WorldWideScience

Sample records for nuclear events contingency

  1. Contingency Analysis of Cascading Line Outage Events

    Energy Technology Data Exchange (ETDEWEB)

    Thomas L Baldwin; Magdy S Tawfik; Miles McQueen

    2011-03-01

    As the US power systems continue to increase in size and complexity, including the growth of smart grids, larger blackouts due to cascading outages become more likely. Grid congestion is often associated with a cascading collapse leading to a major blackout. Such a collapse is characterized by a self-sustaining sequence of line outages followed by a topology breakup of the network. This paper addresses the implementation and testing of a process for N-k contingency analysis and sequential cascading outage simulation in order to identify potential cascading modes. A modeling approach described in this paper offers a unique capability to identify initiating events that may lead to cascading outages. It predicts the development of cascading events by identifying and visualizing potential cascading tiers. The proposed approach was implemented using a 328-bus simplified SERC power system network. The results of the study indicate that initiating events and possible cascading chains may be identified, ranked and visualized. This approach may be used to improve the reliability of a transmission grid and reduce its vulnerability to cascading outages.

  2. 75 FR 64717 - Convention on Supplementary Compensation for Nuclear Damage Contingent Cost Allocation

    Science.gov (United States)

    2010-10-20

    ... DEPARTMENT OF ENERGY Convention on Supplementary Compensation for Nuclear Damage Contingent Cost... Supplementary Compensation for Nuclear Damage (``CSC'') including its obligation to contribute to an international supplementary fund in the event of certain nuclear incidents. The NOI provided a September 27...

  3. Public education programme for nuclear contingency planning in Hong Kong

    International Nuclear Information System (INIS)

    Wong, M. C.; Li, S. W.

    2002-01-01

    Two nuclear power stations on the coast of southern China are situated some 50 kilometers to the northeast of Hong Kong. Although the stations are far away from Hong Kong, the construction and operation of the nuclear power stations have generated public anxiety locally, in particular, after the Chernobyl accident in 1986. A comprehensive contingency plan which takes into account such concerns of the public has been implemented in Hong Kong. Cooperation by the public is vital to the effective implementation of any contingency plan. Understanding of the basics of radiation protection as well as the contingency plan will help the public to appreciate the situation and react in a rational manner. A public education program to promote awareness of the contingency plan has been implemented in Hong Kong. In particular, a Virtual Exhibition Hall on radiation has been developed and launched in February 2002 for access by the public via Internet. A video and a set of web pages will be launched in the later part of 2002 to inform and educate the public on matters related to nuclear accident response in Hong Kong. This paper describes the public education programme in Hong Kong to promote public awareness and understanding of the nuclear contingency plan

  4. The Chalk River Nuclear Laboratories contingency plan -a brief description

    International Nuclear Information System (INIS)

    White, J.M.

    1982-01-01

    A brief description of the contingency plan which deals with both the on-site and off-site consequences of a serious nuclear accident is given. The off-site consequences of different size releases and the subsequent action taken by employees, radiation protection experts, municipal, Provincial and Federal authorities is described and the interaction of the various groups is discussed. (author)

  5. Contingency planning in southern Africa: Events rather than processes?

    OpenAIRE

    Elias Mabaso; Siambabala B. Manyena

    2013-01-01

    With the increasing frequency, magnitude and impact of disasters, there is growing focus on contingency planning as a tool for enhancing resilience. Yet, there is little empirical evidence that reflects on the practice of contingency planning systems within the context of disaster risk reduction. This article explores the practice of contingency planning in southern Africa, focussing on Malawi, Mozambique, Namibia, Zambia and Zimbabwe. A qualitative comparative analysis informed by fieldwork ...

  6. Contingency planning for nuclear emergencies in Hong Kong

    International Nuclear Information System (INIS)

    Wong, M. C.

    2002-01-01

    Two nuclear power stations on the coast of southern China are situated some 50 kilometers to the northeast of Hong Kong. Although the stations are far away from Hong Kong, the construction and operation of the nuclear power stations have generated public anxiety locally, in particular, after the Chernobyl accident in 1986. A comprehensive contingency plan which takes into account such concerns of the public has been implemented in Hong Kong. This plan not only aims to ensure a quick and timely response to mitigate the health impact of any accidental release but also targets to re-assure the public that the territory is not contaminated when appropriate. This paper describes the principal elements of the nuclear contingency plan in Hong Kong, namely, an extensive environmental radiation monitoring programme and a proactive public communication programme

  7. Contingency planning in southern Africa: Events rather than processes?

    Directory of Open Access Journals (Sweden)

    Elias Mabaso

    2013-09-01

    Full Text Available With the increasing frequency, magnitude and impact of disasters, there is growing focus on contingency planning as a tool for enhancing resilience. Yet, there is little empirical evidence that reflects on the practice of contingency planning systems within the context of disaster risk reduction. This article explores the practice of contingency planning in southern Africa, focussing on Malawi, Mozambique, Namibia, Zambia and Zimbabwe. A qualitative comparative analysis informed by fieldwork was used. The findings show that (1 there was a wide gap between theory and practice in contingency planning, (2 response activities rarely reflected projected scenarios and (3 resources were inadequate for effective contingency planning. We conclude that unless these issues are addressed, contingency planning is likely to remain a theoretical rather than a practical tool for building disaster-resilient communities in southern African countries. Although a generalisation cannot be made on the status of contingency planning and practice in southern Africa without a wider analysis of more examples, the findings may apply beyond the examined contexts and also offer insights into research gaps.

  8. Contingent Attentional Capture by Top-Down Control Settings: Converging Evidence from Event-Related Potentials

    Science.gov (United States)

    Lien, Mei-Ching; Ruthruff, Eric; Goodin, Zachary; Remington, Roger W.

    2008-01-01

    Theories of attentional control are divided over whether the capture of spatial attention depends primarily on stimulus salience or is contingent on attentional control settings induced by task demands. The authors addressed this issue using the N2-posterior-contralateral (N2pc) effect, a component of the event-related brain potential thought to…

  9. Licensee safeguards contingency plans

    International Nuclear Information System (INIS)

    Anon.

    1978-01-01

    The Nuclear Regulatory Commission is amending its regulations to require that licensees authorized to operate a nuclear reactor (other than certain research and test reactors), and those authorized to possess strategic quantities of plutonium, uranium-233, or uranium-235 develop and implement acceptable plans for responding to threats, thefts, and industrial sabotage of licensed nuclear materials and facilities. The plans will provide a structured, orderly, and timely response to safeguards contingencies and will be an important segment of NRC's contingency planning programs. Licensee safeguards contingency plans will result in organizing licensee's safeguards resources in such a way that, in the unlikely event of a safeguards contingency, the responding participants will be identified, their several responsibilities specified, and their responses coordinated

  10. Counterfactual reasoning for regretted situations involving controllable versus uncontrollable events: the modulating role of contingent self-esteem.

    Science.gov (United States)

    Wilkinson, Meredith R; Ball, Linden J; Alford, David

    2015-01-01

    We report a study that examined the modulating impact of contingent self-esteem on regret intensity for regretted outcomes associated with controllable versus uncontrollable events. The Contingent Self-Esteem Scale (e.g., Kernis & Goldman, 2006) was used to assess the extent to which a person's sense of self-worth is based on self and others' expectations. We found that there was an influence of self-esteem contingency for controllable but not for uncontrollable regret types. For controllable regret types individuals with a high contingent (i.e., unstable) self-esteem reported greater regret intensity than those with a low contingent (i.e., stable) self-esteem. We interpret this finding as reflecting a functional and adaptive role of high contingent self-esteem in terms of mobilizing the application of counterfactual reasoning and planning mechanisms that can enable personal expectations to be achieved in the future.

  11. Counterfactual Reasoning for Regretted Situations Involving Controllable Versus Uncontrollable Events: The Modulating Role of Contingent Self-Esteem

    Science.gov (United States)

    Wilkinson, Meredith R.; Ball, Linden J.; Alford, David

    2015-01-01

    We report a study that examined the modulating impact of contingent self-esteem on regret intensity for regretted outcomes associated with controllable versus uncontrollable events. The Contingent Self-Esteem Scale (e.g., Kernis & Goldman, 2006) was used to assess the extent to which a person’s sense of self-worth is based on self and others’ expectations. We found that there was an influence of self-esteem contingency for controllable but not for uncontrollable regret types. For controllable regret types individuals with a high contingent (i.e., unstable) self-esteem reported greater regret intensity than those with a low contingent (i.e., stable) self-esteem. We interpret this finding as reflecting a functional and adaptive role of high contingent self-esteem in terms of mobilizing the application of counterfactual reasoning and planning mechanisms that can enable personal expectations to be achieved in the future. PMID:25883697

  12. Potential Russian Nuclear Contingencies in the Caucasus: Implications for NATO

    National Research Council Canada - National Science Library

    Wagner, Thomas

    2000-01-01

    ...; and a conflict involving Turkey. The Caucasus is the region in which it is most plausible that Russia might resort to nuclear weapons in extreme circumstances This region has been in turmoil since the collapse of the Soviet Union...

  13. Evaluating the public perceptions of nuclear power in China: Evidence from a contingent valuation survey

    International Nuclear Information System (INIS)

    Sun, Chuanwang; Zhu, Xiting

    2014-01-01

    After the Fukushima nuclear accident, more and more attention has been paid to the safety issues of nuclear power in China, even though it is a clean and necessary substitution to coal power. Due to the consideration about the uncertainty of nuclear safety, the local citizens may resist the nuclear power programs in their neighborhood, as indicated by the anti-nuclear movement in Jiangmen 2013. This phenomenon is often related to the public perceptions of “not-in-my-back-yard” (NIMABY). The explosion of anti-nuclear movements will impose adverse effects on the nuclear power decision-making in China. Based on the Contingent Valuation Method (CVM), we evaluate the public Willingness-To-Pay (WTP) for avoiding the construction of nuclear power plants in their neighborhood. Moreover, we analyze whether more information about nuclear energy could improve the public acceptance. Our results show that the comprehensive information will decrease the public risk perception of nuclear power and increase the public support for nuclear power policy. This paper further suggests that China's decision makers should improve policy transparency and encourage the public involvement of nuclear energy decision making. - Highlights: • We firstly evaluate the WTP for avoiding nuclear construction in China. • The study is based on the CV survey data after the Fukushima accident. • More understanding of nuclear energy could improve public acceptance. • Decision-makers should improve policy transparency and public involvement

  14. Measuring the social value of nuclear energy using contingent valuation methodology

    International Nuclear Information System (INIS)

    Jun, Eunju; Joon Kim, Won; Hoon Jeong, Yong; Heung Chang, Soon

    2010-01-01

    As one of the promising energy sources for the next few decades, nuclear energy receives more attention than before as environmental issues become more important and the supply of fossil fuels becomes unstable. One of the reasons for this attention is based on the rapid innovation of nuclear technology which solves many of its technological constraints and safety issues. However, regardless of these rapid innovations, social acceptance for nuclear energy has been relatively low and unchanged. Consequently, the social perception has often been an obstacle to the development and execution of nuclear policy requiring enormous subsidies which are not based on the social value of nuclear energy. Therefore, in this study, we estimate the social value of nuclear energy-consumers' willingness-to-pay for nuclear energy-using the Contingent Valuation Method (CVM) and suggest that the social value of nuclear energy increases approximately 68.5% with the provision of adequate information about nuclear energy to the public. Consequently, we suggest that the social acceptance management in nuclear policy development is important along with nuclear technology innovation.

  15. Assessing Energy Intake in Daily Life: Signal-Contingent Smartphone Application Versus Event-Contingent Paper and Pencil Estimated Diet Diary

    Directory of Open Access Journals (Sweden)

    Saskia Wouters

    2016-12-01

    Full Text Available Objectives: Investigating between-meal snack intake and its associated determinants such as emotions and stress presents challenges because both vary from moment to moment throughout the day. A smartphone application (app, was developed to map momentary between-meal snack intake and its associated determinants in the context of daily life. The aim of this study was to compare energy intake reported with the signal-contingent app and reported with an event-contingent paper and pencil diet diary. Methods: In a counterbalanced, cross-sectional design, adults (N = 46 from the general population reported between-meal snack intake during four consecutive days with the app and four consecutive days with a paper and pencil diet diary. A 10-day interval was applied between the two reporting periods. Multilevel regression analyses were conducted to compare both instruments on reported momentary and daily energy intake from snacks.  Results: Results showed no significant difference (B = 11.84, p = .14 in momentary energy intake from snacks between the two instruments. However, a significant difference (B = –105.89, p < .01 was found on energy intake from total daily snack consumption. Conclusions: As at momentary level both instruments were comparable in assessing energy intake, research purposes will largely determine the sampling procedure of choice. When momentary associations across time are the interest of study, a signal-contingent sampling procedure may be a suitable method. Since the compared instruments differed on two main features (i.e. the sampling procedure and the device used it is difficult to disentangle which instrument was the most accurate in assessing daily energy intake.

  16. A methodology to assist in contingency planning for protection of nuclear power plants against land vehicle bombs

    International Nuclear Information System (INIS)

    James, J.W.; Goldman, L.A.; Lobner, P.R.; Finn, S.P.; Koch, T.H.; Veatch, J.D.

    1989-04-01

    This report provides a methodology which could be used by operators of licensed nuclear power reactors to address issues related to contingency planning for a land vehicle bomb, should such a threat arise. The methodology presented in this report provides a structured framework for understanding factors to be considered in contingency planning for a land vehicle bomb including: (1) system options available to maintain a safe condition, (2) associated components and equipment, (3) preferred system options for establishing and maintaining a safe shutdown condition, and (4) contingency measures to preserve the preferred system options. Example applications of the methodology for a Boiling Water Reactor (BWR) and Pressurized Water Reactor (PWR) are provided along with an example of contingency plan changes necessary for implementation of this methodology, a discussion of some contingency measures that can be used to limit land vehicle access, and a bibliography. 2 refs., 11 figs., 6 tabs

  17. Rats distinguish between absence of events and lack of evidence in contingency learning.

    Science.gov (United States)

    Waldmann, Michael R; Schmid, Martina; Wong, Jared; Blaisdell, Aaron P

    2012-09-01

    The goal of three experiments was to study whether rats are aware of the difference between absence of events and lack of evidence. We used a Pavlovian extinction paradigm in which lights consistently signaling sucrose were suddenly paired with the absence of sucrose. The crucial manipulation involved the absent outcomes in the extinction phase. Whereas in the Cover conditions, access to the drinking receptacle was blocked by a metal plate, in the No Cover conditions, the drinking receptacle was accessible. The Test phase showed that in the Cover conditions, the measured expectancies of sucrose were clearly at a higher level than in the No Cover conditions. We compare two competing theories potentially explaining the findings. A cognitive theory interprets the observed effect as evidence that the rats were able to understand that the cover blocked informational access to the outcome information, and therefore the changed learning input did not necessarily signify a change of the underlying contingency in the world. An alternative associationist account, renewal theory, might instead explain the relative sparing of extinction in the Cover condition as a consequence of context change. We discuss the merits of both theories as accounts of our data and conclude that the cognitive explanation is in this case preferred.

  18. International scaling of nuclear and radiological events

    International Nuclear Information System (INIS)

    Wang Yuhui; Wang Haidan

    2014-01-01

    Scales are inherent forms of measurement used in daily life, just like Celsius or Fahrenheit scales for temperature and Richter for scale for earthquakes. Jointly developed by the IAEA and OECD/NEA in 1990, the purpose of International Nuclear and Radiological Event Scale (INES) is to help nuclear and radiation safety authorities and the nuclear industry worldwide to rate nuclear and radiological events and to communicate their safety significance to the general public, the media and the technical community. INES was initially used to classify events at nuclear power plants only. It was subsequently extended to rate events associated with the transport, storage and use of radioactive material and radiation sources, from those occurring at nuclear facilities to those associated with industrial use. Since its inception, it has been adopted in 69 countries. Events are classified on the scale at seven levels: Levels 1-3 are called 'incidents' and Levels 4-7 'accidents'. The scale is designed so that the severity of an event is about ten times greater for each increase in level on the scale. Events without safety significance are called 'deviations' and are classified Below Scale/Level 0. INES classifies nuclear and radiological accidents and incidents by considering three areas of impact: People and the Environment; Radiological Barriers and Control; Defence-in-Depth. By now, two nuclear accidents were on the highest level of the scale: Chernobyl and Fukumashi. (authors)

  19. Trends and characteristics observed in nuclear events based on international nuclear event scale reports

    International Nuclear Information System (INIS)

    Watanabe, Norio

    2001-01-01

    The International Nuclear Event Scale (INES) is jointly operated by the IAEA and the OECD-NEA as a means designed for providing prompt, clear and consistent information related to nuclear events, that occurred at nuclear facilities, and facilitating communication between the nuclear community, the media and the public. Nuclear events are reported to the INES with the Scale', a consistent safety significance indicator, which runs from level 0, for events with no safety significance, to level 7 for a major accident with widespread health and environmental effects. Since the operation of INES was initiated in 1990, approximately 500 events have been reported and disseminated. The present paper discusses the trends observed in nuclear events, such as overall trends of the reported events and characteristics of safety significant events with level 2 or higher, based on the INES reports. (author)

  20. Power system security enhancement with unified power flow controller under multi-event contingency conditions

    Directory of Open Access Journals (Sweden)

    S. Ravindra

    2017-03-01

    Full Text Available Power system security analysis plays key role in enhancing the system security and to avoid the system collapse condition. In this paper, a novel severity function is formulated using transmission line loadings and bus voltage magnitude deviations. The proposed severity function and generation fuel cost objectives are analyzed under transmission line(s and/or generator(s contingency conditions. The system security under contingency conditions is analyzed using optimal power flow problem. An improved teaching learning based optimization (ITLBO algorithm has been presented. To enhance the system security under contingency conditions in the presence of unified power flow controller (UPFC, it is necessary to identify an optimal location to install this device. Voltage source based power injection model of UPFC, incorporation procedure and optimal location identification strategy based on line overload sensitivity indexes are proposed. The entire proposed methodology is tested on standard IEEE-30 bus test system with supporting numerical and graphical results.

  1. Measuring the Social Value of Nuclear Energy using Contingent Valuation Methodology

    International Nuclear Information System (INIS)

    Jun, Eun Ju; Kim, Won Joon; Chang, Soon Heung

    2009-01-01

    In recent years, in addition to unstable energy supply and volatile energy prices, environmental concerns make energy security as the principal objective of energy policy in many nations. The International Energy Agency (2007) released what is probably its most pessimistic World Energy Outlook to date saying that oil and natural gas imports, coal use and greenhouse gas emissions are set to grow inexorably through 2030 - trends that threaten to undermine energy security and accelerate climate change, if countries do not change their energy use policies. In near term, nuclear is expected to be accepted as one of the promising alternatives which can achieve both energy security and prevention of climate change. However, nuclear energy has some vulnerable points in the view of social acceptance due to the history of its development and previous. Many countries which use nuclear power as one the major energy sources have been solving the problem of low social acceptance of nuclear energy by allocating enormous subsidy to local government. Korea decided to give 300 million dollar to the local government, Gyeongjoo, for constructing low level waste management facilities. Japan also paid 120 million dollar to Rokkasho-mura area for constructing nuclear waste repository. Sellarfield in England, Cabril in Spain also received subsidy every year from the related industries and their government. However these subsidies were provided without any appropriate estimation for the value of risk taking of nuclear energy. In addition, those subsidies are expected to increase and burden the central government for the further development and usage of nuclear. This study, therefore, aims to evaluate the value of nuclear energy in view of social acceptance in order to contribute to effective application for the future nuclear development and policy making. We estimate the Willingness-To-Pay of nuclear energy using Contingent Valuation Method (CVM). We find high social cost of nuclear

  2. A contingency safe, responsible, economic, increased capacity spent nuclear fuel (SNF) advance fuel cycle

    International Nuclear Information System (INIS)

    Levy, S.

    2008-01-01

    The purpose of this paper is to have an Advanced Light Water (LWR) fuel cycle and an associated development program to provide a contingency plan to the current DOE effort to license once-through spent Light Water Reactor (LWR) fuel for disposition at Yucca Mountain (YM). The intent is to fully support the forthcoming June 2008 DOE submittal to the Nuclear Regulatory Commission (NRC) based upon the latest DOE draft DOE/EIS-0250F-SID dated October 2007 which shows that the latest DOE YM doses would readily satisfy the anticipated NRC and Environmental Protection Agency (EP) standards. The proposed Advance Fuel Cycle can offer potential resolution of obstacles that might arise during the NRC review and, particularly, during the final hearings process to be held in Nevada. Another reason for the proposed concept is that a substantial capacity growth of the YM repository will be necessary to accommodate the SNF of Advance Light Water Reactors (ALWRs) currently under consideration for United States (U.S.) electricity production (1) and the results of the recently issued study by the Electric Power Research Institute (EPRI) to reduce CO 2 emissions (2). That study predicts that by 2030 U.S. nuclear power generation would grow by 64 Gigawatt electrical (GWe) and account for 25.5 percent of the overall U.S. electrical generation. The current annual SNF once-through fuel cycle accumulation would rise from 2000-2100 MT (Metric Tons) to about 3480 MT in 2030 and the total SNF inventory, would reach nearly 500,000 MT by 2100 if U. S. nuclear power continues to grow at 1.1 percent per year after 2030. That last projection does not account for any SNF reduction due to increased fuel burnup or any increased capacity needed 'to establish supply Global Nuclear Energy Partnership (GNEP,) arrangements among nations to provide nuclear fuel and taking back spent fuel for recycling without spreading enrichment and reprocessing technologies' (3). The anticipated capacity of 120 MT

  3. Safety related events at nuclear installations in 1995

    DEFF Research Database (Denmark)

    Korsbech, Uffe C C

    1996-01-01

    Nuclear safety related events of significance at least corresponding to level 2 of the International Nuclear Event Scale are described. In 1995 only two events occured at nuclear power plants, and four events occured at plants using ionizing radiation for processing or research.......Nuclear safety related events of significance at least corresponding to level 2 of the International Nuclear Event Scale are described. In 1995 only two events occured at nuclear power plants, and four events occured at plants using ionizing radiation for processing or research....

  4. Describing The Water Contingency Plan During Water Crisis in Malaysian Nuclear Agency

    International Nuclear Information System (INIS)

    Mohamad Suhaimi Yahaya; Alwi Othman; Abdul Murad Abu Bakar; Abdul Rahman Norazumin; Nazri Talib

    2015-01-01

    The status of buildings, infrastructures and radiation plants in Nuclear Malaysia are in good condition in term of water supplies. Unfortunately with the numbers of water crisis occurs recently due to shortage of treated water from SYABAS especially during hot weather had caused low water pressure and also water rationing in Selangor and Klang Valley. This event would affect the component of fire protection system and cooling system in buildings, infrastructures, reactor facility and radiation plants in Nuclear Malaysia. (author)

  5. Extreme meteorological events and nuclear facilities safety

    International Nuclear Information System (INIS)

    Almeida, Patricia Moco Princisval

    2006-01-01

    An External Event is an event that originates outside the site and whose effects on the Nuclear Power Plants (NPP) should be considered. Such events could be of natural or human induced origin and should be identified and selected for design purposes during the site evaluation process. This work shows that the subtropics and mid latitudes of South America east of the Andes Mountain Range have been recognized as prone to severe convective weather. In Brazil, the events of tornadoes are becoming frequent; however there is no institutionalized procedure for a systematic documentation of severe weather. The information is done only for some scientists and by the newspapers. Like strong wind can affect the structural integrity of buildings or the pressure differential can affect the ventilation system, our concern is the safety of NPP and for this purpose the recommendations of International Atomic Energy Agency, Nuclear Regulatory Commission and Comissao Nacional de Energia Nuclear are showed and also a data base of tornadoes in Brazil is done. (author)

  6. A Study of the Impact of Peak Demand on Increasing Vulnerability of Cascading Failures to Extreme Contingency Events

    Energy Technology Data Exchange (ETDEWEB)

    Vyakaranam, Bharat GNVSR; Vallem, Mallikarjuna R.; Nguyen, Tony B.; Samaan, Nader A.; Berscheid, Alan P.; Makarov, Yuri V.; Diao, Ruisheng

    2017-10-02

    The vulnerability of large power systems to cascading failures and major blackouts has become evident since the Northeast blackout in 1965. Based on analyses of the series of cascading blackouts in the past decade, the research community realized the urgent need to develop better methods, tools, and practices for performing cascading-outage analysis and for evaluating mitigations that are easily accessible by utility planning engineers. PNNL has developed the Dynamic Contingency Analysis Tool (DCAT) as an open-platform and publicly available methodology to help develop applications that aim to improve the capabilities of power planning engineers to assess the impact and likelihood of extreme contingencies and potential cascading events across their systems and interconnections. DCAT analysis will help identify potential vulnerabilities and allow study of mitigation solutions to reduce the risk of cascading outages in technically sound and effective ways. Using the DCAT capability, we examined the impacts of various load conditions to identify situations in which the power grid may encounter cascading outages that could lead to potential blackouts. This paper describes the usefulness of the DCAT tool and how it helps to understand potential impacts of load demand on cascading failures on the power system.

  7. Tidal Disruption Events from Eccentric Nuclear Disks

    Science.gov (United States)

    Wernke, Heather N.; Madigan, Ann-Marie

    2018-04-01

    Stars that get too close to a supermassive black hole are in danger of being tidally disrupted. Stellar two-body relaxation is commonly assumed to be the main driver of these events. Recent work has shown, however, that secular gravitational torques from eccentric nuclear disks can push stars to extreme eccentricities at much higher rates than predicted by two-body relaxation. This work did not include the effects of general relativity, however, which could quench secular torques via rapid apsidal precession. Here we show that, for a star in danger of disruption, general relativity acts on a timescale of less than an orbital period. This short timescale means that general relativity does not have enough time to have a major effect on the orbit. When driven by secular torques from eccentric nuclear disks, tidal disruption event rates are not affected by general relativity.

  8. Contingency planning for nuclear plants: an approach for use in industrial plants and hazardous products storage facilities

    Energy Technology Data Exchange (ETDEWEB)

    Carvalho, Paulo Roberto Werneck de, E-mail: paulo@pwerneck.com [Universidade Federal Fluminense (UFF), Angra dos Reis, RJ (Brazil); Hora, Antonio Ferreira da, E-mail: dahora@vm.uff.br [Universidade Federal Fluminense (UFF), Niteroi, RJ (Brazil)

    2015-07-01

    The purpose of this paper is establishing a basic system model for the development of contingency plans for emergencies. This includes the identification of agents involved in aid and assistance planning, pointing out communication chains among them, the delegation of action coordination and control, as well as the composition and structure of crisis centers equipped with physical and technological resources, the development of emergency procedures, the training of the teams involved, drill planning, and a policy for interactions with community members and the media in the course of a crisis. This paper aims at proposing actions in case an emergency affects the surroundings areas to the accident site. The outlined propositions are not to be adopted only under nuclear or radiological emergencies, since Brazil has specific legislation for this purpose, as established in the Brazilian Nuclear Program Protection System (SIPRON), in addition to the structures and contingency plans currently implemented, validated and periodically tested. (author)

  9. Contingency planning for nuclear plants: an approach for use in industrial plants and hazardous products storage facilities

    International Nuclear Information System (INIS)

    Carvalho, Paulo Roberto Werneck de; Hora, Antonio Ferreira da

    2015-01-01

    The purpose of this paper is establishing a basic system model for the development of contingency plans for emergencies. This includes the identification of agents involved in aid and assistance planning, pointing out communication chains among them, the delegation of action coordination and control, as well as the composition and structure of crisis centers equipped with physical and technological resources, the development of emergency procedures, the training of the teams involved, drill planning, and a policy for interactions with community members and the media in the course of a crisis. This paper aims at proposing actions in case an emergency affects the surroundings areas to the accident site. The outlined propositions are not to be adopted only under nuclear or radiological emergencies, since Brazil has specific legislation for this purpose, as established in the Brazilian Nuclear Program Protection System (SIPRON), in addition to the structures and contingency plans currently implemented, validated and periodically tested. (author)

  10. Application of IAEA's International Nuclear Event Scale to events at testing/research reactors in Japan

    International Nuclear Information System (INIS)

    Nozawa, Masao; Watanabe, Norio

    1999-01-01

    The International Nuclear Event Scale (INES) is a means for providing prompt, clear and consistent information related to nuclear events and facilitating communication between the nuclear community, the media and the public on such events. This paper describes the INES rating process for events at testing/research reactors and nuclear fuel processing facilities and experience on the application of the INES scale in Japan. (author)

  11. Measuring Risk Aversion for Nuclear Power Plant Accident: Results of Contingent Valuation Survey in Korea

    International Nuclear Information System (INIS)

    Lee, Sang Hun; Kang, Hyun Gook

    2015-01-01

    Within the evaluation of the external cost of nuclear energy, the estimation of the external cost of nuclear power plant (NPP) severe accident is one of the major topics to be addressed. For the evaluation of the external cost of NPP severe accident, the effect of public risk averse behavior against the group accidents, such as NPP accident, dam failure, must be addressed. Although the equivalent fatalities from a single group accident are not common and its risk is very small compared to other accidents, people perceive the group accident more seriously. In other words, people are more concerned about low probability/high consequence events than about high probability/low consequence events having the same mean damage. One of the representative method to integrate the risk aversion in the external costs of severe nuclear reactor accidents was developed by Eeckoudt et al., and he used the risk aversion coefficient, mainly based on the analysis of financial risks in the stock markets to evaluate the external cost of nuclear severe accident. However, the use of financial risk aversion coefficient to nuclear severe accidents is not appropriate, because financial risk and nuclear severe accident risk are entirely different. In this paper, the individual-level survey was conducted to measure the risk aversion coefficient and estimate the multiplication factor to integrate the risk aversion in the external costs of NPP severe accident. This study propose an integrated framework on estimation of the external cost associated with severe accidents of NPP considering public risk aversion behavior. The theoretical framework to estimate the risk aversion coefficient/multiplication factor and to assess economic damages from a hypothetical NPP accident was constructed. Based on the theoretical framework, the risk aversion coefficient can be analyzed by conducting public survey with a carefully designed lottery questions. Compared to the previous studies on estimation of the

  12. Measuring Risk Aversion for Nuclear Power Plant Accident: Results of Contingent Valuation Survey in Korea

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Sang Hun; Kang, Hyun Gook [KAIST, Daejeon (Korea, Republic of)

    2015-05-15

    Within the evaluation of the external cost of nuclear energy, the estimation of the external cost of nuclear power plant (NPP) severe accident is one of the major topics to be addressed. For the evaluation of the external cost of NPP severe accident, the effect of public risk averse behavior against the group accidents, such as NPP accident, dam failure, must be addressed. Although the equivalent fatalities from a single group accident are not common and its risk is very small compared to other accidents, people perceive the group accident more seriously. In other words, people are more concerned about low probability/high consequence events than about high probability/low consequence events having the same mean damage. One of the representative method to integrate the risk aversion in the external costs of severe nuclear reactor accidents was developed by Eeckoudt et al., and he used the risk aversion coefficient, mainly based on the analysis of financial risks in the stock markets to evaluate the external cost of nuclear severe accident. However, the use of financial risk aversion coefficient to nuclear severe accidents is not appropriate, because financial risk and nuclear severe accident risk are entirely different. In this paper, the individual-level survey was conducted to measure the risk aversion coefficient and estimate the multiplication factor to integrate the risk aversion in the external costs of NPP severe accident. This study propose an integrated framework on estimation of the external cost associated with severe accidents of NPP considering public risk aversion behavior. The theoretical framework to estimate the risk aversion coefficient/multiplication factor and to assess economic damages from a hypothetical NPP accident was constructed. Based on the theoretical framework, the risk aversion coefficient can be analyzed by conducting public survey with a carefully designed lottery questions. Compared to the previous studies on estimation of the

  13. Visits to Australia by nuclear powered or armed vessels: contingency planning for the accidental release of ionizing radiation

    International Nuclear Information System (INIS)

    1989-01-01

    The report refers to the adequacy of current contingency planning by the Australian Federal and Senate authorities to deal with the accidental release of ionizating radiation from visiting nuclear powered or armed vessels in Australian waters and ports. Much of the material was obtained in response to questions put in writing by the Senate Standing Committee to the Department of Defence, ANSTO and others. In addition, the report contains relevant information from Commonwealth documents as well as the Committee findings and recommendations. Issues considered include: types of visiting nuclear powered vessels, accident likelihood and consequences, differences between naval and land-based reactors, safety records. The persons or organizations who made submissions or appeared in all public hearings are listed in the appendixes, along with all visits to Australian ports by nuclear powered warships from 1976 to 1988

  14. Hydrologic effects of natural disruptive events on nuclear repositories

    International Nuclear Information System (INIS)

    Davis, S.N.

    1979-01-01

    This report describes some possible hydrogeologic effects of disruptive events which may affect repositories for nuclear waste. The report concentrates on the effects of natural events which are judged to be most probable

  15. Nuclear Security Systems and Measures for Major Public Events. Implementing Guide

    International Nuclear Information System (INIS)

    2012-01-01

    Terrorism remains a threat to international stability and security. High profile international and national major public events occur regularly, capturing great public interest and receiving intense media coverage. It is widely acknowledged that there is a substantial threat of a terrorist attack on major public events such as high profile political or economic summit meetings or major sporting contests. The threat of nuclear and radiological terrorism remains on the international security agenda. Nevertheless, to reduce this risk, the international community has made great progress in securing nuclear and other radioactive material that could otherwise be used in a terrorist act. This progress is contingent on the efforts of all States to adopt strong nuclear security systems and measures. There are large quantities of diverse radioactive material in existence, which are used in areas such as health, the environment, agriculture and industry. The hazards of this material vary according to composition and intensity. Additionally, the use of explosives in combination with this material can drastically enhance the impact of a criminal or terrorist act. If a criminal or terrorist group managed to detonate a so-called 'dirty' bomb in an urban area, the result could be mass panic, widespread radioactive contamination and major economic and social disruption. Major public events are seldom held in the same State or at the same location or even at the same venue. At the national level, the hosting of major public events with proper nuclear security arrangements can provide a foundation on which to build an enduring national framework for nuclear security; one that can exist long after the event. The organization of a major public event in which large numbers of people congregate presents complex security challenges for the State hosting such an event. Criminal or terrorist acts involving nuclear or other radioactive material at any major public event could result in

  16. Nuclear Security Systems and Measures for Major Public Events. Implementing Guide (Russian Edition)

    International Nuclear Information System (INIS)

    2014-01-01

    Terrorism remains a threat to international stability and security. High profile international and national major public events occur regularly, capturing great public interest and receiving intense media coverage. It is widely acknowledged that there is a substantial threat of a terrorist attack on major public events such as high profile political or economic summit meetings or major sporting contests. The threat of nuclear and radiological terrorism remains on the international security agenda. Nevertheless, to reduce this risk, the international community has made great progress in securing nuclear and other radioactive material that could otherwise be used in a terrorist act. This progress is contingent on the efforts of all States to adopt strong nuclear security systems and measures. There are large quantities of diverse radioactive material in existence, which are used in areas such as health, the environment, agriculture and industry. The hazards of this material vary according to composition and intensity. Additionally, the use of explosives in combination with this material can drastically enhance the impact of a criminal or terrorist act. If a criminal or terrorist group managed to detonate a so-called 'dirty' bomb in an urban area, the result could be mass panic, widespread radioactive contamination and major economic and social disruption. Major public events are seldom held in the same State or at the same location or even at the same venue. At the national level, the hosting of major public events with proper nuclear security arrangements can provide a foundation on which to build an enduring national framework for nuclear security; one that can exist long after the event. The organization of a major public event in which large numbers of people congregate presents complex security challenges for the State hosting such an event. Criminal or terrorist acts involving nuclear or other radioactive material at any major public event could result in

  17. Analysis of external events - Nuclear Power Plant Dukovany

    International Nuclear Information System (INIS)

    Hladky, Milan

    2000-01-01

    PSA of external events at level 1 covers internal events, floods, fires, other external events are not included yet. Shutdown PSA takes into account internal events, floods, fires, heavy load drop, other external events are not included yet. Final safety analysis report was conducted after 10 years of operation for all Dukovany operational units. Probabilistic approach was used for analysis of aircraft drop and external man-induced events. The risk caused by man-induced events was found to be negligible and was accepted by State Office for Nuclear Safety (SONS)

  18. 75 FR 43945 - Convention on Supplementary Compensation for Nuclear Damage Contingent Cost Allocation

    Science.gov (United States)

    2010-07-27

    ... of nuclear power around the world to meet the challenges of climate change, energy security, and... than power reactors having a thermal power rating of over 300 Megawatts. Also, nuclear facilities other... United States nuclear reactor operators. 934(a)(1). \\3\\ The Price-Anderson Act (``Price-Anderson'' or...

  19. Event shape analysis in ultrarelativistic nuclear collisions

    OpenAIRE

    Kopecna, Renata; Tomasik, Boris

    2016-01-01

    We present a novel method for sorting events. So far, single variables like flow vector magnitude were used for sorting events. Our approach takes into account the whole azimuthal angle distribution rather than a single variable. This method allows us to determine the good measure of the event shape, providing a multiplicity-independent insight. We discuss the advantages and disadvantages of this approach, the possible usage in femtoscopy, and other more exclusive experimental studies.

  20. Contingency planning: preparation of contingency plans

    DEFF Research Database (Denmark)

    Westergaard, J M

    2008-01-01

    . The risk of introducing disease pathogens into a country and the spread of the agent within a country depends on a number of factors including import controls, movement of animals and animal products and the biosecurity applied by livestock producers. An adequate contingency plan is an important instrument...... in the preparation for and the handling of an epidemic. The legislation of the European Union requires that all Member States draw up a contingency plan which specifies the national measures required to maintain a high level of awareness and preparedness and is to be implemented in the event of disease outbreak...

  1. Temporal contingency

    Science.gov (United States)

    Gallistel, C.R.; Craig, Andrew R.; Shahan, Timothy A.

    2015-01-01

    Contingency, and more particularly temporal contingency, has often figured in thinking about the nature of learning. However, it has never been formally defined in such a way as to make it a measure that can be applied to most animal learning protocols. We use elementary information theory to define contingency in such a way as to make it a measurable property of almost any conditioning protocol. We discuss how making it a measurable construct enables the exploration of the role of different contingencies in the acquisition and performance of classically and operantly conditioned behavior. PMID:23994260

  2. Temporal contingency.

    Science.gov (United States)

    Gallistel, C R; Craig, Andrew R; Shahan, Timothy A

    2014-01-01

    Contingency, and more particularly temporal contingency, has often figured in thinking about the nature of learning. However, it has never been formally defined in such a way as to make it a measure that can be applied to most animal learning protocols. We use elementary information theory to define contingency in such a way as to make it a measurable property of almost any conditioning protocol. We discuss how making it a measurable construct enables the exploration of the role of different contingencies in the acquisition and performance of classically and operantly conditioned behavior. Copyright © 2013 Elsevier B.V. All rights reserved.

  3. INES: The International Nuclear Event Scale user's manual

    International Nuclear Information System (INIS)

    1992-09-01

    The revised and extended addition of the International Nuclear Event Scale is presented. The manual is comprised of four parts. Part 1 contains a summary of the basis of the scale and of the procedure to be used for rating events. Part 2 contains the detailed guidance required to rate events in terms of off-site and on-site impact. These two parts are applicable to all nuclear facilities. Parts 3 and 4 contain the detailed guidance required to rate events in terms of defence in depth for reactors and other facilities, respectively. 5 figs, 2 tabs

  4. INES: The International Nuclear Event Scale. User's manual

    International Nuclear Information System (INIS)

    1990-08-01

    The International Nuclear Event Scale (INES) is being introduced for a trial period, the primary purpose being to facilitate communication between the nuclear community, the media and the public on such events. The scale runs from zero, for events with no safety significance, to seven for a major accident. The scale has been circulated to Member States of the International Atomic Energy Agency (IAEA) and the Nuclear Energy Agency of the Organisation for Economic Co-operation and Development and it is presently anticipated that the trial period will last until late 1991. Provision has been made for the scale to be refined thereafter in the light of experience. It is designed as an important tool in providing prompt, clear and consistent information on nuclear events wherever and whenever they may occur. 2 figs, 2 tabs

  5. Trend analysis of cables failure events at nuclear power plants

    International Nuclear Information System (INIS)

    Fushimi, Yasuyuki

    2007-01-01

    In this study, 152 failure events related with cables at overseas nuclear power plants are selected from Nuclear Information Database, which is owned by The Institute of Nuclear Safety System, and these events are analyzed in view of occurrence, causal factor, and so on. And 15 failure events related with cables at domestic nuclear power plants are selected from Nuclear Information Archives, which is owned by JANTI, and these events are analyzed by the same manner. As a result of comparing both trends, it is revealed following; 1) A cable insulator failure rate is lower at domestic nuclear power plants than at foreign ones. It is thought that a deterioration diagnosis is performed broadly in Japan. 2) Many buried cables failure events have been occupied a significant portion of cables failure events during work activity at overseas plants, however none has been occurred at domestic plants. It is thought that sufficient survey is conducted before excavating activity in Japan. 3) A domestic age related cables failure rate in service is lower than the overseas one and domestic improper maintenance rate is higher than the overseas one. Maintenance worker' a skill improvement is expected in order to reduce improper maintenance. (author)

  6. Indemnification of damage in the event of a nuclear accident

    International Nuclear Information System (INIS)

    2003-01-01

    The Workshop on the Indemnification of Damage in the Event of a Nuclear Accident, organised by the OECD Nuclear Energy Agency in close co-operation with the French authorities, was held in Paris from 26 to 28 November 2001. This event was an integral part of the International Nuclear Emergency Exercise INEX 2000. It attracted wide participation from national nuclear authorities, regulators, operators of nuclear installations, nuclear insurers and international organisations. The objective was to test the capacity of the existing nuclear liability and compensation mechanisms in the 29 countries represented at the workshop to manage the consequences of a nuclear emergency. This workshop was based upon the scenario used for the INEX 2000 Exercise, i.e. an accident simulated at the Gravelines nuclear power plant in the north of France in May 2001. These proceedings contain a comparative analysis of legislative and regulatory provisions governing emergency response and nuclear third party liability, based upon country replies to a questionnaire. This publication also includes the full responses provided to that questionnaire, as well as the texts of presentations made by special guests from Germany and Japan describing the manner in which the public authorities in their respective countries responded to two nuclear accidents of a very different nature and scale. (authors)

  7. The International Nuclear Event Scale (INES) user's manual. 2001 edition

    International Nuclear Information System (INIS)

    2001-12-01

    The International Nuclear Event Scale (INES) was introduced in March 1990 jointly by the International Atomic Energy Agency (IAEA) and the Nuclear Energy Agency of the Organisation for Economic Co-operation and Development (OECD/NEA). Its primary purpose is to facilitate communication and understanding between the nuclear community, the media and the public on the safety significance of events occurring at nuclear installations. The scale was refined in 1992 in the light of experience gained and extended to be applicable to any event associated with radioactive material and/or radiation, including the transport of radioactive materials.This edition of the INES User's Manual incorporates experience gained from applying the 1992 version of the scale and the document entitled 'Clarification of Issues Raised'. As such, it replaces those earlier publications. It does not amend the technical basis of the INES rating procedure but is expected to facilitate the task of those who are required to rate the safety significance of events using the INES scale. The INES communication network currently receives and disseminates event information to the INES National Officers of 60 Member States on special Event Rating Forms which represent official information on the events, including the rating. The INES communication process has led each participating country to set up an internal network which ensures that all events are promptly communicated and rated whenever they have to be reported outside or inside the country. The IAEA provides training services on the use of INES on request

  8. INES - The International Nuclear Event Scale. User's manual

    International Nuclear Information System (INIS)

    2005-01-01

    The International Nuclear Event Scale (INES) was introduced in March 1990 jointly by the International Atomic Energy Agency (IAEA) and the Nuclear Energy Agency of the Organisation for Economic Co-operation and Development (OECD/NEA). Its primary purpose is to facilitate communication and understanding between the nuclear community, the media and the public on the safety significance of events occurring at nuclear installations. The scale was refined in 1992 in the light of experience gained and extended to be applicable to any event associated with radioactive material and/or radiation, including the transport of radioactive materials. This edition of the INES User's Manual incorporates experience gained from applying the 1992 version of the scale and the document entitled 'Clarification of Issues Raised'. As such, it replaces those earlier publications. It does not amend the technical basis of the INES rating procedure but is expected to facilitate the task of those who are required to rate the safety significance of events using the INES scale. The INES communication network currently receives and disseminates event information to the INES National Officers of 60 Member States on special Event Rating Forms which represent official information on the events, including the rating. The INES communication process has led each participating country to set up an internal network which ensures that all events are promptly communicated and rated whenever they have to be reported outside or inside the country. The IAEA provides training services on the use of INES on request

  9. The International Nuclear Event Scale (INES) user's manual. 2001 edition

    International Nuclear Information System (INIS)

    2001-02-01

    The International Nuclear Event Scale (INES) was introduced in March 1990 jointly by the International Atomic Energy Agency (IAEA) and the Nuclear Energy Agency of the Organisation for Economic Co-operation and Development (OECD/NEA). Its primary purpose is to facilitate communication and understanding between the nuclear community, the media and the public on the safety significance of events occurring at nuclear installations. The scale was refined in 1992 in the light of experience gained and extended to be applicable to any event associated with radioactive material and/or radiation, including the transport of radioactive materials.This edition of the INES User's Manual incorporates experience gained from applying the 1992 version of the scale and the document entitled ''Clarification of Issues Raised''. As such, it replaces those earlier publications. It does not amend the technical basis of the INES rating procedure but is expected to facilitate the task of those who are required to rate the safety significance of events using the INES scale. The INES communication network currently receives and disseminates event information to the INES National Officers of 60 Member States on special Event Rating Forms which represent official information on the events, including the rating. The INES communication process has led each participating country to set up an internal network which ensures that all events are promptly communicated and rated whenever they have to be reported outside or inside the country. The IAEA provides training services on the use of INES on request

  10. Nuclear facility safeguards systems modeling using discrete event simulation

    International Nuclear Information System (INIS)

    Engi, D.

    1977-01-01

    The threat of theft or dispersal of special nuclear material at a nuclear facility is treated by studying the temporal relationships between adversaries having authorized access to the facility (insiders) and safeguards system events by using a GASP IV discrete event simulation. The safeguards system events--detection, assessment, delay, communications, and neutralization--are modeled for the general insider adversary strategy which includes degradation of the safeguards system elements followed by an attempt to steal or disperse special nuclear material. The performance measure used in the analysis is the estimated probability of safeguards system success in countering the adversary based upon a predetermined set of adversary actions. An exemplary problem which includes generated results is presented for a hypothetical nuclear facility. The results illustrate representative information that could be utilized by safeguards decision-makers

  11. The International Nuclear and Radiological Event Scale (INES): 20 Years of Nuclear Communication

    International Nuclear Information System (INIS)

    2010-01-01

    Full text: Today, the International Atomic Energy Agency (IAEA) and the OECD Nuclear Energy Agency (NEA) are celebrating the 20th anniversary of the International Nuclear and Radiological Event Scale (INES). Jointly developed by the IAEA and the NEA in 1990, in the aftermath of the Chernobyl accident, the purpose of INES is to help nuclear and radiation safety authorities and the nuclear industry worldwide to rate nuclear and radiological events and to communicate their safety significance to the general public, the media and the technical community. INES has often been compared to other scales used to measure physical properties such as temperature - the Celsius, Kelvin or Fahrenheit scales - or rate events such as earthquakes - the Richter scale. Like these scales, INES also has a sound technical background and can be easily understood. INES was initially used to classify events at nuclear power plants only. It was subsequently extended to rate events occurring in any nuclear facility and during the transport of radioactive material, thus also covering events related to the overexposure of workers. Since 2008, INES has been extended to any event associated with the transport, storage and use of radioactive material and radiation sources, from those occurring at nuclear facilities to those associated with industrial use. More generally, INES has also become a crucial nuclear communications tool. Since its inception, it has been adopted in 69 countries, and an increasing number of countries have expressed their interest in using INES and have designated INES national officers. Over the years, national nuclear safety authorities have made growing use of INES, while the public and the media have become more familiar with the scale and its significance. This is where the true success of INES stands, having helped to foster transparency and provide a better understanding of nuclear-related events and activities. For a full description of the International Nuclear and

  12. 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

  13. 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

  14. Simple probabilistic method for relative risk evaluation of nuclear terrorism events

    International Nuclear Information System (INIS)

    Zhang Songbai; Wu Jun

    2006-01-01

    On the basis of the event-tree and probability analysis methods, a probabilistic method of nuclear terrorism risk was built, and the risk of terrorism events was analyzed. With the statistical data for and hypothetical data for relative events, the relative probabilities of the four kinds of nuclear terrorism events were obtained, as well as the relative risks of these four kinds of nuclear terrorism events were calculated by using this probabilistic method. The illustrated case show that the descending sequence of damages from the four kinds of nuclear terrorism events for single event is as following: nuclear explosive and improvised nuclear explosive, nuclear facility attacked, and 'dirty bomb'. Under the hypothetical condition, the descending sequence of possibilities for the four kinds of nuclear terrorism events is as following: 'dirty bomb', nuclear facility attacked, improvised nuclear explosive and nuclear explosive, but the descending sequence of risks is as following: 'dirty bomb', improvised nuclear explosive, nuclear facility attacked, and nuclear explosive . (authors)

  15. A review for identification of initiating events in event tree development process on nuclear power plants

    International Nuclear Information System (INIS)

    Riyadi, Eko H.

    2014-01-01

    Initiating event is defined as any event either internal or external to the nuclear power plants (NPPs) that perturbs the steady state operation of the plant, if operating, thereby initiating an abnormal event such as transient or loss of coolant accident (LOCA) within the NPPs. These initiating events trigger sequences of events that challenge plant control and safety systems whose failure could potentially lead to core damage or large early release. Selection for initiating events consists of two steps i.e. first step, definition of possible events, such as by evaluating a comprehensive engineering, and by constructing a top level logic model. Then the second step, grouping of identified initiating event's by the safety function to be performed or combinations of systems responses. Therefore, the purpose of this paper is to discuss initiating events identification in event tree development process and to reviews other probabilistic safety assessments (PSA). The identification of initiating events also involves the past operating experience, review of other PSA, failure mode and effect analysis (FMEA), feedback from system modeling, and master logic diagram (special type of fault tree). By using the method of study for the condition of the traditional US PSA categorization in detail, could be obtained the important initiating events that are categorized into LOCA, transients and external events

  16. A review for identification of initiating events in event tree development process on nuclear power plants

    Energy Technology Data Exchange (ETDEWEB)

    Riyadi, Eko H., E-mail: e.riyadi@bapeten.go.id [Center for Regulatory Assessment of Nuclear Installation and Materials, Nuclear Energy Regulatory Agency (BAPETEN), Jl. Gajah Mada 8 Jakarta 10120 (Indonesia)

    2014-09-30

    Initiating event is defined as any event either internal or external to the nuclear power plants (NPPs) that perturbs the steady state operation of the plant, if operating, thereby initiating an abnormal event such as transient or loss of coolant accident (LOCA) within the NPPs. These initiating events trigger sequences of events that challenge plant control and safety systems whose failure could potentially lead to core damage or large early release. Selection for initiating events consists of two steps i.e. first step, definition of possible events, such as by evaluating a comprehensive engineering, and by constructing a top level logic model. Then the second step, grouping of identified initiating event's by the safety function to be performed or combinations of systems responses. Therefore, the purpose of this paper is to discuss initiating events identification in event tree development process and to reviews other probabilistic safety assessments (PSA). The identification of initiating events also involves the past operating experience, review of other PSA, failure mode and effect analysis (FMEA), feedback from system modeling, and master logic diagram (special type of fault tree). By using the method of study for the condition of the traditional US PSA categorization in detail, could be obtained the important initiating events that are categorized into LOCA, transients and external events.

  17. Nuclear target foil fabrication for the Romano Event

    International Nuclear Information System (INIS)

    Weed, J.W.; Romo, J.G. Jr.; Griggs, G.E.

    1984-01-01

    The Vacuum Processes Lab, of LLNL's M.E. Dept. - Material Fabrication Division, was requested to provide 250 coated Parylene target foils for a nuclear physics experiment titled the ROMANO Event. Due to the developmental nature of some of the fabrication procedures, approximately 400 coated foils were produced to satisfy the event's needs. The foils were used in the experiment as subkilovolt x-ray, narrow band pass filters, and wide band ultraviolet filters. This paper is divided into three sections describing: (1) nuclear target foil fabrication, (2) Parylene substrate preparation and production, and (3) foil and substrate inspections

  18. External events analysis of the Ignalina Nuclear Power Plant

    International Nuclear Information System (INIS)

    Liaukonis, Mindaugas; Augutis, Juozas

    1999-01-01

    This paper presents analysis of external events impact on the safe operation of the Ignalina Nuclear Power Plant (INPP) safety systems. Analysis was based on the probabilistic estimation and modelling of the external hazards. The screening criteria were applied to the number of external hazards. The following external events such as aircraft failure on the INPP, external flooding, fire, extreme winds requiring further bounding study were analysed. Mathematical models were developed and event probabilities were calculated. External events analysis showed rather limited external events danger to Ignalina NPP. Results of the analysis were compared to analogous analysis in western NPPs and no great differences were specified. Calculations performed show that external events can not significantly influence the safety level of the Ignalina NPP operation. (author)

  19. Assessment of the nuclear installation's safety significant events

    International Nuclear Information System (INIS)

    Vidican, D.

    2005-01-01

    This document tries to establish, based on the available documentation, the main steps in development of Assessment of the Events in Nuclear Installations. It takes into account: selection of the safety significant occurrences, establishing the direct cause and contributors as well as the root cause and contributors. Also, the document presents the necessary corrective actions and generic lessons to be learned from the event. The document is based especially on IAEA - ASSET guidelines and DOE root cause analysis Guidance. (author)

  20. Application of the international nuclear events scale in Mexico

    International Nuclear Information System (INIS)

    Ramirez, R.

    1997-01-01

    Currently in Mexico, there are two nuclear power reactors and one research reactor operating. Any event related have to be reported to the regulatory body which is in charge of the evaluation and classification using the IAEA INES system. This system has been used since its creation, process in which personnel from the regulatory body was involved. This paper describes the reporting, evaluation and classification process by which events go through with the use of the INES system

  1. Human based roots of failures in nuclear events investigations

    Energy Technology Data Exchange (ETDEWEB)

    Ziedelis, Stanislovas; Noel, Marc; Strucic, Miodrag [Commission of the European Communities, Petten (Netherlands). European Clearinghouse on Operational Experience Feedback for Nuclear Power Plants

    2012-10-15

    This paper aims for improvement of quality of the event investigations in the nuclear industry through analysis of the existing practices, identifying and removing the existing Human and Organizational Factors (HOF) and management related barriers. It presents the essential results of several studies performed by the European Clearinghouse on Operational Experience. Outcomes of studies are based on survey of currently existing event investigation practices typical for nuclear industry of 12 European countries, as well as on insights from analysis of numerous event investigation reports. System of operational experience feedback from information based on event investigation results is not enough effective to prevent and even to decrease frequency of recurring events due to existing methodological, HOF-related and/or knowledge management related constraints. Besides that, several latent root causes of unsuccessful event investigation are related to weaknesses in safety culture of personnel and managers. These weaknesses include focus on costs or schedule, political manipulation, arrogance, ignorance, entitlement and/or autocracy. Upgrades in safety culture of organization's personnel and its senior management especially seem to be an effective way to improvement. Increasing of competencies, capabilities and level of independency of event investigation teams, elaboration of comprehensive software, ensuring of positive approach, adequate support and impartiality of management could also facilitate for improvement of quality of the event investigations. (orig.)

  2. Human based roots of failures in nuclear events investigations

    International Nuclear Information System (INIS)

    Ziedelis, Stanislovas; Noel, Marc; Strucic, Miodrag

    2012-01-01

    This paper aims for improvement of quality of the event investigations in the nuclear industry through analysis of the existing practices, identifying and removing the existing Human and Organizational Factors (HOF) and management related barriers. It presents the essential results of several studies performed by the European Clearinghouse on Operational Experience. Outcomes of studies are based on survey of currently existing event investigation practices typical for nuclear industry of 12 European countries, as well as on insights from analysis of numerous event investigation reports. System of operational experience feedback from information based on event investigation results is not enough effective to prevent and even to decrease frequency of recurring events due to existing methodological, HOF-related and/or knowledge management related constraints. Besides that, several latent root causes of unsuccessful event investigation are related to weaknesses in safety culture of personnel and managers. These weaknesses include focus on costs or schedule, political manipulation, arrogance, ignorance, entitlement and/or autocracy. Upgrades in safety culture of organization's personnel and its senior management especially seem to be an effective way to improvement. Increasing of competencies, capabilities and level of independency of event investigation teams, elaboration of comprehensive software, ensuring of positive approach, adequate support and impartiality of management could also facilitate for improvement of quality of the event investigations. (orig.)

  3. External man-induced events on nuclear power plants

    International Nuclear Information System (INIS)

    Paganini, C.E.

    1982-01-01

    These notes for the postgraduate course on Radiological Protection and Nuclear Safety deal with the effects produced by some human activities on the siting and design of a nuclear installation. The existing activities, as well as the foreseen or foreseeable future ones are evaluated. In the first place, the potential sources of events are identified and classified in two categories: stationary and mobile, and the events are classified in five groups: 1) Aircraft crash; 2) Chemical explosions; 3) Discharge of dangerous fluids (explosive, toxic or corrosive); 4) Fire, and 5) Sabotage, terrorism, guerrillas. Then, the effects which may result from these events and affect the nuclear installation are studied: 1) pressure waves; 2) Impact of missiles; 3) Heat, fire; 4) Smoke and dust; 5) Gas or inflammable and/or explosive dust clouds; 6) Toxic and/or corrosive gases and liquids; 7) Ground shaking; 8) Flooding or lack of water; 9) Foundations failure or collapse. Next, the methods for making a deterministic and/or a probabilistic study (or both) are indicated for each event considered, and from these studies the ''screening'' values which allow to determine if an event can be rejected or must be considered are established. For this second case, the method for obtaining the ''design event'' that shall serve as a basis for the design of the plant is indicated. (M.E.L.) [es

  4. Stresses on nuclear power plant buildings by extraordinary events

    International Nuclear Information System (INIS)

    Woelfel, E.

    1977-01-01

    Nuclear power plant buildings must be functional to such an extend that even after the occurence of extraordinary events (earthquake, airoplane crash, gas cloud explosion), the reactor can be safety shut off, in order to avoid danger from the nuclear power plant. Evidence for this can only be given by calculations which shall meet the following requirements: The calculation results shall be safe and reliable. The calculation effort shall match the realizable accuracy. The calculation shall lead to an economical determination. An example of ascertainment of nuclear power plants in regard to earthquakes, shows the difficulties standing against a fulfillment of these requirements. (orig.) [de

  5. Nuclear and Radiological Event Scale Turns 20. INES Helps Authorities Rate Events and Communicate Their Significance

    International Nuclear Information System (INIS)

    Verlini, Giovanni

    2011-01-01

    Originally developed in the 1990s jointly by IAEA and Nuclear Energy Agency of the Organization for Economic Co-operation and Development (OECD/NEA) and Member States experts, INES was last revised in 2008 to become a more versatile and informative tool. INES is now designed to address events associated with the transport, storage and use of radioactive material and radiation sources, whether they occur at a nuclear installation or not.

  6. Future Contingents

    DEFF Research Database (Denmark)

    Øhrstrøm, Peter; Hasle., Per F. V.

    2015-01-01

    contingent statements. The problem of future contingents is interwoven with a number of issues in theology, philosophy, logic, semantics of natural language, computer science, and applied mathematics. The theological issue of how to reconcile the assumption of God's foreknowledge with the freedom and moral...... accountability of human beings has been a main impetus to the discussion and a major inspiration to the development of various logical models of time and future contingents. This theological issue is connected with the general philosophical question of determinism versus indeterminism. Within logic, the relation...... about the future. Finally, it should be mentioned that temporal logic has found a remarkable application in computer science and applied mathematics. In the late 1970s the first computer scientists realised the relevance of temporal logic for the purposes of computer science (see Hasle and Øhrstrøm 2004)....

  7. Future Contingents

    DEFF Research Database (Denmark)

    Øhrstrøm, Peter; Hasle., Per F. V.

    2011-01-01

    contingent statements. The problem of future contingents is interwoven with a number of issues in theology, philosophy, logic, semantics of natural language, computer science, and applied mathematics. The theological issue of how to reconcile the assumption of God's foreknowledge with the freedom and moral...... accountability of human beings has been a main impetus to the discussion and a major inspiration to the development of various logical models of time and future contingents. This theological issue is connected with the general philosophical question of determinism versus indeterminism. Within logic, the relation...... about the future. Finally, it should be mentioned that temporal logic has found a remarkable application in computer science and applied mathematics. In the late 1970s the first computer scientists realised the relevance of temporal logic for the purposes of computer science (see Hasle and Øhrstrøm 2004)....

  8. Protection of nuclear power plants against external events

    International Nuclear Information System (INIS)

    Kinet, P.; Roch, R.

    1978-01-01

    The paper describes the methodology of the safety design of nuclear power plants against external events with particular emphasis of the Belgian Plants. The site analysis and potential hazards evaluation are explained. The different designs incorporating various combinations of reinforced structures and dedicated systems are analysed. The particular lay-out and systems of the Belgian Plants are explained. (author)

  9. Protection of nuclear power plants against external events

    International Nuclear Information System (INIS)

    Suetterlin, L.

