Operating Modes during Plant Life Cycle

DEFF Research Database (Denmark)

Jørgensen, Sten Bay; Lind, Morten

2012-01-01

Modelling process plants during normal operation requires a set a basic assumptions to define the desired functionalities which lead to fullfillment of the operational goal(-s) for the plant. However during during start-up and shut down as well as during batch operation an ensemble of interrelated...... modes are required to cover the whole operational window of a processs plant including intermediary operating modes. Development of such an model ensemble for a plant would constitute a systematic way of defining the possible plant operating modes and thus provide a platform for also defining a set...... of candidate control structures. The present contribution focuses on development of a model ensemble for a plant with an illustartive example for a bioreactor. Starting from a functional model a process plant may be conceptually designed and qualitative operating models may be developed to cover the different...

Spill operation system decision support system

International Nuclear Information System (INIS)

Clark, R.

1992-01-01

The MSRC Spill Operation System (SOS) is a tool for the support of decision-making at the time of a catastrophic oil spill. SOS provides MSRC decision-makers with access to information about the source of the spill, the spill environment, and the availability of spill response resources. This system is designed to meet the information needs of a Response Supervisor, an Environmental Advisor, Logistics/Maintenance Supervisor, Operations Supervisor, and the MSRC Regional General Manager. The SOS project Objectives are: (1) integrate currently available data, systems, and technologies; (2) develop an application that effectively supports mobilized operations and can be adapted to support normal operations; (3) ensure that the development of computer applications is driven by user needs and not by technology; and (4) coordinate with government and other industry organizations to avoid duplication of effort. Design Objectives for SOS are: (1) centralize management information storage while decentralizing decision making capabilities; (2) boost User confidence by providing a system that is easy to learn, easy to use, and is open-quotes Sailor Proofclose quotes; and (3) use visualization technology in providing spill related information. This approach includes the use of Geographic Information System (GIS) technology for maps and geographically associated resource; and support MSRC's concept of operation which includes - a swift notification of response personnel; fast mobilization of response resources; and accurate tracking of resources during a spill. MSRC is organized into five responsibility regions

Ergonomics and risk management in high risk organizations: nuclear power plant operator decision making; A ergonomia e a gestao de risco em organizacoes que lidam com tecnologias perigosas: tomada de decisao de operadores de usinas nucleares

Energy Technology Data Exchange (ETDEWEB)

Carvalho, Paulo Victor Rodrigues de

2003-08-15

Nuclear power plants are high hazard environments where emergency situations can have devastating effects. The operator crew has the ultimate responsibility to control the energy production process with safety. The outcome of a crisis is consequently dependent on the crew's judgement, decision making and situation awareness. In such way we should know how operators make their decisions in order to develop safety strategies. The aim of this thesis is to examine the cognitive processes through which operators make decisions when dealing with micro incidents during their actual work, and to determine whether they use a naturalistic or normative decision making strategy. That is, do they try to recognize the micro incident as familiar and base decisions on condition-action rules (naturalistic), or do they need to concurrently compare and contrast options before selecting the best possible (normative). The method employed for data collection was the Cognitive Task Analysis (CTA) and Ergonomic Work Analysis (EWA). The main findings of this thesis were that decision making is primarily based on naturalistic strategies, such as condition-action rules and recognition. In new situations rules are created ad hoc. These rules appear derived from experience and training rather than from Standard Operating Procedures and contrast normative competence standards used by nuclear industry. (author)

Recruitment training and licensing of operating personnel for nuclear power plants

International Nuclear Information System (INIS)

Palabrica, R.J.

1979-01-01

This article covers the step-by-step and most rigid recruitment, training, and licensing procedures undertaken in the selection for personnel involved in nuclear power plant operations. These procedures are true to all countries. However, for developing countries such as the Philippines, a bachelor's degree may be required as compared with the U.S. wherein a high school diploma is the minimum requirement. Because of the complexity of a nuclear facility, the work will require highly capable individuals with mature judgement who can render correct decisions even under highly stressed conditions. Thus during the selection and recruitment of applicants for the operator position, they are not only given aptitude tests but are also subjected to a series of psychological examintions. Once they are accepted, they are made to undergo a comprehensive and in-depth training to ensure that they will be capable of operating the nuclear power plant safely and effectively. Finally, those prospective operators have to pass licensing examinations in order to prove their competence and skills. Retraining programs follow after their training to maintain their skills. (RTD)

Risk-based decision analysis for groundwater operable units

International Nuclear Information System (INIS)

Chiaramonte, G.R.

1995-01-01

This document proposes a streamlined approach and methodology for performing risk assessment in support of interim remedial measure (IRM) decisions involving the remediation of contaminated groundwater on the Hanford Site. This methodology, referred to as ''risk-based decision analysis,'' also supports the specification of target cleanup volumes and provides a basis for design and operation of the groundwater remedies. The risk-based decision analysis can be completed within a short time frame and concisely documented. The risk-based decision analysis is more versatile than the qualitative risk assessment (QRA), because it not only supports the need for IRMs, but also provides criteria for defining the success of the IRMs and provides the risk-basis for decisions on final remedies. For these reasons, it is proposed that, for groundwater operable units, the risk-based decision analysis should replace the more elaborate, costly, and time-consuming QRA

Nuclear power plant operating experience, 1976

International Nuclear Information System (INIS)

1977-11-01

This report is the third in a series of reports issued annually that summarize the operating experience of U.S. nuclear power plants in commercial operation. Power generation statistics, plant outages, reportable occurrences, fuel element performance, occupational radiation exposure and radioactive effluents for each plant are presented. Summary highlights of these areas are discussed. The report includes 1976 data from 55 plants--23 boiling water reactor plants and 32 pressurized water reactor plants

Systems with artificial intelligence in nuclear power plant operation

International Nuclear Information System (INIS)

Bastl, W.; Felkel, L.

1989-01-01

The authors first summarize some developments made by GRS teams which can be regarded as the precursors of systems with artificial intelligence, and explain the basic characteristics of artificial intelligence, referring in particular to possible applications in nuclear engineering. The systems described are arranged in four groups according to applicability as follows: plant diagnosis and failure analysis, information systems and operating systems, control systems, assessment and decision aids. The working principle of the systems is explained by some examples giving details of the database and the interference processes. (orig./DG) [de

Environmental impact assessment of coal power plants in operation

Directory of Open Access Journals (Sweden)

Bartan Ayfer

2017-01-01

Full Text Available Coal power plants constitute an important component of the energy mix in many countries. However, coal power plants can cause several environmental risks such as: climate change and biodiversity loss. In this study, a tool has been proposed to calculate the environmental impact of a coal-fired thermal power plant in operation by using multi-criteria scoring and fuzzy logic method. We take into account the following environmental parameters in our tool: CO, SO2, NOx, particulate matter, fly ash, bottom ash, the cooling water intake impact on aquatic biota, and the thermal pollution. In the proposed tool, the boundaries of the fuzzy logic membership functions were established taking into account the threshold values of the environmental parameters which were defined in the environmental legislation. Scoring of these environmental parameters were done with the statistical analysis of the environmental monitoring data of the power plant and by using the documented evidences that were obtained during the site visits. The proposed method estimates each environmental impact factor level separately and then aggregates them by calculating the Environmental Impact Score (EIS. The proposed method uses environmental monitoring data and documented evidence instead of using simulation models. The proposed method has been applied to the 4 coal-fired power plants that have been operation in Turkey. The Environmental Impact Score was obtained for each power plant and their environmental performances were compared. It is expected that those environmental impact assessments will contribute to the decision-making process for environmental investments to those plants. The main advantage of the proposed method is its flexibility and ease of use.

Environmental impact assessment of coal power plants in operation

Science.gov (United States)

Bartan, Ayfer; Kucukali, Serhat; Ar, Irfan

2017-11-01

Coal power plants constitute an important component of the energy mix in many countries. However, coal power plants can cause several environmental risks such as: climate change and biodiversity loss. In this study, a tool has been proposed to calculate the environmental impact of a coal-fired thermal power plant in operation by using multi-criteria scoring and fuzzy logic method. We take into account the following environmental parameters in our tool: CO, SO2, NOx, particulate matter, fly ash, bottom ash, the cooling water intake impact on aquatic biota, and the thermal pollution. In the proposed tool, the boundaries of the fuzzy logic membership functions were established taking into account the threshold values of the environmental parameters which were defined in the environmental legislation. Scoring of these environmental parameters were done with the statistical analysis of the environmental monitoring data of the power plant and by using the documented evidences that were obtained during the site visits. The proposed method estimates each environmental impact factor level separately and then aggregates them by calculating the Environmental Impact Score (EIS). The proposed method uses environmental monitoring data and documented evidence instead of using simulation models. The proposed method has been applied to the 4 coal-fired power plants that have been operation in Turkey. The Environmental Impact Score was obtained for each power plant and their environmental performances were compared. It is expected that those environmental impact assessments will contribute to the decision-making process for environmental investments to those plants. The main advantage of the proposed method is its flexibility and ease of use.

Operational characteristics of nuclear power plants - modelling of operational safety

International Nuclear Information System (INIS)

Studovic, M.

1984-01-01

By operational experience of nuclear power plants and realize dlevel of availability of plant, systems and componenst reliabiliuty, operational safety and public protection, as a source on nature of distrurbances in power plant systems and lessons drawn by the TMI-2, in th epaper are discussed: examination of design safety for ultimate ensuring of safe operational conditions of the nuclear power plant; significance of the adequate action for keeping proess parameters in prescribed limits and reactor cooling rquirements; developed systems for measurements detection and monitoring all critical parameters in the nuclear steam supply system; contents of theoretical investigation and mathematical modeling of the physical phenomena and process in nuclear power plant system and components as software, supporting for ensuring of operational safety and new access in staff education process; program and progress of the investigation of some physical phenomena and mathematical modeling of nuclear plant transients, prepared at faculty of mechanical Engineering in Belgrade. (author)

Plant designer's view of the operator's role in nuclear plant safety

International Nuclear Information System (INIS)

Corcoran, W.R.; Church, J.F.; Cross, M.T.; Porter, N.J.

1981-01-01

The nuclear plant operator's role supports the design assumptions and equipment with four functional tasks. He must set up th plant for predictable response to disturbances, operate the plant so as to minimize the likelihood and severity of event initiators, assist in accomplishing the safety functions, and feed back operating experiences to reinforce or redefine the safety analyses' assumptions. The latter role enhances the operator effectiveness in the former three roles. The Safety Level Concept offers a different perspective that enables the operator to view his roles in nuclear plant safety. This paper outlines the operator's role in nuclear safety and classifies his tasks using the Safety Level Concept

Safety Culture in Pre-operational Phases of Nuclear Power Plant Projects

Energy Technology Data Exchange (ETDEWEB)

NONE

2012-09-15

An abundance of information exists on safety culture related to the operational phases of nuclear power plants; however, pre-operational phases present unique challenges. This publication focuses on safety culture during pre-operational phases that span the interval from before a decision to launch a nuclear power programme to first fuel load. It provides safety culture insights and focuses on eight generic issues: safety culture understanding; multicultural aspects; leadership; competencies and resource competition; management systems; learning and feedback; cultural assessments; and communication. Each issue is discussed in terms of: specific challenges; desired state; approaches and methods; and examples and resources. This publication will be of interest to newcomers and experienced individuals faced with the opportunities and challenges inherent in safety culture programmes aimed at pre-operational activities.

Safety Culture in Pre-operational Phases of Nuclear Power Plant Projects

International Nuclear Information System (INIS)

2012-01-01

An abundance of information exists on safety culture related to the operational phases of nuclear power plants; however, pre-operational phases present unique challenges. This publication focuses on safety culture during pre-operational phases that span the interval from before a decision to launch a nuclear power programme to first fuel load. It provides safety culture insights and focuses on eight generic issues: safety culture understanding; multicultural aspects; leadership; competencies and resource competition; management systems; learning and feedback; cultural assessments; and communication. Each issue is discussed in terms of: specific challenges; desired state; approaches and methods; and examples and resources. This publication will be of interest to newcomers and experienced individuals faced with the opportunities and challenges inherent in safety culture programmes aimed at pre-operational activities.

Intelligent operation system for nuclear power plants

International Nuclear Information System (INIS)

Morioka, Toshihiko; Fukumoto, Akira; Suto, Osamu; Naito, Norio.

1987-01-01

Nuclear power plants consist of many systems and are operated by skillful operators with plenty of knowledge and experience of nuclear plants. Recently, plant automation or computerized operator support systems have come to be utilized, but the synthetic judgment of plant operation and management remains as human roles. Toshiba is of the opinion that the activities (planning, operation and maintenance) should be integrated, and man-machine interface should be human-friendly. We have begun to develop the intelligent operation system aiming at reducing the operator's role within the fundamental judgment through the use of artificial intelligence. (author)

The operation of nuclear power plants

International Nuclear Information System (INIS)

Brosche, D.

1992-01-01

The duties to be performed in managing the operation of a nuclear power plant are highly diverse, as will be explained in this contribution by the examples of the Grafenrheinfeld Nuclear Power Station. The excellent safety record and the high availabilities of German nuclear power plants demonstrate that their operators have adopted the right approaches. Systematic evaluation of the operating experience accumulated inhouse and in other plants is of great significance in removing weak spots and improving operation. The manifold and complex activities in the structure of organization and of activities in a nuclear power plant require a high degree of division of labor. (orig.) [de

Science-based HRA: experimental comparison of operator performance to IDAC (Information-Decision-Action Crew) simulations

Energy Technology Data Exchange (ETDEWEB)

Shirley, Rachel [The Ohio State Univ., Columbus, OH (United States); Smidts, Carol [The Ohio State Univ., Columbus, OH (United States); Boring, Ronald [Idaho National Lab. (INL), Idaho Falls, ID (United States); Li, Yuandan [Univ. of Maryland, College Park, MD (United States); Mosleh, Ali [Univ. of Maryland, College Park, MD (United States)

2015-02-01

Information-Decision-Action Crew (IDAC) operator model simulations of a Steam Generator Tube Rupture are compared to student operator performance in studies conducted in the Ohio State University’s Nuclear Power Plant Simulator Facility. This study is presented as a prototype for conducting simulator studies to validate key aspects of Human Reliability Analysis (HRA) methods. Seven student operator crews are compared to simulation results for crews designed to demonstrate three different decision-making strategies. The IDAC model used in the simulations is modified slightly to capture novice behavior rather that expert operators. Operator actions and scenario pacing are compared. A preliminary review of available performance shaping factors (PSFs) is presented. After the scenario in the NPP Simulator Facility, student operators review a video of the scenario and evaluate six PSFs at pre-determined points in the scenario. This provides a dynamic record of the PSFs experienced by the OSU student operators. In this preliminary analysis, Time Constraint Load (TCL) calculated in the IDAC simulations is compared to TCL reported by student operators. We identify potential modifications to the IDAC model to develop an “IDAC Student Operator Model.” This analysis provides insights into how similar experiments could be conducted using expert operators to improve the fidelity of IDAC simulations.

Remote Sensing and Modeling for Improving Operational Aquatic Plant Management

Science.gov (United States)

Bubenheim, Dave

2016-01-01

The California Sacramento-San Joaquin River Delta is the hub for California’s water supply, conveying water from Northern to Southern California agriculture and communities while supporting important ecosystem services, agriculture, and communities in the Delta. Changes in climate, long-term drought, water quality changes, and expansion of invasive aquatic plants threatens ecosystems, impedes ecosystem restoration, and is economically, environmentally, and sociologically detrimental to the San Francisco Bay/California Delta complex. NASA Ames Research Center and the USDA-ARS partnered with the State of California and local governments to develop science-based, adaptive-management strategies for the Sacramento-San Joaquin Delta. The project combines science, operations, and economics related to integrated management scenarios for aquatic weeds to help land and waterway managers make science-informed decisions regarding management and outcomes. The team provides a comprehensive understanding of agricultural and urban land use in the Delta and the major water sheds (San Joaquin/Sacramento) supplying the Delta and interaction with drought and climate impacts on the environment, water quality, and weed growth. The team recommends conservation and modified land-use practices and aids local Delta stakeholders in developing management strategies. New remote sensing tools have been developed to enhance ability to assess conditions, inform decision support tools, and monitor management practices. Science gaps in understanding how native and invasive plants respond to altered environmental conditions are being filled and provide critical biological response parameters for Delta-SWAT simulation modeling. Operational agencies such as the California Department of Boating and Waterways provide testing and act as initial adopter of decision support tools. Methods developed by the project can become routine land and water management tools in complex river delta systems.

Operating the plant, quality assurance, and the job of the operating staff, Volume Twelve

International Nuclear Information System (INIS)

Anon.

1986-01-01

Subject matter includes operating the plant (the role of the operator, the control room, plant technical specifications, plant operating procedures, initial startup program, BWR/PWR plant startup, BWR/PWR steady state power operation, BWR/PWR transient operation, emergency operation), quality assurance (what is quality, what is quality control, quality assurance includes quality control, government regulation and quality assurance, administrative controls for nuclear power plants, the necessity of reviews and audits, practical quality assurance), and the job of the operating staff (the plant operating staff, plant safety, first aid and resuscitation, general plant hazards, personnel protective equipment, handling chemicals, handling compressed gas, equipment repair and maintenance, communicating with others

Representing Operational Knowledge of PWR Plant by Using Multilevel Flow Modelling

DEFF Research Database (Denmark)

Zhang, Xinxin; Lind, Morten; Jørgensen, Sten Bay

2014-01-01

situation and support operational decisions. This paper will provide a general MFM model of the primary side in a standard Westinghouse Pressurized Water Reactor ( PWR ) system including sub - systems of Reactor Coolant System, Rod Control System, Chemical and Volume Control System, emergency heat removal......The aim of this paper is to explore the capability of representing operational knowledge by using Multilevel Flow Modelling ( MFM ) methodology. The paper demonstrate s how the operational knowledge can be inserted into the MFM models and be used to evaluate the plant state, identify the current...... systems. And the sub - systems’ functions will be decomposed into sub - models according to different operational situations. An operational model will be developed based on the operating procedure by using MFM symbols and this model can be used to implement coordination rules for organize the utilizati...

Thermal power plant design and operation

CERN Document Server

Sarkar, Dipak

2015-01-01

Thermal Power Plant: Design and Operation deals with various aspects of a thermal power plant, providing a new dimension to the subject, with focus on operating practices and troubleshooting, as well as technology and design. Its author has a 40-long association with thermal power plants in design as well as field engineering, sharing his experience with professional engineers under various training capacities, such as training programs for graduate engineers and operating personnel. Thermal Power Plant presents practical content on coal-, gas-, oil-, peat- and biomass-fueled thermal power

Classification of nuclear power plant operator support systems

International Nuclear Information System (INIS)

Alpeev, A.S.

1994-01-01

The objective of this survey was to examine the general characteristics of modern nuclear power plant process monitoring/control systems and to apply developing technology (intellectual automation) in order to improve the man-machine interface. The support systems that implement each phase of the control function...information, assessment, decision-making, and implementation...were discussed, and where applicable, intellectual automation was applied to the support system. It was concluded that the application of intellectual automation, as well as other (undefined) possibilities for improving the man-machine interface, would relieve the operator of many routine activities and allow him to readily apply high potential to those poorly-formalized scenarios in which the operator's work can't be automated. It was also concluded that the development of such support systems would not be without problems, i.e. software certification, traning, and jurisdictional questions

The experiences from implementing decision support technology to address water management plans in an operational environment

Energy Technology Data Exchange (ETDEWEB)

McArdle, S. [4DM Inc., Toronto, ON (Canada); Tonkin, C. [Ontario Power Generation Inc., Toronto, ON (Canada)

2005-07-01

This presentation described Ontario Power Generation's experience in implementing a decision support tool to enable water management plans for its operations through technology solutions. All hydroelectric producers in Ontario are required to make water management plans in order to maintain water levels and flows in their operating regions. This regulation was created in response to environmental concerns as well as to changes in the electricity market and growth of residential and cottage property near water bodies. In order to keep informed and to address compliance issues, operators and managers need situation awareness information to balance operational decisions. The online Adaptive Water Management System (AWMS) decision support tool was recently adopted by Ontario Power Generation to provide information needed to address the requirements of Water Management Plans. The AWMS provides users with information on water levels and flows; the ability to implement, modify, and manage daily instructions at the facilities; track conditions in the watershed; and, provide a status of compliance. The tool was developed by 4DM Inc. in collaboration with Ottawa St. Lawrence Plant Group for the Madawaska River Watershed Management, a model partnership between operator, regulator and Public Advisory Committee to develop a water management plan.

Probabilistic Risk Assessment for Decision Making During Spacecraft Operations

Science.gov (United States)

Meshkat, Leila

2009-01-01

Decisions made during the operational phase of a space mission often have significant and immediate consequences. Without the explicit consideration of the risks involved and their representation in a solid model, it is very likely that these risks are not considered systematically in trade studies. Wrong decisions during the operational phase of a space mission can lead to immediate system failure whereas correct decisions can help recover the system even from faulty conditions. A problem of special interest is the determination of the system fault protection strategies upon the occurrence of faults within the system. Decisions regarding the fault protection strategy also heavily rely on a correct understanding of the state of the system and an integrated risk model that represents the various possible scenarios and their respective likelihoods. Probabilistic Risk Assessment (PRA) modeling is applicable to the full lifecycle of a space mission project, from concept development to preliminary design, detailed design, development and operations. The benefits and utilities of the model, however, depend on the phase of the mission for which it is used. This is because of the difference in the key strategic decisions that support each mission phase. The focus of this paper is on describing the particular methods used for PRA modeling during the operational phase of a spacecraft by gleaning insight from recently conducted case studies on two operational Mars orbiters. During operations, the key decisions relate to the commands sent to the spacecraft for any kind of diagnostics, anomaly resolution, trajectory changes, or planning. Often, faults and failures occur in the parts of the spacecraft but are contained or mitigated before they can cause serious damage. The failure behavior of the system during operations provides valuable data for updating and adjusting the related PRA models that are built primarily based on historical failure data. The PRA models, in turn

Development of an investment decision tool for aged nuclear power plants under uncertainty

International Nuclear Information System (INIS)

Takashima, Ryuta; Nagano, Koji

2010-01-01

The nuclear power generating stock in Japan, which provides 30% or more of the nationwide electricity supply in recent years, is heading into the era of plant aging as those units over 40 years of operation emerge in 2010 and onward. Under accumulating uncertainties surrounding investment decisions, one of the key questions is how best to manage the existing capacity by choosing a wisest option among dismantling, refurbishment, and replacement. This report attempts to develop a methodology to analyze investment decision on aged nuclear units based on real-option analysis, and then presents illustrative simulation runs to demonstrate functions of the numerical models. Major findings are summarized as follows: a) When compared with the conventional net present value (NPV) method, the proposed model is capable to deal with uncertainty explicitly by taking volatility in the formula. Also, for the replacement option, one can choose optimal timings of the dismantling the new plant independently. b) As the profitability increases, the model suggests different investment option as optimal, starting from dismantling to replacement, further to refurbishment, and again to replacement as the most basic pattern. Additionally, where two of the strategies have similar values, postponement of both decisions can be optimal. Through these exercises, the proposed methodology proved itself capable for raising valuable implications to investment decisions in managing the production fleet. (author)

Training of power plant operating personnel

International Nuclear Information System (INIS)

Kraftwerksschule, E.V.

1986-01-01

In Germany, professional training of power plant operating personnel became an important issue in the fifties, when power plant parameters as well as complexity of instrumentation and control increased considerably. Working Groups of VGB Technische Vereiningung der Grosskraftwerketreiber e.v. (Association of Large Power Plant Operators) developed a professional career for power plant operating personnel and defined pre-requisites, scope and objectives of training. In 1957 the German utilities founded KRAFTWERKSSCHULE E.V. (kws) as a school for theoretical training and for guidance of practical training in the power plants. KWS is a non-profit organisation and independent of authorities. Today KWS has 127 members in Germany and in 6 other countries. The objectives of KWS include the training of: -Kraftwerker (control room operators; - Kraftwerksmesiter (shift supervisors); and - shift engineers; according the guidelines of the VGB

Fatigue assessments in operating nuclear power plants

International Nuclear Information System (INIS)

Gosselin, S.R.; Deardorff, A.F.; Peltola, D.W.

1994-01-01

In November 1991, the ASME Section XI Task Group on Operating Plant Fatigue Assessment was formed to develop criteria and evaluation methodology for evaluating the effects of cyclic operation in operating nuclear power plants. The objective was to develop guidelines for inclusion in Section XI that could be used by plant operators in evaluating fatigue concerns and their impact on serviceability. This paper discusses the work performed by the Task Group. It explores the concept of ''Fatigue Design Basis'' versus ''Fatigue Operating Basis'' by examining the roles of ASME Section III and ASME Section XI in the design and operation of the nuclear power plants. Guidelines are summarized that may help plant operators perform effective design transient cycle evaluations and optimize cycle counting and fatigue usage tracking. The alternative fatigue evaluation approach using flaw tolerance is also introduced

A decision theoretic approach to an accident sequence: when feedwater and auxiliary feedwater fail in a nuclear power plant

International Nuclear Information System (INIS)

Svenson, Ola

1998-01-01

This study applies a decision theoretic perspective on a severe accident management sequence in a processing industry. The sequence contains loss of feedwater and auxiliary feedwater in a boiling water nuclear reactor (BWR), which necessitates manual depressurization of the reactor pressure vessel to enable low pressure cooling of the core. The sequence is fast and is a major contributor to core damage in probabilistic risk analyses (PRAs) of this kind of plant. The management of the sequence also includes important, difficult and fast human decision making. The decision theoretic perspective, which is applied to a Swedish ABB-type reactor, stresses the roles played by uncertainties about plant state, consequences of different actions and goals during the management of a severe accident sequence. Based on a theoretical analysis and empirical simulator data the human error probabilities in the PRA for the plant are considered to be too small. Recommendations for how to improve safety are given and they include full automation of the sequence, improved operator training, and/or actions to assist the operators' decision making through reduction of uncertainties, for example, concerning water/steam level for sufficient cooling, time remaining before insufficient cooling level in the tank is reached and organizational cost-benefit evaluations of the events following a false alarm depressurization as well as the events following a successful depressurization at different points in time. Finally, it is pointed out that the approach exemplified in this study is applicable to any accident scenario which includes difficult human decision making with conflicting goals, uncertain information and with very serious consequences

Investigations for decision making on an old tailing pond of a former experimental metallurgical plant

International Nuclear Information System (INIS)

Razikov, Z.A.; Pavljuk, L.M.; Bezzubov, N.I.

2002-01-01

Investigations are described on an abandoned tailing pond of a former experimental metallurgical plant which operated during the period 1945-1950. The aim of these investigations was to explore radiological hazards arising from the tailing pond for the population and to obtain data for decision making on redeployment or dumping of the pond. Methods used, results obtained and conclusions drawn are outlined. (author)

Pricing, Variety, and Inventory Decisions in Retail Operations Management

OpenAIRE

Maddah, Bacel

2005-01-01

This dissertation is concerned with decision making in retail operations management. Specifically, we focus on pricing, variety, and inventory decisions, which are at the interface of the marketing and operations functions of a retail firm. We consider two problems that relate to two major types of retail goods. First, we study joint pricing, variety, and inventory decisions for a set of substitutable" items that serve the same need for the consumer (commonly referred to as a "retailer's ...