    1978-01-01

    The different aspects for the selection of external events to be accounted for in designing nuclear power plants and in defining load assumptions are illustrated: 1) In case of earthquake the severest possible events according to the state of science and technology are assumed. 2) For events where it is not or only to a certain extent possible to apply this method, e.g. in the load case airplane crash, load assumptions are defined in a combined probabilitic-deterministic way. By the example of plant protection, it is shown that by integrating all measures for protecting against interference of third parties (sabotage) or other external events, optimum protection concepts may be achieved. In all considerations on interference of third parties or other external events, one has to take into account that absolute protection is not possible. Nevertheless, it may be confirmed that nuclear power plants not only have a much higher level of protection than other, non-nuclear plants with equal or even higher potential hazard, but also that they meet the requirement not to increase significantly the current risk of society. (orig./HP) [de

  10. Recurring Events in the Finnish Nuclear Power Plants

    International Nuclear Information System (INIS)

    Suksi, Seija; Olander, Ronnie; Tiippana, Petteri

    2003-01-01

    An analysis and evaluation of event investigation methods applied by the Radiation and Nuclear Safety Authority (STUK), and the two Finnish nuclear power plant operators Teollisuuden Voima Oy (TVO) and Fortum Power and Heat Oy (Fortum) was carried out by the Technical Research Centre (VIT) on an assignment from STUK. The study aimed at providing a broad overview of the whole organisational framework to support event investigation practices at the regulatory body and at the utilities. The study was part of the IAEA Co-ordinated Research Programme (CRP) on 'Investigation of Methodologies for Incident Analysis'. The main objective of the research was to evaluate the adequacy and reliability of event investigation analysis methods and practices in the Finnish nuclear power industry and based on the results to further develop them. In general, the direct causes of identified events could be detected and eliminated, but more emphasis should be given to the prevention of recurrence of events and identification of common causes and latent failures. The study showed that the evaluated organisations had rather comprehensive incident analysis arrangements. The study also showed that more focus and prioritisation are needed. Deficiencies were identified mostly in the areas of recording, assessment and classification of new events, use of existing operating experience data, utilisation of information technology tools, and allocation of work and resources. Also the indicators or measures for the effectiveness of event investigation and operating experience feedback were missing. All organisations should maintain adequate resources in this area. The researchers suggested a more effective operating experience feedback loop. Especially more attention should be paid to root cause analysis of significant events, tasks and activities where the initial errors have occurred, and weaknesses of defensive barriers. It was also recommended that implementing periodic operational experience

  11. Analysis of water hammer events in nuclear power plants

    International Nuclear Information System (INIS)

    Sato, Masahiro; Yanagi, Chihiro

    1999-01-01

    A water hammer issue in nuclear power plants was one of unresolved safety issues listed by the United States Nuclear Regulatory Commission and was regarded as resolved. But later on, the water hammer events are still experienced intermittently, while the number of the events is decreasing. We collected water hammer events of PWRs in Japan and the United States and relevant documents, analyzed them, and studied corrective actions taken by Japanese plants. As a result, it is confirmed that preventive measured in design, operation etc. have been already taken and that mitigation mechanisms against water hammer have also been considered. However, it is clarified that attention should be continuously paid to operation of valves and/or pumps, as the prevention of water hammer still relies on operation. (author)

  12. Indemnification of Damage in the Event of a Nuclear Accident

    International Nuclear Information System (INIS)

    2006-01-01

    The Second International Workshop on the Indemnification of Nuclear Damage was held in Bratislava, Slovak Republic, from 18 to 20 May 2005. The workshop was co-organised by the OECD Nuclear Energy Agency and the Nuclear Regulatory Authority of the Slovak Republic. It attracted wide participation from national nuclear authorities, regulators, operators of nuclear installations, nuclear insurers and international organisations. The purpose of the workshop was to assess the third party liability and compensation mechanisms that would be implemented by participating countries in the event of a nuclear accident taking place within or near their borders. To accommodate this objective, two fictitious accident scenarios were developed: one involving a fire in a nuclear installation located in the Slovak Republic and resulting in the release of significant amounts of radioactive materials off-site, and the other a fire on board a ship transporting enriched uranium hexafluoride along the Danube River. The first scenario was designed to involve the greatest possible number of countries, with the second being restricted to countries with a geographical proximity to the Danube. These proceedings contain the papers presented at the workshop, as well as reports on the discussion sessions held. (author)

  13. Communicating about nuclear events: Some suggestions to improve INES

    International Nuclear Information System (INIS)

    Kermisch, Céline; Labeau, Pierre-Etienne

    2013-01-01

    This paper provides a critical analysis of the International Nuclear and Radiological Event Scale (INES) and its use, both from an epistemic and an ethical perspective. As very few papers have been dedicated to this subject, our critical analysis is mainly based on the INES 2009 User's Manual and on technical information issued by different nuclear agencies. Our critical analysis leads to suggest several elements, which could contribute to the improvement of the INES scale and thereby to a better communication about nuclear events. First, we show that multiple criteria are used to assign an INES rating, which could lead to an insufficient differentiation between events. In order to avoid this issue, we suggest to clarify the criteria that are used to assess the level of the event. Then, we show that level 7 of the INES scale is ill-defined as it does not allow to properly take differences in severity between disasters into account. In this regard, we recommend to use an open scale instead. Moreover, we highlight the fact that INES is able to take into account neither events with long-term evolution nor events involving multiple initiators. In this respect, we suggest providing additional guidelines and reflecting about the data on which to rely, in order to assess an INES level. Furthermore, we reflect on who should be rating a nuclear event and we recommend that, for severe events, an independent and plural agency should be in charge. Finally, we show why INES appears to be insufficient for a global communication, and we suggest to complement the INES rating with additional information in parallel. -- Highlights: •We provide a critical analysis of the INES scale and suggestions to improve it. •The rating criteria should be clarified to allow differentiation between events. •An open scale should be used to differentiate between level-7 accidents. •Additional guidelines should be provided for complex and evolving events. •We provide suggestions to satisfy

  14. FIREDATA, Nuclear Power Plant Fire Event Data Base

    International Nuclear Information System (INIS)

    Wheelis, W.T.

    2001-01-01

    1 - Description of program or function: FIREDATA contains raw fire event data from 1965 through June 1985. These data were obtained from a number of reference sources including the American Nuclear Insurers, Licensee Event Reports, Nuclear Power Experience, Electric Power Research Institute Fire Loss Data and then collated into one database developed in the personal computer database management system, dBASE III. FIREDATA is menu-driven and asks interactive questions of the user that allow searching of the database for various aspects of a fire such as: location, mode of plant operation at the time of the fire, means of detection and suppression, dollar loss, etc. Other features include the capability of searching for single or multiple criteria (using Boolean 'and' or 'or' logical operations), user-defined keyword searches of fire event descriptions, summary displays of fire event data by plant name of calendar date, and options for calculating the years of operating experience for all commercial nuclear power plants from any user-specified date and the ability to display general plant information. 2 - Method of solution: The six database files used to store nuclear power plant fire event information, FIRE, DESC, SUM, OPEXPER, OPEXBWR, and EXPERPWR, are accessed by software to display information meeting user-specified criteria or to perform numerical calculations (e.g., to determine the operating experience of a nuclear plant). FIRE contains specific searchable data relating to each of 354 fire events. A keyword concept is used to search each of the 31 separate entries or fields. DESC contains written descriptions of each of the fire events. SUM holds basic plant information for all plants proposed, under construction, in operation, or decommissioned. This includes the initial criticality and commercial operation dates, the physical location of the plant, and its operating capacity. OPEXPER contains date information and data on how various plant locations are

  15. 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)

  16. Trend analysis of fire events at nuclear power plants

    International Nuclear Information System (INIS)

    Shimada, Hiroki

    2007-01-01

    We performed trend analyses to compare fire events occurring overseas (1995-2005) and in Japan (1966-2006). We decided to do this after extracting data on incidents (storms, heavy rain, tsunamis, fires, etc.) occurring at overseas nuclear power plants from the Events Occurred at Overseas Nuclear Power Plants recorded in the Nuclear Information Database at the Institute of Nuclear Safety System (INSS) and finding that fires were the most common of the incidents. Analyses compared the number of fires occurring domestically and overseas and analyzed their causes and the effect of the fires on the power plants. As a result, we found that electrical fires caused by such things as current overheating and electric arcing, account for over one half of the domestic and overseas incidents of fire, which indicates that maintenance management of electric facilities is the most important aspect of fire prevention. Also, roughly the same number of operational fires occurred at domestic and overseas plants, judging from the figures for annual occurrences per unit. However, the overall number of fires per unit at domestic facilities is one fourth that of overseas facilities. We surmise that, while management of operations that utilizes fire is comparable for overseas and domestic plants, this disparity results from differences in the way maintenance is carried out at facilities. (author)

  17. Hydrogeologic effects of natural disruptive events on nuclear waste repositories

    International Nuclear Information System (INIS)

    Davis, S.N.

    1980-06-01

    Some possible hydrogeologic effects of disruptive events that may affect repositories for nuclear waste are described. A very large number of combinations of natural events can be imagined, but only those events which are judged to be most probable are covered. Waste-induced effects are not considered. The disruptive events discussed above are placed into four geologic settings. Although the geology is not specific to given repository sites that have been considered by other agencies, the geology has been generalized from actual field data and is, therefore, considered to be physically reasonable. The geologic settings considered are: (1) interior salt domes of the Gulf Coast, (2) bedded salt of southeastern New Mexico, (3) argillaceous rocks of southern Nevanda, and (4) granitic stocks of the Basin and Range Province. Log-normal distributions of permeabilities of rock units are given for each region. Chapters are devoted to: poresity and permeability of natural materials, regional flow patterns, disruptive events (faulting, dissolution of rock forming minerals, fracturing from various causes, rapid changes of hydraulic regimen); possible hydrologic effects of disruptive events; and hydraulic fracturing

  18. The initiating events in the Loviisa nuclear power plant history

    International Nuclear Information System (INIS)

    Sjoblom, K.

    1987-01-01

    During the 16 reactor years of Loviisa nuclear power plant operation no serious incident has endangered the high level of safety. The initiating events of plant incidents have been analyzed in order to get a view of plant operational safety experience. The initiating events have been placed in categories similar to those that EPRI uses. However, because of the very small number of scrams the study was extended to also cover transients with a relatively low safety importance in order to get more comprehensive statistics. Human errors, which contributed to 15% of the transients, were a special subject in this study. The conditions under which human failures occurred, and the nature and root causes of the human failures that caused the initiating events were analyzed. For future analyses it was noticed that it would be beneficial to analyze incidents immediately, to consult with the persons directly involved and to develop an international standard format for incident analyses

  19. Advanced nuclear plant design options to cope with external events

    International Nuclear Information System (INIS)

    2006-02-01

    With the stagnation period of nuclear power apparently coming to an end, there is a renewed interest in many Member States in the development and application of nuclear power plants (NPPs) with advanced reactors. Decisions on the construction of several NPPs with evolutionary light water reactors have been made (e.g. EPR Finland for Finland and France) and more are under consideration. There is a noticeable progress in the development and demonstration of innovative high temperature gas cooled reactors, for example, in China, South Africa and Japan. The Generation IV International Forum has defined the International Near Term Deployment programme and, for a more distant perspective, six innovative nuclear energy systems have been selected and certain R and D started by several participating countries. National efforts on design and technology development for NPPs with advanced reactors, both evolutionary and innovative, are ongoing in many Member States. Advanced NPPs have an opportunity to be built at many sites around the world, with very broad siting conditions. There are special concerns that safety of these advanced reactors may be challenged by external events following new scenarios and failure modes, different from those well known for the currently operated reactors. Therefore, the engineering community identified the need to assess the proposed design configurations in relation to external scenarios at the earliest stages of the design development. It appears that an early design optimization in relation to external events is a necessary requirement to achieve safe and economical advanced nuclear power plants. Reflecting on these developments, the IAEA has planned the preparation of a report to define design options for protection from external event impacts in NPPs with evolutionary and innovative reactors. The objective of this publication is to present the state-of-the-art in design approaches for the protection of NPPs with evolutionary and innovative

  20. Systems for reporting unusual events in nuclear power plants

    International Nuclear Information System (INIS)

    1989-01-01

    Many Member States with nuclear power programmes have established, and are operating, systems for collecting, assessing and disseminating information on safety related events in nuclear power plants. The Agency has recognized the importance of such systems and of achieving compatibility between them. It also recognizes the advantage to be derived from international efforts to exchange operational experience on a worldwide basis. In response to requests put forward during the Special Session of the IAEA General Conference held in September 1986, and to the recommendations made by the International Nuclear Safety Advisory Group (INSAG) to strengthen international co-operation in nuclear safety and the exchange of information on operating experience, the IAEA has been following a two-step approach. Firstly, it continues to assist Member States to establish, improve or harmonize their national systems for collecting, assessing and disseminating safety related operational experience, and secondly, it continues to reinforce the IAEA system for reporting unusual events with safety significance (IAEA Incident Reporting System - IAEA-IRS). Although the prime objective of both activities is to assist regulatory bodies and operating organizations to improve operational safety, operating organizations may also benefit if a similar approach is used to improve equipment reliability and plant availability. The present Guide contains a recommended scheme based on national and international practice applicable to the management of safety related operational experience in nuclear power plants. The user will have to adapt this guidance for specific national conditions and practices. It is important to realize however that for an effective exchange of information through the IAEA-IRS it is a prerequisite to follow the procedures given in the relevant part of this Guide

  1. The fate and importance of radionuclides produced in nuclear events

    Energy Technology Data Exchange (ETDEWEB)

    Shore, B; Anspaugh, L; Chertok, R; Gofman, J; Harrison, F; Heft, R; Koranda, J; Ng, Y; Phelps, P; Potter, G; Tamplin, A [Lawrence Radiation Laboratory, University of California, Livermore, CA (United States)

    1969-07-01

    Some of the major program at the Bio-Medical Division concerned with the fate and importance of the fission products, the radionuclides induced in the device materials, the radionuclides induced in the environment surrounding the device, and the tritium produced in Plowshare cratering events will be discussed. These programs include (1) critical unknowns in predicting organ and body burdens from radionuclides produced in cratering events; (2) the analysis with a high-resolution solid state gamma ray spectrometer of radionuclides in complex biological and environmental samples; (3) the characterization of radioactive particles from cratering detonation; (4) the biological availability to beagles, pigs and goats of radionuclides in Plowshare debris; (5) the biological availability to aquatic animals of radionuclides in Plowshare and other nuclear debris and the biological turnover of critical nuclides in specific aquatic animals; (6) the biological availability of Plowshare and other nuclear debris radionuclides to dairy cows and the transplacental transport of debris radionuclides in the dairy cow; (7) the persistence and behavior of radionuclides, particularly tritium, at sites of Plowshare and other nuclear detonations; and (8) somatic effects of Low Dose Radiation: Chromosome studies. (author)

  2. The fate and importance of radionuclides produced in nuclear events

    International Nuclear Information System (INIS)

    Shore, B.; Anspaugh, L.; Chertok, R.; Gofman, J.; Harrison, F.; Heft, R.; Koranda, J.; Ng, Y.; Phelps, P.; Potter, G.; Tamplin, A.

    1969-01-01

    Some of the major program at the Bio-Medical Division concerned with the fate and importance of the fission products, the radionuclides induced in the device materials, the radionuclides induced in the environment surrounding the device, and the tritium produced in Plowshare cratering events will be discussed. These programs include (1) critical unknowns in predicting organ and body burdens from radionuclides produced in cratering events; (2) the analysis with a high-resolution solid state gamma ray spectrometer of radionuclides in complex biological and environmental samples; (3) the characterization of radioactive particles from cratering detonation; (4) the biological availability to beagles, pigs and goats of radionuclides in Plowshare debris; (5) the biological availability to aquatic animals of radionuclides in Plowshare and other nuclear debris and the biological turnover of critical nuclides in specific aquatic animals; (6) the biological availability of Plowshare and other nuclear debris radionuclides to dairy cows and the transplacental transport of debris radionuclides in the dairy cow; (7) the persistence and behavior of radionuclides, particularly tritium, at sites of Plowshare and other nuclear detonations; and (8) somatic effects of Low Dose Radiation: Chromosome studies. (author)

  3. Root cause analysis for fire events at nuclear power plants

    International Nuclear Information System (INIS)

    1999-09-01

    Fire hazard has been identified as a major contributor to a plant' operational safety risk. The International nuclear power community (regulators, operators, designers) has been studying and developing tools for defending against this hazed. Considerable advances have been achieved during past two decades in design and regulatory requirements for fire safety, fire protection technology and related analytical techniques. The IAEA endeavours to provide assistance to Member States in improving fire safety in nuclear power plants. A task was launched by IAEA in 1993 with the purpose to develop guidelines and good practices, to promote advanced fire safety assessment techniques, to exchange state of the art information, and to provide engineering safety advisory services and training in the implementation of internationally accepted practices. This TECDOC addresses a systematic assessment of fire events using the root cause analysis methodology, which is recognized as an important element of fire safety assessment

  4. Contingency proportion systematically influences contingency learning.

    Science.gov (United States)

    Forrin, Noah D; MacLeod, Colin M

    2018-01-01

    In the color-word contingency learning paradigm, each word appears more often in one color (high contingency) than in the other colors (low contingency). Shortly after beginning the task, color identification responses become faster on the high-contingency trials than on the low-contingency trials-the contingency learning effect. Across five groups, we varied the high-contingency proportion in 10% steps, from 80% to 40%. The size of the contingency learning effect was positively related to high-contingency proportion, with the effect disappearing when high contingency was reduced to 40%. At the two highest contingency proportions, the magnitude of the effect increased over trials, the pattern suggesting that there was an increasing cost for the low-contingency trials rather than an increasing benefit for the high-contingency trials. Overall, the results fit a modified version of Schmidt's (2013, Acta Psychologica, 142, 119-126) parallel episodic processing account in which prior trial instances are routinely retrieved from memory and influence current trial performance.

  5. Trend analysis of explosion events at overseas nuclear power plants

    International Nuclear Information System (INIS)

    Shimada, Hiroki

    2008-01-01

    We surveyed failures caused by disasters (e.g., severe storms, heavy rainfall, earthquakes, explosions and fires) which occurred during the 13 years from 1995 to 2007 at overseas nuclear power plants (NPPs) from the nuclear information database of the Institute of Nuclear Safety System. Incorporated (INSS). The results revealed that explosions were the second most frequent type of failure after fires. We conducted a trend analysis on such explosion events. The analysis by equipment, cause, and effect on the plant showed that the explosions occurred mainly at electrical facilities, and thus it is essential to manage the maintenance of electrical facilities for preventing explosions. In addition, it was shown that explosions at transformers and batteries, which have never occurred at Japan's NPPs, accounted for as much as 55% of all explosions. The fact infers that this difference is attributable to the difference in maintenance methods of transformers (condition based maintenance adopted by NPPs) and workforce organization of batteries (inspections performed by utilities' own maintenance workers at NPPs). (author)

  6. Three Dimensional Simulation of the Baneberry Nuclear Event

    Science.gov (United States)

    Lomov, Ilya N.; Antoun, Tarabay H.; Wagoner, Jeff; Rambo, John T.

    2004-07-01

    Baneberry, a 10-kiloton nuclear event, was detonated at a depth of 278 m at the Nevada Test Site on December 18, 1970. Shortly after detonation, radioactive gases emanating from the cavity were released into the atmosphere through a shock-induced fissure near surface ground zero. Extensive geophysical investigations, coupled with a series of 1D and 2D computational studies were used to reconstruct the sequence of events that led to the catastrophic failure. However, the geological profile of the Baneberry site is complex and inherently three-dimensional, which meant that some geological features had to be simplified or ignored in the 2D simulations. This left open the possibility that features unaccounted for in the 2D simulations could have had an important influence on the eventual containment failure of the Baneberry event. This paper presents results from a high-fidelity 3D Baneberry simulation based on the most accurate geologic and geophysical data available. The results are compared with available data, and contrasted against the results of the previous 2D computational studies.

  7. Achieving world's highest level of nuclear safety learning from overseas nuclear trouble events

    International Nuclear Information System (INIS)

    Okumoto, Masaru

    2014-01-01

    Nuclear Information Research Project of Institute of Nuclear Safety System, Incorporated (INSS) had acquired trouble information of nuclear power plants (NPPs) up to annual several thousand events issued by overseas regulatory agencies for more than 20 years since INSS established and analyzed it in details respectively after the screening. Lessons extracted from the analysis were offered as suggestions to electric utilities having PWRs in Japan. Such activities would surely contribute to maintain and improve nuclear safety with no objection. However, they could not prevent the occurrence of accident of Fukushima Daiichi NPPs. Thus the project had reviewed usefulness of past activities and how improved could be by listening sincerely to outside opinions. This report introduced outlines of recent activities. Competent suggestions to electric utilities might be made with improved reflection of lessons to needed rules, deepened information sharing within the project and raised awareness of the problem. (T. Tanaka)

  8. Extreme meteorological events and nuclear facilities safety; Fenomenos meteorologicos extremos e a seguranca das instalacoes nucleares

    Energy Technology Data Exchange (ETDEWEB)

    Almeida, Patricia Moco Princisval

    2006-07-01

    An External Event is an event that originates outside the site and whose effects on the Nuclear Power Plants (NPP) should be considered. Such events could be of natural or human induced origin and should be identified and selected for design purposes during the site evaluation process. This work shows that the subtropics and mid latitudes of South America east of the Andes Mountain Range have been recognized as prone to severe convective weather. In Brazil, the events of tornadoes are becoming frequent; however there is no institutionalized procedure for a systematic documentation of severe weather. The information is done only for some scientists and by the newspapers. Like strong wind can affect the structural integrity of buildings or the pressure differential can affect the ventilation system, our concern is the safety of NPP and for this purpose the recommendations of International Atomic Energy Agency, Nuclear Regulatory Commission and Comissao Nacional de Energia Nuclear are showed and also a data base of tornadoes in Brazil is done. (author)

  9. The Principal of International Nuclear Event Scale Determination and Its Implementation

    International Nuclear Information System (INIS)

    Piping Supriatna

    2006-01-01

    International Nuclear Event Scale (INES) is a scale system for determination nuclear event level on an international scale. Comprehension of INES system commonly as a way to motivate communication between nuclear management and the public, in accordance with disturbance to public safety level as the impact of nuclear installation accident. By using INES as the scaling system, the nuclear event is easy to be understood by nuclear group, journalist or by the public directly. In this report has been analyzed the procedure of nuclear event level determination refer to INES scaling system and its implementation in the field. In order to get same perception in determination of nuclear event level, it is necessary to improve full comprehension for INES and its implementation. (author)

  10. Hipse: an event generator for nuclear collisions at intermediate energies

    International Nuclear Information System (INIS)

    Lacroix, D.; Van Lauwe, A.; Durand, D.

    2003-11-01

    An event generator, HIPSE (Heavy-Ion Phase-Space Exploration), dedicated to the description of nuclear collisions in the intermediate energy range is presented. Based on the sudden approximation and on geometrical hypothesis, it can conveniently simulate heavy-ion interactions at all impact parameters and thus can constitute a valuable tool for the understanding of processes such as neck emission or multifragmentation in peripheral or/and central collisions. After a detailed description of the ingredients of the model, first comparisons with experimental data collected by the INDRA collaboration are shown. Special emphasis is put on the kinematical characteristics of fragments and light particles observed at all impact parameters for Xe+Sn reactions at 25 and 50 MeV/u and Ni + Ni at 82 MeV/u. (authors)

  11. Automated track recognition and event reconstruction in nuclear emulsion

    International Nuclear Information System (INIS)

    Deines-Jones, P.; Aranas, A.; Cherry, M.L.; Dugas, J.; Kudzia, D.; Nilsen, B.S.; Sengupta, K.; Waddington, C.J.; Wefel, J.P.; Wilczynska, B.; Wilczynski, H.; Wosiek, B.

    1997-01-01

    The major advantages of nuclear emulsion for detecting charged particles are its submicron position resolution and sensitivity to minimum ionizing particles. These must be balanced, however, against the difficult manual microscope measurement by skilled observers required for the analysis. We have developed an automated system to acquire and analyze the microscope images from emulsion chambers. Each emulsion plate is analyzed independently, allowing coincidence techniques to be used in order to reject background and estimate error rates. The system has been used to analyze a sample of high-multiplicity Pb-Pb interactions (charged particle multiplicities ∝ 1100) produced by the 158 GeV/c per nucleon 208 Pb beam at CERN. Automatically measured events agree with our best manual measurements on 97% of all the tracks. We describe the image analysis and track reconstruction techniques, and discuss the measurement and reconstruction uncertainties. (orig.)

  12. Searching for Plausible N-k Contingencies Endangering Voltage Stability

    DEFF Research Database (Denmark)

    Weckesser, Johannes Tilman Gabriel; Van Cutsem, Thierry

    2017-01-01

    This paper presents a novel search algorithm using time-domain simulations to identify plausible N − k contingencies endangering voltage stability. Starting from an initial list of disturbances, progressively more severe contingencies are investigated. After simulation of a N − k contingency......, the simulation results are assessed. If the system response is unstable, a plausible harmful contingency sequence has been found. Otherwise, components affected by the contingencies are considered as candidate next event leading to N − (k + 1) contingencies. This implicitly takes into account hidden failures...

  13. Contingency strategy for insufficient full core off load capability in spent fuel pool for Chinshan nuclear power station

    International Nuclear Information System (INIS)

    Huang, Pinghue

    2012-01-01

    The spent fuel pool (SFP) at Taiwan Power Company's (TUC's) Chinshan plant lost the full core off load (FCO) capability in 2010, even with the second SFP repacking project to expand the capacity as reported in 12PBNC. The TEPC had originally planned to move some spent fuel assemblies from SFP to dry storage facility, however, the dry storage project had seriously fell behind. Thus, it is required to address insufficient FCO capability, and the following contingency measures have been employed: The first step was to explore whether there was a specific regulatory requirement for FCO capability, and none were identified. Also, the industrial experiences were explored. The refueling strategy is changed from FCO to in-core shuffling. A feasibility evaluation performed indicates the Technical Specifications require: alternate method of decay heat removal, and verification of shutdown margin for each in vessel fuel movement. Specific methods have been successfully established. A safety evaluation for operation without FCO capability was performed, and no safety concerns were identified. The risk for operation without FCO capability was assessed. The previous operational experiences were identified. Moreover, such works are not expected in subsequent cycles. The new fuel vault is used to store new fuel assemblies. The criticality analysis has been performed and some new approaches are proposed to enhance the storage flexibility as reported in 17PBNC. An inter-unit transfer cask has been designed to transfer spent fuel from the SFP of one unit to the other. The FCO capability can be effectively extended for three more years with this consideration. The TPC discussed the contingency strategy with the ROCAEC in May 2006, and the ROCAEC's concurrence was attained. With the proposed strategy, Chinshan units have been operating smoothly

  14. Contingency strategy for insufficient full core off load capability in spent fuel pool for Chinshan nuclear power station

    Energy Technology Data Exchange (ETDEWEB)

    Huang, Pinghue [Taiwan Power Company, Taipei (China)

    2012-03-15

    The spent fuel pool (SFP) at Taiwan Power Company's (TUC's) Chinshan plant lost the full core off load (FCO) capability in 2010, even with the second SFP repacking project to expand the capacity as reported in 12PBNC. The TEPC had originally planned to move some spent fuel assemblies from SFP to dry storage facility, however, the dry storage project had seriously fell behind. Thus, it is required to address insufficient FCO capability, and the following contingency measures have been employed: The first step was to explore whether there was a specific regulatory requirement for FCO capability, and none were identified. Also, the industrial experiences were explored. The refueling strategy is changed from FCO to in-core shuffling. A feasibility evaluation performed indicates the Technical Specifications require: alternate method of decay heat removal, and verification of shutdown margin for each in vessel fuel movement. Specific methods have been successfully established. A safety evaluation for operation without FCO capability was performed, and no safety concerns were identified. The risk for operation without FCO capability was assessed. The previous operational experiences were identified. Moreover, such works are not expected in subsequent cycles. The new fuel vault is used to store new fuel assemblies. The criticality analysis has been performed and some new approaches are proposed to enhance the storage flexibility as reported in 17PBNC. An inter-unit transfer cask has been designed to transfer spent fuel from the SFP of one unit to the other. The FCO capability can be effectively extended for three more years with this consideration. The TPC discussed the contingency strategy with the ROCAEC in May 2006, and the ROCAEC's concurrence was attained. With the proposed strategy, Chinshan units have been operating smoothly.

  15. Establishment of nuclear knowledge and information infrastructure; establishment of web-based database system for nuclear events

    Energy Technology Data Exchange (ETDEWEB)

    Park, W. J.; Kim, K. J. [Korea Atomic Energy Research Institute , Taejeon (Korea); Lee, S. H. [Korea Institute of Nuclear Safety, Taejeon (Korea)

    2001-05-01

    Nuclear events data reported by nuclear power plants are useful to prevent nuclear accidents at the power plant by examine the cause of initiating events and removal of weak points in the aspects of operational safety, and to improve nuclear safety in design and operation stages by backfitting operational experiences and practices 'Nuclear Event Evaluation Database : NEED' system distributed by CD-ROM media are upgraded to the NEED-Web (Web-based Nuclear Event Evaluation Database) version to manage event data using database system on network basis and the event data and the statistics are provided to the authorized users in the Nuclear Portal Site and publics through Internet Web services. The efforts to establish the NEED-Web system will improve the integrity of events data occurred in Korean nuclear power plant and the usability of data services, and enhance the confidence building and the transparency to the public in nuclear safety. 11 refs., 27 figs. (Author)

  16. GC Side Event: Future of Nuclear Energy: Engaging the Young Generation. Presentations

    International Nuclear Information System (INIS)

    2017-01-01

    This event presented the IAEA’s programmes for the education and training of a new generation of nuclear professionals. It also featured the annual European Master of Science in Nuclear Engineering (EMSNE) award ceremony

  17. Dynamic Contingency Analysis Tool

    Energy Technology Data Exchange (ETDEWEB)

    2016-01-14

    The Dynamic Contingency Analysis Tool (DCAT) is an open-platform and publicly available methodology to help develop applications that aim to improve the capabilities of power system planning engineers to assess the impact and likelihood of extreme contingencies and potential cascading events across their systems and interconnections. Outputs from the DCAT will help find mitigation solutions to reduce the risk of cascading outages in technically sound and effective ways. The current prototype DCAT implementation has been developed as a Python code that accesses the simulation functions of the Siemens PSS/E planning tool (PSS/E). It has the following features: It uses a hybrid dynamic and steady-state approach to simulating the cascading outage sequences that includes fast dynamic and slower steady-state events. It integrates dynamic models with protection scheme models for generation, transmission, and load. It models special protection systems (SPSs)/remedial action schemes (RASs) and automatic and manual corrective actions. Overall, the DCAT attempts to bridge multiple gaps in cascading-outage analysis in a single, unique prototype tool capable of automatically simulating and analyzing cascading sequences in real systems using multiprocessor computers.While the DCAT has been implemented using PSS/E in Phase I of the study, other commercial software packages with similar capabilities can be used within the DCAT framework.

  18. ACCIDENTS AND UNSCHEDULED EVENTS ASSOCIATED WITH NON-NUCLEAR ENERGY RESOURCES AND TECHNOLOGY

    Science.gov (United States)

    Accidents and unscheduled events associated with non-nuclear energy resources and technology are identified for each step in the energy cycle. Both natural and anthropogenic causes of accidents or unscheduled events are considered. Data concerning these accidents are summarized. ...

  19. A method for selection of spent nuclear fuel (SNF) transportation route considering socioeconomic cost based on contingent valuation method (CVM)

    International Nuclear Information System (INIS)

    Kim, Young Sik

    2008-02-01

    A transportation of SNF may cause an additional radiation exposure to human beings. It means that the radiological risk should be estimated and managed quantitatively for the public who live near the shipments route. Before the SNF transportation is performed, the route selection is concluded based on the radiological risk estimated with RADTRAN code in existing method generally. It means the existing method for route selection is based only on the radiological health risk but there are not only the impacts related to the radiological health risk but also the socioeconomic impacts related to the cost. In this study, a new method and its numerical formula for route selection on transporting SNF is proposed based on cost estimation because there are several costs in transporting SNF. The total cost consists of radiological health cost, transportation cost, and socioeconomic cost. Each cost is defined properly to the characteristics of SNF transportation and many coefficients and variables describing the meaning of each cost are obtained or estimated through many surveys. Especially to get the socioeconomic cost, contingent valuation method (CVM) is used with a questionnaire. The socioeconomic cost estimation is the most important part of the total cost originated from transporting SNF because it is a very dominant cost in the total cost. The route selection regarding SNF transportation can be supported with the proposed method reasonably and unnecessary or exhausting controversies about the shipments could be avoided

  20. Hanford Facility contingency plan

    International Nuclear Information System (INIS)

    Sutton, L.N.; Miskho, A.G.; Brunke, R.C.

    1993-10-01

    The Hanford Facility Contingency Plan, together with each TSD unit-specific contingency plan, meets the WAC 173-303 requirements for a contingency plan. This plan includes descriptions of responses to a nonradiological hazardous materials spill or release at Hanford Facility locations not covered by TSD unit-specific contingency plans or building emergency plans. This plan includes descriptions of responses for spills or releases as a result of transportation activities, movement of materials, packaging, and storage of hazardous materials

  1. 25 CFR 39.501 - What is an emergency or unforeseen contingency?

    Science.gov (United States)

    2010-04-01

    ... 25 Indians 1 2010-04-01 2010-04-01 false What is an emergency or unforeseen contingency? 39.501... EQUALIZATION PROGRAM Contingency Fund § 39.501 What is an emergency or unforeseen contingency? An emergency or unforeseen contingency is an event that meets all of the following criteria: (a) It could not be planned for...

  2. Experience feedback of operation events in Ling'ao phase Ⅱ nuclear power plant

    International Nuclear Information System (INIS)

    Xiao Zhi; Tao Shusheng; Sun Guochen; Zhang Zengqing

    2012-01-01

    As a new operating nuclear power plant, Ling'ao Phase Ⅱ occurred 20 pieces of operational events in one year of first cycle. By analyzing the events in this paper, the causes of the events are mainly concentrated in three aspects: interface between commissioning and operating, DCS system and the management of human factors. Finally, author gives some suggestions on experience feedback, as a reference to other similar nuclear power plants. (authors)

  3. Preliminary Analysis of the Common Cause Failure Events for Domestic Nuclear Power Plants

    International Nuclear Information System (INIS)

    Kang, Daeil; Han, Sanghoon

    2007-01-01

    It is known that the common cause failure (CCF) events have a great effect on the safety and probabilistic safety assessment (PSA) results of nuclear power plants (NPPs). However, the domestic studies have been mainly focused on the analysis method and modeling of CCF events. Thus, the analysis of the CCF events for domestic NPPs were performed to establish a domestic database for the CCF events and to deliver them to the operation office of the international common cause failure data exchange (ICDE) project. This paper presents the analysis results of the CCF events for domestic nuclear power plants

  4. Initiating events in the safety probabilistic analysis of nuclear power plants

    International Nuclear Information System (INIS)

    Stasiulevicius, R.

    1989-01-01

    The importance of the initiating event in the probabilistic safety analysis of nuclear power plants are discussed and the basic procedures necessary for preparing reports, quantification and grouping of the events are described. The examples of initiating events with its occurence medium frequency, included those calculated for OCONEE reactor and Angra-1 reactor are presented. (E.G.)

  5. Views on ASSET guidelines from event 'T5' of Daya Bay Nuclear Power Station

    International Nuclear Information System (INIS)

    Hao Xiaofeng

    1997-01-01

    The event assessment methodology adopted by ASSET (Assessment of Safety Significant Events Team) of IAEA, and event 'T5' (abnormal control rod drop time) occurred in Daya Bay Nuclear Power Station, including the causes and the corrective actions are briefly presented. The assessment of the event is performed by using the ASSET methodology, some advantages and limits of the methodology in practice are pointed out

  6. Initiating Event Rates at U.S. Nuclear Power Plants. 1988 - 2013

    International Nuclear Information System (INIS)

    Schroeder, John A.; Bower, Gordon R.

    2014-01-01

    Analyzing initiating event rates is important because it indicates performance among plants and also provides inputs to several U.S. Nuclear Regulatory Commission (NRC) risk-informed regulatory activities. This report presents an analysis of initiating event frequencies at U.S. commercial nuclear power plants since each plant's low-power license date. The evaluation is based on the operating experience from fiscal year 1988 through 2013 as reported in licensee event reports. Engineers with nuclear power plant experience staff reviewed each event report since the last update to this report for the presence of valid scrams or reactor trips at power. To be included in the study, an event had to meet all of the following criteria: includes an unplanned reactor trip (not a scheduled reactor trip on the daily operations schedule), sequence of events starts when reactor is critical and at or above the point of adding heat, occurs at a U.S. commercial nuclear power plant (excluding Fort St. Vrain and LaCrosse), and is reported by a licensee event report. This report displays occurrence rates (baseline frequencies) for the categories of initiating events that contribute to the NRC's Industry Trends Program. Sixteen initiating event groupings are trended and displayed. Initiators are plotted separately for initiating events with different occurrence rates for boiling water reactors and pressurized water reactors. p-values are given for the possible presence of a trend over the most recent 10 years.

  7. Study of event sequence database for a nuclear power domain

    International Nuclear Information System (INIS)

    Kusumi, Yoshiaki

    1998-01-01

    A retrieval engine developed to extract event sequences from an accident information database using a time series retrieval formula expressed with ordered retrieval terms is explored. This engine outputs not only a sequence which completely matches with a time series retrieval formula, but also sequence which approximately matches the formula (fuzzy retrieval). An event sequence database in which records consist of three ordered parameters, namely the causal event, the process and result. Then the database is used to assess the feasibility of this engine and favorable results were obtained. (author)

  8. Analysis on typical illegal events for nuclear safety class 1 valve

    International Nuclear Information System (INIS)

    Tian Dongqing; Gao Runsheng; Jiao Dianhui; Yang Lili; Chen Peng

    2014-01-01

    Illegal welding events of nuclear safety class l valve forging occurred to the manufacturer, while the valve was returned to be repaired. Illegal nondestructive test event of nuclear safety class valve occurred also to the manufacturer in the manufacturing process. The two events have resulted in quality incipient fault for the installed valves and the valves in the manufacturing process. It was reflected that operation of the factory quality assurance system isn't activated, and nuclear power engineering and operating company have insufficient supervision. The event-related parties should strengthen quality management and process control, get rid of the quality incipient fault, and experience feedback should be done well to guarantee quality of equipment in nuclear power plant. (authors)

  9. Analysis of external flooding events occurred in foreign nuclear power plant sites

    International Nuclear Information System (INIS)

    Li Dan; Cai Hankun; Xiao Zhi; An Hongzhen; Mao Huan

    2013-01-01

    This paper screens and studies 17 external flooding events occurred in foreign NPP sites, analysis the characteristic of external flooding events based on the source of the flooding, the impact on the building, systems and equipment, as well as the threat to nuclear safety. Furthermore, based on the experiences and lessons learned from Fukushima nuclear accident relating to external flooding and countermeasures carried out in the world, some suggestions are proposed in order to improve external flooding response capacity for Chinese NPPs. (authors)

  10. Suited Contingency Ops Food - 2

    Science.gov (United States)

    Glass, J. W.; Leong, M. L.; Douglas, G. L.

    2014-01-01

    The contingency scenario for an emergency cabin depressurization event may require crewmembers to subsist in a pressurized suit for up to 144 hours. This scenario requires the capability for safe nutrition delivery through a helmet feed port against a 4 psi pressure differential to enable crewmembers to maintain strength and cognition to perform critical tasks. Two nutritional delivery prototypes were developed and analyzed for compatibility with the helmet feed port interface and for operational effectiveness against the pressure differential. The bag-in-bag (BiB) prototype, designed to equalize the suit pressure with the beverage pouch and enable a crewmember to drink normally, delivered water successfully to three different subjects in suits pressurized to 4 psi. The Boa restrainer pouch, designed to provide mechanical leverage to overcome the pressure differential, did not operate sufficiently. Guidelines were developed and compiled for contingency beverages that provide macro-nutritional requirements, a minimum one-year shelf life, and compatibility with the delivery hardware. Evaluation results and food product parameters have the potential to be used to improve future prototype designs and develop complete nutritional beverages for contingency events. These feeding capabilities would have additional use on extended surface mission EVAs, where the current in-suit drinking device may be insufficient.

  11. Medical intervention in case of nuclear or radiation event

    International Nuclear Information System (INIS)

    Blanc, J.; Bourguignon, M.; Carli, P.; Carosella, E.; Challeton de Vathaire, C.; Court, L.; Ducousso, R.; Facon, A.; Fleutot, J.B.; Goldstein, P.; Gourmelon, P.; Herbelet, G.; Kolodie, H.; Lallemand, J.; Martin, J.C.; Menthonnex, P.; Masse, R.; Origny, S.; Pasnon, J.; Peton Klein, D.; Rougy, C.; Schoulz, D.; Romet, G.; Telion, C.; Vrousos, C.

    2002-01-01

    This guide aims to be a practical tool for intervenors in case of nuclear or radiation accident. It proposes many sheets to favor the reactivity and the implementing of adapted measures. It concerns the course of action to take in case of irradiation accident or contamination and the reception in medical structure or a hospital. (A.L.B.)

  12. Cause trending analysis for licensing operational events in Daya Bay Nuclear Power Station

    International Nuclear Information System (INIS)

    Wang Dewei

    2005-01-01

    The human causal factors for all human error licensing operational events on Daya Bay nuclear power station since 1993 to 2003 are categorized, the trend of these causal factors is analyzed. The emphasis is placed on analyzing the deficiencies on complying with and executing regulations and procedures. The results provide directional reference for nuclear power station to improve human performance. (author)

  13. Nuclear Security Systems and Measures for Major Public Events. Implementing Guide (French Edition)

    International Nuclear Information System (INIS)

    2017-01-01

    This publication provides an overview, based on practical experience and lessons learned, for establishing nuclear security systems and measures for major public events. It covers technical and administrative nuclear security measures for developing the necessary organizational structure, developing plans, strategies and concepts of operations, and making arrangements for implementing the developed plans, strategies and concepts.

  14. Notifiable events in German nuclear power plants in 1992

    International Nuclear Information System (INIS)

    Anon.

    1993-01-01

    In 1992, there were 223 notifiable nuclear power plant incidents in the Federal Republic of Germany. 221 incidents belong to the category N (normal notification, INES 0), 2 incidents belong to the category E (immediate notification, INES 2). The report comprehensively lists all the incidents. No releases of radioactive materials above the, lincenced levels occupied and there were no hazards to persons and to the environment. (HP) [de

  15. Estimation of initiating event distribution at nuclear power plants by Bayesian procedure

    International Nuclear Information System (INIS)

    Chen Guangming

    1995-01-01

    Initiating events at nuclear power plants such as human errors or components failures may lead to a nuclear accident. The study of the frequency of these events or the distribution of the failure rate is necessary in probabilistic risk assessment for nuclear power plants. This paper presents Bayesian modelling methods for the analysis of the distribution of the failure rate. The method can also be utilized in other related fields especially where the data is sparse. An application of the Bayesian modelling in the analysis of distribution of the time to recover Loss of Off-Site Power ( LOSP) is discussed in the paper

  16. Event-by-Event Simulations of Early Gluon Fields in High Energy Nuclear Collisions

    Science.gov (United States)

    Nickel, Matthew; Rose, Steven; Fries, Rainer

    2017-09-01

    Collisions of heavy ions are carried out at ultra relativistic speeds at the Relativistic Heavy Ion Collider and the Large Hadron Collider to create Quark Gluon Plasma. The earliest stages of such collisions are dominated by the dynamics of classical gluon fields. The McLerran-Venugopalan (MV) model of color glass condensate provides a model for this process. Previous research has provided an analytic solution for event averaged observables in the MV model. Using the High Performance Research Computing Center (HPRC) at Texas A&M, we have developed a C++ code to explicitly calculate the initial gluon fields and energy momentum tensor event by event using the analytic recursive solution. The code has been tested against previously known analytic results up to fourth order. We have also have been able to test the convergence of the recursive solution at high orders in time and studied the time evolution of color glass condensate.

  17. Event classification related to overflow of solvent containing uranium according to the INES scale (International Nuclear and Radiological Event Scale)

    International Nuclear Information System (INIS)

    Dourado, Eneida R.G.; Assis, Juliana T. de; Lage, Ricardo F.; Lopes, Karina B.

    2013-01-01

    This paper aims to frame the event overflow organic solvent rich in uranium, from a decanter of ore beneficiation plant, caused by the fall in the supply of electricity, according to the criteria established by the International Nuclear Event Scale and radiological (INES), facilitating the understanding of the occurrence and communication with the public regarding the radiation safety aspects involved. With the fall of electricity, routine procedures in situations of installation stop were performed, however, due to operational failure, the valve on the transfer line liquor was not closed. Thus, the mixer continued being fed with liquor, that led the consequent leakage of solvent loaded with uranium. It reached the drainage system, and the box of rainwater harvesting of the plant. However, immediately after the detection of the event, corrective actions were initiated and the overflow was contained. Regulatory agencies followed the removal of the solvent and on the results of the analysis of environmental monitoring, found that the event did not provide exposure to workers or any other impact. Therefore, comparing the characteristics of the event and the guidelines proposed by the INES scale, it is concluded that the classification of the event is below scale/level 0, confirming the absence of risk to the local population, workers and the environment

  18. Discrete-event simulation of nuclear-waste transport in geologic sites subject to disruptive events. Final report

    International Nuclear Information System (INIS)

    Aggarwal, S.; Ryland, S.; Peck, R.

    1980-01-01

    This report outlines a methodology to study the effects of disruptive events on nuclear waste material in stable geologic sites. The methodology is based upon developing a discrete events model that can be simulated on the computer. This methodology allows a natural development of simulation models that use computer resources in an efficient manner. Accurate modeling in this area depends in large part upon accurate modeling of ion transport behavior in the storage media. Unfortunately, developments in this area are not at a stage where there is any consensus on proper models for such transport. Consequently, our work is directed primarily towards showing how disruptive events can be properly incorporated in such a model, rather than as a predictive tool at this stage. When and if proper geologic parameters can be determined, then it would be possible to use this as a predictive model. Assumptions and their bases are discussed, and the mathematical and computer model are described

  19. Application of the double-contingency principle within BNFL

    International Nuclear Information System (INIS)

    Strafford, P.I.D.

    1995-01-01

    Historically, the double-contingency principle has been used for criticality assessment within British Nuclear Fuels plc (BNFL). This paper outlines what is understood by the double-contingency principle to illustrate how it is applied in criticality safety assessments and to highlight various problem areas that are encountered and, where possible, how they might be solved

  20. INES: The International Nuclear and Radiological Event Scale User's Manual. 2008 Edition (Spanish Edition)

    International Nuclear Information System (INIS)

    2010-11-01

    INES, the International Nuclear and Radiological Event Scale, was developed in 1990 by experts convened by the IAEA and the OECD Nuclear Energy Agency with the aim of communicating the safety significance of events. This edition of the INES User?s Manual is designed to facilitate the task of those who are required to rate the safety significance of events using the scale. It includes additional guidance and clarifications, and provides examples and comments on the continued use of INES. With this new edition, it is anticipated that INES will be widely used by Member States and become the worldwide scale for putting into proper perspective the safety significance of any event associated with the transport, storage and use of radioactive material and radiation sources, whether or not the event occurs at a facility.

  1. INES: The International Nuclear and Radiological Event Scale User's Manual. 2008 Edition (Chinese Edition)

    International Nuclear Information System (INIS)

    2012-01-01

    INES, the International Nuclear and Radiological Event Scale, was developed in 1990 by experts convened by the IAEA and the OECD Nuclear Energy Agency with the aim of communicating the safety significance of events. This edition of the INES User's Manual is designed to facilitate the task of those who are required to rate the safety significance of events using the scale. It includes additional guidance and clarifications, and provides examples and comments on the continued use of INES. With this new edition, it is anticipated that INES will be widely used by Member States and become the worldwide scale for putting into proper perspective the safety significance of any event associated with the transport, storage and use of radioactive material and radiation sources, whether or not the event occurs at a facility.

  2. GC Side Event: Africa's Energy Needs and the Potential Role of Nuclear Power. Presentations

    International Nuclear Information System (INIS)

    2015-01-01

    Energy is central to development, and energy availability, accessibility and affordability are central challenges for most African countries. Due to rapidly growing energy demand, the need for socioeconomic development, persistent concerns over climate change and environmental impacts and dependence on imported supplies of fossil fuels, African Member States are looking into possible options to secure sustainable energy supplies, including nuclear energy. The IAEA assists those countries in assessing the nuclear power option and building the necessary infrastructure for a safe, secure and sustainable nuclear power programme. This year, the IAEA is conducting Integrated Nuclear Infrastructure Review (INIR) missions to three African countries (Nigeria, Kenya and Morocco) considering introducing nuclear power. The side event presents recent updates from Africa on the potential role of nuclear power, including the IAEA Third Regional Conference on Energy and Nuclear Power in Africa, held in Mombasa, Kenya, in April 2015, an initiative to launch a new African network for enhancing nuclear power programme development, and others. The event reports on recent developments in several African Member States considering, embarking on, or expanding national nuclear power programmes.

  3. Investigation and analysis of hydrogen ignition and explosion events in foreign nuclear power plants

    Energy Technology Data Exchange (ETDEWEB)

    Okuda, Yasunori [Institute of Nuclear Safety System, Inc., Mihama, Fukui (Japan)

    2002-09-01

    Reports about hydrogen ignition and explosion events in foreign nuclear power plants from 1980 to 2001 were investigated, and 31 events were identified. Analysis showed that they were categorized in (1) outer leakage ignition events and (2) inner accumulation ignition events. The dominant event for PWR (pressurized water reactor) was outer leakage ignition in the main generator, and in BWR (boiling water reactor) it was inner accumulation ignition in the off-gas system. The outer leakage ignition was a result of work process failure with the ignition source, operator error, or main generator hydrogen leakage. The inner accumulation ignition events were caused by equipment failure or insufficient monitoring. With careful preventive measures, the factors leading to these events could be eliminated. (author)

  4. Electrical systems at the nuclear power plant of Laguna Verde after the event in Fukushima

    International Nuclear Information System (INIS)

    Lopez J, J. F.

    2016-09-01

    During the event at the nuclear power plant of Fukushima Daichii (Japan), the electrical systems were affected both Onsite and Offsite, which were lost for a long time with irreversible consequences. Therefore, the Mexican Regulatory Body known as the Comision Nacional de Seguridad Nuclear y Salvaguardias (CNSNS) has taken various actions to review the current capacity of the electrical systems at the nuclear power plant of Laguna Verde (NPP-LV) before an event beyond the design bases. The CNSNS made special inspections to the NPP-LV to verify the current capacity of the electrical systems of Ac and Dc; as a result of the inspections, requirements were generated that must be met to demonstrate that has the capacity to deal with events beyond the design bases. In addition, CNSNS has participated in the Ibero-American Forum to deal with resistance testing. Is important to note that prior to the event at the nuclear power plant of Fukushima, the NPP-LV had implemented 1) the project Extended Power Increase in both Units of the NPP-LV, and 2) the Generic Charter 2006-02, both issues are considered contributions in the robustness of electrical systems. But it is also important to mention that the US Nuclear Regulatory Commission will soon issue mitigation strategies for a Station Blackout event, which could involve new actions at nuclear power plants. Based on the aforementioned, the CNSNS concludes that all the actions being taken contribute to the strengthening of the NPP-LV electrical systems, in order to increase their reliability, safety and operation when these are required to deal with events beyond the design bases as the event occurred in Fukushima Daichii and avoid as far as possible, damage in the reactor cores of the NPP-LV. (Author)

  5. Prediction of accident sequence probabilities in a nuclear power plant due to earthquake events

    International Nuclear Information System (INIS)

    Hudson, J.M.; Collins, J.D.

    1980-01-01

    This paper presents a methodology to predict accident probabilities in nuclear power plants subject to earthquakes. The resulting computer program accesses response data to compute component failure probabilities using fragility functions. Using logical failure definitions for systems, and the calculated component failure probabilities, initiating event and safety system failure probabilities are synthesized. The incorporation of accident sequence expressions allows the calculation of terminal event probabilities. Accident sequences, with their occurrence probabilities, are finally coupled to a specific release category. A unique aspect of the methodology is an analytical procedure for calculating top event probabilities based on the correlated failure of primary events

  6. Consideration of external events in the design of nuclear facilities other than nuclear power plants, with emphasis on earthquakes

    International Nuclear Information System (INIS)

    2003-03-01

    The design of nuclear facilities other than nuclear power plants in relation to external events is not a well harmonized practice around the world. Traditionally, the design of these facilities has either been left to the provisions collected in national building codes and other industrial codes not specifically intended for nuclear facilities, or it has been the subject of complex analyses of the type usually performed for nuclear power plants. The IAEA has recently started a programme of development of safety standards for such facilities. The need to define the appropriate safety requirements for nuclear installations prompted a generic review of siting and design approaches for these facilities in relation to external events. Therefore the assessment methods for siting and design were reviewed by the engineering community to provide the overall design of such facilities with the necessary reliability level. This report aims to provide guidelines for the assessment of the safety of nuclear facilities other than nuclear power plants in relation to external events through the application of simplified methods and procedures for their siting and design. The approach adopted is both simplified and conservative compared with that used for power reactors. It seeks to provide a rational balance for a suitable combination of sustainable effort in site investigations and refinement in design procedures, compatible with the assigned safety objectives. This publication is related to IAEA-TECDOC-348 'Earthquake Resistant Design of Nuclear Facilities with Limited Radioactive Inventory' (1985) which focused on the seismic design of nuclear facilities with limited radioactive inventory. After some 17 years, parts of IAEA-TECDOC-348 needed modification, as new operational data have become available from many facilities. In addition, sophisticated design methodologies are now more easily obtainable, and experts felt that the trade-off between sustainable investment in the

  7. The cause multiplicity and the multiple cause style of adverse events in Japanese nuclear power plants

    International Nuclear Information System (INIS)

    Miyazaki, Takamasa

    2008-01-01

    An adverse event in a nuclear power plant occurs due to either one cause or multiple causes. To consider ways of preventing adverse events, it is useful to clarify whether events are caused by single or multiple causes. In this study, the multiple causes is expressed using the cause multiplicity and the multiple cause style. Classified causes of adverse events in Japanese nuclear power plants were analyzed, with the following results: the cause multiplicity of serious adverse events is higher than that of minor adverse events, and the multiple cause style can be expressed by combining two styles: series type and parallel type. Also, for a multiple cause event, a new method of displaying the event is presented as a cause-chain chart where the cause items are arranged in a sequential way and are connected considering the mutual relations among the causes. This new display method shows the whole flow of issues concerning the event more simply than the conventional display method of the chain of phenomena, and would be useful for considering the terminating point of the chain of causes. (author)

  8. Nuclear and energies. Synthesis of significant events from June 2013 to December 2013

    International Nuclear Information System (INIS)

    Lenail, Bernard; Ducroux, Guy; Lamorlette, Guy; Seyve, Claude; Simonnet, Jacques; Bordier, Jean-Claude; Justin, Francois; Darricau, Aime; Seyve, Claude; Raisonnier, Daniele; Lenail, Bernard; Deleigne, Francoise

    2013-12-01

    The first two articles concern the energy sector, generally speaking. Among them, the first one addresses the issue of energy transition (perspectives in France, situation in Germany where transition appears to be expensive and polluting with some perverse effects, a world shock wave created by shale gases, proposition by EDF to extend power station life duration from 40 to 50 years, EDF's commitment in nuclear revival in the UK and withdrawal from the USA, new strategy for GDF-Suez) and the second one current events in the renewable energy sector (in China, Germany, UK and Canada, French policy, wind energy bids in France). A second set of articles addresses the nuclear sector: recent evolutions of the uranium industry (mining activities and locations), the back end of the fuel cycle and the dismantling (activities of AREVA, public debate on Cigeo and building permit for ICEDA in France, activities and measures in Germany, in England, in the USA, and in Japan, study performed by the Nuclear Energy Agency on the economic aspect of the back end of the nuclear fuel cycle), the situation of nuclear reactors (perspectives in the world for 2050, perspectives, activities and important events in France, Belgium, Netherlands, United Kingdom, Finland, including the EPR, Turkey, Poland, Czech Republic, Belarus, Russia, China, South Korea, India, Pakistan, Japan, USA and Brazil), the deconstruction of nuclear power plants (legal framework in France, wastes as a major issue for dismantling, industrial challenges of dismantling). The last set of articles concern social and societal aspects of the nuclear sector: recent events in France (for AREVA regarding staff and investments, anti-nuclear activities and momentum), the Cigeo project of geological disposal of high-activity nuclear wastes, hostages in Niger, and diplomatic advances about the Iranian nuclear programme issue

  9. Radioactive Reversal? The Fukushima Accident as a Focusing Event for Comparative Policy Change on Nuclear Energy

    Science.gov (United States)

    Sanchez, Victoria Justine

    This dissertation project examines the 2011 Fukushima nuclear accident as a focusing event for policy change on nuclear energy. For example, following the accident, Germany (and much of Europe) experienced a reversal of policy on nuclear energy. Conversely, many others such as China, Russia, and France, did not exhibit such a retraction against nuclear power, albeit with public debate about the risks and consequences of accidents. Why has there been dramatic policy change in some cases but not others? The political and literal fallout of Fukushima has provoked a wave of policy change towards nuclear energy at the national level. Through qualitative and quantitative measures, we can view Fukushima as an impetus for comparing the dynamics of nuclear policy change. Quantitatively, this project employs logistic regression to explore variables such as regime type, energy security, trade supply and demand, climate change concerns, and public acceptance are related to policy outcomes and change on nuclear energy in the post-Fukushima context of 49 different countries. Qualitatively, country cases (Russia, Germany, and Canada) are assessed into three categories based on the outcome of policy decisions on nuclear energy following Fukushima for a richer analysis. Beyond the Fukushima example, we can hope to better understand how political focusing events can gain influence in an international context.

  10. Compilation of INES (International Nuclear Event Scale) information. Japanese translation (Vol.2)

    Energy Technology Data Exchange (ETDEWEB)

    Watanabe, Norio [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment

    2001-03-01

    The International Nuclear Event Scale (INES) is a means designed for providing prompt, clear and consistent information related to nuclear events, that occurred at nuclear power plants and at other nuclear facilities, and facilitating communication between the nuclear community, the media and the public on such events. The INES is jointly operated by the International Atomic Energy Agency (IAEA) and the Nuclear Energy Agency of the Organization for Economic Co-operation and Development (OECD/NEA). Nuclear events reported to the INES Information System from member countries of IAEA and/or OECD/NEA are rated by the 'Scale', a consistent safety significance indicator. The scale runs from level 0, for events with no safety significance, to level 7 for a major accident with widespread health and environmental effects. The INES was introduced in March 1990 for a trial and then formally adopted in March 1992. In Japan, the INES was formally introduced in August 1992. The Japan Atomic Energy Research Institute (JAERI) has been receiving the INES information through the Science and Technology Agency, promptly translating into Japanese and providing to the relevant sections inside and outside JAERI. As well, we published the report compiling the Japanese translation of individual INES reports until May 31, 1998. Since then, we have developed a world-wide-web database for the Japanese translation and made it available to the public through the internet. This report compiles the Japanese version of approximately 70 INES reports we received from June 1, 1998 to December 31, 2000. (author)

  11. Just and reasonable distribution of funds for limited damages in the event of nuclear disasters

    International Nuclear Information System (INIS)

    Schattke, H.