Plant life extensions for German nuclear power plants? Controversial discussion profit taking of nuclear power plant operators; Laufzeitverlaengerungen fuer die deutschen Kernkaftwerke? Kurzanalyse zu den Gewinnmitnahmen der KKW-Betreiber

Energy Technology Data Exchange (ETDEWEB)

Matthes, Felix C.

2009-10-15

The discussion on the plant life extensions for German nuclear power plants beyond the residual quantity of electricity particularly focus on three aspects: Effects for the emission of carbon dioxide as a greenhouse gas; Development of the electricity price for which a reduction or attenuation is postulated due to a plant life extension; Skimming of additional profits at operating companies and their use in the safeguarding of the future (development of renewable energies, support of energy efficiency, promotion of the research, consolidation of the public budget, and so on). Under this aspect, the author of the contribution under consideration reports on the profit taking of nuclear power plant operators. The presented analysis considers three aspects: (a) Specification of the quantity structures for the investigated model of plant life extension; (b) The decisive parameter is the revenue situation and thus the price development for electricity at wholesale markets; (c) Determination and evaluation of the course in time of the profit taking.

Utility systems operation: Optimisation-based decision making

International Nuclear Information System (INIS)

Velasco-Garcia, Patricia; Varbanov, Petar Sabev; Arellano-Garcia, Harvey; Wozny, Guenter

2011-01-01

Utility systems provide heat and power to industrial sites. The importance of operating these systems in an optimal way has increased significantly due to the unstable and in the long term rising prices of fossil fuels as well as the need for reducing the greenhouse gas emissions. This paper presents an analysis of the problem for supporting operator decision making under conditions of variable steam demands from the production processes on an industrial site. An optimisation model has been developed, where besides for running the utility system, also the costs associated with starting-up the operating units have been modelled. The illustrative case study shows that accounting for the shut-downs and start-ups of utility operating units can bring significant cost savings. - Highlights: → Optimisation methodology for decision making on running utility systems. → Accounting for varying steam demands. → Optimal operating specifications when a demand change occurs. → Operating costs include start-up costs of boilers and other units. → Validated on a real-life case study. Up to 20% cost savings are possible.

Fair play in energy policy decisions: Procedural fairness, outcome fairness and acceptance of the decision to rebuild nuclear power plants

International Nuclear Information System (INIS)

Visschers, Vivianne H.M.; Siegrist, Michael

2012-01-01

To raise public acceptance of new energy policies, promoting the fairness of the outcomes and of the decision-making procedure has been suggested. Very few studies have examined the role of fairness in public acceptance of rebuilding nuclear power plants. Therefore, using a large mail survey, we investigated the public’s acceptance of the decision to rebuild nuclear power plants in Switzerland by 2020. The study examined the influence of procedural fairness and outcome fairness on the acceptance of this decision, as well as other factors such as risk perception and benefit perception. Additionally, we investigated the moderating influence of general attitudes towards nuclear power on the relation between fairness and decision acceptance. Results indicated that outcome fairness strongly increased decision acceptance, along with general attitudes towards nuclear power and perceived economic benefits. Procedural fairness had only a small impact on decision acceptance. The influence of fairness on decision acceptance did not seem to depend on general nuclear attitudes. Our findings imply that, in the case of rebuilding nuclear power plants, perceived benefits and outcome fairness are important determinants of acceptance of the decision, while procedural fairness only has a limited impact. - Highlights: ► We investigated the role of fairness in the acceptance of a nuclear policy decision. ► Outcome fairness strongly influenced decision acceptance regarding nuclear power plants. ► The role of procedural fairness was relatively small in this respect. ► Also, nuclear attitudes and perceived economic benefits affected decision acceptance. ► Outcome fairness seems more relevant for decision acceptance than procedural fairness.

Development of JOYO Plant Operation Management Expert Tool (JOYPET)

International Nuclear Information System (INIS)

Michino, Masanobu; Terano, Toshihiro; Hanawa, Mikio; Aoki, Hiroshi; Okubo, Toshiyuki

2000-03-01

The Operation and Maintenance Support Systems for JOYO are being developed, with the aim of ensuring the stable and safe operation of JOYO and improving operational reliability of future FBR plants. Plant Operation Management Expert Tool named JOYPET had been developed as one of the Operation and Maintenance Support Systems, which helps plant operation management. The following functions were developed and applied. (1) Papers management (Plant status management) function for maintenance activities, (2) Isolation management support function for plant operation, (3) Automatically drawing function of plant operation schedule, (4) Isolation judgment function for plant operation. By use this system, the plant management of JOYO was able to improved reliability and reduced manpower. (author)

China’s Nuclear Power Plants in Operation

Institute of Scientific and Technical Information of China (English)

无

2011-01-01

Qinshan Plant Phase I Located in Haiyan,Zhejiang Province,Qinshan Nuclear Power Plant Phase I is t he first 300-megawatt pressurized water reactor (PWR) nuclear power plant independently designed,constructed,operated and managed by China.The plant came into commercial operation in April 1994.

Modifications at operating nuclear power plants

International Nuclear Information System (INIS)

Duffy, T.J.; Gazda, P.A.

1985-01-01

Modifications at operating nuclear power plants offer the structural engineer many challenges in the areas of scheduling of work, field adjustments, and engineering staff planning. The scheduling of structural modification work for operating nuclear power plants is normally closely tied to planned or unplanned outages of the plant. Coordination between the structural engineering effort, the operating plant staff, and the contractor who will be performing the modifications is essential to ensure that all work can be completed within the allotted time. Due to the inaccessibility of some areas in operating nuclear power plants or the short time available to perform the structural engineering in the case of an unscheduled outrage, field verification of a design is not always possible prior to initiating the construction of the modification. This requires the structural engineer to work closely with the contractor to promptly resolve problems due to unanticipated interferences or material procurement problems that may arise during the course of construction. The engineering staff planning for structural modifications at an operating nuclear power plant must be flexible enough to permit rapid response to the common ''fire drills,'' but controlled enough to ensure technically correct designs and to minimize the expenditure of man-hours and the resulting engineering cost

Knowledge base for power plant operation and its application to operation guide

International Nuclear Information System (INIS)

Doi, Atsushi; Sakaguchi, Toshiaki

1986-01-01

The present study is aimed at constructing a knowledge base for supervisory control operation in power plants and developing an operation guidance by using it. Examination is made to provide dignosis procedures on the basis of an existing alarm system. An operation guidance procedure for diagnosis is proposed which is to be followed when several alarms are sounded simultaneously in a power plant, and application of the procedure to an existing plant is examined. The operation manual for the plant includes 75 description items for six alarms. It is shown that the number of items related to these alarms can be reduced by 70 % by rearranging them according to the procedure. Another investigation is conducted to provide an operation manual for diagnosis to be used when one alarm is sounded in a plant. The quality of the manual developed is on nearly the same level with that for the existing plant examined. When a knowledge base is to be constructed from an existing operation manual, the processing operation generally requires a certain level of linguistic comprehension ability, such as for judgment of synonyms. It is demonstrated that the procedure proposed here is able to develop a high-quality knowledge base with standardized terminology. The procedure can also serve to construct operation manuals for plants in other industrial fields. (Nogami, K.)

The role of human performance in safe operation of complex plants

International Nuclear Information System (INIS)

Preda, Irina Aida; Lazar, Roxana Elena; Croitoru, Cornelia

1999-01-01

According to statistics, about 20-30% from the failures occurring in plants are caused directly or indirectly by human errors. Furthermore, it was established that 10-15 percents of the global failures are related to the human errors. These are mainly due to the wrong actions, maintenance errors, and misinterpretation of instruments. The human performance is influenced by: professional ability, complexity and danger of the plant, experience in the same working place, level of skills, events in personal and/or professional life, discipline, social ambience and somatic health. The human performances assessment in the probabilistic safety assessment offers the possibility of evaluation for human contribution to the events sequences outcome. A human error may be recovered before the unwanted consequences had been occurred on system. This paper presents the possibilities to use the probabilistic methods (event tree, fault tree) to identify the solution for human reliability improvement in order to minimise the risk in industrial plant operation. Also, are defined the human error types and their causes and the 'decision tree method' is presented as technique in our analyses for human reliability assessment. The exemplification of human error analysis method was achieved based on operation data for Valcea heavy water pilot plant. (authors)

Regulatory decision making by decision analyses

International Nuclear Information System (INIS)

Holmberg, J.; Pulkkinen, U.

1993-11-01

The Technical Research Centre of Finland (VTT) has studied with the Finnish Centre for Radiation and Nuclear Safety (STUK) the applicability of decision analytic approach to the treatment of nuclear safety related problems at the regulatory body. The role of probabilistic safety assessment (PSA) in decision making has also been discussed. In the study, inspectors from STUK exercised with a decision analytic approach by reoperationalizing two occurred and solved problems. The research scientist from VTT acted as systems analysts guiding the analysis process. The first case was related to a common cause failure phenomenon in solenoid valves controlling pneumatic valves important to safety of the plant. The problem of the regulatory body was to judge whether to allow continued operation or to require more detailed inspections and in which time chedule the inspections should be done. The latter problem was to evaluate design changes of external electrical grid connections after a fire incident had revealed weakness in the separation of electrical system. In both cases, the decision analysis was carried out several sessions in which decision makers, technical experts as well as experts of decision analysis participated. A multi-attribute value function was applied as a decision model so that attributes had to be defined to quantify the levels of achievements of the objectives. The attributes included both indicators related to the level of operational safety of the plant such as core damage frequency given by PSA, and indicators related to the safety culture, i.e., how well the chosen option fits on the regulatory policy. (24 refs., 6 figs., 9 tabs.)

Plant life management. An integral part of operation and maintenance policy

International Nuclear Information System (INIS)

Faidy, C.; Hutin, J.-P.

2002-01-01

Electricite de France is now operating 58 PWR nuclear power plants that produce 75% of electricity in France. Besides maintaining safety and availability on a routine basis, it is outmost important to protect the investment. That is the reason why EDF is devoting important resources to implement ageing management concern as an integral part of operation and maintenance programs (for example through appropriate data collection and analysis, specific repair and replacement projects and important anticipation efforts, taking in account the high level of standardisation of the units). A particular organisation has been set up to continuously observe and analyse all activities so as to make sure that ageing concern is correctly taken in account in strategies and that no decisions are susceptible to impair plant lifetime. This 'lifetime program' is paying attention to technical issues associated with main components but is also dealing with issues related to economics and industry situation. (orig.)

Operator decision support system for sodium loop

Energy Technology Data Exchange (ETDEWEB)

Lee, Kwang Hyeang; Park, Kyu Ho; Kim, Tak Kon; Jo, Choong Ho; Seong, Kyeong A; Lee, Keon Myeong; Kim, Yeong Dal; Kim, Chang Beom; Kim, Jong Kyu; Jo, Hee Chang; Lee, Ji Hyeong; Jeong, Yoon Soo; Chio, Jong Hyeong; Jeong, Bong Joon; Hong, Joon Seong; Kim, Bong Wan; Seong, Byeong Hak [Korea Advanced Institute Science and Technology, Taejon (Korea, Republic of)

1994-07-01

The objective of this study is to develop an operator decision support system by computerizing the sodium circuit. This study developed graphical display interface for the control panel which provides the safety control of equipment, the recognition of experimental process states and sodium circuit states. In this study, basic work to develop an operator decision support real-time expert system for sodium loop was carried out. Simplification of control commands and effective operation of various real-time data and signals by equipment code standardization are studied. The cost ineffectiveness of the single processor structure provides the ground for the development of cost effective parallel processing system. The important tasks of this study are (1) design and implementation of control state surveillance panel of sodium loop, (2) requirement analysis of operator support real-time expert system for sodium loop, (3) design of standard code rule for operating equipment and research on the cost effective all purpose parallel processing system and (4) requirement analysis of expert system and design of control state variables and user interface for experimental process. 10 refs., 36 figs., 20 tabs.

Cognitive decision errors and organization vulnerabilities in nuclear power plant safety management: Modeling using the TOGA meta-theory framework

International Nuclear Information System (INIS)

Cappelli, M.; Gadomski, A. M.; Sepiellis, M.; Wronikowska, M. W.

2012-01-01

In the field of nuclear power plant (NPP) safety modeling, the perception of the role of socio-cognitive engineering (SCE) is continuously increasing. Today, the focus is especially on the identification of human and organization decisional errors caused by operators and managers under high-risk conditions, as evident by analyzing reports on nuclear incidents occurred in the past. At present, the engineering and social safety requirements need to enlarge their domain of interest in such a way to include all possible losses generating events that could be the consequences of an abnormal state of a NPP. Socio-cognitive modeling of Integrated Nuclear Safety Management (INSM) using the TOGA meta-theory has been discussed during the ICCAP 2011 Conference. In this paper, more detailed aspects of the cognitive decision-making and its possible human errors and organizational vulnerability are presented. The formal TOGA-based network model for cognitive decision-making enables to indicate and analyze nodes and arcs in which plant operators and managers errors may appear. The TOGA's multi-level IPK (Information, Preferences, Knowledge) model of abstract intelligent agents (AIAs) is applied. In the NPP context, super-safety approach is also discussed, by taking under consideration unexpected events and managing them from a systemic perspective. As the nature of human errors depends on the specific properties of the decision-maker and the decisional context of operation, a classification of decision-making using IPK is suggested. Several types of initial situations of decision-making useful for the diagnosis of NPP operators and managers errors are considered. The developed models can be used as a basis for applications to NPP educational or engineering simulators to be used for training the NPP executive staff. (authors)

Cognitive decision errors and organization vulnerabilities in nuclear power plant safety management: Modeling using the TOGA meta-theory framework

Energy Technology Data Exchange (ETDEWEB)

Cappelli, M. [UTFISST, ENEA Casaccia, via Anguillarese 301, Rome (Italy); Gadomski, A. M. [ECONA, Centro Interuniversitario Elaborazione Cognitiva Sistemi Naturali e Artificiali, via dei Marsi 47, Rome (Italy); Sepiellis, M. [UTFISST, ENEA Casaccia, via Anguillarese 301, Rome (Italy); Wronikowska, M. W. [UTFISST, ENEA Casaccia, via Anguillarese 301, Rome (Italy); Poznan School of Social Sciences (Poland)

2012-07-01

In the field of nuclear power plant (NPP) safety modeling, the perception of the role of socio-cognitive engineering (SCE) is continuously increasing. Today, the focus is especially on the identification of human and organization decisional errors caused by operators and managers under high-risk conditions, as evident by analyzing reports on nuclear incidents occurred in the past. At present, the engineering and social safety requirements need to enlarge their domain of interest in such a way to include all possible losses generating events that could be the consequences of an abnormal state of a NPP. Socio-cognitive modeling of Integrated Nuclear Safety Management (INSM) using the TOGA meta-theory has been discussed during the ICCAP 2011 Conference. In this paper, more detailed aspects of the cognitive decision-making and its possible human errors and organizational vulnerability are presented. The formal TOGA-based network model for cognitive decision-making enables to indicate and analyze nodes and arcs in which plant operators and managers errors may appear. The TOGA's multi-level IPK (Information, Preferences, Knowledge) model of abstract intelligent agents (AIAs) is applied. In the NPP context, super-safety approach is also discussed, by taking under consideration unexpected events and managing them from a systemic perspective. As the nature of human errors depends on the specific properties of the decision-maker and the decisional context of operation, a classification of decision-making using IPK is suggested. Several types of initial situations of decision-making useful for the diagnosis of NPP operators and managers errors are considered. The developed models can be used as a basis for applications to NPP educational or engineering simulators to be used for training the NPP executive staff. (authors)

Regulatory framework for nuclear power plant operation

International Nuclear Information System (INIS)

Perez Alcaniz, T.; Esteban Barriendos, M.

1995-01-01

As the framework of standards and requirements covering each phase of nuclear power plant project and operation developed, plant owners defined their licensing commitments (codes, rules and design requirements) during the project and construction phase before start-up and incorporated regulatory requirements imposed by the regulatory Body during the licensing process prior to operation. This produces a regulatory framework for operating a plant. It includes the Licensing Basis, which is the starting point for analyzing and incorporating new requirements, and for re-evaluation of existing ones. This presentation focuses on the problems of applying this regulatory framework to new operating activities, in particular to new projects, analyzing new requirements, and reconsidering existing ones. Clearly establishing a plant's licensing basis allows all organizations involved in plant operation to apply the requirements in a more rational way. (Author)

Plant lifetime reliability and risk: Addressing today's strategies for making tomorrow's decisions

International Nuclear Information System (INIS)

Boccio, J.L.

1986-01-01

This paper presents an overview of some of the research projects, conducted for the US Nuclear Regulatory Commission (NRC) that deal with the question: How can an acceptable level of risk of a nuclear power plant be maintained throughout its design life? With a viewpoint that life extension planning for a plant can be viewed as a long-range, strategic maintenance program, the products of this research are discussed from the perspective of being elements that can tie day-to-day, plant operational tactical decisions on component/system reliability with long-range strategic maintenance goals. A common factor in addressing issues associated with design life and life extension is the issue of component aging and the reliability implications of aging. A time-dependent reliability model is described which contains some of the requisite ingredients and is built on a framework from which the component aging/component reliability issue can be addressed. By way of select examples, the additional work needed to further address plant lifetime reliability and risk is indicated

Improving operator quality at Genkai Nuclear Power Plant

International Nuclear Information System (INIS)

Kuwano, Takeshi.

1989-01-01

Improvement in operator quality, or improvement in an operator's skill and professional knowledge, is of prime importance because of its great influence on safe and steady plant operation. This paper describes the education and training of reactor operators at the Genkai pressurized water reactor nuclear power plant with respect to the following topics: organization of Genkai power plant; education and training program management; training at the Nuclear Training Center; training and education on-site including emergency procedures training, normal operating procedures training, informational study of emergency conditions in existing plants, and all-around training of operators; qualifying tests for supervisors; and operator motivation

Development of a majority vote decision module for a self-diagnostic monitoring system for an air-operated valve system

Energy Technology Data Exchange (ETDEWEB)

Kim, Woo Shin [Dept. of Information and Communication Engineering, Sejong University, Seoul (Korea, Republic of); Chai, Jang Bom [Dept. of Mechanical Engineering, Ajou University, Suwon (Korea, Republic of); Kim, In Taek [Dept. of Information and Communication Engineering, Myongji University, Yongin (Korea, Republic of)

2015-08-15

A self-diagnostic monitoring system is a system that has the ability to measure various physical quantities such as temperature, pressure, or acceleration from sensors scattered over a mechanical system such as a power plant, in order to monitor its various states, and to make a decision about its health status. We have developed a self-diagnostic monitoring system for an air-operated valve system to be used in a nuclear power plant. In this study, we have tried to improve the self-diagnostic monitoring system to increase its reliability. We have implemented three different machine learning algorithms, i.e., logistic regression, an artificial neural network, and a support vector machine. After each algorithm performs the decision process independently, the decision-making module collects these individual decisions and makes a final decision using a majority vote scheme. With this, we performed some simulations and presented some of its results. The contribution of this study is that, by employing more robust and stable algorithms, each of the algorithms performs the recognition task more accurately. Moreover, by integrating these results and employing the majority vote scheme, we can make a definite decision, which makes the self-diagnostic monitoring system more reliable.

Development of a majority vote decision module for a self-diagnostic monitoring system for an air-operated valve system

International Nuclear Information System (INIS)

Kim, Woo Shin; Chai, Jang Bom; Kim, In Taek

2015-01-01

A self-diagnostic monitoring system is a system that has the ability to measure various physical quantities such as temperature, pressure, or acceleration from sensors scattered over a mechanical system such as a power plant, in order to monitor its various states, and to make a decision about its health status. We have developed a self-diagnostic monitoring system for an air-operated valve system to be used in a nuclear power plant. In this study, we have tried to improve the self-diagnostic monitoring system to increase its reliability. We have implemented three different machine learning algorithms, i.e., logistic regression, an artificial neural network, and a support vector machine. After each algorithm performs the decision process independently, the decision-making module collects these individual decisions and makes a final decision using a majority vote scheme. With this, we performed some simulations and presented some of its results. The contribution of this study is that, by employing more robust and stable algorithms, each of the algorithms performs the recognition task more accurately. Moreover, by integrating these results and employing the majority vote scheme, we can make a definite decision, which makes the self-diagnostic monitoring system more reliable

IDENTIFYING OPERATIONAL REQUIREMENTS TO SELECT SUITABLE DECISION MODELS FOR A PUBLIC SECTOR EPROCUREMENT DECISION SUPPORT SYSTEM

Directory of Open Access Journals (Sweden)

Mohamed Adil

2014-10-01

Full Text Available Public sector procurement should be a transparent and fair process. Strict legal requirements are enforced on public sector procurement to make it a standardised process. To make fair decisions on selecting suppliers, a practical method which adheres to legal requirements is important. The research that is the base for this paper aimed at identifying a suitable Multi-Criteria Decision Analysis (MCDA method for the specific legal and functional needs of the Maldivian Public Sector. To identify such operational requirements, a set of focus group interviews were conducted in the Maldives with public officials responsible for procurement decision making. Based on the operational requirements identified through focus groups, criteria-based evaluation is done on published MCDA methods to identify the suitable methods for e-procurement decision making. This paper describes the identification of the operational requirements and the results of the evaluation to select suitable decision models for the Maldivian context.

Industrial Fuel Gas Demonstration Plant Program. Demonstration plant operation plan (Deliverable No. 38)

Energy Technology Data Exchange (ETDEWEB)

None

1979-01-01

The Demo Plant Operating Plan is composed of the following sequence of events starting with the training or personnel, familiarizing of the personnel with the plant and completing the long-term run in the following sequences: inspection during construction, plant completion, shakedown of equipment, process unit startup, shakedown of process units, variable run operation and a turnaround. During the construction period, technical personnel from DRC, MLGW and IGT will be at the plant site becoming familiar with the equipment, its installation and all of the auxiliaries so that on completion of construction they will be well grounded on the plant detail and its configuration. At the same time the supervisory operating personnel will have hands on training the gasifier operation at the IGT pilot plant to develop a field for gasifier operation. As a plant sections are completed, they will be checked out in accordance with the contractor and operator (client) procedure as outlined. Subsequent to this, various vendor designs and furnished equipment will be checked out operating-wise and a performance test run if feasible. The actual startup of the plant will be subsequential with the support areas as utilities, coal handling and waste treatment being placed in operation first. Subsequent to this the process units will be placed in operation starting from the rear of the process train and working forward. Thus the downstream units will be operating before the reactor is run on coal. The reactor will be checked out on coke operation.

Review of decision aids for nuclear-plant operators

International Nuclear Information System (INIS)

Kisner, R.A.

1983-01-01

Responses to various computer-based operational aids varied widely in detail, thus forcing distillation of the salient features of many operational aids from information sources other than the initial questionnaire. These sources included technical and management presentations, technical papers and reports, personal discussions, taped responses, sales brochures, system specifications and schematics, and other documents. The data base is dynamic, not static, owing to the nature of current trends in operational aid development. The information contained in it is subject to review and revision by the developing organizations. More systems are pending review and entry into the data base; hence the list is incomplete

The role of risk analysis in control of complex plants' safety operation

International Nuclear Information System (INIS)

Dumitrescu, Maria; Preda, Irina Aida; Lazar, Roxana Elena; Carcadea, Elena

1999-01-01

The problem of risk estimation, assessment and control is necessary to be discussed at every decision level of an activity. In this way the performances of a system, action or technology are qualitatively assessed by indicating the possible consequences on environmental, people or property. The paper presents methodologies of risk assessment successfully applied on isotopic separation plants. The quantitative methodologies presented use fault tree and event tree to determine the accident states frequency and physical models to analyse the dispersion in atmosphere of dangerous substances. The qualitative methodologies use fuzzy models for the multi-criteria decision making, models based on risk matrix built on the basis of a combination between severity and probability of maximum admissible consequence. These methodologies present the following steps for applying: familiarising with the activity in study, establishing the adequate method of risk assessment, realising of the model of risk assessment for the activity or objective in study, developing of application of the proposed model. Applying this methodology to isotopic separation plants has led to: analysis of operation events and establishing of principal types of events potentially dangerous, analysis of human error in these plants operation and operating experience assessment, technical specifications optimisation by probabilistic safety assessment, reliability analysis and development of reliability and exploitation events database, post accident events analysis (releases, fires, explosions) and mathematical modelling of dispersion in atmosphere of dangerous substances. The risk concept being complex and with multiple implications, it is not the case of a rigid approaching neither of existence of some methods universally valid. Because of these reasons choosing of the most appropriate method for the risk assessment of an activity, leads to solution in due time, of some problems with economic, social

The role of risk analysis in control of complex plant safe operation

International Nuclear Information System (INIS)

Dumitrescu, Maria; Preda, Irina Aida; Lazar, Roxana Elena; Carcadea, Elena

1999-01-01

The problem of risk estimation assessment and control is necessary to be discussed in every decision making level of an activity. Performances of a system, action or technology, by indicating the possible consequences on environment, people or property should be qualitatively assessed. The paper presents methodologies of risk assessment successful applied on isotopic separation plants. The quantitative methodologies presented, use fault tree and event tree to determine the accident states frequency, physical models to analyse the dispersion in atmosphere of dangerous substances. The qualitative methodologies use the fuzzy models for the multicriterial decision making, models based on risk matrix build on the base of combination between the severity and the probability of maximum admissible consequence. These methodologies present the following steps for applying: familiarising with the activity in study, establishing the adequate method of risk assessment, building the model of risk assessment for the activity or objective in study, developing the applications of the proposed model. Applying this methodology to isotopic separation plants have led to: analysis of operation events and establishing of principal types of events potentially dangerous, analysis of human error in these plant operations and operating experience assessment, technical specifications for optimisation by probabilistic safety assessment, reliability analysis and development of reliability and exploitation of events database, post accident events analysis (releases, fires, explosions) and mathematical modelling of dispersion in atmosphere of dangerous substances. The risk concept being complex and with multiple implications, is not the case of a rigid approaching neither of existence of some methods universally valid. Because of these reasons, choosing of the most appropriate method for the risk assessment of an activity, leads to a solution in useful time, of some problems with economic, social

Automation system for operation of nuclear power plant

International Nuclear Information System (INIS)

Kinoshita, Mitsuo; Fukuzaki, Koji; Kato, Kanji

1991-01-01

The automation system comprises a general monitor control device incorporating a plurality of emergency operation plannings concerning an automatic processing, and judging whether the operation is to be conducted or not depending on the plannings based on the data planed by a plant, a control device for controlling the plant in accordance with the planning when monitor control device judges that the operation should be done due to the emergency operation plannings and an operation planning device aiding the formation of the operation plannings. When the state of the power plant exceeds a normal control region, the reactor power is lowered automatically by so much as a predetermined value or to a predetermined level, to automatically return the plant state to the normal control region. In this way, the plant operation efficiency can be improved. Further, after automatic operation, since operation plannings for recovering original operation plannings are prepared efficiently and recovered operation plannings are started in a short period of time, the operators' burden can be mitigated and power saving can be attained. (N.H.)