    1985-01-01

    A suggestion is made to make legal dispositions for the distribution of funds before a nuclear event. The concept incorporates the following material-legal elements: Proportionate reduction of damages compensation claims in case the funds for liability and coverage are insufficient; creation of reserve funds for late damage; legal preference of personal damage and only subsequent satisfaction of demand for compensation of nuclear industries. (orig.) [de

  12. World wide web for database of Japanese translation on international nuclear event scale reports

    International Nuclear Information System (INIS)

    Watanabe, Norio; Hirano, Masashi

    1999-01-01

    The International Nuclear Event Scale (INES) is a means designed for providing prompt, clear and consistent information related to nuclear events, that occurred at nuclear facilities, and facilitating communication between the nuclear community, the media and the public. The INES is jointly operated by the IAEA and the OECD-NEA. Nuclear events reported are rated by the Scale', a consistent safety significance indicator. The scale runs from level 0, for events with no safety significance, to level 7 for a major accident with widespread health and environmental effects. The Japan Atomic Energy Research Institute (JAERI) has been promptly translating the INES reports into Japanese and developing a world-wide-web database for the Japanese translation, aiming at more efficient utilization of the INES information inside Japan. The present paper briefly introduces the definitions of INES rating levels and the scope of the Scale, and describes the outlines of the database (the information stored in the database, its functions and how to use it). As well, technical use of the INES reports and the availability/ effectiveness of the database are discussed. (author)

  13. The nuclear and radiological terrorism events and the strategy to combat

    International Nuclear Information System (INIS)

    Wang Shanqiang

    2004-01-01

    The super-terrorism using large-scale antipersonnel weapons has become one real threat for the contemporary international society to face. The radioactive materials releasing from the nuclear and radiological terrorism events will cause the personnel dead and injured with mental state dismay, which break national official business, people life, society stability and economy development, and give mankind social result in endanger with large affect and have been concerned by the people all over the world. This paper analyzes the possible pattern and harmfulness of the nuclear and radiological terrorism events, at the same time puts forward the strategy to combat them according to their three categories and typical scenes. (author)

  14. Analysis of events occurred at overseas nuclear power plants in 2004

    International Nuclear Information System (INIS)

    Miyazaki, Takamasa; Nishioka, Hiromasa; Sato, Masahiro; Chiba, Gorou; Takagawa, Kenichi; Shimada, Hiroki

    2005-01-01

    The Institute of Nuclear Safety Systems (INSS) investigates the information related to events and incidents occurred at overseas nuclear power plants, and proposes recommendations for the improvement of the safety and reliability of domestic PWR plants by evaluating them. Succeeding to the 2003 report, this report shows the summary of the evaluation activity and of the tendency analysis based on about 2800 information obtained in 2004. The tendency analysis was undertaken on about 1700 analyzed events, from the view point of mechanics, electrics and operations, about the causes, troubled equipments and so on. (author)

  15. Trend analysis of nuclear reactor automatic trip events subjected to operator's human error at United States nuclear power plants

    International Nuclear Information System (INIS)

    Takagawa, Kenichi

    2009-01-01

    Trends in nuclear reactor automatic trip events due to human errors during plant operating mode have been analyzed by extracting 20 events which took place in the United States during the period of seven years from 2002 to 2008, cited in the LERs (Licensee Event Reports) submitted to the US Nuclear Regulatory Commission (NRC). It was shown that the yearly number of events was relatively large before 2005, and thereafter the number decreased. A period of stable operation, in which the yearly number was kept very small, continued for about three years, and then the yearly number turned to increase again. Before 2005, automatic trip events occurred more frequently during periodic inspections or start-up/shut-down operations. The recent trends, however, indicate that trip events became more frequent due to human errors during daily operations. Human errors were mostly caused by the self-conceit and carelessness of operators through the whole period. The before mentioned trends in the yearly number of events might be explained as follows. The decrease in the automatic trip events is attributed to sharing trouble information, leading as a consequence to improvement of the manual and training for the operations which have a higher potential risk of automatic trip. Then, while the period of stable operation continued, some operators came to pay less attention to preventing human errors and not interest in the training, leading to automatic trip events in reality due to miss-operation. From these analyses on trouble experiences in the US, we learnt the followings to prevent the occurrence similar troubles in Japan: Operators should be thoroughly skilled in basic actions to prevent human errors as persons concerned. And it should be further emphasized that they should elaborate by imaging actual plant operations even though the simulator training gives them successful experiences. (author)

  16. Trend analysis of breaker events at United States nuclear power plants

    International Nuclear Information System (INIS)

    Shimada, Hiroki

    2006-01-01

    From events in overseas nuclear power plants recorded in the nuclear information detabase of Institute of Nuclear Safety System, Inc. (INSS), the number of events of electrical systems during the four years from 2002 to 2005 was extracted and the trend was analyzed. The results showed that breaker events were the largest in number in all years, and almost all them occurred in the US. The breaker events that occurred in US nuclear power plants in 2005 were analyzed by classifying them by cause of failure and effect on the plant, and by comparing the number of occurrences with that in Japan. As a result, the main cause of many of the breaker events was improper maintenance due to poor arrangement of maintenance manuals and human error, as well as aging degradation, they can be estimated to have been caused by insufficient maintenance control and inspection. The number of breaker failures per plant per year in our country was lower than that in the US by an order of magnitude, and there were no failures that led to a plant trip or power reduction. These facts suggest that our country's maintenance contents of breaker are advantage. (author)

  17. Nuclear and energies - Synthesis of striking events from December 2012 to May 2013. Nr 61/June

    International Nuclear Information System (INIS)

    Lenail, Bernard; Ducroux, Guy; Lamorlette, Guy; Seyve, Claude; Greneche, Dominique; Gollion, Jacques; Seyve, Claude; Darricau, Aime; Raisonnier, Daniele; Lepine, Gerard; Vandevoir, Roger

    2013-06-01

    This issue first proposes a comment on energy transition: challenges to define and reach a desirable energy mix in 2025, eventual scenarios to meet climatic commitments (factor-4 reduction of greenhouse gas emissions by 2050, compliance with the 3 x 20 pc European objective in 2020). A set of articles then proposes overviews and comments on the evolution of the energy sector, on recent events in the field of renewable energies, on the struggle against greenhouse effect. The next part more specifically addresses the nuclear energy: highlights and facts in the field of nuclear fuel (from mining to fuel production) and in the field of the back end of the fuel cycle (by Areva, and in different countries), perspectives for the Thorium fuel cycle (motivations for the use of the Thorium cycle, benefits and drawbacks), highlights and events regarding nuclear reactors in France, Belgium, United Kingdom, Finland, Turkey, Czech Republic, Hungary, Poland, Spain, China, Japan, Vietnam, Bangladesh, USA, Brazil and Argentina. A last set of articles addresses the relationship between nuclear and society: a focus on the situation in Sahel after the French military intervention in Mali (the hostage issue), the impact of nuclear power on the environment (with reference to events in France, in Germany, in Switzerland and in the USA), and issues related to nuclear proliferation (notably with North Korea and Iran)

  18. The dependency and contingency of politics

    DEFF Research Database (Denmark)

    Triantafillou, Peter

    2016-01-01

    differences which make any analytical synthesis both a difficult and a questionable endeavour. In particular, whereas historical institutionalism seeks to explain the present in terms of its dependence on past events, genealogy seeks to provoke the present by demonstrating its historical contingency. In spite...

  19. Nuclear emergency preparedness and response in Japan. Risk management and communication regarding nuclear events

    International Nuclear Information System (INIS)

    Sato, Hajime

    2011-01-01

    Severe accidents at nuclear plants can result in long-standing and large-scale disasters encompassing wide areas. The public may have special concerns regarding these plants and radiation-related health risks. It has therefore been argued that risk communications efforts, along with rigid safety management of nuclear plants, are imperative to prevent such accidents, mitigate their impacts, and alleviate public concerns. This article introduces a set of laws, acts, codes, and guidelines concerning nuclear safety in Japan. In addition, the preparedness and mitigation plans and programs for dealing with nuclear accidents and possible disasters are also discussed. Furthermore, the ongoing accidents at the Fukushima nuclear power plants following the Great East Japan Earthquake in 2011, and the government response to them are presented. A set of points regarding the management and communications of power plant accidents are discussed. (author)

  20. Multivariate algorithms for initiating event detection and identification in nuclear power plants

    International Nuclear Information System (INIS)

    Wu, Shun-Chi; Chen, Kuang-You; Lin, Ting-Han; Chou, Hwai-Pwu

    2018-01-01

    Highlights: •Multivariate algorithms for NPP initiating event detection and identification. •Recordings from multiple sensors are simultaneously considered for detection. •Both spatial and temporal information is used for event identification. •Untrained event isolation avoids falsely relating an untrained event. •Efficacy of the algorithms is verified with data from the Maanshan NPP simulator. -- Abstract: To prevent escalation of an initiating event into a severe accident, promptly detecting its occurrence and precisely identifying its type are essential. In this study, several multivariate algorithms for initiating event detection and identification are proposed to help maintain safe operations of nuclear power plants (NPPs). By monitoring changes in the NPP sensing variables, an event is detected when the preset thresholds are exceeded. Unlike existing approaches, recordings from sensors of the same type are simultaneously considered for detection, and no subjective reasoning is involved in setting these thresholds. To facilitate efficient event identification, a spatiotemporal feature extractor is proposed. The extracted features consist of the temporal traits used by existing techniques and the spatial signature of an event. Through an F-score-based feature ranking, only those that are most discriminant in classifying the events under consideration will be retained for identification. Moreover, an untrained event isolation scheme is introduced to avoid relating an untrained event to those in the event dataset so that improper recovery actions can be prevented. Results from experiments containing data of 12 event classes and a total of 125 events generated using a Taiwan’s Maanshan NPP simulator are provided to illustrate the efficacy of the proposed algorithms.

  1. Analysis of adverse events occurred at overseas nuclear power plants in 2003

    International Nuclear Information System (INIS)

    Miyazaki, Takamasa; Sato, Masahiro; Takagawa, Kenichi; Fushimi, Yasuyuki; Shimada, Hiroki; Shimada, Yoshio

    2004-01-01

    The adverse events that have occurred in the overseas nuclear power plants can be studied to provide an indication of how to improve the safety and the reliability of nuclear power plants in Japan. The Institute of Nuclear Safety Systems (INSS) obtains information related to overseas adverse events and incidents, and by evaluating them proposes improvements to prevent similar occurrences in Japanese PWR plants. In 2003, INSS obtained approximately 2800 pieces of information and, by evaluating them, proposed nine recommendations to Japanese utilities. This report shows a summary of the evaluation activity and of the tendency analysis based on individual event analyzed in 2003. The tendency analysis was undertaken on about 1600 analyzed events, from the view point of Mechanics, Electrics, Instruments and Controls and Operations, about the causes, countermeasures, troubled equipments and the possible of lessons learnt from overseas events. This report is to show the whole tendency of overseas events and incidents for the improvement of the safety and reliability of domestic PWR plants. (author)

  2. Analysis of failure events for expansion joints in nuclear power plants

    Energy Technology Data Exchange (ETDEWEB)

    Sato, Masahiro [Institute of Nuclear Safety System Inc., Mihama, Fukui (Japan)

    2001-09-01

    Although a large number of expansion joints are used in nuclear power plants with light water reactors, their failure events have not been paid as much attention as those of vessels and pipes. However, as the operation period of nuclear power plants becomes longer, it is necessary to pay attention to their failure events as well as those of vessels and pipes, because aging problems and latent troubles originated in design or fabrication of expansion joints may appear during their long period operation. In this work, we investigated failure event reports of expansion joints in nuclear power plants both in Japan and in U.S.A. and analyzed (1) the influence to output power level, (2) the position and (3) the cause of each failure. It is revealed that the failure events of expansion joints have continuously occurred, some of which have exerted influence upon power level and have caused fatal or injury accidents of personnel, and hence the importance of corrective actions to prevent the recurrence of such events is pointed out. The importance of countermeasures to the following individual events is also pointed out: (1) corrosion of expansion joints in service water systems, (2) degradation of rubber expansion joints in main condensers, (3) vibration and fatigue of expansion joints in extraction steam lines and (4) transgranular stress corrosion cracking of penetration bellows of containments. (author)

  3. Canadian nuclear power principles for beyond design basis events - supporting rationale

    International Nuclear Information System (INIS)

    Elliott, M.; Newman, G.; Bhaloo, A.

    2014-01-01

    The development of the following principles and their rationale began during a special Chief Nuclear Engineers forum held on March 25th, 2013 in Toronto. These principles are intended to provide guidance to the Canadian Nuclear Power Industry in developing responses to the lessons learned from the Fukushima event of March 2011. These principles were accepted and signed off by the Chief Nuclear Officers of each of the three utilities in August 2013 and were presented to the CNSC at a public hearing on August 21, 2013. This document provides the underlying rationale for the principles. (author)

  4. A study on discrete event dynamic model for nuclear operations of main feed water pump

    International Nuclear Information System (INIS)

    Bae, J. C.; Choi, J. I.

    2000-01-01

    A major objective of the study is to propose a supervisory control algorithm based on the discrete event dynamic system (DEDS) model and apply it to the automation of nuclear operations. The study is motivated by the suitability of the DEDS model for simulation of man-made control action and the potential of the DEDS based supervisory control algorithm for enhanced licensibility, when implemented in nuclear plants, through design transparency due to strong analytic backgrounds. The DEDS model can analytically show the robust stability of the proposed supervisory controller providing design transparency for enhanced licensibility when implemented in nuclear operations

  5. Anatomy of event and human performance management in nuclear power plants

    International Nuclear Information System (INIS)

    Wang Jinhua

    2014-01-01

    This article analyzes the occurrence mechanism of events in nuclear power plants, and explains the four factors of human errors and the relations among them, then probes into the occurrence mechanism and characteristics of human errors in nuclear power plants. Moreover, the article clarifies that the principle of human performance training in nuclear power plants is all-member training, and that the implementation approach is to develop different human performance tools for different staff categories as workers, knowledge workers and supervisors, which are categorized based on characteristics of work of different staff. (author)

  6. Canadian nuclear power principles for beyond design basis events - supporting rationale

    Energy Technology Data Exchange (ETDEWEB)

    Elliott, M. [OPG Nuclear, Ontario (Canada); Newman, G. [Bruce Power, Ontario (Canada); Bhaloo, A. [New Brunswick Power, New Brunswick (Canada)

    2014-09-15

    The development of the following principles and their rationale began during a special Chief Nuclear Engineers forum held on March 25th, 2013 in Toronto. These principles are intended to provide guidance to the Canadian Nuclear Power Industry in developing responses to the lessons learned from the Fukushima event of March 2011. These principles were accepted and signed off by the Chief Nuclear Officers of each of the three utilities in August 2013 and were presented to the CNSC at a public hearing on August 21, 2013. This document provides the underlying rationale for the principles. (author)

  7. Canadian nuclear power principles for beyond design basis events - supporting rationale

    Energy Technology Data Exchange (ETDEWEB)

    Elliott, M. [Ontario Power Generation Nuclear, Pickering, ON (Canada); Newman, G. [Bruce Power, Tiverton, ON (Canada); Bhaloo, A. [New Brunswick Power, Fredericton, NB (Canada)

    2014-07-01

    The development of the following principles and their rationale began during a special Chief Nuclear Engineers forum held on March 25th, 2013 in Toronto. These principles are intended to provide guidance to the Canadian Nuclear Power Industry in developing responses to the lessons learned from the Fukushima event of March 2011. These principles were accepted and signed off by the Chief Nuclear Officers of each of the three utilities in August 2013 and were presented to the CNSC at a public hearing on August 21, 2013. This document provides the underlying rationale for the principles. (author)

  8. Nuclear and energies - synthesis of outstanding events from April 2011 to November 2011. No. 58/December 2011

    International Nuclear Information System (INIS)

    Lenail, Bernard; Ducroux, Guy; Lamorlette, Guy; Gollion, Jacques; Seyve, Claude; Robin, Jean-Pierre; Fromant, Bernard; Raisonnier, Daniele; Lepine, Gerard; Vandevoir, Roger

    2011-12-01

    While referring to recent events, the articles discuss and comment the evolution of the energy sector (perspectives in terms of energy mix), the current events in the field of renewable energies, the struggle against the greenhouse effect (Grenelle de l'Environnement, impact of the nuclear sector on the environment in France and in the world), the limited impact of the Fukushima accident on the uranium market, the nuclear fuel fabrication (reorganization of production lines by AREVA), the nuclear reactors (perspectives and events in the world, and in France for different sites), the relationship between the nuclear industry and the society (surveys, international issues, perception of nuclear safety)

  9. Root Cause Analysis Following an Event at a Nuclear Installation: Reference Manual

    International Nuclear Information System (INIS)

    2015-01-01

    Following an event at a nuclear installation, it is important to determine accurately its root causes so that effective corrective actions can be implemented. As stated in IAEA Safety Standards Series No. SF-1, Fundamental Safety Principles: “Processes must be put in place for the feedback and analysis of operating experience”. If this process is completed effectively, the probability of a similar event occurring is significantly reduced. Guidance on how to establish and implement such a process is given in IAEA Safety Standards Series No. NS-G-2.11, A System for the Feedback of Experience from Events in Nuclear Installations. To cater for the diverse nature of operating experience events, several different root cause analysis (RCA) methodologies and techniques have been developed for effective investigation and analysis. An event here is understood as any unanticipated sequence of occurrences that results in, or potentially results in, consequences to plant operation and safety. RCA is not a topic uniquely relevant to event investigators: knowledge of the concepts enhances the learning characteristics of the whole organization. This knowledge also makes a positive contribution to nuclear safety and helps to foster a culture of preventing event occurrence. This publication allows organizations to deepen their knowledge of these methodologies and techniques and also provides new organizations with a broad overview of the RCA process. It is the outcome of a coordinated effort involving the participation of experts from nuclear organizations, the energy industry and research centres in several Member States. This publication also complements IAEA Services Series No. 10, PROSPER Guidelines: Guidelines for Peer Review and for Plant Self- Assessment of Operational Experience Feedback Process, and is intended to form part of a suite of publications developing the principles set forth in these guidelines. In addition to the information and description of RCA

  10. Root Cause Analysis Following an Event at a Nuclear Installation: Reference Manual. Companion CD

    International Nuclear Information System (INIS)

    2015-01-01

    Following an event at a nuclear installation, it is important to determine accurately its root causes so that effective corrective actions can be implemented. As stated in IAEA Safety Standards Series No. SF-1, Fundamental Safety Principles: “Processes must be put in place for the feedback and analysis of operating experience”. If this process is completed effectively, the probability of a similar event occurring is significantly reduced. Guidance on how to establish and implement such a process is given in IAEA Safety Standards Series No. NS-G-2.11, A System for the Feedback of Experience from Events in Nuclear Installations. To cater for the diverse nature of operating experience events, several different root cause analysis (RCA) methodologies and techniques have been developed for effective investigation and analysis. An event here is understood as any unanticipated sequence of occurrences that results in, or potentially results in, consequences to plant operation and safety. RCA is not a topic uniquely relevant to event investigators: knowledge of the concepts enhances the learning characteristics of the whole organization. This knowledge also makes a positive contribution to nuclear safety and helps to foster a culture of preventing event occurrence. This publication allows organizations to deepen their knowledge of these methodologies and techniques and also provides new organizations with a broad overview of the RCA process. It is the outcome of a coordinated effort involving the participation of experts from nuclear organizations, the energy industry and research centres in several Member States. This publication also complements IAEA Services Series No. 10, PROSPER Guidelines: Guidelines for Peer Review and for Plant Self- Assessment of Operational Experience Feedback Process, and is intended to form part of a suite of publications developing the principles set forth in these guidelines. In addition to the information and description of RCA

  11. GC Side Event: Nuclear Energy Innovation and the Paris Agreement. Presentations

    International Nuclear Information System (INIS)

    2017-01-01

    This event presented roadmaps for nuclear energy innovation linked to nationally determined contributions (NDCs) to the global response to climate change. It covered enabling conditions for research and development, the regulatory framework and infrastructure to support Member States’ NDC updates from 2020 to 2050

  12. Assessment procedure and probability determination methods of aircraft crash events in siting for nuclear power plants

    International Nuclear Information System (INIS)

    Zheng Qiyan; Zhang Lijun; Huang Weiqi; Yin Qingliao

    2010-01-01

    Assessment procedure of aircraft crash events in siting for nuclear power plants, and the methods of probability determination in two different stages of prelimi- nary screening and detailed evaluation are introduced in this paper. Except for general air traffic, airport operations and aircraft in the corridor, the probability of aircraft crash by military operation in the military airspaces is considered here. (authors)

  13. Evaluation of PWR's operating experience. Significant events which influenced French nuclear power program

    International Nuclear Information System (INIS)

    Dupuis, M.C.

    1986-10-01

    This report discusses developments or changes in safety policy (whether statutory or otherwise) and in plant design and operation, which, in many cases, correlate. When considering these events, it is important to bear in mind the standardization policy characterizing the French nuclear power program, and implying central decision-making, both for the safety authorities and the operating utility [fr

  14. Basic Safety Considerations for Nuclear Power Plant Dealing with External Human Induced Events

    Energy Technology Data Exchange (ETDEWEB)

    Salem, W., E-mail: wafaasalem21@yahoo.com [Nuclear and Radiological Regulatory Authority (Egypt)

    2014-10-15

    Facilities and human activities in the region in which a nuclear power plant is located may under some conditions affect its safety. The potential sources of human induced events external to the plant should be identified and the severity of the possible resulting hazard phenomena should be evaluated to derive the appropriate design bases for the plant. They should also be monitored and periodically assessed over the lifetime of the plant to ensure that consistency with the design assumptions is maintained. External human induced events that could affect safety should be investigated in the site evaluation stage for every nuclear power plant site. The region is required to be examined for facilities and human activities that have the potential, under certain conditions, to endanger the nuclear power plant over its entire lifetime. Each relevant potential source is required to be identified and assessed to determine the potential interactions with personnel and plant items important to safety. (author)

  15. Investigations on human error hazards in recent unintended trip events of Korean nuclear power plants

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Sa Kil; Jang, Tong Il; Lee, Yong Hee; Shin, Kwang Hyeon [KAERI, Daejeon (Korea, Republic of)

    2012-10-15

    According to the Operational Performance Information System (OPIS) which has been operated to improve the public understanding by the KINS (Korea Institute of Nuclear Safety), unintended trip events by mainly human errors counted up to 38 cases (18.7%) from 2000 to 2011. Although the Nuclear Power Plant (NPP) industry in Korea has been making efforts to reduce the human errors which have largely contributed to trip events, the human error rate might keep increasing. Interestingly, digital based I and C systems is the one of the reduction factors of unintended reactor trips. Human errors, however, have occurred due to the digital based I and C systems because those systems require new or changed behaviors to the NPP operators. Therefore, it is necessary that the investigations of human errors consider a new methodology to find not only tangible behavior but also intangible behavior such as organizational behaviors. In this study we investigated human errors to find latent factors such as decisions and conditions in the all of the unintended reactor trip events during last dozen years. To find them, we applied the HFACS (Human Factors Analysis and Classification System) which is a commonly utilized tool for investigating human contributions to aviation accidents under a widespread evaluation scheme. The objective of this study is to find latent factors behind of human errors in nuclear reactor trip events. Therefore, a method to investigate unintended trip events by human errors and the results will be discussed in more detail.

  16. Investigations on human error hazards in recent unintended trip events of Korean nuclear power plants

    International Nuclear Information System (INIS)

    Kim, Sa Kil; Jang, Tong Il; Lee, Yong Hee; Shin, Kwang Hyeon

    2012-01-01

    According to the Operational Performance Information System (OPIS) which has been operated to improve the public understanding by the KINS (Korea Institute of Nuclear Safety), unintended trip events by mainly human errors counted up to 38 cases (18.7%) from 2000 to 2011. Although the Nuclear Power Plant (NPP) industry in Korea has been making efforts to reduce the human errors which have largely contributed to trip events, the human error rate might keep increasing. Interestingly, digital based I and C systems is the one of the reduction factors of unintended reactor trips. Human errors, however, have occurred due to the digital based I and C systems because those systems require new or changed behaviors to the NPP operators. Therefore, it is necessary that the investigations of human errors consider a new methodology to find not only tangible behavior but also intangible behavior such as organizational behaviors. In this study we investigated human errors to find latent factors such as decisions and conditions in the all of the unintended reactor trip events during last dozen years. To find them, we applied the HFACS (Human Factors Analysis and Classification System) which is a commonly utilized tool for investigating human contributions to aviation accidents under a widespread evaluation scheme. The objective of this study is to find latent factors behind of human errors in nuclear reactor trip events. Therefore, a method to investigate unintended trip events by human errors and the results will be discussed in more detail

  17. Analysis of internal events for the Unit 1 of the Laguna Verde nuclear power station

    International Nuclear Information System (INIS)

    Huerta B, A.; Aguilar T, O.; Nunez C, A.; Lopez M, R.

    1993-01-01

    This volume presents the results of the starter event analysis and the event tree analysis for the Unit 1 of the Laguna Verde nuclear power station. The starter event analysis includes the identification of all those internal events which cause a disturbance to the normal operation of the power station and require mitigation. Those called external events stay beyond the reach of this study. For the analysis of the Laguna Verde power station eight transient categories were identified, three categories of loss of coolant accidents (LOCA) inside the container, a LOCA out of the primary container, as well as the vessel break. The event trees analysis involves the development of the possible accident sequences for each category of starter events. Events trees by systems for the different types of LOCA and for all the transients were constructed. It was constructed the event tree for the total loss of alternating current, which represents an extension of the event tree for the loss of external power transient. Also the event tree by systems for the anticipated transients without scram was developed (ATWS). The events trees for the accident sequences includes the sequences evaluation with vulnerable nucleus, that is to say those sequences in which it is had an adequate cooling of nucleus but the remoting systems of residual heat had failed. In order to model adequately the previous, headings were added to the event tree for developing the sequences until the point where be solved the nucleus state. This process includes: the determination of the failure pressure of the primary container, the evaluation of the environment generated in the reactor building as result of the container failure or cracked of itself, the determination of the localization of the components in the reactor building and the construction of boolean expressions to estimate the failure of the subordinated components to an severe environment. (Author)

  18. INES: The International Nuclear and Radiological Event Scale User's Manual. 2008 Edition

    International Nuclear Information System (INIS)

    2009-05-01

    The International Nuclear and Radiological Event Scale is used for promptly and consistently communicating to the public the safety significance of events associated with sources of radiation. It covers a wide spectrum of practices, including industrial use such as radiography, use of radiation sources in hospitals, activities at nuclear facilities, and the transport of radioactive material. By putting events from all these practices into a proper perspective, use of INES can facilitate a common understanding between the technical community, the media and the public. The scale was developed in 1990 by international experts convened by the IAEA and the OECD Nuclear Energy Agency (OECD/NEA). It originally reflected the experience gained from the use of similar scales in France and Japan as well as consideration of possible scales in several countries. Since then, the IAEA has managed its development in cooperation with the OECD/NEA and with the support of more than 60 designated National Officers who officially represent the INES member States in the biennial technical meeting of INES. Initially the scale was applied to classify events at nuclear power plants, and then was extended and adapted to enable it to be applied to all installations associated with the civil nuclear industry. More recently, it has been extended and adapted further to meet the growing need for communication of the significance of all events associated with the transport, storage and use of radioactive material and radiation sources. This revised manual brings together the guidance for all uses into a single document. Events are classified on the scale at seven levels: Levels 4-7 are termed 'accidents' and Levels 1-3 'incidents'. Events without safety significance are classified as 'Below Scale/Level 0'. Events that have no safety relevance with respect to radiation or nuclear safety are not classified on the scale. For communication of events to the public, a distinct phrase has been

  19. Analysis of internal events for the Unit 1 of the Laguna Verde Nuclear Power Station. Appendixes

    International Nuclear Information System (INIS)

    Huerta B, A.; Lopez M, R.

    1995-01-01

    This volume contains the appendices for the accident sequences analysis for those internally initiated events for Laguna Verde Unit 1, Nuclear Power Plant. The appendix A presents the comments raised by the Sandia National Laboratories technical staff as a result of the review of the Internal Event Analysis for Laguna Verde Unit 1 Nuclear Power Plant. This review was performed during a joint Sandia/CNSNS multi-day meeting by the end 1992. Also included is a brief evaluation on the applicability of these comments to the present study. The appendix B presents the fault tree models printed for each of the systems included and.analyzed in the Internal Event Analysis for LVNPP. The appendice C presents the outputs of the TEMAC code, used for the cuantification of the dominant accident sequences as well as for the final core damage evaluation. (Author)

  20. Analysis of internal events for the Unit 1 of the Laguna Verde Nuclear Power Station. Appendixes

    International Nuclear Information System (INIS)

    Huerta B, A.; Lopez M, R.

    1995-01-01

    This volume contains the appendices for the accident sequences analysis for those internally initiated events for Laguna Verde Unit 1, Nuclear Power Plant. The appendix A presents the comments raised by the Sandia National Laboratories technical staff as a result of the review of the Internal Event Analysis for Laguna Verde Unit 1 Nuclear Power Plant. This review was performed during a joint Sandia/CNSNS multi-day meeting by the end 1992. Also included is a brief evaluation on the applicability of these comments to the present study. The appendix B presents the fault tree models printed for each of the systems included and analyzed in the Internal Event Analysis for LVNPP. The appendice C presents the outputs of the TEMAC code, used for the cuantification of the dominant accident sequences as well as for the final core damage evaluation. (Author)

  1. Evaluation of external hazards to nuclear power plants in the United States: Other external events

    International Nuclear Information System (INIS)

    Kimura, C.Y.; Prassinos, P.G.

    1989-02-01

    In support of implementation of the Nuclear Regulatory Commission's Severe Accident Policy, the Lawrence Livermore National Laboratory (LLNL) has performed a study of the risk of core damage to nuclear power plants in the United States due to ''other external events.'' The broad objective has been to gain an understanding of whether ''other external events'' (the hazards not covered by previous reports) are among the major potential accident initiators that may pose a threat of severe reactor core damage or of large radioactive release to the environment from the reactor. The ''other external events'' covered in this report are nearby industrial/military facility accidents, on site hazardous material storage accidents, severe temperature transients, severe weather storms, lightning strikes, external fires, extraterrestrial activity, volcanic activity, earth movement, and abrasive windstorms. The analysis was based on two figures-of-merit, one based on core damage frequency and the other based on the frequency of large radioactive releases. 37 refs., 8 tabs

  2. Trending of low level events and near misses to enhance safety performance in nuclear power plants

    International Nuclear Information System (INIS)

    2005-11-01

    The IAEA Safety Fundamentals publication, Safety of Nuclear Installations, Safety Series No. 110, states the need for operating organizations to establish a programme for the collection and analysis of operating experience in nuclear power plants. Such a programme ensures that operating experience is analysed, events important to safety are reviewed in depth, and lessons learned are disseminated to the staff of the organization and to relevant national and international organizations. As a result of the effort to enhance safety in operating organizations, incidents are progressively decreasing in number and significance. This means that in accordance with international reporting requirements the amount of collected data becomes less sufficient to draw meaningful statistical conclusions. This is where the collection and trend analysis of low level events and near misses can prove to be very useful. These trends can show which of the safety barriers are weak or failing more frequently. Evaluation and trending of low level events and near misses will help to prevent major incidents because latent weaknesses have been identified and corrective actions taken to prevent recurrence. This leads to improved safety and production. Low level events and near misses, which may reach several thousand per reactor operating year, need to be treated by the organizations as learning opportunities. A system for capturing these low level events and near misses truly needs to be an organization-wide system in which all levels of the organization, including contractors, participate. It is desirable that the overall operational experience feedback (OEF) process should integrate the lessons learned and the associated data from significant events with those of lower level events and near misses. To be able to effectively implement a process dealing with low level events and near misses, it is necessary that the organization have a well established OEF process for significant events

  3. Contingencies of Value

    DEFF Research Database (Denmark)

    Strandvad, Sara Malou

    2014-01-01

    Based on a study of the admission test at a design school, this paper investigates the contingencies of aesthetic values as these become visible in assessment practices. Theoretically, the paper takes its starting point in Herrnstein Smith’s notion of ‘contingencies of values’ and outlines...... a pragmatist ground where cultural sociology and economic sociology meet. Informed by the literature on cultural intermediaries, the paper discusses the role of evaluators and the devices which accompany them. Whereas studies of cultural intermediaries traditionally apply a Bourdieusian perspective, recent......, the paper does not accept this storyline. As an alternative, the paper outlines the contingencies of values which are at play at the admission test, composed of official assessment criteria and scoring devices together with conventions within the world of design, and set in motion by interactions...

  4. Meteorological events in site evaluation for nuclear power plants. Safety guide

    International Nuclear Information System (INIS)

    2005-01-01

    This Safety Guide provides recommendations and guidance on conducting hazard assessments of extreme and rare meteorological phenomena. It is of interest to safety assessors and regulators involved in the licensing process as well as to designers of nuclear power plants. This Safety Guide was prepared under the IAEA programme for safety standards for nuclear power plants. It supplements the IAEA Safety Requirements publication on Site Evaluation for Nuclear Facilities which is to supersede the Code on the Safety of Nuclear Power Plants: Siting, Safety Series No. 50-C-S (Rev. 1), IAEA, Vienna (1988). The present Safety Guide supersedes two earlier Safety Guides: Safety Series No. 50-SG-S11A (1981) on Extreme Meteorological Events in Nuclear Power Plant Siting, Excluding Tropical Cyclones and Safety Series No. 50-SG-S11B (1984) on Design Basis Tropical Cyclone for Nuclear Power Plants. The purpose of this Safety Guide is to provide recommendations and guidance on conducting hazard assessments of extreme and rare meteorological phenomena. This Safety Guide provides interpretation of the Safety Requirements publication on Site Evaluation for Nuclear Facilities and guidance on how to fulfil these requirements. It is aimed at safety assessors or regulators involved in the licensing process as well as designers of nuclear power plants, and provides them with guidance on the methods and procedures for analyses that support the assessment of the hazards associated with extreme and rare meteorological events. This Safety Guide discusses the extreme values of meteorological variables and rare meteorological phenomena, as well as their rates of occurrence, according to the following definitions: (a) Extreme values of meteorological variables such as air temperature and wind speed characterize the meteorological or climatological environment. And (b) Rare meteorological phenomena

  5. Standard format and content of a licensee physical protection plan for strategic special nuclear material in transit - April 1980

    International Nuclear Information System (INIS)

    Anon.

    1981-01-01

    A predetermined plan to respond to safeguards contingency events is required to be prepared, based on personnel and other physical protection resources described in the Physical Protection Plan for strategic special nuclear material (SSNM) in transit. Specific requirements for the contingency plan are provided in Appendix C. Licensee Safeguards Contingency Plans, to 10 CFR Part 73. Regulatory Guide 5.56, Standard Format and Content of Safeguards Contingency Plans for Transportation, provides guidance for the preparation of transportation contingency plans. Licensee is reminded that all three submissions - the Physical Protection Plan, the Physical Protection Arrangements for Specific Shipments, and the Safeguards Contingency Plan - together describe the system for physical protection of each particular shipment. They should be developed and maintained to be completely consistent with each other for each shipment

  6. External Events Excluding Earthquakes in the Design of Nuclear Power Plants. Safety Guide

    International Nuclear Information System (INIS)

    2008-01-01

    This Safety Guide provides recommendations and guidance on design for the protection of nuclear power plants from the effects of external events (excluding earthquakes), i.e. events that originate either off the site or within the boundaries of the site but from sources that are not directly involved in the operational states of the nuclear power plant units. In addition, it provides recommendations on engineering related matters in order to comply with the safety objectives and requirements established in the IAEA Safety Requirements publication, Safety of Nuclear Power Plants: Design. It is also applicable to the design and safety assessment of items important to the safety of land based stationary nuclear power plants with water cooled reactors. Contents: 1. Introduction; 2. Application of safety criteria to the design; 3. Design basis for external events; 4. Aircraft crash; 5. External fire; 6. Explosions; 7. Asphyxiant and toxic gases; 8. Corrosive and radioactive gases and liquids; 9. Electromagnetic interference; 10. Floods; 11. Extreme winds; 12. Extreme meteorological conditions; 13. Biological phenomena; 14. Volcanism; 15. Collisions of floating bodies with water intakes and UHS components; Annex I: Aircraft crashes; Annex II: Detonation and deflagration; Annex III: Toxicity limits.

  7. Internal event analysis of Laguna Verde Unit 1 Nuclear Power Plant. System Analysis

    International Nuclear Information System (INIS)

    Huerta B, A.; Aguilar T, O.; Nunez C, A.; Lopez M, R.

    1993-01-01

    The Level 1 results of Laguna Verde Nuclear Power Plant PRA are presented in the I nternal Event Analysis of Laguna Verde Unit 1 Nuclear Power Plant , CNSNS-TR-004, in five volumes. The reports are organized as follows: CNSNS-TR-004 Volume 1: Introduction and Methodology. CNSNS-TR-004 Volume 2: Initiating Event and Accident Sequences. CNSNS-TR-004 Volume 3: System Analysis. CNSNS-TR-004 Volume 4: Accident Sequence Quantification and Results. CNSNS-TR-004 Volume 5: Appendices A, B and C. This volume presents the results of the system analysis for the Laguna Verde Unit 1 Nuclear Power Plant. The system analysis involved the development of logical models for all the systems included in the accident sequence event tree headings, and for all the support systems required to operate the front line systems. For the Internal Event analysis for Laguna Verde, 16 front line systems and 5 support systems were included. Detailed fault trees were developed for most of the important systems. Simplified fault trees focusing on major faults were constructed for those systems that can be adequately represent,ed using this kind of modeling. For those systems where fault tree models were not constructed, actual data were used to represent the dominant failures of the systems. The main failures included in the fault trees are hardware failures, test and maintenance unavailabilities, common cause failures, and human errors. The SETS and TEMAC codes were used to perform the qualitative and quantitative fault tree analyses. (Author)

  8. Safety at basic nuclear facilities other than nuclear power plants. Lessons learned from significant events reported in 2011 and 2012

    International Nuclear Information System (INIS)

    2014-01-01

    The third report on the safety of basic nuclear installations in France other than power reactors presents an IRSN's analysis of significant events reported to the Nuclear Safety Authority in the years 2011 and 2012. It covers plants, laboratories, research reactors and facilities for the treatment, storage or disposal of waste. This report aims to contribute to a better understanding by stakeholders and more widely by the public of the safety and radiation protection issues associated with the operation of nuclear facilities, the progress made in terms of safety as well as the identified deficiencies. The main trend shows, once again, the significant role of organizational and human factors in the significant events that occurred in 2011 and 2012, of which the vast majority are without noteworthy consequences. Aging mechanisms are another major cause of equipment failure and require special attention. The report also provides IRSN's analysis of specific events that are particularly instructive for facility safety and a synthesis of assessments performed by IRSN on topics that are important for safety and radiation protection. IRSN also includes an overview of its analysis of measures proposed by licensees for increasing the safety of their facilities after the March 2011 accident at the Fukushima Daiichi nuclear power plant in Japan, which consist of providing a 'hardened safety core' to confront extreme situations (earthquake, flooding, etc.) that are unlikely but plausible and can bring about levels of hazards higher than those taken into account in the design of the facilities

  9. Bridging the gap between event-by-event fluctuation measurements and theory predictions in relativistic nuclear collisions

    Energy Technology Data Exchange (ETDEWEB)

    Braun-Munzinger, P., E-mail: p.braun-munzinger@gsi.de [Extreme Matter Institute EMMI, GSI, Darmstadt (Germany); Physikalisches Institut, Universität Heidelberg, Heidelberg (Germany); Rustamov, A., E-mail: a.rustamov@cern.ch [Physikalisches Institut, Universität Heidelberg, Heidelberg (Germany); National Nuclear Research Center, Baku (Azerbaijan); Stachel, J., E-mail: stachel@physi.uni-heidelberg.de [Physikalisches Institut, Universität Heidelberg, Heidelberg (Germany)

    2017-04-15

    We develop methods to deal with non-dynamical contributions to event-by-event fluctuation measurements of net-particle numbers in relativistic nuclear collisions. These contributions arise from impact parameter fluctuations and from the requirement of overall net-baryon number or net-charge conservation and may mask the dynamical fluctuations of interest, such as those due to critical endpoints in the QCD phase diagram. Within a model of independent particle sources we derive formulae for net-particle fluctuations and develop a rigorous approach to take into account contributions from participant fluctuations in realistic experimental environments and at any cumulant order. Interestingly, contributions from participant fluctuations to the second and third cumulants of net-baryon distributions are found to vanish at mid-rapidity for LHC energies while higher cumulants of even order are non-zero even when the net-baryon number at mid-rapidity is zero. At lower beam energies the effect of participant fluctuations increases and induces spurious higher moments. The necessary corrections become large and need to be carefully taken into account before comparison to theory. We also provide a procedure for selecting the optimal phase–space coverage of particles for fluctuation analyses and discuss quantitatively the necessary correction due to global charge conservation.

  10. Appendix F - Sample Contingency Plan

    Science.gov (United States)

    This sample Contingency Plan in Appendix F is intended to provide examples of contingency planning as a reference when a facility determines that the required secondary containment is impracticable, pursuant to 40 CFR §112.7(d).

  11. History of Fire Events in the U.S. Commercial Nuclear Industry

    International Nuclear Information System (INIS)

    Bijan Najafi; Joglar-Biloch, Francisco; Kassawara, Robert P.; Khalil, Yehia

    2002-01-01

    Over the past decade, interest in performance-based fire protection has increased within the nuclear industry. In support of this growing interest, in 1997 the Electric Power Research Institute (EPRI) developed a long-range plan to develop/improve data and tools needed to support Risk-Informed/Performance-Based fire protection. This plan calls for continued improvement in collection and use of information obtained from fire events at nuclear plants. The data collection process has the objectives of improving the insights gained from such data and reducing the uncertainty in fire risk and fire modeling methods in order to make them a more reliable basis for performance based fire protection programs. In keeping with these objectives, EPRI continues to collect, review and analyze fire events in support of the nuclear industry. EPRI collects these records in cooperation with the Nuclear Electric Insurance Limited (NEIL), by compiling public fire event reports and by direct solicitation of U.S. nuclear facilities. EPRI fire data collection project is based on the principle that the understanding of history is one of the cornerstones of improving fire protection technology and practice. Therefore, the goal has been to develop and maintain a comprehensive database of fire events with flexibility to support various aspects of fire protection engineering. With more than 1850 fire records over a period of three decades and 2400 reactor years, this is the most comprehensive database of nuclear power industry fire events in existence today. In general, the frequency of fires in the U.S. commercial nuclear industry remains constant. In few cases, e.g., transient fires and fires in BWR offgas/recombiner systems, where either increasing or decreasing trends are observed, these trends tend to slow after 1980. The key issues in improving quality of the data remain to be consistency of the recording and reporting of fire events and difficulties in collection of records. EPRI has

  12. Computer simulation of nuclear pollutant diffusion from Shimane nuclear power plants and development of an evacuation strategy in the event of a nuclear incident

    International Nuclear Information System (INIS)

    Yakura, Haruna; Kurimasa, Akihiro

    2012-01-01

    Beginning from Tohoku (northeastern) Earthquake on March 11, an accident at the Fukushima Dai-ichi Nuclear Power Plant resulted in a substantial release of radioactivity to the environment. The accident forced a large number of residents to evacuate from surrounding areas. Moreover, the nuclear incident was life-threatening for the elderly and for people with serious illnesses who were confined in hospital or nursing homes. Strikingly, the causes of death were not directly attributed to radiation exposure but to problems encountered during evacuation. Using nuclear diffusion data from the Fukushima incident, we simulated nuclear pollutant dispersion using computer software A2C in an area of Tottori and Shimane Prefectures surrounding the Shimane Nuclear Power Plant. We generated a model for the spread of nuclear pollutants around the Emergency Planning Zone, id est (i.e.) EPZ. From these findings, we proposed evacuation strategies for residents near the power plant to ensure a safe and reliable escape from nuclear pollutants. Our recommendations include: immediate evacuation from PAZ area (within 5 km), securing indoor shelter in the area of the UPZ (from 5 km to 30 km) and preparations to evacuate further outwards from the nuclear plant site, daytime evacuation within a 30 km area after considering wind direction and velocity, and preparation of a planned evacuation strategy that identifies secure facilities for weaker people in the event of a disaster. (author)

  13. Disruptive event uncertainties in a perturbation approach to nuclear waste repository risk analysis

    Energy Technology Data Exchange (ETDEWEB)

    Harvey, T.F.

    1980-09-01

    A methodology is developed for incorporating a full range of the principal forecasting uncertainties into a risk analysis of a nuclear waste repository. The result of this methodology is a set of risk curves similar to those used by Rasmussen in WASH-1400. The set of curves is partially derived from a perturbation approach to analyze potential disruptive event sequences. Such a scheme could be useful in truncating the number of disruptive event scenarios and providing guidance to those establishing data-base development priorities.

  14. Contingent valuation and incentives

    Science.gov (United States)

    Patricia A. Champ; Nicholas E. Flores; Thomas C. Brown; James Chivers

    2002-01-01

    We empirically investigate the effect of the payment mechanism on contingent values by asking a willingness-to-pay question with one of three different payment mechanisms: individual contribution, contribution with provision point, and referendum. We find statistical evidence of more affirmative responses in the referendum treatment relative to the individual...

  15. Estimation of full moment tensors, including uncertainties, for earthquakes, volcanic events, and nuclear explosions

    Science.gov (United States)

    Alvizuri, Celso R.

    rather the confidence, is then given by the 'confidence curve' P( V), where P(V) is the probability that the true moment tensor for the event lies within the neighborhood of M that has fractional volume V. The area under the confidence curve provides a single, abbreviated 'confidence parameter' for M0. We apply the method to data from events in different regions and tectonic settings: 63 small (M w 4) earthquakes in the southern Alaska subduction zone, and 12 earthquakes and 17 nuclear explosions at the Nevada Test Site. Characterization of moment tensor uncertainties puts us in better position to discriminate among moment tensor source types and to assign physical processes to the events.

  16. Use of PSA for the analysis of operational events in nuclear power plants

    International Nuclear Information System (INIS)

    Hulsmans, M.

    2006-01-01

    An operational event is a safety-relevant incident that occurred in an industrial installation like a nuclear power plant (NPP). The probabilistic approach to event analysis focuses on the potential consequences of an operational event. Within its scope of application, it provides a quantitative assessment of the risk significance of this event (and similar events): it calculates the risk increase induced by the event. Such analyses may result in a more objective and a more accurate event severity measure than those provided by commonly used qualitative methods. Probabilistic event analysis complements the traditional event analysis approaches that are oriented towards the understanding of the (root) causes of an event. In practice, risk-based precursor analysis consists of the mapping of an operational event on a risk model of the installation, such as a probabilistic safety analysis (PSA) model. Precursor analyses result in an objective risk ranking of safety-significant events, called accident precursors. An unexpectedly high (or low) risk increase value is in itself already an important finding. This assessment also yields a lot of information on the structure of the risk, since the underlying dominant factors can easily be determined. Relevant 'what if' studies on similar events and conditions can be identified and performed (which is generally not considered in conventional event analysis), with the potential to yield even broader findings. The findings of such a structured assessment can be used for other purposes than merely risk ranking. The operational experience feedback process can be improved by helping to identify design measures and operational practices in order to prevent re-occurrence or in order to mitigate future consequences, and even to evaluate their expected effectiveness, contributing to the validation and prioritization of corrective measures. Confirmed and re-occurring precursors with correlated characteristics may point out opportunities

  17. Trend analyses of the emergency diesel generator problem events in Japanese and U.S. nuclear power plants

    International Nuclear Information System (INIS)

    Shimada, Yoshio

    2011-01-01

    Up to 2009, the author and a colleague conducted trend analyses of problem events related to main generators, emergency diesel generators, breakers, motors and transformers which are more likely to cause problems than other electric components in nuclear power plants. Among the electric components with high frequency of defect occurrence, i.e., emergency diesel generators, several years have passed since the last analyses. These are very important components needed to stop a nuclear reactor safely and to cool it down during external power supply loses. Then trend analyses were conducted for the second time. The trend analyses were performed on 80 problem events with emergency diesel generators which had occurred in U.S. nuclear power plants in the five years from 2005 through 2009 among events reported in the Licensee Event Reports (LERs: event reports submitted to NRC by U.S. nuclear power plants) which have been registered in the nuclear information database of the Institute of Nuclear Safety System, Inc. (INSS) , as well as 40 events registered in the Nuclear Information Archives (NUCIA), which occurred in Japanese nuclear power plants in the same time period. It was learned from the trend analyses of the problem events with emergency diesel generators that frequency of defect occurrence are high in both Japanese and US plants during plant operations and functional tests (that is, defects can be discovered effectively in advance), so that implementation of periodical functional tests under plant operation is an important task for the future. (author)

  18. Supervisory Styles: A Contingency Framework

    Science.gov (United States)

    Boehe, Dirk Michael

    2016-01-01

    While the contingent nature of doctoral supervision has been acknowledged, the literature on supervisory styles has yet to deliver a theory-based contingency framework. A contingency framework can assist supervisors and research students in identifying appropriate supervisory styles under varying circumstances. The conceptual study reported here…

  19. Contingency diagrams as teaching tools

    OpenAIRE

    Mattaini, Mark A.

    1995-01-01

    Contingency diagrams are particularly effective teaching tools, because they provide a means for students to view the complexities of contingency networks present in natural and laboratory settings while displaying the elementary processes that constitute those networks. This paper sketches recent developments in this visualization technology and illustrates approaches for using contingency diagrams in teaching.

  20. On-site habitability in the event of an accident at a nuclear facility

    International Nuclear Information System (INIS)

    1989-01-01

    This publication is intended to provide technical guidance and a methodology for regulatory bodies, designers, constructors and operators of nuclear facilities to assist them in assessing the current situation as regards on-site habitability for their specific nuclear facilities. Initially, the aim will be to ensure that the ''vital areas'' of the facility which are necessary for the safe operation and shutdown of the facility will remain habitable, in some cases continuously and in others transiently, in the event of an accident inside or outside the installation. The assessment procedure can be used not only for potential radiation accidents but also to consider the effects on habitability of those probable non-radiological events which, if not correctly and effectively countered, could lead to the development of potentially unsafe conditions in the facility itself. 30 refs, 4 figs, 8 tabs

  1. Dating the age of a recent nuclear event by gamma-spectrometry

    International Nuclear Information System (INIS)

    Nir-El, Y.

    2006-01-01

    The age of a recent, i.e., fresh, nuclear event can be determined by measuring the activity of short-lived parent and daughter fission products. The event studied was a short irradiation, of a small sample of uranium, in a nuclear reactor. Two clocks were investigated, 92 Sr- 92 Y and 135 I- 135 Xe. Measurements of the source by gamma-spectrometry yielded very good agreement between true and measured ages. The upper and lower age limits of applicability for the clocks in question were defined. The half-life of 92 Sr was found 2.635±0.008 hours and of 135 I 6.65±0.04 hours. (author)

  2. A Recent Revisit Study on the Human Error Events of Nuclear Facilities in Korea

    International Nuclear Information System (INIS)

    Lee, Y.-H.

    2016-01-01

    After Fukushima accident we have launched two new projects in Korea. One is for the development of the countermeasures for human errors in nuclear facilities, and the other is for the safety culture of nuclear power plant itself. There had happened several succeeding events that turned out to be the typical flags of the human and organizational factor issues for the safety of the other socio-technical systems as well as nuclear power plants in Korea. The second safety culture project was an ambitious development to establish an infra system utilising system dynamics, business process modeling and big-data techniques to provide effective and efficient information basis to various interest parties related to the nuclear power plants. However the project has been drastically cancelled last year without any further discussion on the original issues raised before in Korea. It may come not only from the conflicting perspectives among the different approaches to nuclear safety culture but also from the misunderstandings on the human factors for the nuclear safety.

  3. A multiprocessor system for the analysis of pictures of nuclear events

    CERN Document Server

    Bacilieri, P; Matteuzzi, P; Sini, G P; Zanotti, U

    1979-01-01

    The pictures of nuclear events obtained from the bubble chambers such as Gargamelle and BEBC at CERN and others from Serpukhov are geometrically processed at CNAF (Centro Nazionale Analysis Photogrammi) in Bologna. The analysis system includes an Erasme table and a CRT flying spot digitizer. The difficulties connected with the pictures of the four stereoscopic views of the bubble chambers are overcome by the choice of a strong interactive system. (0 refs).

  4. Development of BWR [boiling water reactor] and PWR [pressurized water reactor] event descriptions for nuclear facility simulator training

    International Nuclear Information System (INIS)

    Carter, R.J.; Bovell, C.R.

    1987-01-01

    A number of tools that can aid nuclear facility training developers in designing realistic simulator scenarios have been developed. This paper describes each of the tools, i.e., event lists, events-by-competencies matrices, and event descriptions, and illustrates how the tools can be used to construct scenarios

  5. Zero Time of Transitory Nuclear Events Derived by Parent-Daughter Systems

    International Nuclear Information System (INIS)

    Nir-El, Y.

    2014-01-01

    The detection and identification of a nuclear event that results in the dissemination of radioactive products into the environment can be realized by dating the age of the event. In order to correct observed activities for the decay since the occurrence of the event, the age must be known to a high level of confidence. Previous papers. described the method to date the age of a nuclear event by measuring the activity of two fission products, which constitute the clock in this application. Within the proficiency test programme for radionuclide laboratories supporting the CTBT, a simulated gamma spectrum with the characteristics of an atmospheric test of a Chinese thermonuclear device, was used to determine the zero time by calculating the theoretical peak area ratio of 95Nb/95Zr. Their approach used only the main gamma lines at 766 and 757 keV and assigned the same detection efficiency to both these close lines. Their methodology of calculating the uncertainty of zero time is subject to comments because it takes the sum of two components (nuclide ratio and activity ratio as function of time) in quadrature. In another paper, the activity of 95Nb as a function of time was presented without any development or expression for the zero time. Analytical equations for zero time and the associated uncertainty calculations were derived in a recent paper using a measured activity ratio of two nuclides and illustrating the procedure by data from the Chinese test. The evaluation of the zero time uncertainty was performed by a very large set of very complicated analytical equations. The present paper aims at developing a procedure to determine the zero time and its uncertainty in a transitory nuclear event by treating a parent-daughter system of 3 nuclides, where one daughter feeds the other one, in addition to its direct feeding by the decay of the parent

  6. Internal event analysis for Laguna Verde Unit 1 Nuclear Power Plant. Accident sequence quantification and results

    International Nuclear Information System (INIS)

    Huerta B, A.; Aguilar T, O.; Nunez C, A.; Lopez M, R.

    1994-01-01

    The Level 1 results of Laguna Verde Nuclear Power Plant PRA are presented in the I nternal Event Analysis for Laguna Verde Unit 1 Nuclear Power Plant, CNSNS-TR 004, in five volumes. The reports are organized as follows: CNSNS-TR 004 Volume 1: Introduction and Methodology. CNSNS-TR4 Volume 2: Initiating Event and Accident Sequences. CNSNS-TR 004 Volume 3: System Analysis. CNSNS-TR 004 Volume 4: Accident Sequence Quantification and Results. CNSNS-TR 005 Volume 5: Appendices A, B and C. This volume presents the development of the dependent failure analysis, the treatment of the support system dependencies, the identification of the shared-components dependencies, and the treatment of the common cause failure. It is also presented the identification of the main human actions considered along with the possible recovery actions included. The development of the data base and the assumptions and limitations in the data base are also described in this volume. The accident sequences quantification process and the resolution of the core vulnerable sequences are presented. In this volume, the source and treatment of uncertainties associated with failure rates, component unavailabilities, initiating event frequencies, and human error probabilities are also presented. Finally, the main results and conclusions for the Internal Event Analysis for Laguna Verde Nuclear Power Plant are presented. The total core damage frequency calculated is 9.03x 10-5 per year for internal events. The most dominant accident sequences found are the transients involving the loss of offsite power, the station blackout accidents, and the anticipated transients without SCRAM (ATWS). (Author)

  7. Radiodosimetry and preventive measures in the event of a nuclear accident. Proceedings of an international symposium

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-08-01

    An international symposium on Radiodosimetry and Preventive Measures in the Event of a Nuclear Accident was held in Cracow, Poland, from 26 to 28 May 1994. The symposium was organized by the Polish Society for Nuclear Medicine, and co-sponsored by the IAEA. Over 40 experts from Belarus, Latvia, Lithuania, Germany, Poland, the Russian Federation, Sweden and Switzerland participated. The aim of the Symposium was to review models of iodine kinetics used in the calculation of internal radiation doses to the thyroid after the Chernobyl accident, to discuss internal and external radiation dose to the thyroid in terms or risk of thyroid cancer, and to present data on the incidence rate of thyroid cancer in the selected iodine deficient area in Poland. A part of the symposium was dedicated to the physiological basis of iodine prophylaxis and emergency planning for a nuclear accident. Recommendations of the IAEA on preventive measures in the event of a nuclear accident were also addressed. These proceedings contain the full text of the eight invited papers presented at the symposium. Refs, figs, tabs.

  8. Radiodosimetry and preventive measures in the event of a nuclear accident. Proceedings of an international symposium

    International Nuclear Information System (INIS)

    1996-08-01

    An international symposium on Radiodosimetry and Preventive Measures in the Event of a Nuclear Accident was held in Cracow, Poland, from 26 to 28 May 1994. The symposium was organized by the Polish Society for Nuclear Medicine, and co-sponsored by the IAEA. Over 40 experts from Belarus, Latvia, Lithuania, Germany, Poland, the Russian Federation, Sweden and Switzerland participated. The aim of the Symposium was to review models of iodine kinetics used in the calculation of internal radiation doses to the thyroid after the Chernobyl accident, to discuss internal and external radiation dose to the thyroid in terms or risk of thyroid cancer, and to present data on the incidence rate of thyroid cancer in the selected iodine deficient area in Poland. A part of the symposium was dedicated to the physiological basis of iodine prophylaxis and emergency planning for a nuclear accident. Recommendations of the IAEA on preventive measures in the event of a nuclear accident were also addressed. These proceedings contain the full text of the eight invited papers presented at the symposium. Refs, figs, tabs

  9. OVERVIEW OF THE ACTIVITIES OF THE NUCLEAR ENERGY AGENCY WORKING GROUP ON EXTERNAL EVENTS

    Energy Technology Data Exchange (ETDEWEB)

    Nakoski, John A.; Smith, Curtis L.; Kim, Min Kyu

    2016-10-01

    The Orgranisation for Economic Cooperation and Development (OECD) Nuclear Energy Agency (NEA) has established a Working Group on External Events (WGEV) that provides a forum for subject matter experts from the nuclear industry and regulators to improve the understanding and treatment of external hazards that would support the continued safety performance of nuclear installations, and improve the effectiveness of regulatory practices, in NEA member countries. This report provides a description of the ongoing work of the WGEV. The work of the WGEV includes the collection of information and conducting a workshop on severe weather and storm surge that brought together a diverse group of subject matter experts to identify commendable practices related to the treatment of severe weather and storm surge consideration in regulatory and operational decision-making. Other work of the WGEV includes looking at science-based screening of external events that are factored into decisions on the safe operation of nuclear facilities; and identification of commendable practices and knowledge gaps on riverine flooding.

  10. Power plant construction lead times: The value of contingency planning

    International Nuclear Information System (INIS)

    Rubin, L.J.

    1985-01-01

    In this paper an analysis of two different approaches to the construction of a major power plant (nuclear) is presented. The analysis compares an accelerated, ''go-for-broke'' strategy-which has some risk of being delayed-with a more deliberate contingency construction schedule in terms of revenue requirements and costs of electricity. It is demonstrated that under a wide variety of circumstances there are important advantages to the contingency strategy, but that the magnitude of those advantages is sensitive to the character of the power system being examined and to the flexibility of the contingency approach

  11. External man-induced events in relation to nuclear power plant design

    International Nuclear Information System (INIS)

    1982-01-01

    This Guide deals with the basic design requirements for nuclear power plants, and presents a general design approach for protection against the effects of man-induced events. Section 2 discusses the general design approach. Section 3 outlines the development of the basic information necessary for an evaluation of the adequacy of a design against the effects of aircraft crashes, fires, explosions, and the release of toxic gases or corrosive substances. Section 4 outlines the design logic for protection against external man-induced events. It indicates possible methods of ensuring overall plant safety, including protection against possible secondary effects. Included for each event are: a methodology for calculating the design input parameters from the data generated in the siting study, system protection considerations from the effects of this man-induced event, and criteria for judging the adequacy of the protection provided. Specific design guidance related to acts of sabotage is not provided in this Guide. It should be recognized, however, that for certain situations such acts can be important to safety and could constitute the controlling postulated initiating event for design. The list of events covered is not necessarily complete. However, important events on which enough work has already been done in various Member States to enable their effects to be converted into generally accepted design parameters are included. In addition, other man-induced events such as dam ruptures, ship collisions, construction accidents and the like are identified but no general guidelines for design can be specified for these at present. These events need to be considered on an ad hoc basis, in order to arrive at design input parameters for them

  12. Low Level Event and Near Miss Process for Nuclear Power Plants: Best Practices

    International Nuclear Information System (INIS)

    2012-01-01

    The IAEA programme on the operational safety of nuclear power plants gives priority to the development and promotion of the proper use of IAEA safety standards through the provision of assistance to Member States in the application of safety standards, the performance of safety review missions and the conduct of training activities based on safety standards. A number of IAEA safety standards and nuclear safety publications discuss the processes that need to be put into place for the feedback and analysis of operating experience (OE) at nuclear power plants. These include: Fundamental Safety Principles (IAEA Safety Standards Series No. SF-1), Safety of Nuclear Power Plants: Commissioning and Operation (IAEA Safety Standards Series No. SSR-2/2), Application of the Management System for Facilities and Activities (IAEA Safety Standards Series No. GS-G-3.1) and A System for the Feedback of Experience from Events in Nuclear Installations (IAEA Safety Standards Series No. NS-G-2.11). Additionally, several IAEA TECDOCs cover many aspects of the establishment, conduct and continuous improvement of an OE programme at nuclear power plants, including the consideration of low level events (LLEs) and near misses (NMs). Although these IAEA safety standards and nuclear safety publications have been in existence for several years, 70 per cent of the IAEA Operational Safety Review Team (OSART) missions carried out at nuclear power plants between 2006 and 2010 identified weaknesses in the reporting and analysis process for LLEs and NMs. In fact, this has been one of the recurring issues most often identified in the area of OE during these missions. These weaknesses have been further confirmed by most of the IAEA Peer Review of the Operational Safety Performance Experience (PROSPER) missions that have been conducted to date. Finally, the IAEA International Nuclear Safety Group, in their report entitled Improving the International System for Operating Experience Feedback (INSAG-23

  13. Event classification related to overflow of solvent containing uranium according to the INES scale (International Nuclear and Radiological Event Scale); Classificacao do evento de transbordamento de solvente contendo uranio segundo a escala INES (International Nuclear and Radiological Event Scale)

    Energy Technology Data Exchange (ETDEWEB)

    Dourado, Eneida R.G.; Assis, Juliana T. de; Lage, Ricardo F., E-mail: cneida@inb.gov.br, E-mail: julianateixeira@inb.gov.br, E-mail: rlage@inb.gov.br [lndustrias Nucleares do Brasil S/A (CLISE.P/INB), Rio de Janeiro, RJ (Brazil). Coordenacao de Licenciamento Nuclear e Ambiental, Saude e Seguranca; Lopes, Karina B., E-mail: karina@inb.gov.br [lndustrias Nucleares do Brasil S/A (CPRAD/INB), Rio de Janeiro, RJ (Brazil). Coordenacao de Protecao Radiologica

    2013-11-01

    This paper aims to frame the event overflow organic solvent rich in uranium, from a decanter of ore beneficiation plant, caused by the fall in the supply of electricity, according to the criteria established by the International Nuclear Event Scale and radiological (INES), facilitating the understanding of the occurrence and communication with the public regarding the radiation safety aspects involved. With the fall of electricity, routine procedures in situations of installation stop were performed, however, due to operational failure, the valve on the transfer line liquor was not closed. Thus, the mixer continued being fed with liquor, that led the consequent leakage of solvent loaded with uranium. It reached the drainage system, and the box of rainwater harvesting of the plant. However, immediately after the detection of the event, corrective actions were initiated and the overflow was contained. Regulatory agencies followed the removal of the solvent and on the results of the analysis of environmental monitoring, found that the event did not provide exposure to workers or any other impact. Therefore, comparing the characteristics of the event and the guidelines proposed by the INES scale, it is concluded that the classification of the event is below scale/level 0, confirming the absence of risk to the local population, workers and the environment.

  14. Contingency and similarity in response selection.

    Science.gov (United States)

    Prinz, Wolfgang

    2018-05-09

    This paper explores issues of task representation in choice reaction time tasks. How is it possible, and what does it take, to represent such a task in a way that enables a performer to do the task in line with the prescriptions entailed in the instructions? First, a framework for task representation is outlined which combines the implementation of task sets and their use for performance with different kinds of representational operations (pertaining to feature compounds for event codes and code assemblies for task sets, respectively). Then, in a second step, the framework is itself embedded in the bigger picture of the classical debate on the roles of contingency and similarity for the formation of associations. The final conclusion is that both principles are needed and that the operation of similarity at the level of task sets requires and presupposes the operation of contingency at the level of event codes. Copyright © 2018 The Author. Published by Elsevier Inc. All rights reserved.

  15. Technical organization of safety authorities for the event of an accident at a nuclear installation

    International Nuclear Information System (INIS)

    Scherrer, J.; Evrard, J.M.; Ney, J.

    1986-01-01

    Within the general context of nuclear safety, the Central Nuclear Installation Safety Service of the French Ministry for Industry and its technical backup, the Institute for Radiation Protection and Nuclear Safety of the CEA (Atomic Energy Commission), have established a special organization designed to provide real-time forecasts of the evolution of a nuclear accident situation with sufficient forewarning for the local representative of the Government (the Commissaire de la Republique in the Departement affected) to implement, as required, effective countermeasures to protect the population - for example, confinement indoors or evacuation. Descriptions are given of the principles of this organization and the particular precautions taken to confront the problems of mobilizing experts and of dealing with the saturation of normal telecommunications channels to be expected in the event of a nuclear accident. The organization set up for the installations belonging to Electricite de France is given as a detailed example. Particular stress is placed on the organizational arrangements of the Institute for Radiation Protection and Nuclear Safety designed to provide the emergency teams with the evaluation and forecasting tools they require to carry out their tasks. The procedures are on the whole well developed for atmospheric radioactivity transport, for which operational models already exist. Computer-backed methods with improved performance are at present being developed. A method of forecasting the behaviour of the releases resulting from nuclear accidents is set out for pressurized water reactors, based on evaluating the physical state of the installation, confinement integrity, availability of safety and backup systems, support systems and feed sources and on forecasting how this state will develop on the basis of measured and inferred physical values transmitted from the affected power station through a national network. The experience acquired during accident

  16. Social Sensorimotor Contingencies

    OpenAIRE

    Bütepage, Judith

    2016-01-01

    As the field of robotics advances, more robots are employed in our everyday environment. Thus, the implementation of robots that can actively engage in physical collaboration and naturally interact with humans is of high importance. In order to achieve this goal, it is necessary to study human interaction and social cognition and how these aspects can be implemented in robotic agents. The theory of social sensorimotor contingencies hypothesises that many aspects of human-human interaction de...

  17. Recovery operations in the event of a nuclear accident or radiological emergency

    International Nuclear Information System (INIS)

    1990-01-01

    Much progress has been made over the last decade in the field of emergency planning and preparedness, including the development of guidance, criteria, training programmes, regulations and comprehensive plans in the support of nuclear facilities. To provide a forum for international review and discussion of actual experiences gained and lessons learned from the different aspects of recovery techniques and operations in response to serious accidents at nuclear facilities and accidents associated with radioactive materials, the IAEA organized the International Symposium on Recovery Operations in the Event of a Nuclear Accident or Radiological Emergency. The symposium was held from 6 to 10 November 1989 in Vienna, Austria, and was attended by over 250 experts from 35 Member State and 7 international organizations. Although the prime focus was on on-site and off-site recovery from nuclear reactor accidents and on recovery from radiological accidents unrelated to nuclear power plants, development of emergency planning and preparedness resources was covered as well. From the experiences reported, lessons learned were identified. While further work remains to be done to improve concepts, plans, materials, communications and mechanisms to assemble quickly all the special resources needed in the event of an accident, there was general agreement that worldwide preparations to handle any possible future radiological emergencies had vastly improved. A special feature of the symposium programme was the inclusion of a full session on an accident involving a chemical explosion in a high level waste tank a a plutonium extraction plant in the Southern Urals in the USSR in 1957. Information was presented on the radioactive release, its dissemination and deposition, the resultant radiation situation, dose estimates, health effects follow-up, and the rehabilitation of contaminated land. This volume contains the full text of the 49 papers presented at the symposium together with a

  18. Analysis of the Power oscillations event in Laguna Verde Nuclear Power Plant. Preliminary Report

    International Nuclear Information System (INIS)

    Gonzalez M, V.M.; Amador G, R.; Castillo, R.; Hernandez, J.L.

    1995-01-01

    The event occurred at Unit 1 of Laguna Verde Nuclear Power Plant in January 24, 1995, is analyzed using the Ramona 3 B code. During this event, Unit 1 suffered power oscillation when operating previous to the transfer at high speed recirculating pumps. This phenomenon was timely detected by reactor operator who put the reactor in shut-down doing a manual Scram. Oscillations reached a maximum extent of 10.5% of nominal power from peak to peak with a frequency of 0.5 Hz. Preliminary evaluations show that the event did not endangered the fuel integrity. The results of simulating the reactor core with Ramona 3 B code show that this code is capable to moderate reactor oscillations. Nevertheless it will be necessary to perform a more detailed simulation of the event in order to prove that the code can predict the beginning of oscillations. It will be need an additional analysis which permit the identification of factors that influence the reactor stability in order to express recommendations and in this way avoid the recurrence of this kind of events. (Author)

  19. Development of technique for estimating primary cooling system break diameter in predicting nuclear emergency event sequence

    International Nuclear Information System (INIS)

    Tatebe, Yasumasa; Yoshida, Yoshitaka

    2012-01-01

    If an emergency event occurs in a nuclear power plant, appropriate action is selected and taken in accordance with the plant status, which changes from time to time, in order to prevent escalation and mitigate the event consequences. It is thus important to predict the event sequence and identify the plant behavior resulting from the action taken. In predicting the event sequence during a loss-of-coolant accident (LOCA), it is necessary to estimate break diameter. The conventional method for this estimation is time-consuming, since it involves multiple sensitivity analyses to determine the break diameter that is consistent with the plant behavior. To speed up the process of predicting the nuclear emergency event sequence, a new break diameter estimation technique that is applicable to pressurized water reactors was developed in this study. This technique enables the estimation of break diameter using the plant data sent from the safety parameter display system (SPDS), with focus on the depressurization rate in the reactor cooling system (RCS) during LOCA. The results of LOCA analysis, performed by varying the break diameter using the MAAP4 and RELAP5/MOD3.2 codes, confirmed that the RCS depressurization rate could be expressed by the log linear function of break diameter, except in the case of a small leak, in which RCS depressurization is affected by the coolant charging system and the high-pressure injection system. A correlation equation for break diameter estimation was developed from this function and tested for accuracy. Testing verified that the correlation equation could estimate break diameter accurately within an error of approximately 16%, even if the leak increases gradually, changing the plant status. (author)

  20. Training first responders on Radiological Dispersal Devices (RDDs) and Improvised Nuclear Devices (INDs) events

    International Nuclear Information System (INIS)

    Groves, Ken L.

    2008-01-01

    Full text: This paper will present an overview of the current training the author is presenting to First Responders (fire-fighters, emergency medical technicians, law enforcement and others) who may encounter either a Radiological Dispersal Device (RDD or Dirty Bomb) or an Improvised Nuclear Device (IND) as a part of their Emergency Response activities. The emphasis of the training is putting the radiological/nuclear material in perspective as compared with other Weapons of Mass Destruction (WMD) materials such as chemical and/or biological weapon agents. A goal of the training is to help this First Responder Community understand that under almost all conditions, they can perform their primary mission of 'putting out fires', rescuing and treating injured persons, and chasing 'bad guys' even in the presence of relatively large amount of radiological/nuclear contamination. The rare cases of high activity unshielded sources will be reviewed and explained. Current International guidance on dose 'limits' will be discussed. A discussion of the use of Time, Distance and Shielding as well as appropriate Personal Protective Clothing and how it will provide the needed protection while immediate actions take place early in an RDD/IND event, will take place. The use of appropriate radiation detection instrumentation, documented Standard Operating Procedures along with realistic training, drills and exercises are the key to a successful response to an RDD/IND event for this community of critical emergency responders. (author)

  1. Evaluation of corrective action data for reportable events at commercial nuclear power plants

    International Nuclear Information System (INIS)

    Mays, G.T.

    1991-01-01

    805The Nuclear Regulatory Commission (NRC) approved the adoption of cause codes for reportable events as a new performance indicator (PI) in March 1989. Corrective action data associated with the causes of events were to be compiled also. The corrective action data was considered as supplemental information but not identified formally as a performance indicator. In support of NRC, the Nuclear Operations Analysis Center (NOAC) at the Oak Ridge National Laboratory (ORNL) has been routinely evaluating licensee event reports (LERs) for cause code and corrective action data since 1989. The compilation of corrective action data by NOAC represents the first systematic and comprehensive compilation of this type data. The thrust of analyzing the corrective action data was to identify areas where licensees allocated resources to solve problems and prevent the recurrence of personnel errors and equipment failures. The predominant areas of corrective action reported by licensees are to be evaluated by NRC to compare with NRC programs designed to improve plant performance. The set of corrective action codes used to correlate with individual cause codes and included in the analyses were: training, procedural modification, corrective discipline, management change, design modification, equipment replacement/adjustment, other, and unknown. 1 fig

  2. Events

    Directory of Open Access Journals (Sweden)

    Igor V. Karyakin

    2016-02-01

    Full Text Available The 9th ARRCN Symposium 2015 was held during 21st–25th October 2015 at the Novotel Hotel, Chumphon, Thailand, one of the most favored travel destinations in Asia. The 10th ARRCN Symposium 2017 will be held during October 2017 in the Davao, Philippines. International Symposium on the Montagu's Harrier (Circus pygargus «The Montagu's Harrier in Europe. Status. Threats. Protection», organized by the environmental organization «Landesbund für Vogelschutz in Bayern e.V.» (LBV was held on November 20-22, 2015 in Germany. The location of this event was the city of Wurzburg in Bavaria.

  3. The Effect of the Japan 2011 Disaster on Nuclear and Alternative Energy Stocks Worldwide: An Event Study

    Directory of Open Access Journals (Sweden)

    Robert Ferstl

    2012-05-01

    Full Text Available This event study investigates the impact of the Japanese nuclear disaster in Fukushima-Daiichi on the daily stock prices of French, German, Japanese, and U.S. nuclear utility and alternative energy firms. Hypotheses regarding the (cumulative abnormal returns based on a three-factor model are analyzed through joint tests by multivariate regression models and bootstrapping. Our results show significant abnormal returns for Japanese nuclear utility firms during the one-week event window and the subsequent four-week post-event window. Furthermore, while French and German nuclear utility and alternative energy stocks exhibit significant abnormal returns during the event window, we cannot confirm abnormal returns for U.S. stocks.

  4. Statistical calculation of complete events in medium-energy nuclear collisions

    International Nuclear Information System (INIS)

    Randrup, J.

    1984-01-01

    Several heavy-ion accelerators throughout the world are presently able to deliver beams of heavy nuclei with kinetic energies in the range from tens to hundreds of MeV per nucleon, the so-called medium or intermediate energy range. At such energies a large number of final channels are open, each consisting of many nuclear fragments. The disassembly of the collision system is expected to be a very complicated process and a detailed dynamical description is beyond their present capability. However, by virtue of the complexity of the process, statistical considerations may be useful. A statistical description of the disassembly yields the least biased expectations about the outcome of a collision process and provides a meaningful reference against which more specific dynamical models, as well as the data, can be discussed. This lecture presents the essential tools for formulating a statistical model for the nuclear disassembly process. The authors consider the quick disassembly (explosion) of a hot nuclear system, a so-called source, into multifragment final states, which complete according to their statistical weight. First some useful notation is introduced. Then the expressions for exclusive and inclusive distributions are given and the factorization of an exclusive distribution into inclusive ones is carried out. In turn, the grand canonical approximation for one-fragment inclusive distributions is introduced. Finally, it is outlined how to generate a statistical sample of complete final states. On this basis, a model for statistical simulation of complete events in medium-energy nuclear collisions has been developed

  5. Nuclear event time histories and computed site transfer functions for locations in the Los Angeles region

    Science.gov (United States)

    Rogers, A.M.; Covington, P.A.; Park, R.B.; Borcherdt, R.D.; Perkins, D.M.

    1980-01-01

    This report presents a collection of Nevada Test Site (NTS) nuclear explosion recordings obtained at sites in the greater Los Angeles, Calif., region. The report includes ground velocity time histories, as well as, derived site transfer functions. These data have been collected as part of a study to evaluate the validity of using low-level ground motions to predict the frequency-dependent response of a site during an earthquake. For this study 19 nuclear events were recorded at 98 separate locations. Some of these sites have recorded more than one of the nuclear explosions, and, consequently, there are a total of 159, three-component station records. The location of all the recording sites are shown in figures 1–5, the station coordinates and abbreviations are given in table 1. The station addresses are listed in table 2, and the nuclear explosions that were recorded are listed in table 3. The recording sites were chosen on the basis of three criteria: (1) that the underlying geological conditions were representative of conditions over significant areas of the region, (2) that the site was the location of a strong-motion recording of the 1971 San Fernando earthquake, or (3) that more complete geographical coverage was required in that location.

  6. International exchange of radiological information in the event of a nuclear accident - future perspectives

    International Nuclear Information System (INIS)

    De-Cort, M.; De-Vries, G.; Breitenbach, L.; Leeb, H.; Weiss, W.

    1996-01-01

    Immediately after the Chernobyl accident most European countries established or enhanced their national radioactivity monitoring and information systems. The large transboundary effect of the radioactive release also triggered the need for bilateral and international agreements on the exchange of radiological information in case of a nuclear accident. Based on the experiences gained from existing bi- and multilateral data exchange the Commission of the European Communities has made provision for and is developing technical systems to exchange information of common interest. Firstly the existing national systems and systems based on bilateral agreements are summarized. The objectives and technical realizations of the EC international information exchange systems ECURIE and EURDEP, are described. The experiences gained over the past few years and the concepts for the future, in which central and eastern European countries will be included, are discussed. The benefits that would result from improving the international exchange of radiological information in the event of a future nuclear accident are further being described

  7. The Use of the International Nuclear and Radiological Event Scale (INES) for Event Communication. Guidelines and Good Practices for Setting up a National Framework on the Effective Use of INES for Event Communication

    International Nuclear Information System (INIS)

    2014-10-01

    The IAEA’s International Nuclear and Radiological Event Scale (INES) was developed in 1990 by international experts convened by the IAEA and the OECD Nuclear Energy Agency with the aim of communicating the safety significance of events at nuclear installations. Since then, INES has been expanded to meet the growing need for communicating the safety significance of events giving rise to radiation risk. At present, INES is used for communicating to the public, in a consistent way, the safety significance of an event associated with sources of radiation, whether or not the event occurs at a facility. INES covers a wide spectrum of practices, including industrial uses such as gammagraphy, the use of sources of radiation in medicine, activities at nuclear power plants and research reactors, activities at spent nuclear fuel and radioactive waste management facilities, and the transport of radioactive material. INES has become a widely used tool for putting the safety significance of radiation events into proper perspective. The number of countries using INES has risen steadily over the past five years. As a result, there is a need to ensure the harmonized application of this scale worldwide. Up to now, international activities regarding INES have focused more on developing guidance on rating events than on the ways of using INES. This publication is the first to provide guidance on establishing or improving a national framework for the effective use of INES during event communication. It has been prepared on the basis of national experience with communicating events that have occurred since the introduction of INES. This publication also includes, in Annex I, lessons learned from the application of INES during and after the accident at the Fukushima Daiichi nuclear power plant, Guidance on the Use of INES in Evolving Severe Accidents

  8. Experience feedback of operational events of the control rod assembly and its drive mechanism in nuclear power plants

    International Nuclear Information System (INIS)

    Zhou Hong; Xiao Zhi; Tao Shusheng; Zheng Lixin; Chen Zhaolin

    2013-01-01

    Seventeen operational events of the control rod assembly and its drive mechanism are collected from 1992 to 2012 important nuclear operational events and feedback in referred nuclear power plants. After investigated and classified, several important issues, such as the impact of control rod swell and fuel assembly distortion, control rod drive mechanism leakage, and the control system reliability of control rod, are emphatically analyzed. Some suggestions of experience feedback are proposed. (authors)

  9. Extreme external events in the design and assessment of nuclear power plants

    International Nuclear Information System (INIS)

    2003-03-01

    The analysis of feedback experience from the operation of nuclear power plants (NPPs) in the past 20 years shows few cases of degradation of the plant safety initiated by external events. However, when these have occurred, the consequences have been serious, involving challenges to the defence in depth of the plant. Part of the problem involves the definition of the design basis parameters for some scenarios and differences among regulators on the methods for the protection of operational NPPs in relation to external events. This results in different engineering practices in Member States for the siting and design of NPPs. In the framework of the present revision of the IAEA safety standards on siting and design of NPPs, many initiatives have been implemented by the IAEA in recent years aimed at a systematic analysis of engineering practices in Member States. The most recent event in this connection was a Technical Committee Meeting (TCM) on Structural Safety of NPPs in Relation to Extreme External Loads, organized with the specific objective of evaluating the state of the art of NPP design in relation to external events. Such an analysis provided a technical background for the development of a common technical basis for an integrated approach in site evaluation, design and operation in relation to extreme external events. The scope included new and existing plants, as they are required to meet the same general safety principles, in spite of their peculiarities. The objective of this publication is to provide a technical background to drive regulators, plant owners and designers in the definition of a consistent strategy in selected safety issues on site evaluation, design and operation in relation to extreme external events. This publication is also of support to the IAEA in the development of safety standards since many Safety Guides dealing with related topics are under periodic review. Four major tasks were identified to comply with these general objectives

  10. External main-induced events in relation to nuclear power plant siting

    International Nuclear Information System (INIS)

    1981-01-01

    This safety Guide recomments procedures and provides information for use in implementing that part of the code of safety in Nuclear Power Plant Siting (IAEA Safety Series No. 50-C-S) which concerns man-induced events external to the plant, up to the evaluation of corresponding design basis parameters. Like the code, the Guide forms part of the IAEA's programme, referred to as the NUSS programme, for establishing codes of practice and safety Guides relating to land-based stationary thermal neutron power plants

  11. Calculating Nuclear Power Plant Vulnerability Using Integrated Geometry and Event/Fault-Tree Models

    International Nuclear Information System (INIS)

    Peplow, Douglas E.; Sulfredge, C. David; Sanders, Robert L.; Morris, Robert H.; Hann, Todd A.

    2004-01-01

    Since the events of September 11, 2001, the vulnerability of nuclear power plants to terrorist attacks has become a national concern. The results of vulnerability analysis are greatly influenced by the computational approaches used. Standard approximations used in fault-tree analysis are not applicable for attacks, where high component failure probabilities are expected; two methods that do work with high failure probabilities are presented. Different blast modeling approaches can also affect the end results. Modeling the structural details of facility buildings and the geometric layout of components within the buildings is required to yield meaningful results

  12. Issues and decisions for nuclear power plant management after fuel damage events

    International Nuclear Information System (INIS)

    1997-04-01

    Experience has shown that the on-site activities following an incident that results in severely damaged fuel at a nuclear power plant required extraordinary effort. Even in cases that are not extreme but in which fuel damage is greater than mentioned in the specifications for operation, the recovery will require extensive work. This publication includes information from several projects at the IAEA since 1989 that have resulted in a Technical Report, a TECDOC and a Workshop. While the initial purpose of the projects was focused on providing technical information transfer to the experts engaged in recovery work at the damaged unit of Chernobyl NPP, the results have led to a general approach to managing events in which there is substantial fuel damage. This TECDOC summarizes the work to focus on management issues that may be encountered in any such event whether small or large. 11 refs, 2 figs, 5 tabs

  13. The International Nuclear Event Scale (INES) user's manual. 2001 edition; La escala internacional de sucesos nucleares (INES) manual del usuario. Edicion de 2001

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2001-12-01

    The International Nuclear Event Scale (INES) was introduced in March 1990 jointly by the International Atomic Energy Agency (IAEA) and the Nuclear Energy Agency of the Organisation for Economic Co-operation and Development (OECD/NEA). Its primary purpose is to facilitate communication and understanding between the nuclear community, the media and the public on the safety significance of events occurring at nuclear installations. The scale was refined in 1992 in the light of experience gained and extended to be applicable to any event associated with radioactive material and/or radiation, including the transport of radioactive materials.This edition of the INES User's Manual incorporates experience gained from applying the 1992 version of the scale and the document entitled 'Clarification of Issues Raised'. As such, it replaces those earlier publications. It does not amend the technical basis of the INES rating procedure but is expected to facilitate the task of those who are required to rate the safety significance of events using the INES scale. The INES communication network currently receives and disseminates event information to the INES National Officers of 60 Member States on special Event Rating Forms which represent official information on the events, including the rating. The INES communication process has led each participating country to set up an internal network which ensures that all events are promptly communicated and rated whenever they have to be reported outside or inside the country. The IAEA provides training services on the use of INES on request.

  14. Optically-based Sensor System for Critical Nuclear Facilities Post-Event Seismic Structural Assessment

    Energy Technology Data Exchange (ETDEWEB)

    McCallen, David [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Petrone, Floriana [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Buckle, Ian [Univ. of Nevada, Reno, NV (United States); Wu, Suiwen [Univ. of Nevada, Reno, NV (United States); Coates, Jason [California State Univ., Chico, CA (United States)

    2017-09-30

    The U.S. Department of Energy (DOE) has ownership and operational responsibility for a large enterprise of nuclear facilities that provide essential functions to DOE missions ranging from national security to discovery science and energy research. These facilities support a number of DOE programs and offices including the National Nuclear Security Administration, Office of Science, and Office of Environmental Management. With many unique and “one of a kind” functions, these facilities represent a tremendous national investment, and assuring their safety and integrity is fundamental to the success of a breadth of DOE programs. Many DOE critical facilities are located in regions with significant natural phenomenon hazards including major earthquakes and DOE has been a leader in developing standards for the seismic analysis of nuclear facilities. Attaining and sustaining excellence in nuclear facility design and management must be a core competency of the DOE. An important part of nuclear facility management is the ability to monitor facilities and rapidly assess the response and integrity of the facilities after any major upset event. Experience in the western U.S. has shown that understanding facility integrity after a major earthquake is a significant challenge which, lacking key data, can require extensive effort and significant time. In the work described in the attached report, a transformational approach to earthquake monitoring of facilities is described and demonstrated. An entirely new type of optically-based sensor that can directly and accurately measure the earthquake-induced deformations of a critical facility has been developed and tested. This report summarizes large-scale shake table testing of the sensor concept on a representative steel frame building structure, and provides quantitative data on the accuracy of the sensor measurements.

  15. Social contingencies, the aged, and public policy.

    Science.gov (United States)

    Hudson, R B

    1993-01-01

    Today's older population is notably different than it was a few decades ago, both in well-being and in diversity, a shift that must be acknowledged in public policy. The U.S. social insurance system overprotects against highly likely, predictable, and nonvolatile events at the expense of more unlikely, potentially catastrophic, and less volatile events. The public sector, therefore, should move toward proportionally emphasizing health-related, functionally impairing events rather than income maintenance; the private sector is better suited to insuring against predictable and nonvolatile old-age events. A contingent event scheme would: (a) encourage the growth of long-term-care insurance; (b) help bridge the gap between those arguing for greater "efficiencies" in social welfare spending and those pressing for new universal benefits; and (c) bring a new perspective to the "generational equity" debate.

  16. Development of accident event trees and evaluation of safety system failure modes for the nuclear ultra large crude carrier

    International Nuclear Information System (INIS)

    Lewe, C.K.; Coffey, R.S.; Goodwin, E.F.; Maltese, J.G.; Pyatt, D.W.

    1978-01-01

    A method of applying the probabilistic accident event tree methodology to safety assessments of a nuclear powered Ultra Large Crude Carrier is presented. Also presented are the procedures by which an external accident initiating event, such as a ship collision, may be correlated with the probabilities of damage to the ship's safety systems and to their ultimate availabilities to perform required safety functions

  17. Behaviors and Conditions that Challenge Teamwork: An Assessment of Operating Events at U.S. Commercial Nuclear Power Plants

    International Nuclear Information System (INIS)

    Desaulniers, David R.

    1998-01-01

    As part of its regulatory activities, the U.S. Nuclear Regulatory Commission (NRC) reviews events and routine activities at commercial nuclear power facilities throughout the United States. Frequently, these reviews have highlighted team performance as an important factor in either the initiation or mitigation of significant events and conditions at these facilities. This paper summarizes operating experience relevant to the understanding of teamwork at U.S. nuclear power plants during recent years, describes the specific behaviors that were considered detrimental to team performance, and discusses the conditions that were identified as contributing to these behaviors. (author)

  18. A study for the sequence of events (SOE) system on the nuclear power plant

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Byung Chae; Jeon, Jong Sun; Lee, Sun Sung; Lee, Kyung Ho; Lee, Byung Ju; Sohn, Kwang Young [Korea Atomic Energy Research Institute, Taejon (Korea, Republic of)

    1996-06-01

    It is important to identify where and why an event or a trip is occurred in the Nuclear Power Plant(NPP) and to provide proper resolution against above situation. In order to analyze the prime cause or conspicuous reason of trouble occurred after events or trips occur, the Sequence of Events(SOE) system has been adopted in Korean NPP to acquire the sequential information along where and when an event or a trip take place. The SOE system of UCN 3 and 4 plant which is included in the Plant Data Acquisition System (PDAS), shares the 3205 computer and system software with PDAS. Sharing of the computer H/w and S/W, however, requires more complicated process to provide the events or trip signals due to the inherent characteristics of the shared system. Moreover there are high potentiality of collision between synchronization signals and data transmitted to the Plant Computer System (PCS), when the synchronization signals are sent from PCS to the three SOE processors. When this collision happens the SOE system will break down, thus it is not possible to analyze the trend of events or trips. An independent SOE system composed with single processor is proposed in this paper. To begin with, the analyses on the hardware and software of SOE and PDAS system of UCN 3 and 4 were performed to justify the problems and the resolution if it exists. In order to test the new SOE system, VMEbus, VM30 CPU, change of status I/O card and OS-9 for the operating system were adopted and the analysis for this test system was done as follows; the verification should be achieved through the simulation; the simulated signals for events are given the test system as inputs and the outputs are monitored to verify whether the sequential events logging function works well or not on PC. In conclusion, this report is expected to provide the technical background for the improvement and changing of the NPP PDAS and SOE system in the future. 18 tabs., 33 figs., 26 refs. (Author) .new.

  19. A study for the sequence of events (SOE) system on the nuclear power plant

    International Nuclear Information System (INIS)

    Lee, Byung Chae; Jeon, Jong Sun; Lee, Sun Sung; Lee, Kyung Ho; Lee, Byung Ju; Sohn, Kwang Young

    1996-06-01

    It is important to identify where and why an event or a trip is occurred in the Nuclear Power Plant(NPP) and to provide proper resolution against above situation. In order to analyze the prime cause or conspicuous reason of trouble occurred after events or trips occur, the Sequence of Events(SOE) system has been adopted in Korean NPP to acquire the sequential information along where and when an event or a trip take place. The SOE system of UCN 3 and 4 plant which is included in the Plant Data Acquisition System (PDAS), shares the 3205 computer and system software with PDAS. Sharing of the computer H/w and S/W, however, requires more complicated process to provide the events or trip signals due to the inherent characteristics of the shared system. Moreover there are high potentiality of collision between synchronization signals and data transmitted to the Plant Computer System (PCS), when the synchronization signals are sent from PCS to the three SOE processors. When this collision happens the SOE system will break down, thus it is not possible to analyze the trend of events or trips. An independent SOE system composed with single processor is proposed in this paper. To begin with, the analyses on the hardware and software of SOE and PDAS system of UCN 3 and 4 were performed to justify the problems and the resolution if it exists. In order to test the new SOE system, VMEbus, VM30 CPU, change of status I/O card and OS-9 for the operating system were adopted and the analysis for this test system was done as follows; the verification should be achieved through the simulation; the simulated signals for events are given the test system as inputs and the outputs are monitored to verify whether the sequential events logging function works well or not on PC. In conclusion, this report is expected to provide the technical background for the improvement and changing of the NPP PDAS and SOE system in the future. 18 tabs., 33 figs., 26 refs. (Author) .new

  20. Statistical analysis of events related to emergency diesel generators failures in the nuclear industry

    Energy Technology Data Exchange (ETDEWEB)

    Kančev, Duško, E-mail: dusko.kancev@ec.europa.eu [European Commission, DG-JRC, Institute for Energy and Transport, P.O. Box 2, NL-1755 ZG Petten (Netherlands); Duchac, Alexander; Zerger, Benoit [European Commission, DG-JRC, Institute for Energy and Transport, P.O. Box 2, NL-1755 ZG Petten (Netherlands); Maqua, Michael [Gesellschaft für Anlagen-und-Reaktorsicherheit (GRS) mbH, Schwetnergasse 1, 50667 Köln (Germany); Wattrelos, Didier [Institut de Radioprotection et de Sûreté Nucléaire (IRSN), BP 17 - 92262 Fontenay-aux-Roses Cedex (France)

    2014-07-01

    Highlights: • Analysis of operating experience related to emergency diesel generators events at NPPs. • Four abundant operating experience databases screened. • Delineating important insights and conclusions based on the operating experience. - Abstract: This paper is aimed at studying the operating experience related to emergency diesel generators (EDGs) events at nuclear power plants collected from the past 20 years. Events related to EDGs failures and/or unavailability as well as all the supporting equipment are in the focus of the analysis. The selected operating experience was analyzed in detail in order to identify the type of failures, attributes that contributed to the failure, failure modes potential or real, discuss risk relevance, summarize important lessons learned, and provide recommendations. The study in this particular paper is tightly related to the performing of statistical analysis of the operating experience. For the purpose of this study EDG failure is defined as EDG failure to function on demand (i.e. fail to start, fail to run) or during testing, or an unavailability of an EDG, except of unavailability due to regular maintenance. The Gesellschaft für Anlagen und Reaktorsicherheit mbH (GRS) and Institut de Radioprotection et de Sûreté Nucléaire (IRSN) databases as well as the operating experience contained in the IAEA/NEA International Reporting System for Operating Experience and the U.S. Licensee Event Reports were screened. The screening methodology applied for each of the four different databases is presented. Further on, analysis aimed at delineating the causes, root causes, contributing factors and consequences are performed. A statistical analysis was performed related to the chronology of events, types of failures, the operational circumstances of detection of the failure and the affected components/subsystems. The conclusions and results of the statistical analysis are discussed. The main findings concerning the testing

  1. A retrospective look on plant events for prospective affirmation of nuclear safety

    International Nuclear Information System (INIS)

    Koshy, Thomas; Khamis, Ibrahim

    2014-01-01

    The nuclear industry continues to rise above the challenges resulting from major plant events around the world. It is important to study the significant events, develop solutions to overcome the vulnerabilities identified, and retain the lessons while technology evolves to the next generation. The historical Station-Black-Out needs to be examined further in a new dimension in the light of 'Fukushima type' events where normal AC power recovery in a reasonable period was not practical. The plants would need to incorporate diversity in emergency core cooling to account for a condition that inhibits electrical energy as a source of motive power. An electrical event in Sweden that propagated from an electrical switchyard resulted in two core cooling divisions disabled and consequently exacerbating the plant condition by opening the relief system for reactor coolant system and that significantly increased the probability for core damage. A minor spark in an electronic control system card in a US plant caused inadvertent emergency core cooling and disabled the Control Room Operators' capability to intervene and prevent the primary loop from getting completely filled. A renewed assessment is needed to address the following areas for advancing reactor safety in the new evolving generation of plants to advance safety from the event lessons of the past. - Evaluate the diversity in core cooling systems following loss of all AC power onsite - Confirm independence in Reactor Trip, Depressurization and Core and Containment cooling systems for sensors, power supplies and actuation systems - Evaluate the suitability of logic/control system failure mode resulting from power supply failures in instrument channels and/or divisions (Conduct Failure Mode and Effects Analysis for system, power supplies and components). (authors)

  2. Statistical analysis of events related to emergency diesel generators failures in the nuclear industry

    International Nuclear Information System (INIS)

    Kančev, Duško; Duchac, Alexander; Zerger, Benoit; Maqua, Michael; Wattrelos, Didier

    2014-01-01

    Highlights: • Analysis of operating experience related to emergency diesel generators events at NPPs. • Four abundant operating experience databases screened. • Delineating important insights and conclusions based on the operating experience. - Abstract: This paper is aimed at studying the operating experience related to emergency diesel generators (EDGs) events at nuclear power plants collected from the past 20 years. Events related to EDGs failures and/or unavailability as well as all the supporting equipment are in the focus of the analysis. The selected operating experience was analyzed in detail in order to identify the type of failures, attributes that contributed to the failure, failure modes potential or real, discuss risk relevance, summarize important lessons learned, and provide recommendations. The study in this particular paper is tightly related to the performing of statistical analysis of the operating experience. For the purpose of this study EDG failure is defined as EDG failure to function on demand (i.e. fail to start, fail to run) or during testing, or an unavailability of an EDG, except of unavailability due to regular maintenance. The Gesellschaft für Anlagen und Reaktorsicherheit mbH (GRS) and Institut de Radioprotection et de Sûreté Nucléaire (IRSN) databases as well as the operating experience contained in the IAEA/NEA International Reporting System for Operating Experience and the U.S. Licensee Event Reports were screened. The screening methodology applied for each of the four different databases is presented. Further on, analysis aimed at delineating the causes, root causes, contributing factors and consequences are performed. A statistical analysis was performed related to the chronology of events, types of failures, the operational circumstances of detection of the failure and the affected components/subsystems. The conclusions and results of the statistical analysis are discussed. The main findings concerning the testing

  3. Several nuclear events during apoptosis depend on caspase-3 activation but do not constitute a common pathway.

    Directory of Open Access Journals (Sweden)

    Lisa Trisciuoglio

    Full Text Available A number of nuclear events occur during apoptosis, including DNA laddering, nuclear lamina breakdown, phosphorylation of histones H2B and histone H2AX, and the tight binding to chromatin of HMGB1 and CAD, the nuclease responsible for DNA laddering. We have performed an epistasis analysis to investigate whether these events cluster together in pathways. We find that all depend directly or indirectly on caspase-3 activation. CAD activation, H2AX phosphorylation and DNA laddering cluster together into a pathway, but all other events appear to be independent of each other downstream of caspase-3, and likely evolved subject to different functional pressures.

  4. A code for simulation of human failure events in nuclear power plants: SIMPROC

    International Nuclear Information System (INIS)

    Gil, Jesus; Fernandez, Ivan; Murcia, Santiago; Gomez, Javier; Marrao, Hugo; Queral, Cesar; Exposito, Antonio; Rodriguez, Gabriel; Ibanez, Luisa; Hortal, Javier; Izquierdo, Jose M.; Sanchez, Miguel; Melendez, Enrique

    2011-01-01

    Over the past years, many Nuclear Power Plant organizations have performed Probabilistic Safety Assessments to identify and understand key plant vulnerabilities. As part of enhancing the PSA quality, the Human Reliability Analysis is essential to make a realistic evaluation of safety and about the potential facility's weaknesses. Moreover, it has to be noted that HRA continues to be a large source of uncertainty in the PSAs. Within their current joint collaborative activities, Indizen, Universidad Politecnica de Madrid and Consejo de Seguridad Nuclear have developed the so-called SIMulator of PROCedures (SIMPROC), a tool aiming at simulate events related with human actions and able to interact with a plant simulation model. The tool helps the analyst to quantify the importance of human actions in the final plant state. Among others, the main goal of SIMPROC is to check the Emergency Operating Procedures being used by operating crew in order to lead the plant to a safe shutdown plant state. Currently SIMPROC is coupled with the SCAIS software package, but the tool is flexible enough to be linked to other plant simulation codes. SIMPROC-SCAIS applications are shown in the present article to illustrate the tool performance. The applications were developed in the framework of the Nuclear Energy Agency project on Safety Margin Assessment and Applications (SM2A). First an introductory example was performed to obtain the damage domain boundary of a selected sequence from a SBLOCA. Secondly, the damage domain area of a selected sequence from a loss of Component Cooling Water with a subsequent seal LOCA was calculated. SIMPROC simulates the corresponding human actions in both cases. The results achieved shown how the system can be adapted to a wide range of purposes such as Dynamic Event Tree delineation, Emergency Operating Procedures and damage domain search.

  5. Protection of the Population in the event of a Nuclear accident. A Basis for Intervention

    International Nuclear Information System (INIS)

    1990-01-01

    During the years following the Chernobyl accident in 1986, the NEA actively participated in the international effort towards the improvement and better harmonization of the international and national criteria for the protection of the public in the event of a nuclear accident. A first report on this matter, titled Nuclear Accidents: Intervention Levels for Protection of the Public was published by the NEA in 1989. Subsequently, the NEA Committee on Radiation Protection and Public Health set up a small Task Group to provide additional guidance, and to take into account recent developments in other international organizations. The report outlines the status of relevant international activities in the period following the preparation of the 1989 report, discusses the intervention principles and describes both the proposed accident management system and a general scheme for its application. It is to be noted that the principles and criteria for intervention discussed in this report, although developed with specific reference to reactor accidents, apply equally well to activities and possible accidents at other nuclear facilities. The report briefly describes the transition from an accident management situation back to a normal situation and the related problem of changing criteria for the protection of the public. In addition to the traditional exposure pathways -inhalation from the cloud, external irradiation from the cloud and the ground and ingestion of food - the report acknowledges the existence of special pathways, proposing criteria for protecting workers and the public and some examples of their application

  6. Safety culture in nuclear installations: Bangladesh perspectives and key lessons learned from major events

    International Nuclear Information System (INIS)

    Jalil, A.; Rabbani, G.

    2002-01-01

    Steps necessary to be taken to ensure safety in nuclear installations are suggested. One of the steps suggested is enhancing the safety culture. It is necessary to gain a common understanding of the concept itself, the development stages of safety culture by way of good management practices and leadership for safety culture improvement in the long-term. International topical meetings on safety culture may serve as an important forum for exchange of experiences. From such conventions new initiatives and programmes may crop up which when implemented around the world is very likely to improve safety management and thus boost up the safety culture in nuclear installations. International co-operation and learning are to be prompted to facilitate the sharing of the achievements to face the challenges involved in the management of safety and fixing priorities for future work and identify areas of co-operations. Key lessons learned from some major events have been reported. Present status and future trend of nuclear safety culture in Bangladesh have been dealt with. (author)

  7. Analysis of events significant with regard to safety of Bohunice V-1 nuclear power plant

    International Nuclear Information System (INIS)

    Suchomel, J.; Maron, V.; Kmosena, J.

    1986-01-01

    An analysis was made of operating safety of the V-1 nuclear power plant in Jaslovske Bohunice for the years 1980 - 1983. Of the total number of 676 reported failures only three were events with special safety significance, namely a complete loss of power supply for own consumption from the power grid, a failure of pins on the collectors of steam generators, and a failure of the heads of heat technology inspection channels. The failures were categorized according to the systems used in the USSR and in the USA and compared with data on failures in nuclear power plants in the two countries. The conclusions show that the operation of the V-1 nuclear power plant achieves results which are fully comparable with those recorded in 9 WWER-440 power plants operating in various countries. The average coefficient of availability is 0.72 and ranks the power plant in the fourth place among the said 9 plants. A comparison of the individual power plant units showed that of the total number of 22, the first unit of the V-1 plant ranks fifth with a coefficient of 0.78 and the second unit with a coefficient of 0.69 ranks 15th. (Z.M.)

  8. Practical application of double-contingency protection

    International Nuclear Information System (INIS)

    Kent, N.A.; Sanders, C.F.

    1995-01-01

    The Westinghouse Commercial Fuel Fabrication Facility in Columbia, South Carolina, manufactures fuel assemblies and core components for the commercial nuclear power industry. The ammonium diurinate conversion process converts low-enriched ( 235 U) uranium hexafluoride (UF 6 ) or uranyl nitrate into ceramic-grade uranium dioxide (UO 2 ) powder. The UO 2 powder is then tumble blended in 1700-kg containers to ensure powder homogeneity and obtain necessary enrichments. The double-contingency principle is applied to all systems, processes, and components in which special nuclear material is processed, handled, or stored to ensure that an acceptable nuclear criticality margin of safety is maintained. The Nuclear Criticality Safety (NCS) Program at the Columbia plant is divided into three primary functions: analysis and evaluation, implementation, and compliance. The primary task in analysis and evaluation is to develop comprehensive criticality safety evaluations for all proposed new installations and system modifications. These evaluations involve identifying which of the nine physical process parameters directly affect neutron multiplication and establishing bounding assumptions and criticality safety limits (CSLs). The implementation function primarily consists of translating the open-quotes NCS-speakclose quotes (parameters, k eff , contingencies, barriers, controls, etc.) into operator language (procedural requirements, valve positions, flow rates, pressures, temperatures, etc.) and communicating this information clearly to the manufacturing function through procedures and training. The compliance function deals primarily with conducting criticality safety inspections, audits, and process upset investigations. This paper presents two examples of the challenges associated with the practical implementation of the double-contingency principle to the chemical manufacturing process at the Columbia plant

  9. Mathematical aspects of assessing extreme events for the safety of nuclear plants

    Science.gov (United States)

    Potempski, Slawomir; Borysiewicz, Mieczyslaw

    2015-04-01

    In the paper the review of mathematical methodologies applied for assessing low frequencies of rare natural events like earthquakes, tsunamis, hurricanes or tornadoes, floods (in particular flash floods and surge storms), lightning, solar flares, etc., will be given in the perspective of the safety assessment of nuclear plants. The statistical methods are usually based on the extreme value theory, which deals with the analysis of extreme deviation from the median (or the mean). In this respect application of various mathematical tools can be useful, like: the extreme value theorem of Fisher-Tippett-Gnedenko leading to possible choices of general extreme value distributions, or the Pickands-Balkema-de Haan theorem for tail fitting, or the methods related to large deviation theory. In the paper the most important stochastic distributions relevant for performing rare events statistical analysis will be presented. This concerns, for example, the analysis of the data with the annual extreme values (maxima - "Annual Maxima Series" or minima), or the peak values, exceeding given thresholds at some periods of interest ("Peak Over Threshold"), or the estimation of the size of exceedance. Despite of the fact that there is a lack of sufficient statistical data directly containing rare events, in some cases it is still possible to extract useful information from existing larger data sets. As an example one can consider some data sets available from the web sites for floods, earthquakes or generally natural hazards. Some aspects of such data sets will be also presented taking into account their usefulness for the practical assessment of risk for nuclear power plants coming from extreme weather conditions.

  10. Free-field ground motions for the nonproliferation experiment: Preliminary comparisons with nearby nuclear events

    International Nuclear Information System (INIS)

    Olsen, K.H.; Peratt, A.L.

    1994-01-01

    Since 1987, we have installed fixed arrays of tri-axial accelerometers in the fire-field near the shot horizons for low-yield (≤ 20 kt) nuclear events in the N-tunnel complex beneath Rainier Mesa. For the Nonproliferation Experiment (NPE) we augmented the array to achieve 23 free-field stations. Goals are: (a) to examine robustness and stability of various free-field source function estimates -- e.g., reduced displacement potentials (RDP) and spectra; (b) to compare close-in with regional estimates to test whether detailed close-in free-field and/or surface ground motion data can improve predictability of regional-teleseismic source functions; (c) to provide experimental data for checking two-dimensional numerical simulations. We report preliminary comparisons between experimental free-field data for NPE (1993) and three nearby nuclear events (MISTY ECHO, 1988; MINERAL QUARRY, 1990; HUNTERS TROPHY, 1992). All four working points are within 1 km of each other in the same wet tuff bed, thus reducing concerns about possible large differences in material properties between widely separated shots. Initial comparison of acceleration and velocity seismograms for the four events reveals: (1) There is a large departure from the spherical symmetry commonly assumed in analytic treatments of source theory; both vertical and tangential components are surprisingly large. (2) All shots show similar first-peak particle-velocity amplitude decay rates suggesting significant attenuation even in the supposedly purely elastic region. (3) Sharp (>20 Hz) arrivals are not observed at tunnel level from near-surface pP reflections or spall-closure sources -- but broadened peaks are seen that suggest more diffuse reflected energy from the surface and from the Paleozoic limestone basement below tunnel level

  11. Alternative Forms of Fit in Contingency Theory.

    Science.gov (United States)

    Drazin, Robert; Van de Ven, Andrew H.

    1985-01-01

    This paper examines the selection, interaction, and systems approaches to fit in structural contingency theory. The concepts of fit evaluated may be applied not only to structural contingency theory but to contingency theories in general. (MD)

  12. A Study on the Organizational Components Affecting the Communication-Related Events in Nuclear Power Plant

    International Nuclear Information System (INIS)

    Lee, Seung Min; Jang, In Seok; Seong, Poong Hyun

    2009-01-01

    It is important to communicate clearly and effectively in order to achieve and improve team performance, also in the view point of safety, in nuclear power plant (NPP). Researchers have studied on lots of accidents and incidents related to communication and analyzed the elements affecting communication fail in the side of sender-receiver communication process so that they have found which process was failed to communicate each other. But we cannot disregard on human cognition, level of understanding, and individual or team characteristic on the communication process, so we need to analyze the elements of communication-related events in the side of human and team components that we will find why operators could not avoid failing their communication. In this paper we enumerate key organizational components, collect events related to communication in NPP and count the total number of components affecting communication fail. Finally we perform the pairwise-comparison using those values and understand major factors affecting communication-related events

  13. A Review of the Research on Response to Improvised Nuclear Device Events

    Energy Technology Data Exchange (ETDEWEB)

    Bentz, A; Buddemeier, B; Dombroski, M

    2008-07-01

    Following the events of September 11, a litany of imaginable horribles was trotted out before an anxious and concerned public. To date, government agencies and academics are still grappling with how to best respond to such catastrophes, and as Senator Lieberman's quote says above, now is the time to plan and prepare for such events. One of the nation's worst fears is that terrorists might detonate an improvised nuclear device (IND) in an American city. With 9/11 serving as the catalyst, the government and many NGOs have invested money into research and development of response capabilities throughout the country. Yet, there is still much to learn about how to best respond to an IND event. Understanding the state of knowledge, identifying gaps, and making recommendations for how to fill those gaps, this paper will provide a framework under which past findings can be understood and future research can fit. The risk of an improvised nuclear device (IND) detonation may seem unlikely; and while this is hopefully true, due to its destructive capability, IND events must be prepared for. Many people still live under the Cold War mentality that if a city is attacked with a nuclear weapon, there is little chance of survival. This assumption, while perhaps true in the case of multiple, thermonuclear weapons exchanges, does not hold for the current threat. If a single IND were detonated in the United States, there would be many casualties at the point of impact; however, there would also be many survivors and the initial response by two major groups will mean the difference between life and death for many people. These groups are the first responders and the public. Understanding how these two groups prepare, react and interact will improve response to nuclear terrorism. Figure 1 provides a visualization of the response timeline of an IND event. For the purposes of this assessment, it is assumed that to accurately inform the public, three functions need to be

  14. The missions of the IPSN in the event of a nuclear emergency

    International Nuclear Information System (INIS)

    Dallendre, R.

    2001-01-01

    Due to the potential consequences of an accident in a nuclear facility, a national emergency organization was constituted in France, in order to have the capacity to implement countermeasures necessary to protect the surrounding population from the consequences of radioactive releases. The Institute for Nuclear Safety and Protection (IPSN), the technical support of the French nuclear safety authority, provides the technical support needed in this decision-making process. So, in the event of an accident arising at a nuclear facility, the IPSN would set up an Emergency Response Technical Centre (ERTC) at Fontenay-aux-Roses (Hauts-de-Seine). The IPSN's objectives are: - to diagnose the state of the nuclear facility and to monitor its development, - to prepare prognosis for the evolution of the accident and to give an estimation of the associated consequences according to the situation evolution, - to estimate the risk of radioactive releases and the consequences on man and on the environment, mainly on the basis of weather forecasts and on the prognosis. This diagnosis-prognosis approach is build-up, in case of a PWR, with the information on the state of the installation given by the concerned site via audio-conference system and faxes and by the security panels of the nuclear power plant. To perform its missions, the ERTC, which has to be both safe (a failure must not prevent the management of crisis situation) and secure, uses multiple telecommunication resources to dialogue with partners and also mapping computer systems, data bases and software tools: - the SESAME system, which gives, during an accident of a PWR, a calculation method for the diagnosis-prognosis aforesaid, - the CONRAD system, which calculates the atmospheric dispersal of radioactive substances and consequences in the environment in the early phase of an accident, - the ASTRAL code, which allows to cope with long-lasting situations. In order to be operational, the IPSN experts regularly undergo

  15. Contingent Conspiracies: Art, Philosophy, Science

    DEFF Research Database (Denmark)

    Wilson, Alexander

    2013-01-01

    The question of whether creativity comes from being “open” or “closed” to contingent processes, deeply intersects art-historical discourse on authorship, style, technique and practice: from the Greek notion of the Daimon, through commedia dell'arte’s improvised styles and romanticism’s investment......, Hegel) contain a deeper tension between contingency and necessity, often revealed in correlate discussions of the sublime. But as artists find themselves returning again to a concern or care for contingency (a thread running through Heidegger, Levinas and Derrida) or the question how to conspire...... with contingency (Negarestani), they do so today with a new paradigm of scientific knowledge at their disposal. For science too has increasingly been forced to respond to the notion of contingency. Progressively discovering the ubiquity of non-linear dynamics, deterministic chaos and emergent complexity...

  16. Comparison between Japan and the United States in the frequency of events in equipment and components at nuclear power plants

    International Nuclear Information System (INIS)

    Shimada, Yoshio

    2007-01-01

    The Institute of Nuclear Safety System, Incorporated (INSS) conducted trend analyses until 2005 to compare the frequency of events in certain electrical components and instrumentation components at nuclear power plants between Japan and the United States. The results revealed that events have occurred approximately an order of magnitude less often in Japan than in the United States. This paper compared Japan and the United States in more detail in terms of how often events - events reported under the reporting standards of the Nuclear Information Archive (NUCIA) or the Institute of Nuclear Power Operations (INPO) - occurred in electrical components, instrumentation components and mechanical components at nuclear power plants. The results were as follows: (1) In regard to electrical components and instrumentation components, events have occurred one-eighth less frequently in Japan than in the United States, suggesting that the previous results were correct. (2) Events have occurred more often in mechanical components than electrical components and instrumentation components in both Japan and the United States, and there was a smaller difference in the frequency of events in mechanical components between the two countries. (3) Regarding mechanical components, it was found that events in the pipes for critical systems and equipment, such as reactor coolant systems, emergency core cooling systems, instrument and control systems, ventilating and air-conditioning systems, and turbine equipment, have occurred more often in Japan than in the United States. (4) The above observations suggest that there is little scope for reducing the frequency of events in electrical components and instrumentation components, but that mechanical components such as pipes for main systems like emergency core cooling systems and turbine equipment in the case of PWRs, could be improved by re-examining inspection methods and intervals. (author)

  17. Waste Management Project Contingency Analysis

    International Nuclear Information System (INIS)

    Edward L. Parsons, Jr.

    1999-01-01

    The purpose of this report is to provide the office of Waste Management (WM) with recommended contingency calculation procedures for typical WM projects. Typical projects were defined as conventional construction-type activities that use innovative elements when necessary to meet the project objectives. Projects involve treatment, storage, and disposal of low level, mixed low level, hazardous, transuranic, and high level waste. Cost contingencies are an essential part of Total Cost Management. A contingency is an amount added to a cost estimate to compensate for unexpected expenses resulting from incomplete design, unforeseen and unpredictable conditions, or uncertainties in the project scope (DOE 1994, AACE 1998). Contingency allowances are expressed as percentages of estimated cost and improve cost estimates by accounting for uncertainties. The contingency allowance is large at the beginning of a project because there are more uncertainties, but as a project develops, the allowance shrinks to adjust for costs already incurred. Ideally, the total estimated cost remains the same throughout a project. Project contingency reflects the degree of uncertainty caused by lack of project definition, and process contingency reflects the degree of uncertainty caused by use of new technology. Different cost estimation methods were reviewed and compared with respect to terminology, accuracy, and Cost Guide standards. The Association for the Advancement of Cost Engineering (AACE) methods for cost estimation were selected to represent best industry practice. AACE methodology for contingency analysis can be readily applied to WM Projects, accounts for uncertainties associated with different stages of a project, and considers both project and process contingencies and the stage of technical readiness. As recommended, AACE contingency allowances taper off linearly as a project nears completion

  18. Best practices in the organization, management and conduct of an effective investigation of events at nuclear power plants

    International Nuclear Information System (INIS)

    2008-09-01

    IAEA Safety Standards Series No. SF-1 entitled Fundamental Safety Principles: Safety Fundamentals states the need for operating organizations to establish a programme for the feedback and analysis of operating experience in nuclear power plants. Such a programme ensures that operating experience is analysed, events important to safety are reviewed in depth, lessons learned are disseminated to the staff of the organization and to the relevant national and international organizations, and corrective actions are effectively implemented. This publication has been developed to provide advice and assistance to nuclear installations, and related institutions including contractors and support organizations to strengthen and enhance their own feedback process through the implementation of best practices in organization, management and conduct of an effective investigation of events. Conducting an effective investigation of events is essential in supporting a proactive safety management approach of preventing events from occurring. Event investigation is the heart of the operating experience feedback programme and in an operating organization it is essential to develop and maintain necessary expertise in this area. Experience has shown that it is not sufficient to identify only the direct causes of an event and the event is bound to recur unless all the root causes and casual factors for an event are identified and necessary corrective actions are developed and implemented. The present publication is the outcome of a coordinated effort involving the participation of experts of nuclear organizations in several Member States. It was developed to further elaborate on how to implement the event investigation requirements in the area of feedback of operating experience, as specified in the IAEA Safety Requirements publication NS-R-2 on Safety of Nuclear Power Plants: Operation. This document will also complement the publication IAEA Services Series No. 10 - PROSPER Guidelines

  19. Guide on a national system for collecting, assessing and disseminating information on safety-related events in nuclear power plants

    International Nuclear Information System (INIS)

    1983-02-01

    There is a wide spectrum of safety significance in the events that can occur during nuclear power plant operations. It is important that lessons be learned from safety-related events (hereinafter referred to as unusual events) so as to improve the safety of nuclear power plants. Hence formal procedures should be established for this purpose. The purpose of this document is to provide guidance to Member States for establishing a system (hereinafter referred to as a national system) for collecting, storing, retrieving, assessing and disseminating information on unusual events in nuclear power plants. The guidance given is based on experience gained in the use of existing national and international systems. This guide covers a national system that is part of a programme to improve nuclear power plant safety using experience gained from operating plants both within and outside the country. Implementing the recommendations in this guide would render any national system compatible with other national systems and facilitate the participation in the IAEA System for Reporting Unusual Events with Safety Significance (hereinafter referred to as the IAEA Incident Reporting System, IAEA-IRS) for more widespread dissemination of lessons learned from nuclear power plant operation

  20. Exploratory trend and pattern analysis of 1981 through 1983 Licensee Event Report data. Main report. Volume 1

    International Nuclear Information System (INIS)

    Hester, O.V.; Groh, M.R.; Farmer, F.G.

    1986-10-01

    This report presents an overview of the 1981 through 1983 Sequence Coding and Search System (SCSS) data base that contains nuclear power plant operational data derived from Licensee Event Reports (LERs) submitted to the United States Nuclear Regulatory Commission (USNRC). Both overall event reporting and events related to specific components, subsystems, systems, and personnel are discussed. At all of these levels of information, software is used to generate count data for contingency tables. Contingency table analysis is the main tool for the trend and pattern analysis. The tables focus primarily on faults associated with various components and other items of interest across different plants. The abstracts and other SCSS information on the LERs accounting for unusual counts in the tables were examined to gain insights from the events. Trends and patterns in LER reporting and reporting of events for various component groups were examined through log-linear modeling techniques

  1. International policy on intervention in the event of a nuclear accident

    International Nuclear Information System (INIS)

    Jensen, P.H.; Crick, M.J.; Gonzalez, A.J.

    1996-01-01

    Criteria for taking particular protective actions with the aim of preventing or reducing radiation exposures to the population or to workers in the event of a nuclear accident or radiological emergency can be established on the basis of radiological protection principles for intervention situations. It is of utmost importance that pre-established intervention levels for different protective measures form an integral part of an emergency response plan. Generic optimized intervention levels and their derived operational quantities based on the principles given in this paper are judged to provide protection that would be justified and reasonable optimized for a wide range of accident situations although they can only be used as guidelines. Any specific optimization would lead to intervention levels that might be either higher or lower than those emerging from a generic optimization. (author). 9 refs

  2. International policy on intervention in the event of a nuclear accident

    Energy Technology Data Exchange (ETDEWEB)

    Jensen, P H [Risoe National Lab., Roskilde (Denmark); Crick, M J; Gonzalez, A J [International Atomic Energy Agency, Vienna (Austria)

    1996-08-01

    Criteria for taking particular protective actions with the aim of preventing or reducing radiation exposures to the population or to workers in the event of a nuclear accident or radiological emergency can be established on the basis of radiological protection principles for intervention situations. It is of utmost importance that pre-established intervention levels for different protective measures form an integral part of an emergency response plan. Generic optimized intervention levels and their derived operational quantities based on the principles given in this paper are judged to provide protection that would be justified and reasonable optimized for a wide range of accident situations although they can only be used as guidelines. Any specific optimization would lead to intervention levels that might be either higher or lower than those emerging from a generic optimization. (author). 9 refs.

  3. Safety case for the disposal of spent nuclear fuel at Olkiluoto. Features, events and processes 2012

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2012-12-15

    Features, Events and Processes sits within Posiva Oy's Safety Case 'TURVA-2012' portfolio and has the objective of presenting the main features, events and processes (FEPs) that are considered to be potentially significant for the long-term safety of the planned KBS-3V repository for spent nuclear fuel at Olkiluoto. The primary purpose of this report is to support Performance Assessment, Formulation of Radionuclide Release Scenarios, Assessment of the Radionuclide Release Scenarios for the Repository System and Biosphere Assessment by ensuring that the scenarios are comprehensive and take account of all significant FEPs. The main FEPs potentially affecting the disposal system are described for each relevant subsystem component or barrier (i.e. the spent nuclear fuel, the canister, the buffer and tunnel backfill, the auxiliary components, the geosphere and the surface environment). In addition, a small number of external FEPs that may potentially influence the evolution of the disposal system are described. The conceptual understanding and operation of each FEP is described, together with the main features (variables) of the disposal system that may affect its occurrence or significance. Olkiluoto-specific issues are considered when relevant. The main uncertainties (conceptual and parameter/data) associated with each FEP that may affect understanding are also documented. Indicative parameter values are provided, in some cases, to illustrate the magnitude or rate of a process, but it is not the intention of this report to provide the complete set of numerical values that are used in the quantitative safety assessment calculations. Many of the FEPs are interdependent and, therefore, the descriptions also identify the most important direct couplings between the FEPs. This information is used in the formulation of scenarios to ensure the conceptual models and calculational cases are both comprehensive and representative. (orig.)

  4. Safety case for the disposal of spent nuclear fuel at Olkiluoto. Features, events and processes 2012

    International Nuclear Information System (INIS)

    2012-12-01

    Features, Events and Processes sits within Posiva Oy's Safety Case 'TURVA-2012' portfolio and has the objective of presenting the main features, events and processes (FEPs) that are considered to be potentially significant for the long-term safety of the planned KBS-3V repository for spent nuclear fuel at Olkiluoto. The primary purpose of this report is to support Performance Assessment, Formulation of Radionuclide Release Scenarios, Assessment of the Radionuclide Release Scenarios for the Repository System and Biosphere Assessment by ensuring that the scenarios are comprehensive and take account of all significant FEPs. The main FEPs potentially affecting the disposal system are described for each relevant subsystem component or barrier (i.e. the spent nuclear fuel, the canister, the buffer and tunnel backfill, the auxiliary components, the geosphere and the surface environment). In addition, a small number of external FEPs that may potentially influence the evolution of the disposal system are described. The conceptual understanding and operation of each FEP is described, together with the main features (variables) of the disposal system that may affect its occurrence or significance. Olkiluoto-specific issues are considered when relevant. The main uncertainties (conceptual and parameter/data) associated with each FEP that may affect understanding are also documented. Indicative parameter values are provided, in some cases, to illustrate the magnitude or rate of a process, but it is not the intention of this report to provide the complete set of numerical values that are used in the quantitative safety assessment calculations. Many of the FEPs are interdependent and, therefore, the descriptions also identify the most important direct couplings between the FEPs. This information is used in the formulation of scenarios to ensure the conceptual models and calculational cases are both comprehensive and representative. (orig.)

  5. Safety case for the disposal of spent nuclear fuel at Olkiluoto. Features, events and processes 2012

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2012-12-15

    Features, Events and Processes sits within Posiva Oy's Safety Case 'TURVA-2012' portfolio and has the objective of presenting the main features, events and processes (FEPs) that are considered to be potentially significant for the long-term safety of the planned KBS-3V repository for spent nuclear fuel at Olkiluoto. The primary purpose of this report is to support Performance Assessment, Formulation of Radionuclide Release Scenarios, Assessment of the Radionuclide Release Scenarios for the Repository System and Biosphere Assessment by ensuring that the scenarios are comprehensive and take account of all significant FEPs. The main FEPs potentially affecting the disposal system are described for each relevant subsystem component or barrier (i.e. the spent nuclear fuel, the canister, the buffer and tunnel backfill, the auxiliary components, the geosphere and the surface environment). In addition, a small number of external FEPs that may potentially influence the evolution of the disposal system are described. The conceptual understanding and operation of each FEP is described, together with the main features (variables) of the disposal system that may affect its occurrence or significance. Olkiluoto-specific issues are considered when relevant. The main uncertainties (conceptual and parameter/data) associated with each FEP that may affect understanding are also documented. Indicative parameter values are provided, in some cases, to illustrate the magnitude or rate of a process, but it is not the intention of this report to provide the complete set of numerical values that are used in the quantitative safety assessment calculations. Many of the FEPs are interdependent and, therefore, the descriptions also identify the most important direct couplings between the FEPs. This information is used in the formulation of scenarios to ensure the conceptual models and calculational cases are both comprehensive and representative. (orig.)