3. International Conference on Nuclear Power Plant Life Management (PLiM) for Long Term Operations (LTO). Keynotes, papers, presentations, posters

International Nuclear Information System (INIS)

2012-01-01

The world's fleet of nuclear power plants is, on average, more than 20 years old. Even though the design life of a nuclear power plant is typically 30-40 years, many plants will operate in excess of their design lives, provided that nuclear power plant engineers demonstrate by analysis, equipment and system upgrades, increased vigilance, testing and ageing management that the plant will operate safely. In the operation of nuclear power plants, safety should always be the prime consideration. Plant operators and regulators must always ensure that plant safety is maintained and, where possible, enhanced during its operating lifetime. Nuclear power plant life management (PLiM) has gained increased attention over the past decade, and effective ageing management of systems, structures and components (SSCs) is a key element in PLiM for the safe and reliable long term operation of nuclear power plants. A PLiM programme is an effective tool that allows an operator to safely and cost effectively manage ageing effects in SSCs for long term operation (LTO). A PLiM programme helps facilitate decisions concerning when and how to repair, replace or modify SSCs in an economically optimized way, while assuring that a high level of safety is maintained. The option for extended nuclear power plant operation has been recognized by operators and regulators alike, as evidenced in the number of licence renewal programmes that are being developed by Member States. After the severe accident at the Fukushima Daiichi nuclear power plant, the safe operation of nuclear power plants has become even more important; not only in terms of technical or ageing issues, but also in terms of management system and qualified workforce related issues. Application of an integrated management system and structured workforce planning are needed throughout the plant life in order to ensure effective plant organization and management. The IAEA organized the first and second International Conference on Nuclear

Operating plant safety analysis needs

International Nuclear Information System (INIS)

Young, M.Y.; Love, D.S.

1992-01-01

The primary objective for nuclear power station owners is to operate and manage their plants safely. However, there is also a need to provide economical electric power, which requires that the unit be operated as efficiently as possible, consistent with the safety requirements. The objectives cited above can be achieved through the identification and use of available margins inherent in the plant design. As a result of conservative licensing and analytical approaches taken in the past, many of these margins may be found in the safety analysis limits within which plants currently operate. Improvements in the accuracy of the safety analysis, and a more realistic treatment of plant initial and boundary conditions, can make this margin available for a variety of uses which enhance plant performance, help to reduce O and M costs, and may help to extend licensed operation. Opportunities for improvement exist in several areas in the accident analysis normally performed for Chapter 15 of the FSAR. For example, recent modifications to the ECCS rule, 10CFR50.46 and Appendix K, allow use of margins previously unavailable in the analysis of the Loss of Coolant Accident (LOCA). To take advantage of this regulatory change, new methods are being developed to analyze both the large and small break loss of coolant accident (LOCA). As this margin is used, enhancements in the analysis of other transients will become necessary. The paper discusses accident analysis methods, future development needs, and analysis margin utilization in specific accident scenarios

Upgrading of operation and maintenance. Lessons learned by ENEL- Nuclear Plant Management

International Nuclear Information System (INIS)

Bolla, Giuseppe; Panini, Giulio

1999-01-01

A presentation and general information on ENEL are given. The Italian Authority for Electric Energy (Ente Nazionale per l'Energia Electrica - ENEL), entirely owned by the Italian Ministry of Treasury, is the third largest utility in the world after EDF of France and TEPCO of Japan. The following figures are featuring its size: - Net maximum capacity = 52.463 GW; - Power generation = 182,500 GW h; - Customer = 28.2 Million; - Hydroelectric power plants = 651 (16.327 MW); - Thermoelectric power units = 206 (35,666 MW); - Geothermal power units = 36 (470 MW). The ENEL core business consists of generation, transmission, distribution and sale throughout Italy of electric power produced from any source as well as the importation and exportation of electric power and the co-ordination of operational and planning activities in order to ensure adequate availability throughout Italian territory of electric power at minimum cost. Before the decision taken for political reason by Italian Government in 1988 to terminate nuclear power plants operation and construction, 4 NPPs have been successfully operated. The whole production of the four plants has been about 90 billion kWh. The management experience for these plants has been good, both for plant availability and safety. No operating events occurred arising any risk for workers, population and environment. The Chernobyl power plant accident induced Italy to promote the 'nuclear referendum' in November 1987. Following the referendum the nuclear power production was interrupted. After 1988 the following nuclear activities has been carried out: - plant safe conservation, decommissioning planning, cost evaluation and safe enclosure preparation; - investigation for waste treatment methods; - participation in requirement definition and design activity for next NPP generation. A specific experience has been accumulated in the decommissioning of Italian NPPs, due to their anticipated shutdown, in particular in the field of

Maine Yankee: Making the Transition from an Operating Plant to an Independent Spent Fuel Storage Installation (ISFSI)

International Nuclear Information System (INIS)

Norton, W.; McGough, M. S.

2002-01-01

The purpose of this paper is to describe the challenges faced by Maine Yankee Atomic Power Company in making the transition from an operating nuclear power plant to an Independent Spent Fuel Storage Installation (ISFSI). Maine Yankee (MY) is a 900-megawatt Combustion Engineering pressurized water reactor whose architect engineer was Stone and Webster. Maine Yankee was put into commercial operation on December 28, 1972. It is located on an 820-acre site, on the shores of the Back River in Wiscasset, Maine about 40 miles northeast of Portland, Maine. During its operating life, it generated about 1.2 billion kilowatts of power, providing 25% of Maine's electric power needs and serving additional customers in New England. Maine Yankee's lifetime capacity factor was about 67% and it employed more than 450 people. The decision was made to shutdown Maine Yankee in August of 1997, based on economic reasons. Once this decision was made planning began on how to accomplish safe and cost effective decommissioning of the plant by 2004 while being responsive to the community and employees

Nuclear power plant operational data compilation system

International Nuclear Information System (INIS)

Silberberg, S.

1980-01-01

Electricite de France R and D Division has set up a nuclear power plant operational data compilation system. This data bank, created through American documents allows results about plant operation and operational material behaviour to be given. At present, French units at commercial operation are taken into account. Results obtained after five years of data bank operation are given. (author)

Nuclear Power Plant Operating Experience from the IAEA/NEA International Reporting System for Operating Experience, 2005-2008

International Nuclear Information System (INIS)

2010-06-01

The fundamental objective of the Incident Reporting System (IRS) is to contribute to improving the safety of commercial nuclear power plants which are operated worldwide. This fourth publication, covering the period 2005-2008, follows on the success of the previous three. It highlights important lessons learned based on a review of the approximately 200 event reports received from the participating countries over this period. The book is written both for a non-technical audience and for senior officials in industry and government who have decision making roles in the nuclear power industry.

Intelligent decision-making models for production and retail operations

CERN Document Server

Guo, Zhaoxia

2016-01-01

This book provides an overview of intelligent decision-making techniques and discusses their application in production and retail operations. Manufacturing and retail enterprises have stringent standards for using advanced and reliable techniques to improve decision-making processes, since these processes have significant effects on the performance of relevant operations and the entire supply chain. In recent years, researchers have been increasingly focusing attention on using intelligent techniques to solve various decision-making problems. The opening chapters provide an introduction to several commonly used intelligent techniques, such as genetic algorithm, harmony search, neural network and extreme learning machine. The book then explores the use of these techniques for handling various production and retail decision-making problems, such as production planning and scheduling, assembly line balancing, and sales forecasting.

Construction and operation of biogas plants. Bau und Betrieb von Biogasanlagen

Energy Technology Data Exchange (ETDEWEB)

Koenig, F. von

1985-01-01

Biogas utilisation in agriculture has increased considerably as a consequence of the energy crisis. So far, energy production was the most important aspect, and the high-quality natural fertilizer offered by the fermentation residues was commonly neglected. This fertilizer is an effective substitute for commercial fertilizers and thus contributes to the reduction of environmental pollution. The book discusses the chemical and biological mechanisms, the criteria of selection for plants and materials, optimum gas production techniques, uses of the product gas, and the advantages and properties of the biofertilizer produced. Planning procedures, design, construction, function and performance of several biogas production plants now in operation are described. Hints are given for do-it-yourself construction, as are cost-benefit calculations and decision aids for construction.

Knowledge representation for integrated plant operation and maintenance

DEFF Research Database (Denmark)

Lind, Morten

2010-01-01

Integrated operation and maintenance of process plants has many advantages. One advantage is the improved economy obtained by reducing the number of plant shutdowns. Another is to increase reliability of operation by monitoring of risk levels during on-line maintenance. Integrated plant operation...... and maintenance require knowledge bases which can capture the interactions between the two plant activities. As an example, taking out a component or a subsystem for maintenance during operation will require a knowledge base representing the interactions between plant structure, functions, operating states...... and goals and incorporate knowledge about redundancy and reliability data. Multilevel Flow Modeling can be used build knowledge bases representing plant goals and functions and has been applied for fault diagnosis and supervisory control but currently it does not take into account structural information...

Maintenance Issues in Long Term Operation of Nuclear Power Plant

International Nuclear Information System (INIS)

Contri, P.; Bieth, M.; Rieg, C.

2006-01-01

Due to current social and economical framework, in last years many nuclear power plant owners started a program for the Long Term Operation (LTO)/PLEX (Plant Life Extension) of their older nuclear facilities. This process has many nuclear safety implications, other than strategic and political ones. The need for tailoring the available safety assessment tools to such applications has become urgent in recent years and triggered many research actions. The review of regular maintenance and ageing management programs are tools widely used in LTO/PLEX context in many Countries. However, most of these tools are rather general and in many cases they need reshaping in an LTO/PLEX framework before application, with focus to the safety implications of the LTO/PLEX. Many Countries and plants radically modified their maintenance rules towards a condition based approach as a precondition for the implementation of LTO/PLEX programs. In 2004 a network of European Organisations operating Nuclear Power Plants, SENUF, under the coordination of the JRC-IE, carried out an extensive questionnaire on maintenance practice in their facilities aiming at capturing the aspects of the maintenance programs where research is mostly needed. This paper uses some results of the questionnaire, which was not oriented to LTO/PLEX, to draw some conclusions on how the current maintenance programs could support a potential LTO/PLEX, among the other programs running at NPPs. In this sense, it is spin-off of the SENUF WG on maintenance. The paper aims at identifying the technical attributes of the maintenance programs more directly affecting the decision for a long-term safe operation of a nuclear facility, the issues related to their implementation and safety review. The paper includes an analysis of the questionnaire circulated among the SENUF participants and a discussion on the implications of optimised maintenance programs in existing plants. Some examples at WWER plants taken by sources other than

Prototype plant for nuclear process heat (PNP) - operation of the pilot plant for hydrogasification of coal

International Nuclear Information System (INIS)

Bruengel, N.; Dehms, G.; Fiedler, P.; Gerigk, H.P.; Ruddeck, W.; Schrader, L.; Schumacher, H.J.

1988-04-01

The Rheinische Braunkohlenwerke AG developed the process of hydrogasification of coal in a fluidized bed for generation of SNG. On basis of test results obtained in a semi-technical pilot plant of a through-put of 250 kg/h dried coal a large pilot plant was erected processing 10 t/h dried brown coal. This plant was on stream for about 14700 h, of which about 7800 h were with gasifier operation; during this time about 38000 t of dried brown coal of the Rhenish district were processed containing 4 to 25% of ash. At pressures of 60 to 120 bar and temperatures of 800 to 935 0 C carbon conversion rates up to 81 percent and methane amounts of 5000 m 3 (STP)/h were reached. The decisive parameter for methane generation was the hydrogen/coal-ratio. Even at high moisture contents, usually diminishing the methane yield from the coal essentially, by high hydrogen/coal-ratios high methane yields could be obtained. The gasifier itself caused no troubles during the total time operation. Difficulties with the original design of the residual char cooler could be overcome by change-over from water injection to liquid carbon dioxide. The design of the heat recovery system proved well. Alltogether so the size increasement of the gasifier from the semi-technical to the large pilot plant as well as the harmonization of gas generation and gas refining was proved. (orig.) With 20 refs., 20 tabs., 81 figs [de

Psychological characteristics of licensed nuclear power plant operators

International Nuclear Information System (INIS)

Sajwaj, T.; Ford, T.; McGee, R.K.

1987-01-01

The safe production of electricity by nuclear power plants has been the focus of considerable attention. Much of this concern has been focused on equipment and procedural issues, with less attention to the psychological factors that affect the operations staff of the plants, i.e., those individuals who are most directly responsible for a plant's operations. Stress and type A qualities would be significant for these individuals because of their relationships to job performance and health. Of equal significance would be work-related factors, such as job involvement and work pressure. Also of interest would be hostile tendencies because of the need for cooperation and communications among operations staff. Two variables could influence these psychological factors. One is the degree of responsibility for a plant's nuclear reactors. The individuals with the greatest responsibility are licensed by the US Nuclear Regulatory Commission (NRC). There are also individuals with less direct responsibilities who are not licensed. A second variable is the operating status of the plant, whether or not the plant is currently producing electricity. Relative to ensuring the safe operation of nuclear power plants, these data suggest a positive view of licensed operators. Of interest are the greater stress scores in the licensed staff of the operating plant in contrast with their peers in the nonoperating plant

Plant operation state monitoring system

International Nuclear Information System (INIS)

Sakai, Masanori; Babuchi, Katsumi; Arato, Toshiaki

1994-01-01

The system of the present invention accurately monitors a plant operation state of a plant, such as a nuclear power plant and a thermal power plant by using high temperature water, based on water quality informations. That is, water quality informations for the objective portion by using an electrochemical water quality sensor disposed in the objective portion to be monitored in the plant are continuously extracted for a predetermined period of time. Water quality is evaluated based on the extracted information. Obtained results for water quality evaluation and predetermined reference values of the plant operation handling are compared. Necessary part among the results of the measurement is displayed or recorded. The predetermined period of time described above is a period that the water quality information reaches at least a predetermined value or a period that the predetermined value is estimated by the water quality information, and it is defined as a period capable of measuring the information for three months continuously. The measurement is preferably conducted continuously in a period up to each periodical inspection on about every one year. (I.S.)

The critical safety functions and plant operation

International Nuclear Information System (INIS)

Corcoran, W.R.; Church, J.F.; Cross, M.T.; Guinn, W.M.; Porter, N.J.

1981-01-01

The operator's role in nuclear safety is outlined and the concept of ''safety functions'' introduced. Safety functions are a group of actions that prevent core melt or minimize radiation releases to the general public. They can be used to provide a hierarchy of practical plant protection that an operator should use. The plant safety evaluation uses four inputs in predicting the results of an event: the event initiator, the plant design, the initial plant conditions and setup, and the operator actions. If any of these inputs are not as assumed in the evaluation, confidence that the consequences will be as predicted is reduced. Based on the safety evaluation, the operator has three roles in assuring that the consequences of an event will be no worse than the predicted acceptable results: Maintain plant setup in readiness to properly respond. Operate the plant in a manner such that fewer, milder events minimize the frequency and the severity of adverse events. Monitor the plant to verify that the safety functions are accomplished. The operator needs a systematic approach to mitigating the consequences of an event. The concept of safety functions introduces this systematic approach and presents a hierarchy of protection. If the operator has difficulty identifying an event for any reason, the systematic safety function approach allows accomplishing the overall path of mitigating consequences. Ten functions designed to protect against core melt, preserve containment integrity, prevent indirect release of radioactivity, and maintain vital auxiliaries needed to support the other safety functions are identified

Operation of Finnish nuclear power plants

International Nuclear Information System (INIS)

Lehtinen, Pekka

1987-05-01

These general reviews of the operation of the Finnish nuclear power plants concentrate on such events and discoveries related to reactor and radiation safety that the regulatory body, the Finnish Centre for Radiation and Nuclear Safety, regards as noteworthy. The report also includes a summary of the radiation safety of the personnel and the environment, as well as tabulated data on the production and load factors of the plants. In the report period, no event essentially degraded plant safety nor posed a radiation hazard to the perssonnel or the environment. For remedying certain defects found in the administrative procedures concerning plant operation and maintenance, the Loviisa power plant was shut down for several days

CANDU 9 operator plant display system

International Nuclear Information System (INIS)

Trueman, R.; Webster, A.; MacBeth, M.J.

1997-01-01

To meet evolving client and regulatory needs, AECL has adopted an evolutionary approach to the design of the CANDU 9 control centre. That is, the design incorporates feedback from existing stations, reflects the growing diversity in the roles and responsibilities of the operating staff, and reduces costs associated with plant capital and operations, maintenance and administration (OM and A), through the appropriate introduction of new technologies. Underlying this approach is a refined engineering design process that cost-effectively integrates operational feedback and human factors engineering to define the operating staff information and information presentation requirements. Based on this approach, the CANDU 9 control centre will provide utility operating staff with the means to achieve improved operations and reduced OM and A costs. One of the design features that will contribute to the improved operational capabilities of the control centre is a new Plant Display System (PDS) that is separate from the digital control system. The PDS will be used to implement non-safety panel, and console video display systems within the CANDU 9 main control room (MCR). This paper presents a detailed description of the CANDU 9 Plant Display System and features that provide increased operational capabilities. (author)

Integrated approach to optimize operation and maintenance costs for operating nuclear power plants

International Nuclear Information System (INIS)

2006-06-01

In the context of increasingly open electricity markets and the 'unbundling' of generating companies from former utility monopolies, an area of major concern is the economic performance of the existing fleet of nuclear power plants. Nuclear power, inevitably, must compete directly with other electricity generation sources. Coping with this competitive pressure is a challenge that the nuclear industry should meet if the nuclear option is to remain a viable one. This competitive environment has significant implications for nuclear plant operations, including, among others, the need for the more cost effective management of plant activities, and the greater use of analytical tools to balance the costs and benefits of proposed activities, in order to optimize operation and maintenance costs, and thus insure the economic competitiveness of existing nuclear power plants. In the framework of the activities on Nuclear Economic Performance Information System (NEPIS), the IAEA embarked in developing guidance on optimization of operation and maintenance costs for nuclear power plants. The report was prepared building on the fundamental that optimization of operation and maintenance costs of a nuclear power plant is a key component of a broader integrated business strategic planning process, having as overall result achievement of organization's business objectives. It provides advice on optimization of O and M costs in the framework of strategic business planning, with additional details on operational planning and controlling. This TECDOC was elaborated in 2004-2005 in the framework of the IAEA's programme on Nuclear Power Plant Operating Performance and Life Cycle Management, with the support of two consultants meetings and one technical meeting and based on contributions provided by participants. It can serve as a useful reference for the management and operation staff within utilities, nuclear power plant operators and regulators and other organizations involved in

An innovative concept for handling and operation of the wastewater treatment plant of Cottbus

International Nuclear Information System (INIS)

Spiller, K.; Schmitt, J.

1994-01-01

A new concept for handling and operating the wastewater treatment plant of Cottbus, with computerized modelling and an expert system as integral parts of process analysis and decision-making, is developed. Optimized plant operation and process stability is to be achieved by conrolling process-dependent dosage of wastewater coming from sludge treatment and from faecal wastewater. With the treatment plant still being built, a thorough analysis of the influent and the resulting process conditions is done, using the computerized model. Results and consequences for process optimization are presented in this article. Special attention has to be given to load smoothing and optimization of denitrification, influencing process stability and quality. Thereby not only the legal requirements can be fulfilled but improvement of effluent quality also could be achieved, reducing total nitrogen in the effluent by as much as 50%, lowering wastewater treatment costs by allowing lower control levels and fees to be payed. (orig.) [de

Artificial intelligence aid to efficient plant operations

International Nuclear Information System (INIS)

Wildberger, A.M.; Pack, R.W.

1987-01-01

As the nuclear power industry matures, it is becoming more and more important that plants be operated in an efficient, cost-effective manner, without, of course, any decrease in the essential margins of safety. Indeed, most opportunities for improved efficiency have little or no relation to nuclear safety, but are based on trade-offs among operator controllable parameters both within and external to the reactor itself. While these trade-offs are describable in terms of basic physical theory, thermodynamics, and the mathematics of control systems, their actual application is highly plant specific and influenced even by the day-to-day condition of the various plant components. This paper proposes the use of artificial intelligence techniques to construct a computer-based expert assistant to the plant operator for the purpose of aiding him in improving the efficiency of plant operation on a routine basis. The proposed system, which only advises the human operator, seems more amenable to the current regulatory approach than a truly automated control system even if the latter provides for manual override

Development of JOYO plant operation management expert tool

Energy Technology Data Exchange (ETDEWEB)

Michino, Masanobu; Sawada, Makoto [Power Reactor and Nuclear Fuel Development Corp., Oarai, Ibaraki (Japan). Oarai Engineering Center

1995-03-01

Operation and maintenance support systems for JOYO are being developed in order to keep the stable and safe operation of JOYO and to improve operational reliability of future FBR plants. As one of the systems, an operation support system named JOYPET has been developing and applied. The system supports the plant management works of JOYO which are necessary for much manpower and knowledge of the plant. The plant management of JOYO was able to improve its reliability and reduce manpower by using this system. As a final step, a judgment function based on the accumulated plant management rule of JOYO will be developed and applied. The function judges the plant condition which allows to start the maintenance works or not. (author).

Dynamic operational risk management at industrial irradiation plants

International Nuclear Information System (INIS)

Wieland, Patricia; Lustosa, Leonardo J.

2010-01-01

Although feasibility studies indicate that industrial irradiation can be sound business, some initiatives fail in few years. In Brazil, the operation of some industrial irradiation plants has been discontinued in spite of the growing export market for tropical fruits like mangoes and papayas, of which Brazil is one of the major producers. This paper discusses the overall aspects of the food irradiation in Brazil, singles out dynamic operation risk management as an important need and provides suggestions for further developments. This research work involves literature review as well as interviews with irradiation industry stake holders in order to identify the ORs and to assess the situation in a logical and integrated way. The results show that public acceptance is not a major issue for the food preservation industry in Brazil. On the contrary, evidences show that there is public support, provided that information on the subject is disseminated among consumers. Need for improvements have been detected in the areas of industrial operational risk management, external relations for export, and regulatory issues, among others to support decision making in establishing and developing industrial food irradiation capabilities to serve Brazilian tropical fruit exports. (author)

Operation and maintenance in Genkai PWR Plant

International Nuclear Information System (INIS)

Ohta, Shojiro

1984-01-01

The No.1 PWR plant with 559 MW capacity in the Genkai Nuclear Power Station, Kyushu Electric Power Co., Inc., required about 115 days for the regular inspection in fiscal 1982 and thereafter, although more maintenance work was done. But No.2 plant of the same type required not more than 80 days. In most cases, the period of one operation cycle was from 10 to 12 months, but in the third operation cycle of No.2 plant, it is expected to be 13 months. The capacity ratio of the whole power station was 75.2% at the end of fiscal 1983. These operational records all exceeded the Japanese average. The plants are two-loop Westinghouse type PWRs, and No.1 plant started the commercial operation of anti h and the increment of P 0 + . (author) apacity ratio of No.1 plant was 71.6%, and that of No.2 plant was 85.5%. The intergranular attack on steam generator tubes was found first in the fifth regular inspection, and also in the sixth and seventh inspections, and the faulty tubes were plugged. The prevention of its spread is the largest problem. The in-service quality assurance activity, the personnel training program and the effort of upgrading the plant availability are reported. (Kako, I.)

Computer aids for plant operators

International Nuclear Information System (INIS)

Joly, J.P.

1992-01-01

For some time, particularly since the TMI accident, nuclear power plant operators have been aware of the difficulties involved in diagnosing accidents and returning plants to their stable, safe operating mode. There are various possible solutions to these problems: improve control organization during accident situations, rewrite control procedures, integrate safety engineers in shifts, improve control rooms, and implement additional computer aids. The purpose of this presentation is to describe the efforts undertaken by EDF over the last few years in this field

Fuzzy logics acquisition and simulation modules for expert systems to assist operator's decision for nuclear power stations

International Nuclear Information System (INIS)

Averkin, A.A.

1994-01-01

A new type of fuzzy expert system for assisting the operator's decisions in nuclear power plant system in non-standard situations is proposed. This expert system is based on new approaches to fuzzy logics acquisition and to fuzzy logics testing. Fuzzy logics can be generated by a T-norms axiomatic system to choose the most suitable to operator's way of thinking. Then the chosen fuzzy logic is tested by simulation of inference process in expert system. The designed logic is the input of inference module of expert system

Modelling leaf, plant and stand flammability for ecological and operational decision making

Science.gov (United States)

Zylstra, Philip

2014-05-01

Numerous factors have been found to affect the flammability of individual leaves and plant parts; however the way in which these factors relate to whole plant flammability, fire behaviour and the overall risk imposed by fire is not straightforward. Similarly, although the structure of plant communities is known to affect the flammability of the stand, a quantified, broadly applicable link has proven difficult to establish and validate. These knowledge gaps have presented major obstacles to the integration into fire behaviour science of research into factors affecting plant flammability, physiology, species succession and structural change, so that the management of ecosystems for fire risk is largely uninformed by these fields. The Forest Flammability Model (Zylstra, 2011) is a process-driven, complex systems model developed specifically to address this disconnect. Flame dimensions and position are calculated as properties emerging from the capacity for convective heat to propagate flame between horizontally and vertically separated leaves, branches, plants and plant strata, and this capacity is determined dynamically from the ignitability, combustibility and sustainability of those objects, their spatial arrangement and a vector-based model of the plume temperature from each burning fuel. All flammability properties as well as the physics of flame dimensions, angle and temperature distributions and the vertical structure of wind within the plant array use published sub-models which can be replaced as further work is developed. This modular structure provides a platform for the immediate application of new work on any aspect of leaf flammability or fire physics. Initial validation of the model examined its qualitative predictions for trends in forest flammability as a function of time since fire. The positive feedback predicted for the subalpine forest examined constituted a 'risky prediction' by running counter to the expectations of the existing approach, however

MODELLING OF DECISION MAKING OF UNMANNED AERIAL VEHICLE'S OPERATOR IN EMERGENCY SITUATIONS

Directory of Open Access Journals (Sweden)

Volodymyr Kharchenko

2017-03-01

Full Text Available Purpose: lack of recommendation action algorithm of UAV operator in emergency situations; decomposition of the process of decision making (DM by UAV’s Operator in emergency situations; development of the structure of distributed decision support system (DDSS for remotely piloted aircraft; development of a database of local decision support system (DSS operators Remotely Piloted Aircraft Systems (RPAS; working-out of models DM by UAV’s Operator. Methods: Algoritm of actions of UAV operator by Wald criterion, Laplace criterion, Hurwitz criterion. Results: The program "UAV_AS" that gives to UAV operator recommendations on how to act in case of emergency. Discussion: The article deals with the problem of Unmanned Aerial Vehicles (UAV flights for decision of different tasks in emergency situation. Based on statistical data it was analyzing the types of emergencies for unmanned aircraft. Defined sequence of actions UAV operator and in case of emergencies.

Operation of Finnish nuclear power plants

International Nuclear Information System (INIS)

Lehtinen, Pekka

1987-07-01

These general reviews of the operation of the Finnish nuclear power plants concentrate on such events and discoveries related to reactor and radiation safety that the regulatory body, the Finnish Centre for Radiation and Nuclear Safety, regards as noteworthy. The report also includes a summary of the radiation safety of the personnel and the environment, as well as tabulated data on the production and load factors of the plants. No event in the report period, or in the whole year of 1986, essentially degraded plant safety nor posed a radiation hazard to the personnel or the environment. For remedying certain defects found in the adminstrative procedures concerning plant operation and maintenance, the Loviisa power plant was shut down for several days in September

Modeling Operating Modes for the Monju Nuclear Power Plant

DEFF Research Database (Denmark)

Lind, Morten; Yoshikawa, Hidekazu; Jørgensen, Sten Bay

2012-01-01

The specification of supervision and control tasks in complex processes requires definition of plant states on various levels of abstraction related to plant operation in start-up, normal operation and shut-down. Modes of plant operation are often specified in relation to a plant decomposition in...... for the Japanese fast breeder reactor plant MONJU....