  6. A concerted action towards improved international response to nuclear and radiological events

    International Nuclear Information System (INIS)

    Ugletveit, F.

    2006-01-01

    After the Chernobyl accident in 1986, two conventions, the Convention on Early Notification of a Nuclear Accident and the Convention on Assistance in the Case of a Nuclear Accident or Radiological Emergency, were established in order to provide a framework for enhanced international cooperation in the response to such events. It has however been widely recognised that a better practical implementation of these conventions could significantly enhance our response capabilities. In order to achieve this the IAEA Member States, their Competent Authorities and the IAEA Secretariat have developed an International Action Plan for Strengthening the International Preparedness and Response System for Nuclear and Radiological Emergencies, 2004-2009. This Action Plan has three main elements: International communication International assistance Sustainable infrastructure and Working Groups and Expert Groups have been established to carry out the work in accordance with the plan. The implementation of the Action Plan is managed jointly by the IAEA Secretariat and the National Competent Authority Coordinating Group, N.C.A.C.G.. Currently some 65 experts from about 30 different states and international organisations are taking part. Two of the main goals of this work are to develop standardised/harmonized response procedures necessary for efficient provision of international assistance and establishment of a common unified communication platform. A more detailed update on the development of the work will be given. The development and implementation of this Action Plan is an important milestone in nuclear and radiological emergency preparedness and response and will offer an opportunity for the international society to establish a better and more cost efficient response capability. The standardised procedures and the unified communication platform established will subsequently have to be adopted and implemented by states and international organisations. This may have significant

  7. Recent advances in medical device triage technologies for chemical, biological, radiological, and nuclear events.

    Science.gov (United States)

    Lansdowne, Krystal; Scully, Christopher G; Galeotti, Loriano; Schwartz, Suzanne; Marcozzi, David; Strauss, David G

    2015-06-01

    In 2010, the US Food and Drug Administration (Silver Spring, Maryland USA) created the Medical Countermeasures Initiative with the mission of development and promoting medical countermeasures that would be needed to protect the nation from identified, high-priority chemical, biological, radiological, or nuclear (CBRN) threats and emerging infectious diseases. The aim of this review was to promote regulatory science research of medical devices and to analyze how the devices can be employed in different CBRN scenarios. Triage in CBRN scenarios presents unique challenges for first responders because the effects of CBRN agents and the clinical presentations of casualties at each triage stage can vary. The uniqueness of a CBRN event can render standard patient monitoring medical device and conventional triage algorithms ineffective. Despite the challenges, there have been recent advances in CBRN triage technology that include: novel technologies; mobile medical applications ("medical apps") for CBRN disasters; electronic triage tags, such as eTriage; diagnostic field devices, such as the Joint Biological Agent Identification System; and decision support systems, such as the Chemical Hazards Emergency Medical Management Intelligent Syndromes Tool (CHEMM-IST). Further research and medical device validation can help to advance prehospital triage technology for CBRN events.

  8. Development of a 3-D Nuclear Event Visualization Program Using Unity

    Science.gov (United States)

    Kuhn, Victoria

    2017-09-01

    Simulations have become increasingly important for science and there is an increasing emphasis on the visualization of simulations within a Virtual Reality (VR) environment. Our group is exploring this capability as a visualization tool not just for those curious about science, but also for educational purposes for K-12 students. Using data collected in 3-D by a Time Projection Chamber (TPC), we are able to visualize nuclear and cosmic events. The Unity game engine was used to recreate the TPC to visualize these events and construct a VR application. The methods used to create these simulations will be presented along with an example of a simulation. I will also present on the development and testing of this program, which I carried out this past summer at MSU as part of an REU program. We used data from the S πRIT TPC, but the software can be applied to other 3-D detectors. This work is supported by the U.S. Department of Energy under Grant Nos. DE-SC0014530, DE-NA0002923 and US NSF under Grant No. PHY-1565546.

  9. Inductive Double-Contingency Analysis of UO2 Powder Bulk Blending Operations at a Commercial Fuel Plant (U)

    International Nuclear Information System (INIS)

    Skiles, S. K.

    1994-01-01

    An inductive double-contingency analysis (DCA) method developed by the criticality safety function at the Savannah River Site, was applied in Criticality Safety Evaluations (CSEs) of five major plant process systems at the Westinghouse Electric Corporation's Commercial Nuclear Fuel Manufacturing Plant in Columbia, South Carolina (WEC-Cola.). The method emphasizes a thorough evaluation of the controls intended to provide barriers against criticality for postulated initiating events, and has been demonstrated effective at identifying common mode failure potential and interdependence among multiple controls. A description of the method and an example of its application is provided

  10. Mini-Membrane Evaporator for Contingency Spacesuit Cooling

    Science.gov (United States)

    Makinen, Janice V.; Bue, Grant C.; Campbell, Colin; Petty, Brian; Craft, Jesse; Lynch, William; Wilkes, Robert; Vogel, Matthew

    2015-01-01

    The next-generation Advanced Extravehicular Mobility Unit (AEMU) Portable Life Support System (PLSS) is integrating a number of new technologies to improve reliability and functionality. One of these improvements is the development of the Auxiliary Cooling Loop (ACL) for contingency crewmember cooling. The ACL is a completely redundant, independent cooling system that consists of a small evaporative cooler--the Mini Membrane Evaporator (Mini-ME), independent pump, independent feedwater assembly and independent Liquid Cooling Garment (LCG). The Mini-ME utilizes the same hollow fiber technology featured in the full-sized AEMU PLSS cooling device, the Spacesuit Water Membrane Evaporator (SWME), but Mini-ME occupies only approximately 25% of the volume of SWME, thereby providing only the necessary crewmember cooling in a contingency situation. The ACL provides a number of benefits when compared with the current EMU PLSS contingency cooling technology, which relies upon a Secondary Oxygen Vessel; contingency crewmember cooling can be provided for a longer period of time, more contingency situations can be accounted for, no reliance on a Secondary Oxygen Vessel (SOV) for contingency cooling--thereby allowing a reduction in SOV size and pressure, and the ACL can be recharged-allowing the AEMU PLSS to be reused, even after a contingency event. The first iteration of Mini-ME was developed and tested in-house. Mini-ME is currently packaged in AEMU PLSS 2.0, where it is being tested in environments and situations that are representative of potential future Extravehicular Activities (EVA's). The second iteration of Mini-ME, known as Mini-ME2, is currently being developed to offer more heat rejection capability. The development of this contingency evaporative cooling system will contribute to a more robust and comprehensive AEMU PLSS.

  11. Advanced Mechanistic 3D Spatial Modeling and Analysis Methods to Accurately Represent Nuclear Facility External Event Scenarios

    Energy Technology Data Exchange (ETDEWEB)

    Sezen, Halil [The Ohio State Univ., Columbus, OH (United States). Dept. of Civil, Environmental and Geodetic Engineering; Aldemir, Tunc [The Ohio State Univ., Columbus, OH (United States). College of Engineering, Nuclear Engineering Program, Dept. of Mechanical and Aerospace Engineering; Denning, R. [The Ohio State Univ., Columbus, OH (United States); Vaidya, N. [Rizzo Associates, Pittsburgh, PA (United States)

    2017-12-29

    Probabilistic risk assessment of nuclear power plants initially focused on events initiated by internal faults at the plant, rather than external hazards including earthquakes and flooding. Although the importance of external hazards risk analysis is now well recognized, the methods for analyzing low probability external hazards rely heavily on subjective judgment of specialists, often resulting in substantial conservatism. This research developed a framework to integrate the risk of seismic and flooding events using realistic structural models and simulation of response of nuclear structures. The results of four application case studies are presented.

  12. 49 CFR 1544.301 - Contingency plan.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 9 2010-10-01 2010-10-01 false Contingency plan. 1544.301 Section 1544.301... COMMERCIAL OPERATORS Threat and Threat Response § 1544.301 Contingency plan. Each aircraft operator must adopt a contingency plan and must: (a) Implement its contingency plan when directed by TSA. (b) Ensure...

  13. 30 CFR 282.26 - Contingency Plan.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 2 2010-07-01 2010-07-01 false Contingency Plan. 282.26 Section 282.26 Mineral... § 282.26 Contingency Plan. (a) When required by the Director, a lessee shall include a Contingency Plan as part of its request for approval of a Delineation, Testing, or Mining Plan. The Contingency Plan...

  14. National Contingency Plan Subpart J

    Science.gov (United States)

    Subpart J of the National Oil and Hazardous Substances Pollution Contingency Plan (NCP) directs EPA to prepare a schedule of dispersants, other chemicals, and oil spill mitigating devices and substances that may be used to remove or control oil discharges.

  15. Precursor analyses - The use of deterministic and PSA based methods in the event investigation process at nuclear power plants

    International Nuclear Information System (INIS)

    2004-09-01

    The efficient feedback of operating experience (OE) is a valuable source of information for improving the safety and reliability of nuclear power plants (NPPs). It is therefore essential to collect information on abnormal events from both internal and external sources. Internal operating experience is analysed to obtain a complete understanding of an event and of its safety implications. Corrective or improvement measures may then be developed, prioritized and implemented in the plant if considered appropriate. Information from external events may also be analysed in order to learn lessons from others' experience and prevent similar occurrences at our own plant. The traditional ways of investigating operational events have been predominantly qualitative. In recent years, a PSA-based method called probabilistic precursor event analysis has been developed, used and applied on a significant scale in many places for a number of plants. The method enables a quantitative estimation of the safety significance of operational events to be incorporated. The purpose of this report is to outline a synergistic process that makes more effective use of operating experience event information by combining the insights and knowledge gained from both approaches, traditional deterministic event investigation and PSA-based event analysis. The PSA-based view on operational events and PSA-based event analysis can support the process of operational event analysis at the following stages of the operational event investigation: (1) Initial screening stage. (It introduces an element of quantitative analysis into the selection process. Quantitative analysis of the safety significance of nuclear plant events can be a very useful measure when it comes to selecting internal and external operating experience information for its relevance.) (2) In-depth analysis. (PSA based event evaluation provides a quantitative measure for judging the significance of operational events, contributors to

  16. Mobile contingency unit

    Energy Technology Data Exchange (ETDEWEB)

    Silva, Sergio O. da; Magalhaes, Milton P. de [Petroleo Brasileiro S.A. (PETROBRAS), Rio de Janeiro, RJ (Brazil); Junqueira, Rodrigo A.; Torres, Carlos A.R. [PETROBRAS Transporte S/A (TRANSPETRO), Rio de Janeiro, RJ (Brazil)

    2009-07-01

    This paper is aimed at presenting what is already a reality in TRANSPETRO in the area covered by OSBRA, a pipeline that carries by-products to the Mid-West region of Brazil. In order to meet the needs of covering occasional accidents, TRANSPETRO counts on a standardized system of emergency management. It is a great challenge to secure an efficient communication along the 964 km of extension, considering that there are shadow zones where it is not possible to use conventional means of communication such as mobile telephony and internet. It was in this context that the Mobile Contingency Unit Via Satellite - MCU was developed, to extend the communication facilities existing in fixed installations to remote places, mainly the pipeline right of ways. In case of emergency, simulation and work in the pipeline right of way, MCU is fully able to provide the same data, voice, closed-circuit TV and satellite video conference facilities that are available in any internal area of the PETROBRAS system. (author)

  17. External human induced events in site evaluation for nuclear power plants. Safety guide

    International Nuclear Information System (INIS)

    2004-01-01

    The purpose of the present Safety Guide is to provide recommendations and guidance for the examination of the region considered for site evaluation for a plant in order to identity hazardous phenomena associated with human induced events initiated by sources external to the plant. In some cases it also presents preliminary guidance for deriving values of relevant parameters for the design basis. This Safety Guide is also applicable for periodic site evaluation and site evaluation following a major human induced event, and for the design and operation of the site's environmental monitoring system. Site evaluation includes site characterization. Consideration of external events that could lead to a degradation of the safety features of the plant and cause a release of radioactive material from the plant and/or affect the dispersion of such material in the environment. And consideration of population issues and access issues significant to safety (such as the feasibility of evacuation, the population distribution and the location of resources). The process of site evaluation continues throughout the lifetime of the facility, from siting to design, construction, operation and decommissioning. The external human induced events considered in this Safety Guide are all of accidental origin. Considerations relating to the physical protection of the plant against wilful actions by third parties are outside its scope. However, the methods described herein may also have some application for the purposes of such physical protection. The present Safety Guide may also be used for events that may originate within the boundaries of the site, but from sources which are not directly involved in the operational states of the nuclear power plant units, such as fuel depots or areas for the storage of hazardous materials for the construction of other facilities at the same site. Special consideration should be given to the hazardous material handled during the construction, operation and

  18. Nuclear and energies Nr 59/June 2012 - Synthesis of significant events from December 2011 until May 2012

    International Nuclear Information System (INIS)

    Lenail, Bernard; Ducroux, Guy; Lamorlette, Guy; Seyve, Claude; Fromant, Bernard; Gollion, Jacques; Miquel, Pierre; Raisonnier, Daniele; Lepine, Gerard; Vandevoir, Roger

    2012-01-01

    A first article comments the fact that, fifteen months after the Fukushima accident, two reactors are about to start again. In two articles dealing with energy, a first one comments the recent evolution of the energy sector (oil market, gas market, European energy) and a second one addresses current events in the sector of renewable energies: in the solar sector (the Photowatt affair, the Myrte and STARS projects), in the offshore wind sector (bidding in France and in Great-Britain). Dealing with the nuclear sector, a first article deals with the uranium market (from mine to fuel) and with AREVA activities in different countries. A second article proposes an overview of world perspectives for nuclear reactors, of nuclear activity in France (energy policy, nuclear safety, the issue of the Fessenheim power station, the EPR in Flamanville, the ATMEA project) and in various countries in Europe (Finland, Great Britain, Germany, Lithuania, Netherlands, Russia, Belarus, Czech Republic, Poland, Switzerland, Spain, Romania), in the United States, China, South Korea, Japan, India, Armenia, Vietnam, Jordan, and South Africa. The last articles address the relationship between nuclear and society (during the presidential campaign in France, in different reports, in the summit on nuclear safety, in Germany where phasing out nuclear raises problems), the impact of nuclear on the environment (situation in France, incidents in different French nuclear installations, and briefly in other countries like Germany, Great-Britain, Spain, Eastern Europe, Ukraine, Iran, China, Japan, Taiwan, USA), and the development of Pb-212-based radio-immunotherapy by Areva Med

  19. SiC detectors to monitor ionizing radiations emitted from nuclear events and plasmas

    Science.gov (United States)

    Torrisi, L.; Cannavò, A.

    2016-09-01

    Silicon Carbide (SiC) semiconductor detectors are increasingly employed in Nuclear Physics for their advantages with respect to traditional silicon (Si). Such detectors show an energy resolution, charge mobility, response velocity and detection efficiency similar to Si detectors. However, the higher band gap (3.26 eV), the lower leakage current (∼10 pA) maintained also at room temperature, the higher radiation hardness and the higher density with respect to Si represent some indisputable advantages characterizing such detectors. The devices can be employed at high temperatures, at high absorbed doses and in the case of high visible light intensities, for example, in plasma, for limited exposition times without damage. Generally SiC Schottky diodes are employed in reverse polarization with an active region depth of the order of 100 µm, purity below 1014 cm-3 and an active area lower than 1 cm2. Measurements in the regime of proportionality with the radiation energy released in the active region and measurements in time-of-flight configuration are employed for nuclear emission events produced at both low and high fluences. Alpha spectra demonstrated an energy resolution of about 1.3% at 5.8 MeV. Radiation emission from laser-generated plasma can be monitored in terms of detected photons, electrons and ions, using the laser pulse as a start signal and the radiation detection as a stop signal, enabling to measure the ion velocity by knowing the target-detector flight distance. SiC spectra acquired in the Messina University laboratories using radioactive ion sources and at the PALS laboratory facility in Prague (Czech Republic) are presented. A preliminary study of the use of SiC detectors, embedded in a water equivalent polymer, as a dosimeter is presented and discussed.

  20. Rethinking Reinforcement: Allocation, Induction, and Contingency

    Science.gov (United States)

    Baum, William M

    2012-01-01

    The concept of reinforcement is at least incomplete and almost certainly incorrect. An alternative way of organizing our understanding of behavior may be built around three concepts: allocation, induction, and correlation. Allocation is the measure of behavior and captures the centrality of choice: All behavior entails choice and consists of choice. Allocation changes as a result of induction and correlation. The term induction covers phenomena such as adjunctive, interim, and terminal behavior—behavior induced in a situation by occurrence of food or another Phylogenetically Important Event (PIE) in that situation. Induction resembles stimulus control in that no one-to-one relation exists between induced behavior and the inducing event. If one allowed that some stimulus control were the result of phylogeny, then induction and stimulus control would be identical, and a PIE would resemble a discriminative stimulus. Much evidence supports the idea that a PIE induces all PIE-related activities. Research also supports the idea that stimuli correlated with PIEs become PIE-related conditional inducers. Contingencies create correlations between “operant” activity (e.g., lever pressing) and PIEs (e.g., food). Once an activity has become PIE-related, the PIE induces it along with other PIE-related activities. Contingencies also constrain possible performances. These constraints specify feedback functions, which explain phenomena such as the higher response rates on ratio schedules in comparison with interval schedules. Allocations that include a lot of operant activity are “selected” only in the sense that they generate more frequent occurrence of the PIE within the constraints of the situation; contingency and induction do the “selecting.” PMID:22287807

  1. New treatment of low probability events with particular application to nuclear power plant incidents

    Energy Technology Data Exchange (ETDEWEB)

    Critchley, O.H.

    1986-01-01

    The 'New Treatment' attempts to resolve the 'Zero-Infinity Dilemmas' posed by the threat of low probability events (LPE) philosophical approach which rejects mathematical idealism in favour of the engineering pragmatism that is characteristic of the scientific method. The LPE is seen as a rare singularity in the stream of 'Event-noise' of mundane, untoward incidents that afflict industrial systems. Engineering inspection which has evolved as a regulatory mechanism can be effective in reducing this 'noise' and the competent inspector is able to recognise the 'loss of resistance to failure' which so often comes before an LPE. Despite that an intractable residual risk remains, but this can be made societally tolerable if there is a justifiable conviction that safety is defended by trustworthy engineering. In an age marked by an increasing complexity and sophistication in its science and technology, the engineer is emerging as the proper central decision maker in such matters standing, athwart pure administration and theory on the one hand and expertise and practice on the other. Moreover, evidence that his intellect may be peculiarly adapted for such a role is coming from recent findings in neuropsychology. The Nuclear Installations Inspectorate is cited as an exemplar of the engineering inspection needed to apprehend those human fallibilities in design and application to which most catastrophic failures of technology are due. However, such regulatory systems and the assessment functions associated with them lack accountability and, as an interpretation of Goedel's theorem suggests, cannot assess their own efficiency. Independent, disinterested appraisal assisted by Signal Detection Theory is offered as a remedy.

  2. Surface motion induced by nuclear explosions beneath Pahute Mesa. Part I. Halfbreak, Greeley, Scotch, Boxcar events

    International Nuclear Information System (INIS)

    Perret, W.R.

    1976-10-01

    Results of surface motion studies conducted by Sandia Laboratories during seven underground nuclear explosions detonated beneath Pahute Mesa, Areas 19 and 20 of the Nevada Test Site, between 1966 and 1973 are reported. The report is divided into two parts of which this, Part I, includes (1) descriptions of the Pahute Mesa geological environment and of the purposes and instrumentation used in these programs (Chapter 1), and (2) description of four events, the data derived from each, and analysis of these data. These Part I events are HALFBEAK (Chapter 2), GREELEY (Chapter 3), SCOTCH (Chapter 4), and BOXCAR (Chapter 5) for all of which a nominally radial array of gage stations yielded data as a function of distance primarily, although in a few cases data were derived from stations at widely separated azimuths from the explosion. Results of the analysis indicate that average propagation velocity through the geologic column between the explosions and mesa surface was about 8800 ft/sec and that for horizontal distances greater than shot depth, refraction occurred within rhyolite flows with characteristic velocity of about 12,300 ft/sec. There is evidence which suggests possible deeper refraction at a velocity between 18,000 and 21,000 ft/sec. Only the verticle motion peaks follow a pattern amenable to regression analysis because geometrical effects influence horizontal motion amplitudes differently as horizontal distances increase. Particle velocities vary roughly as the inverse square of slant or radial range with exponent values ranging from -3.9 to -1.3. Displacements follow a similar pattern with exponents ranging from about -6 to -2. Displacement profiles at various times during the motion and displacement hodographs in the vertical-radial plane aid in understanding several local phenomena implied by individual motion records

  3. Environmental impacts of radiological consequences during the anticipated transients without scram (ATWS) events in nuclear power reactors

    International Nuclear Information System (INIS)

    El-Kafas, A.A.

    2011-01-01

    Anticipated transients without scram (ATWS), is one of the (worst case) accidents could happen if the system that provides a highly reliable means of shutting down the reactor (scram system )fails to work during a reactor event (anticipated transient).It has two general characteristics: (1) Initiation by a transient anticipated to occur one or more times in the life of reactor and ,(2) Assumed to proceed without scram.The types of events considered are those used for designing the plant .The evaluation of the radiological consequences during the assessment of the nuclear events,especially ATWS in nuclear power reactors, is very essential for environmental studies and public safety. In this paper, the root cases for nuclear events and dose calculation are presented. Scenario of accident sequences together with radiological impacts is illustrated for loss of coolant accident (LOCA) for a typical pressurized water reactor nuclear power plant. Recommendations for mitigating or preventing the release of radiation and high radioactive materials to environment are presented.

  4. A study on the determination of threshold values for the initiating event performance indicators of domestic nuclear power plants

    International Nuclear Information System (INIS)

    Kang, D. I.; Park, J. H.; Kim, K. Y.; Whang, M. J.; Yang, J. E.; Sung, G. Y.

    2003-01-01

    In this paper, we determine the threshold values of unplanned reactor scram, domestic initiating event performance indicator, using data of domestic unplanned reactor scram and probabilistic safety assessment model of Korea Standard Nuclear Power Plant(KSNP). We also perform a pilot study of initiating event Risk Based Performance Indicator(RBPI) for KSNP. Study results for unplanned reactor scram show that the threshold value of between green and blue color is 3, that of between blue and yellow color is 6, and that of between yellow and orange color is 30. Pilot study results of initiating event RBPI show that loss of feedwater, transient, and loss of component cooling water events are selected as initiating event RBPI for KSNP

  5. Discrete dynamic event tree modeling and analysis of nuclear power plant crews for safety assessment

    International Nuclear Information System (INIS)

    Mercurio, D.

    2011-01-01

    Current Probabilistic Risk Assessment (PRA) and Human Reliability Analysis (HRA) methodologies model the evolution of accident sequences in Nuclear Power Plants (NPPs) mainly based on Logic Trees. The evolution of these sequences is a result of the interactions between the crew and plant; in current PRA methodologies, simplified models of these complex interactions are used. In this study, the Accident Dynamic Simulator (ADS), a modeling framework based on the Discrete Dynamic Event Tree (DDET), has been used for the simulation of crew-plant interactions during potential accident scenarios in NPPs. In addition, an operator/crew model has been developed to treat the response of the crew to the plant. The 'crew model' is made up of three operators whose behavior is guided by a set of rules-of-behavior (which represents the knowledge and training of the operators) coupled with written and mental procedures. In addition, an approach for addressing the crew timing variability in DDETs has been developed and implemented based on a set of HRA data from a simulator study. Finally, grouping techniques were developed and applied to the analysis of the scenarios generated by the crew-plant simulation. These techniques support the post-simulation analysis by grouping similar accident sequences, identifying the key contributing events, and quantifying the conditional probability of the groups. These techniques are used to characterize the context of the crew actions in order to obtain insights for HRA. The model has been applied for the analysis of a Small Loss Of Coolant Accident (SLOCA) event for a Pressurized Water Reactor (PWR). The simulation results support an improved characterization of the performance conditions or context of operator actions, which can be used in an HRA, in the analysis of the reliability of the actions. By providing information on the evolution of system indications, dynamic of cues, crew timing in performing procedure steps, situation

  6. Safety of Basic nuclear facilities (INB) other than electronuclear reactors. Lessons learned from declared significant events in 2011 and 2012

    International Nuclear Information System (INIS)

    2013-01-01

    The first part of this report presents the different types of basic nuclear facilities other than electronuclear reactors. These installations can be industrial installations dedicated or not to the nuclear fuel cycle, research and support installations, be definitively stopped or being dismantled, or radioactive waste storage installations. After a comment of the main trends noticed in 2011 and 2012, the report proposes a transverse analysis of events which occurred in these installations. These events are related to various risks: dissemination of radioactive materials, exposure to ionizing radiations, criticality, fire and explosion, handling operations, loss of electric supplies or fluids, external aggression. Other events are those significant for the environment with a radiological component, or related to periodic controls and tests. The causes of these events are analysed. Specific events are presented which occurred on different sites (in the MELOX plant, in Areva sites in La Hague, Pierrelatte, in CEA sites in Cadarache and Saclay, in a fuel factory in Romans). Other topics are finally addressed: safety measures after the Fukushima accident, safety and radiation protection management systems of Areva and CEA, dismantling of nuclear installations

  7. Extreme meteorological events in nuclear power plant siting, excluding tropical cyclones

    International Nuclear Information System (INIS)

    1981-01-01

    This Safety Guide deals with the extremes of meteorological variables and the extreme meteorological phenomena in accordance with the general criteria of the Code. The Guide outlines a procedure based on the following steps: (1) The meteorological phenomena and variables are described and classified, according to their effects on safety. (2) Data sources are identified, and data are collected. (3) Meteorological variables such as air temperature are analysed to determine their design bases; and the design basis event in case of phenomena such as the design basis tornado is identified. (4) As appropriate, the design basis value for the variable, or the design basis for the phenomena (such as pressure drop and maximum wind speed of the design basis tornado), is defined. In the following sections, the general procedure for evaluating the design bases of extreme meteorological variables and phenomena is outlined. The procedure is then presented in detail for each variable or phenomenon considered. The variables characterizing the meteorological environment dealt with in this Guide are wind speed, atmospheric precipitation, and temperature. The extreme meteorological phenomena discussed here are the tornado and, briefly, the tropical cyclone, which is discussed more extensively in the Safety Guide on Design Basis Tropical Cyclone for Nuclear Power Plants (IAEA Safety Series No. 50-SG-S11B)

  8. Review of nuclear air treatment system related License Event Reports for the period 1985 - 1987

    International Nuclear Information System (INIS)

    Jacox, J.W.

    1989-01-01

    This paper will continue the review of HVAC/NATS related LERS presented at past Air Cleaning Conferences by Dr. D. W. Moeller and his associates. The general approach and format are similar. LER abstracts from mid 1985 through 1987 were reviewed and those related to HVAC/NATS classified and analyzed. The categories were jointly developed by Dr. Moeller, Dr. Casper Sun and myself. In appropriate cases both primary and secondary categories fora problem are given. A basic listing by category and brief statistical review are presented. Additionally a number of categories are discussed in some detail. The categories chosen for specific review are intended to highlight particular problem areas. NUREG/CR-2000 License Event Report (LER) Compilation is the basis for the initial review and coding. In essentially all cases where an LER is classified as of interest the complete LER was obtained and reviewed in full. The intent of this paper is to provide a basis for the industry to document and analyze problem areas that require additional attention. It appears that about 15% of all LERS in the subject period are HVAC/NATS related. This figure is generally consistent with those reported at the 17th DOE Nuclear Air Cleaning Conference. It is hoped that such attention will allow additional resources to be allocated to upgrade systems, procedures and training as well as in some cases government regulation

  9. Extracting HEPs from Event Reports of Domestic Nuclear Power Plants-Case Study

    Energy Technology Data Exchange (ETDEWEB)

    Park, Jinkyun; Kim, Yochan; Jung, Wondea [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2016-10-15

    it is very important to soundly estimate the human error probability (HEP) of required tasks that could degrade the operational safety of systems. To this end, it is necessary to provide the HRA practitioners with the reliable catalog of HEPs. Unfortunately, one of the common issues raised by HRA practitioners is a lack of HRA data including HEPs. Therefore, many researchers are trying to provide reliable HRA data from diverse sources, such as (1) event reports reflecting the operational experience of domestic nuclear power plants (NPPs), and (2) human performance data observed from full- and/or partial-scope simulator exercises. It is evident that the contribution of human errors to the safety of socio-technical systems is very critical. For this reason, it is important for HRA practitioners to provide reliable HRA data including HEPs. Although a full-scope simulator can be used to collect valuable HRA data, it is still necessary to extract HRA data from the review of operational experience data. If so, it is possible to expect several benefits, such as the use of HRA data gathered from the operational experience of domestic NPPs as reference information to clarify the appropriateness of those collected from full-scope simulators.

  10. A hypothesis generation model of initiating events for nuclear power plant operators

    International Nuclear Information System (INIS)

    Sawhney, R.S.; Dodds, H.L.; Schryver, J.C.; Knee, H.E.

    1989-01-01

    The goal of existing alarm-filtering models is to provide the operator with the most accurate assessment of patterns of annunciated alarms. Some models are based on event-tree analysis, such as DuPont's Diagnosis of Multiple Alarms. Other models focus on improving hypothesis generation by deemphasizing alarms not relevant to the current plant scenario. Many such models utilize the alarm filtering system as a basis of dynamic prioritization. The Lisp-based alarm analysis model presented in this paper was developed for the Advanced Controls Program at Oak Ridge National Laboratory to dynamically prioritize hypotheses via an AFS by incorporating an unannunciated alarm analysis with other plant-based concepts. The objective of this effort is to develop an alarm analysis model that would allow greater flexibility and more accurate hypothesis generation than the prototype fault diagnosis model utilized in the Integrated Reactor Operator/System (INTEROPS) model. INTEROPS is a time-based predictive model of the nuclear power plant operator, which utilizes alarm information in a manner similar to the human operator. This is achieved by recoding the knowledge base from the personal computer-based expert system shell to a common Lisp structure, providing the ability to easily modify both the manner in which the knowledge is structured as well as the logic by which the program performs fault diagnosis

  11. Review of nuclear power reactor coolant system leakage events and leak detection requirements

    International Nuclear Information System (INIS)

    Chokshi, N.C.; Srinivasan, M.; Kupperman, D.S.; Krishnaswamy, P.

    2005-01-01

    In response to the vessel head event at the Davis-Besse reactor, the U.S. Nuclear Regulatory Commission (NRC) formed a Lessons Learned Task Force (LLTF). Four action plans were formulated to respond to the recommendations of the LLTF. The action plans involved efforts on barrier integrity, stress corrosion cracking (SCC), operating experience, and inspection and program management. One part of the action plan on barrier integrity was an assessment to identify potential safety benefits from changes in requirements pertaining to leakage in the reactor coolant system (RCS). In this effort, experiments and models were reviewed to identify correlations between crack size, crack-tip-opening displacement (CTOD), and leak rate in the RCS. Sensitivity studies using the Seepage Quantification of Upsets In Reactor Tubes (SQUIRT) code were carried out to correlate crack parameters, such as crack size, with leak rate for various types of crack configurations in RCS components. A database that identifies the leakage source, leakage rate, and resulting actions from RCS leaks discovered in U.S. light water reactors was developed. Humidity monitoring systems for detecting leakage and acoustic emission crack monitoring systems for the detection of crack initiation and growth before a leak occurs were also considered. New approaches to the detection of a leak in the reactor head region by monitoring boric-acid aerosols were also considered. (authors)

  12. Summary and bibliography of safety-related events at boiling-water nuclear power plants as reported in 1980

    Energy Technology Data Exchange (ETDEWEB)

    McCormack, K.E.; Gallaher, R.B.

    1982-03-01

    This document presents a bibliography that contains 100-word abstracts of event reports submitted to the US Nuclear Regulatory Commission concerning operational events that occurred at boiling-water-reactor nuclear power plants in 1980. The 1547 abstracts included on microfiche in this bibliography describe incidents, failures, and design or construction deficiencies that were experienced at the facilities. These abstracts are arranged alphabetically by reactor name and then chronologically for each reactor. Full-size keyword and permuted-title indexes to facilitate location of individual abstracts are provided following the text. Tables that summarize the information contained in the bibliography are also provided. The information in the tables includes a listing of the equipment items involved in the reported events and the associated number of reports for each item. Similar information is given for the various kinds of instrumentation and systems, causes of failures, deficiencies noted, and the time of occurrence (i.e., during refueling, operation, testing, or construction).

  13. Multiple Polyploidization Events across Asteraceae with Two Nested Events in the Early History Revealed by Nuclear Phylogenomics.

    Science.gov (United States)

    Huang, Chien-Hsun; Zhang, Caifei; Liu, Mian; Hu, Yi; Gao, Tiangang; Qi, Ji; Ma, Hong

    2016-11-01

    Biodiversity results from multiple evolutionary mechanisms, including genetic variation and natural selection. Whole-genome duplications (WGDs), or polyploidizations, provide opportunities for large-scale genetic modifications. Many evolutionarily successful lineages, including angiosperms and vertebrates, are ancient polyploids, suggesting that WGDs are a driving force in evolution. However, this hypothesis is challenged by the observed lower speciation and higher extinction rates of recently formed polyploids than diploids. Asteraceae includes about 10% of angiosperm species, is thus undoubtedly one of the most successful lineages and paleopolyploidization was suggested early in this family using a small number of datasets. Here, we used genes from 64 new transcriptome datasets and others to reconstruct a robust Asteraceae phylogeny, covering 73 species from 18 tribes in six subfamilies. We estimated their divergence times and further identified multiple potential ancient WGDs within several tribes and shared by the Heliantheae alliance, core Asteraceae (Asteroideae-Mutisioideae), and also with the sister family Calyceraceae. For two of the WGD events, there were subsequent great increases in biodiversity; the older one proceeded the divergence of at least 10 subfamilies within 10 My, with great variation in morphology and physiology, whereas the other was followed by extremely high species richness in the Heliantheae alliance clade. Our results provide different evidence for several WGDs in Asteraceae and reveal distinct association among WGD events, dramatic changes in environment and species radiations, providing a possible scenario for polyploids to overcome the disadvantages of WGDs and to evolve into lineages with high biodiversity. © The Author 2016. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution.

  14. I spy with my little eye - the detection of intentional contingency in early psychosis.

    Science.gov (United States)

    Fett, Anne-Kathrin J; González Berdugo, Clara Isabel; Hanssen, Esther; Lemmers-Jansen, Imke; Shergill, Sukhi S; Krabbendam, Lydia

    2015-01-01

    Paranoid delusions have been associated with a tendency to over-attribute intentionality and contingency to others' actions and incidental events in individuals with chronic psychosis. However, this hyper-associative perception bias has not been investigated in the early illness stages of psychosis, during which it may play a particularly crucial role in the formation of symptoms. We used an experimental paradigm with 20 short film clips of simple animate and inanimate shapes that either moved in a contingent or non-contingent manner to investigate the perception of contingency in 38 adolescents with early psychosis and 93 healthy control adolescents. Participants rated the contingency between the shapes' movements on a scale from 0 to 10. The data were analysed with multilevel regression analyses to account for repeated measures within subjects. There were no significant differences between patients and controls; both perceived the contingency of the shapes' movements similarly across all conditions and patients' contingency perception was unrelated to their levels of paranoid delusions. Contingency perception was unimpaired in patients with early psychosis, suggesting that it might still be intact in the early illness stages. Future studies should set out to determine whether the early illness stages could offer a window for interventions that counteract the development of hyper-associative perceptions of contingency.

  15. A comparison of analysis methods to estimate contingency strength.

    Science.gov (United States)

    Lloyd, Blair P; Staubitz, Johanna L; Tapp, Jon T

    2018-05-09

    To date, several data analysis methods have been used to estimate contingency strength, yet few studies have compared these methods directly. To compare the relative precision and sensitivity of four analysis methods (i.e., exhaustive event-based, nonexhaustive event-based, concurrent interval, concurrent+lag interval), we applied all methods to a simulated data set in which several response-dependent and response-independent schedules of reinforcement were programmed. We evaluated the degree to which contingency strength estimates produced from each method (a) corresponded with expected values for response-dependent schedules and (b) showed sensitivity to parametric manipulations of response-independent reinforcement. Results indicated both event-based methods produced contingency strength estimates that aligned with expected values for response-dependent schedules, but differed in sensitivity to response-independent reinforcement. The precision of interval-based methods varied by analysis method (concurrent vs. concurrent+lag) and schedule type (continuous vs. partial), and showed similar sensitivities to response-independent reinforcement. Recommendations and considerations for measuring contingencies are identified. © 2018 Society for the Experimental Analysis of Behavior.

  16. The sequence coding and search system: an approach for constructing and analyzing event sequences at commercial nuclear power plants

    International Nuclear Information System (INIS)

    Mays, G.T.

    1990-01-01

    The U.S. Nuclear Regulatory Commission (NRC) has recognized the importance of the collection, assessment, and feedback of operating experience data from commercial nuclear power plants and has centralized these activities in the Office for Analysis and Evaluation of Operational Data (AEOD). Such data is essential for performing safety and reliability analyses, especially analyses of trends and patterns to identify undesirable changes in plant performance at the earliest opportunity to implement corrective measures to preclude the occurrence of a more serious event. One of NRC's principal tools for collecting and evaluating operating experience data is the Sequence Coding and Search System (SCSS). The SCSS consists of a methodology for structuring event sequences and the requisite computer system to store and search the data. The source information for SCSS is the Licensee Event Report (LER), which is a legally required document. This paper describes the objectives of SCSS, the information it contains, and the format and approach for constructing SCSS event sequences. Examples are presented demonstrating the use of SCSS to support the analysis of LER data. The SCSS contains over 30,000 LERs describing events from 1980 through the present. Insights gained from working with a complex data system from the initial developmental stage to the point of a mature operating system are highlighted. Considerable experience has been gained in the areas of evolving and changing data requirements, staffing requirements, and quality control and quality assurance procedures for addressing consistency, software/hardware considerations for developing and maintaining a complex system, documentation requirements, and end-user needs. Two other approaches for constructing and evaluating event sequences are examined including the Accident Precursor Program (ASP) where sequences having the potential for core damage are identified and analyzed, and the Significant Event Compilation Tree

  17. Vagal tone during infant contingency learning and its disruption.

    Science.gov (United States)

    Sullivan, Margaret Wolan

    2016-04-01

    This study used contingency learning to examine changes in infants' vagal tone during learning and its disruption. The heart rate of 160 five-month-old infants was recorded continuously during the first of two training sessions as they experienced an audiovisual event contingent on their pulling. Maternal reports of infant temperament were also collected. Baseline vagal tone, a measure of parasympathetic regulation of the heart, was related to vagal levels during the infants' contingency learning session, but not to their learner status. Vagal tone levels did not vary significantly over session minutes. Instead, vagal tone levels were a function of both individual differences in learner status and infant soothability. Vagal levels of infants who learned in the initial session were similar regardless of their soothability; however, vagal levels of infants who learned in a subsequent session differed as a function of soothability. Additionally, vagal levels during contingency disruption were significantly higher among infants in this group who were more soothable as opposed to those who were less soothable. The results suggest that contingency learning and disruption is associated with stable vagal tone in the majority of infants, but that individual differences in attention processes and state associated with vagal tone may be most readily observed during the disruption phase. © 2015 Wiley Periodicals, Inc.

  18. Event Investigation

    International Nuclear Information System (INIS)

    Korosec, D.

    2000-01-01

    The events in the nuclear industry are investigated from the license point of view and from the regulatory side too. It is well known the importance of the event investigation. One of the main goals of such investigation is to prevent the circumstances leading to the event and the consequences of the event. The protection of the nuclear workers against nuclear hazard, and the protection of general public against dangerous effects of an event could be achieved by systematic approach to the event investigation. Both, the nuclear safety regulatory body and the licensee shall ensure that operational significant events are investigated in a systematic and technically sound manner to gather information pertaining to the probable causes of the event. One of the results should be appropriate feedback regarding the lessons of the experience to the regulatory body, nuclear industry and general public. In the present paper a general description of systematic approach to the event investigation is presented. The systematic approach to the event investigation works best where cooperation is present among the different divisions of the nuclear facility or regulatory body. By involving management and supervisors the safety office can usually improve their efforts in the whole process. The end result shall be a program which serves to prevent events and reduce the time and efforts solving the root cause which initiated each event. Selection of the proper method for the investigation and an adequate review of the findings and conclusions lead to the higher level of the overall nuclear safety. (author)

  19. Inevitability, contingency, and epistemic humility.

    Science.gov (United States)

    Kidd, Ian James

    2016-02-01

    This paper offers an epistemological framework for the debate about whether the results of scientific enquiry are inevitable or contingent. I argue in Sections 2 and 3 that inevitabilist stances are doubly guilty of epistemic hubris--a lack of epistemic humility--and that the real question concerns the scope and strength of our contingentism. The latter stages of the paper-Sections 4 and 5-address some epistemological and historiographical worries and sketch some examples of deep contingencies to guide further debate. I conclude by affirming that the concept of epistemic humility can usefully inform critical reflection on the contingency of the sciences and the practice of history of science. Copyright © 2015 Elsevier Ltd. All rights reserved.

  20. Nuclear security and radiological preparedness for the olympic games, athens 2004: lessons learned for organizing major public events.

    Science.gov (United States)

    Kamenopoulou, Vassiliki; Dimitriou, Panayiotis; Hourdakis, Constantine J; Maltezos, Antonios; Matikas, Theodore; Potiriadis, Constantinos; Camarinopoulos, Leonidas

    2006-10-01

    In light of the exceptional circumstances that arose from hosting the Olympic Games in Athens in 2004 and from recent terrorist events internationally, Greece attributes the highest priority to security issues. According to its statutory role, the Greek Atomic Energy Commission is responsible for emergency preparedness and response in case of nuclear and radiological events, and advises the Government on the measures and interventions necessary to protect the public. In this context, the Commission participated in the Nuclear, Radiological, Biological, and Chemical Threat National Emergency Plan, specially developed for the Olympic Games, and coordinated by the Olympic Games Security Division. The objective of this paper is to share the experience gained during the organization of the Olympic Games and to present the nuclear security program implemented prior to, during, and beyond the Games, in order to prevent, detect, assess, and respond to the threat of nuclear terrorism. This program adopted a multi-area coverage of nuclear security, including physical protection of nuclear and radiological facilities, prevention of smuggling of radioactive materials through borders, prevention of dispersion of these materials into the Olympic venues, enhancement of emergency preparedness and response to radiological events, upgrading of the technical infrastructure, establishment of new procedures for assessing the threat and responding to radiological incidents, and training personnel belonging to several organizations involved in the National Emergency Response Plan. Finally, the close cooperation of Greek Authorities with the International Atomic Energy Agency and the U.S. Department of Energy, under the coordination of the Greek Atomic Energy Commission, is also discussed.

  1. Tethered Satellite System Contingency Investigation Board

    Science.gov (United States)

    1992-11-01

    The Tethered Satellite System (TSS-1) was launched aboard the Space Shuttle Atlantis (STS-46) on July 31, 1992. During the attempted on-orbit operations, the Tethered Satellite System failed to deploy successfully beyond 256 meters. The satellite was retrieved successfully and was returned on August 6, 1992. The National Aeronautics and Space Administration (NASA) Associate Administrator for Space Flight formed the Tethered Satellite System (TSS-1) Contingency Investigation Board on August 12, 1992. The TSS-1 Contingency Investigation Board was asked to review the anomalies which occurred, to determine the probable cause, and to recommend corrective measures to prevent recurrence. The board was supported by the TSS Systems Working group as identified in MSFC-TSS-11-90, 'Tethered Satellite System (TSS) Contingency Plan'. The board identified five anomalies for investigation: initial failure to retract the U2 umbilical; initial failure to flyaway; unplanned tether deployment stop at 179 meters; unplanned tether deployment stop at 256 meters; and failure to move tether in either direction at 224 meters. Initial observations of the returned flight hardware revealed evidence of mechanical interference by a bolt with the level wind mechanism travel as well as a helical shaped wrap of tether which indicated that the tether had been unwound from the reel beyond the travel by the level wind mechanism. Examination of the detailed mission events from flight data and mission logs related to the initial failure to flyaway and the failure to move in either direction at 224 meters, together with known preflight concerns regarding slack tether, focused the assessment of these anomalies on the upper tether control mechanism. After the second meeting, the board requested the working group to complete and validate a detailed integrated mission sequence to focus the fault tree analysis on a stuck U2 umbilical, level wind mechanical interference, and slack tether in upper tether

  2. Single event upset mitigation techniques for FPGAs utilized in nuclear power plant digital instrumentation and control

    International Nuclear Information System (INIS)

    Wang Xin; Holbert, Keith E.; Clark, Lawrence T.

    2011-01-01

    Highlights: → Triple modular redundancy (TMR) implementation is the best solution for digital I and C. → Maximal probability of two simultaneous errors with TMR maximum partition is 4.44%. → Dual modular redundancy minimum logic partitioning design is an additional option. - Abstract: Field programmable gate arrays (FPGAs) are integrated circuits being increasingly used for digital instrumentation and control (I and C) in nuclear power plants (NPPs) because of low cost, re-configurability and low design turn-around time. However, to ensure reliability, proper design techniques must be employed since the memory and logic in FPGAs are susceptible to single event upsets (SEUs). Triple modular redundancy (TMR) has become a common SEU mitigation design technique because of its straightforward implementation and reliable results. Partitioned TMR approaches are introduced in this paper, and formulae derived indicate that the maximum probability of two simultaneous errors [P E ] max is inversely proportional to the number of logic partitions in a TMR design, when each redundant logic block in every logic partition has the same number of sensitive nodes. However, the maximum logic partitioning design cannot completely eliminate the possibility of two simultaneous upsets. For the example test circuit it is found that [P E ] max is reduced dramatically from 66.67% for minimum logic partitioning to 4.44% for maximum logic partitioning. Because TMR introduces significant overhead due to its full hardware redundancy, a dual modular redundancy approach is also examined for application to less demanding situations. By comparative analysis this study reaches the conclusion that the maximum logic partitioning TMR implementation is the best solution for digital I and C applications in NPPs where obtaining robustness is of the highest importance, despite its higher area overhead.

  3. Uncertainties for seismic moment tensors and applications to nuclear explosions, volcanic events, and earthquakes

    Science.gov (United States)

    Tape, C.; Alvizuri, C. R.; Silwal, V.; Tape, W.

    2017-12-01

    When considered as a point source, a seismic source can be characterized in terms of its origin time, hypocenter, moment tensor, and source time function. The seismologist's task is to estimate these parameters--and their uncertainties--from three-component ground motion recorded at irregularly spaced stations. We will focus on one portion of this problem: the estimation of the moment tensor and its uncertainties. With magnitude estimated separately, we are left with five parameters describing the normalized moment tensor. A lune of normalized eigenvalue triples can be used to visualize the two parameters (lune longitude and lune latitude) describing the source type, while the conventional strike, dip, and rake angles can be used to characterize the orientation. Slight modifications of these five parameters lead to a uniform parameterization of moment tensors--uniform in the sense that equal volumes in the coordinate domain of the parameterization correspond to equal volumes of moment tensors. For a moment tensor m that we have inferred from seismic data for an earthquake, we define P(V) to be the probability that the true moment tensor for the earthquake lies in the neighborhood of m that has fractional volume V. The average value of P(V) is then a measure of our confidence in our inference of m. The calculation of P(V) requires knowing both the probability P(w) and the fractional volume V(w) of the set of moment tensors within a given angular radius w of m. We apply this approach to several different data sets, including nuclear explosions from the Nevada Test Site, volcanic events from Uturuncu (Bolivia), and earthquakes. Several challenges remain: choosing an appropriate misfit function, handling time shifts between data and synthetic waveforms, and extending the uncertainty estimation to include more source parameters (e.g., hypocenter and source time function).

  4. GC Side Event: Nuclear Operators Forum: Challenges in Human Resources Management for Sustainable Nuclear Power Generation. Presentations

    International Nuclear Information System (INIS)

    2017-01-01

    This year’s Forum focussed on human resources challenges and necessary actions to support the future of nuclear energy, including building and maintaining the workforce, economic challenges and new ways of learning

  5. Operational analysis and improvement of a spent nuclear fuel handling and treatment facility using discrete event simulation

    International Nuclear Information System (INIS)

    Garcia, H.E.

    2000-01-01

    Spent nuclear fuel handling and treatment often require facilities with a high level of operational complexity. Simulation models can reveal undesirable characteristics and production problems before they become readily apparent during system operations. The value of this approach is illustrated here through an operational study, using discrete event modeling techniques, to analyze the Fuel Conditioning Facility at Argonne National Laboratory and to identify enhanced nuclear waste treatment configurations. The modeling approach and results of what-if studies are discussed. An example on how to improve productivity is presented.

  6. Nuclear data relevant to single event upsets in semiconductor memories induced by cosmic-ray neutrons and protons

    International Nuclear Information System (INIS)

    Watanabe, Yukinobu

    2008-01-01

    The role of nuclear data is examined in the study of single event upset (SEU) phenomena in semiconductor memories caused by cosmic-ray neutrons and protons. Neutron and proton SEU cross sections are calculated with a simplified semi-empirical model using experimental heavy-ion SEU cross-sections and a dedicated database of neutron and proton induced reactions on 28 Si. Some impacts of the nuclear reaction data on SEU simulation are analyzed by investigating relative contribution of secondary ions and neutron elastic scattering to SEU and influence of simultaneous multiple ions emission on SEU. (author)

  7. Analysis of nuclear and radiological events. Textbook for lecture in graduate school of engineering in the University of Tokyo

    International Nuclear Information System (INIS)

    Watanabe, Norio

    2007-02-01

    The Japan Atomic Energy Agency is carrying out the cooperative activity by providing specialized educational and training staff and making our facilities available for the graduate school of engineering in The University of Tokyo as part of developing human resources in nuclear technology. This report is prepared as a textbook for the lecture in the graduate school of engineering in The University of Tokyo and provides the outlines of activities on the analysis of nuclear and radiological events and analysis methods as well as the summaries of major incidents and accidents that occurred. (author)

  8. Contingent Employment in the Netherlands

    OpenAIRE

    Pot, F.; Koene, Bas; Paauwe, Jaap

    2001-01-01

    textabstractIn the last decade the Dutch labour market has demonstrated an admirable capacity to generate jobs. Consequently, the unemployment rate has significantly decreased. However, the newly generated jobs are a-typical in the sense that they are not full-time jobs based on open-ended contracts. Instead, the job growth has relied on the growth of part-time and contingent jobs. While the creation of part-time jobs seems to be employee-driven, contingent employment, in contrast, seems to b...

  9. Compilation of data concerning know and suspected water hammer events in nuclear power plants, CY 1969

    International Nuclear Information System (INIS)

    Chapman, R.L.; Christensen, D.D.; Dafoe, R.E.; Hanner, O.M.; Wells, M.E.

    1981-05-01

    This report compiles data concerning known and suspected water hammer events reported by BWR and PWR power plants in the United States from January 1, 1969, to May 1, 1981. This information is summarized for each event and is tabulated for all events by plant, plant type, year of occurrence, type of water hammer, system affected, basis/cause for the event, and damage incurred. Information is also included from other events not specifically identified as water hammer related. These other events involved vibration and/or system components similar to those involved in the water hammer events. The other events are included to ensure completeness of the report, but are not used to point out particular facts or trends. This report does not evaluate findings abstracted from the data

  10. The sequence coding and search system: An approach for constructing and analyzing event sequences at commercial nuclear power plants

    International Nuclear Information System (INIS)

    Mays, G.T.

    1989-04-01

    The US Nuclear Regulatory Commission (NRC) has recognized the importance of the collection, assessment, and feedstock of operating experience data from commercial nuclear power plants and has centralized these activities in the Office for Analysis and Evaluation of Operational Data (AEOD). Such data is essential for performing safety and reliability analyses, especially analyses of trends and patterns to identify undesirable changes in plant performance at the earliest opportunity to implement corrective measures to preclude the occurrences of a more serious event. One of NRC's principal tools for collecting and evaluating operating experience data is the Sequence Coding and Search System (SCSS). The SCSS consists of a methodology for structuring event sequences and the requisite computer system to store and search the data. The source information for SCSS is the Licensee Event Report (LER), which is a legally required document. This paper describes the objective SCSS, the information it contains, and the format and approach for constructuring SCSS event sequences. Examples are presented demonstrating the use SCSS to support the analysis of LER data. The SCSS contains over 30,000 LERs describing events from 1980 through the present. Insights gained from working with a complex data system from the initial developmental stage to the point of a mature operating system are highlighted

  11. Analysis of loss of offsite power events reported in nuclear power plants

    Energy Technology Data Exchange (ETDEWEB)

    Volkanovski, Andrija, E-mail: Andrija.VOLKANOVSKI@ec.europa.eu [European Commission, Joint Research Centre, Institute for Energy and Transport, P.O. Box 2, NL-1755 ZG Petten (Netherlands); Ballesteros Avila, Antonio; Peinador Veira, Miguel [European Commission, Joint Research Centre, Institute for Energy and Transport, P.O. Box 2, NL-1755 ZG Petten (Netherlands); Kančev, Duško [Kernkraftwerk Goesgen-Daeniken AG, CH-4658 Daeniken (Switzerland); Maqua, Michael [Gesellschaft für Anlagen-und-Reaktorsicherheit (GRS) gGmbH, Schwertnergasse 1, 50667 Köln (Germany); Stephan, Jean-Luc [Institut de Radioprotection et de Sûreté Nucléaire (IRSN), BP 17 – 92262 Fontenay-aux-Roses Cedex (France)

    2016-10-15

    Highlights: • Loss of offsite power events were identified in four databases. • Engineering analysis of relevant events was done. • The dominant root cause for LOOP are human failures. • Improved maintenance procedures can decrease the number of LOOP events. - Abstract: This paper presents the results of analysis of the loss of offsite power events (LOOP) in four databases of operational events. The screened databases include: the Gesellschaft für Anlagen und Reaktorsicherheit mbH (GRS) and Institut de Radioprotection et de Sûreté Nucléaire (IRSN) databases, the IAEA International Reporting System for Operating Experience (IRS) and the U.S. Licensee Event Reports (LER). In total 228 relevant loss of offsite power events were identified in the IRSN database, 190 in the GRS database, 120 in U.S. LER and 52 in IRS database. Identified events were classified in predefined categories. Obtained results show that the largest percentage of LOOP events is registered during On power operational mode and lasted for two minutes or more. The plant centered events is the main contributor to LOOP events identified in IRSN, GRS and IAEA IRS database. The switchyard centered events are the main contributor in events registered in the NRC LER database. The main type of failed equipment is switchyard failures in IRSN and IAEA IRS, main or secondary lines in NRC LER and busbar failures in GRS database. The dominant root cause for the LOOP events are human failures during test, inspection and maintenance followed by human failures due to the insufficient or wrong procedures. The largest number of LOOP events resulted in reactor trip followed by EDG start. The actions that can result in reduction of the number of LOOP events and minimize consequences on plant safety are identified and presented.

  12. A cosmic-ray nuclear event with an anomalously strong concentration of energy and particles in the central region

    International Nuclear Information System (INIS)

    Amato, N.M.; Arata, N.; Maldonado, R.H.C.

    1987-01-01

    A cosmic-ray-induced nuclear event detected in an emulsion chamber is described. The event consist of 217 shower cores with ΣEγ=1.275 TeV. In a logarithmic scale, energy and particles are emitted most densely at the small lateral distance corresponding to 0.5 mm; 77% of the total energy and 61% of the total multiplicity are inside a radius of 0.65 cm. The shower cores in the central region show exponential-type energy distribution and nonisotropic azimuthal distribution

  13. Proceeding of 31st domestic symposium on failure events and integrity evaluation of nuclear power generation facilities

    International Nuclear Information System (INIS)

    2003-07-01

    As the 31st domestic symposium of Atomic Energy Research Committee, the Japan Welding Engineering Society, the symposium was held titled as 'Damage events and integrity evaluations of nuclear power facilities'. Six speakers gave lectures titled as 'Damages of structural materials in the LWR plants and their measures', 'Inspection and integrity evaluation method of SCC in the BWR plants', 'Measures with chloride SCC of piping', 'High cycle fatigue damage events of small diameter pipes and their measures', 'Management of SCC in in-core instrumentation thimbles' and 'Japanese lost ten years and American and other leaps'. (T. Tanaka)

  14. Formulation of nuclear safety under various induced events. Part 1. Current status and challenges for risk-informed activities in nuclear safety

    International Nuclear Information System (INIS)

    Itoi, Tatsuya; Hayashi, Kentaro; Yamato, Masaaki

    2016-01-01

    The Nuclear Safety Subcommittee published in March 2013 a report on 'Seminar on the Fukushima Daiichi Nuclear Power Station accident' (hereinafter referred to as Seminar Report), and has thereafter continued discussions on the challenges that were pointed out in Seminar Report as the target of discussions. This commentary series summarizes the current situation and challenges for the ideal way of nuclear safety against a variety of causal events as one of the above challenges. This paper, as Part 1 of the above theme, firstly summarizes the current state of the challenges of regulatory bodies and business operators who are engaging risk information utilization. It secondly discusses the future risk information utilization of regulations and business operators, realization of integrated decision-making process, timeliness and promptness required in decision-making, and future efforts including incentives. (A.O.)

  15. Contingency Theories of Leadership: A Study.

    Science.gov (United States)

    Saha, Sunhir K.

    1979-01-01

    Some of the major contingency theories of leadership are reviewed; some results from the author's study of Fiedler's contingency model are reported; and some thoughts for the future of leadership research are provided. (Author/MLF)

  16. Organization of public authorities in France for the event of an incident or accident involving nuclear safety: Simulation of a nuclear crisis

    International Nuclear Information System (INIS)

    Cartigny, J.; Majorel, Y.

    1986-01-01

    The French nuclear safety regulations lay down the action to be taken in the event of an incident or accident involving the types of radiological hazard that could arise in a nuclear installation or during the transport of radioactive material. The organization established for this purpose is designed to ensure that the technical measures taken by the authorities responsible for nuclear safety, radiation protection, public order and public safety are fully effective. The Interministerial Nuclear Safety Committee (Comite interministeriel de la securite nucleaire), which reports to the Prime Minister, co-ordinates the measures taken by the public authorities. The public authorities and the operators together organize exercises designed to verify the whole complex of measures foreseen in the event of an incident or accident. These exercises, which have been carried out in a systematic manner in France for some years, are based on scenarios which are as realistic as possible and enable the following objectives to be achieved: (1) analysis of the crisis apparatus (ORSECRAD plans, individual intervention plans, information conventions); (2) uncovering gaps or inadequacies; (3) arrangements for interchange of information between the various participants whose responsibilities involve them in the emergency; and (4) allowance for the information requirements of the media and the population. The information drawn from these exercises enables the various procedures to be improved step by step. (author)

  17. Development of advanced automatic control system for nuclear ship. 2. Perfect automatic operation after reactor scram events

    International Nuclear Information System (INIS)

    Yabuuchi, Noriaki; Nakazawa, Toshio; Takahashi, Hiroki; Shimazaki, Junya; Hoshi, Tsutao

    1997-11-01

    An automatic operation system has been developed for the purpose of realizing a perfect automatic plant operation after reactor scram events. The goal of the automatic operation after a reactor scram event is to bring the reactor hot stand-by condition automatically. The basic functions of this system are as follows; to monitor actions of the equipments of safety actions after a reactor scram, to control necessary control equipments to bring a reactor to a hot stand-by condition automatically, and to energize a decay heat removal system. The performance evaluation on this system was carried out by comparing the results using to Nuclear Ship Engineering Simulation System (NESSY) and the those measured in the scram test of the nuclear ship 'Mutsu'. As the result, it was showed that this system had the sufficient performance to bring a reactor to a hot syand-by condition quickly and safety. (author)

  18. Development of advanced automatic control system for nuclear ship. 2. Perfect automatic operation after reactor scram events

    Energy Technology Data Exchange (ETDEWEB)

    Yabuuchi, Noriaki; Nakazawa, Toshio; Takahashi, Hiroki; Shimazaki, Junya; Hoshi, Tsutao [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment

    1997-11-01

    An automatic operation system has been developed for the purpose of realizing a perfect automatic plant operation after reactor scram events. The goal of the automatic operation after a reactor scram event is to bring the reactor hot stand-by condition automatically. The basic functions of this system are as follows; to monitor actions of the equipments of safety actions after a reactor scram, to control necessary control equipments to bring a reactor to a hot stand-by condition automatically, and to energize a decay heat removal system. The performance evaluation on this system was carried out by comparing the results using to Nuclear Ship Engineering Simulation System (NESSY) and the those measured in the scram test of the nuclear ship `Mutsu`. As the result, it was showed that this system had the sufficient performance to bring a reactor to a hot syand-by condition quickly and safety. (author)

  19. The OECD/NEA workshop on the indemnification of nuclear damage in the event of a nuclear accident

    International Nuclear Information System (INIS)

    Wagstaff, F.

    2002-01-01

    Since 1993, the OECD Nuclear Energy Agency (OECD/NEA) has run the International Nuclear Emergency Exercise (INEX) Program. The program serves to discuss an effective accident management approach on the basis of a simulated nuclear accident situation together with the states involved and their institutions, and also elaborate measures for its further improvement. At the present time, the INEX Program has reached Phase 3 in which, for the first time, also aspects of liability for the consequences of accidents were included. These aspects were made the subject of a workshop held after an emergency exercise. The scenario covered was based on an INES level-4 accident in the French Gravelines Nuclear Power Station situated close to the French-Belgian border. The workshop dealt with these topics, among others: the application of the Paris Convention on Third Party Liability, the Brussels Supplementary Convention, and the Vienna Convention on Civil Liability for Nuclear Damage as well as the Supplementary Compensation Convention of 1997. It was seen that there was a clear need for further discussion, especially to shed more light on the interrelationship of these treaties. (orig.) [de

  20. Study pertaining to the distribution of iodine pills in the event of a nuclear mishap at the Gentilly II Station

    International Nuclear Information System (INIS)

    Corriveau, R.