Decision support in supervisory control

International Nuclear Information System (INIS)

Rasmussen, J.; Goodstein, L.P.

1985-08-01

It is argued that the supervisory control of complex industrial processes having a potential for serious consequences in case of accidents requires careful consideration of the allocation of decision making between the three main agents of control; namely the designer, the operator and the automatic control system. In particular, it is advocated that instead of continuing their efforts to make their preplanning of responses and countermeasures more and more complete and restricting the operator's initiative, designers should take advantage of modern information technology to make available to the operators their conceptual models and their processing resources so as to allow the operators to function as their extended arm in coping with the plant. Such an interactive decision making activity would thus benefit from this simultaneous availability of the design basis, up-to-date knowledge of plant status and accumualted operational experience. (author)

Advanced operation strategy for feed-and-bleed operation in an OPR1000

International Nuclear Information System (INIS)

Kim, Bo Gyung; Yoon, Ho Joon; Kim, Jaewhan; Kang, Hyun Gook

2016-01-01

Highlights: • Advanced operating strategy covers all necessary conditions for F&B operation. • Advanced operating strategy identifies the urgency of F&B operation. • An advanced operating strategy for F&B operation is developed using a decision tree. • Human error probability is re-estimated based on a thermohydraulic analysis and K-HRA method. • An advanced operation strategy provides indications under various plant situations. - Abstract: When the secondary side is unavailable in a pressurized water reactor (PWR), heat from the core will accumulate in the primary side causing core damage. In this situation a heat removal mechanism called feed-and-bleed operation (F&B operation) must be used, which is a process of directly cooling the primary reactor cooling system (RCS). However, conventional operation strategy in emergency operating procedures (EOPs) does not cover all possible conditions to initiate F&B operation. If the EOP informs on the urgency of F&B operation, operators will be able to more clearly make decisions regarding F&B operation initiation. In order to cover all possible scenarios for F&B operation and systematically inform its urgency, an advanced operating strategy using a decision tree is developed in this study. The plant condition can be classified according to failure of secondary side, RCS pressure condition, injectable inventory to RCS, and remaining core inventory. RCS pressure, core level, and RCS temperature are representative indicators which provide information regarding the initiation of F&B operation. Indicators can be selected based on their detectability and quantification, and a decision tree is developed according to combinations of indicators. To estimate the effects of the advanced operation strategy, human error probability (HEP) of F&B operation is re-estimated based on a thermohydraulic analysis. The available time for operators to initiate F&B operation is also re-estimated to obtain more realistic data. This

Preparation and practice for nuclear power plant operation

International Nuclear Information System (INIS)

Wu Xuesong; Lu Tiezhong

2015-01-01

The operational preparation of the nuclear power plant is an important work in nuclear power plant production preparation. Due to the construction period of nuclear power plant from starting construction to production is as long as five years, the professional requirements of nuclear power operation are very strict, and the requirements for nuclear safety are also extremely high. Especially after the Fukushima accident, higher requirements for the safe operation of nuclear power plant are posed by competent authorities of the national level, regulatory authorities and each nuclear power groups. Based on the characteristics of the construction phase of nuclear power plant and in combination with engineering practice, this paper expounds the system established in the field of nuclear power plant operation and generally analyses the related management innovation. (authors)

Integration of plant life management in operation and maintenance

International Nuclear Information System (INIS)

Hutin, Jean-Pierre

2002-01-01

Full text: 1 - INTRODUCTION. Electricite de France is now operating 58 PWR nuclear power plants which produce 75% of french electricity. Besides maintaining safety and availability on a routine basis, it is outmost important to protect the investment. Indeed, such an asset is a tremendous advantage just as the company is going to face the new european electricity market. That is the reason why EDF is devoting important effort to implement ageing management as an integral part of operation and maintenance programs. But it must be recognized that NPP lifetime is not threatened only by component-related problems: other less technical issues must be seriously considered like industrial support, information system, skilled people, public acceptance, etc. 2 - LIFE MANAGEMENT POLICY. In France, there is no limited licensing period for NPPs. The life management policy of nuclear power plants is based on three principles: - safe and cost-effective operation, looking for excellence in daily activities, with an effective experience feedback organisation taking advantage of the high level of standardization of the units, - every ten years, a new set of safety standards, a complete review of each facility and an upgrading of its safety level through appropriate modifications while maintaining unit standardization in all the fleet, - a Life Management Program, at corporate level, which permanently scrutinizes operation and maintenance activities to identify decisions which could impair plant lifetime and which surveys research and development programs related to ageing phenomenon understanding. 3 - INTEGRATION OF LIFETIME CONCERN IN O and M ACTIVITIES. It is outmost important to take in account lifetime concern in daily operation and maintenance activities and this must be done as early as possible in plant life. Even though sophisticated assessments require engineering capacity, many good ideas may arise from plant staff. For that reason, increasing lifetime awareness of plant

Permanent cessation of Tokai power plant's operation

International Nuclear Information System (INIS)

Satoh, T.

1998-01-01

Tokai power plant (166MWe, Magnox type: GCR) is the first commercial reactor in Japan and has been kept operating stable since its commissioning in July 1996. During this period it has produced electricity of approximately 27.7 billion KWh (as of March 1997) and its stable operation has contributed greatly to the stable supply of electricity in Japan. Furthermore, technologies in various fields have been developed, demonstrated and accumulated through the construction and operation of Tokai power plant. It also contributes to training for many nuclear engineers, and constructions and operations of nuclear power stations by other Japanese power companies. As a pioneer, it has been achieved to develop and popularize Japanese nuclear power generation. On the other hand, Tokai power plant has small capacity in its electric power output, even though the size of the reactor and heat exchangers are rather bigger than those of LWR due to the characteristics of GCR. Therefore, the generation cost is higher than the LWR. Since there is no plant whose reactor type is the same as that of Tokai power plant, the costs for maintenance and fuel cycle are relatively higher than that of LWR. Finally we concluded that the longer we operate it, the less we can take advantage of it economically. As a result of the evaluation for the future operation of Tokai power plant including the current status for supply of electricity by the Japanese utilities and study of decommissioning by Japanese government, we decided to have a plan of stopping its commercial operation of Tokai power plant in the end of March, 1998, when we completely consume its fuel that we possess. From now on, we set about performing necessary studies and researches on the field of plant characterization, remote-cutting, waste disposal for carrying out the decommissioning of Tokai power plant safely and economically. We are going to prepare the decommissioning planning for Tokai power plant in a few years based on the

Operator training simulator for nuclear power plant

International Nuclear Information System (INIS)

Shiozuka, Hiromi

1977-01-01

In nuclear power plants, training of the operators is important. In Japan, presently there are two training centers, one is BWR operation training center at Okuma-cho, Fukushima Prefecture, and another the nuclear power generation training center in Tsuruga City, Fukui Prefecture, where the operators of PWR nuclear power plants are trained. This report describes the BWR operation training center briefly. Operation of a nuclear power plant is divided into three stages of start-up, steady state operation, and shut down. Start-up is divided into the cold-state start-up after the shut down for prolonged period due to periodical inspection or others and the hot-state start-up from stand-by condition after the shut down for a short time. In the cold-state start-up, the correction of reactivity change and the heating-up control to avoid excessive thermal stress to the primary system components are important. The BWR operation training center offers the next three courses, namely beginner's course, retraining course and specific training course. The training period is 12 weeks and the number of trainees is eight/course in the beginner's course. The simulator was manufactured by modeling No. 3 plant of Fukushima First Nuclear Power Station, Tokyo Electric Power Co. The simulator is composed of the mimic central control panel and the digital computer. The software system comprises the monitor to supervise the whole program execution, the logic model simulating the plant interlock system and the dynamic model simulating the plant physical phenomena. (Wakatsuki, Y.)

Academic training for nuclear power plant operators

International Nuclear Information System (INIS)

Jones, D.W.

1982-01-01

In view of the increasing emphasis being placed upon academic training of nuclear power plant operators, it is important that institutions of higher education develop and implement programs which will meet the educational needs of operational personnel in the nuclear industry. Two primary objectives must be satisfied by these programs if they are to be effective in meeting the needs of the industry. One objective is for academic quality. The other primary objective is for programs to address the specialized needs of the nuclear plant operator and to be relevant to the operator's job. The Center for Nuclear Studies at Memphis State University, therefore, has developed a total program for these objectives, which delivers the programs, and/or appropriate parts thereto, at ten nuclear plant sites and with other plants in the planning stage. The Center for Nuclear Studies program leads to a Bachelor of Professional Studies degree in nuclear industrial operations, which is offered through the university college of Memphis State University

Application of ann-based decision making pattern recognition to fishing operations

Energy Technology Data Exchange (ETDEWEB)

Akhlaghinia, M.; Torabi, F.; Wilton, R.R. [University of Regina, Saskatchewan (Canada). Faculty of Engineering. Dept. of Petroleum Engineering], e-mail: Farshid.Torabi@uregina.ca

2010-10-15

Decision making is a crucial part of fishing operations. Proper decisions should be made to prevent wasted time and associated costs on unsuccessful operations. This paper presents a novel model to help drilling managers decide when to commence and when to quit a fishing operation. A decision making model based on Artificial Neural Network (ANN) has been developed that utilizes Pattern Recognition based on 181 fishing incidents from one of the most fish-prone fields of the southwest of Iran. All parameters chosen to train the ANN-Based Pattern Recognition Tool are assumed to play a role in the success of the fishing operation and are therefore used to decide whether a fishing operation should be performed or not. If the tool deems the operation suitable for consideration, a cost analysis of the fishing operation can then be performed to justify its overall cost. (author)

A generic accounting model to support operations management decisions

NARCIS (Netherlands)

Verdaasdonk, P.J.A.; Wouters, M.J.F.

2001-01-01

Information systems are generally unable to generate information about the financial consequences of operations management decisions. This is because the procedures for determining the relevant accounting information for decision support are not formalised in ways that can be implemented in

Operation and maintenance of nuclear power plants

International Nuclear Information System (INIS)

Ackermann, G.

1987-01-01

This textbook gives a systematic introduction into the operational and maintenance activities in nuclear power plants with pressurized water reactors. Subjects: (1) Setup and operational behaviour of power reactors, (2) setup of nuclear power plants, (3) radiation protection and nuclear safety, (4) nuclear fuel, (5) constructional layout of nuclear power plants, (6) management, and (7) maintenance. 158 figs., 56 tabs

Operating experience with nuclear power plants 2015. Pt. 1

Energy Technology Data Exchange (ETDEWEB)

Anon.

2016-07-01

The VGB Technical Committee ''Nuclear Plant Operation'' has been exchanging operating experience about nuclear power plants for more than 30 years. Plant operators from several European countries are participating in the exchange. A report is given on the operating results achieved in 2015, events important to plant safety, special and relevant repair, and retrofit measures from Germany. The second part of this report will focus on nuclear power plant in Belgium, Finland, the Netherlands, Switzerland, and Spain.

Load-following operation of PWR plants

Energy Technology Data Exchange (ETDEWEB)

Jang, Jong Hwa; Oh, Soo Yul; Koo, Yang Hyun; Lee, Jae Han [Korea Atomic Energy Research Institute, Taejon (Korea, Republic of)

1993-12-01

The load-following operation of nuclear power plants will become inevitable due to the increased nuclear share in the total electricity generation. As a groundwork for the load-following capability of the Korean next generation PWRs, the state-of-the-art has been reviewed. The core control principles and methods are the main subject in this review as well as the impact of load-following operations on the fuel performance and on the mechanical integrity of components. To begin with, it was described what the load-following operation is and in what view point the technology should be reviewed. Afterwards the load-following method, performance and problems in domestic 900 MWe class PWRs were discussed, and domestic R and D works were summarized. Foreign technologies were also reviewed. They include Mode G and Mode X of Foratom, D and L bank method of KWU, the method using PSCEA of ABB-CE, and MSHIM of Westinghouse. The load-following related special features of Foratom`s N4 plant, KWU`s plants, ABB-CE`s Systems 80+, and Westinghouse`s AP600 were described in each technology review. The review concluded that the capability of N4 plant with Mode X is the best and the methods in System, 80+ and AP600 would require verifications for the continued and usual load-following operation. It was recommended that the load-following operation experiences in domestic PWRs under operation be required to settle down the capability for the future. In addition, a more enhanced technology is required for the Korean next generation PWR regardless what the reference plant concept is. 30 figs., 19 tabs., 75 refs. (Author).

Operator support system for nuclear power plants

International Nuclear Information System (INIS)

Mori, Nobuyuki; Tai, Ichiro; Sudo, Osamu; Naito, Norio.

1987-01-01

The nuclear power generation in Japan maintains the high capacity factor, and its proportion taken in the total generated electric power exceeded 1/4, thus it has become the indispensable energy source. Recently moreover, the nuclear power plants which are harmonious with operators and easy to operate are demanded. For realizing this, the technical development such as the heightening of operation watching performance, the adoption of automation, and the improvement of various man-machine systems for reducing the burden of operators has been advanced by utilizing electronic techniques. In this paper, the trend of the man-machine systems in nuclear power plants, the positioning of operation support system, the support in the aspects of information, action and knowledge, the example of a new central control board, the operation support system using a computer, an operation support expert system and the problems hereafter are described. As the development of the man-machine system in nuclear power plants, the upgrading from a present new central control board system PODIA through A-PODIA, in which the operational function to deal with various phenomena arising in plants and safety control function are added, to 1-PODIA, in which knowledge engineering technology is adopted, is expected. (Kako, I.)

Computing and cognition in future power plant operations

International Nuclear Information System (INIS)

Kisner, R.A.; Sheridan, T.B.

1983-01-01

The intent of this paper is to speculate on the nature of future interactions between people and computers in the operation of power plants. In particular, the authors offer a taxonomy for examining the differing functions of operators in interacting with the plant and its computers, and the differing functions of the computers in interacting with the plant and its operators

Computing and cognition in future power-plant operations

International Nuclear Information System (INIS)

Kisner, R.A.; Sheridan, T.B.

1983-01-01

The intent of this paper is to speculate on the nature of future interactions between people and computers in the operation of power plants. In particular, the authors offer a taxonomy for examining the differing functions of operators in interacting with the plant and its computers, and the differing functions of the computers in interacting with the plant and its operators

Intelligent decision support system for operators of the supply ...

African Journals Online (AJOL)

Intelligent decision support system for operators of the supply department of oil and gas extracting industry. ... PROMOTING ACCESS TO AFRICAN RESEARCH ... abnormal situations, pre-crash sensing, industrial drilling, decision-making support systems. Full Text: EMAIL FREE FULL TEXT EMAIL FREE FULL TEXT

Plant life management for long term operation of nuclear power plants

International Nuclear Information System (INIS)

2005-01-01

The world's fleet of Nuclear Power Plants (NPPs) is approximately 20 years old on average, and most plants are believed to be able to operate for 60 years or more. The design life of a NPP is typically 30 to 40 years. This may be extended by 10 to 20 years, or more, provided that the plant can demonstrate by analysis, trending, equipment and system upgrades, increased vigilance, testing, ageing management, and other means that license renewal presents no threat to public health and safety. The basic goal of Plant Life Management (PLiM) is to satisfy requirements for safe long-term supplies of electricity in an economically competitive way. The basic goal of the operating company and the owners to operate as long as economically reasonable and possible from safety point of view. PLiM is a management tool for doing that. PLiM is a system of programmes and procedures to satisfy safety requirements for safe operation and for power production in a competitive way and for time which is rational from technical and economical point of view. PLiM is not only a technical system, it is also an attitude of the operational company to keep the plant in operation as long as possible from safety and business point of view. The common objectives of PLiM assessment is to help and review the pre-conditions for PLiM and long-term operation approaches. PLiM should not be associated with extension of operational life-time of the NPP only. It is an owner's attitude and rational approach of the operating company to run the business economically and safely. The effectiveness of PLiM Programme can be assessed by three complementary kinds of assessment: self-assessment, peer review and comprehensive programme review by the plant owner/ operator. IAEA will provide the assessment service for peer review of PLiM. Preparation for a PLiM Assessment service will be initiated only after the IAEA has been formally approached by a MS and funding (e.g. an existing Technical cooperation project) has

Decision tree ensembles for online operation of large smart grids

International Nuclear Information System (INIS)

Steer, Kent C.B.; Wirth, Andrew; Halgamuge, Saman K.

2012-01-01

Highlights: ► We present a new technique for the online control of large smart grids. ► We use a Decision Tree Ensemble in a Receding Horizon Controller. ► Decision Trees can approximate online optimisation approaches. ► Decision Trees can make adjustments to their output in real time. ► The new technique outperforms heuristic online optimisation approaches. - Abstract: Smart grids utilise omnidirectional data transfer to operate a network of energy resources. Associated technologies present operators with greater control over system elements and more detailed information on the system state. While these features may improve the theoretical optimal operating performance, determining the optimal operating strategy becomes more difficult. In this paper, we show how a decision tree ensemble or ‘forest’ can produce a near-optimal control strategy in real time. The approach substitutes the decision forest for the simulation–optimisation sub-routine commonly employed in receding horizon controllers. The method is demonstrated on a small and a large network, and compared to controllers employing particle swarm optimisation and evolutionary strategies. For the smaller network the proposed method performs comparably in terms of total energy usage, but delivers a greater demand deficit. On the larger network the proposed method is superior with respect to all measures. We conclude that the method is useful when the time required to evaluate possible strategies via simulation is high.

Simulation and experimental studies of operators' decision styles and crew composition while using an ecological and traditional user interface for the control room of a nuclear power plant

International Nuclear Information System (INIS)

Meshkati, N.; Buller, B.J.; Azadeh, M.A.

1994-01-01

A traditional human factors (i.e., microergonomic) approach to complex human-machine systems is only concerned with improving the workstation (user interface) design. This approach, by ignoring the importance of the integration of the user interface with job and organizational design, results in systems which lead, at best, only to sub-optimization and are therefore inherently error- and failure-prone. Such systems, when eventually faced with the concentration of certain fault events, will suffer from this open-quotes resident pathogenclose quotes and, as such, are doomed to failure. Also, when complex technological systems, such as nuclear power plants, move from routine to non-routine (normal to emergency) operation, the controlling operators need to dynamically match the system's new requirements. This mandates integrated and harmonious changes in information presentation (display), changes in (job) performance requirements in part because of operators' inevitable involuntary transition to different levels of cognitive control, and reconfigurations of the operators' team (organizational) structure and communication. It is also demonstrated that the skill, rule, and knowledge (SRK) model, developed by Rasmussen, is a high-potential and powerful framework that could be utilized for the proposed integration purpose. The objective of this research was threefold: (1) using the SRK model, to develop an integrated information processing conceptual framework (for integration of workstation, job, and team design); (2) to evaluate the user interface component of this framework -- the ecological display; and (3) to analyze the effect of operators' individual information processing behavior and decision styles on handling plant disturbances, on their performance and preference for traditional and ecological user interfaces

Licensing operators for commercial nuclear power plants

International Nuclear Information System (INIS)

Hannon, J.N.

1988-01-01

The human element in the operation of commercial nuclear power plants is of utmost importance. Not only must the operators be technically competent in the execution of numerous complicated tasks, they must be capable of working together as a team to diagnose dynamic plant conditions to ensure that their plants are operated safely. The significance of human interaction skills and crew communications has been demonstrated most vividly in TMI and Chernobyl. It follows that the NRC must retain its high standards for licensing operators. This paper discusses activities and initiatives being employed by the NRC to enhance the reliability of its licensing examinations, and to build a highly qualified examiner work force

System dynamics modeling of social/political factors in nuclear power plant operations

International Nuclear Information System (INIS)

Hansen, K.F.; Turek, M.G.; Eubanks, C.K.

1995-01-01

The safety and performance of nuclear power plants are a function of many technical factors such as initial design, service and maintenance programs, and utility investment in improvements. Safety and performance are also a function of the social/political influences that affect requirements on personnel, practices and procedures, and resource availability. This paper describes a process for constructing models of the social/political influences on plant operations using the system dynamics technique. The model incorporates representation of internal utility actions and decisions as affected by external factors such as public opinion, intervenor actions, safety and economic regulation, and the financial community. The feedback between external agents and plant performance is explicitly modeled. The resulting model can be used to simulate performance under a variety of different external and internal policy choices. In particular, the model can be used to study means of improving performance in response to externally imposed regulations

Operations quality assurance for nuclear power plants

International Nuclear Information System (INIS)

1987-01-01

This standard covers the quality assurance of all activities concerned with the operation and maintenance of plant equipment and systems in CANDU-based nuclear power plants during the operations phase, the period between the completion of commissioning and the start of decommissioning

The role of human performance in the safety complex plants' operation

International Nuclear Information System (INIS)

Preda, Irina Aida; Lazar, Roxana Elena; Croitoru, Cornelia

1999-01-01

According to statistics, about 20-30% from the failures occurred in the plants are caused directly or indirectly by human errors. Furthermore, it was established that 10-15% of the global failures are related with the human errors. These are mainly due to the wrong actions, maintenance errors, and misinterpretation of instruments. The human performance is influenced by: professional ability, complexity and danger to the plant experience in the working place, level of skills, events in personal and/or professional life, discipline, social ambience, somatic health. The human performances' assessment in the probabilistic safety assessment offers the possibility of evaluation of human contribution to the events sequences outcome. Not all the human errors have impact on the system. A human error may be recovered before the unwanted consequences had been occurred on system. This paper presents the possibilities to use the probabilistic method (event tree, fault tree) to identify the solutions for human reliability improved in order to minimize the risk in industrial plants' operation. Also, the human error types and their causes are defined and the 'decision tree method' as technique in our analysis for human reliability assessment is presented. The exemplification of human error analysis method was achieved based on operation data for Valcea Heavy Water Pilot Plant. As initiating event for the accident state 'the steam supply interruption' event has been considered. The human errors' contribution was analysed for the accident sequence with the worst consequences. (authors)

Operator psychological selection system for nuclear power plant

International Nuclear Information System (INIS)

He Xuhong; Huang Xiangrui

2004-01-01

Based on a detailed job analysis of nuclear power plant operator including operation procedures analysis, interview with personnel familiar with operator job, and 9 events happened in the past in the plant involved operator error analysis, several operator work characteristics and performance influence factors are obtained. According to these specific characteristics and factors, referring to the psychological selection research results in the other related critical occupational fields, a full psychological selection system of nuclear power plant operator is forwarded in this paper, including 21 dimensions in 3 facets as general psychological ability, personality and psychological healthy. Practical measurement methods for the proposed selection dimensions are discussed in the end

An analysis of nuclear power plant operating costs

International Nuclear Information System (INIS)

1988-01-01

This report presents the results of a statistical analysis of nonfuel operating costs for nuclear power plants. Most studies of the economic costs of nuclear power have focused on the rapid escalation in the cost of constructing a nuclear power plant. The present analysis found that there has also been substantial escalation in real (inflation-adjusted) nonfuel operating costs. It is important to determine the factors contributing to the escalation in operating costs, not only to understand what has occurred but also to gain insights about future trends in operating costs. There are two types of nonfuel operating costs. The first is routine operating and maintenance expenditures (O and M costs), and the second is large postoperational capital expenditures, or what is typically called ''capital additions.'' O and M costs consist mainly of expenditures on labor, and according to one recently completed study, the majoriy of employees at a nuclear power plant perform maintenance activities. It is generally thought that capital additions costs consist of large maintenance expenditures needed to keep the plants operational, and to make plant modifications (backfits) required by the Nuclear Regulatory Commission (NRC). Many discussions of nuclear power plant operating costs have not considered these capital additions costs, and a major finding of the present study is that these costs are substantial. The objective of this study was to determine why nonfuel operating costs have increased over the past decade. The statistical analysis examined a number of factors that have influenced the escalation in real nonfuel operating costs and these are discussed in this report. 4 figs, 19 tabs

Induced simplified neutrosophic correlated aggregation operators for multi-criteria group decision-making

Science.gov (United States)

Şahin, Rıdvan; Zhang, Hong-yu

2018-03-01

Induced Choquet integral is a powerful tool to deal with imprecise or uncertain nature. This study proposes a combination process of the induced Choquet integral and neutrosophic information. We first give the operational properties of simplified neutrosophic numbers (SNNs). Then, we develop some new information aggregation operators, including an induced simplified neutrosophic correlated averaging (I-SNCA) operator and an induced simplified neutrosophic correlated geometric (I-SNCG) operator. These operators not only consider the importance of elements or their ordered positions, but also take into account the interactions phenomena among decision criteria or their ordered positions under multiple decision-makers. Moreover, we present a detailed analysis of I-SNCA and I-SNCG operators, including the properties of idempotency, commutativity and monotonicity, and study the relationships among the proposed operators and existing simplified neutrosophic aggregation operators. In order to handle the multi-criteria group decision-making (MCGDM) situations where the weights of criteria and decision-makers usually correlative and the criterion values are considered as SNNs, an approach is established based on I-SNCA operator. Finally, a numerical example is presented to demonstrate the proposed approach and to verify its effectiveness and practicality.

A computational model for evaluating the effects of attention, memory, and mental models on situation assessment of nuclear power plant operators

International Nuclear Information System (INIS)

Lee, Hyun-Chul; Seong, Poong-Hyun

2009-01-01

Operators in nuclear power plants have to acquire information from human system interfaces (HSIs) and the environment in order to create, update, and confirm their understanding of a plant state, as failures of situation assessment may cause wrong decisions for process control and finally errors of commission in nuclear power plants. A few computational models that can be used to predict and quantify the situation awareness of operators have been suggested. However, these models do not sufficiently consider human characteristics for nuclear power plant operators. In this paper, we propose a computational model for situation assessment of nuclear power plant operators using a Bayesian network. This model incorporates human factors significantly affecting operators' situation assessment, such as attention, working memory decay, and mental model. As this proposed model provides quantitative results of situation assessment and diagnostic performance, we expect that this model can be used in the design and evaluation of human system interfaces as well as the prediction of situation awareness errors in the human reliability analysis.

A computational model for evaluating the effects of attention, memory, and mental models on situation assessment of nuclear power plant operators

Energy Technology Data Exchange (ETDEWEB)

Lee, Hyun-Chul [Instrumentation and Control/Human Factors Division, Korea Atomic Energy Research Institute, 1045 Daedeok-daero, Yuseong-gu, Daejeon 305-353 (Korea, Republic of)], E-mail: leehc@kaeri.re.kr; Seong, Poong-Hyun [Department of Nuclear and Quantum Engineering, Korea Advanced Institute of Science and Technology, 373-1, Guseong-dong, Yuseong-gu, Daejeon 305-701 (Korea, Republic of)

2009-11-15

Operators in nuclear power plants have to acquire information from human system interfaces (HSIs) and the environment in order to create, update, and confirm their understanding of a plant state, as failures of situation assessment may cause wrong decisions for process control and finally errors of commission in nuclear power plants. A few computational models that can be used to predict and quantify the situation awareness of operators have been suggested. However, these models do not sufficiently consider human characteristics for nuclear power plant operators. In this paper, we propose a computational model for situation assessment of nuclear power plant operators using a Bayesian network. This model incorporates human factors significantly affecting operators' situation assessment, such as attention, working memory decay, and mental model. As this proposed model provides quantitative results of situation assessment and diagnostic performance, we expect that this model can be used in the design and evaluation of human system interfaces as well as the prediction of situation awareness errors in the human reliability analysis.