    1992-01-01

    This study seeks to understand how volunteers, whose task it is to distribute iodine pills in the event of a nuclear mishap, are likely to react in such a situation. Our postulate is that the uniform application of preventative measures in an emergency situation requires that volunteers adhere to the principles of the ideological apparatus (civil authority). Our findings are that current measures are inadequate for an effective emergency strategy. (author)

  1. Defense plan of Hydro-Quebec for extreme contingencies

    International Nuclear Information System (INIS)

    Trudel, Guilles; Bernard, Serge; Portales, Esteban

    2000-01-01

    In the last years, Hydro-Quebec it undertook an important program to improve the dependability of their net of energy transport. They concentrated the efforts on increasing the capacity of the net resist in the event of carries to an extreme contingency caused in general by multiple incidents or for successive disconnection of the lines of energy transport. To neutralize these contingencies, Hydro-Quebec it adopted a series of special measures that are contained under the general title of Plan of Defense for Extreme Contingencies. The objective of this plan is to detect the incidents that surpass the capacity of the net. It is completely automatic and it is based mainly in: A system of automatic disconnection of generation and tele-shot of loads; A system of automatic maneuver (opening and closing) of inductances shunt of 735 kw; A system of disconnection of loads for low voltage; A system of disconnection of loads for low frequency. The present document summarizes the orientations that there is taking Hydro-Quebec to protect its net in the event of extreme contingencies and it describes the different automatism that they are adopts, in particular the system automatic disconnection of generation and tele-shot of loads (RPTC) that is one of the main components of the defense plan. The system RPTC detects the simultaneous loss of several lines directly in 15 substations of 735 kw. It understands four places of automatic disconnection of generation and a centralized system of tele-shot of loads

  2. APPROPRIATE ALLOCATION OF CONTINGENCY USING RISK ANALYSIS METHODOLOGY

    Directory of Open Access Journals (Sweden)

    Andi Andi

    2004-01-01

    Full Text Available Many cost overruns in the world of construction are attributable to either unforeseen events or foreseen events for which uncertainty was not appropriately accommodated. It is argued that a significant improvement to project management performance may result from greater attention to the process of analyzing project risks. The objective of this paper is to propose a risk analysis methodology for appropriate allocation of contingency in project cost estimation. In the first step, project risks will be identified. Influence diagramming technique is employed to identify and to show how the risks affect the project cost elements and also the relationships among the risks themselves. The second step is to assess the project costs with regards to the risks under consideration. Using a linguistic approach, the degree of uncertainty of identified project risks is assessed and quantified. The problem of dependency between risks is taken into consideration during this analysis. For the final step, as the main purpose of this paper, a method for allocating appropriate contingency is presented. Two types of contingencies, i.e. project contingency and management reserve are proposed to accommodate the risks. An illustrative example is presented at the end to show the application of the methodology.

  3. Damping values for nuclear power plant piping during seismic events and fluid-induced transients

    International Nuclear Information System (INIS)

    Ware, A.G.

    1986-01-01

    For several years the Idaho National Engineering Laboratory (INEL) has been assisting the United States Nuclear Regulatory Commission (USNRC) in efforts to establish best-estimate damping values for use in the dynamic analysis of nuclear power plant piping systems. Data from a number of piping vibration tests conducted at facilities worldwide (including the INEL) have been collected, evaluated, reported, and placed in a nuclear piping data bank at the INEL. These data are being used to justify changes in allowable damping values for use in nuclear piping design, thus making piping systems safer, less costly, and easier to inspect and maintain

  4. Contingency Teaching during Close Reading

    Science.gov (United States)

    Fisher, Douglas; Frey, Nancy

    2015-01-01

    12 teachers were interviewed and observed as they engaged students in close reading. We analyzed their responses and instruction to determine the scaffolds that were used as well as the contingency teaching plans they implemented when students were unable to understand the text.

  5. Breakdown concepts for contingency tables

    NARCIS (Netherlands)

    Kuhnt, S.

    2010-01-01

    Loglinear Poisson models are commonly used to analyse contingency tables. So far, robustness of parameter estimators as well as outlier detection have rarely been treated in this context. We start with finite-sample breakdown points. We yield that the breakdown point of mean value estimators

  6. Developing standardized facility contingency plans

    International Nuclear Information System (INIS)

    Davidson, D.A.

    1993-01-01

    Texaco consists of several operating departments that are, in effect, independent companies. Each of these departments is responsible for complying with all environmental laws and regulations. This includes the preparation by each facility to respond to an oil spill at that location. For larger spills, however, management of the response will rest with corporate regional response teams. Personnel from all departments make up the regional teams. In 1990, Congress passed the Oil Pollution Act. In 1991, the US Coast Guard began developing oil spill response contingency plan regulations, which they are still working on. Meanwhile, four of the five west coast states have also passed laws requiring contingency plans. (Only Hawaii has chosen to wait and see what the federal regulations will entail). Three of the states have already adopted regulations. Given these laws and regulations, along with its corporate structure, Texaco addressed the need to standardize local facility plans as well as its response organization. This paper discusses how, by working together, the Texaco corporate international oil spill response staff and the Texaco western region on-scene commander developed: A standard contingency plan format crossing corporate boundaries and meeting federal and state requirements. A response organization applicable to any size facility or spill. A strategy to sell the standard contingency plan and response organization to the operating units

  7. Lessons in Contingent, Recursive Humility

    Science.gov (United States)

    Vagle, Mark D.

    2011-01-01

    In this article, the author argues that critical work in teacher education should begin with teacher educators turning a critical eye on their own practices. The author uses Lesko's conception of contingent, recursive growth and change to analyze a lesson he observed as part of a phenomenological study aimed at understanding more about what it is…

  8. Job satisfaction and contingent employment

    NARCIS (Netherlands)

    de Graaf-Zijl, M.

    2012-01-01

    This paper analyses job satisfaction as an aggregate of satisfaction with several job aspects, with special focus on the influence of contingent-employment contracts. Fixed-effect analysis is applied on a longitudinal sample of Dutch employees in four work arrangements: regular, fixed-term, on-call

  9. A Profile of Contingent Workers.

    Science.gov (United States)

    Polivka, Anne E.

    1996-01-01

    Based on data from the supplement to the February 1995 Current Population Survey, contingent workers were more likely to be female, black, young, enrolled in school, and employed in services and construction industries than were noncontingent workers. More than 10% were teachers. (Author)

  10. How Precarious Is Contingent Work?

    DEFF Research Database (Denmark)

    Scheuer, Steen

    2015-01-01

    agree. This study focuses on a number of non-pay conditions for contingent employees, compared to permanent staff, under the assumption that these conditions are cumulatively negative. The article is based on utilizes a survey of app.4,900 employees (response rate 57%), asking questions concerning...

  11. 48 CFR 18.201 - Contingency operation.

    Science.gov (United States)

    2010-10-01

    ... 48 Federal Acquisition Regulations System 1 2010-10-01 2010-10-01 false Contingency operation. 18... METHODS AND CONTRACT TYPES EMERGENCY ACQUISITIONS Emergency Acquisition Flexibilities 18.201 Contingency operation. (a) Contingency operation is defined in 2.101. (b) Micro-purchase threshold. The threshold...

  12. 48 CFR 218.201 - Contingency operation.

    Science.gov (United States)

    2010-10-01

    ... 48 Federal Acquisition Regulations System 3 2010-10-01 2010-10-01 false Contingency operation. 218... Flexibilities 218.201 Contingency operation. (1) Selection, appointment, and termination of appointment... in a contingency contracting force. See 201.603-2(2). (2) Policy for unique item identification...

  13. 49 CFR 1542.301 - Contingency plan.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 9 2010-10-01 2010-10-01 false Contingency plan. 1542.301 Section 1542.301..., DEPARTMENT OF HOMELAND SECURITY CIVIL AVIATION SECURITY AIRPORT SECURITY Contingency Measures § 1542.301 Contingency plan. (a) Each airport operator required to have a security program under § 1542.103(a) and (b...

  14. Plant specific safety inspection of German nuclear power plants taking into account the Fukushima-I (Japan) events

    International Nuclear Information System (INIS)

    2011-01-01

    The German Parliament requested (17 March 2011) a comprehensive inspection of German nuclear power plants. For this purpose independent expert commissions should perform a new risk analysis of all German NPPS and nuclear installations with respect to the lessons learned from the Fukushima (Japan) events and other extraordinary damage scenarios. The Reactor safety commission (RSK) was assigned by the German Bundesamt fuer Strahlenschutz to develop a catalogue of requirements for this safety inspection. The contribution summarizes the required inspection volume (status 30.03.2011) including the following events: natural events like earth quakes, floods, weather-based consequences and possible superposition. Additionally the following assumptions have to be considered: event independent postulated common failures or systematic faults, station blackout larger than 2 hours, long-term failure of the auxiliary cooling water supply; aggravating boundary conditions for the performance of emergency measures (non-availability of power supply), hydrogen generation and detonation hazard, restricted personnel availability, non-accessibility due to high radiation levels, impeded technical support from outside. (orig.)

  15. Procedures as a Contributing Factor to Events in the Swedish Nuclear Power Plants. Analysis of a Database with Licensee Event Reports 1995-1999

    International Nuclear Information System (INIS)

    Bento, Jean-Pierre

    2002-12-01

    The operating experience from the twelve Swedish nuclear power units has been reviewed for the years 1995 - 1999 with respect to events - both Scrams and Licensee Event Reports, LERs - to which deficient procedure has been a contributing cause. In the present context 'Procedure' is defined as all written documentation used for the planning, performance and control of the tasks necessary for the operation and maintenance of the plants. The study has used an MTO-database (Man - Technology - Organisation) containing, for the five years studied, 42 MTO-related scrams out of 87 occurred scrams, and about 800 MTO-related LERs out of 2000 reported LERs. On an average, deficient procedures contribute to approximately 0,2 scram/unit/ year and to slightly more than three LERs/unit/year. Presented differently, procedure related scrams amount to 15% of the total number of scrams and to 31% of the MTO-related scrams. Similarly procedure related LERs amount to 10% of the total number of LERs and to 25% of the MTO-related LERs. For the most frequent work types performed at the plants, procedure related LERs are - in decreasing order - associated with tasks performed during maintenance, modification, testing and operation. However, for the latest year studied almost as many procedure related LERs are associated with modification tasks as with the three other work types together. A further analysis indicates that 'Deficient procedure content' is, by far, the dominating underlying cause contributing to procedure related scrams and LERs. The study also discusses the coupling between procedure related scrams/LERs, power operation and refuelling outages, and Common Cause Failures, CCF. An overall conclusion is that procedure related events in the Swedish nuclear power plants do not, on a national scale, represent an alarming issue. Significant and sustained efforts have been and are made at most units to improve the quality of procedures. However, a few units exhibit a noticeable

  16. The nuclear present. A guide to recent books on nuclear war, weapons, the peace movement, and related issues, with a chronology of nuclear events, 1789-1991

    International Nuclear Information System (INIS)

    Burns, G.

    1992-01-01

    The Nuclear Present brings the interested reader up-to-date on significant English-language books about nuclear weapons and related topics, identifying primarily important works of nuclear non-fiction that have come out since 1984. Each reference has a paragraph of comment about its subject and value. General organizational areas include the following: Reference Works; Nuclear weapons and Nuclear war (14 sub-headings including overviews, development, effects, tests, arms race, prospectives, legal considerations etc.); Strategy; proliferation; Stratigic Defense; Arms control and disarmament; ethical, pholosophical and religous perspectives; new paths to peace; periodic guide; the Chernobyl Disaster. An extensive Nuclear Chronology (1789-1991) written by the author allows a fairly detailed sense of the historical record of nuclear weapons, including testing, manufacture, use and movements for arms control and disarmament

  17. A cosmic-ray nuclear event with an anomalously strong concentration of energy and particles in the central region

    International Nuclear Information System (INIS)

    Amato, N.M.; Arata, N.; Maldonado, R.H.C.

    1986-01-01

    A cosmic-ray induced nuclear event detected in the emulsion chamber is described. The event consists of 217 shower cores with ΣEγ = 1,275 TeV. In log scale, energy and particles are emitted most densely at the small lateral distance corresponding to 0.5 mm; 77 % of the total energy and 61 % of the total multiplicity are inside the radius of 0.65 cm. The shower cores in the central region show exponential-type energy distribution and non-isotropic azimuthal distribution. This event indicates a possibility that phenomena of large transverse momentum could happen to produce a strong concentration of energy and particles in the very forward direction. (Authors) [pt

  18. Evidence of children's vulnerability to radiation in the context of radiological/nuclear events and considerations for emergency response.

    Science.gov (United States)

    Lane, Rachel; Reinhardt, Pascale; Thompson, Patsy

    2010-11-01

    International organisations, such as International Atomic Energy Agency, United Nations Scientific Committee on the Effects of Atomic Radiation and World Health Organisation, together with committees of experts such as Biological Effects of Ionising Radiation and Committee on Medical Aspects of Radiation in the Environment, have assessed the effects of radiation on large exposed populations (Chernobyl accident, and Hiroshima/Nagasaki atomic bombings) and on nuclear energy workers and people living near nuclear facilities. Childhood and in utero exposure to moderate and high levels of ionizing radiation, such as those experienced during the atomic bombings of Japan, or from radiotherapy, is an established cause of leukaemia and solid cancer. There is no evidence of increase in solid cancers (excluding thyroid cancer) or leukaemia in the children from Chernobyl, and no evident link between worker's exposure to radiation and leukaemia in their offspring or with the presence of leukaemia clusters around nuclear power plants. It has also not been possible to demonstrate the evidence of radiation hereditary effects in human populations. In accordance with international guidance, Canadian Nuclear Safety Commission recommends optimisation of protection strategies to reduce doses to children. The development of credible radiological/nuclear event scenarios would assist in identifying probable sources of radioactivity and pathways of exposure for children. Such scenarios should then be used to identify protection strategies appropriate for children.

  19. Re-assessment of road accident data-analysis policy : applying theory from involuntary, high-consequence, low-probability events like nuclear power plant meltdowns to voluntary, low-consequence, high-probability events like traffic accidents

    Science.gov (United States)

    2002-02-01

    This report examines the literature on involuntary, high-consequence, low-probability (IHL) events like nuclear power plant meltdowns to determine what can be applied to the problem of voluntary, low-consequence high-probability (VLH) events like tra...

  20. Areas for US-India civilian nuclear cooperation to prevent/mitigate radiological events.

    Energy Technology Data Exchange (ETDEWEB)

    Balachandran, Gopalan; Forden, Geoffrey Ethan

    2013-01-01

    Over the decades, India and the United States have had very little formal collaboration on nuclear issues. Partly this was because neither country needed collaboration to make progress in the nuclear field. But it was also due, in part, to the concerns both countries had about the others intentions. Now that the U.S.-India Deal on nuclear collaboration has been signed and the Hyde Act passed in the United States, it is possible to recognize that both countries can benefit from such nuclear collaboration, especially if it starts with issues important to both countries that do not touch on strategic systems. Fortunately, there are many noncontroversial areas for collaboration. This study, funded by the U.S. State Department, has identified a number of areas in the prevention of and response to radiological incidents where such collaboration could take place.

  1. Nuclear and energies - Synthesis of striking events from June to November 2012. Nr 60 - December 2012

    International Nuclear Information System (INIS)

    Lenail, Bernard; Ducroux, Guy; Seyve, Claude; Fromant, Bernard; Greneche, Dominique; Gollion, Jacques; Raisonnier, Daniele; Lepine, Gerard; Vandevoir, Roger

    2012-12-01

    A first article comments the debate on the environment and on energy transition, and the Japanese objective to phase out nuclear. The second article comments the evolution of the energy sector (IAEA position, energy transition in the USA, according to the European vision and in France. Then several articles deal with the nuclear sector: uranium market, mining and processing, perspectives and news for nuclear reactors in France and many other countries in the world, access to the INIS database, activities and news related to the front-end part of the fuel cycle in various countries, and to R and D. A last article addresses the impact of the nuclear sector on the environment and public health

  2. Device for bonding iodine in the event of nuclear reactor accidents

    International Nuclear Information System (INIS)

    Hladik, O.

    1988-01-01

    A device for bonding iodine, in particular radioiodine released during nuclear reactor accidents, is presented. Radioiodine is bonded, even at high temperatures, so that it is neither volatile nor soluble

  3. Fuzzy-set based contingency ranking

    International Nuclear Information System (INIS)

    Hsu, Y.Y.; Kuo, H.C.

    1992-01-01

    In this paper, a new approach based on fuzzy set theory is developed for contingency ranking of Taiwan power system. To examine whether a power system can remain in a secure and reliable operating state under contingency conditions, those contingency cases that will result in loss-of-load, loss-of generation, or islanding are first identified. Then 1P-1Q iteration of fast decoupled load flow is preformed to estimate post-contingent quantities (line flows, bus voltages) for other contingency cases. Based on system operators' past experience, each post-contingent quantity is assigned a degree of severity according to the potential damage that could be imposed on the power system by the quantity, should the contingency occurs. An approach based on fuzzy set theory is developed to deal with the imprecision of linguistic terms

  4. Guide to the declaration procedure and coding system for criteria concerning significant events related to safety, radiation protection or the environment, applicable to basic nuclear installations and the transport of radioactive materials

    International Nuclear Information System (INIS)

    Lacoste, Andre-Claude

    2005-01-01

    This guide notably contains various forms associated with the declaration of significant events, and explanations to fill them in: significant event declaration form for a basic nuclear installation, significant event declaration form for radioactive material transport, significant event report for a basic nuclear installation, significant event report for radioactive material transport, declaration criteria for significant events related to the safety of non-PWR basic nuclear installations, declaration criteria for significant events related to PWR safety, significant events declared further to events resulting in group 1 unavailability and non-compliance with technical operating specifications, declaration criteria for significant events concerning radiation protection for basic nuclear installations, declaration criteria for significant events concerning environmental protection, applicable to basic nuclear installations, and declaration criteria for significant events concerning radioactive material transport

  5. Information and communication. In the event of abnormal situations relating to nuclear power. Final report

    International Nuclear Information System (INIS)

    Carlsson, S.; Wuensche, G.

    1995-01-01

    As a consequence of the Chernobyl accident the need for better communication and cooperation between the countries of Nordic Europe (Denmark, Finland, Iceland, Norway and Sweden) in case of nuclear accidents became increasingly obvious. An initiative in this direction was taken by the Nordic Liaison Committee for Atomic Energy (NKA), a intergovernmental body responsible for cooperation in the Nuclear field, established by the Nordic Council. Thus, the Nordic Contact Forum became a reality. The Forum was created to serve as an informal network among nuclear experts, information officers and journalists in the Nordic countries. The network has been held together by a committee consisting of one representative from each country, as appointed by the Governments. The Nordic Contact Forum arranged the first of three seminars for representatives of public authorities, the nuclear industry, and journalists in 1988 in Vikersund, Norway. The Forum also has established a network among information officers for the exchange of information of public interest within the nuclear field. As a result of its work and agreement has been reached as to when and how this information is to be disseminated, and lists of contact points have been drawn up. This will make it easier to give the public in each of the Nordic countries better an, above all, better coordinated information. The existence of this network has had positive results. Thus, on several occasions false rumours of nuclear accidents, radioactive clouds, etc, have been neutralized before they have caused unnecessary public concern. (au)

  6. Radioactive particles after different nuclear events in the USSR (overview and modern data)

    Energy Technology Data Exchange (ETDEWEB)

    Gordeev, S.K.; Stukin, E.D.; Kvasnikova, E.V. [Institute of Global Climate and Ecology, Moscow (Russian Federation)

    2004-07-01

    Institute of Global Climate and Ecology participated in all stages of investigations concerning spreading of the radioactive particles formed after nuclear explosions. Since 1963 the radioactive particles from the surface nuclear explosions on the Semipalatinsk Test Site were investigated. Since 1964 the study of the environmental contamination from the underground nuclear explosions (including the cratering nuclear explosions) was carried out. Simultaneously the secondary radioactive aerosols released into the atmosphere from ventilated underground explosions were investigated. Since 1986 the forming and spreading of the radioactive aerosols from Chernobyl accident was studied. An overview of retrospective data will be presented. For example, the fragmentation radionuclides {sup 90}Sr, {sup 137}Cs and {sup 155}Eu, radionuclides induced by neutrons {sup 60}Co, {sup 152}Eu, {sup 154}Eu and transuranium radionuclides {sup 238}Pu, {sup 239+240}Pu and {sup 241}Am were estimated in 15 particles of August, 29, 1949 explosion using the semiconductor spectrometry and radiochemical analysis. Data collection include the samples taken on local traces of ground and underground excavation nuclear explosions, this information will be added by the modern data from soil samples near '1004' explosion (lake Chagan), October 2003. The results of comparison of radionuclide fractionation in the radioactive particles in slag from cratering nuclear explosions and in melt samples will be presented. Main results obtained under the IAEA Research Contract no. 11468. (author)

  7. A comparator-hypothesis account of biased contingency detection.

    Science.gov (United States)

    Vadillo, Miguel A; Barberia, Itxaso

    2018-02-12

    Our ability to detect statistical dependencies between different events in the environment is strongly biased by the number of coincidences between them. Even when there is no true covariation between a cue and an outcome, if the marginal probability of either of them is high, people tend to perceive some degree of statistical contingency between both events. The present paper explores the ability of the Comparator Hypothesis to explain the general pattern of results observed in this literature. Our simulations show that this model can account for the biasing effects of the marginal probabilities of cues and outcomes. Furthermore, the overall fit of the Comparator Hypothesis to a sample of experimental conditions from previous studies is comparable to that of the popular Rescorla-Wagner model. These results should encourage researchers to further explore and put to the test the predictions of the Comparator Hypothesis in the domain of biased contingency detection. Copyright © 2018 Elsevier B.V. All rights reserved.

  8. Identification of initiating events using a master logic diagram in low-power and shutdown PSA for nuclear power plant

    International Nuclear Information System (INIS)

    Han, S. J.; Park, J. H.; Kim, T. W.; Ha, J. J.

    2003-01-01

    It is necessary to apply a formal technique instead of an empirical technique in the identification of initiating events for Low Power and ShutDown (LPSD) Probabilistic Safety Assessment (PSA) of Nuclear Power Plant (NPP). The present study focuses on the examination of Master Logic Diagram (MLD) technique as a formal technique in the identification of initiating events. The MLD technique is a deductive tool using top-down approach for the formal and logical indentification of initiating events. The present study modified the MLD used in the full power PSA considering the characteristics of LPSD operation. The modified MLD introduced a systematic formation in decomposition process of which the MLD for full power PSA lacked. The modified MLD was able to identify initiating events systematic and logical. However, the formal techniques including the MLD have a limitation for precisely identifying all of the initiating events. In order to overcome this limitation, it is necessary to combine it with an empirical technique. We expect that the modified MLD can be used in an upgrade of the current LPSD PSAs

  9. Longitudinal decorrelation measures of flow magnitude and event-plane angles in ultrarelativistic nuclear collisions

    Science.gov (United States)

    BoŻek, Piotr; Broniowski, Wojciech

    2018-03-01

    We discuss the forward-backward correlations of harmonic flow in Pb +Pb collisions at the CERN Large Hadron Collider, applying standard multibin measures as well as new measures proposed here. We illustrate the methods with hydrodynamic model simulations based on event-by-event initial conditions from the wounded quark model with asymmetric rapidity emission profiles. Within the model, we examine independently the event-plane angle and the flow magnitude decorrelations. We find a specific hierarchy between various flow decorrelation measures and confirm certain factorization relations. We find qualitative agreement of the model and the data from the ATLAS and CMS Collaborations.

  10. Survey of special events recorded in nuclear power plants of the Federal Republic of Germany in the first quarter of 1991

    International Nuclear Information System (INIS)

    1991-01-01

    50 special events were reported in the old Federal States, 47 of them belonged to the reporting category N (normal notification), three to the reporting category E (immediate notification). According to the international evluation scale (INES = International Nuclear Events Scale) five of those events fell under INES category 1, the rest under category 0. The Greifswald nuclear power plant reported three events of category AE-3 (lowest category) at KGR-5. There was no release of radioactivity involved in these incidents, and there were no effects on man or the environment reported. (HP) [de

  11. Development of a software for predicting the effects of nuclear and radiological terrorism events in city areas

    International Nuclear Information System (INIS)

    Luo Lijuan; Chen Bo; Zhuo Weihai; Lu Shuyu

    2011-01-01

    Objective: To develop a new software system that can directly display the predicted results on an electronic map, in order to get a directly perceived understanding of the affected areas of nuclear and radiological terrorism events in city areas. Methods: Three scenarios of events including spreading radioactive materials, dirty bomb attack, and explosion or arson attacks on the radiation facilities were assumed. Gaussian diffusion model was employed to predict the spread and deposition of radioactive pollutants, and both the internal and external doses were estimated for the representative person by using the corresponding dose conversion factors. Through integration of the computing system and Mapinfo geographic information system (GIS), the predicted results were visually displayed on the electronic maps of a city. Results: The new software system could visually display the predicted results on the electronic map of a city, and the predicted results were consistent with those calculated by the similar software Hotspot®. The deviation between this system and Hotspot was less than 0.2 km for predicted isoplethic curves of dose rate downwind. Conclusions: The newly developed software system is of the practical value in predicting the effects of nuclear and radiological terrorism events in city areas. (authors)

  12. Contingent factors affecting network learning

    OpenAIRE

    Peters, Linda D.; Pressey, Andrew D.; Johnston, Wesley J.

    2016-01-01

    To increase understanding of the impact of individuals on organizational learning processes, this paper explores the impact of individual cognition and action on the absorptive capacity process of the wider network. In particular this study shows how contingent factors such as social integration mechanisms and power relationships influence how network members engage in, and benefit from, learning. The use of cognitive consistency and sensemaking theory enables examination of how these conting...

  13. IPEEE review of external events of the Asco I nuclear plant

    International Nuclear Information System (INIS)

    Aleman, A.; Canadell, F.; Beltran, F.; Pifarre, D.; Hernandez, H.; Gasca, C.

    2012-01-01

    During the risk analysis update of Asco NPP (2010), it has been carried out a review of the vulnerabilities against severe accidents caused by external events (individual Plant Examination of external Events, IPEEE). The assessment has includent analysis of accidents in industrial and military facilities nearby and transportation accidents (i.e., rail, road and aircraft impact) release of hazardous materials on site, external flooding, turbine missiles and strong winds. (Author)

  14. Multifragmentation of a very heavy nuclear system (I): selection of single-source events

    Energy Technology Data Exchange (ETDEWEB)

    Frankland, J.D.; Bacri, Ch.O.; Borderie, B. [Paris-11 Univ., Inst. de Physique Nucleaire, 91 - Orsay (France)] [and others

    2000-07-01

    A sample of 'single-source' events, compatible with the multifragmentation of very heavy fused systems, are isolated among well-measured {sup 155}Gd + {sup nat}U 36 A.MeV reactions by examining the evolution of the kinematics of fragments with Z {>=} 5 as a function of the dissipated energy and loss of memory of the entrance channel. Single-source events are found to be the result of very central collisions. Such central collisions may also lead to multiple fragment emission due to the decay of excited projectile- and target-like nuclei and so-called 'neck' emission, and for this reason the isolation of single-source events is very difficult. Event-selection criteria based on centrality of collisions, or on the isotropy of the emitted fragments in each event, are found to be inefficient to separate the two mechanisms, unless they take into account the redistribution of fragments' kinetic energies into directions perpendicular to the beam axis. The selected events are good candidates to look for bulk effects in the multifragmentation process. (authors)

  15. Multifragmentation of a very heavy nuclear system (I): selection of single-source events

    International Nuclear Information System (INIS)

    Frankland, J.D.; Bacri, Ch.O.; Borderie, B.; Rivet, M.F.; Squalli, M.; Auger, G.; Bellaize, N.; Bocage, F.; Bougault, R.; Brou, R.; Buchet, Ph.; Chbihi, A.; Colin, J.; Cussol, D.; Dayras, R.; Demeyer, A.; Dore, D.; Durand, D.; Galichet, E.; Genouin-Duhamel, E.; Gerlic, E.; Guinet, D.; Lautesse, Ph.; Laville, J.L.; Lecolley, J.F.; Legrain, R.; Le Neindre, N.; Lopez, O.; Louvel, M.; Maskay, A.M.; Nalpas, L.; Nguyen, A.D.; Parlog, M.; Peter, J.; Plagnol, E.; Rosato, E.; Saint-Laurent, F.; Salou, S.; Steckmeyer, J.C.; Stern, M.; Tabacaru, G.; Tamain, B.; Tirel, O.; Tassan-Got, L.; Vient, E.; Volant, C.; Wieleczko, J.P.

    2001-01-01

    A sample of 'single-source' events, compatible with the multifragmentation of very heavy fused systems, are isolated among well-measured 155 Gd+ nat U 36 A MeV reactions by examining the evolution of the kinematics of fragments with Z≥5 as a function of the dissipated energy and loss of memory of the entrance channel. Single-source events are found to be the result of very central collisions. Such central collisions may also lead to multiple fragment emission due to the decay of excited projectile- and target-like nuclei and so-called 'neck' emission, and for this reason the isolation of single-source events is very difficult. Event-selection criteria based on centrality of collisions, or on the isotropy of the emitted fragments in each event, are found to be inefficient to separate the two mechanisms, unless they take into account the redistribution of fragments' kinetic energies into directions perpendicular to the beam axis. The selected events are good candidates to look for bulk effects in the multifragmentation process

  16. Relaxation near Supermassive Black Holes Driven by Nuclear Spiral Arms: Anisotropic Hypervelocity Stars, S-stars, and Tidal Disruption Events

    Energy Technology Data Exchange (ETDEWEB)

    Hamers, Adrian S. [Institute for Advanced Study, School of Natural Sciences, Einstein Drive, Princeton, NJ 08540 (United States); Perets, Hagai B., E-mail: hamers@ias.edu [Technion—Israel Institute of Technology, Haifa 32000 (Israel)

    2017-09-10

    Nuclear spiral arms are small-scale transient spiral structures found in the centers of galaxies. Similarly to their galactic-scale counterparts, nuclear spiral arms can perturb the orbits of stars. In the case of the Galactic center (GC), these perturbations can affect the orbits of stars and binaries in a region extending to several hundred parsecs around the supermassive black hole (SMBH), causing diffusion in orbital energy and angular momentum. This diffusion process can drive stars and binaries to close approaches with the SMBH, disrupting single stars in tidal disruption events (TDEs), or disrupting binaries, leaving a star tightly bound to the SMBH and an unbound star escaping the galaxy, i.e., a hypervelocity star (HVS). Here, we consider diffusion by nuclear spiral arms in galactic nuclei, specifically the Milky Way GC. We determine nuclear-spiral-arm-driven diffusion rates using test-particle integrations and compute disruption rates. Our TDE rates are up to 20% higher compared to relaxation by single stars. For binaries, the enhancement is up to a factor of ∼100, and our rates are comparable to the observed numbers of HVSs and S-stars. Our scenario is complementary to relaxation driven by massive perturbers. In addition, our rates depend on the inclination of the binary with respect to the Galactic plane. Therefore, our scenario provides a novel potential source for the observed anisotropic distribution of HVSs. Nuclear spiral arms may also be important for accelerating the coalescence of binary SMBHs and for supplying nuclear star clusters with stars and gas.

  17. Glimpsing over the event horizon: evolution of nuclear pores and envelope.

    Science.gov (United States)

    Jékely, Gáspár

    2005-02-01

    The origin of eukaryotes from prokaryotic ancestors is one of the major evolutionary transitions in the history of life. The nucleus, a membrane bound compartment for confining the genome, is a central feature of eukaryotic cells and its origin also has to be a central feature of any workable theory that ventures to explain eukaryotic origins. Recent bioinformatic analyses of components of the nuclear pore complex (NPC), the nuclear envelope (NE), and the nuclear transport systems revealed exciting evolutionary connections (e.g., between NPC and coated vesicles) and provided a useful record of the phyletic distribution and history of NPC and NE components. These analyses allow us to refine theories on the origin and evolution of the nucleus, and consequently, of the eukaryotic cell.

  18. Assessment of the safety of Ulchin nuclear power plant in the event of tsunami using parametric study

    International Nuclear Information System (INIS)

    Kim, Ji Young; Kang, Keum Seok

    2011-01-01

    Previous evaluations of the safety of the Ulchin Nuclear Power Plant in the event of a tsunami have the shortcoming of uncertainty of the tsunami sources. To address this uncertainty, maximum and minimum wave heights at the intake of Ulchin NPP have been estimated through a parametric study, and then assessment of the safety margin for the intake has been carried out. From the simulation results for the Ulchin NPP site, it can be seen that the coefficient of eddy viscosity considerably affects wave height at the inside of the breakwater. In addition, assessment of the safety margin shows that almost all of the intake water pumps have a safety margin over 2 m, and Ulchin NPP site seems to be safe in the event of a tsunami according to this parametric study, although parts of the CWPs rarely have a margin for the minimum wave height

  19. A new scanning system for alpha decay events as calibration sources for range-energy relation in nuclear emulsion

    Science.gov (United States)

    Yoshida, J.; Kinbara, S.; Mishina, A.; Nakazawa, K.; Soe, M. K.; Theint, A. M. M.; Tint, K. T.

    2017-03-01

    A new scanning system named "Vertex picker" has been developed to rapid collect alpha decay events, which are calibration sources for the range-energy relation in nuclear emulsion. A computer-controlled optical microscope scans emulsion layers exhaustively, and a high-speed and high-resolution camera takes their micrographs. A dedicated image processing picks out vertex-like shapes. Practical operations of alpha decay search were demonstrated by emulsion sheets of the KEK-PS E373 experiment. Alpha decays of nearly 28 events were detected in eye-check work on a PC monitor per hour. This yield is nearly 20 times more effective than that by the conventional eye-scan method. The speed and quality is acceptable for the coming new experiment, J-PARC E07.

  20. A new scanning system for alpha decay events as calibration sources for range-energy relation in nuclear emulsion

    International Nuclear Information System (INIS)

    Yoshida, J.; Kinbara, S.; Mishina, A.; Nakazawa, K.; Soe, M.K.; Theint, A.M.M.; Tint, K.T.

    2017-01-01

    A new scanning system named “Vertex picker” has been developed to rapid collect alpha decay events, which are calibration sources for the range-energy relation in nuclear emulsion. A computer-controlled optical microscope scans emulsion layers exhaustively, and a high-speed and high-resolution camera takes their micrographs. A dedicated image processing picks out vertex-like shapes. Practical operations of alpha decay search were demonstrated by emulsion sheets of the KEK-PS E373 experiment. Alpha decays of nearly 28 events were detected in eye-check work on a PC monitor per hour. This yield is nearly 20 times more effective than that by the conventional eye-scan method. The speed and quality is acceptable for the coming new experiment, J-PARC E07.

  1. Assessment of nuclear medicine capabilities in responding to a radiological terrorism event. Technical memorandum

    Energy Technology Data Exchange (ETDEWEB)

    Stodilka, R.Z. [Univ. of Western Ontario, Schulich School of Medicine, London, Ontario (Canada); Wilkinson, D

    2006-09-15

    Substantial effort has been placed into enhancing federal capabilities for responding to a Chemical, Biological, Radiological, or Nuclear (CBRN) terrorist attack. However, little emphasis has been placed on including the local-level medical responders in these efforts. In effecting response to a radiological incident, potentially useful resources to access are health care professionals with training in matters of ionizing radiation, namely: nuclear medicine physicians, radiologists, radiation oncologists, medical physicists, and technologists. In this report, we focus on Nuclear Medicine expertise in Canada, and place this expertise into the context of assisting with a radiological terrorist incident. Nuclear Medicine expertise, along with its supporting infrastructure has already been deployed in proportion to the distribution of the civilian population. Given the expectations that the civilian population places in these health care professionals, their immediate access to specialized equipment, and the delay between a radiological terrorist incident and the arrival of federal expert capabilities, it is likely that these health care professionals will play important roles in emergency response. These roles will likely be: identifying the nature of the incident, triage, decontamination, coordinating with First Responders, and communicating with the media. Acknowledging the potential value of these professionals in responding to a radiological terrorist incident, steps should be taken to enlist their support and integrate them into a coherent national strategy. (author)

  2. Assessment of nuclear medicine capabilities in responding to a radiological terrorism event. Technical memorandum

    International Nuclear Information System (INIS)

    Stodilka, R.Z.; Wilkinson, D.

    2006-09-01

    Substantial effort has been placed into enhancing federal capabilities for responding to a Chemical, Biological, Radiological, or Nuclear (CBRN) terrorist attack. However, little emphasis has been placed on including the local-level medical responders in these efforts. In effecting response to a radiological incident, potentially useful resources to access are health care professionals with training in matters of ionizing radiation, namely: nuclear medicine physicians, radiologists, radiation oncologists, medical physicists, and technologists. In this report, we focus on Nuclear Medicine expertise in Canada, and place this expertise into the context of assisting with a radiological terrorist incident. Nuclear Medicine expertise, along with its supporting infrastructure has already been deployed in proportion to the distribution of the civilian population. Given the expectations that the civilian population places in these health care professionals, their immediate access to specialized equipment, and the delay between a radiological terrorist incident and the arrival of federal expert capabilities, it is likely that these health care professionals will play important roles in emergency response. These roles will likely be: identifying the nature of the incident, triage, decontamination, coordinating with First Responders, and communicating with the media. Acknowledging the potential value of these professionals in responding to a radiological terrorist incident, steps should be taken to enlist their support and integrate them into a coherent national strategy. (author)

  3. Side Event at 55th IAEA General Conference: Nuclear Industry Cooperation. Presentations

    International Nuclear Information System (INIS)

    2011-01-01

    The main objective of this high level meeting is to identify and share recent experience, relevant factors and approaches influencing safety and performance improvements, as well as long-term strategies of the nuclear industry, taking into consideration the Fukushima accident to the extent

  4. An investigation on unintended reactor trip events in terms of human error hazards of Korean nuclear power plants

    International Nuclear Information System (INIS)

    Kim, Sa Kil; Lee, Yong Hee; Jang, Tong Il; Oh, Yeon Ju; Shin, Kwang Hyeon

    2014-01-01

    Highlights: • A methodology to identify human error hazards has been established. • The proposed methodology is a preventive approach to identify not only human error causes but also its hazards. • Using the HFACS framework we tried to find out not causations but all of the hazards and relationships among them. • We determined countermeasures against human errors through dealing with latent factors such as organizational influences. - Abstract: A new approach for finding the hazards of human errors, and not just their causes, in the nuclear industry is currently required. This is because finding causes of human errors is really impossible owing to the multiplicity of causes in each case. Thus, this study aims at identifying the relationships among human error hazards and determining the strategies for preventing human error events by means of a reanalysis of the reactor trip events in Korea NPPs. We investigated human errors to find latent factors such as decisions and conditions in all of the unintended reactor trip events during the last dozen years. In this study, we applied the HFACS (Human Factors Analysis and Classification System), which is a commonly utilized tool for investigating human contributions to aviation accidents under a widespread evaluation scheme. Using the HFACS framework, we tried to find out not the causations but all of the hazards and their relationships in terms of organizational factors. Through the trial, we proposed not only meaningful frequencies of each hazards also correlations of them. Also, considering the correlations of each hazards, we suggested useful strategies to prevent human error event. A method to investigate unintended nuclear reactor trips by human errors and the results will be discussed in more detail

  5. Extensive Analysis of Worldwide Events Related to The Construction and Commissioning of Nuclear Power Plants: Lessons Learned and Recommendations

    International Nuclear Information System (INIS)

    Noel, M.; Zerger, B.; Vuorio, U.; )

    2011-01-01

    Lessons learnt from past experience are extensively used to improve the safety of nuclear power plants (NPPs) worldwide. Although the process of analyzing operational experience is now widespread and well developed, the need for establishment of a similar process for construction experience was highlighted by several countries embarking on construction of new NPPs and in some international forums including the Working Group on the Regulation of New Reactors (WGRNR) of the OECD-NEA. In 2008, EU Member State Safety Authorities participating to the EU Clearinghouse on Operational Experience Feedback decided to launch a topical study on events related to pre-operational stages of NPPs. The aim of this topical study is to reduce the recurrence of events related to the construction, the initial component manufacturing and the commissioning of NPPs, by identifying the main recurring and safety significant issues. For this study, 1090 IRS event reports, 857 US Licensee Event Reports (LERs) and approximately 100 WGRNR reports have been preselected based on key word searches and screened. The screening period starts from the beginning of the databases operation (in the 1980's as far as IRS and LER database are concerned) and ends in November 2009. After this initial screening, a total of 582 reports have been found applicable (247 IRS reports, 309 LERs and 26 WGRNR reports). Events considered for this study were those which have been initiated before the start of commercial operation, and detected before or even long after commercial operation. The events have been classified into 3 main categories (construction, manufacturing and commissioning), and into further sub-categories (building structures, metallic liners, electrical components, anchors, I and C, penetrations and building seals, emergency diesel generators, pipes, valves, welds, pumps, etc.) in order to facilitate the detailed analysis with the final objective to formulate both equipment specific

  6. Notifiable events in systems for fission of nuclear fuels - nuclear power plants and research reactors with maximum output exceeding 50 kW of thermal normal rating - in the Federal Republic of Germany. Quarterly report, 2nd quarter of 1996

    International Nuclear Information System (INIS)

    1996-01-01

    There were 32 notifiable events in nuclear power plants in Germany in the second quarter of 1996. The report lists and characterises all the 32 events notified in the reporting period. The events did not involve any radioactivity release exceeding the maximum permissible limits during this period, so that there were no radiation hazards to the population or the environment. One event was classified at level 1 of the INES event scale (Anomaly). Research reactor operators in Germany reported 5 notifiable events in the reporting period. The report lists and characterises these events. These events did not involve any radioactivity release exceeding the maximum permissible limits during this period, so that there were no radiation hazards to the population or the environment. All events notified were classified into the lowest categories of safety significance of the official event scales (N, or below scale). (orig./DG) [de

  7. Network location theory and contingency planning

    Energy Technology Data Exchange (ETDEWEB)

    Hakimi, S L

    1983-08-01

    A brief survey of results in network location theory is first presented. Then, a systems view of contingency planning is described. Finally, some results in location theory are re-examined and it is shown that they are motivated by contingency planning considerations. Some new issues and problems in location theory are described, which, if properly tackled, will have a substantial impact on contingency planning in transportation.

  8. An Extreme Meteorological Events Analysis For Nuclear Power Plant (NPP) Siting Project at Bangka Island, Indonesia

    Science.gov (United States)

    Septiadi, Deni; S, Yarianto Sugeng B.; Sriyana; Anzhar, Kurnia; Suntoko, Hadi

    2018-03-01

    The potential sources of meteorological phenomena in Nuclear Power Plant (NPP) area of interest are identified and the extreme values of the possible resulting hazards associated which such phenomena are evaluated to derive the appropriate design bases for the NPP. The appropriate design bases shall be determined according to the Nuclear Energy Regulatory Agency (Bapeten) applicable regulations, which presently do not indicate quantitative criteria for purposes of determining the design bases for meteorological hazards. These meteorological investigations are also carried out to evaluate the regional and site specific meteorological parameters which affect the transport and dispersion of radioactive effluents on the environment of the region around the NPP site. The meteorological hazards are to be monitored and assessed periodically over the lifetime of the plant to ensure that consistency with the design assumptions is maintained throughout the full lifetime of the facility.

  9. Generic implications of ATWS events at the Salem Nuclear Power Plant. Licensee and staff actions

    International Nuclear Information System (INIS)

    1983-08-01

    This report, Volume 2 of two volumes of NUREG-1000, describes the intermediate term actions to be taken by licensees and applicants of the US Nuclear Regulatory Commission (NRC), on the one hand, and by NRC staff, on the other, to address the generic issues raised by two anticipated transients without scram (ATWS) at the Salem Nuclear Generating Station, Unit 1, on February 22 and 25, 1983. These actions came about as a result of the findings of NUREG-1000, Volume 1, and of reviews by the NRC Committee to Review Generic Requirements, the NRC Program Offices, and the Commission. The actions to be taken by licensees and applicants have been detailed in a letter pursuant to 10 CFR 50.54(f)

  10. Attenuation of the contingency detection effect in the extrastriate body area in autism spectrum disorder.

    Science.gov (United States)

    Okamoto, Yuko; Kitada, Ryo; Tanabe, Hiroki C; Hayashi, Masamichi J; Kochiyama, Takanori; Munesue, Toshio; Ishitobi, Makoto; Saito, Daisuke N; Yanaka, Hisakazu T; Omori, Masao; Wada, Yuji; Okazawa, Hidehiko; Sasaki, Akihiro T; Morita, Tomoyo; Itakura, Shoji; Kosaka, Hirotaka; Sadato, Norihiro

    2014-10-01

    Detection of the contingency between one's own behavior and consequent social events is important for normal social development, and impaired contingency detection may be a cause of autism spectrum disorder (ASD). To depict the neural underpinnings of this contingency effect, 19 adults with ASD and 22 control participants underwent functional MRI while imitating another's actions and their actions being imitated by the other. As the extrastriate body area (EBA) receives efference copies of one's own movements, we predicted that the EBA would show an atypical response during contingency detection in ASD. We manipulated two factors: the congruency of the executed and observed actions, and the order of action execution and observation. Both groups showed the congruency effect in the bilateral EBA during imitation. When action preceded observation, the left EBA of the control group showed the congruency effect, representing the response to being imitated, indicating contingency detection. The ASD group showed a reduced contingency effect in the left EBA. These results indicate that the function of the EBA in the contingency detection is altered in ASD. Copyright © 2014 Elsevier Ireland Ltd and the Japan Neuroscience Society. All rights reserved.

  11. The accident of the Fukushima-Daiichi nuclear plant. Status two years after the event

    International Nuclear Information System (INIS)

    2013-03-01

    In a first part, this report briefly recalls the circumstances and occurrence of the accident, gives an overview of actions undertaken by the IRSN (calculations of installation damages, modelling of contaminated air movements, simulations of radionuclide dispersion in the sea environment, information of French nationals in Japan, press and public information), and an overview of strength tests of nuclear installations (additional safety assessments and European stress tests). The second part gives an overview of the situation in Japan two years after the accident: evolution of governance in terms of nuclear risk management, condition of the Fukushima plant in January 2013, health and environmental impact and post-accidental management, actions undertaken by the IRSN (assessment of doses potentially received by populations, strengthening of cooperation between Japan and France in the field of severe accidents, participation to the Fukushima Dialogue). The third part presents the contribution of the IRSN to the strengthening of nuclear safety and radiation protection at the international level, at the European level, and in France

  12. Integrated safety assessment of Indian nuclear power plants for extreme events: reducing impact on public mind

    International Nuclear Information System (INIS)

    Kakodkar, Anil; Singh, Ram Kumar

    2013-01-01

    Nuclear energy professionals need to understand and address the catastrophe syndrome that of late seems to be increasingly at work in public mind in the context of nuclear energy. Classically the nuclear power reactor design and system evolution has been based on the logic of minimization of risk to an acceptable level and its quantification based on a deterministic approach and backed up by a further assessment based on the probabilistic methodology. However, in spite of minimization of risk, the reasons for anxiety and trauma in public mind that still prevails in the context of severe accidents needs to be understood and addressed. Margins between maximum credible accidents factored in the design and the ultimate load withstanding capacities of relevant systems need to be enhanced and guaranteed with a view to minimize release of radioactivity and avoid serious impact in public domain. A more realistic basis for management of an accident in public domain also needs to be quantified for this purpose. Assurance to public on limiting the consequences to a level that does not lead to a trauma is something that we need to be able to credibly demonstrate and confirm. The findings from Chernobyl reports point to significant psychological effects and related health disorders due to large scale emergency relocation of people that could have been possibly reduced by an order of magnitude without significant additional safety detriment

  13. Phosphorylation and nuclear accumulation are distinct events contributing to the activation of p53

    International Nuclear Information System (INIS)

    O'Hagan, Heather M.; Ljungman, Mats

    2004-01-01

    It has been recently shown that ionizing radiation (IR) and the mRNA synthesis inhibitor 5,6-dichloro-1-b-D-ribofuranosylbenzimidazole (DRB) act in synergy to induce p53-mediated transactivation of reporter plasmids in human cells [Oncogene 19 (2000) 3829]. We have extended these studies and show that ionizing radiation and DRB also act in synergy to induce ATM-mediated phosphorylation of the ser15 site of p53 and enhance the expression of endogenous p21 protein. Examination of the localization of p53 revealed that while DRB did not induce phosphorylation of the ser15 site of p53 but efficiently accumulated p53 in the nucleus, ionizing radiation induced phosphorylation of the ser15 site of p53 without prolonged nuclear accumulation. Importantly, the combination of DRB and IR resulted in a strong accumulation of phosphorylated p53 in the nucleus that was more persistent then p53 accumulation after IR alone. Furthermore, the nuclear export inhibitor leptomycin B showed a similar synergy with IR as did DRB regarding ser15 phosphorylation of p53 and p21 induction. These results suggest that the synergistic activation of the p53 response by the combination treatment is due to the activation of two distinct pathways where DRB causes the prolonged nuclear accumulation of p53 while ionizing radiation activates p53 by ATM-mediated phosphorylation

  14. Caspase-dependant activation of chymotrypsin-like proteases mediates nuclear events during Jurkat T cell apoptosis

    International Nuclear Information System (INIS)

    O'Connell, A.R.; Lee, B.W.; Stenson-Cox, C.

    2006-01-01

    Apoptosis involves a cascade of biochemical and morphological changes resulting in the systematic disintegration of the cell. Caspases are central mediators of this process. Supporting and primary roles for serine proteases as pro-apoptotic mediators have also been highlighted. Evidence for such roles comes largely from the use of pharmacological inhibitors; as a consequence information regarding their apoptotic function and biochemical properties has been limited. Here, we circumvented limitations associated with traditional serine protease inhibitors through use of a fluorescently labelled inhibitor of serine proteases (FLISP) that allowed for analysis of the specificity, regulation and positioning of apoptotic serine proteases within a classical apoptotic cascade. We demonstrate that staurosporine triggers a caspase-dependant induction of chymotrypsin-like activity in the nucleus of apoptotic Jurkat T cells. We show that serine protease activity is required for the generation of late stage nuclear events including condensation, fragmentation and DNA degradation. Furthermore, we reveal caspase-dependant activation of two chymotrypsin-like protein species that we hypothesize mediate cell death-associated nuclear events

  15. Development and application of a methodology for the analysis of significant human related event trends in nuclear power plants

    International Nuclear Information System (INIS)

    Cho, H.Y.

    1981-01-01

    A methodology is developed to identify and flag significant trends related to the safety and availability of U.S. commercial nuclear power plants. The development is intended to aid in reducing likelihood of human errors. To assure that the methodology can be easily adapted to various types of classification schemes of operation data, a data bank classified by the Transient Analysis Classification and Evaluation (TRACE) scheme is selected for the methodology. The significance criteria for human-initiated events affecting the systems and for events caused by human deficiencies were developed. Clustering analysis was used to verify the learning trend in multidimensional histograms. A computer code is developed based on the K-Means algorithm and applied to find the learning period in which error rates are monotonously decreasing with plant age. The Freeman-Tukey (F-T) deviates are used to select generic problems identified by a large positive value (here approximately over 2.0) for the deviate. The identified generic problems are: decision errors which are highly associated with reactor startup operations in the learning period of PWR plants (PWRs), response errors which are highly associated with Secondary Non-Nuclear Systems (SNS) in PWRs, and significant errors affecting systems and which are caused by response action are highly associated with startup reactor mode in BWRS

  16. 40 CFR 264.53 - Copies of contingency plan.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 25 2010-07-01 2010-07-01 false Copies of contingency plan. 264.53... Contingency Plan and Emergency Procedures § 264.53 Copies of contingency plan. A copy of the contingency plan... called upon to provide emergency services. [Comment: The contingency plan must be submitted to the...

  17. Pavlovian contingencies and temporal information.

    Science.gov (United States)

    Balsam, Peter D; Fairhurst, Stephen; Gallistel, Charles R

    2006-07-01

    The effects of altering the contingency between the conditioned stimulus (CS) and the unconditioned stimulus (US) on the acquisition of autoshaped responding was investigated by changing the frequency of unsignaled USs during the intertrial interval. The addition of the unsignaled USs had an effect on acquisition speed comparable with that of massing trials. The effects of these manipulations can be understood in terms of their effect on the amount of information (number of bits) that the average CS conveys to the subject about the timing of the next US. The number of reinforced CSs prior to acquisition is inversely related to the information content of the CS.

  18. Trend analysis and comparison of operators' human error events occurred at overseas and domestic nuclear power plants

    International Nuclear Information System (INIS)

    Takagawa, Kenichi

    2006-01-01

    Human errors by operators at overseas and domestic nuclear power plants during the period from 2002 to 2005 were compared and their trends analyzed. The most frequently cited cause of such errors was 'insufficient team monitoring' (inadequate superiors' and other crews' instructions and supervision) both at overseas and domestic plants, followed by 'insufficient self-checking' (lack of cautions by the operator himself). A comparison of the effects of the errors on the operations of plants in Japan and the United Sates showed that the drop in plant output and plant shutdowns at plants in Japan were approximately one-tenth of those in the United States. The ratio of automatic reactor trips to the total number of human errors reported is about 6% for both Japanese and American plants. Looking at changes in the incidence of human errors by years of occurrence, although a distinctive trend cannot be identified for domestic nuclear power plants due to insufficient reported cases, 'inadequate self-checking' as a factor contributing to human errors at overseas nuclear power plants has decreased significantly over the past four years. Regarding changes in the effects of human errors on the operations of plants during the four-year period, events leading to an automatic reactor trip have tended to increase at American plants. Conceivable factors behind this increasing tendency included lack of operating experience by a team (e.g., plant transients and reactor shutdowns and startups) and excessive dependence on training simulators. (author)

  19. CNE (Embalse nuclear power plant): probabilistic safety study. Electric power supply. Events sequence

    International Nuclear Information System (INIS)

    Figueroa, N.

    1987-01-01

    The plant response to the occurrence of the starting event 'total loss of electric power supply to class IV and class III' is analyzed. This involves the study of automatical actions of safety and process systems as well as the operator actions. The probabilistic evaluation of starting event frequency is performed through fault-tree techniques. The frequency of occurrence 'loss of electric power supply to class IV (λIV = 0.56/year) and the probability of failure to demand of 'reserve' generating groups (Pd III 6.79 x 10 -3 ) contribute to the mentioned frequency. As soon as the starting event occurs, the reactor power must be reduced to 0%, the fuel must be cooled through the thermo siphon and decay heat has to be removed. The events sequence analysis leads to the conclusion that the non shutting down of the reactor with any of the shutdown systems is 'incredible' (10 -6 /year). In all cases the fuel is cooled by building the thermo siphon except when a substantial inventory loss exist due to a closure failure of some valve of pressure and inventory control system. The order of magnitude of the failure of decay heat removal through the steam generators is 4 x 10 -4 . This removal would be assured by the emergency water system. Therefore, the frequency of the sequence of possible core meltdown, when the reactor does not shut down is: λ = 5 x 10 -9 /year and for the failure of heat removal: λ = 2 x 10 -6 /year. (Author)

  20. Skin substitutes for management of thermal burns in the event of a nuclear detonation

    International Nuclear Information System (INIS)

    Singh, Rita

    2014-01-01

    Skin substitutes can play a potential role in the treatment of burn injuries in a nuclear scenario. Defence Laboratory, Jodhpur is involved in the development of various types of skin substitutes for use in burn injuries. Amniotic membranes collected from placentae are processed as biological dressings and sterilized by gamma radiation. Multi-centric clinical trials have demonstrated the functional and clinical efficacy of radiation sterilized biological dressings in burn wound care. Chitin-nanosilver membranes and hydrogels have also been developed and characterized for use as burn wound dressing

  1. Safety philosophy and design principles for systems and components of nuclear power plant: external event

    International Nuclear Information System (INIS)

    Lopes, J.P.G.

    1986-01-01

    In nuclear power plants, some systems and components are designed to withstand external impacts. Such systems and components are those which have to perform their functions even during and after the occurrences of an earthquake, for example, fulfilling the safety objectives and avoiding the release of radioactive material to the environment. The aim of this report is to introduce the safety philosophy and design principles for systems/components to perform their functions during and after the occurrence of an earthquake, as applied by NUCLEN for Angra 2 and 3. (Author) [pt

  2. The critical dimensions of the response-reinforcer contingency.

    Science.gov (United States)

    Williams, B A.

    2001-05-03

    Two major dimensions of any contingency of reinforcement are the temporal relation between a response and its reinforcer, and the relative frequency of the reinforcer given the response versus when the response has not occurred. Previous data demonstrate that time, per se, is not sufficient to explain the effects of delay-of-reinforcement procedures; needed in addition is some account of the events occurring in the delay interval. Moreover, the effects of the same absolute time values vary greatly across situations, such that any notion of a standard delay-of-reinforcement gradient is simplistic. The effects of reinforcers occurring in the absence of a response depend critically upon the stimulus conditions paired with those reinforcers, in much the same manner as has been shown with Pavlovian contingency effects. However, it is unclear whether the underlying basis of such effects is response competition or changes in the calculus of causation.

  3. Nonlinear Methodologies for Identifying Seismic Event and Nuclear Explosion Using Random Forest, Support Vector Machine, and Naive Bayes Classification

    Directory of Open Access Journals (Sweden)

    Longjun Dong

    2014-01-01

    Full Text Available The discrimination of seismic event and nuclear explosion is a complex and nonlinear system. The nonlinear methodologies including Random Forests (RF, Support Vector Machines (SVM, and Naïve Bayes Classifier (NBC were applied to discriminant seismic events. Twenty earthquakes and twenty-seven explosions with nine ratios of the energies contained within predetermined “velocity windows” and calculated distance are used in discriminators. Based on the one out cross-validation, ROC curve, calculated accuracy of training and test samples, and discriminating performances of RF, SVM, and NBC were discussed and compared. The result of RF method clearly shows the best predictive power with a maximum area of 0.975 under the ROC among RF, SVM, and NBC. The discriminant accuracies of RF, SVM, and NBC for test samples are 92.86%, 85.71%, and 92.86%, respectively. It has been demonstrated that the presented RF model can not only identify seismic event automatically with high accuracy, but also can sort the discriminant indicators according to calculated values of weights.

  4. CNE (Embalse nuclear power plant): probabilistic safety study. Loss of service water. Probabilistic evaluation and analysis through events sequence

    International Nuclear Information System (INIS)

    Couto, A.J.; Perez, S.S.

    1987-01-01

    This work is part of a study on the service water systems of the Embalse nuclear power plant from a safety point of view. The faults of service water systems of high and low pressure that can lead to situations threatening the plant safety were analyzed in a previous report. The event 'total loss of low pressure service water' causes the largest number of such conditions. Such event is an operational incident that can lead to an accident situation due to faults in the required process systems or by omission of a procedure. The annual frequency of the event 'total loss of low pressure service water' is calculated. The main contribution comes from pump failure. The evaluation of the accident sequences shows that the most direct way to the liberation of fission products is the loss of steam generators as heat sink. The contributions to small and large LOCA and electric supply loss are analyzed. The sequence that leads to tritium release through boiling of moderator is also evaluated. (Author)

  5. Safety at civil basic nuclear installations other than nuclear power plants in France. Lessons learned by IRSN from significant events reported in 2013 and 2014

    International Nuclear Information System (INIS)

    2016-01-01

    IRSN publishes the lessons learned from its analysis of significant events which have occurred in 2013 and 2014 at 82 civil basic nuclear installations (INBs) other than nuclear power plants (NPPs). Produced every two year since 2009, this report concerns 73 facilities such as plants, laboratories, facilities for the treatment, disposal and storage of waste, and facilities which have been decommissioned, and 9 research reactors, operated by around twenty different licensees in France. 210 and 227 significant events were respectively reported in 2013 and 2014 to the French Nuclear Safety Authority (ASN). This number remains similar to previous years and tends to 'stabilize' at around 200 to 220. On the one hand, among the improvements observed in 2013 and 2014, IRSN found two subjects of particular interest: - Efforts made by the licensees to increase reliability of organisational and human measures related to handling operations, in particular at the spent fuel reprocessing plant of AREVA NC La Hague and in the radioactive waste storage facilities operated by the CEA. - Important improvement program deployed by the licensee of the FBFC plant in Romans-sur-Isere (Drome) to enhance operating practices, particularly regarding management of criticality risks (prevention of uncontrolled chain reactions). On the other hand, three subjects still require special vigilance by licensees: - Ensuring full control over the safety documentation of facilities. IRSN's cross-cutting analysis of events reveal a large number of cases for which parts of the safety documentation are not fully understood at the facilities, are not applied, are inaccurate or not applicable to the situation. - Ensuring in-depth and comprehensive planning of installation clean-up and dismantling operations. Risks of worker exposure to ionising radiation are higher during these operations which may require personnel to work in close proximity to radioactive materials. - Ensuring more

  6. Contingent Diversity on Anthropic Landscapes

    Directory of Open Access Journals (Sweden)

    William Balée

    2010-02-01

    Full Text Available Behaviorally modern human beings have lived in Amazonia for thousands of years. Significant dynamics in species turnovers due to human-mediated disturbance were associated with the ultimate emergence and expansion of agrarian technologies in prehistory. Such disturbances initiated primary and secondary landscape transformations in various locales of the Amazon region. Diversity in these locales can be understood by accepting the initial premise of contingency, expressed as unprecedented human agency and human history. These effects can be accessed through the archaeological record and in the study of living languages. In addition, landscape transformation can be demonstrated in the study of traditional knowledge (TK. One way of elucidating TK distinctions between anthropic and nonanthropic landscapes concerns elicitation of differential labeling of these landscapes and more significantly, elicitation of the specific contents, such as trees, occurring in these landscapes. Freelisting is a method which can be used to distinguish the differential species compositions of landscapes resulting from human-mediated disturbance vs. those which do not evince records of human agency and history. The TK of the Ka’apor Indians of Amazonian Brazil as revealed in freelisting exercises shows differentiation of anthropogenic from high forests as well as a recognition of diversity in the anthropogenic forests. This suggests that the agents of human-mediated disturbance and landscape transformation in traditional Amazonia encode diversity and contingency into their TK, which encoding reflects past cultural influence on landscape and society over time.