Operating experience review for the AP1000 plant

International Nuclear Information System (INIS)

Chaney, T. E.; Lipner, M. H.

2006-01-01

Westinghouse is performing an update to the Operating Experience Review (OER) Report for the AP1000 project to account for operating experience since December 1996. Significant Operating Experience Reports, Significant Event Reports, Significant Event Notifications, Operations and Maintenance Reminders, Topical Reports, Event Analysis Reports and Licensee Event Reports were researched for pertinent input to the update. As a part of the OER, Westinghouse has also conducted operator interviews and observations during simulated plant operations and after operating events. The main purpose of the OER is to identify Human Factors Engineering (HFE) related safety issues from existing operating plant experience and to ensure that these issues are addressed in the new design. The issues and lessons learned regarding operating experience provide a basis for improving the plant design. (authors)

Optimization of advanced plants operation: The Escrime project

International Nuclear Information System (INIS)

Fiche, C.; Papin, B.

1994-01-01

The Escrime program aims at defining the optimal share of tasks between humans and computers under normal or accidental plant operation. Basic principles we keep in mind are the following: human operators are likely to be necessary in the operation of future plants because we cannot demonstrate that plant design is error free, so unexpected situation can still happen; automation must not release the operators from their decisional role but only help them avoiding situations of cognitive overload which can lead to increase the risk of errors; the optimum share of tasks between human and automatic systems must be based on a critical analysis of the tasks and of the way they are handled. The last point appeared to be of major importance. The corresponding analysis of the French PWR's operating procedures enabled us to define a unified scheme for plant operation under the form of a hierarchy of goals and means. Beyond this analysis, development of a specific testing facility is under way to check the relevance of the proposed plant operation organization and to test the human-machine cooperation in different situations for various levels of automation. 7 refs, 4 figs

THORP and after - challenging state decisions

International Nuclear Information System (INIS)

Bowden, P.; Lawrence, J.

1994-01-01

This article looks at an increasing trend for European Community law to be used by those seeking to challenge decisions taken at a national level which effect the environment. The debate over the future operation of British Nuclear Fuels Ltd's Thermal Oxide Reprocessing Plant at the Sellafield site (THORP) is used as an example of this trend. The United Kingdom government's energy policy authorised the construction and operation of the THORP plant. The decision to continue with the project has been challenged by Greenpeace and Lancashire County Council acting cooperatively. Their challenge was based on Community law and legislation. (UK)

Taxonomy of the nuclear plant operator's role

International Nuclear Information System (INIS)

Kisner, R.A.; Fullerton, A.M.; Frey, P.R.; Dougherty, E.M.

1981-01-01

A program is presently under way at the Oak Ridge National Laboratory (ORNL) to define the functional design requirements of operational aids for nuclear power plant operators. A first and important step in defining these requirements is to develop an understanding of the operator's role or function. This paper describes a taxonomy of operator functions that applies during all operational modes and conditions of the plant. Other topics such as the influence of automation, role acceptance, and the operator's role during emergencies are also discussed. This systematic approach has revealed several areas which have potential for improving the operator's ability to perform his role

Development of Megawatt Demand Setter for Plant Operating Flexibility

International Nuclear Information System (INIS)

Kim, Se Chang; Hah, Yeong Joon; Song, In Ho; Lee, Myeong Hun; Chang, Do Ik; Choi, Jung In

1993-05-01

The Conceptual design of the Megawatt Demand Setter (MDS) is presented for the Korean Standardized Nuclear Power Plant. The MDS is a digital supervisory limitation system. The MDS assures that the plant does not exceed the operating limits by regulating the plant operations through monitoring the operating margins of the critical parameters. MDS is aimed at increasing the operating flexibility which allow the nuclear plant to meet the grid demand in very efficient manner. It responds to the grid demand without penalizing plant availability by limiting the load demand when the operating limits are approached or violated. MDS design concepts were tested using simulation responses of Yonggwang Units 3, 4. The design of the Yonggwang Units 3, 4 would be used as a reference which designs of Korean Standardized Nuclear Power Plants would be based upon. The simulation results illustrate that the MDS can be used to improve operating flexibility. (Author)

The assisting system for uranium enrichment plant operation

International Nuclear Information System (INIS)

Nakazawa, Hiroaki; Yamamoto, Fumio

1990-01-01

We have been developing an operation assisting system, partially supported by AI system, for uranium enrichment plant. The AI system is a proto-type system aiming a final one which can be applied to any future large uranium enrichment plant and also not only to specific operational area but also to complex and multi-phenomenon operational area. An existing AI system, for example facility diagnostic system that utilizes the result of CCT analysis as knowledge base, has weakness in flexibility and potentiality. To build AI system, we have developed the most suitable knowledge representations using deep knowledge for each facility or operation of uranium enrichment plant. This paper describes our AI proto-type system adopting several knowledge representations that can represent an uranium enrichment plant's operation with deep knowledge. (author)

Location Decisions of U.S. Polluting Plants. Theory, Empirical Evidence, and Consequences

International Nuclear Information System (INIS)

Shadbegian, R.; Wolverton, A.

2010-01-01

Economists have long been interested in explaining the spatial distribution of economic activity, focusing on what factors motivate profit-maximizing firms when they choose to open a new plant or expand an existing facility. We begin our paper with a general discussion of the theory of plant location, including the role of taxes and agglomeration economies. However, our paper focuses on the theory, evidence, and implications of the role of environmental regulations in plant location decisions. On its face, environmental regulation would not necessarily be expected to alter location decisions, since we would expect Federal regulation to affect all locations in the United States essentially equally. It turns out, however, that this is not always the case as some geographic areas are subject to greater stringency. Another source of variation is differences across states in the way they implement and enforce compliance with Federal regulation. In light of these spatial differences in the costs of complying with environmental regulations, we discuss three main questions in this survey: Do environmental regulations affect the location decisions of polluting plants? Do states compete for polluting plants through differences in environmental regulation? And, do firms locate polluting plants disproportionately near poor and minority neighborhoods?.

Location Decisions of U.S. Polluting Plants. Theory, Empirical Evidence, and Consequences

Energy Technology Data Exchange (ETDEWEB)

Shadbegian, R.; Wolverton, A.

2010-06-15

Economists have long been interested in explaining the spatial distribution of economic activity, focusing on what factors motivate profit-maximizing firms when they choose to open a new plant or expand an existing facility. We begin our paper with a general discussion of the theory of plant location, including the role of taxes and agglomeration economies. However, our paper focuses on the theory, evidence, and implications of the role of environmental regulations in plant location decisions. On its face, environmental regulation would not necessarily be expected to alter location decisions, since we would expect Federal regulation to affect all locations in the United States essentially equally. It turns out, however, that this is not always the case as some geographic areas are subject to greater stringency. Another source of variation is differences across states in the way they implement and enforce compliance with Federal regulation. In light of these spatial differences in the costs of complying with environmental regulations, we discuss three main questions in this survey: Do environmental regulations affect the location decisions of polluting plants? Do states compete for polluting plants through differences in environmental regulation? And, do firms locate polluting plants disproportionately near poor and minority neighborhoods?.

Maintenance planning support method for nuclear power plants based on collective decision making

International Nuclear Information System (INIS)

Shimizu, Shunichi; Sakurai, Shoji; Takaoka, Kazushi; Kanemoto, Shigeru; Fukutomi, Shigeki

1992-01-01

Inspection and maintenance planning in nuclear power plants is conducted by decision making based on experts' collective consensus. However, since a great deal of time and effort is required to reach a consensus among expert judgments, the establishment of effective decision making methods is necessary. Therefore, the authors developed a method for supporting collective decision making, based on a combination of three types of decision making methods; the Characteristic Diagram method, Interpretative Structural Modeling method, and the Analytic Hierarchy Process method. The proposed method enables us to determine the evaluation criteria systematically for collective decision making, and also allows extracting collective decisions using simplified questionnaires. The proposed method can support reaching a consensus of groups effectively through the evaluation of collective decision structural models and their characteristics. In this paper, the effectiveness of the proposed method was demonstrated through its application to the decision making problem concerning whether or not the improved ultrasonic testing equipment should be adopted at nuclear power plants. (author)

Review of operating history at the Palisades Nuclear Plant

International Nuclear Information System (INIS)

Mays, G.T.; Harrington, K.H.

1982-01-01

the Systematic Evaluation Program Branch (SEPB) of the Nuclear Regulatory Commission (NRC) is conducting the Systematic Evaluation Program whose purpose is to determine the safety margins of the design and operation of the eleven oldest operating commercial nuclear power plants in the United States. A portion of the SEP includes the compilation and interpretation of operational occurrences at these plants. This summary describes the methodology and results of the operational experience review of Palisades Nuclear Plant. The review includes a detailed examination of the operating experience in two segments - plant shutdowns and power reductions, and reportable events

Safety of Nuclear Power Plants: Commissioning and Operation

International Nuclear Information System (INIS)

2011-01-01

The safety of a nuclear power plant is ensured by means of proper site selection, design, construction and commissioning, and the evaluation of these, followed by proper management, operation and maintenance of the plant. In a later phase, a proper transition to decommissioning is required. The organization and management of plant operations ensures that a high level of safety is achieved through the effective management and control of operational activities. This publication is a revision of the Safety Requirements publication Safety of Nuclear Power Plants: Operation, which was issued in 2000 as IAEA Safety Standards Series No. NS-R-2. The purpose of this revision was to restructure Safety Standards Series No. NS-R-2 in the light of new operating experience and new trends in the nuclear industry; to introduce new requirements that were not included in Safety Standards Series No. NS-R-2 on the operation of nuclear power plants; and to reflect current practices, new concepts and technical developments. This update also reflects feedback on the use of the standards, both from Member States and from the IAEA's safety related activities. The publication is presented in the new format for Safety Requirements publications. The present publication reflects the safety principles of the Fundamental Safety Principles. It has been harmonized with IAEA Safety Standards Series No. GS-R-3 on The Management System for Facilities and Activities. Guidance on the fulfilment of the safety requirements is provided in supporting Safety Guides. The terminology used in this publication is defined and explained in the IAEA Safety Glossary. The objective of this publication is to establish the requirements which, in the light of experience and the present state of technology, must be satisfied to ensure the safe operation of nuclear power plants. These requirements are governed by the safety objective and safety principles that are established in the Fundamental Safety Principles. This

Engineerig of structural modifications for operating nuclear plants

International Nuclear Information System (INIS)

Duffy, T.J.; Gazda, P.A.

1983-01-01

The engineering of structural modifications for operating nuclear plants offers many challenges in the areas of scheduling of work, field adjustments, and engineering staff planning. The scheduling of structural modification work for operating nuclear plants is normally closely tied to planned or unplanned outages of the plant. Coordination between the structural engineering effort, the operating plant staff, and the contractor who will be performing the modifications is essential to ensure that all work can be completed within the allotted time. Due to the inaccessibility of areas in operating plants or the short time available to perform the structural engineering in the case of an unscheduled outage, field verification of a design is not always possible prior to initiating the construction of the modification. This requires the structural engineer to work closely with the contractor to promptly resolve problems due to unanticipated interferences or material procurement that may arise during the course of construction. The engineering staff planning for structural modifications at an operating nuclear plant must be flexible enough to permit rapid response to the common 'fire drills', but controlled enough to assure technically correct designs and minimize the expenditure of man-hours and resulting engineering cost. (orig.)

Engineering development of a digital replacement protection system at an operating US PWR nuclear power plant: Installation and operational experiences

International Nuclear Information System (INIS)

Miller, M.H.

1995-01-01

The existing Reactor Protection Systems (RPSs) at most US PWRs are systems which reflect 25 to 30 year-old designs, components and manufacturing techniques. Technological improvements, especially in relation to modern digital systems, offer improvements in functionality, performance, and reliability, as well as reductions in maintenance and operational burden. The Nuclear power industry and the US nuclear regulators are poised to move forward with the issues that have slowed the transition to modern digital replacements for nuclear power plant safety systems. The electric utility industry is now more than ever being driven by cost versus benefit decisions. Properly designed, engineered, and installed digital systems can provide adequate cost-benefit and allow continued nuclear generated electricity. This paper describes various issues and areas related to an ongoing RPS replacement demonstration project which are pertinant for a typical US nuclear plant to consider cost-effective replacement of an aging analog RPS with a modern digital RPS. The following subject areas relative to the Oconee Nuclear Station ISAT trademark Demonstrator project are discussed: Operator Interface Development; Equipment Qualification; Validation and Verification of Software; Factory Testing; Field Changes and Verification Testing; Utility Operational, Engineering and Maintenance; Experiences with Demonstration System; and Ability to operate in parallel with the existing Analog RPS

Engineering development of a digital replacement protection system at an operating US PWR nuclear power plant: Installation and operational experiences

Energy Technology Data Exchange (ETDEWEB)

Miller, M.H. [Duke Power Co., Seneca, SC (United States)

1995-04-01

The existing Reactor Protection Systems (RPSs) at most US PWRs are systems which reflect 25 to 30 year-old designs, components and manufacturing techniques. Technological improvements, especially in relation to modern digital systems, offer improvements in functionality, performance, and reliability, as well as reductions in maintenance and operational burden. The Nuclear power industry and the US nuclear regulators are poised to move forward with the issues that have slowed the transition to modern digital replacements for nuclear power plant safety systems. The electric utility industry is now more than ever being driven by cost versus benefit decisions. Properly designed, engineered, and installed digital systems can provide adequate cost-benefit and allow continued nuclear generated electricity. This paper describes various issues and areas related to an ongoing RPS replacement demonstration project which are pertinant for a typical US nuclear plant to consider cost-effective replacement of an aging analog RPS with a modern digital RPS. The following subject areas relative to the Oconee Nuclear Station ISAT{trademark} Demonstrator project are discussed: Operator Interface Development; Equipment Qualification; Validation and Verification of Software; Factory Testing; Field Changes and Verification Testing; Utility Operational, Engineering and Maintenance; Experiences with Demonstration System; and Ability to operate in parallel with the existing Analog RPS.

How sulphur was dislodged to sustain plant operation

International Nuclear Information System (INIS)

Verma, A.N.; Agarwal, A.K.

1997-01-01

Heavy Water Plant (Kota) employs chemical exchange between water and hydrogen sulphide gas. Formation of sulphur is a known phenomena during production of heavy water in G.S. process plants. It is observed that after three years of plant operation this sulphur is enough to choke the cold tower trays causing flooding of exchange towers and resultant decrease in throughput. G.S. process plants normally go for major turn around once in four years when sulphur is either manually cleaned or removed by steam wash after hydrogen sulphide gas has been removed from the system and towers have been fully decontaminated. As throughput starts decreasing after third year and plant operation becomes more difficult in fourth year, HWP (Kota) had evolved a procedure of heating the towers for dislodging sulphur from sieve trays when plant is running. With these procedures plant operation could be sustained without tower floodings even in fourth year, before plant could go for major turn around for manual removal of sulphur

Nuclear power plant operation experience - a feedback programme

International Nuclear Information System (INIS)

Banica, I.; Sociu, F.; Margaritescu, C.

1994-01-01

An effective high quality maintenance programme is required for the safe reliable operation of a nuclear power plant. To achieve the objectives of such a programme, both plant management and staff must be highly dedicated and motivated to perform high quality work at all levels. Operating and maintenance experience data collections and analysis are necessary in order to enhance the safety of the plant and reliability of the structures systems and components throughout their operating life. Significant events, but also minor incident, may reveal important deficiencies or negative trends adverse to safety. Therefore, a computer processing system for collecting, classifying and evaluating abnormal events or findings concerning operating-maintenance and for feeding back the results of the lessons learned from experience into the design and the operation of our nuclear power plant is considered to be of paramount importance. (Author)

On the plant operators performance during earthquake

International Nuclear Information System (INIS)

Kitada, Y.; Yoshimura, S.; Abe, M.; Niwa, H.; Yoneda, T.; Matsunaga, M.; Suzuki, T.

1994-01-01

There is little data on which to judge the performance of plant operators during and after strong earthquakes. In order to obtain such data to enhance the reliability on the plant operation, a Japanese utility and a power plant manufacturer carried out a vibration test using a shaking table. The purpose of the test was to investigate operator performance, i.e., the quickness and correctness in switch handling and panel meter read-out. The movement of chairs during earthquake as also of interest, because if the chairs moved significantly or turned over during a strong earthquake, some arresting mechanism would be required for the chair. Although there were differences between the simulated earthquake motions used and actual earthquakes mainly due to the specifications of the shaking table, the earthquake motions had almost no influence on the operators of their capability (performance) for operating the simulated console and the personal computers

Operator training simulator for BWR nuclear power plant

International Nuclear Information System (INIS)

Watanabe, Tadasu

1988-01-01

For the operation management of nuclear power stations with high reliability and safety, the role played by operators is very important. The effort of improving the man-machine interface in the central control rooms of nuclear power stations is energetically advanced, but the importance of the role of operators does not change. For the training of the operators of nuclear power stations, simulators have been used from the early stage. As the simulator facilities for operator training, there are the full scope simulator simulating faithfully the central control room of an actual plant and the small simulator mainly aiming at learning the plant functions. For BWR nuclear power stations, two full scope simulators are installed in the BWR Operator Training Center, and the training has been carried out since 1974. The plant function learning simulators have been installed in respective electric power companies as the education and training facilities in the companies. The role of simulators in operator training, the BTC No.1 simulator of a BWR-4 of 780 MWe and the BTC No.2 simulator of a BWR-5 of 1,100 MWe, plant function learning simulators, and the design of the BTC No.2 simulator and plant function learning simulators are reported. (K.I.)

Computerized heat balance models to predict performance of operating nuclear power plants

International Nuclear Information System (INIS)

Breeding, C.L.; Carter, J.C.; Schaefer, R.C.

1983-01-01

The use of computerized heat balance models has greatly enhanced the decision making ability of TVA's Division of Nuclear Power. These models are utilized to predict the effects of various operating modes and to analyze changes in plant performance resulting from turbine cycle equipment modifications with greater speed and accuracy than was possible before. Computer models have been successfully used to optimize plant output by predicting the effects of abnormal condenser circulating water conditions. They were utilized to predict the degradation in performance resulting from installation of a baffle plate assembly to replace damaged low-pressure blading, thereby providing timely information allowing an optimal economic judgement as to when to replace the blading. Future use will be for routine performance test analysis. This paper presents the benefits of utility use of computerized heat balance models

Exponential operations and aggregation operators of interval neutrosophic sets and their decision making methods.

Science.gov (United States)

Ye, Jun

2016-01-01

An interval neutrosophic set (INS) is a subclass of a neutrosophic set and a generalization of an interval-valued intuitionistic fuzzy set, and then the characteristics of INS are independently described by the interval numbers of its truth-membership, indeterminacy-membership, and falsity-membership degrees. However, the exponential parameters (weights) of all the existing exponential operational laws of INSs and the corresponding exponential aggregation operators are crisp values in interval neutrosophic decision making problems. As a supplement, this paper firstly introduces new exponential operational laws of INSs, where the bases are crisp values or interval numbers and the exponents are interval neutrosophic numbers (INNs), which are basic elements in INSs. Then, we propose an interval neutrosophic weighted exponential aggregation (INWEA) operator and a dual interval neutrosophic weighted exponential aggregation (DINWEA) operator based on these exponential operational laws and introduce comparative methods based on cosine measure functions for INNs and dual INNs. Further, we develop decision-making methods based on the INWEA and DINWEA operators. Finally, a practical example on the selecting problem of global suppliers is provided to illustrate the applicability and rationality of the proposed methods.

Modeling operator actions during a small break loss-of-coolant accident in a Babcock and Wilcox nuclear power plant

International Nuclear Information System (INIS)

Ghan, L.S.; Ortiz, M.G.

1991-01-01

A small break loss-of-accident (SBLOCA) in a typical Babcock and Wilcox (B ampersand W) nuclear power plant was modeled using RELAP5/MOD3. This work was performed as part of the United States Regulatory Commission's (USNRC) Code, Scaling, Applicability and Uncertainty (CSAU) study. The break was initiated by severing one high pressure injection (HPI) line at the cold leg. Thus, the small break was further aggravated by reduced HPI flow. Comparisons between scoping runs with minimal operator action, and full operator action, clearly showed that the operator plays a key role in recovering the plant. Operator actions were modeled based on the emergency operating procedures (EOPs) and the Technical Bases Document for the EOPs. The sequence of operator actions modeled here is only one of several possibilities. Different sequences of operator actions are possible for a given accident because of the subjective decisions the operator must make when determining the status of the plant, hence, which branch of the EOP to follow. To assess the credibility of the modeled operator actions, these actions and results of the simulated accident scenario were presented to operator examiners who are familiar with B ampersand W nuclear power plants. They agreed that, in general, the modeled operator actions conform to the requirements set forth in the EOPs and are therefore plausible. This paper presents the method for modeling the operator actions and discusses the simulated accident scenario from the viewpoint of operator actions

Efficient use of measurement data guarantees correct decisions

Energy Technology Data Exchange (ETDEWEB)

Ruokonen, T.; Kurki, H. [ed.

1997-11-01

The dizzying pace at which information technology has developed has had a considerable effect on the operation and maintenance of power plants as well. Modern power plants have been automated to a great extent, and a large number of information systems assist operating staff in daily decision-making

Transparency and efficiency through plant operations management systems

International Nuclear Information System (INIS)

Ladage, L.

2001-01-01

Plant operations management systems, being IT application systems, provide integral support of the business processes making up plant operations management. The use of plant operations management systems improves mutually interdependent factors, such as high economic performance, high availability, and maximum safety. Since its commissioning in 1988, the Emsland nuclear power station (KKE) has been run with the IBFS plant operations management system. The work flow management system (WfMS), a module of IBFS, is described as an example of job order processing. IBFS-WfMS is to optimize all processes, thus cutting costs and ensuring that processes are run and documented reliably. Assessing the savings effect achieved through the use of IBFS-WfMS clearly reveals the savings in work/time achieved by the system. These savings are quoted as approx. 4 minutes and DM 10, respectively, per working step, which corresponds to several dozens of manyears or several million DM per annum in the KKE plant under consideration. This result can be extrapolated to other plants. (orig.) [de

The control of operational risk in nuclear power plant operations - Some cross-cultural perspectives

International Nuclear Information System (INIS)

Suchard, A.; Rochlin, G.

1992-01-01

The operation of nuclear power plants requires the management of a complex technology under exacting performance and safety criteria. Organizations operating nuclear power plants are faced with the challenge of simultaneously meeting technical, organizational, and social demands, striving toward perfection in a situation where learning by trial and error can be too costly. In this process, they interact with regulatory bodies who seek to help minimize operational risk by imposing and upholding safety standards. The character of this interaction differs in various countries, as does the larger cultural setting. The study generally pursued the question of how organizations operating complex and demanding technologies adapt to such requirements and circumstances, and how they can succeed in delivering nearly error-free performance. One aspect of this study includes the comparison of organizational and cultural environments for nuclear power plant operations in the US, France, Germany, Sweden, and Switzerland. The research involved in-depth, continuous observations on location and interviews with plant personnel, especially control operators, at one plant in each country

Nuclear power plant operating experience. Annual report, 1978

International Nuclear Information System (INIS)

Beebe, M.R.

1979-12-01

This report is the fifth in a series of reports issued annually that summarizes the operating experience of US nuclear power plants in commercial operation. Power generation statistics, plant outages, reportable occurrences, fuel element performance, occupational radiation exposure for each plant are presented. Summary highlights of these areas are discussed. The report includes 1978 data from 65 plants - 25 boiling water reactor plants and 40 pressurized water reactor plants. Discussion of radioactive effluents which has been a part of this report in previous years, has not been included in this issue because of late acquisition of data

Improved core monitoring for improved plant operations

International Nuclear Information System (INIS)

Mueller, N.P.

1987-01-01

Westinghouse has recently installed a core on-line surveillance, monitoring and operations systems (COSMOS), which uses only currently available core and plant data to accurately reconstruct the core average axial and radial power distributions. This information is provided to the operator in an immediately usable, human-engineered format and is accumulated for use in application programs that provide improved core performance predictive tools and a data base for improved fuel management. Dynamic on-line real-time axial and radial core monitoring supports a variety of plant operations to provide a favorable cost/benefit ratio for such a system. Benefits include: (1) relaxation or elimination of certain technical specifications to reduce surveillance and reporting requirements and allow higher availability factors, (2) improved information displays, predictive tools, and control strategies to support more efficient core control and reduce effluent production, and (3) expanded burnup data base for improved fuel management. Such systems can be backfit into operating plants without changing the existing instrumentation and control system and can frequently be implemented on existing plant computer capacity

Decision Support System for Reservoir Management and Operation in Africa

Science.gov (United States)

Navar, D. A.

2016-12-01

Africa is currently experiencing a surge in dam construction for flood control, water supply and hydropower production, but ineffective reservoir management has caused problems in the region, such as water shortages, flooding and loss of potential hydropower generation. Our research aims to remedy ineffective reservoir management by developing a novel Decision Support System(DSS) to equip water managers with a technical planning tool based on the state of the art in hydrological sciences. The DSS incorporates a climate forecast model, a hydraulic model of the watershed, and an optimization model to effectively plan for the operation of a system of cascade large-scale reservoirs for hydropower production, while treating water supply and flood control as constraints. Our team will use the newly constructed hydropower plants in the Omo Gibe basin of Ethiopia as the test case. Using the basic HIDROTERM software developed in Brazil, the General Algebraic Modeling System (GAMS) utilizes a combination of linear programing (LP) and non-linear programming (NLP) in conjunction with real time hydrologic and energy demand data to optimize the monthly and daily operations of the reservoir system. We compare the DSS model results with the current reservoir operating policy used by the water managers of that region. We also hope the DSS will eliminate the current dangers associated with the mismanagement of large scale water resources projects in Africa.

A Hybrid Multiple-Criteria Decision-Making Approach for Photovoltaic Solar Plant Location Selection

Directory of Open Access Journals (Sweden)

Amy H. I. Lee

2017-01-01

Full Text Available Due to decaying fossil resource and increasing environmental consciousness, the demand of renewable energy resources is escalating these days. Photovoltaic solar energy is one of the most popular renewable energy resources in places where sunlight is abundant. The selection of a desirable location for constructing a photovoltaic solar plant is the first and one of the most important stages in the plant construction to provide a long-term energy production. In this paper, a comprehensive multiple-criteria decision-making model, which incorporates the interpretive structural modeling (ISM, fuzzy analytic network process (FANP and VIKOR (VlseKriterijumska OptimizacijaI Kompromisno Resenje in Serbian,meaning multi-criteria optimization and compromise solution, is proposed to select the most suitable photovoltaic solar plant location. The ISM is applied first to determine the interrelationships among the criteria and among the sub-criteria,andtheresults are used to construct a decision-making network. The FANP is applied next to solve the network and to calculate the importance weights of the sub-criteria. Finally, the VIKOR is adopted to determine the ranking of the photovoltaic solar plant locations. The proposed model is applied in a case study in evaluating photovoltaic solar plant locations in Taiwan. By applying the proposed model, decision makers can have a better thinking process and make more appropriate decisions justifiably.

Decision-Making: Are Plants More Rational than Animals?

Science.gov (United States)

Schmid, Bernhard

2016-07-25

A new study presents a novel experimental design and allows a test of risk sensitivity in plants. Faced with a choice between constant and variable resource supply, they make a rational decision for the option that maximizes fitness, a fact rarely observed in animals. Copyright © 2016 Elsevier Ltd. All rights reserved.

The prioritisation of invasive alien plant control projects using a multi-criteria decision model informed by stakeholder input and spatial data.

Science.gov (United States)

Forsyth, G G; Le Maitre, D C; O'Farrell, P J; van Wilgen, B W

2012-07-30

Invasions by alien plants are a significant threat to the biodiversity and functioning of ecosystems and the services they provide. The South African Working for Water program was established to address this problem. It needs to formulate objective and transparent priorities for clearing in the face of multiple and sometimes conflicting demands. This study used the analytic hierarchy process (a multi-criteria decision support technique) to develop and rank criteria for prioritising alien plant control operations in the Western Cape, South Africa. Stakeholder workshops were held to identify a goal and criteria and to conduct pair-wise comparisons to weight the criteria with respect to invasive alien plant control. The combination of stakeholder input (to develop decision models) with data-driven model solutions enabled us to include many alternatives (water catchments), that would otherwise not have been feasible. The most important criteria included the capacity to maintain gains made through control operations, the potential to enhance water resources and conserve biodiversity, and threats from priority invasive alien plant species. We selected spatial datasets and used them to generate weights that could be used to objectively compare alternatives with respect to agreed criteria. The analysis showed that there are many high priority catchments which are not receiving any funding and low priority catchments which are receiving substantial allocations. Clearly, there is a need for realigning priorities, including directing sufficient funds to the highest priority catchments to provide effective control. This approach provided a tractable, consensus-based solution that can be used to direct clearing operations. Copyright © 2012 Elsevier Ltd. All rights reserved.

Operation of nuclear power plants

International Nuclear Information System (INIS)

Severa, P.

1988-04-01

The textbook for training nuclear power plant personnel is centred on the most important aspects of operating modes of WWER-440 reactors. Attention is devoted to the steady state operation of the unit, shutdown, overhaul with refuelling, physical and power start-up. Also given are the regulations of shift operation and the duties of individual categories of personnel during the shift and during the change of shifts. (Z.M.). 3 figs., 1 tab

Improvment, extension and integration of operational decision support systems for nuclear emergency management (DSSNET)

International Nuclear Information System (INIS)

Ehrhardt, J.

2005-07-01

The DSSNET network was established in October 2000 with the overall objective to create an effective and accepted framework for better communication and understanding between the community of institutions involved in operational off-site emergency management and the many and diverse RTD institutes further developing methods and tools in this area, in particular decision support systems (DSS), for making well informed and consistent judgements with respect to practical improvements of emergency response in Europe. 37 institutions from 21 countries of East and West Europe have been members of the network with about half of them responsible for operational emergency management. The objectives of the network have been numerous and the more important ones include: to ensure that future RTD is more responsive to user needs, to inform the user community of new developments and their potential for improving emergency response, to improve operational decision support systems from feedback of operational experience, to identify how information and data exchange between countries can be improved, to promote greater coherence among operational decision support systems and to encourage shared development of new and improved decision support systems features, and to improve the practicability of operational decision support systems. To stimulate the communication and feedback between the operational and the RTD community, problem-oriented emergency exercises were performed, which covered the various time phases of an accident and which extended from the near range to farther distances with frontier crossing transport of radionuclides. The report describes the objectives of the DSSNET, the five emergency exercises performed and the results of their evaluation. They provided valuable insight and lessons for operators and users of decision support systems, in particular the need for much more intensive training and exercising with decision support systems and their interaction with

Technology of turbine plant operating with wet steam

International Nuclear Information System (INIS)

1989-01-01

The technology of turbine plant operating with wet steam is a subject of continuing interest and importance, notably in view of the widespread use of wet steam cycles in nuclear power plants and the recent developments of advanced low pressure blading for both conventional and wet steam turbines. The nature of water formation in expanding steam has an important influence on the efficiency of turbine blading and on the integrity and safe operating life of blading and associated turbine and plant components. The subjects covered in this book include research, flow analysis and measurement, development and design of turbines and ancillary plant, selection of materials of construction, manufacturing methods and operating experience. (author)

A basis for sound management-plant-operator interface

International Nuclear Information System (INIS)

Oak, H.D.

1983-01-01

Sound management-plant-operator interface is based on the application of suitable quality assurance principles. Quality assurance can aptly be termed ''putting priority and emphasis where such are due''. Accordingly, the application of suitable quality assurance principles achieves the all-important combination of both safety and production. Neither of these is mutually exclusive of the other, and both together establish the prime foundation for long-term nuclear power plant operation. This paper presents the application of suitable quality assurance principles to the management, the plant, the operators, and the interface between them. (author)

The critical safety functions and plant operation

International Nuclear Information System (INIS)

Corcoran, W.R.; Church, J.F.; Porter, N.J.; Cross, M.T.; Guinn, W.M.

1981-01-01

The paper outlines the operator's role in nuclear safety and introduces the concept of ''safety functions''. Safety functions are a group of actions that prevent core melt or minimize radiation releases to the general public. They can be used to provide a hierarchy of practical plant protection that an operator should use. ''An accident identical to that at Three Mile Island is not going to happen again'', said the Rogovin investigators. The concepts put forward in this paper are intended to help the operator avoid serious consequence from the next unexpected threat. On the basis of the safety evaluation, the operator has three roles in assuring that the consequences of an event will be no worse than the predicted acceptable results. These three operator roles are: first, maintain plant setup in readiness to properly respond; second, operate the plant in a manner such that fewer, milder events minimize the frequency and the severity of adverse events; third, the operator needs to monitor the plant to verify that the safety functions are accomplished. The operator needs a systematic approach to mitigating the consequences of an event. The concept of ''safety function'' introduces that systematic approach and prevents a hierarchy of protection. If the operator has difficulty in identifying an event for any reason, the systematic safety function approach allows ones to accomplish the overall path of mitigating consequences. There are ten identified functions designed to protect against core melt, preserve containment integrity, prevent indirect release of radioactivity, and maintain vital auxiliaries needed to support the other safety functions. The paper describes in detail the operator's role and the safety functions, and provides many examples of the use of alternative success paths to accomplish the safety function

Institute of nuclear power operations perspectives on PSA applications

International Nuclear Information System (INIS)

Webster, W.E.; Miller, W.J. Jr.

1996-01-01

The investment to develop a PSA is very substantial, and therefore, there is motivation to recover this investment through further use of the techniques used to develop it. It is not surprising that nuclear power plant staff are beginning to use PSA to make operational decisions. The Institute of Nuclear Power Operations is interested in those factors that impact the conduct of plant operations and therefore is actively monitoring the increased usage of PSA techniques. The purpose of this paper is to provide some thoughts and perspectives on the use of PSA as a factor in operational decision making, including decision making in activities performed by engineering, maintenance and operation personnel. (author)

Computer simulation of thermal plant operations

CERN Document Server

O'Kelly, Peter

2012-01-01

This book describes thermal plant simulation, that is, dynamic simulation of plants which produce, exchange and otherwise utilize heat as their working medium. Directed at chemical, mechanical and control engineers involved with operations, control and optimization and operator training, the book gives the mathematical formulation and use of simulation models of the equipment and systems typically found in these industries. The author has adopted a fundamental approach to the subject. The initial chapters provide an overview of simulation concepts and describe a suitable computer environment.

Plant operation monitoring method and device therefor

International Nuclear Information System (INIS)

Ando, Tsugio; Matsuki, Tsutomu.

1997-01-01

The present invention provides a method of and a device for monitoring the operation of a nuclear power plant during operation, which improves the safety and reliability of operation without increasing an operator's burden. Namely, a chief in charge orally instruct an operation to an operator upon the operation of a plant constituent equipment. The operator points the equipment and calls the name. Actual operation instruction for the equipment is inputted after confirmation by oral response. The voices of theses series of operation instruction/point-calling/response confirmation are taken into a voice recognition processing device. The processing device discriminates each of the person who calls, and discriminates the content of the calls and objective equipments to be operated. Then, the series of procedures and contents of the operation for the equipments previously disposed in the data base are compared with the order of inputted calls, discriminated contents and the objective equipments to be operated. If they are not agreed with each other, the operation instruction is blocked even if actual operation instructions are inputted. (I.S.)

Operating experience from Swedish nuclear power plants, 1999

Energy Technology Data Exchange (ETDEWEB)

NONE

2000-07-01

The total generation of electricity from Swedish nuclear power plants was 70.1 TWh during 1999, which is slightly more than the mean value for the last five years. The total electricity consumption decreased by one percent, compared with 1998, to a total of 142.3 TWh, due to an unusually warm summer and autumn. The abundant supply of hydroelectric power resulted in comparatively extensive load-following operation by the nuclear plants during the year. Production losses due to low demand totalled 3.0 TWh. The closure of Barsebaeck 1 will result in a capacity reduction exceeding 4 TWh per year. The hydroelectric power production was 70 TWh, which was 6 TWh more than during a normal year, i.e. a year with average rainfall. The remaining production sources, mainly from solid fuel plants combined with district heating contributed 9 TWh. Electricity generation by means of wind power is still increasing. There are now about 470 wind power stations, which produced 0.3 TWh during the year. The total electricity generation totalled 149.8 TWh, a three percent decrease compared with 1998. The preliminary figures for export were 15.9 TWh and for import 8.4 TWh. The figures above are calculated from the preliminary production result. A comprehensive report on electric power supply and consumption in Sweden is provided in the 1999 Annual Report from the Swedish Power Association. The unit capability factor for the PWRs at Ringhals averaged 91%, while the BWRs averaged 82% mainly due to the extended outages. The BWR reactors at Forsmark averaged as much as 93%. Forsmark 1 experienced the shortest refuelling outage ever in Sweden, only 9 days and 20 hours. In May, Oskarshamn 2 passed a historical milestone - the unit produced 100 TWh since connection to the grid in 1974. The final production day for Barsebaeck 1, which had been in commercial operation since 1975, was on November 30 when a decision by the Swedish Government revoked the operating licence. Three safety-related events

Operation of Finnish nuclear power plants

International Nuclear Information System (INIS)

Tossavainen, K.

1993-06-01

Quarterly reports on the operation of Finnish nuclear power plants describe events and observations, relating to nuclear and radiation safety, which the Finnish Centre for Radiation and Nuclear Safety considers significant. Also other events of general interest are reported. The reports also include a summary of the radiation safety of plant personnel and the environment, as well as tabulated data on the plants' production and load factors

Qualification of nuclear power plant operations personnel

International Nuclear Information System (INIS)

1984-01-01

With the ultimate aim of reducing the possibility of human error in nuclear power plant operations, the Guidebook discusses the organizational aspects, the staffing requirements, the educational systems and qualifications, the competence requirements, the ways to establish, preserve and verify competence, the specific aspects of personnel management and training for nuclear power plant operations, and finally the particular situations and difficulties to be overcome by utilities starting their first nuclear power plant. An important aspect presented in the Guidebook is the experience in training and qualification of nuclear power plant personnel in various countries: Argentina, Belgium, Canada, Czechoslovakia, France, Federal Republic of Germany, Spain, Sweden, United Kingdom and United States of America

Experience in construction and operation of HWR plants in Argentina

International Nuclear Information System (INIS)

Madero, C.C.; Cosentino, J.O.

1982-01-01

''ATUCHA I'', the first nuclear power plant in Argentina, is in commerical operation since 1974 with a high capacity factor. The reactor is based on the MZFR prototype designed by SIEMENS with natural uranium and heavy water and PWR technic. The plant was built by SIEMENS on a turnkey contract and was rated 340 MWe. The offer presented in that opportunity by KWU was based on two reactors (ATUCHA I type) inside one single containment, due to the limitation in power of the reactor. Subsequent changes in the nature of the contract resulted in an active participation of CNEA engineering groups in the erection and commissioning of the reactor. In 1978 the national government approved a nuclear power plan to install four 600 MWe HWR plants until 1995. To start implementing this program, CNEA called for tenders for the supply of components and services for the ATUCHA II plant, in connection with the establishment of a local engineering company and the supply and construction of a heavy water production plant. In 1980 a contract was signed with KWU and the local company ENACE was formed to act as architect engineer and site coordinator. The plant will be located in the ATUCHA I site and the reactor will be similar but double in power to that one. Following the schedule of the nuclear plan, CNEA has just started preliminary studies for the next nuclear plant. ENACE will be responsible for the preparation of an offer for an ATUCHA reactor type. Local engineering and manufacturing firms, upon request and coordination from CNEA, and evaluating the local capacity to participate in the design and construction of a CANDU type nuclear plant. Final decision on this fourth nuclear plant in Argentina will be taken middle 1983. (J.P.N.)

Managing the 'gaps' in a regimen of control - operational decision making in nuclear power

Energy Technology Data Exchange (ETDEWEB)

McDougall, S.J. [Leading Safety Culture Inc., Port Elgin, ON (Canada)

2014-07-01

Nuclear power performance has significantly improved over the last thirty years. This improvement has been based on a philosophy of control. That is, for each issue that must be managed to achieve safe performance, a pre-determined constraint must be established. In addition to the barriers that were designed into the plant, a large range of programs, processes and procedures have been developed to direct the activities of anyone associated with the plant. The premise is that following pre-determined procedures, in a diligent way, will support ongoing plant safety. But what if an issue arises for which there is no procedure? For serious situations, emergency procedures exist to guide operations personnel to place the plant in a safe state. However, the vast majority of issues are much more mundane and form a part of the daily life in the plant. In these cases the nuclear industry has been encouraging the use of an 'Operational Decision Making' (ODM) process. This paper will review ODM as practiced within the context of the governing paradigm of control. The paper will show the strengths of the process and areas for development. ODM is an important tool for managers within the complex socio-technical system that is nuclear power today. This paper summarises key points from a research thesis completed by the author to meet the requirements of an MSc program in 'Human Factors and System Safety'. (author)

Managing the 'gaps' in a regimen of control - operational decision making in nuclear power

International Nuclear Information System (INIS)

McDougall, S.J.

2014-01-01

Nuclear power performance has significantly improved over the last thirty years. This improvement has been based on a philosophy of control. That is, for each issue that must be managed to achieve safe performance, a pre-determined constraint must be established. In addition to the barriers that were designed into the plant, a large range of programs, processes and procedures have been developed to direct the activities of anyone associated with the plant. The premise is that following pre-determined procedures, in a diligent way, will support ongoing plant safety. But what if an issue arises for which there is no procedure? For serious situations, emergency procedures exist to guide operations personnel to place the plant in a safe state. However, the vast majority of issues are much more mundane and form a part of the daily life in the plant. In these cases the nuclear industry has been encouraging the use of an 'Operational Decision Making' (ODM) process. This paper will review ODM as practiced within the context of the governing paradigm of control. The paper will show the strengths of the process and areas for development. ODM is an important tool for managers within the complex socio-technical system that is nuclear power today. This paper summarises key points from a research thesis completed by the author to meet the requirements of an MSc program in 'Human Factors and System Safety'. (author)

Use of the Safety Monitor in operational decision-making at a nuclear generating facility

International Nuclear Information System (INIS)

Chien, Shan H.; Hook, Thomas G.; Lee, Roger J.

1998-01-01

The utilization of Safety Monitor at a nuclear generating facility in 1994 revolutionized the way US nuclear power plants manage configuration risks. At Southern California Edison (SCE) Company's San Onofre Nuclear Generating Station, it transformed probabilistic risk assessment (PRA) from a retrospective tool for understanding past risk into a prospective tool for controlling future risk. Since that time, many other nuclear utilities have taken aggressive steps in using PRA better to understand and manage risks associated with plant operation and maintenance. These utilities have employed a variety of methods ranging from systems similar to San Onofre's Safety Monitor to systems dramatically different in both technology and philosophy. In the development and use of its Safety Monitor, SCE has been guided by two philosophical goals: (1) maximize the objectivity of PRA-informed decision-making relative to managing configuration risks, and (2) ensure that risks are managed conservatively

Nuclear power plant operating experiences from the IAEA/NEA Incident Reporting System 1999-2002

International Nuclear Information System (INIS)

2003-01-01

Incident reporting has become an increasingly important aspect of the operation and regulation of all public health and safety-related industries. Diverse industries such as aeronautics, chemicals, pharmaceuticals and explosives all depend on operating experience feedback to provide lessons learned about safety. The Incident Reporting System (IRS) is an essential element of the system for feeding back international operating experience for nuclear power plants. IRS reports contain information on events of Safety significance with important lessons learned. These experiences assist in reducing or eliminating recurrence of events at other plants. The IRS is jointly operated and managed by the Nuclear Energy Agency (NEA), a semi-autonomous body within the Organisation for Economic Co-operation and Development (OECD), and the International Atomic Energy Agency (IAEA). It is important that sufficient national resources be allocated to enable timely and high quality reporting of events important to safety, and to share these events in the IRS database. The first report, which covered the period July 1996 - June 1999, was widely acclaimed and encouraged both agencies to prepare this second report in order to highlight important lessons learned from around 300 events reported to the IRS for the period July 1999 - December 2002. Several areas were selected in this report to show the range of important topics available in the IRS. These include different types of failure in a variety of plant systems, as well as human performance considerations. This report is primarily aimed at senior officials in industry and government who have decision-making roles in the nuclear power industry

IAEA activity on operator support systems in nuclear power plants

International Nuclear Information System (INIS)

Dounaev, V.; Fujita, Y.; Juslin, K.; Haugset, K.; Lux, I.; Naser, J.

1994-01-01

Various operator support systems for nuclear power plants are already operational or under development in the IAEA Member States. Operator support systems are based on intelligent data processing and, in addition to plant operation, they are also becoming more important for safety. A key feature of operator support systems is their availability to restructure data to increase its relevance for a given situation. This can improve the user's ability to identify plant mode, system state, and component state and to identify and diagnose faults. Operator support systems can also assist the user in planning and implementing corrective actions to improve the nuclear power plant's availability and safety. In September 1991, the IAEA Committee for Contractual Scientific Services approved the Co-ordinated Research Programme (CRP) on ''Operator Support Systems in Nuclear Power Plants'' in the framework of the Project ''Man-Machine Interface Studies''. The main objective of this programme is to provide guidance and technology transfer for the development and implementation of operator support systems. This includes the experience with human-machine interfaces and closely related issues such as instrumentation and control, the use of computers in nuclear power plants, and operator qualification. (author)

US nuclear power plant operating cost and experience summaries

International Nuclear Information System (INIS)

Kohn, W.E.; Reid, R.L.; White, V.S.

1998-02-01

NUREG/CR-6577, U.S. Nuclear Power Plant Operating Cost and Experience Summaries, has been prepared to provide historical operating cost and experience information on U.S. commercial nuclear power plants. Cost incurred after initial construction are characterized as annual production costs, representing fuel and plant operating and maintenance expenses, and capital expenditures related to facility additions/modifications which are included in the plant capital asset base. As discussed in the report, annual data for these two cost categories were obtained from publicly available reports and must be accepted as having different degrees of accuracy and completeness. Treatment of inconclusive and incomplete data is discussed. As an aid to understanding the fluctuations in the cost histories, operating summaries for each nuclear unit are provided. The intent of these summaries is to identify important operating events; refueling, major maintenance, and other significant outages; operating milestones; and significant licensing or enforcement actions. Information used in the summaries is condensed from annual operating reports submitted by the licensees, plant histories contained in Nuclear Power Experience, trade press articles, and the Nuclear Regulatory Commission (NRC) web site (www.nrc.gov)

US nuclear power plant operating cost and experience summaries

Energy Technology Data Exchange (ETDEWEB)

Kohn, W.E.; Reid, R.L.; White, V.S.

1998-02-01

NUREG/CR-6577, U.S. Nuclear Power Plant Operating Cost and Experience Summaries, has been prepared to provide historical operating cost and experience information on U.S. commercial nuclear power plants. Cost incurred after initial construction are characterized as annual production costs, representing fuel and plant operating and maintenance expenses, and capital expenditures related to facility additions/modifications which are included in the plant capital asset base. As discussed in the report, annual data for these two cost categories were obtained from publicly available reports and must be accepted as having different degrees of accuracy and completeness. Treatment of inconclusive and incomplete data is discussed. As an aid to understanding the fluctuations in the cost histories, operating summaries for each nuclear unit are provided. The intent of these summaries is to identify important operating events; refueling, major maintenance, and other significant outages; operating milestones; and significant licensing or enforcement actions. Information used in the summaries is condensed from annual operating reports submitted by the licensees, plant histories contained in Nuclear Power Experience, trade press articles, and the Nuclear Regulatory Commission (NRC) web site (www.nrc.gov).

Money Related Decommissioning and Funding Decision Making

International Nuclear Information System (INIS)

Goodman, Lynne S.

2008-01-01

'Money makes the world go round', as the song says. It definitely influences decommissioning decision-making and financial assurance for future decommissioning. This paper will address two money-related decommissioning topics. The first is the evaluation of whether to continue or to halt decommissioning activities at Fermi 1. The second is maintaining adequacy of financial assurance for future decommissioning of operating plants. Decommissioning costs considerable money and costs are often higher than originally estimated. If costs increase significantly and decommissioning is not well funded, decommissioning activities may be deferred. Several decommissioning projects have been deferred when decision-makers determined future spending is preferable than current spending, or when costs have risen significantly. Decommissioning activity timing is being reevaluated for the Fermi 1 project. Assumptions for waste cost-escalation significantly impact the decision being made this year on the Fermi 1 decommissioning project. They also have a major impact on the estimated costs for decommissioning currently operating plants. Adequately funding full decommissioning during plant operation will ensure that the users who receive the benefit pay the full price of the nuclear-generated electricity. Funding throughout operation also will better ensure that money is available following shutdown to allow decommissioning to be conducted without need for additional funds

Management of nuclear power plants for safe operation

International Nuclear Information System (INIS)

Kueffer, K.

1980-01-01

This lecture covers management aspects which have an immediate bearing on safety and identifies the objectives and tasks of management which are required for safe operation of a nuclear power plant and is based on the Codes of Practice and Safety Guides of the IAEA as well as arrangements in use at the Swiss Nuclear Power Station Beznau. This lecture - discusses the factors to be considered in structuring the operating organization, the support to be provided to plant management, the services and facilities needed and the management system for assuring the safety tasks are performed - describes the responsibilities of plant management and operating organization - outlines the requirements for recruitment, training and retraining as well as qualification and authorization of personnel - describes the programmes for maintenance, testing, examination, inspection, radiological protection, quality assurance, waste management, fuel management, emergency arrangement and security - describes the development of plant operating procedures including procedures to protect the personnel - outlines the requirements for initial and subsequent operation - describes the importance for evaluation and feedback of operating experience - describes the procedures for changes in hardware, procedures and set points - outlines the information flow and the requirements in reference to records and reports. (orig./RW)

Ensuring safe operation at the Loviisa nuclear power plant

International Nuclear Information System (INIS)

Regnell, B.

1985-01-01

Safe operation of a nuclear plant can be achieved only if the plant is designed according to stringent safety principles, if the construction and commissioning work meets high standards and finally if proper attention is paid to the safety aspects in all operational activities. Clearly formulated safety principles and standards are required for all these steps. In the early phases of the Loviisa project only a few IAEA codes of practice and safety guides were available. Their usefulness was, however, felt early, and valuable guidance was offered by them in formulating the quality assurance programme, for example. The paper describes the approach taken in order to achieve high operational safety at the first nuclear power station in Finland, the Loviisa plant. The involvement in the project of the plant owner, Imatran Voima Oy (IVO), was very large, the company serving as its own architect-engineer. Experience has shown that the thorough knowledge of the plant, down to the finest details, obtained by extensive participation in design, erection and commissioning of the plant, is invaluable in the actual operation of the plant. This manifests itself most clearly in the event of malfunctions and incidents or if modifications have to be undertaken. Many different activities affecting the operational safety can be identified: actual operation of the plant, including the creation and maintaining of technical specifications, procedures, instructions, documentation systems, etc.; maintenance, repair and modification work; in-service inspection and testing practices; component failure data collection and analysis; incident reporting, collection and evaluation systems; operator training; quality assurance programme; procedures and implementation; reviews of operational safety by an independent safety committee; and supervision by the safety authorities. In the paper, all these activities are described in some detail. (author)

Operation of Finnish nuclear power plants

International Nuclear Information System (INIS)

Tossavainen, K.

1993-03-01

Quarterly reports on the operation of Finnish nuclear power plants describe events and observations, relating to nuclear and radiation safety, which the Finnish Centre for Radiation and Nuclear Safety considers safety significant. Also other events of general interest are reported. The reports also include a summary of the radiation safety of plant personnel and the environment, as well as tabulated data on the plants' production and load factors

Assessing the structure of non-routine decision processes in Airline Operations Control.

Science.gov (United States)

Richters, Floor; Schraagen, Jan Maarten; Heerkens, Hans

2016-03-01

Unfamiliar severe disruptions challenge Airline Operations Control professionals most, as their expertise is stretched to its limits. This study has elicited the structure of Airline Operations Control professionals' decision process during unfamiliar disruptions by mapping three macrocognitive activities on the decision ladder: sensemaking, option evaluation and action planning. The relationship between this structure and decision quality was measured. A simulated task was staged, based on which think-aloud protocols were obtained. Results show that the general decision process structure resembles the structure of experts working under routine conditions, in terms of the general structure of the macrocognitive activities, and the rule-based approach used to identify options and actions. Surprisingly, high quality of decision outcomes was found to relate to the use of rule-based strategies. This implies that successful professionals are capable of dealing with unfamiliar problems by reframing them into familiar ones, rather than to engage in knowledge-based processing. Practitioner Summary: We examined the macrocognitive structure of Airline Operations Control professionals' decision process during a simulated unfamiliar disruption in relation to decision quality. Results suggest that successful professionals are capable of dealing with unfamiliar problems by reframing them into familiar ones, rather than to engage in knowledge-based processing.

Development of the job concept of a nuclear power plant operator

International Nuclear Information System (INIS)

Alpeev, A.S.; Bukrinskii, A.M.