  7. Machine learning for radioxenon event classification for the Comprehensive Nuclear-Test-Ban Treaty

    Energy Technology Data Exchange (ETDEWEB)

    Stocki, Trevor J., E-mail: trevor_stocki@hc-sc.gc.c [Radiation Protection Bureau, 775 Brookfield Road, A.L. 6302D1, Ottawa, ON, K1A 1C1 (Canada); Li, Guichong; Japkowicz, Nathalie [School of Information Technology and Engineering, University of Ottawa, 800 King Edward Avenue, Ottawa, ON, K1N 6N5 (Canada); Ungar, R. Kurt [Radiation Protection Bureau, 775 Brookfield Road, A.L. 6302D1, Ottawa, ON, K1A 1C1 (Canada)

    2010-01-15

    A method of weapon detection for the Comprehensive nuclear-Test-Ban-Treaty (CTBT) consists of monitoring the amount of radioxenon in the atmosphere by measuring and sampling the activity concentration of {sup 131m}Xe, {sup 133}Xe, {sup 133m}Xe, and {sup 135}Xe by radionuclide monitoring. Several explosion samples were simulated based on real data since the measured data of this type is quite rare. These data sets consisted of different circumstances of a nuclear explosion, and are used as training data sets to establish an effective classification model employing state-of-the-art technologies in machine learning. A study was conducted involving classic induction algorithms in machine learning including Naive Bayes, Neural Networks, Decision Trees, k-Nearest Neighbors, and Support Vector Machines, that revealed that they can successfully be used in this practical application. In particular, our studies show that many induction algorithms in machine learning outperform a simple linear discriminator when a signal is found in a high radioxenon background environment.

  8. Machine learning for radioxenon event classification for the Comprehensive Nuclear-Test-Ban Treaty

    International Nuclear Information System (INIS)

    Stocki, Trevor J.; Li, Guichong; Japkowicz, Nathalie; Ungar, R. Kurt

    2010-01-01

    A method of weapon detection for the Comprehensive nuclear-Test-Ban-Treaty (CTBT) consists of monitoring the amount of radioxenon in the atmosphere by measuring and sampling the activity concentration of 131m Xe, 133 Xe, 133m Xe, and 135 Xe by radionuclide monitoring. Several explosion samples were simulated based on real data since the measured data of this type is quite rare. These data sets consisted of different circumstances of a nuclear explosion, and are used as training data sets to establish an effective classification model employing state-of-the-art technologies in machine learning. A study was conducted involving classic induction algorithms in machine learning including Naive Bayes, Neural Networks, Decision Trees, k-Nearest Neighbors, and Support Vector Machines, that revealed that they can successfully be used in this practical application. In particular, our studies show that many induction algorithms in machine learning outperform a simple linear discriminator when a signal is found in a high radioxenon background environment.

  9. Photographed by the Earth: War and media in light of nuclear events

    Directory of Open Access Journals (Sweden)

    Thomas Pringle

    2014-12-01

    Full Text Available This article charts a media historical relation between radiation and celluloid film, ranging from the downwind 1956 production of The Conqueror to early scientific imaging practices, war photography, war documentaries, military industrial film, and contemporary artists working on radiation aesthetics. Posing the collection as a diagnostic media ecology, this article argues that the valuable evidence provided by the environmental metadata stored in celluloid film is the product of ecological warfare and violence. By turning to the material sciences for a better understanding of how nuclear weapons affect media on large spatial and temporal scales we gain a parallax view to how photographic practices – defined as the aesthetic exchange of light and energy – occur autonomously within our ecology, although some of these forces are mobilised in deadly and imperceptible ways. By demonstrating that non-human agencies released by Cold War energy policies have contaminated military industrial and commercial film archives alike, this article asserts that nuclear testing and warfare have contributed to a global condition of test-subjectivity that can be evidenced by diagnostic media ecology.

  10. Nuclear Forensics Attributing the Source of Spent Fuel Used in an RDD Event

    International Nuclear Information System (INIS)

    Scott, M.R.

    2005-01-01

    An RDD attack against the U.S. is something America needs to prepare against. If such an event occurs the ability to quickly identify the source of the radiological material used in an RDD would aid investigators in identifying the perpetrators. Spent fuel is one of the most dangerous possible radiological sources for an RDD. In this work, a forensics methodology was developed and implemented to attribute spent fuel to a source reactor. The specific attributes determined are the spent fuel burnup, age from discharge, reactor type, and initial fuel enrichment. It is shown that by analyzing the post-event material, these attributes can be determined with enough accuracy to be useful for investigators. The burnup can be found within a 5% accuracy, enrichment with a 2% accuracy, and age with a 10% accuracy. Reactor type can be determined if specific nuclides are measured. The methodology developed was implemented into a code call NEMASYS. NEMASYS is easy to use and it takes a minimum amount of time to learn its basic functions. It will process data within a few minutes and provide detailed information about the results and conclusions

  11. Nuclear Forensics Attributing the Source of Spent Fuel Used in an RDD Event

    Energy Technology Data Exchange (ETDEWEB)

    Scott, Mark Robert [Texas A & M Univ., College Station, TX (United States)

    2005-05-01

    An RDD attack against the U.S. is something America needs to prepare against. If such an event occurs the ability to quickly identify the source of the radiological material used in an RDD would aid investigators in identifying the perpetrators. Spent fuel is one of the most dangerous possible radiological sources for an RDD. In this work, a forensics methodology was developed and implemented to attribute spent fuel to a source reactor. The specific attributes determined are the spent fuel burnup, age from discharge, reactor type, and initial fuel enrichment. It is shown that by analyzing the post-event material, these attributes can be determined with enough accuracy to be useful for investigators. The burnup can be found within a 5% accuracy, enrichment with a 2% accuracy, and age with a 10% accuracy. Reactor type can be determined if specific nuclides are measured. The methodology developed was implemented into a code call NEMASYS. NEMASYS is easy to use and it takes a minimum amount of time to learn its basic functions. It will process data within a few minutes and provide detailed information about the results and conclusions.

  12. Generic implications of ATWS events at the Salem Nuclear Power Plant: generic implications. Vol. 1

    International Nuclear Information System (INIS)

    1983-04-01

    This report is the first of two volumes. It documents the work of an interoffice, interdisciplinary NRC Task Force established to determine the generic implications of two anticipated transients without scram (ATWS) at the Salem Nuclear Power Plant, Unit 1 on February 22 and 25, 1983. A second report will document the NRC actions to be taken based on the work of the Task Force. The Task Force was established to address three questions: (1) Is there a need for prompt action for similar equipment in other facilities. (2) Are NRC and its licensees learning the sefety-management lessons, and, (3) How should the priority and content of the ATWS rule be adjusted. A number of short-term actions were taken through Bulletins and an Information Notice. Intermediate-term actions to address the generic issues will be addressed in the separate report and implemented through appropriate regulatory mechanisms

  13. Investigative study on the technical code requirements of natural events hazards for nuclear power plants

    International Nuclear Information System (INIS)

    Ito, Kunio; Aoki, Takayuki

    2012-01-01

    Technical codes and standards on natural phenomena, in particular, earthquake and tsunami for nuclear power plants in the other developed countries including IAEA safety standards were investigated. Then, the results were compared with the corresponding Japanese technical codes and standards. As a results, it was found that: (1) technical codes and standards on natural phenomena, especially those for earthquakes and tsunami/flooding in those foreign countries and their requirements are all included in the Japanese technical codes and standards. (2) Nevertheless, the actual measures against tsunami/flooding in those foreign countries are more advanced than those in Japan which had been taken before Fukushima accident. Therefore, further investigation is needed to clarify the reason why there are such differences by investigating the details of the basic ideas and evaluation methods for the protection of tsunami/flooding. (author)

  14. 48 CFR 1318.201 - Contingency operation.

    Science.gov (United States)

    2010-10-01

    ... 48 Federal Acquisition Regulations System 5 2010-10-01 2010-10-01 false Contingency operation. 1318.201 Section 1318.201 Federal Acquisition Regulations System DEPARTMENT OF COMMERCE CONTRACTING METHODS AND CONTRACT TYPES EMERGENCY ACQUISITIONS Emergency Acquisition Flexibilities 1318.201 Contingency...

  15. 7 CFR 457.9 - Appropriation contingency.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 6 2010-01-01 2010-01-01 false Appropriation contingency. 457.9 Section 457.9 Agriculture Regulations of the Department of Agriculture (Continued) FEDERAL CROP INSURANCE CORPORATION, DEPARTMENT OF AGRICULTURE COMMON CROP INSURANCE REGULATIONS § 457.9 Appropriation contingency...

  16. Reporting, Recording, and Transferring Contingency Demand Data

    National Research Council Canada - National Science Library

    Smith, Bernard

    2000-01-01

    .... In this report, we develop a standard set of procedures for reporting and recording demand data at the contingency location and transferring contingency demand data to the home base - ensuring proper level allocation and valid worldwide peacetime operating stock (POS) and readiness spares package (RSP) requirements.

  17. Contingent and Alternative Work Arrangements, Defined.

    Science.gov (United States)

    Polivka, Anne E.

    1996-01-01

    Discusses the definitions of contingent workers and alternative work arrangements used by the Bureau of Labor Statistics to analyze data, and presents aggregate estimates of the number of workers in each group. Discusses the overlap between contingent workers and workers in alternative arrangements. (Author/JOW)

  18. Contingency management: perspectives of Australian service providers.

    Science.gov (United States)

    Cameron, Jacqui; Ritter, Alison

    2007-03-01

    Given the very positive and extensive research evidence demonstrating efficacy and effectiveness of contingency management, it is important that Australia explore whether contingency management has a role to play in our own treatment context. Qualitative interviews were conducted with 30 experienced alcohol and drug practitioners, service managers and policy-makers in Victoria. Interviewees were selected to represent the range of drug treatment services types and included rural representation. A semi-structured interview schedule, covering their perceptions and practices of contingency management was used. All interviews were transcribed verbatim and analysed using N2 qualitative data analysis program. The majority of key informants were positively inclined toward contingency management, notwithstanding some concerns about the philosophical underpinnings. Concerns were raised in relation to the use of monetary rewards. Examples of the use of contingency management provided by key informants demonstrated an over-inclusive definition: all the examples did not adhere to the key principles of contingency management. This may create problems if a structured contingency management were to be introduced in Australia. Contingency management is an important adjunctive treatment intervention and its use in Australia has the potential to enhance treatment outcomes. No unmanageable barriers were identified in this study.

  19. Contingent Attentional Capture by Conceptually Relevant Images

    Science.gov (United States)

    Wyble, Brad; Folk, Charles; Potter, Mary C.

    2013-01-01

    Attentional capture is an unintentional shift of visuospatial attention to the location of a distractor that is either highly salient, or relevant to the current task set. The latter situation is referred to as contingent capture, in that the effect is contingent on a match between characteristics of the stimuli and the task-defined…

  20. How to Cope with the Rare Human Error Events Involved with organizational Factors in Nuclear Power Plants

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Sa Kil; Luo, Meiling; Lee, Yong Hee [Korea Atomic Research Institute, Daejeon (Korea, Republic of)

    2014-10-15

    The current human error guidelines (e.g. US DOD handbooks, US NRC Guidelines) are representative tools to prevent human errors. These tools, however, have limits that they do not adapt all operating situations and circumstances such as design base events. In other words, these tools are only adapted foreseeable standardized operating situations and circumstances. In this study, our research team proposed an evidence-based approach such as UK's safety case to coping with the rare human error events such as TMI, Chernobyl, Fukushima accidents. These accidents are representative events involved with rare human errors. Our research team defined the 'rare human errors' as the follow three characterized events; Extremely low frequency Extremely high complicated structure Extremely serious damage of human life and property A safety case is a structured argument, supported by evidence, intended to justify that a system is acceptably safe. The definition by UK defense standard 00-56 issue 4 states that such an evidence-based approach can be contrast with a prescriptive approach to safety certification, which require safety to be justified using a prescribed process. Safety managements and safety regulatory activities based on safety case are effective to control organizational factors in terms of integrated safety management. Especially safety issues relevant with public acceptance are useful to provide practical evidences to the public reasonably. European Union including UK has developed the concept of engineered safety management system to deal with public acceptance using the safety case. In Korea nuclear industry, the Korean Atomic Research Institute has firstly performed a basic research to adapt the safety case in the field of radioactive waste according to the IAEA SSG-23(KAERI/TR-4497, 4531). Excepting the radioactive waste, there is no try to adapt the safety case yet. Most incidents and accidents involved human during operating NPPs have a tendency

  1. How to Cope with the Rare Human Error Events Involved with organizational Factors in Nuclear Power Plants

    International Nuclear Information System (INIS)

    Kim, Sa Kil; Luo, Meiling; Lee, Yong Hee

    2014-01-01

    The current human error guidelines (e.g. US DOD handbooks, US NRC Guidelines) are representative tools to prevent human errors. These tools, however, have limits that they do not adapt all operating situations and circumstances such as design base events. In other words, these tools are only adapted foreseeable standardized operating situations and circumstances. In this study, our research team proposed an evidence-based approach such as UK's safety case to coping with the rare human error events such as TMI, Chernobyl, Fukushima accidents. These accidents are representative events involved with rare human errors. Our research team defined the 'rare human errors' as the follow three characterized events; Extremely low frequency Extremely high complicated structure Extremely serious damage of human life and property A safety case is a structured argument, supported by evidence, intended to justify that a system is acceptably safe. The definition by UK defense standard 00-56 issue 4 states that such an evidence-based approach can be contrast with a prescriptive approach to safety certification, which require safety to be justified using a prescribed process. Safety managements and safety regulatory activities based on safety case are effective to control organizational factors in terms of integrated safety management. Especially safety issues relevant with public acceptance are useful to provide practical evidences to the public reasonably. European Union including UK has developed the concept of engineered safety management system to deal with public acceptance using the safety case. In Korea nuclear industry, the Korean Atomic Research Institute has firstly performed a basic research to adapt the safety case in the field of radioactive waste according to the IAEA SSG-23(KAERI/TR-4497, 4531). Excepting the radioactive waste, there is no try to adapt the safety case yet. Most incidents and accidents involved human during operating NPPs have a tendency

  2. Thevenin Equivalent Method for Dynamic Contingency Assessment

    DEFF Research Database (Denmark)

    Møller, Jakob Glarbo; Jóhannsson, Hjörtur; Østergaard, Jacob

    2015-01-01

    A method that exploits Thevenin equivalent representation for obtaining post-contingency steady-state nodal voltages is integrated with a method of detecting post-contingency aperiodic small-signal instability. The task of integrating stability assessment with contingency assessment is challenged...... by the cases of unstable post-contingency conditions. For unstable postcontingency conditions there exists no credible steady-state which can be used for basis of a stability assessment. This paper demonstrates how Thevenin Equivalent methods can be applied in algebraic representation of such bifurcation...... points which may be used in assessment of post-contingency aperiodic small-signal stability. The assessment method is introduced with a numeric example....

  3. Electrical systems at the nuclear power plant of Laguna Verde after the event in Fukushima; Sistemas electricos en la central nucleoelectrica Laguna Verde despues del evento de Fukushima

    Energy Technology Data Exchange (ETDEWEB)

    Lopez J, J. F., E-mail: jflopez@cnsns.gob.mx [Comision Nacional de Seguridad Nuclear y Salvaguardias, Dr. Jose M. Barragan 779, Col. Narvarte, 03020 Ciudad de Mexico (Mexico)

    2016-09-15

    During the event at the nuclear power plant of Fukushima Daichii (Japan), the electrical systems were affected both Onsite and Offsite, which were lost for a long time with irreversible consequences. Therefore, the Mexican Regulatory Body known as the Comision Nacional de Seguridad Nuclear y Salvaguardias (CNSNS) has taken various actions to review the current capacity of the electrical systems at the nuclear power plant of Laguna Verde (NPP-LV) before an event beyond the design bases. The CNSNS made special inspections to the NPP-LV to verify the current capacity of the electrical systems of Ac and Dc; as a result of the inspections, requirements were generated that must be met to demonstrate that has the capacity to deal with events beyond the design bases. In addition, CNSNS has participated in the Ibero-American Forum to deal with resistance testing. Is important to note that prior to the event at the nuclear power plant of Fukushima, the NPP-LV had implemented 1) the project Extended Power Increase in both Units of the NPP-LV, and 2) the Generic Charter 2006-02, both issues are considered contributions in the robustness of electrical systems. But it is also important to mention that the US Nuclear Regulatory Commission will soon issue mitigation strategies for a Station Blackout event, which could involve new actions at nuclear power plants. Based on the aforementioned, the CNSNS concludes that all the actions being taken contribute to the strengthening of the NPP-LV electrical systems, in order to increase their reliability, safety and operation when these are required to deal with events beyond the design bases as the event occurred in Fukushima Daichii and avoid as far as possible, damage in the reactor cores of the NPP-LV. (Author)

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

    International Nuclear Information System (INIS)

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

    1993-01-01

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

  5. The role of the fire dampers in the event of fire in a nuclear facility. Selection criteria for devices

    International Nuclear Information System (INIS)

    Savornin, J.; Laborde, J.C.

    1989-10-01

    In nuclear facilities, where unacceptable quantities of radioactive aerosols could be spread in the event of a fire, the ventilation system must be designed so that an underpressure is maintained under such circumstances. This is the reason why the extracting ventilation of the room in which the fire has broken out has generally to be kept going as long as possible. This prevents smoke and radioactive aerosols from spreading to accessways and adjacent rooms. Consequently, the various devices of the ventilation network need to have high fire resistance. Fire dampers can be applied to exhaust air to delay the heat build-up of a major fire. Specialized qualification testing is required for these dampers. The criteria we have used as a basis for specifying the required qualities of installations are defined. The tests that have been performed, or are now in progress, are described. The results obtained so far are given. Devices and arrangements are suggested

  6. Atmospheric dispersion modelling and the use of radiological data in the event of a nuclear accident overseas

    International Nuclear Information System (INIS)

    ApSimon, H.M.; Simms, K.L.

    1988-02-01

    This report considers what radiological measurements are most useful for use in conjunction with computer simulations based on meteorological data to provide the best possible estimates of areas affected and the likely levels of contamination in the event of a nuclear accident overseas. The context is defined according to the needs at different stages in emergency procedures - before radioactivity reaches the UK, during the period of passage overhead, after passage of the material. The ability to identify localised areas where precipitation has concentrated deposition is emphasized. It is made clear that γ detectors tend to be dominated by local levels of deposited activity and are inadequate to define when radioactivity is passing overhead. Facilities for airborne monitoring are recommended. (author)

  7. CNE (central nuclear en Embalse): probabilistic safety study. Loss-of-coolant accidents. Analysis through events sequence

    International Nuclear Information System (INIS)

    Layral, S.I.

    1987-01-01

    The aim of this study was to perform for the Embalse nuclear power plant, a probabilistic evaluation of loss-of-coolant accidents (LOCA) to identify the risks associated with them and to determine their acceptability in accordance with norms. This study includes all ruptures in the primary system that produce the automatic activation of 'emergency core cooling system'. Three starting events were selected for the probabilistic evaluation: 100% rupture of an input collector; 5% rupture of an input collector; 1.2% rupture of an input collector. At this stage the evaluation is focussed on the identification and quantization of the main failure sequences that follow a LOCA and lead to an uncontrolled reactor state or 'core meltdown'. The most important contribution to the core meltdown due to LOCA is the failure of supplies that are required for the emergency core cooling system. (Author)

  8. Contingency Contracting within the Department of Defense: A Comparative Analysis

    National Research Council Canada - National Science Library

    McMillion, Chester

    2000-01-01

    .... The thesis compares and contrasts the regulations governing the contingency contracting operations, the organization structure, contingency contracting support plans, and the training requirements...

  9. The Reinforcing Event (RE) Menu

    Science.gov (United States)

    Addison, Roger M.; Homme, Lloyd E.

    1973-01-01

    A motivational system, the Contingency Management System, uses contracts in which some amount of defined task behavior is demanded for some interval of reinforcing event. The Reinforcing Event Menu, a list of high probability reinforcing behaviors, is used in the system as a prompting device for the learner and as an aid for the administrator in…

  10. Optimistic bias and pessimistic realism in judgments of contingency with aversive or rewarding outcomes.

    Science.gov (United States)

    Sonoda, Akihito

    2002-10-01

    A depressive personality influences judgments of contingency. This is called "depressive realism." The present experiment examined whether optimistic traits, as measured by various scales, are correlated with judgments of contingency. The valences of the target stimuli were aversive or rewarding (noise avoidance or gaining points). Analysis indicated that the optimistic subjects (as measured by explanatory style for negative events) tend to overestimate noncontingent events; however, optimism measured by other scales did not show such an effect. The findings are discussed in terms of a self-defensive attributional bias.

  11. Invention principles and levels in the event of a nuclear accident

    International Nuclear Information System (INIS)

    Walmod-Larsen, O.

    1994-01-01

    In order to promote Nordic harmonization of the most likely protective measures to be taken in the case of large nuclear accidents, this report presents the background material needed to make common decisions on sheltering, evacuation and relocation. Brief comments only are also made on iodine prophylaxis and foodstuff restrictions. Viewing the national monetary costs per person for such measures in relation to the income per capita - and in relation to the currency exchange rates of Feb. 1994 - there are by and large no arguments to find for different intervention levels in any of the four countries, DK, NO, FI and SE. As applied α-values (the estimated monetary cost of a man-Sievert) are observed to have a large range, attempts were made to find the economic value of a health detriment. These pointed to the Willingness-To-Pay method, and a pilot project was performed in Denmark. On this basis a set of intervention levels - similar to internationally recommended levels -is proposed. Other factors influencing decisions in emergency situations are discussed. Risk perception, risk communication and psychological factors, as well as the modern decision-aiding tools capable of handling such factors are also described. (au) (47 refs.)

  12. Review of the Shoreham Nuclear Power Station Probabilistic Risk Assessment: internal events and core damage frequency

    International Nuclear Information System (INIS)

    Ilberg, D.; Shiu, K.; Hanan, N.; Anavim, E.

    1985-11-01

    A review of the Probabilistic Risk Assessment of the Shoreham Nuclear Power Station was conducted with the broad objective of evaluating its risks in relation to those identified in the Reactor Safety Study (WASH-1400). The scope of the review was limited to the ''front end'' part, i.e., to the evaluation of the frequencies of states in which core damage may occur. Furthermore, the review considered only internally generated accidents, consistent with the scope of the PRA. The review included an assessment of the assumptions and methods used in the Shoreham study. It also encompassed a reevaluation of the main results within the scope and general methodological framework of the Shoreham PRA, including both qualitative and quantitative analyses of accident initiators, data bases, and accident sequences which result in initiation of core damage. Specific comparisons are given between the Shoreham study, the results of the present review, and the WASH-1400 BWR, for the core damage frequency. The effect of modeling uncertainties was considered by a limited sensitivity study so as to show how the results would change if other assumptions were made. This review provides an independently assessed point value estimate of core damage frequency and describes the major contributors, by frontline systems and by accident sequences. 17 figs., 81 tabs

  13. Contemporary statistical procedures (Parametric Empirical Bayes) and nuclear plant event rates

    International Nuclear Information System (INIS)

    Gaver, D.P.; Worledge, D.H.

    1985-01-01

    The conduct of a nuclear power plant probabilistic risk assessment (PRA) recognizes that each of a great many vital components and systems is subject to failure. One aspect of the PRA procedure is to quantify individual item failure propensity, often in terms of the failure rate parameter of an exponential distribution or Poisson process, and then to combine rates so as to effectively infer the probability of plant failure, e.g., core damage. The formal method of combination of such rates involves use of fault-tree analysis. The defensibility of the final fault-tree result depends both upon the adequacy of the failure representations of its components, and upon the correctness and inclusiveness of the fault tree logic. This paper focuses upon the first issue, in particular, upon contemporary proposals for deriving estimates of individual rates. The purpose of the paper is to present, in basically non-mathematical terms, the essential nature of some of these proposals, and an assessment of how they might fit into, and contribute positively to, a more defensible or trustworthy PRA process

  14. Basic principles and criteria for public health protection in the event of a nuclear accident

    International Nuclear Information System (INIS)

    Kiradzhiev, G.

    1992-01-01

    Decision making criteria for population protection in nuclear accidents are discussed, and in particular the three basic principles: 1) excluding the appearance of nonstostochastic effects that occur in the case of high individual doses; 2) weighing the risks of radiation damage if such measures are not taken; 3) optimization based on comparison of benefit and costs, using the same measures for costs of health injury to affected populations and of the protected measures to be taken. The decision making criteria developed in Bulgaria are based on international recommendations with lowered upper limit of the range for evacuation and specified doses for vulnerable groups, children and pregnant women. The organization and the specific problems of the following individual types of protective measures are described: sheltering; protection of respiratory organs; iodine prophylaxis; evacuation of the public. One major condition for ensuring protection is to provide the public with timely information on the actual situation and the necessary countermeasures. Such information should be released in a manner that allows for understanding the expediency and significance of actions to be taken. An important aspect of emergency planning consists in taking into consideration the conditions actually prevailing in the country. This is well illustrated in the principle designated as 'national level of challenge' taking into account a country's capabilities for introducing intervention levels and permissible dose levels. In the case of Bulgaria this still remains to be done in protective planning for accidents. (author)

  15. Trend analysis of the adverse event cause in nuclear power plants

    International Nuclear Information System (INIS)

    Takagawa, Kenichi

    2010-01-01

    The adverse incidents which occurred in domestic and U. S. nuclear power plants during the period from 2003 to 2008 were classified by the cause classification method developed by INSS. From the results, it is clarified that the most frequent cause both in Japan and the U.S. is 'maintenance errors' accounting for approximately 40% of the total causes. Among 'maintenance errors', 'imperfect planning' is the most frequent one in the U. S. and increased from fiscal year 2007 in Japan. 'Workers error' has reduced its frequency by half in the U. S. and is staying at more frequent level in Japan. From the result of tendency analysis, corrective action against 'imperfect planning' and/or the effective use of incident information is thought to become effective to reduce the frequency of adverse incidents. Therefore, future subjects should include a study of alternative methods to analyze 'imperfect planning' which enable supplemented current RCA. At the same time, it should also be a theme to consider the proper ways of making incident reports to have the worker or planner easily extract lessons learned from them, as well as understanding the importance of utilizing incident information such as NUCIA. (author)

  16. Learning from nuclear regulatory self-assessment. International peer review of the CSN report on lessons learnt from the essential service water system degradation event at the Vandellos nuclear power plant

    International Nuclear Information System (INIS)

    2006-01-01

    Nuclear regulatory self-assessment together with the benchmarking of regulatory practices against those of other countries operating nuclear power plants are key elements in maintaining a high level of nuclear safety. In that light, the Spanish Consejo de Seguridad Nuclear (CSN) formally asked the OECD Nuclear Energy Agency (NEA) to establish an international peer review team to assess the CSN report on the lessons learnt as a result of the 2004 Vandellos II event involving essential service water system degradation. The International Review Team considers the CSN report prepared in follow-up to the Vandellos event to be a commendable effort in regulatory self-assessment. The report, complemented by this international peer review, should enable the CSN to take appropriate action to ensure that its regulatory supervision is in line with best international practice. (authors)

  17. Historical Contingency in Controlled Evolution

    Science.gov (United States)

    Schuster, Peter

    2014-12-01

    A basic question in evolution is dealing with the nature of an evolutionary memory. At thermodynamic equilibrium, at stable stationary states or other stable attractors the memory on the path leading to the long-time solution is erased, at least in part. Similar arguments hold for unique optima. Optimality in biology is discussed on the basis of microbial metabolism. Biology, on the other hand, is characterized by historical contingency, which has recently become accessible to experimental test in bacterial populations evolving under controlled conditions. Computer simulations give additional insight into the nature of the evolutionary memory, which is ultimately caused by the enormous space of possibilities that is so large that it escapes all attempts of visualization. In essence, this contribution is dealing with two questions of current evolutionary theory: (i) Are organisms operating at optimal performance? and (ii) How is the evolutionary memory built up in populations?

  18. Nuclear composition and energy spectra in the 1969 April 12 solar-particle event.

    Science.gov (United States)

    Bertsch, D. L.; Fichtel, C. E.; Reames, D. V.

    1972-01-01

    Measurement of the charge composition for several of the multicharged nuclei and the energy spectra for hydrogen, helium, and medium (6 less than or equal to Z less than or equal to 9) nuclei in the Apr. 12, 1969, solar-particle event. The energy/nucleon spectral shape of the medium nuclei was again the same as that of the helium nuclei, and the ratio of these two species was consistent with the present best average of 58 plus or minus 5. By combining the results obtained here with previous work, improved estimates of the Ne/O and Mg/O values of 0.16 plus or minus 0.03 and 0.056 plus or minus 0.014, respectively, were obtained. Silicon and sulfur abundances relative to O were determined to be 0.208 plus or minus 0.008 plus or minus 0.006, respectively, and 85% confidence upper limits for Ar and Ca relative to O of 0.017 and 0.010 were obtained. Previously, these last four nuclei had only been listed as a group.

  19. Hybrid instrument applied to human reliability study in event of loss of external electric power in a nuclear power plant

    International Nuclear Information System (INIS)

    Martins, Eduardo Ferraz

    2015-01-01

    The study projects in highly complex installations involves robust modeling, supported by conceptual and mathematical tools, to carry out systematic research and structured the different risk scenarios that can lead to unwanted events from occurring equipment failures or human errors. In the context of classical modeling, the Probabilistic Safety Analysis (PSA) seeks to provide qualitative and quantitative information about the project particularity and their operational facilities, including the identification of factors or scenarios that contribute to the risk and consequent comparison options for increasing safety. In this context, the aim of the thesis is to develop a hybrid instrument (CPP-HI) innovative, from the integrated modeling techniques of Failure Mode and Effect Analysis (FMEA), concepts of Human Reliability Analysis and Probabilistic Composition of Preferences (PCP). In support of modeling and validation of the CPP-HI, a simulation was performed on a triggering event 'Loss of External Electric Power' - PEEE, in a Nuclear Power plant. The results were simulated in a virtual environment (sensitivity analysis) and are robust to the study of Human Reliability Analysis (HRA) in the context of the PSA. (author)

  20. ACCRUAL OF LIABILITIES AND CONTINGENT ASSETS

    Directory of Open Access Journals (Sweden)

    Elena Ilie

    2011-12-01

    Full Text Available International Financial Reporting Standards together with Public Sector Accounting Standards are based on professional reasoning by appealing to principles that can lead to several solutions for a certain problem. In this respect Romanian economic mechanisms have a high level of rigidity in the implementation of accounting concepts and principles so that it is important to highlight the aspects that generate added value in the current economic climate. Even since 2005 the harmonization of Romanian accounting with the directives of International Accounting Standards, which came to support the harmonization of rules and principles concerning the development of annual financial statements of public institutions, is the most important and essential challenge for administrative environment. Assets and contingent liabilities are elements which in terms of the law cannot be included in the assets of a public institution that is why accounting of these elements must be performed using special off-balance sheet accounts. The purpose of this work emphasizes the opportunity and the recognition of economic events whose elements should be reflected in balance sheet, but also the appropriate and necessary moment of making entries over special accounts off the balance sheet in accordance with IPSAS 19.

  1. Role of cytogenetic biodosimetry in meeting the needs of a mass casualty radiological/nuclear event

    International Nuclear Information System (INIS)

    Balajee, A.S.; Dainiak, N.

    2016-01-01

    Radiological/nuclear (R/N) terrorism constitutes a potential threat to all nations that can result in significant morbidity and mortality among hundreds of thousands individuals. In addition to the timing and severity of clinical signs and symptoms, individual radiation dose informs risk assessment and mitigation of radiation-associated injuries. The 'gold standard' for individual whole-body radiation dosimetry is the dicentric chromosome assay. The Cytogenetics Biodosimetry Laboratory at REAC/TS is a WHO Collaborating Centre and member of IAEA's RANET that employs DCA, as well as fluorescence in situ hybridization, premature chromosome condensation, and micronuclei assays to assess radiation dose. The quality of dose estimates and standard operating procedures for DCA at REAC/TS have been validated in multiple inter-comparison studies involving CBLs in Asia, Europe, North America and South America. DCA is scalable to meet the needs of a mass casualty R/N incident. The CBL at REAC/TS has made seminal contributions to augment surge capacity for DCA and develop CBLs worldwide through initiatives such as modification of 'Share Point' in 2010 to transmit images of metaphases for simultaneous telescoring; (2) development of an on-line training program for metaphase scoring; (3) proactive participation as a WCC to create ISO standards; and (4) guidance of regulatory agencies to monitor quality of results and SOPs. The precision of dose estimates by DCA can be vastly improved by using a universal calibration curve. With this view, REAC/TS has organized a collaboration with CBLs at Health Canada and Yale University to construct and validate a common calibration curve for gamma rays

  2. Why are parasite contingency genes often associated with telomeres?

    Science.gov (United States)

    Barry, J D; Ginger, M L; Burton, P; McCulloch, R

    2003-01-01

    Contingency genes are common in pathogenic microbes and enable, through pre-emptive mutational events, rapid, clonal switches in phenotype that are conducive to survival and proliferation in hosts. Antigenic variation, which is a highly successful survival strategy employed by eubacterial and eukaryotic pathogens, involves large repertoires of distinct contingency genes that are expressed differentially, enabling evasion of host acquired immunity. Most, but not all, antigenic variation systems make extensive use of subtelomeres. Study of model systems has shown that subtelomeres have unusual properties, including reversible silencing of genes mediated by proteins binding to the telomere, and engagement in ectopic recombination with other subtelomeres. There is a general theory that subtelomeric location confers a capacity for gene diversification through such recombination, although experimental evidence is that there is no increased mitotic recombination at such loci and that sequence homogenisation occurs. Possible benefits of subtelomeric location for pathogen contingency systems are reversible gene silencing, which could contribute to systems for gene switching and mutually exclusive expression, and ectopic recombination, leading to gene family diversification. We examine, in several antigenic variation systems, what possible benefits apply.

  3. Multi-tasking Sulf1/Sulf2 enzymes do not only facilitate extracellular cell signalling but also participate in cell cycle related nuclear events.

    Science.gov (United States)

    Krishnakumar, Kavithanjali; Chakravorty, Ishani; Foy, Wendy; Allen, Steve; Justo, Tiago; Mukherjee, Abir; Dhoot, Gurtej K

    2018-03-01

    This study demonstrates highly dynamic spatial and temporal pattern of SULF1/SULF2 expression in a number of neuronal cell types growing in normal culture medium that included their transient nuclear mobilisation. Their nuclear translocation became particularly apparent during cell proliferation as both SULF1/SULF2 demonstrated not only cell membrane associated expression, their known site of function but also transient nuclear mobilisation during nuclear cell division. Nuclear localisation was apparent not only by immunocytochemical staining but also confirmed by immunoblotting staining of isolated nuclear fractions of C6, U87 and N2A cells. Immunocytochemical analysis demonstrated rapid nuclear exit of both SULF1/SULF2 following cell division that was slightly delayed but not blocked in a fraction of the polyploid cells observed in C6 cells. The overexpression of both Sulf1 and Sulf2 genes in C6 and U87 cells markedly promoted in vitro growth of these cells accompanied by nuclear mobilisation while inhibition of both these genes inhibited cell proliferation with little or no nuclear SULF1/SULF2 mobilisation. SULF1/SULF2 activity in these cells thus demonstrated a clear co-ordination of extracellular cell signalling with nuclear events related to cell proliferation. Crown Copyright © 2018. Published by Elsevier Inc. All rights reserved.

  4. Equilibria of perceptrons for simple contingency problems.

    Science.gov (United States)

    Dawson, Michael R W; Dupuis, Brian

    2012-08-01

    The contingency between cues and outcomes is fundamentally important to theories of causal reasoning and to theories of associative learning. Researchers have computed the equilibria of Rescorla-Wagner models for a variety of contingency problems, and have used these equilibria to identify situations in which the Rescorla-Wagner model is consistent, or inconsistent, with normative models of contingency. Mathematical analyses that directly compare artificial neural networks to contingency theory have not been performed, because of the assumed equivalence between the Rescorla-Wagner learning rule and the delta rule training of artificial neural networks. However, recent results indicate that this equivalence is not as straightforward as typically assumed, suggesting a strong need for mathematical accounts of how networks deal with contingency problems. One such analysis is presented here, where it is proven that the structure of the equilibrium for a simple network trained on a basic contingency problem is quite different from the structure of the equilibrium for a Rescorla-Wagner model faced with the same problem. However, these structural differences lead to functionally equivalent behavior. The implications of this result for the relationships between associative learning, contingency theory, and connectionism are discussed.

  5. ACCOUNTING FOR CONTINGENT CONSIDERATIONS IN BUSINESS COMBINATIONS

    Directory of Open Access Journals (Sweden)

    Gurgen KALASHYAN

    2017-07-01

    Full Text Available According to IFRS 3 Business Combinations contingent considerations must be included in the total consideration given for the acquired entity along with cash, other assets, ordinary or preference equity instruments, options, warrants. The contingent consideration is the determined amount which acquiring entity has to pay to acquired entity provided, that certain conditions will be fulfilled in the future. In case the provisions are not satisfied, we will get the situation when the amount of contingent consideration has been included in the total consideration given in the business combination, but in fact, the acquirer has not paid that amount. In its turn, the acquired entity will recognize the contingent consideration as a financial asset according to IFRS 9 Financial Instruments. In that case, it would be appropriately to recognize the contingent consideration as a contingent asset applying IAS 37. In the Article the author will explore the challenges of contingent consideration accounting and suggest the ways of solving the above mentioned problems.

  6. Crayfish Self-Administer Amphetamine in a Spatially Contingent Task

    Directory of Open Access Journals (Sweden)

    Udita Datta

    2018-05-01

    Full Text Available Natural reward is an essential element of any organism’s ability to adapt to environmental variation. Its underlying circuits and mechanisms guide the learning process as they help associate an event, or cue, with the perception of an outcome’s value. More generally, natural reward serves as the fundamental generator of all motivated behavior. Addictive plant alkaloids are able to activate this circuitry in taxa ranging from planaria to humans. With modularly organized nervous systems and confirmed vulnerabilities to human drugs of abuse, crayfish have recently emerged as a compelling model for the study of the addiction cycle, including psychostimulant effects, sensitization, withdrawal, reinstatement, and drug reward in conditioned place preference paradigms. Here we extend this work with the demonstration of a spatially contingent, operant drug self-administration paradigm for amphetamine. When the animal enters a quadrant of the arena with a particular textured substrate, a computer-based control system delivers amphetamine through an indwelling fine-bore cannula. Resulting reward strength, dose-response, and the time course of operant conditioning were assessed. Individuals experiencing the drug contingent on their behavior, displayed enhanced rates of operant responses compared to that of their yoked (non-contingent counterparts. Application of amphetamine near the supra-esophageal ganglion elicited stronger and more robust increases in operant responding than did systemic infusions. This work demonstrates automated implementation of a spatially contingent self-administration paradigm in crayfish, which provides a powerful tool to explore comparative perspectives in drug-sensitive reward, the mechanisms of learning underlying the addictive cycle, and phylogenetically conserved vulnerabilities to psychostimulant compounds.

  7. Classification of radiation-hazardous objects by the ecological risk rate, based on the concept of the International Nuclear Event Scale (INES)

    International Nuclear Information System (INIS)

    Vetrov, V.A.

    2003-01-01

    The principal categories of the radiation-hazardous objects (RHO) (nuclear fuel cycle plants (NFC including NPP); ships with nuclear engine units and appropriate service facilities; units related with nuclear weapons (design, manufacture, storage, etc.); contaminated territories in the result nuclear accidents and nuclear facilities tests; civil enterprises using the radioactive sources) with real accident risk from radioactive substances (RS) release into environment are considered. For assessment of the ecological risk rate from RHO the International Nuclear Event Scale implemented by IAEA for NPP use is suggested. By opinion of the specialists the INES criteria could be used for radiation events assessment to other RHO that gives possibility for RHO arrangement by the potential hazard rate for environment in the case of accident. For RHO qualitative classification the main parameters assessment influencing on radioactive release risk (amount (total activity) of radioactive substances; possibility of chain reaction development; strength of technological parameters, etc.) was suggested. On the base of the INES all above-listed RHO kinds in the case of accident could be conditionally separated into three categories: 1. most radiation dangerous objects, on which could be severe and serious radiation accidents (corresponding to 4-7 INES levels); 2. RHO on which there is risk for accidents accompanying with RS release (accidents up to 4 INES level). 3. RHO without practical possibility for event (incidents - not higher 3 INES level). Introduction of suggested classification gives possibility for RHO safety control requirements rationalizing to radiation monitoring purposes for both RHO and the local systems

  8. Development of an event-driven parser for active document and web-based nuclear design system

    Energy Technology Data Exchange (ETDEWEB)

    Park, Yong Soo

    2005-02-15

    Nuclear design works consist of extensive unit job modules in which many computer codes are used. Each unit module requires time-consuming and erroneous input preparation, code run, output analysis and quality assurance process. The task for safety evaluation of reload core is especially the most man-power intensive and time-consuming due to the large amount of calculations and data exchanges. The purpose of this study is to develop a new nuclear design system called Innovative Design Processor (IDP) in order to minimize human effort and maximize design quality and productivity, and then to achieve an ultimately optimized core loading pattern. Two new basic principles of IDP are the document-oriented design and the web based design. Contrary to the conventional code-oriented or procedure-oriented design, the document-oriented design is human-oriented in that the final document is automatically prepared with complete analysis, table and plots, if the designer writes a design document called active document and feeds it to a parser. This study defined a number of active components and developed an event-driven parser for the active document in HTML (Hypertext Markup Language) or XML (Extensible Markup Language). The active documents can be created on the web, which is another framework of IDP. Using proper mix-up of server side and client side programming under the HAMP (HP-UX/Apache/MySQL/PHP) environment, the document-oriented design process on the web is modeled as a design wizard for designer's convenience and platform independency. This automation using IDP was tested for the reload safety evaluation of Korea Standard Nuclear Power Plant (KSNP) type PWRs. Great time saving was confirmed and IDP can complete several-month jobs in a few days. More optimized core loading pattern, therefore, can be obtained since it takes little time to do the reload safety evaluation tasks with several core loading pattern candidates. Since the technology is also applicable to

  9. Development of an event-driven parser for active document and web-based nuclear design system

    International Nuclear Information System (INIS)

    Park, Yong Soo

    2005-02-01

    Nuclear design works consist of extensive unit job modules in which many computer codes are used. Each unit module requires time-consuming and erroneous input preparation, code run, output analysis and quality assurance process. The task for safety evaluation of reload core is especially the most man-power intensive and time-consuming due to the large amount of calculations and data exchanges. The purpose of this study is to develop a new nuclear design system called Innovative Design Processor (IDP) in order to minimize human effort and maximize design quality and productivity, and then to achieve an ultimately optimized core loading pattern. Two new basic principles of IDP are the document-oriented design and the web based design. Contrary to the conventional code-oriented or procedure-oriented design, the document-oriented design is human-oriented in that the final document is automatically prepared with complete analysis, table and plots, if the designer writes a design document called active document and feeds it to a parser. This study defined a number of active components and developed an event-driven parser for the active document in HTML (Hypertext Markup Language) or XML (Extensible Markup Language). The active documents can be created on the web, which is another framework of IDP. Using proper mix-up of server side and client side programming under the HAMP (HP-UX/Apache/MySQL/PHP) environment, the document-oriented design process on the web is modeled as a design wizard for designer's convenience and platform independency. This automation using IDP was tested for the reload safety evaluation of Korea Standard Nuclear Power Plant (KSNP) type PWRs. Great time saving was confirmed and IDP can complete several-month jobs in a few days. More optimized core loading pattern, therefore, can be obtained since it takes little time to do the reload safety evaluation tasks with several core loading pattern candidates. Since the technology is also applicable to the

  10. Modalities of declaration and codification of criteria related to significant events in the field of radioprotection besides base nuclear installations and transports of radioactive substances

    International Nuclear Information System (INIS)

    2009-01-01

    This document specifies provisions which must be applied by those in charge of a nuclear activity when declaring significant events regarding radioprotection. It describes the general principles, evokes the declaration criteria (they are more precisely presented in appendix), the declaration delay, and the declaration modalities (the informant, the documents, the addressee). It also evokes obligations regarding population information. A declaration form and a model of event report are provided in appendix

  11. Cooperation in the Event of Nuclear Accidents; Cooperation en Matiere d'Accidents Nucleaires

    Energy Technology Data Exchange (ETDEWEB)

    Bresson, G. [CEA, Centre d' etudes nucleaires, de Fontenay-aux-Roses (France)

    1969-10-15

    This paper is concerned only with the action to be taken in respect of an individual directly affected by an accident and not with the more general measures relating to the population as a whole. Keeping the same sequence of ideas, the paper deals with nuclear establishments and cites criteria for classifying them; hence only the relationship between the establishment and the hospital, and between the radiation protection experts and medical personnel, is discussed. The complex organization of emergency measures, reception of the victim of the accident, and the treatment possibly required should be based on standard practice and published material, both national and international, allowance being made for the characteristics of each sector. A ''flexible'' plan of co-ordination is given as an illustration. Action must be taken in such cases at the site of the accident, inside and outside the establishment, and above all at the hospital. All categories of persons are involved in the process, i.e. fellow-workers, management, specialized services, and medical personnel, each with their own part to play. The manpower and equipment brought into service therefore vary, and depend upon the internal and external relations maintained by the establishment. The measures envisaged should provide for the transport, reception and treatment of those involved in the accident. An existing organization of this kind is described as an illustration. Finally, no action can be of value without full knowledge of the facts and thorough training of the personnel. Some clearly defined ideas on the.subject are considered under this heading. (author) [French] Le memoire ne traite que de la conduite a tenir envers un accidente et non du probleme, plus general, des mesures relatives a une population. Dans le meme ordre d'idees, l'etude porte sur les etablissements nucleaires et leurs criteres de classement; il ne s'agit donc que des liaisons entre retablissement et l'hopital et entre les

  12. Case Study on Influence Factor Trend Analysis of the Accidents and Events of Nuclear Power Plants by applying Nuclear Safety Culture Framework

    Energy Technology Data Exchange (ETDEWEB)

    Park, J. Y.; Park, Y. W.; Park, H.G. [KAIST, Daejeon (Korea, Republic of)

    2016-05-15

    This study 1) established the standard based on frameworks of safety culture principles that show safety culture promotion goals, 2) analyzed the linkages with the frameworks that were established by analyzing each incident cause and weak point from selected 268 cases(rating over INES grade 1) among 4,088 cases (as of April 1, 2015). The 4,088 cases were selected as a result of database analysis from 702 accidents recorded in accident and rating evaluation reports that were published in the National Nuclear Safety Commission and overseas IRS (International Reporting System for operating Experience), and 3) finally conducted a trend analysis studies with these comprehensive results. From the investigations, followings were concluded. 1) In order to analyze the safety culture, analysis methodology is required. 2) Analytical methodology for building sustainable safety culture promoting a virtuous cycle system was developed 3) Among variety of process input data, 970 domestic and overseas incidents were selected as targets and 502 accidents were classified as safety culture related events by utilizing screen filter of IAEA GS-G-3.5 Appendix I and Framework (Nuclear Safety Culture Base Frame) developed by BEES, Inc. for safety culture analysis method. 4) As a result, complex safety culture influence factors for the one reason which was difficult to separate by conventional methods was able to be analyzed. 5) The cumulative data through the system was results of virtuous trend analysis rather than temporary results. Thus, it could be unique cultural factors of the domestic industry and could derive trend differences for domestic safety culture factors accordingly.

  13. Trans-oceanic transport of {sup 137}Cs from the Fukushima nuclear accident and impact of hypothetical Fukushima-like events of future nuclear plants in Southern China

    Energy Technology Data Exchange (ETDEWEB)

    Wai, Ka-Ming, E-mail: bhkmwai@cityu.edu.hk [Department of Geological and Mining Engineering and Sciences, Michigan Technological University, Houghton, MI (United States); Department of Physics and Material Science, City University of Hong Kong, Hong Kong (China); Yu, Peter K.N. [Department of Physics and Material Science, City University of Hong Kong, Hong Kong (China)

    2015-03-01

    A Lagrangian model was adopted to assess the potential impact of {sup 137}Cs released from hypothetical Fukushima-like accidents occurring on three potential nuclear power plant sites in Southern China in the near future (planned within 10 years) in four different seasons. The maximum surface (0–500 m) {sup 137}Cs air concentrations would be reached 10 Bq m{sup −3} near the source, comparable to the Fukushima case. In January, Southeast Asian countries would be mostly affected by the radioactive plume due to the effects of winter monsoon. In April, the impact would be mainly on Southern and Northern China. Debris of radioactive plume (∼ 1 mBq m{sup −3}) would carry out long-range transport to North America. The area of influence would be the smallest in July due to the frequent and intense wet removal events by trough of low pressure and tropical cyclone. The maximum worst-case areas of influence were 2382000, 2327000, 517000 and 1395000 km{sup 2} in January, April, July and October, respectively. Prior to the above calculations, the model was employed to simulate the trans-oceanic transport of {sup 137}Cs from the Fukushima nuclear accident. Observed and modeled {sup 137}Cs concentrations were comparable. Sensitivity runs were performed to optimize the wet scavenging parameterization. The adoption of higher-resolution (1° × 1°) meteorological fields improved the prediction. The computed large-scale plume transport pattern over the Pacific Ocean was compared with that reported in the literature. - Highlights: • A Lagrangian model was used to predict the dispersion of {sup 137}Cs from plant accident. • Observed and modeled {sup 137}Cs concentrations were comparable for the Fukushima accident. • The maximum surface concentrations could reach 10 Bq m{sup −3} for the hypothetical case. • The hypothetical radiative plumes could impact E/SE Asia and N. America.

  14. Case Study on Influence Factor Trend Analysis of the Accidents and Events of Nuclear Power Plants by applying Nuclear Safety Culture Framework

    International Nuclear Information System (INIS)

    Park, J. Y.; Park, Y. W.; Park, H.G.

    2016-01-01

    This study 1) established the standard based on frameworks of safety culture principles that show safety culture promotion goals, 2) analyzed the linkages with the frameworks that were established by analyzing each incident cause and weak point from selected 268 cases(rating over INES grade 1) among 4,088 cases (as of April 1, 2015). The 4,088 cases were selected as a result of database analysis from 702 accidents recorded in accident and rating evaluation reports that were published in the National Nuclear Safety Commission and overseas IRS (International Reporting System for operating Experience), and 3) finally conducted a trend analysis studies with these comprehensive results. From the investigations, followings were concluded. 1) In order to analyze the safety culture, analysis methodology is required. 2) Analytical methodology for building sustainable safety culture promoting a virtuous cycle system was developed 3) Among variety of process input data, 970 domestic and overseas incidents were selected as targets and 502 accidents were classified as safety culture related events by utilizing screen filter of IAEA GS-G-3.5 Appendix I and Framework (Nuclear Safety Culture Base Frame) developed by BEES, Inc. for safety culture analysis method. 4) As a result, complex safety culture influence factors for the one reason which was difficult to separate by conventional methods was able to be analyzed. 5) The cumulative data through the system was results of virtuous trend analysis rather than temporary results. Thus, it could be unique cultural factors of the domestic industry and could derive trend differences for domestic safety culture factors accordingly

  15. Contingency-Constrained Unit Commitmentin Meshed Isolated Power Systems

    DEFF Research Database (Denmark)

    Sokoler, Leo Emil; Vinter, Peter; Bærentsen, Runi

    2015-01-01

    is kept above a predefined limit in the event of a contingency. The minimum frequency constraints are formulated using novel sufficient conditions that take into account the system inertia and the dynamics of the power generators. The proposed sufficient conditions are attractive from both a computational...... and a modelling point of view. We compare the ORPP to a unit commitment problem that only considers the stationary behavior of the frequency. Simulations based on a Faroe Islands case study show that, without being overly conservative, potential blackouts and power outages can be avoided using the ORPP...

  16. 40 CFR 265.54 - Amendment of contingency plan.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 25 2010-07-01 2010-07-01 false Amendment of contingency plan. 265.54... DISPOSAL FACILITIES Contingency Plan and Emergency Procedures § 265.54 Amendment of contingency plan. The contingency plan must be reviewed, and immediately amended, if necessary, whenever: (a) Applicable regulations...

  17. 40 CFR 265.53 - Copies of contingency plan.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 25 2010-07-01 2010-07-01 false Copies of contingency plan. 265.53... DISPOSAL FACILITIES Contingency Plan and Emergency Procedures § 265.53 Copies of contingency plan. A copy of the contingency plan and all revisions to the plan must be: (a) Maintained at the facility; and (b...

  18. 40 CFR 264.54 - Amendment of contingency plan.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 25 2010-07-01 2010-07-01 false Amendment of contingency plan. 264.54 Section 264.54 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) SOLID WASTES... Contingency Plan and Emergency Procedures § 264.54 Amendment of contingency plan. The contingency plan must be...

  19. Does Explosive Nuclear Burning Occur in Tidal Disruption Events of White Dwarfs by Intermediate-mass Black Holes?

    Energy Technology Data Exchange (ETDEWEB)

    Tanikawa, Ataru; Sato, Yushi; Hachisu, Izumi [Department of Earth Science and Astronomy, College of Arts and Sciences, The University of Tokyo, 3-8-1 Komaba, Meguro-ku, Tokyo 153-8902 (Japan); Nomoto, Ken’ichi; Maeda, Keiichi [Kavli Institute for the Physics and Mathematics of the Universe (WPI), The University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa, Chiba 277-8583 (Japan); Nakasato, Naohito, E-mail: tanikawa@ea.c.u-tokyo.ac.jp [Department of Computer Science and Engineering, University of Aizu, Tsuruga Ikki-machi Aizu-Wakamatsu, Fukushima 965-8580 (Japan)

    2017-04-20

    We investigate nucleosynthesis in tidal disruption events (TDEs) of white dwarfs (WDs) by intermediate-mass black holes. We consider various types of WDs with different masses and compositions by means of three-dimensional (3D) smoothed particle hydrodynamics (SPH) simulations. We model these WDs with different numbers of SPH particles, N , from a few 10{sup 4} to a few 10{sup 7} in order to check mass resolution convergence, where SPH simulations with N > 10{sup 7} (or a space resolution of several 10{sup 6} cm) have unprecedentedly high resolution in this kind of simulation. We find that nuclear reactions become less active with increasing N and that these nuclear reactions are excited by spurious heating due to low resolution. Moreover, we find no shock wave generation. In order to investigate the reason for the absence of a shock wave, we additionally perform one-dimensional (1D) SPH and mesh-based simulations with a space resolution ranging from 10{sup 4} to 10{sup 7} cm, using a characteristic flow structure extracted from the 3D SPH simulations. We find shock waves in these 1D high-resolution simulations, one of which triggers a detonation wave. However, we must be careful of the fact that, if the shock wave emerged in an outer region, it could not trigger the detonation wave due to low density. Note that the 1D initial conditions lack accuracy to precisely determine where a shock wave emerges. We need to perform 3D simulations with ≲10{sup 6} cm space resolution in order to conclude that WD TDEs become optical transients powered by radioactive nuclei.

  20. Retrospective and emergency dosimetry in response to radiological incidents and nuclear mass-casualty events: A review

    International Nuclear Information System (INIS)

    Bailiff, I.K.; Sholom, S.; McKeever, S.W.S.

    2016-01-01

    This paper reviews recent research on the application of the physical dosimetry techniques of electron paramagnetic resonance (EPR) and luminescence (optically stimulated luminescence, OSL, and thermoluminescence, TL) to determine radiation dose following catastrophic, large-scale radiological events. Such data are used in dose reconstruction to obtain estimates of dose due to the exposure to external sources of radiation, primarily gamma radiation, by individual members of the public and by populations. The EPR and luminescence techniques have been applied to a wide range of radiological studies, including nuclear bomb detonation (e.g., Hiroshima and Nagasaki), nuclear power plant accidents (e.g., Chernobyl), radioactive pollution (e.g., Mayak plutonium facility), and in the future could include terrorist events involving the dispersal of radioactive materials. In this review we examine the application of these techniques in ‘emergency’ and ‘retrospective’ modes of operation that are conducted on two distinct timescales. For emergency dosimetry immediate action to evaluate dose to individuals following radiation exposure is required to assess deterministic biological effects and to enable rapid medical triage. Retrospective dosimetry, on the other hand, contributes to the reconstruction of doses to populations and individuals following external exposure, and contributes to the long-term study of stochastic processes and the consequential epidemiological effects. Although internal exposure, via ingestion of radionuclides for example, can be a potentially significant contributor to dose, this review is confined to those dose components arising from exposure to external radiation, which in most studies is gamma radiation. The nascent emergency dosimetry measurement techniques aim to perform direct dose evaluations for individuals who, as members of the public, are most unlikely to be carrying a dosimeter issued for radiation monitoring purposes in the event

  1. The Corps Engineer Battalion in Contingency Operations

    National Research Council Canada - National Science Library

    Raymer, James

    2001-01-01

    .... The central research question asks: Is the proposed echelons above division engineer battalion design a better one for active and reserve component corps engineer forces to respond in a contingency...

  2. Strategy as Mutually Contingent Choice

    Directory of Open Access Journals (Sweden)

    Neil Martin

    2016-05-01

    Full Text Available Thomas Schelling’s The Strategy of Conflict carries significant behavioral implications which have been overlooked by economic readers. I argue that these implications are central to Schelling’s vision of game theory, that they fit well with recent advances in experimental psychology and behavioral economics, and provide a comprehensive framework that can inform research on strategy. In my view, Schelling develops a non-mathematical approach to strategy which anticipates on Gigerenzer and Selten’s “ecological rationality” program. This approach maps the processes involved in strategic reasoning and highlights their reliance on the particular information structure of interactive social environments. Building on this approach, I model strategy as a heuristic form of reasoning that governs the way in which individuals search for and provide cues in situations of mutually contingent choice. I conclude by examining how the reference to ecological rationality can help clarify Schelling’s contribution to game theory and outline potential avenues of research into strategic reasoning and interaction.

  3. Modeling time to recovery and initiating event frequency for loss of off-site power incidents at nuclear power plants

    International Nuclear Information System (INIS)

    Iman, R.L.; Hora, S.C.

    1988-01-01

    Industry data representing the time to recovery of loss of off-site power at nuclear power plants for 63 incidents caused by plant-centered losses, grid losses, or severe weather losses are fit with exponential, lognormal, gamma and Weibull probability models. A Bayesian analysis is used to compare the adequacy of each of these models and to provide uncertainty bounds on each of the fitted models. A composite model that combines the probability models fitted to each of the three sources of data is presented as a method for predicting the time to recovery of loss of off-site power. The composite model is very general and can be made site specific by making adjustments on the models used, such as might occur due to the type of switchyard configuration or type of grid, and by adjusting the weights on the individual models, such as might occur with weather conditions existing at a particular plant. Adjustments in the composite model are shown for different models used for switchyard configuration and for different weights due to weather. Bayesian approaches are also presented for modeling the frequency of initiating events leading to loss of off-site power. One Bayesian model assumes that all plants share a common incidence rate for loss of off-site power, while the other Bayesian approach models the incidence rate for each plant relative to the incidence rates of all other plants. Combining the Bayesian models for the frequency of the initiating events with the composite Bayesian model for recovery provides the necessary vehicle for a complete model that incorporates uncertainty into a probabilistic risk assessment

  4. Probabilistic real-time contingency ranking method

    International Nuclear Information System (INIS)

    Mijuskovic, N.A.; Stojnic, D.

    2000-01-01

    This paper describes a real-time contingency method based on a probabilistic index-expected energy not supplied. This way it is possible to take into account the stochastic nature of the electric power system equipment outages. This approach enables more comprehensive ranking of contingencies and it is possible to form reliability cost values that can form the basis for hourly spot price calculations. The electric power system of Serbia is used as an example for the method proposed. (author)

  5. ACCOUNTING FOR CONTINGENT CONSIDERATIONS IN BUSINESS COMBINATIONS

    OpenAIRE

    Gurgen KALASHYAN

    2017-01-01

    According to IFRS 3 Business Combinations contingent considerations must be included in the total consideration given for the acquired entity along with cash, other assets, ordinary or preference equity instruments, options, warrants. The contingent consideration is the determined amount which acquiring entity has to pay to acquired entity provided, that certain conditions will be fulfilled in the future. In case the provisions are not satisfied, we will get the situation when the amount of c...

  6. The Contingent Value of Organizational Integration

    Directory of Open Access Journals (Sweden)

    Virpi Turkulainen

    2013-08-01

    Full Text Available We elaborate the link between organizational design and effectiveness by examining organizational integration and performance in the context of modern manufacturing. Through careful contextualization and empirical analysis of 266 manufacturing organizations in three industries and nine countries, we uncover a joint effect of integration and complexity on organizational effectiveness. The results extend structural contingency theory, in particular the mechanisms that link organizational integration to organizational effectiveness. We conclude by discussing the continuing relevance of structural contingency theory.

  7. Proceedings of the meeting of a task force on problems of rare events in the reliability analysis of nuclear power plants

    International Nuclear Information System (INIS)

    1976-01-01

    In safety problems of nuclear plants interest centres on various types of rare events. These may extend from rare modes of failures in the component parts of the system and plant, the simultaneous occurrence of a very low resistance of a structural member and an extremely high load, to rare catastrophic failures which affect whole plant and system complexes. The obvious need is therefore to understand the patterns of behaviour of these events in space and time domains and be able to make some adequate estimate of their probability of occurrence. In 1975, a Task Force of Experts on the Statistical Analysis of Rare Events in Nuclear Installations was set up, its main objective being to explore methods for handling the problems of reliability analysis involving rare events. The main topic area of the Ispra meeting concerns the statistical analysis of structures such as containment and pressure vessels, automatic protection systems, and allied items, with a view to giving a quantified probabilistic statement on particular reliability characteristics. The particular subjects covered by the invited experts who would normally be working in specialized fields, includes, specifically, statistical modelling of rare events, decision theory applied to rare events, small sampling theory in the case of rare events. Man-made phenomena as well as natural phenomena are also considered, as they involve different approaches to modelling. 22 papers are presented, with reports on group discussions

  8. Nuclear accidents

    International Nuclear Information System (INIS)

    1987-01-01

    On 27 May 1986 the Norwegian government appointed an inter-ministerial committee of senior officials to prepare a report on experiences in connection with the Chernobyl accident. The present second part of the committee's report describes proposals for measures to prevent and deal with similar accidents in the future. The committee's evaluations and proposals are grouped into four main sections: Safety and risk at nuclear power plants; the Norwegian contingency organization for dealing with nuclear accidents; compensation issues; and international cooperation

  9. I spy with my little eye - the detection of intentional contingency in early psychosis

    NARCIS (Netherlands)

    Fett, A.J.; Berdugo, C.I.G.; Hanssen, E.; Lemmers-Jansen, I.; Shergill, S.S.; Krabbendam, L.