1994-01-01

An important conclusion drawn in the aftermath of the 1979 accident at Three Mile Island 2 in the USA, in particular, in discussions, held in Stockholm in 1980 at the International Conference on Safety Problems, of the causes of this accident, was that the plant-operator concept employed at the time in western countries had to be changed. The concept presupposed that the operator's actions must be strictly limited by instructions which supposedly encompass all possible situations associated with the accidents. The principal problem facing the operator in this concept is to identify the situation in which the appropriate instruction can be selected for immediate execution. An error in identifying the situation could influence decisively the evolution of further events in the power block of the nuclear plant, and this is precisely what happened at Three Mile Island 2. For this reason, operator training was based mainly on identifying the initial events, which corresponded to a definite sequence of the further developments owing to the technical scheme and laws of thermophysical processes. Such operator training is based on an event tree which gives a graphical representation of the probable consequences of the development of events in an accident with a given initial event. It is believed that approximately 20 initial events (tree roots) form the basic collection of events, each of which has three to seven branches, i.e., an accident can evolve in several possible directions. Every branch point on each tree is identified by a definite collection of technological parameters, according to which the operator must be able to identify the situation. Under the present concept, when the situation is identified correctly, the search for the required control instruction and its execution is a secondary process

Operational limits and conditions and operating procedures for nuclear power plants. Safety guide

International Nuclear Information System (INIS)

2005-01-01

This Safety Guide was prepared as part of the Agency's programme for establishing safety standards relating to nuclear power plants. The present Safety Guide supersedes the IAEA Safety Guide on Operational Limits and Conditions for Nuclear Power Plants which was issued in 1979 as Safety Series No. 50-SG-O3. For a nuclear power plant to be operated in a safe manner, the provisions made in the final design and subsequent modifications shall be reflected in limitations on plant operating parameters and in the requirements on plant equipment and personnel. Under the responsibility of the operating organization, these shall be developed during the design safety evaluation as a set of operational limits and conditions (OLCs). A major contribution to compliance with the OLCs is made by the development and utilization of operating procedures (OPs) that are consistent with and fully implement the OLCs. The requirements for the OLCs and OPs are established in Section 5 of the IAEA Safety Requirements publication Safety of Nuclear Power Plants: Operation, which this Safety Guide supplements. The purpose of this Safety Guide is to provide guidance on the development, content and implementation of OLCs and OPs. The Safety Guide is directed at both regulators and owners/operators. This Safety Guide covers the concept of OLCs, their content as applicable to land based stationary power plants with thermal neutron reactors, and the responsibilities of the operating organization regarding their establishment, modification, compliance and documentation. The OPs to support the implementation of the OLCs and to ensure their observance are also within the scope of this Safety Guide. The particular aspects of the procedures for maintenance, surveillance, in-service inspection and other safety related activities in connection with the safe operation of nuclear power plants are outside the scope of this Safety Guide but can be found in other IAEA Safety Guides. Section 2 indicates the

Operational limits and conditions and operating procedures for nuclear power plants. Safety guide

International Nuclear Information System (INIS)

2000-01-01

This Safety Guide was prepared as part of the Agency's programme for establishing safety standards relating to nuclear power plants. The present Safety Guide supersedes the IAEA Safety Guide on Operational Limits and Conditions for Nuclear Power Plants which was issued in 1979 as Safety Series No. 50-SG-O3. For a nuclear power plant to be operated in a safe manner, the provisions made in the final design and subsequent modifications shall be reflected in limitations on plant operating parameters and in the requirements on plant equipment and personnel. Under the responsibility of the operating organization, these shall be developed during the design safety evaluation as a set of operational limits and conditions (OLCs). A major contribution to compliance with the OLCs is made by the development and utilization of operating procedures (OPs) that are consistent with and fully implement the OLCs. The requirements for the OLCs and OPs are established in Section 5 of the IAEA Safety Requirements publication Safety of Nuclear Power Plants: Operation, which this Safety Guide supplements. The purpose of this Safety Guide is to provide guidance on the development, content and implementation of OLCs and OPs. The Safety Guide is directed at both regulators and owners/operators. This Safety Guide covers the concept of OLCs, their content as applicable to land based stationary power plants with thermal neutron reactors, and the responsibilities of the operating organization regarding their establishment, modification, compliance and documentation. The OPs to support the implementation of the OLCs and to ensure their observance are also within the scope of this Safety Guide. The particular aspects of the procedures for maintenance, surveillance, in-service inspection and other safety related activities in connection with the safe operation of nuclear power plants are outside the scope of this Safety Guide but can be found in other IAEA Safety Guides. Section 2 indicates the

Changing nuclear plant operating limits during startup and shutdown

International Nuclear Information System (INIS)

Arnold, E.C.; Carlson, R.W.; Ray, N.K.; Roarty, D.H.

1990-01-01

During startup and shutdown operation of pressurized water reactor (PWR) nuclear power plants, a low pressure decay heat removal system is used to maintain core cooling. During these phases of operation, there are numerous operating practices and design limits to meet special and sometimes conflicting requirements unique to these operations. This paper evaluates the impact and interdependencies of recent issues on plant operation and design

Quality assurance during operation of nuclear power plants

International Nuclear Information System (INIS)

1981-01-01

This Safety Guide provides requirements and recommendations for the establishment and implementation of quality assurance for activities important to safety during commissioning, operation and decommissioning of a nuclear power plant, hereinafter referred to in this Guide as the operation phase or operation. It applies to activities such as: operating, inspecting, testing, commissioning, refuelling, maintaining, repairing, modifying and eventual shut-down and decommissioning of nuclear power plants. It applies also to associated activities related to safety, such as environmental monitoring and responses to emergencies

Nuclear power plant operation 2016. Pt. 1

Energy Technology Data Exchange (ETDEWEB)

Anon.

2017-05-15

A report is given on the operating results achieved in 2016, events important to plant safety, special and relevant repair, and retrofit measures from nuclear power plants in Germany. Reports about nuclear power plants in Belgium, Finland, the Netherlands, Switzerland, and Spain will be published in a further issue.

Safety of nuclear power plants: Operation. Safety requirements

International Nuclear Information System (INIS)

2004-01-01

The safety of a nuclear power plant is ensured by means of its proper siting, design, construction and commissioning, followed by the proper management and operation of the plant. In a later phase, proper decommissioning is required. This Safety Requirements publication supersedes the Code on the Safety of Nuclear Power Plants: Operation, which was issued in 1988 as Safety Series No. 50-C-O (Rev. 1). The purpose of this revision was: to restructure Safety Series No. 50-C-O (Rev. 1) in the light of the basic objectives, concepts and principles in the Safety Fundamentals publication The Safety of Nuclear Installations. To be consistent with the requirements of the International Basic Safety Standards for Protection against Ionizing Radiation and for the Safety of Radiation Sources. And to reflect current practice and new concepts and technical developments. Guidance on fulfillment of these Safety Requirements may be found in the appropriate Safety Guides relating to plant operation. The objective of this publication is to establish the requirements which, in the light of experience and the present state of technology, must be satisfied to ensure the safe operation of nuclear power plants. These requirements are governed by the basic objectives, concepts and principles that are presented in the Safety Fundamentals publication The Safety of Nuclear Installations. This publication deals with matters specific to the safe operation of land based stationary thermal neutron nuclear power plants, and also covers their commissioning and subsequent decommissioning

Safety of nuclear power plants: Operation. Safety requirements

International Nuclear Information System (INIS)

2003-01-01

The safety of a nuclear power plant is ensured by means of its proper siting, design, construction and commissioning, followed by the proper management and operation of the plant. In a later phase, proper decommissioning is required. This Safety Requirements publication supersedes the Code on the Safety of Nuclear Power Plants: Operation, which was issued in 1988 as Safety Series No. 50-C-O (Rev. 1). The purpose of this revision was: to restructure Safety Series No. 50-C-O (Rev. 1) in the light of the basic objectives, concepts and principles in the Safety Fundamentals publication The Safety of Nuclear Installations. To be consistent with the requirements of the International Basic Safety Standards for Protection against Ionizing Radiation and for the Safety of Radiation Sources. And to reflect current practice and new concepts and technical developments. Guidance on fulfillment of these Safety Requirements may be found in the appropriate Safety Guides relating to plant operation. The objective of this publication is to establish the requirements which, in the light of experience and the present state of technology, must be satisfied to ensure the safe operation of nuclear power plants. These requirements are governed by the basic objectives, concepts and principles that are presented in the Safety Fundamentals publication The Safety of Nuclear Installations. This publication deals with matters specific to the safe operation of land based stationary thermal neutron nuclear power plants, and also covers their commissioning and subsequent decommissioning

Safety of nuclear power plants: Operation. Safety requirements

International Nuclear Information System (INIS)

2000-01-01

The safety of a nuclear power plant is ensured by means of its proper siting, design, construction and commissioning, followed by the proper management and operation of the plant. In a later phase, proper decommissioning is required. This Safety Requirements publication supersedes the Code on the Safety of Nuclear Power Plants: Operation, which was issued in 1988 as Safety Series No. 50-C-O (Rev. 1). The purpose of this revision was: to restructure Safety Series No. 50-C-O (Rev. 1) in the light of the basic objectives, concepts and principles in the Safety Fundamentals publication The Safety of Nuclear Installations; to be consistent with the requirements of the International Basic Safety Standards for Protection against Ionizing Radiation and for the Safety of Radiation Sources; and to reflect current practice and new concepts and technical developments. Guidance on fulfillment of these Safety Requirements may be found in the appropriate Safety Guides relating to plant operation. The objective of this publication is to establish the requirements which, in the light of experience and the present state of technology, must be satisfied to ensure the safe operation of nuclear power plants. These requirements are governed by the basic objectives, concepts and principles that are presented in the Safety Fundamentals publication The Safety of Nuclear Installations. This publication deals with matters specific to the safe operation of land based stationary thermal neutron nuclear power plants, and also covers their commissioning and subsequent decommissioning

Application of expert system to nuclear power plant operation and guidance system

International Nuclear Information System (INIS)

Goto, M.; Takada, Y.

1990-01-01

For a nuclear power plant, it is important that an expert system supplies useful information to the operator to meet the increasing demand for high-level plant operation. It is difficult to build a user-friendly expert system that supplies useful information in real time using existing general-purpose expert system shells. Therefore a domain-specific expert system shell with a useful knowledge representation for problem-solving in nuclear power plant operation was selected. The Plant Table (P/T) representation format was developed for description of a production system for nuclear power plant operation knowledge. The P/T consists of plant condition representation designed to process multiple inputs and single output. A large number of operation inputs for several plant conditions are divided into 'timing conditions', 'preconditions' and 'completion conditions' to facilitate knowledge-base build-up. An expert system for a Nuclear Power Plant Operation and Guidance System utilizing the P/T was developed to assist automatic plant operation and surveillance test operation. In these systems, automatic plant operation signals to the plant equipment and operation guidance messages to the operators are both output based on the processing and assessment of plant operation conditions by the P/T. A surveillance test procedure guide for major safety-related systems, such as those for emergency core cooling systems, is displayed on a CRT (Cathode Ray Tube) and test results are printed out. The expert system for a Nuclear Power Plant Operation and Guidance System has already been successfully applied to Japanese BWR plants

Higher operational safety of nuclear power plants by evaluating the behaviour of operating personnel

International Nuclear Information System (INIS)

Mertins, M.; Glasner, P.

1990-01-01

In the GDR power reactors have been operated since 1966. Since that time operational experiences of 73 cumulative reactor years have been collected. The behaviour of operating personnel is an essential factor to guarantee the safety of operation of the nuclear power plant. Therefore a continuous analysis of the behaviour of operating personnel has been introduced at the GDR nuclear power plants. In the paper the overall system of the selection, preparation and control of the behaviour of nuclear power plant operating personnel is presented. The methods concerned are based on recording all errors of operating personnel and on analyzing them in order to find out the reasons. The aim of the analysis of reasons is to reduce the number of errors. By a feedback of experiences the nuclear safety of the nuclear power plant can be increased. All data necessary for the evaluation of errors are recorded and evaluated by a computer program. This method is explained thoroughly in the paper. Selected results of error analysis are presented. It is explained how the activities of the personnel are made safer by means of this analysis. Comparisons with other methods are made. (author). 3 refs, 4 figs

Decontamination of operational nuclear power plants

International Nuclear Information System (INIS)

1981-06-01

In order to reduce the radiation fields around nuclear power plants, and, consequently, to limit the radiation exposure of and dose commitments to the operating and maintenance personnel, the contamination build-up should be kept to a minimum. The most fruitful approach, from the point of view of economics and efficiency, is to tackle the problems of contamination and decontamination in the design and construction phases of the reactor. To do this, knowledge gained from the operation of existing power reactors should be used to make improvements in new designs. New structural materials with low corrosion rates or whose constituents are not activated by neutrons should also be used. For older reactors, in most cases it is already too late to incorporate design changes without extensive and expensive modifications. For these plants, decontamination remains the most efficient way to reduce radiation fields. The aim of this report is to deal with the different decontamination methods that may be applied to nuclear power plant circuits and equipment during operation. The factors that have to be considered in determining the type and the extent of the methods used are the engineering and the planning of the decontamination operation and the treatment of the resulting waste generated during the process are also discussed

Ex post power economic analysis of record of decision operational restrictions at Glen Canyon Dam.

Energy Technology Data Exchange (ETDEWEB)

Veselka, T. D.; Poch, L. A.; Palmer, C. S.; Loftin, S.; Osiek, B; Decision and Information Sciences; Western Area Power Administration

2010-07-31

On October 9, 1996, Bruce Babbitt, then-Secretary of the U.S. Department of the Interior signed the Record of Decision (ROD) on operating criteria for the Glen Canyon Dam (GCD). Criteria selected were based on the Modified Low Fluctuating Flow (MLFF) Alternative as described in the Operation of Glen Canyon Dam, Colorado River Storage Project, Arizona, Final Environmental Impact Statement (EIS) (Reclamation 1995). These restrictions reduced the operating flexibility of the hydroelectric power plant and therefore its economic value. The EIS provided impact information to support the ROD, including an analysis of operating criteria alternatives on power system economics. This ex post study reevaluates ROD power economic impacts and compares these results to the economic analysis performed prior (ex ante) to the ROD for the MLFF Alternative. On the basis of the methodology used in the ex ante analysis, anticipated annual economic impacts of the ROD were estimated to range from approximately $15.1 million to $44.2 million in terms of 1991 dollars ($1991). This ex post analysis incorporates historical events that took place between 1997 and 2005, including the evolution of power markets in the Western Electricity Coordinating Council as reflected in market prices for capacity and energy. Prompted by ROD operational restrictions, this analysis also incorporates a decision made by the Western Area Power Administration to modify commitments that it made to its customers. Simulated operations of GCD were based on the premise that hourly production patterns would maximize the economic value of the hydropower resource. On the basis of this assumption, it was estimated that economic impacts were on average $26.3 million in $1991, or $39 million in $2009.

Selection/licensing of nuclear power plant operators

International Nuclear Information System (INIS)

Saari, L.M.

1983-07-01

An important aspect of nuclear power plant (NPP) safety is the reactor operator in the control room. The operators are the first individuals to deal with an emergency situation, and thus, effective performance on their part is essential for safe plant operations. Important issues pertaining to NPP reactor operators would fall within the personnel subsystem of our safety system analysis. While there are many potential aspects of the personnel subsystem, a key first step in this focus is the selection of individuals - attempting to choose individuals for the job of reactor operator who will safely perform the job. This requires a valid (job-related) selection process. Some background information on the Nuclear Regulatory Commission (NRC) licensing process used for selecting NPP reactor operators is briefly presented and a description of a research endeavor now underway at Battelle for developing a valid reactor operator licensing examination is included

On thermoeconomics of energy systems at variable load conditions: Integrated optimization of plant design and operation

International Nuclear Information System (INIS)

Piacentino, A.; Cardona, F.

2007-01-01

Thermoeconomics has been assuming a growing role among the disciplines oriented to the analysis of energy systems, its different methodologies allowing solution of problems in the fields of cost accounting, plant design optimisation and diagnostic of malfunctions. However, the thermoeconomic methodologies as such are particularly appropriate to analyse large industrial systems at steady or quasi-steady operation, but they can be hardly applied to small to medium scale units operating in unsteady conditions to cover a variable energy demand. In this paper, the fundamentals of thermoeconomics for systems operated at variable load are discussed, examining the cost formation process and, separately, the cost fractions related to capital depreciation (which require additional distinctions with respect to plants in steady operation) and to exergy consumption. The relevant effects of the efficiency penalty due to off design operation on the exergetic cost of internal flows are also examined. An original algorithm is proposed for the integrated optimization of plant design and operation based on an analytical solution by the Lagrange multipliers method and on a multi-objective decision function, expressed either in terms of net cash flow or primary energy saving. The method is suitable for application in complex energy systems, such as 'facilities of components of a same product' connected to external networks for power or heat distribution. For demonstrative purposes, the proposed thermoeconomically aided optimization is performed for a grid connected trigeneration system to be installed in a large hotel

A method and application study on holistic decision tree for human reliability analysis in nuclear power plant

International Nuclear Information System (INIS)

Sun Feng; Zhong Shan; Wu Zhiyu

2008-01-01

The paper introduces a human reliability analysis method mainly used in Nuclear Power Plant Safety Assessment and the Holistic Decision Tree (HDT) method and how to apply it. The focus is primarily on providing the basic framework and some background of HDT method and steps to perform it. Influence factors and quality descriptors are formed by the interview with operators in Qinshan Nuclear Power Plant and HDT analysis performed for SGTR and SLOCA based on this information. The HDT model can use a graphic tree structure to indicate that error rate is a function of influence factors. HDT method is capable of dealing with the uncertainty in HRA, and it is reliable and practical. (authors)

Evolution of the future plants operation for a better safety

International Nuclear Information System (INIS)

Papin, B.; Malvache, P.

1994-01-01

This paper describes a coordinated research project of the french CEA, addressing to the evolutions in plant operation apt to bring perceptible and assessable improvement in the operational safety. This program has been scheduled for the 1992-1996 period, with a global 40 men/year effort. The present status of the two main parts of the project is presented: ESCRIME (program aiming at defining the optimal share of tasks between humans and computers in plant operation), IMAGIN (research in the domain of plant information management, in order to ensure the global coherence of the image of the plant, used by the different actors in plant operation). (authors). 3 refs., 4 figs

The Unbalanced Linguistic Aggregation Operator in Group Decision Making

Directory of Open Access Journals (Sweden)

Li Zou

2012-01-01

Full Text Available Many linguistic aggregation methods have been proposed and applied in the linguistic decision-making problems. In practice, experts need to assess a number of values in a side of reference domain higher than in the other one; that is, experts use unbalanced linguistic values to express their evaluation for problems. In this paper, we propose a new linguistic aggregation operator to deal with unbalanced linguistic values in group decision making, we adopt 2-tuple representation model of linguistic values and linguistic hierarchies to express unbalanced linguistic values, and moreover, we present the unbalanced linguistic ordered weighted geometric operator to aggregate unbalanced linguistic evaluation values; a comparison example is given to show the advantage of our method.

Development of a dynamic operation permission system to support operations in an anomalous situation of PWR plants

International Nuclear Information System (INIS)

Gofuku, Akio; Nishio, Takuya; Ohi, Tadashi; Ito, Koji

2005-01-01

This paper describes a proto-type dynamic operation permission system to avoid commission errors of operators. The system lies between CRT-based operation panels and plant control systems and checks an operation by operators if it follows typical operation procedure described in operation manuals and it has suitable effects on plant condition. The applicability of the proto-type system is demonstrated through the application to the recovery operations of a steam generator tube rupture accident of a three-loop pressurized water reactor plant

A survey on the technologies and cases for the cognitive models of nuclear power plant operators

International Nuclear Information System (INIS)

Lee, Yong Hee; Chun, Se Woo; Seo, Sang Moon; Lee, Hyun Chul

1993-04-01

To enhance the safety and availability of nuclear power plants, it is necessary to develop the methodologies which can systematically analyze the interrelationships between plant operators and main process systems. Operator congnitive models enable to provide an explicit method to analyze how operator's congitive behavior reacts to the behavior of system changes. However, because no adequate model has been developed up to now, it is difficult to take an effective approach for the review, assessment and improvement of human factors. In this study, we have surveyed the techniques and the cases of operator model development, aiming to develop an operator's model as one of human engineering application methodologies. We have analyzed the cognitive characteristics of decision-making, which is one of the principal factors for modeling, and reviewed the methodologies and implementation thechniques used in the cases of the model development. We investigated the tendencies of the model developments by reviewing ten cases and especially CES, INTEROPS and COSIMO models which have been developed or are under development in nuclear fields. Also, we summarized the cognitive characteristics to be considered in the modeling for the purpose of modeling operator's decision-making. For modeling methodologies, we found a trend of the modeling that is software simulations based on the artificial intelligence technologies, especially focused in knowledge representation methods. Based on the results of our survey, we proposed a development approach and several urgent research subjects. We suggested the development simulation tools which can be applicable to the review, assessment and improvement of human factors, by implementing them as softwares using expert system development tools. The results of this study have been applied to our long-term project named 'The Development of Human Engineering Technologies.' (Author)

Operating procedure automation to enhance safety of nuclear power plants

International Nuclear Information System (INIS)

Husseiny, A.A.; Sabri, Z.A.; Adams, S.K.; Rodriguez, R.J.; Packer, D.; Holmes, J.W.

1989-01-01

Use of logic statements and computer assist are explored as means for automation and improvement on design of operating procedures including those employed in abnormal and emergency situations. Operating procedures for downpower and loss of forced circulation are used for demonstration. Human-factors analysis is performed on generic emergency operating procedures for three strategies of control; manual, semi-automatic and automatic, using standard emergency operating procedures. Such preliminary analysis shows that automation of procedures is feasible provided that fault-tolerant software and hardware become available for design of the controllers. Recommendations are provided for tests to substantiate the promise of enhancement of plant safety. Adequate design of operating procedures through automation may alleviate several major operational problems of nuclear power plants. Also, automation of procedures is necessary for partial or overall automatic control of plants. Fully automatic operations are needed for space applications while supervised automation of land-based and offshore plants may become the thrust of new generation of nulcear power plants. (orig.)

Preparation of Leaders to Make Decisions in Peacekeeping Operations

National Research Council Canada - National Science Library

Pappal, Michael

2002-01-01

.... Areas investigated include personal confidence in decision-making of various types, amount of training and education received in peace operations, and assessments of Army preparations of leaders...

Operation reports of nuclear power plants

International Nuclear Information System (INIS)

1983-01-01

The requirements aiming to standardize the program of nuclear power plant operation report, required by Brazilian Energy Commission - CNEN - to evaluate the activities related to the nuclear technical safety and to the radiation protection during the units operational phase, are showed. (E.G.) [pt

Operational safety of nuclear power plants

International Nuclear Information System (INIS)

Tanguy, P.

1987-01-01

The operational safety of nuclear power plants has become an important safety issue since the Chernobyl accident. A description is given of the various aspects of operational safety, including the importance of human factors, responsibility, the role and training of the operator, the operator-machine interface, commissioning and operating procedures, experience feedback, and maintenance. The lessons to be learnt from Chernobyl are considered with respect to operator errors and the management of severe accidents. Training of personnel, operating experience feedback, actions to be taken in case of severe accidents, and international cooperation in the field of operational safety, are also discussed. (U.K.)

Commissioning and Operational Experience in Power Reactor Fuel Reprocessing Plant

Energy Technology Data Exchange (ETDEWEB)

Pradhan, S., E-mail: spradhan@barctara.gov.in [Tarapur Based Reprocessing Plant, Bhabha Atomic Research Centre, Tarapur (India)

2014-10-15

After completing design, construction, commissioning, operation and maintenance experience of the reprocessing plants at Tarapur, Mumbai and Kalpakkam a new reprocessing plant is commissioned and put into operation at BARC, Tarapur since 2011. Subsequent to construction clearance, commissioning of the plant is taken in many steps with simultaneous review by design and safety committees. In spite of vast experience, all the staff was retrained in various aspects of process and utility operations and in operation of innovative changes incorporated in the design. Operating personnel are licensed through an elaborate procedure consisting of various check lists followed by personnel interview. Commissioning systems were divided in sub-systems. Sub-systems were commissioned independently and later integrated testing was carried out. For commissioning, extreme operating conditions were identified in consultation with designers and detailed commissioning procedures were made accordingly. Commissioning was done in different conditions to ensure safety, smooth operation and maintainability. Few modifications were carried out based on commissioning experience. Technical specifications for operation of the plant are made in consultation with designers and reviewed by safety committees. Operation of the plant was carried out after successful commissioning trials with Deep Depleted Uranium (DDU). Emergency operating procedures for each design basis accident were made. Performance of various systems, subsystems are quite satisfactory and the plant has given very good capacity factor. (author)

Increase of hydroelectric power plant operation reliability

International Nuclear Information System (INIS)

Koshumbaev, M.B.

2006-01-01

The new design of the turbine of hydroelectric power plant (HPP) is executed in the form of a pipe with plates. Proposed solution allows increasing the hydroelectric power plant capacity at existing head and water flow. At that time the HPP turbine reliability is increase, its operation performances are improving. Design efficiency is effective mostly for small-scale and micro-HPP due to reliable operation, low-end technology, and harmless ecological application. (author)

Typical IAEA operations at a fuel fabrication plant

International Nuclear Information System (INIS)

Morsy, S.

1984-01-01

The IAEA operations performed at a typical Fuel Fabrication Plant are explained. To make the analysis less general the case of Low Enriched Uranium (LEU) Fuel Fabrication Plants is considered. Many of the conclusions drawn from this analysis could be extended to other types of fabrication plants. The safeguards objectives and goals at LEU Fuel Fabrication Plants are defined followed by a brief description of the fabrication process. The basic philosophy behind nuclear material stratification and the concept of Material Balance Areas (MBA's) and Key Measurement Points (KMP's) is explained. The Agency operations and verification methods used during physical inventory verifications are illustrated

Improving plant state information for better operational safety

International Nuclear Information System (INIS)

Girard, C.; Olivier, E.; Grimaldi, X.

1994-01-01

Nuclear Power Plant (NPP) safety is strongly dependent on components' reliability and particularly on plant state information reliability. This information, used by the plant operators in order to produce appropriate actions, have to be of a high degree of confidence, especially in accidental conditions where safety is threatened. In this perspective, FRAMATOME, EDF and CEA have started a joint research program to prospect different solutions aiming at a better reliability for critical information needed to safety operate the plant. This paper gives the main results of this program and describes the developments that have been made in order to assess reliability of different information systems used in a Nuclear Power Plant. (Author)

Operating experience with nuclear power plants 2013; Betriebserfahrungen mit Kernkraftwerken 2013

Energy Technology Data Exchange (ETDEWEB)

Anon.

2014-07-01

The VGB Technical Committee 'Nuclear Plant Operation' has been exchanging operating experience about nuclear power plants for more than 30 years. Plant operators from several European countries are participating in the exchange. A report is given on the operating results achieved in 2013, events important to plant safety, special and relevant repair, and retrofit measures from Belgium, Germany, Finland, the Netherlands, Switzerland, and Spain. (orig.)

Dual hesitant pythagorean fuzzy Hamacher aggregation operators in multiple attribute decision making

Directory of Open Access Journals (Sweden)

Wei Guiwu

2017-09-01

Full Text Available In this paper, we investigate the multiple attribute decision making (MADM problem based on the Hamacher aggregation operators with dual Pythagorean hesitant fuzzy information. Then, motivated by the ideal of Hamacher operation, we have developed some Hamacher aggregation operators for aggregating dual hesitant Pythagorean fuzzy information. The prominent characteristic of these proposed operators are studied. Then, we have utilized these operators to develop some approaches to solve the dual hesitant Pythagorean fuzzy multiple attribute decision making problems. Finally, a practical example for supplier selection in supply chain management is given to verify the developed approach and to demonstrate its practicality and effectiveness.

Operation of Finnish nuclear power plants

International Nuclear Information System (INIS)

Tossavainen, K.

1991-08-01

In the Quarterly Reports on the operation of the Finnish nuclear power plants such events and observations are described relating to nuclear and radiation safety which the Finnish Centre for Radiation and Nuclear Safety considers safety significant. Also other events of general interest are reported. The report also includes a summary of the radiation safety of the plants' workers and the environment, as well as tabulated data on the production and load factors of the plants. The Finnish nuclear power plant units Loviisa 1 and 2 as well as TVO I and II were in commercial operation during the whole first quarter of 1991. The load factor average was 99.1 %. Failures have been detected in the uppermost spacing lattices of nuclear fuel bundles removed from the Loviisa nuclear reactors. Further investigations into the significance of the failures have been initiated. In this quarter, renewed cooling systems for the instrumentation area were introduced at Loviisa 1. The modifications made in the systems serve to ensure reliable cooling of the area even during the hottest summer months when the possibility exists that the temperature of the automation equipment could rise too high causing malfunctions which could endanger plant safety. Occupational radiation doses and external releases of radioactivity were below prescribed limits in this quarter. Only small amounts of radioactive substances originating in nuclear power plants were detected in samples taken in the vicinity of nuclear power plants

Kursk ASSET brings praise for plant operators

International Nuclear Information System (INIS)

Anon.

1992-01-01

An Assessment of Safety Significant Events Team (ASSET) from the International Atomic Energy Agency (IAEA) visited Kursk on 19-31 July 1992 - the first time such a group had been to a RBMK reactor site. Kursk is a four unit station and the IAEA Team was able to consider safety significant events over its 45 reactor-year history. all four units have good operating records, with lifetime load factors of 70-80%. The ASSET's aim was to consider the plants current safety provisions for prevention of accidents and incidents. ASSET recommendations may cover the design and operability of the plant, personnel or operating procedures. At Kursk the Team found that ''highly qualified plant management and a very dedicated and knowledgeable operating staff'' was a major asset. They found a sound maintenance programme although some aspects of the facility appeared neglected. This was attributed to Russian industrial priorities that focused on functionality rather than appearance. it was in the test and maintenance personnel that the ASSET mission found the safety culture weakest. Some of their recommendations are reported in this article. (Author)

Sequential decision reliability concept and failure rate assessment

International Nuclear Information System (INIS)

Ciftcioglu, O.

1990-11-01

Conventionally, a reliability concept is considered together with both each basic unit and their integration in a complicated large scale system such as a nuclear power plant (NPP). Basically, as the plant's operational status is determined by the information obtained from various sensors, the plant's reliability and the risk assessment is closely related to the reliability of the sensory information and hence the sensor components. However, considering the relevant information-processing systems, e.g. fault detection processors, there exists a further question about the reliability of such systems, specifically the reliability of the systems' decision-based outcomes by means of which the further actions are performed. To this end, a general sequential decision reliability concept and the failure rate assessment methodology is introduced. The implications of the methodology are investigated and the importance of the decision reliability concept in system operation is demonstrated by means of sensory signals in real-time from the Borssele NPP in the Netherlands. (author). 21 refs.; 8 figs

Operation of Finnish nuclear power plants

International Nuclear Information System (INIS)

Tossavainen, K.

1991-02-01

During the third quarter of 1990 the Finnish nuclear power plant units Loviisa 1 and 2 and TVO I and II were in commercial operation for most of the time. The annual maintenance outages of the Loviisa plant units were held during the report period. All events during this quarter are classified as Level hero (Below Scale) on the International Nuclear Event Scale. Occupational radiation doses and external releases of radioactivity were below authorised limits. Only small amounts of radioactive substances originating in nuclear power plants were detected in samples taken in the vicinity of nuclear power plants

Use of wind power forecasting in operational decisions.

Energy Technology Data Exchange (ETDEWEB)

Botterud, A.; Zhi, Z.; Wang, J.; Bessa, R.J.; Keko, H.; Mendes, J.; Sumaili, J.; Miranda, V. (Decision and Information Sciences); (INESC Porto)

2011-11-29

The rapid expansion of wind power gives rise to a number of challenges for power system operators and electricity market participants. The key operational challenge is to efficiently handle the uncertainty and variability of wind power when balancing supply and demand in ths system. In this report, we analyze how wind power forecasting can serve as an efficient tool toward this end. We discuss the current status of wind power forecasting in U.S. electricity markets and develop several methodologies and modeling tools for the use of wind power forecasting in operational decisions, from the perspectives of the system operator as well as the wind power producer. In particular, we focus on the use of probabilistic forecasts in operational decisions. Driven by increasing prices for fossil fuels and concerns about greenhouse gas (GHG) emissions, wind power, as a renewable and clean source of energy, is rapidly being introduced into the existing electricity supply portfolio in many parts of the world. The U.S. Department of Energy (DOE) has analyzed a scenario in which wind power meets 20% of the U.S. electricity demand by 2030, which means that the U.S. wind power capacity would have to reach more than 300 gigawatts (GW). The European Union is pursuing a target of 20/20/20, which aims to reduce greenhouse gas (GHG) emissions by 20%, increase the amount of renewable energy to 20% of the energy supply, and improve energy efficiency by 20% by 2020 as compared to 1990. Meanwhile, China is the leading country in terms of installed wind capacity, and had 45 GW of installed wind power capacity out of about 200 GW on a global level at the end of 2010. The rapid increase in the penetration of wind power into power systems introduces more variability and uncertainty in the electricity generation portfolio, and these factors are the key challenges when it comes to integrating wind power into the electric power grid. Wind power forecasting (WPF) is an important tool to help

Decision support systems for power plants impact on the living standard

International Nuclear Information System (INIS)

Chatzimouratidis, Athanasios I.; Pilavachi, Petros A.

2012-01-01

Highlights: ► Ten major types of power plant are evaluated as to their impact on living standard. ► Uncertainty in both criteria performance and criteria weighting is considered. ► PROMETHEE II method, 12 criteria and 13 scenarios are used. ► Results are presented per scenario and per type of power plant. ► Optimal solution depends on scenario assumptions of the decision maker. - Abstract: In developed countries, the quality of life is of first priority and an overall assessment of power plant impact on the living standard requires a multicriteria analysis of both positive and negative factors incorporating uncertainty in criteria performance and probability assessment of weighting factors. This study incorporates PROMETHEE II to assess 10 major types of power plant under 12 criteria, 13 fixed and infinite customized probability assessed weight set scenarios. The power plants considered are coal/lignite, oil, natural gas turbine, natural gas combined cycle, nuclear, hydro, wind, photovoltaic, biomass and geothermal. Geothermal, wind and photovoltaic power plants are excellent choices in most of the cases and biomass and hydro should also be preferred to nuclear and fossil fuel. Among nuclear and fossil fuel the choice is based on the specific parameters of each case examined while natural gas technologies have specific advantages. The motivation of this study was to provide a tool for the decision-maker to evaluate all major types of power plant incorporating multicriteria and customized probability assessment of weighting factors.

Factor best of ALWR features into operating plants

International Nuclear Information System (INIS)

Strauss, S.D.

1997-01-01

This article describes how many features of advanced light-water reactor designs are applicable to existing plants. While no new plants are being ordered, some advanced features have found their way into existing units and have been incorporated into the design of plants being built overseas. Ironically, two of the advanced light-water reactor (ALWR) plant designs--the ABWR and the System 80+--were finally approved by the US Nuclear Regulatory Commission (NRC) at the end of last year. Yet US utilities are probably further away from ordering a new nuclear unit than they ever have been. But that doesn't make the program irrelevant. Design advances from this program can affect the economics of nuclear power at a time when owner/operators are striving to compete in a less restrictive market for generation. Advances that can be considered by operating plants emanate from two major programs: (1) the standard plant designs which began in the late 1970s and (2) the ALWR program which sought--successfully, although it took a decade--to precertify designs and lessen the licensing burden on those contemplating a new unit. By using proven technology to simplify plants with higher design margins and enhanced safety features, the ALWR program's goal was to make new plants less expensive, safer, and easier to operate and maintain than their predecessors

Computer visualization for enhanced operator performance for advanced nuclear power plants

International Nuclear Information System (INIS)

Simon, B.H.; Raghavan, R.

1993-01-01

The operators of nuclear power plants are presented with an often uncoordinated and arbitrary array of displays and controls. Information is presented in different formats and on physically dissimilar instruments. In an accident situation, an operator must be very alert to quickly diagnose and respond to the state of the plant as represented by the control room displays. Improvements in display technology and increased automation have helped reduce operator burden; however, too much automation may lead to operator apathy and decreased efficiency. A proposed approach to the human-system interface uses modern graphics technology and advances in computational power to provide a visualization or ''virtual reality'' framework for the operator. This virtual reality comprises a simulated perception of another existence, complete with three-dimensional structures, backgrounds, and objects. By placing the operator in an environment that presents an integrated, graphical, and dynamic view of the plant, his attention is directly engaged. Through computer simulation, the operator can view plant equipment, read local displays, and manipulate controls as if he were in the local area. This process not only keeps an operator involved in plant operation and testing procedures, but also reduces personnel exposure. In addition, operator stress is reduced because, with realistic views of plant areas and equipment, the status of the plant can be accurately grasped without interpreting a large number of displays. Since a single operator can quickly ''visit'' many different plant areas without physically moving from the control room, these techniques are useful in reducing labor requirements for surveillance and maintenance activities. This concept requires a plant dynamic model continuously updated via real-time process monitoring. This model interacts with a three-dimensional, solid-model architectural configuration of the physical plant

Evaluation of nuclear power plant operator's ability

International Nuclear Information System (INIS)

Wei Li; He Xuhong; Zhao Bingquan

2004-01-01

Based on the quantitative research on nuclear power plant (NPP) operator's psychological characteristics and performance, the Borda's method of fuzzy mathematics combined with the character of operator's task is used to evaluate their abilities. The result provides the reference for operator's reliability research and psychological evaluation. (author)

The safety approach in the operation of EDF power plants

International Nuclear Information System (INIS)

Bertron, L.; Mira, J.J.

1988-01-01

To get a view on what is involved in maintaining a high level of safety in the operation of EdF nuclear power plants, it may be recalled that in 1987, 76 % of the EdF production was nuclear. The nuclear plants include thirty-four standard PWR 900 plants, fourteen PWR 1300 plants, the 305 MW SENA PWR, the four 500 MW GCR: CHINON A3 plant, St-LAURENT A1 (390 MW), A2 (450 MW) and BUGEY 1 (540 MW), the 233 MW PHENIX fast breeder reactor and the CREYS-MALVILLE 1200 MW fast breeder reactor, now being prepared for a new startup after the 1987 incident. So the importance of a safe operation of this investment is considerable for EdF, which is the designer, owner, industrial architect and operator. According to the French regulations, EdF is responsible for the safe operation of its power plants. A considerable human component is also at stake, as the safe operation of plants implies all the personnel to varying degrees. There are 15,000 such employees, all of whom have to be trained, competent and motivated. The operation of this system for 340 reactor-years has to-date resulted in no incident of any significant impact on the environment. Right from the start, safety in operation has always been an essential and clearly stated priority. Among other lessons the Three-Mile Island and Chernobyl accidents have reinforced the conviction that the human factors, the man-machine interface, and the safety culture were determining elements. With forty-eigh PWR plants in service, the problem is to maintain safe operation of a system now running at cruising speed, but also including some units (particularly the GCRs) that must be prepared for decommissioning. In addition EDF has to demonstrate the safe operations of CREYS MALVILLE, fast breeder reactor

Operator-based metric for nuclear operations automation assessment

Energy Technology Data Exchange (ETDEWEB)

Zacharias, G.L.; Miao, A.X.; Kalkan, A. [Charles River Analytics Inc., Cambridge, MA (United States)] [and others

1995-04-01

Continuing advances in real-time computational capabilities will support enhanced levels of smart automation and AI-based decision-aiding systems in the nuclear power plant (NPP) control room of the future. To support development of these aids, we describe in this paper a research tool, and more specifically, a quantitative metric, to assess the impact of proposed automation/aiding concepts in a manner that can account for a number of interlinked factors in the control room environment. In particular, we describe a cognitive operator/plant model that serves as a framework for integrating the operator`s information-processing capabilities with his procedural knowledge, to provide insight as to how situations are assessed by the operator, decisions made, procedures executed, and communications conducted. Our focus is on the situation assessment (SA) behavior of the operator, the development of a quantitative metric reflecting overall operator awareness, and the use of this metric in evaluating automation/aiding options. We describe the results of a model-based simulation of a selected emergency scenario, and metric-based evaluation of a range of contemplated NPP control room automation/aiding options. The results demonstrate the feasibility of model-based analysis of contemplated control room enhancements, and highlight the need for empirical validation.

Varenna workshop report. Operational earthquake forecasting and decision making

Directory of Open Access Journals (Sweden)

Warner Marzocchi

2015-09-01

Full Text Available A workshop on Operational earthquake forecasting and decision making was convened in Varenna, Italy, on June 8-11, 2014, under the sponsorship of the EU FP 7 REAKT (Strategies and tools for Real-time EArthquake risK reducTion project, the Seismic Hazard Center at the Istituto Nazionale di Geofisica e Vulcanologia (INGV, and the Southern California Earthquake Center (SCEC. The main goal was to survey the interdisciplinary issues of operational earthquake forecasting (OEF, including the problems that OEF raises for decision making and risk communication. The workshop was attended by 64 researchers from universities, research centers, and governmental institutions in 11 countries. Participants and the workshop agenda are listed in the appendix.The workshop comprised six topical sessions structured around three main themes: the science of operational earthquake forecasting, decision making in a low-probability environment, and communicating hazard and risk. Each topic was introduced by a moderator and surveyed by a few invited speakers, who were then empaneled for an open discussion. The presentations were followed by poster sessions. During a wrap-up session on the last day, the reporters for each topical session summarized the main points that they had gleaned from the talks and open discussions. This report attempts to distill this workshop record into a brief overview of the workshop themes and to describe the range of opinions expressed during the discussions.

Role of conceptual models in nuclear power plant operation

International Nuclear Information System (INIS)

Williams, M.D.; Moran, T.P.; Brown, J.S.

1982-01-01

A crucial objective in plant operation (and perhaps licensing) ought to be to explicitly train operators to develop, perhaps with computer aids, robust conceptual models of the plants they control. The question is whether we are actually able to develop robust conceptual models and validate their robustness. Cognitive science is just beginning to come to grips with this problem. This paper describes some of the evolving technology for building conceptual models of physical mechanisms and some of the implications of such models in the context of nuclear power plant operation

Dissecting Attending Surgeons' Operating Room Guidance: Factors That Affect Guidance Decision Making.

Science.gov (United States)

Chen, Xiaodong Phoenix; Williams, Reed G; Smink, Douglas S

2015-01-01

The amount of guidance provided by the attending surgeon in the operating room (OR) is a key element in developing residents' autonomy. The purpose of this study is to explore factors that affect attending surgeons' decision making regarding OR guidance provided to the resident. We used video-stimulated recall interviews (VSRI) throughout this 2-phase study. In Phase 1, 3 attending surgeons were invited to review separately 30 to 45 minute video segments of their prerecorded surgical operations to explore factors that influenced their OR guidance decision making. In Phase 2, 3 attending surgeons were observed and documented in the OR (4 operations, 341min). Each operating surgeon reviewed their videotaped surgical performance within 5 days of the operation to reflect on factors that affected their decision making during the targeted guidance events. All VSRI were recorded. Thematic analysis and manual coding were used to synthesize and analyze data from VSRI transcripts, OR observation documents, and field notes. A total of 255 minutes of VSRI involving 6 surgeons and 7 surgical operations from 5 different procedures were conducted. A total of 13 guidance decision-making influence factors from 4 categories were identified (Cohen's κ = 0.674): Setting (case schedule and patient morbidity), content (procedure attributes and case progress), resident (current competency level, trustworthiness, self-confidence, and personal traits), and attending surgeon (level of experience, level of comfort, preferred surgical technique, OR training philosophy, and responsibility as surgeon). A total of 5 factors (case schedule, patient morbidity, procedure attributes, resident current competency level, and trustworthiness) influenced attending surgeons' pre-OR guidance plans. "OR training philosophy" and "responsibility as surgeon" were anchor factors that affected attending surgeons' OR guidance decision-making patterns. Surgeons' OR guidance decision making is a dynamic process

Advanced maintenance strategies for power plant operators--introducing inter-plant life cycle management

International Nuclear Information System (INIS)

Graeber, Ulrich

2004-01-01

One of the most important goals of competing power plant operators is to ensure safe operation of their plants, characterized by maximum availability throughout the entire life cycle and minimized specific generating costs. One parameter crucial to the total price of electricity--and one that can be actively influenced by the power plant operators--is maintenance. Up to 30% of all electricity generating costs accrue from maintenance. In the past years maintenance measures have been optimized particularly by the application and continuing development of testing and diagnostic techniques, by the increased level of system and component automation as well as more efficient organization structures. Despite the considerable success of these efforts, the potential for further cost reductions is still far from exhausted. But the risks connected to reliability, availability and safety need to be analyzed in greater detail in order to ensure the sustainability of the savings already achieved as well as those yet to be realized. The systematic application of condition-based maintenance and the implementation of structured life cycle management are essential requirements. An inter-plant approach is recommended to make a quick implementation of maintenance optimization potentials possible. Plant-specific improvement potentials can be established with the help of a best-practice comparison, and measures and priorities can be defined for realizing them. Creating an inter-plant database will allow experience and findings to be analyzed quickly and efficiently by experts and made available to all participants on a neutral platform. Despite--or maybe owing to--the increasingly competitive marketplace, a sustained reduction in the maintenance costs of power plant operators can only be achieved through a structured, inter-plant exchange of experience. The ZES offers the industry a suitable platform for cooperation with its 'Condition-Based Maintenance' research focus. The introduction

Operation of Finnish nuclear power plants

International Nuclear Information System (INIS)

Tossavainen, K.

1994-03-01

In the third quarter of 1993, all of Finland's four nuclear power plant units were in power operation, with the exception of the annual maintenance outages of the Loviisa units. The load factor average of the plant units was 83.6 %. None of the events which occurred during this annual quarter had any bearing on nuclear or radiation safety. (4 figs., 5 tabs.)

20 years' operation of the Rheinsberg nuclear power plant

International Nuclear Information System (INIS)

Lehmann, R.; Quasniczka, H.; Fiss, W.; Hentschel, G.; Schulz, K.D.

1986-01-01

After a 20 years' operation of the Rheinsberg nuclear power plant a review of the operating results achieved, performance of the main equipment, research and development works performed, and experience gained with education and training of plant staff is given. (author)

Requirements and Possibilities for Operational Experience Feedback from the Plant's Manufacturer's Point of View

International Nuclear Information System (INIS)

Schimann, P.

2010-01-01

A large amount of nations has realized that nuclear energy can contribute sustainable to secure their national energy supply. In the last few years, apart from the established nuclear nations, other, often smaller countries have also decided for themselves to apply the nuclear option to secure their energy supply. This partly takes place in multi-national cooperation between neighboring countries on one side, as well as otherwise between different companies on the manufacturers'/utilities' side. The endeavor of building absolutely safe reactors and of operating them safely requires the necessity on different levels of considering existing and up to date experiences gained in all the nuclear projects' phases. The long time period of many years between the decision on building a nuclear power plant, the licensing procedure, the detailed planning, the construction phase and the commissioning of the plants, results in the necessity of having to incorporate the constant experience gain on all technical and administrative levels. This applies to the safety-related boundary conditions in the frame of a new-build project in the same way as for updating measures performed on existing plants. An often neglected fact, this also applies to the right choice of the guidelines to be applied, to an efficient and competent authority and utility body or to the integration of the appropriate technical specialists and experts. Therefore the utilities and their tasks are confronted with different requirements, depending on whether they are located in the country of responsible nuclear power plant utilities' head quarters or whether they are simply co-owners of a foreign plant. AREVA as company covering the complete nuclear cycle including the corresponding plant construction supports its partners in all project phases including the development of national institutions and knowledge transfer. All of AREVA's existing knowledge - even the recently obtained - is integrated directly in the

Use of computer codes to improve nuclear power plant operation

International Nuclear Information System (INIS)

Misak, J.; Polak, V.; Filo, J.; Gatas, J.

1985-01-01

For safety and economic reasons, the scope for carrying out experiments on operational nuclear power plants (NPPs) is very limited and any changes in technical equipment and operating parameters or conditions have to be supported by theoretical calculations. In the Nuclear Power Plant Scientific Research Institute (NIIAEhS), computer codes are systematically used to analyse actual operating events, assess safety aspects of changes in equipment and operating conditions, optimize the conditions, preparation and analysis of NPP startup trials and review and amend operating instructions. In addition, calculation codes are gradually being introduced into power plant computer systems to perform real time processing of the parameters being measured. The paper describes a number of specific examples of the use of calculation codes for the thermohydraulic analysis of operating and accident conditions aimed at improving the operation of WWER-440 units at the Jaslovske Bohunice V-1 and V-2 nuclear power plants. These examples confirm that computer calculations are an effective way of solving operating problems and of further increasing the level of safety and economic efficiency of NPP operation. (author)

Nuclear units operating improvement by using operating experience

International Nuclear Information System (INIS)

Rotaru, I.; Bilegan, I.C.

1997-01-01

The paper presents how the information experience can be used to improve the operation of nuclear units. This areas include the following items: conservative decision making; supervisory oversight; teamwork; control room distraction; communications; expectations and standards; operator training and fundamental knowledge, procedure quality and adherence; plant status awareness. For each of these topics, the information illustrate which are the principles, the lessons learned from operating experience and the most appropriate exemplifying documents. (authors)

Application of grey theory in operator management

International Nuclear Information System (INIS)

Xu Hong

2013-01-01

Scientific and reasonable operator management is the basis of nuclear safety. It is paid more attention after the three-mile island accident. The prediction of operators' basic behavior parameters is the premise and foundation of scientific and reasonable operator management. Grey theory happened to solve the dilemma encountered in prediction and decision-making of operator behavior in operator management of nuclear power plant. The procedure was divided into two steps: 1) According to the historical record of operators' behavior parameters, a differential equation model using grey theory was set up to predict the future behavior of operators; 2) operator management decision-making was made based on grey theory. The calculation result is not only helpful for operator management but also useful for operators to find their shortcomings. Grey theory used in the study provides a new idea and method for future operator management in nuclear power plant. (author)

Operating-procedure system at Savannah River Plant

International Nuclear Information System (INIS)

Tope, C.W.

1981-05-01

Three types of procedures are widely used at SRP: Du Pont Savannah Operating Logsheet, Du Pont Savannah Operating Procedure, and Plant Manual. This document briefly reviews originating of the procedures, their preparation, control, and indexing

Training and qualification of nuclear power plant operators

International Nuclear Information System (INIS)

Ohsuga, Y.

2008-01-01

Based on training experiences of the nuclear power plant operators of pressurized water reactors (PWR) at the Nuclear Power Training Center Ltd. (NTC) in Japan, training programs were reviewed referring to US training programs. A systematic approach is deployed to them, which mainly consist of on-the-job training and the NTC training courses to meet the needs of all operators from beginners to experienced veterans according to their experiences and objectives. The NTC training is conducted using the simulators that simulate the nuclear power plant dynamics through the use of computers. The operators trained at the NTC work in the central control room of every PWR power plant. The NTC also carries out the qualification examinations for the shift managers. (T. Tanaka)

Reliability research to nuclear power plant operators based on several methods

International Nuclear Information System (INIS)

Fang Xiang; Li Fu; Zhao Bingquan

2009-01-01

The paper utilizes many kinds of international reliability research methods, and summarizes the review of reliability research of Chinese nuclear power plant operators in past over ten years based on the simulator platform of nuclear power plant. The paper shows the necessity and feasibility of the research to nuclear power plant operators from many angles including human cognition reliability, fuzzy mathematics model and psychological research model, etc. It will be good to the safe operation of nuclear power plant based on many kinds of research methods to the reliability research of nuclear power plant operators. (authors)

A methodology for nuclear power plant operational events evaluation

International Nuclear Information System (INIS)

Araujo, Jeferson

2015-01-01

Operational events are normal occurrences in industrial plants and in nuclear power plants. The evaluation of operational events gains importance when it comes specifically to nuclear power plants due to the proportions that the impact and the consequences of these events may cause to the installation itself, their workers, the external area of the nuclear installation, the environment and to the public in general. These consequences, for the operation of these facilities can range from very little, until the consequences that lead to accidents and can cause significant impacts. Operational events may be associated or have influence in many fields of knowledge, such as operation, maintenance, engineering, Radiological Protection, physical protection, chemistry, Human or Organizational Factors and external events, among others. The accident at the Fukushima Daichi nuclear power plant, shows the importance of exhausting all the studies concerning operational events in order to improve the operational safety of nuclear plants, considering all the causes and possible consequences. In this context, the evaluation of operational events discipline emerges as an important and relevant tool to contribute to the maintenance and/or improvement of the operational safety of nuclear installations. Not without reason the nuclear industry actively participates in programs of exchange of operational experience, where relevant events are thoroughly evaluated and discussed in specific forums, such as power plant operators, regulators and/or joint technical meetings, always with the purpose to prevent, minimize or mitigate its consequences. Any evaluation of operational events passes necessarily by an in-depth study of the circumstances of the event, culminating with the identification of your cause and proposition of corrective actions to prevent recurrence of similar events. Additionally, the events should not be studied individually, but evaluated within a temporal context in order

A methodology for nuclear power plant operational events evaluation

Energy Technology Data Exchange (ETDEWEB)

Araujo, Jeferson, E-mail: jeferson@cnen.gov.br [Comissao Nacional de Energia Nuclear (CGRC/CNEN), Rio de janeiro, RJ (Brazil). Coordenacao Geral de Reatores e do Ciclo de Combustivel; Costa, Sergio Dias, E-mail: sergiodiascosta@hotmail.com [Instituto de Engenharia Nuclear (IEN/CNEN-RJ), Rio de Janeiro, RJ (Brazil)

2015-07-01

Operational events are normal occurrences in industrial plants and in nuclear power plants. The evaluation of operational events gains importance when it comes specifically to nuclear power plants due to the proportions that the impact and the consequences of these events may cause to the installation itself, their workers, the external area of the nuclear installation, the environment and to the public in general. These consequences, for the operation of these facilities can range from very little, until the consequences that lead to accidents and can cause significant impacts. Operational events may be associated or have influence in many fields of knowledge, such as operation, maintenance, engineering, Radiological Protection, physical protection, chemistry, Human or Organizational Factors and external events, among others. The accident at the Fukushima Daichi nuclear power plant, shows the importance of exhausting all the studies concerning operational events in order to improve the operational safety of nuclear plants, considering all the causes and possible consequences. In this context, the evaluation of operational events discipline emerges as an important and relevant tool to contribute to the maintenance and/or improvement of the operational safety of nuclear installations. Not without reason the nuclear industry actively participates in programs of exchange of operational experience, where relevant events are thoroughly evaluated and discussed in specific forums, such as power plant operators, regulators and/or joint technical meetings, always with the purpose to prevent, minimize or mitigate its consequences. Any evaluation of operational events passes necessarily by an in-depth study of the circumstances of the event, culminating with the identification of your cause and proposition of corrective actions to prevent recurrence of similar events. Additionally, the events should not be studied individually, but evaluated within a temporal context in order

Use of Human Reliability Insights to Improve Decision-Making

International Nuclear Information System (INIS)

Julius, J. A.; Moieni, P.; Grobbelaar, J.; Kohlhepp, K.

2016-01-01

This paper describes the use of insights obtained during the development and application of human reliability analysis (HRA) as part of a probabilistic risk assessment (PRA) to support decision-making, including improvements to operations, training, and safety culture. Insights have been gained from the development and application of HRA as part of a PRA for nuclear power plants in the USA, Europe and Asia over the last two decades. These models consist of Level 1 and Level 2 PRA models of internal and external events, during full power and shutdown modes of plant operation. These insights include the use of human factors information to improve the qualitative portion of the HRA. The subsequent quantification in the HRA effectively prioritises the contributors to the unreliability of operator actions, and the process facilitates the identification of the factors that are important to the success of the operator actions. Additionally, the tools and techniques also allow for the evaluation of key assumptions and sources of uncertainty. The end results have been used to effectively support decision-making for day-to-day plant operations as well as licensing issues. HRA results have been used to provide feedback and improvements to plant procedures, operator training and other areas contributing the plant safety culture. Examples of the types of insights are presented in this paper. (author)