    2015-01-01

    Introduction: Paranoid delusions have been associated with a tendency to over-attribute intentionality and contingency to others' actions and incidental events in individuals with chronic psychosis. However, this hyper-associative perception bias has not been investigated in the early illness stages

  10. Development of a new cause classification method considering plant ageing and human errors for adverse events which occurred in nuclear power plants and some results of its application

    International Nuclear Information System (INIS)

    Miyazaki, Takamasa

    2007-01-01

    The adverse events which occurred in nuclear power plants are analyzed to prevent similar events, and in the analysis of each event, the cause of the event is classified by a cause classification method. This paper shows a new cause classification method which is improved in several points as follows: (1) the whole causes are systematically classified into three major categories such as machine system, operation system and plant outside causes, (2) the causes of the operation system are classified into several management errors normally performed in a nuclear power plant, (3) the content of ageing is defined in detail for their further analysis, (4) human errors are divided and defined by the error stage, (5) human errors can be related to background factors, and so on. This new method is applied to the adverse events which occurred in domestic and overseas nuclear power plants in 2005. From these results, it is clarified that operation system errors account for about 60% of the whole causes, of which approximately 60% are maintenance errors, about 40% are worker's human errors, and that the prevention of maintenance errors, especially worker's human errors is crucial. (author)

  11. Derivation of working levels for animal feedstuffs for use in the event of a future nuclear accident

    International Nuclear Information System (INIS)

    Nisbet, A.; Woodman, R.; Brown, J.

    1998-04-01

    In the event of a future nuclear accident, European Council Food Intervention Levels (CFILs) would be legally binding for foodstuffs marketed in the UK. Practical guidance has been developed on the activity concentrations of radiocaesium and radiostrontium in animal feedstuffs that would give rise to concentrations equivalent to the relevant CFIL in the final animal product. The animals considered were dairy and beef cattle, lambs, pigs, broiler chickens and laying hens. Typical diets have been derived for each animal. The NRPB foodchain model FARMLAND has been used to predict activity concentrations in different feedstuffs for accidents occurring at different times of the year. The predicted concentrations were combined with the data on dietary composition, information on feed-to-product transfer and the relevant CFIL to estimate the corresponding Working levels in Animal Feedstuffs (WAFs). The calculations were carried out using a dedicated software system called SILAFOD. This flexible system can be used to carry out more specific assessments. A handbook that accompanies this report contains detailed information on animal diets, contributions from various feedstuffs to intakes of activity and the corresponding WAFs. The early phase after an accident and the longer-term phase are both considered. The work received partial financial support from the Ministry of Agriculture, Fisheries and Food, Radiological Safety and Nutrition Division. (author)

  12. Development of Emergency Operating Strategies for Beyond Design Basis External Event(BDBEE)s in Korean WH Nuclear Power Plants

    Energy Technology Data Exchange (ETDEWEB)

    Yoon, Duk-Joo; Lee, Seung-Chan; Sung, Je-Joong; Ha, Sang-Jun [KHNP CRI, Daejeon (Korea, Republic of); Hong, Soon-Joon; Hwang, Su-Hyun; Lee, Byung-Chul; Park, Kang-Min [FNC Tech. Co., Yongin (Korea, Republic of)

    2015-10-15

    Westinghouse developed and connected emergency operating procedures into a set of FLEX Support Guidelines(FSGs). This paper explains that Korean WH(Westinghouse) type nuclear power plants develop emergency operating strategies for ELAP(extended loss of all AC power), which include guidelines to use permanent and portable equipment as necessary to prevent core damage until AC power is restored from a reliable alternate source of AC power. The Korean emergency operating response strategies were developed to cope with a ELAP such as Fukushima event. The strategies include guidelines to prevent fuel damage using the FLEX equipment. Operators should take actions to prepare FLEX equipment within license basis SBO coping time. The loss of all AC power has been analyzed to identify the behavior of major NSSS process variables using RELAP computer code. The accident analysis showed that the plant does not result in fuel damage in 72 hours after an ELAP if operators take actions to cool RCS with opening of SG ADV in 5 gpm seal leak case. In this scenario, because ELAP is in process and all power cannot be used, operator should operate the FLEX equipment in order to actuate active equipment using the EOP fo SBO response. This strategy will prevent entering SAMG because this actions result in core cooling and stay in core exit temperature less than 650 .deg. C. Korean emergency operating guidelines(EOGs) will be developed using this strategies for response to the BDBEE.

  13. Undetected latent failures of safety-related systems. Preliminary survey of events in nuclear power plants 1980-1997

    International Nuclear Information System (INIS)

    Lydell, B.

    1998-03-01

    This report summarizes results and insights from a preliminary survey of events involving undetected, latent failures of safety-related systems. The survey was limited to events where mispositioned equipment (e.g., valves, switches) remained undetected, thus rendering standby equipment or systems unavailable for short or long time periods. Typically, these events were symptoms of underlying latent errors (e.g., design errors, procedure errors, unanalyzed safety conditions) and programmatic errors. The preliminary survey identified well over 300 events. Of these, 95 events are documented in this report. Events involving mispositioned equipment are commonplace. Most events are discovered soon after occurrence, however. But as evidenced by the survey results, some events remained undetected beyond several shift changes. The recommendations developed by the survey emphasize the importance of applying modern root cause analysis techniques to the event analysis to ensure that the causes and implications of occurred events are fully understood

  14. Development of synchronous VHL syndrome tumors reveals contingencies and constraints to tumor evolution

    DEFF Research Database (Denmark)

    Fisher, Rosalie; Horswell, Stuart; Rowan, Andrew

    2014-01-01

    are contingent upon the nature of 3p loss of heterozygosity occurring early in tumorigenesis. However, despite distinct 3p events, genomic, proteomic and immunohistochemical analyses reveal evidence for convergence upon the PI3K-AKT-mTOR signaling pathway. Four germline tumors in this young patient...... a germline VHL mutation, the evolutionary principles of contingency and convergence in tumor development are complementary. In this small set of patients with early stage VHL-associated tumors, there is reduced mutation burden and limited evidence of intra-tumor heterogeneity....

  15. Problems with Contingency Theory: Testing Assumptions Hidden within the Language of Contingency "Theory".

    Science.gov (United States)

    Schoonhoven, Clausia Bird

    1981-01-01

    Discusses problems in contingency theory, which relates organizational structure to the tasks performed and the information needed. Analysis of data from 17 hospitals suggests that traditional contingency theory underrepresents the complexity of relations among technological uncertainty, structure, and organizational effectiveness. (Author/RW)

  16. Optimal self-esteem is contingent: Intrinsic versus extrinsic and upward versus downward contingencies

    NARCIS (Netherlands)

    Vonk, R.; Smit, H.M.M.

    2012-01-01

    We argue that noncontingent, unconditional self-esteem is not optimal but defensive. We introduce the concept of intrinsic contingency, where self-esteem is affected by whether one's actions are self-congruent and conducive to personal growth. Whereas external contingencies, especially social and

  17. A System for the Feedback of Experience from Events in Nuclear Installations. Safety Guide (Spanish Edition); Un sistema de retroinformacion sobre la experiencia derivada de sucesos ocurridos en establecimientos nucleares. Guia de seguridad

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2012-07-15

    This Safety Guide provides recommendations on all the main components of operating experience feedback systems, utilizing relevant information on events and abnormal conditions that have occurred at nuclear installations around the world. It focuses on the interaction between the different systems for using operating experience feedback and constitutes an update and an extension of Part I, A National System, of Systems for Reporting Unusual Events in Nuclear Power Plants (IAEA Safety Series No. 93). Contents: 1. Introduction; 2. Main elements of a national system for the feedback of operational experience; 3. Screening of events; 4. Investigation and analysis of events; 5. Corrective actions; 6. Trending and review to recognize emergent problems; 7. Utilization, dissemination and exchange of information on operating experience; 8. Reviewing the effectiveness of the process for feedback of operational experience; 9. Quality assurance; 10. Reporting of safety related events; Appendix I: Reporting criteria and categories; Appendix II: Types of event report, timing, format and content; Appendix III: Investigation and analysis of events; Appendix IV: Approval and implementation of corrective actions; Annex I: Data management for the feedback of operating experience; Annex II: Example of elements of a national feedback system for operating experience.

  18. Flood control construction of Shidao Bay nuclear power plant and safety analysis for hypothetical accident of HTR-PM

    International Nuclear Information System (INIS)

    Chen Yongrong; Zhang Keke; Zhu Li

    2014-01-01

    A series of events triggered by tsunami eventually led to the Fukushima nuclear accident. For drawing lessons from the nuclear accident and applying to Shidao Bay nuclear power plant flood control construction, we compare with the state laws and regulations, and prove the design of Shidao Bay nuclear power plant flood construction. Through introducing the history of domestic tsunamis and the national researches before and after the Fukushima nuclear accident, we expound the tsunami hazards of Shidao Bay nuclear power plant. In addition, in order to verify the safety of HTR-PM, we anticipate the contingent accidents after ''superposition event of earthquake and extreme flood'', and analyse the abilities and measures of HTR-PM to deal with these beyond design basis accidents (BDBA). (author)

  19. Contingency Contractor Optimization Phase 3 Sustainment Software Design Document - Contingency Contractor Optimization Tool - Prototype

    Energy Technology Data Exchange (ETDEWEB)

    Durfee, Justin David; Frazier, Christopher Rawls; Bandlow, Alisa; Jones, Katherine A

    2016-05-01

    This document describes the final software design of the Contingency Contractor Optimization Tool - Prototype. Its purpose is to provide the overall architecture of the software and the logic behind this architecture. Documentation for the individual classes is provided in the application Javadoc. The Contingency Contractor Optimization project is intended to address Department of Defense mandates by delivering a centralized strategic planning tool that allows senior decision makers to quickly and accurately assess the impacts, risks, and mitigation strategies associated with utilizing contract support. The Contingency Contractor Optimization Tool - Prototype was developed in Phase 3 of the OSD ATL Contingency Contractor Optimization project to support strategic planning for contingency contractors. The planning tool uses a model to optimize the Total Force mix by minimizing the combined total costs for selected mission scenarios. The model optimizes the match of personnel types (military, DoD civilian, and contractors) and capabilities to meet mission requirements as effectively as possible, based on risk, cost, and other requirements.

  20. Comparative Study of Determining of the Responsible Person and the Basis of Compensation in Civil Liability Results from Events Related to Nuclear Facilities

    Directory of Open Access Journals (Sweden)

    Sayyed Mohammad Mahdi Qabuli Dorafshan

    2015-12-01

    Full Text Available Nuclear facilities, though have large advantages for human being, they also creates heavy hazards. Thus, the question of civil liability results from events of mentioned facilities are so significant. This paper studies the question of the basis and responsible for compensation results from aforementioned events in international instruments, Iran and French law. Outcome of this study shows that in this regard, Paris and Vienna conventions and the other related conventions and protocols adjust a special legal régime. In this respect, the international instruments while distancing themselves from liability based on fault, highlight the exclusive responsibility of the operator of nuclear facilities and they have commited the operator to insurance or appropriate secure financing. Also French legal régime have followed this manner with the impact of the Paris Convention and its amendments and additions. There is no special provisions in Iran legal régime in this matter so civil liability results from nuclear events is under general rules of civil liability and rules such Itlaf (loss, Tasbib (causation, Taqsir (fault and La-zarar (no damage in the context of Imamye jurisprudence. Ofcourse, the responsible is basically the one who the damage is attributable to him. Finaly, It is appropriate that the Iranian legislator predict favorable régime and provides special financial fund for compensation of possible injured parties in accordance with necessities and specific requirements related to nuclear energy

  1. Graded Approach to the Development of a Contingency Plan for On-Line Maintenance

    International Nuclear Information System (INIS)

    Chang, Hee Seung; Kim, Jung Wun; Song, Tae Young

    2012-01-01

    Many utilities perform preventive maintenance for safety systems during power operation to improve equipment reliability so as to focus on the work activities more easily and improve the quality of maintenance. Such a strategy can also reduce outage work activities, thus allowing resources to be utilized effectively. Preventive maintenance during power operation, known as on-line maintenance (OLM), requires an assessment and mitigation of risk, which can increase owing to out-of-service safety systems. One of the mitigation action plans is a contingency plan. EPRI recommends the development of a contingency plan for all planned system outages which include factors that strongly affect safety. The Korea Hydro and Nuclear Power Company (KHNP) undertook the preventive maintenance of the Essential Chilled Water System (ECWS) of a Westinghouse plant as a pilot OLM implementation. During the preparation of the work activities, a contingency plan was a pertinent issue during the discussions with regulators, especially regarding the scope and depth of the plan. This paper discusses the purpose of a contingency plan, including as examples some cases of US utilities, and proposes a graded approach to develop a contingency plan for OLM in consideration of the risks

  2. Nuclear fuel cycle facilities, laboratories, irradiators, particle accelerators, under-decommissioning reactors and radioactive waste management facilities safety. Lessons learned from events notified between 2005 and 2008

    International Nuclear Information System (INIS)

    2001-01-01

    Maintaining high levels of safety in nuclear facilities requires constant vigilance by everyone involved, especially by plant operators who are first and foremost responsible for safety in their facilities. Safety can never be taken for granted; constant efforts must be made to improve it, by taking new knowledge and available operating feedback into account. In this respect, a substantial part of operating feedback is made up of lessons learned from analysing events, incidents or accidents occurring in France or in similar facilities abroad. To encourage the diffusion of operating feedback, IRSN has produced a report concerning events notified to the Nuclear Safety Authority (ASN) by operators of LUDD facilities between 2005 and 2008. The main objective is to make general lessons for safety in this type of facility available based on a cross-disciplinary analysis of notified events and noted evolution trends. IRSN has had tools for managing information concerning events occurring in France and abroad for many years. These tools are used to analyse the events in order to take into account the relevant lessons learned in the safety assessments performed on behalf of ASN and also to define study and research programmes to maintain its expertise and expand its knowledge. The report has 4 sections: - the first section (chapters 2 to 4) presents the LUDD facilities so that the facilities themselves, their diversity and the main associated risks can be better understood. It also includes a brief reminder of plant operator obligations in notifying events and describes the database used by the Institute to manage the data relating to the notified events; - the second section (chapter 5) summarises the main changes noted in the events notified to ASN during 2005 to 2008 and provides an overall assessment of the consequences of these events for the environment, the population and the workers; - the third section (chapter 6) describes significant events occurring in France

  3. Color and Contingency in Robert Boyle's Works.

    Science.gov (United States)

    Baker, Tawrin

    2015-01-01

    This essay investigates the relationship between color and contingency in Robert Boyle's Experiments and Considerations Touching Colours (1664) and his essays on the unsuccessfulness of experiments in Certain Physiological Essays (1661). In these two works Boyle wrestles with a difficult practical and philosophical problem with experiments, which he calls the problem of contingency. In Touching Colours, the problem of contingency is magnified by the much-debated issue of whether color had any deep epistemic importance. His limited theoretical principle guiding him in Touching Colours, that color is but modified light, further exacerbated the problem. Rather than theory, Boyle often relied on craftsmen, whose mastery of color phenomena was, Boyle mentions, brought about by economic forces, to determine when colors were indicators of important 'inward' properties of substances, and thus to secure a solid foundation for his experimental history of color.

  4. Equivalence relations and the reinforcement contingency.

    Science.gov (United States)

    Sidman, M

    2000-07-01

    Where do equivalence relations come from? One possible answer is that they arise directly from the reinforcement contingency. That is to say, a reinforcement contingency produces two types of outcome: (a) 2-, 3-, 4-, 5-, or n-term units of analysis that are known, respectively, as operant reinforcement, simple discrimination, conditional discrimination, second-order conditional discrimination, and so on; and (b) equivalence relations that consist of ordered pairs of all positive elements that participate in the contingency. This conception of the origin of equivalence relations leads to a number of new and verifiable ways of conceptualizing equivalence relations and, more generally, the stimulus control of operant behavior. The theory is also capable of experimental disproof.

  5. Contingency learning in human fear conditioning involves the ventral striatum.

    Science.gov (United States)

    Klucken, Tim; Tabbert, Katharina; Schweckendiek, Jan; Merz, Christian Josef; Kagerer, Sabine; Vaitl, Dieter; Stark, Rudolf

    2009-11-01

    The ability to detect and learn contingencies between fearful stimuli and their predictive cues is an important capacity to cope with the environment. Contingency awareness refers to the ability to verbalize the relationships between conditioned and unconditioned stimuli. Although there is a heated debate about the influence of contingency awareness on conditioned fear responses, neural correlates behind the formation process of contingency awareness have gained only little attention in human fear conditioning. Recent animal studies indicate that the ventral striatum (VS) could be involved in this process, but in human studies the VS is mostly associated with positive emotions. To examine this question, we reanalyzed four recently published classical fear conditioning studies (n = 117) with respect to the VS at three distinct levels of contingency awareness: subjects, who did not learn the contingencies (unaware), subjects, who learned the contingencies during the experiment (learned aware) and subjects, who were informed about the contingencies in advance (instructed aware). The results showed significantly increased activations in the left and right VS in learned aware compared to unaware subjects. Interestingly, this activation pattern was only found in learned but not in instructed aware subjects. We assume that the VS is not involved when contingency awareness does not develop during conditioning or when contingency awareness is unambiguously induced already prior to conditioning. VS involvement seems to be important for the transition from a contingency unaware to a contingency aware state. Implications for fear conditioning models as well as for the contingency awareness debate are discussed.

  6. A contingency table approach to nonparametric testing

    CERN Document Server

    Rayner, JCW

    2000-01-01

    Most texts on nonparametric techniques concentrate on location and linear-linear (correlation) tests, with less emphasis on dispersion effects and linear-quadratic tests. Tests for higher moment effects are virtually ignored. Using a fresh approach, A Contingency Table Approach to Nonparametric Testing unifies and extends the popular, standard tests by linking them to tests based on models for data that can be presented in contingency tables.This approach unifies popular nonparametric statistical inference and makes the traditional, most commonly performed nonparametric analyses much more comp

  7. Estimating state-contingent production functions

    DEFF Research Database (Denmark)

    Rasmussen, Svend; Karantininis, Kostas

    The paper reviews the empirical problem of estimating state-contingent production functions. The major problem is that states of nature may not be registered and/or that the number of observation per state is low. Monte Carlo simulation is used to generate an artificial, uncertain production...... environment based on Cobb Douglas production functions with state-contingent parameters. The pa-rameters are subsequently estimated based on different sizes of samples using Generalized Least Squares and Generalized Maximum Entropy and the results are compared. It is concluded that Maximum Entropy may...

  8. The contingent valuation method: a review

    International Nuclear Information System (INIS)

    Venkatachalam, L.

    2004-01-01

    The contingent valuation method (CVM) is a simple, flexible nonmarket valuation method that is widely used in cost-benefit analysis and environmental impact assessment. However, this method is subject to severe criticism. The criticism revolves mainly around two aspects, namely, the validity and the reliability of the results, and the effects of various biases and errors. The major objective of this paper is to review the recent developments on measures to address the validity and reliability issues arising out of different kinds of biases/errors and other related empirical and methodological issues concerning contingent valuation method

  9. Application of process monitoring to anomaly detection in nuclear material processing systems via system-centric event interpretation of data from multiple sensors of varying reliability

    International Nuclear Information System (INIS)

    Garcia, Humberto E.; Simpson, Michael F.; Lin, Wen-Chiao; Carlson, Reed B.; Yoo, Tae-Sic

    2017-01-01

    Highlights: • Process monitoring can strengthen nuclear safeguards and material accountancy. • Assessment is conducted at a system-centric level to improve safeguards effectiveness. • Anomaly detection is improved by integrating process and operation relationships. • Decision making is benefited from using sensor and event sequence information. • Formal framework enables optimization of sensor and data processing resources. - Abstract: In this paper, we apply an advanced safeguards approach and associated methods for process monitoring to a hypothetical nuclear material processing system. The assessment regarding the state of the processing facility is conducted at a system-centric level formulated in a hybrid framework. This utilizes architecture for integrating both time- and event-driven data and analysis for decision making. While the time-driven layers of the proposed architecture encompass more traditional process monitoring methods based on time series data and analysis, the event-driven layers encompass operation monitoring methods based on discrete event data and analysis. By integrating process- and operation-related information and methodologies within a unified framework, the task of anomaly detection is greatly improved. This is because decision-making can benefit from not only known time-series relationships among measured signals but also from known event sequence relationships among generated events. This available knowledge at both time series and discrete event layers can then be effectively used to synthesize observation solutions that optimally balance sensor and data processing requirements. The application of the proposed approach is then implemented on an illustrative monitored system based on pyroprocessing and results are discussed.

  10. A fuzzy-based reliability approach to evaluate basic events of fault tree analysis for nuclear power plant probabilistic safety assessment

    International Nuclear Information System (INIS)

    Purba, Julwan Hendry

    2014-01-01

    Highlights: • We propose a fuzzy-based reliability approach to evaluate basic event reliabilities. • It implements the concepts of failure possibilities and fuzzy sets. • Experts evaluate basic event failure possibilities using qualitative words. • Triangular fuzzy numbers mathematically represent qualitative failure possibilities. • It is a very good alternative for conventional reliability approach. - Abstract: Fault tree analysis has been widely utilized as a tool for nuclear power plant probabilistic safety assessment. This analysis can be completed only if all basic events of the system fault tree have their quantitative failure rates or failure probabilities. However, it is difficult to obtain those failure data due to insufficient data, environment changing or new components. This study proposes a fuzzy-based reliability approach to evaluate basic events of system fault trees whose failure precise probability distributions of their lifetime to failures are not available. It applies the concept of failure possibilities to qualitatively evaluate basic events and the concept of fuzzy sets to quantitatively represent the corresponding failure possibilities. To demonstrate the feasibility and the effectiveness of the proposed approach, the actual basic event failure probabilities collected from the operational experiences of the David–Besse design of the Babcock and Wilcox reactor protection system fault tree are used to benchmark the failure probabilities generated by the proposed approach. The results confirm that the proposed fuzzy-based reliability approach arises as a suitable alternative for the conventional probabilistic reliability approach when basic events do not have the corresponding quantitative historical failure data for determining their reliability characteristics. Hence, it overcomes the limitation of the conventional fault tree analysis for nuclear power plant probabilistic safety assessment

  11. Constructing a Model for Safe Nuclear Energy. General Conference Event to Focus on Innovative Cross-cutting Approach to Nuclear Safety

    International Nuclear Information System (INIS)

    Verlini, Giovanni

    2011-01-01

    Two innovative IAEA Extra-Budgetary Programmes, supporting safe nuclear energy in Bulgaria and Romania, passed their one-year milestone in 2010. Funded by the Norwegian government, these programmes are unique in that they cover separate but cross-cutting issues related to nuclear safety, including safety culture, safety assessments, risk management and resource management.

  12. Nuclear security in major public events: the XV Pan American Games and the III Para-Pan American Games in Brazil

    International Nuclear Information System (INIS)

    Mello, Luiz A. de; Monteiro Filho, Joselio S.; Belem, Lilia M.J.; Torres, Luiz F.B.

    2009-01-01

    The organization of a major public event involving large numbers of spectators and participants, presents important security challenges. Taking this into consideration, the Brazilian Nuclear Energy Commission (CNEN) has been requested, by the National Secretary of Public Security/ Ministry of Justice (SENASP/MJ), by the end of 2006, to participate on the security actions to be implemented in both the XV Pan American Games and III Para Pan American Games. The XV Pan American Games 2007 and the III Para Pan American Games were held in Rio de Janeiro, Brazil from 13 to 29 July 2007 and from 12 to 19 August 2007, respectively. Those events had 8700 participants between athletes, coaches and referees from 42 countries. More than 300 competition events were held at 17 different venues and were covered by 4910 professionals from TV, radio and written press. Around 2 million tickets have been sold or distributed and 18,000 volunteers participated on the organization. The participation of CNEN was concentrated on the implementation of specific nuclear and radiological security measures to be applied at those events. This was part of a multi-institutional plan for the security of the Games, coordinated by the National Secretary of Public Security of the Ministry of Justice (SENASP/MJ). The support provided by IAEA under a Cooperation Arrangement with the Brazilian authorities was a key factor for the success of the whole operation. The actions taken and the lessons identified by the Brazilian Nuclear Energy Commission related to nuclear and radiological security for the Pan American Games and for the Para Pan American Games are presented. (author)

  13. Synthesis of public authorities organisation in case of emergency and in a post-event situation (following a nuclear accident or a radiological attack) in France and abroad

    International Nuclear Information System (INIS)

    Kayser, O.

    2010-01-01

    After having briefly recalled how an emergency situation (notably in case of nuclear accident or radiological attack) is taken into account in the organisation of public authorities through specific plans (PPI or plans particuliers d'intervention, intervention specific plans), this report also describes how the situation is handled by these authorities after the end of the emergency situation (i.e. when the risk of new radioactive releases is over). This post-event stage is split into two phases: a transition phase which lasts several weeks or months, and a long term consequence management phase (over months or years). The author first describes the specificities of a nuclear or radiological event (accident or attack). He recalls the global public organisation and the involved actors. For the post-event period, he indicates the various actions, describes the interdepartmental coordination and the various aspects of the program designed to manage accident consequences on the long term. He also describes the roles of permanent bodies, agencies and institutes (ASN, ASND, MSNR, IRSN, INVS, ADEME, AFSSA, Meteo France, CEA, ANDRA, AREVA, EDF, ministries). The last part describes the action of public authorities in case of a nuclear accident occurring abroad. This includes relationship with European and international bodies

  14. Undetected latent failures of safety-related systems. Preliminary survey of events in nuclear power plants 1980-1997

    Energy Technology Data Exchange (ETDEWEB)

    Lydell, B. [RSA Technologies, Vista, CA (United States)

    1998-03-01

    This report summarizes results and insights from a preliminary survey of events involving undetected, latent failures of safety-related systems. The survey was limited to events where mispositioned equipment (e.g., valves, switches) remained undetected, thus rendering standby equipment or systems unavailable for short or long time periods. Typically, these events were symptoms of underlying latent errors (e.g., design errors, procedure errors, unanalyzed safety conditions) and programmatic errors. The preliminary survey identified well over 300 events. Of these, 95 events are documented in this report. Events involving mispositioned equipment are commonplace. Most events are discovered soon after occurrence, however. But as evidenced by the survey results, some events remained undetected beyond several shift changes. The recommendations developed by the survey emphasize the importance of applying modern root cause analysis techniques to the event analysis to ensure that the causes and implications of occurred events are fully understood. 7 refs, 4 tabs, 3 figs. Also available at the SKI Home page: //www.ski.se.

  15. Analyzing Contingency Contracting Purchases for Operation Iraqi Freedom (Unrestricted Version)

    National Research Council Canada - National Science Library

    Baldwin, Laura H; Ausink, John A; Campbell, Nancy F; Drew, John G; Roll, Jr, Charles R

    2008-01-01

    ...) in an effort to determine the size and extent of contractor support, and how plans for and the organization and execution of contingency contracting activities might be improved so that Contingency...

  16. Effectiveness evaluation of contingency sum as a risk management ...

    African Journals Online (AJOL)

    Ethiopian Journal of Environmental Studies and Management ... manage risks prone projects have adopted several methods, one of which is contingency sum. ... initial project cost, cost overrun and percentage allowed for contingency.

  17. 48 CFR 1632.770 - Contingency reserve payments.

    Science.gov (United States)

    2010-10-01

    ... FINANCING Contract Funding 1632.770 Contingency reserve payments. (a) Payments from the contingency reserve... advise the carrier of its decision. However, OPM shall not unreasonably withhold approval for amounts...

  18. Objective and Essential Elements of a State's Nuclear Security Regime. Nuclear Security Fundamentals (Chinese Edition)

    International Nuclear Information System (INIS)

    2014-01-01

    The possibility that nuclear material or other radioactive material could be used for criminal purposes or intentionally used in an unauthorized manner cannot be ruled out in the current global situation. States have responded to this risk by engaging in a collective commitment to strengthen the protection and control of such material and to respond effectively to nuclear security events. States have agreed to strengthen existing instruments and have established new international legal instruments to enhance nuclear security worldwide. Nuclear security is fundamental in the management of nuclear technologies and in applications where nuclear material or other radioactive material is used or transported. Through its nuclear security programme, the IAEA supports States to establish, maintain and sustain an effective nuclear security regime. The IAEA has adopted a comprehensive approach to nuclear security. This recognizes that an effective national nuclear security regime builds on: the implementation of relevant international legal instruments; information protection; physical protection; material accounting and control; detection of and response to trafficking in such material; national response plans; and contingency measures. With its Nuclear Security Series, the IAEA aims to assist States in implementing and sustaining such a regime in a coherent and integrated manner. The IAEA Nuclear Security Series comprises: Nuclear Security Fundamentals, which include the objective and essential elements of a State's nuclear security regime; Recommendations; Implementing Guides; and Technical Guidance. Each State carries the full responsibility for nuclear security. Specifically, each State has the responsibility to provide for the security of nuclear material and other radioactive material and their associated facilities and activities; to ensure the security of such material in use, storage, or in transport; to combat illicit trafficking and the inadvertent movement of

  19. Objective and Essential Elements of a State's Nuclear Security Regime. Nuclear Security Fundamentals (Arabic Edition)

    International Nuclear Information System (INIS)

    2014-01-01

    The possibility that nuclear material or other radioactive material could be used for criminal purposes or intentionally used in an unauthorized manner cannot be ruled out in the current global situation. States have responded to this risk by engaging in a collective commitment to strengthen the protection and control of such material and to respond effectively to nuclear security events. States have agreed to strengthen existing instruments and have established new international legal instruments to enhance nuclear security worldwide. Nuclear security is fundamental in the management of nuclear technologies and in applications where nuclear material or other radioactive material is used or transported. Through its nuclear security programme, the IAEA supports States to establish, maintain and sustain an effective nuclear security regime. The IAEA has adopted a comprehensive approach to nuclear security. This recognizes that an effective national nuclear security regime builds on: the implementation of relevant international legal instruments; information protection; physical protection; material accounting and control; detection of and response to trafficking in such material; national response plans; and contingency measures. With its Nuclear Security Series, the IAEA aims to assist States in implementing and sustaining such a regime in a coherent and integrated manner. The IAEA Nuclear Security Series comprises: Nuclear Security Fundamentals, which include the objective and essential elements of a State's nuclear security regime; Recommendations; Implementing Guides; and Technical Guidance. Each State carries the full responsibility for nuclear security. Specifically, each State has the responsibility to provide for the security of nuclear material and other radioactive material and their associated facilities and activities; to ensure the security of such material in use, storage, or in transport; to combat illicit trafficking and the inadvertent movement of

  20. Objective and Essential Elements of a State's Nuclear Security Regime. Nuclear Security Fundamentals

    International Nuclear Information System (INIS)

    2013-01-01

    The possibility that nuclear material or other radioactive material could be used for criminal purposes or intentionally used in an unauthorized manner cannot be ruled out in the current global situation. States have responded to this risk by engaging in a collective commitment to strengthen the protection and control of such material and to respond effectively to nuclear security events. States have agreed to strengthen existing instruments and have established new international legal instruments to enhance nuclear security worldwide. Nuclear security is fundamental in the management of nuclear technologies and in applications where nuclear material or other radioactive material is used or transported. Through its nuclear security programme, the IAEA supports States to establish, maintain and sustain an effective nuclear security regime. The IAEA has adopted a comprehensive approach to nuclear security. This recognizes that an effective national nuclear security regime builds on: the implementation of relevant international legal instruments; information protection; physical protection; material accounting and control; detection of and response to trafficking in such material; national response plans; and contingency measures. With its Nuclear Security Series, the IAEA aims to assist States in implementing and sustaining such a regime in a coherent and integrated manner. The IAEA Nuclear Security Series comprises: Nuclear Security Fundamentals, which include the objective and essential elements of a State's nuclear security regime; Recommendations; Implementing Guides; and Technical Guidance. Each State carries the full responsibility for nuclear security. Specifically, each State has the responsibility to provide for the security of nuclear material and other radioactive material and their associated facilities and activities; to ensure the security of such material in use, storage, or in transport; to combat illicit trafficking and the inadvertent movement of

  1. Objective and Essential Elements of a State's Nuclear Security Regime. Nuclear Security Fundamentals (Spanish Edition)

    International Nuclear Information System (INIS)

    2014-01-01

    The possibility that nuclear material or other radioactive material could be used for criminal purposes or intentionally used in an unauthorized manner cannot be ruled out in the current global situation. States have responded to this risk by engaging in a collective commitment to strengthen the protection and control of such material and to respond effectively to nuclear security events. States have agreed to strengthen existing instruments and have established new international legal instruments to enhance nuclear security worldwide. Nuclear security is fundamental in the management of nuclear technologies and in applications where nuclear material or other radioactive material is used or transported. Through its nuclear security programme, the IAEA supports States to establish, maintain and sustain an effective nuclear security regime. The IAEA has adopted a comprehensive approach to nuclear security. This recognizes that an effective national nuclear security regime builds on: the implementation of relevant international legal instruments; information protection; physical protection; material accounting and control; detection of and response to trafficking in such material; national response plans; and contingency measures. With its Nuclear Security Series, the IAEA aims to assist States in implementing and sustaining such a regime in a coherent and integrated manner. The IAEA Nuclear Security Series comprises: Nuclear Security Fundamentals, which include the objeurity Fundamentals, which include the objective and essential elements of a State's nuclear security regime; Recommendations; Implementing Guides; and Technical Guidance. Each State carries the full responsibility for nuclear security. Specifically, each State has the responsibility to provide for the security of nuclear material and other radioactive material and their associated facilities and activities; to ensure the security of such material in use, storage, or in transport; to combat illicit

  2. Objective and Essential Elements of a State's Nuclear Security Regime. Nuclear Security Fundamentals (French Edition)

    International Nuclear Information System (INIS)

    2014-01-01

    The possibility that nuclear material or other radioactive material could be used for criminal purposes or intentionally used in an unauthorized manner cannot be ruled out in the current global situation. States have responded to this risk by engaging in a collective commitment to strengthen the protection and control of such material and to respond effectively to nuclear security events. States have agreed to strengthen existing instruments and have established new international legal instruments to enhance nuclear security worldwide. Nuclear security is fundamental in the management of nuclear technologies and in applications where nuclear material or other radioactive material is used or transported. Through its nuclear security programme, the IAEA supports States to establish, maintain and sustain an effective nuclear security regime. The IAEA has adopted a comprehensive approach to nuclear security. This recognizes that an effective national nuclear security regime builds on: the implementation of relevant international legal instruments; information protection; physical protection; material accounting and control; detection of and response to trafficking in such material; national response plans; and contingency measures. With its Nuclear Security Series, the IAEA aims to assist States in implementing and sustaining such a regime in a coherent and integrated manner. The IAEA Nuclear Security Series comprises: Nuclear Security Fundamentals, which include the objective and essential elements of a State's nuclear security regime; Recommendations; Implementing Guides; and Technical Guidance. Each State carries the full responsibility for nuclear security. Specifically, each State has the responsibility to provide for the security of nuclear material and other radioactive material and their associated facilities and activities; to ensure the security of such material in use, storage, or in transport; to combat illicit trafficking and the inadvertent movement of

  3. Contingency Management with Human Autonomy Teaming

    Science.gov (United States)

    Shively, Robert J.; Lachter, Joel B.

    2018-01-01

    Automation is playing an increasingly important role in many operations. It is often cheaper faster and more precise than human operators. However, automation is not perfect. There are many situations in which a human operator must step in. We refer to these instances as contingencies and the act of stepping in contingency management. Here we propose coupling Human Autonomy Teaming (HAT) with contingency management. We describe two aspects to HAT, bi-directional communication, and working agreements (or plays). Bi-directional communication like Crew Resource Management in traditional aviation, allows all parties to contribute to a decision. Working agreements specify roles and responsibilities. Importantly working agreements allow for the possibility of roles and responsibilities changing depending on environmental factors (e.g., situations the automation was not designed for, workload, risk, or trust). This allows for the automation to "automatically" become more autonomous as it becomes more trusted and/or it is updated to deal with a more complete set of possible situations. We present a concrete example using a prototype contingency management station one might find in a future airline operations center. Automation proposes reroutes for aircraft that encounter bad weather or are forced to divert for environmental or systems reasons. If specific conditions are met, these recommendations may be autonomously datalinked to the affected aircraft.

  4. Thomas Aquinas on Contingency of Nature

    Czech Academy of Sciences Publication Activity Database

    Dvořák, Petr

    2008-01-01

    Roč. 5, č. 2 (2008), s. 185-196 ISSN 1214-8407 R&D Projects: GA AV ČR(CZ) IAA900090602 Institutional research plan: CEZ:AV0Z90090514 Keywords : Thomas Aquinas * determinism * contingency Subject RIV: AA - Philosophy ; Religion

  5. Two psychologies: Cognitive versus contingency-oriented

    NARCIS (Netherlands)

    Mey, H.R.A. De

    2003-01-01

    Cognitive psychology and contingency-based behavior analysis are contrasted to each other with respect to their philosophical and theoretical underpinnings as well as to theirpractical goals. Whereas the former focuses on intra-organismic structure and function in explaining minds, the latter

  6. Management issues regarding the contingent workforce

    Energy Technology Data Exchange (ETDEWEB)

    Bowen-Smed, S. [Bowen Workforce Solutions, Calgary, AB (Canada)

    2004-07-01

    Fifty per cent of corporate leaders in Calgary today will be eligible for retirement over the next 5 years. In addition, 53 per cent of the entire Calgary workforce is 45 years or older. This paper suggests that only companies that seek aggressive programs to engage immigrants and contractors will weather the skills shortages anticipated in the future. It was noted that contractors care about aligning values to organizations, regardless of the project length, and that professional development is a key consideration when it comes to selecting their next project. Contingent workforce issues include: effectiveness; classification; risk; and cost. It was stated that effectiveness of the contingent workforce is an employer's responsibility. Factors that would strengthen the relationship between corporations and contractors include: proper orientation to manage expectations; training to improve productivity; tracking to enhance the quality of the workforce; and a management process to ensure adherence to protocol. It was concluded that the contingent workforce is an essential component to human capital management strategy, but that key issues must be managed to avoid unnecessary costs. In addition, effectiveness improves when processes are implemented. It was also suggested that technology is an essential component of the solution. Outsourcing is an effective approach to managing the contingent workforce. tabs., figs.

  7. Contingency learning in alcohol dependence and pathological gambling: learning and unlearning reward contingencies

    NARCIS (Netherlands)

    Vanes, Lucy D.; van Holst, Ruth J.; Jansen, Jochem M.; van den Brink, Wim; Oosterlaan, Jaap; Goudriaan, Anna E.

    2014-01-01

    Patients with alcohol dependence (AD) and pathological gambling (PG) are characterized by dysfunctional reward processing and their ability to adapt to alterations of reward contingencies is impaired. However, most neurocognitive tasks investigating reward processing involve a complex mix of

  8. Contingency learning in alcohol dependence and pathological gambling: learning and unlearning reward contingencies

    NARCIS (Netherlands)

    Vanes, L.D.; Holst, R.J. van; Jansen, J.M.; Brink, W. van den; Oosterlaan, J.; Goudriaan, A.E.

    2014-01-01

    BACKGROUND: Patients with alcohol dependence (AD) and pathological gambling (PG) are characterized by dysfunctional reward processing and their ability to adapt to alterations of reward contingencies is impaired. However, most neurocognitive tasks investigating reward processing involve a complex

  9. Contingency Learning in Alcohol Dependence and Pathological Gambling: Learning and Unlearning Reward Contingencies

    NARCIS (Netherlands)

    Vanes, L.D.; Holst, R.; Jansen, J.D.; van den Brink, W.A.; Oosterlaan, J.; Goudriaan, A.E.

    2014-01-01

    Background: Patients with alcohol dependence (AD) and pathological gambling (PG) are characterized by dysfunctional reward processing and their ability to adapt to alterations of reward contingencies is impaired. However, most neurocognitive tasks investigating reward processing involve a complex

  10. Contingency Contractor Optimization Phase 3 Sustainment Third-Party Software List - Contingency Contractor Optimization Tool - Prototype

    Energy Technology Data Exchange (ETDEWEB)

    Durfee, Justin David; Frazier, Christopher Rawls; Bandlow, Alisa

    2016-05-01

    The Contingency Contractor Optimization Tool - Prototype (CCOT-P) requires several third-party software packages. These are documented below for each of the CCOT-P elements: client, web server, database server, solver, web application and polling application.

  11. Policy elements for post-accident management in the event of nuclear accident. Document drawn up by the Steering Committee for the Management of the Post-Accident Phase of a Nuclear Accident (CODIRPA). Final version - 5 October 2012

    International Nuclear Information System (INIS)

    2012-01-01

    Pursuant to the Inter-ministerial Directive on the Action of the Public Authorities, dated 7 April 2005, in the face of an event triggering a radiological emergency, the National directorate on nuclear safety and radiation protection (DGSNR), which became the Nuclear safety authority (ASN) in 2006, was tasked with working the relevant Ministerial offices in order to set out the framework and outline, prepare and implement the provisions needed to address post-accident situations arising from a nuclear accident. In June 2005, the ASN set up a Steering committee for the management of the post-accident phase in the event of nuclear accident or a radiological emergency situation (CODIRPA), put in charge of drafting the related policy elements. To carry out its work, CODIRPA set up a number of thematic working groups from 2005 on, involving in total several hundred experts from different backgrounds (local information commissions, associations, elected officials, health agencies, expertise agencies, authorities, etc.). The working groups reports have been published by the ASN. Experiments on the policy elements under construction were carried out at the local level in 2010 across three nuclear sites and several of the neighbouring municipalities, as well as during national crisis drills conducted since 2008. These works gave rise to two international conferences organised by ASN in 2007 and 2011. The policy elements prepared by CODIRPA were drafted in regard to nuclear accidents of medium scale causing short-term radioactive release (less than 24 hours) that might occur at French nuclear facilities equipped with a special intervention plan (PPI). They also apply to actions to be carried out in the event of accidents during the transport of radioactive materials. Following definitions of each stage of a nuclear accident, this document lists the principles selected by CODIRPA to support management efforts subsequent to a nuclear accident. Then, it presents the main

  12. 40 CFR 51.1012 - Requirement for contingency measures.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 2 2010-07-01 2010-07-01 false Requirement for contingency measures... Implementation of PM2.5 National Ambient Air Quality Standards § 51.1012 Requirement for contingency measures... contingency measures to be undertaken if the area fails to make reasonable further progress, or fails to...

  13. 40 CFR 264.227 - Emergency repairs; contingency plans.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 25 2010-07-01 2010-07-01 false Emergency repairs; contingency plans... FACILITIES Surface Impoundments § 264.227 Emergency repairs; contingency plans. (a) A surface impoundment... days after detecting the problem. (c) As part of the contingency plan required in subpart D of this...

  14. 78 FR 46781 - Federal Acquisition Regulation; Definition of Contingency Operation

    Science.gov (United States)

    2013-08-01

    ... Federal Acquisition Regulation; Definition of Contingency Operation AGENCY: Department of Defense (DoD... the Federal Acquisition Regulation (FAR) to revise the definition of ``contingency operation'' to... ``contingency operation'' at FAR 2.101 in accordance with the statutory change to the definition made by...

  15. 30 CFR 218.152 - Fishermen's Contingency Fund.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 2 2010-07-01 2010-07-01 false Fishermen's Contingency Fund. 218.152 Section 218.152 Mineral Resources MINERALS MANAGEMENT SERVICE, DEPARTMENT OF THE INTERIOR MINERALS REVENUE..., Offshore § 218.152 Fishermen's Contingency Fund. Upon the establishment of the Fishermen's Contingency Fund...

  16. 78 FR 13765 - Federal Acquisition Regulation; Definition of Contingency Operation

    Science.gov (United States)

    2013-02-28

    ... Federal Acquisition Regulation; Definition of Contingency Operation AGENCY: Department of Defense (DoD... Regulation (FAR) to revise the definition of ``contingency operation'' to address the statutory change to the... ``contingency operation'' at FAR 2.101 in accordance with the statutory change to the definition made by...

  17. 10 CFR 72.184 - Safeguards contingency plan.

    Science.gov (United States)

    2010-01-01

    ... 10 Energy 2 2010-01-01 2010-01-01 false Safeguards contingency plan. 72.184 Section 72.184 Energy... Protection § 72.184 Safeguards contingency plan. (a) The requirements of the licensee's safeguards contingency plan for responding to threats and radiological sabotage must be as defined in appendix C to part...

  18. 50 CFR 296.3 - Fishermen's contingency fund.

    Science.gov (United States)

    2010-10-01

    ... 50 Wildlife and Fisheries 7 2010-10-01 2010-10-01 false Fishermen's contingency fund. 296.3... ADMINISTRATION, DEPARTMENT OF COMMERCE CONTINENTAL SHELF FISHERMEN'S CONTINGENCY FUND § 296.3 Fishermen's contingency fund. (a) General. There is established in the Treasury of the United States the Fishermen's...

  19. Psychophysics of associative learning: Quantitative properties of subjective contingency.

    Science.gov (United States)

    Maia, Susana; Lefèvre, Françoise; Jozefowiez, Jérémie

    2018-01-01

    Allan and collaborators (Allan, Hannah, Crump, & Siegel, 2008; Allan, Siegel, & Tangen, 2005; Siegel, Allan, Hannah, & Crump, 2009) recently proposed to apply signal detection theory to the analysis of contingency judgment tasks. When exposed to a flow of stimuli, participants are asked to judge whether there is a contingent relation between a cue and an outcome, that is, whether the subjective cue-outcome contingency exceeds a decision threshold. In this context, we tested the following hypotheses regarding the relation between objective and subjective cue-outcome contingency: (a) The underlying distributions of subjective cue-outcome contingency are Gaussian; (b) The mean distribution of subjective contingency is a linear function of objective cue-outcome contingency; and (c) The variance in the distribution of subjective contingency is constant. The hypotheses were tested by combining a streamed-trial contingency assessment task with a confidence rating procedure. Participants were exposed to rapid flows of stimuli at the end of which they had to judge whether an outcome was more (Experiment 1) or less (Experiment 2) likely to appear following a cue and how sure they were of their judgment. We found that although Hypothesis A seems reasonable, Hypotheses B and C were not. Regarding Hypothesis B, participants were more sensitive to positive than to negative contingencies. Regarding Hypothesis C, the perceived cue-outcome contingency became more variable when the contingency became more positive or negative, but only to a slight extent. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

  20. 48 CFR 225.7303-4 - Contingent fees.

    Science.gov (United States)

    2010-10-01

    ... 48 Federal Acquisition Regulations System 3 2010-10-01 2010-10-01 false Contingent fees. 225.7303....7303-4 Contingent fees. (a) Except as provided in paragraph (b) of this subsection, contingent fees are generally allowable under DoD contracts, provided— (1) The fees are paid to a bona fide employee or a bona...

  1. Sartre's Contingency of Being and Asouzu's Principle of Causality ...

    African Journals Online (AJOL)

    The position of this work is that all contingent beings have a causal agent. This position is taken as a result of trying to delve into the issue of contingency and causality of being which has been discussed by many philosophers of diverse epochs of philosophy. This work tries to participate in the debate of whether contingent ...

  2. Computer Security at Nuclear Facilities (French Edition)

    International Nuclear Information System (INIS)

    2013-01-01

    The possibility that nuclear or other radioactive material could be used for malicious purposes cannot be ruled out in the current global situation. States have responded to this risk by engaging in a collective commitment to strengthen the protection and control of such material and to respond effectively to nuclear security events. States have agreed to strengthen existing instruments and have established new international legal instruments to enhance nuclear security worldwide. Nuclear security is fundamental in the management of nuclear technologies and in applications where nuclear or other radioactive material is used or transported. Through its Nuclear Security Programme, the IAEA supports States to establish, maintain and sustain an effective nuclear security regime. The IAEA has adopted a comprehensive approach to nuclear security. This recognizes that an effective national nuclear security regime builds on: the implementation of relevant international legal instruments; information protection; physical protection; material accounting and control; detection of and response to trafficking in such material; national response plans; and contingency measures. With its Nuclear Security Series, the IAEA aims to assist States in implementing and sustaining such a regime in a coherent and integrated manner. The IAEA Nuclear Security Series comprises Nuclear Security Fundamentals, which include objectives and essential elements of a State's nuclear security regime; Recommendations; Implementing Guides; and Technical Guidance. Each State carries the full responsibility for nuclear security, specifically: to provide for the security of nuclear and other radioactive material and associated facilities and activities; to ensure the security of such material in use, storage or in transport; to combat illicit trafficking and the inadvertent movement of such material; and to be prepared to respond to a nuclear security event. This publication is in the Technical Guidance

  3. Contingent capture effects in temporal order judgments.

    Science.gov (United States)

    Born, Sabine; Kerzel, Dirk; Pratt, Jay

    2015-08-01

    The contingent attentional capture hypothesis proposes that visual stimuli that do not possess characteristics relevant for the current task will not capture attention, irrespective of their bottom-up saliency. Typically, contingent capture is tested in a spatial cuing paradigm, comparing manual reaction times (RTs) across different conditions. However, attention may act through several mechanisms and RTs may not be ideal to disentangle those different components. In 3 experiments, we examined whether color singleton cues provoke cuing effects in temporal order judgments (TOJs) and whether they would be contingent on attentional control sets. Experiment 1 showed that color singleton cues indeed produce cuing effects in TOJs, even in a cluttered and dynamic target display containing multiple heterogeneous distractors. In Experiment 2, consistent with contingent capture, we observed reliable cuing effects only when the singleton cue matched participants' current attentional control set. Experiment 3 suggests that a sensory interaction account of the differences found in Experiment 2 is unlikely. Our results help to discern the attentional components that may play a role in contingent capture. Further, we discuss a number of other effects (e.g., reversed cuing effects) that are found in RTs, but so far have not been reported in TOJs. Those differences suggest that RTs are influenced by a multitude of mechanisms; however, not all of these mechanisms may affect TOJs. We conclude by highlighting how the study of attentional capture in TOJs provides valuable insights for the attention literature, but also for studies concerned with the perceived timing between stimuli. (c) 2015 APA, all rights reserved).

  4. Survey of reportable events in nuclear power plants in the Federal Republic of Germany. Period covered: 2nd quarter 1994

    International Nuclear Information System (INIS)

    1994-01-01

    There were 40 reportable events in the period covered. 39 events belonged to the lowest reporting category N (normal notification, INES scale 0), 1 incident belongs to the category E (immediate notification, INES scale 1). There was no release above limit of radioactivity nor were there any effects on man or environment. (orig.) [de

  5. The Role of the Rat Medial Prefrontal Cortex in Adapting to Changes in Instrumental Contingency

    Science.gov (United States)

    Coutureau, Etienne; Esclassan, Frederic; Di Scala, Georges; Marchand, Alain R.

    2012-01-01

    In order to select actions appropriate to current needs, a subject must identify relationships between actions and events. Control over the environment is determined by the degree to which action consequences can be predicted, as described by action-outcome contingencies – i.e. performing an action should affect the probability of the outcome. We evaluated in a first experiment adaptation to contingency changes in rats with neurotoxic lesions of the medial prefrontal cortex. Results indicate that this brain region is not critical to adjust instrumental responding to a negative contingency where the rats must refrain from pressing a lever, as this action prevents reward delivery. By contrast, this brain region is required to reduce responding in a non-contingent situation where the same number of rewards is freely delivered and actions do not affect the outcome any more. In a second experiment, we determined that this effect does not result from a different perception of temporal relationships between actions and outcomes since lesioned rats adapted normally to gradually increasing delays in reward delivery. These data indicate that the medial prefrontal cortex is not directly involved in evaluating the correlation between action-and reward-rates or in the perception of reward delays. The deficit in lesioned rats appears to consist of an abnormal response to the balance between contingent and non-contingent rewards. By highlighting the role of prefrontal regions in adapting to the causal status of actions, these data contribute to our understanding of the neural basis of choice tasks. PMID:22496747

  6. Modes of relating to contingency: An exploration of experiences in advanced cancer patients.

    Science.gov (United States)

    Kruizinga, Renske; Hartog, Iris D; Scherer-Rath, Michael; Schilderman, Hans; Van Laarhoven, Hanneke

    2017-08-01

    Throughout their lives, people are confronted with unexpected life events, which can be difficult to incorporate into their life narratives. Such a confrontation can result in an experience of contingency. Different ways of relating to contingency have been described by Wuchterl: denying, acknowledging, and "encounter with the Other." In the present article, we aim to trace these theoretical distinctions in real-life experiences of patients. We analyzed 45 interviews using the constant comparative method with a directed content analysis approach in the Atlas.ti coding program. The interviews originated from a randomized controlled trial evaluating an assisted reflection on life events and ultimate life goals. Seven spiritual counselors from six hospitals in the Netherlands conducted the interviews from July of 2014 to March of 2016. All 45 patients had advanced cancer. We found four different modes into which relating to contingency can be classified: denying, acknowledging, accepting, and receiving. With denying, patients did not mention any impact of the life event on their lives. In acknowledging, the impact was recognized and a start was made to incorporate the event into their life. In accepting, patients went through a process of reinterpretation of the event. In receiving, patients talked about receiving insights from their illness and living a more conscious life. Our study is the first to investigate the different ways of relating to contingency in clinical practice. The defined modes will improve our understanding of the various ways in which cancer patients relate to their disease, allowing caregivers to better target and shape individual care.

  7. IPEEE review of external events of the Asco I nuclear plant; Revision del IPEEE de sucesos externos de la Central Nuclear Asco I

    Energy Technology Data Exchange (ETDEWEB)

    Aleman, A.; Canadell, F.; Beltran, F.; Pifarre, D.; Hernandez, H.; Gasca, C.

    2012-07-01

    During the risk analysis update of Asco PP (2010), it has been carried out a review of the vulnerabilities against severe accidents caused by external events (individual Plant Examination of external Events, IPEEE). The assessment has included analysis of accidents in industrial and military facilities nearby and transportation accidents (i.e., rail, road and aircraft impact) release of hazardous materials on site, external flooding, turbine missiles and strong winds. (Author)

  8. Yampa River Valley sub-area contingency plan

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1998-08-01

    The Yampa River Valley sub-area contingency plan (Contingency Plan) has been prepared for two counties in northwestern Colorado: Moffat County and Routt County. The Contingency Plan is provided in two parts, the Contingency Plan and the Emergency Response Action Plan (ERAP). The Contingency Plan provides information that should be helpful in planning to minimize the impact of an oil spill or hazardous material incident. It contains discussions of planning and response role, hazards identification, vulnerability analysis, risk analysis, cleanup, cost recovery, training, and health and safety. It includes information on the incident command system, notifications, response capabilities, emergency response organizations, evacuation and shelter-in-place, and immediate actions.

  9. An overview of the insurance of nuclear power plants

    International Nuclear Information System (INIS)

    Tannion, T.

    2011-01-01

    Insurance is the transfer of financial risk. It is used to offset losses on the happening of a contingent and uncertain event. It is, in effect, the transfer of the financial risk of a loss, from one entity to another, in exchange for the payment of a premium. In the interest of brevity, this paper does not address the issue of civil liabilities applying to the operation of nuclear power plants and arising out of the Paris or Vienna Conventions or any of the protocols thereto. For detailed information on these, please refer to the IAEA or WNA web sites. (Author)

  10. Impacts of the Events on the 11. of September 2001 in the United States on Radiation Protection, the Nuclear Waste Management and the Nuclear Security in Germany

    International Nuclear Information System (INIS)

    Krumbach, H.; Steinmetz, H.J.; Odoj, R.

    2009-01-01

    This report describes the effects of the terrorist attacks of the 11 September 2001, when four airliners hijacked and crashed. These attacks take effects on radiation protection, nuclear disposal and nuclear safety in Germany. Some of the measures, which where taken after the September 11, 2001 in order to improve the safety of nuclear installations are presented in the following. The taken measures increasing security against terrorist attacks are also exemplarily described in this report. The examples include the introduction of new identity papers, which offer a higher security level as well as the prohibition of carrying liquids with more than 100 ml in the hand luggage. Also the human security measures taken by different companies since the attack happened are subject of the contribution. Due to the necessary confidentiality regarding the threat scenarios and the taken protective measures detailed descriptions of the measures in this report are limited. (authors)

  11. Geologic factors in the isolation of nuclear waste: evaluation of long-term geomorphic processes and events

    International Nuclear Information System (INIS)

    Mara, S.J.

    1979-01-01

    In this report the rate, duration, and magnitude of changes from geomorphic processes and events in the Southwest and the Gulf Coast over the next million years are projected. The projections were made by reviewing the pertinent literature; evaluating the geomorphic history of each region, especially that during the Quaternary Period; identifying the geomorphic processes and events likely to be significant in the two regions of interest; and estimating the average and worst-case conditions expected over the next million years

  12. Social impacts of hazardous and nuclear facilities and events: Implications for Nevada and the Yucca Mountain high-level nuclear waste repository; [Final report

    Energy Technology Data Exchange (ETDEWEB)

    Freudenburg, W.R. [Wisconsin Univ., Madison, WI (United States); Carter, L.F.; Willard, W. [Washington State Univ., Pullman, WA (United States); Lodwick, D.G. [Miami Univ., Oxford, OH (United States); Hardert, R.A. [Arizona State Univ., Tempe, AZ (United States); Levine, A.G. [State Univ. of New York, Buffalo, NY (United States). Dept. of Sociology; Kroll-Smith, S. [New Orleans Univ., LA (United States); Couch, S.R. [Pennsylvania State Univ., University Park, PA (United States); Edelstein, M.R. [Ramapo College, Mahwah, NJ (United States)

    1992-05-01

    Social impacts of a nuclear waste repository are described. Various case studies are cited such as Rocky Flats Plant, the Feed Materials Production Center, and Love Canal. The social impacts of toxic contamination, mitigating environmental stigma and loss of trust are also discussed.

  13. Social impacts of hazardous and nuclear facilities and events: Implications for Nevada and the Yucca Mountain high-level nuclear waste repository

    International Nuclear Information System (INIS)

    Freudenburg, W.R.; Carter, L.F.; Willard, W.; Lodwick, D.G.; Hardert, R.A.; Levine, A.G.; Couch, S.R.; Edelstein, M.R.

    1992-05-01

    Social impacts of a nuclear waste repository are described. Various case studies are cited such as Rocky Flats Plant, the Feed Materials Production Center, and Love Canal. The social impacts of toxic contamination, mitigating environmental stigma and loss of trust are also discussed

  14. [Contingency management in opioid substitution treatment].

    Science.gov (United States)

    Specka, M; Böning, A; Scherbaum, N

    2011-07-01

    The majority of opiate-dependent patients in substitution treatment show additional substance-related disorders. Concomitant use of heroin, alcohol, benzodiazepines or cocaine compromises treatment success. Concomitant drug use may be treated by using contingency management (CM) which is based on learning theory. In CM, abstinence from drugs, as verified by drug screenings, is reinforced directly and contingently. Reinforcers used in CM studies with substituted patients were, amongst others, vouchers and take-home privileges. Studies in the USA show a medium average effect of CM on drug consumption rates and abstinence. The effects decrease markedly after the end of the intervention. We discuss whether CM is applicable within the German substitution treatment system and how it can be combined with other interventions such as selective detoxification treatments or cognitive-behavioural programmes. © Georg Thieme Verlag KG Stuttgart · New York.

  15. Abnormal condition and events analysis for instrumentation and control systems. Volume 1: Methodology for nuclear power plant digital upgrades. Final report

    International Nuclear Information System (INIS)

    McKemy, S.; Marcelli, M.; Boehmer, N.; Crandall, D.

    1996-01-01

    The ACES project was initiated to identify a cost-effective methodology for addressing abnormal conditions and events (ACES) in digital upgrades to nuclear power plant systems, as introduced by IEEE Standard 7-4.3.2-1993. Several methodologies and techniques currently in use in the defense, aerospace, and other communities for the assurance of digital safety systems were surveyed, and although several were shown to possess desirable qualities, non sufficiently met the needs of the nuclear power industry. This report describes a tailorable methodology for performing ACES analysis that is based on the more desirable aspects of the reviewed methodologies and techniques. The methodology is applicable to both safety- and non-safety-grade systems, addresses hardware, software, and system-level concerns, and can be applied in either a lifecycle or post-design timeframe. Employing this methodology for safety systems should facilitate the digital upgrade licensing process

  16. Volcanic Eruption: Students Develop a Contingency Plan

    Science.gov (United States)

    Meisinger, Philipp; Wittlich, Christian

    2013-04-01

    Dangerous, loud, sensational, exciting - natural hazards have what it takes to get students attention around the globe. Arising interest is the first step to develop an intrinsic motivation to learn about the matter and endure the hardships that students might discover along the way of the unit. Natural hazards thereby establish a close-knit connection between physical and anthropological geography through analyzing the hazardous event and its consequences for the people living in the affected area. Following a general principle of didactics we start searching right on our doorsteps to offer students the possibility to gain knowledge on the familiar and later transfer it to the unknown example. Even in Southwest Germany - a region that is rather known for its wine than its volcanic activity - we can find a potentially hazardous region. The "Laacher See" volcano (a caldera lake) in northern Rhineland-Palatinate is according to Prof. H.U. Schminke a "potentially active volcano" . Its activity can be proven by seismic activities, or experienced when visiting the lake's southeastern shore, where carbondioxid and sulphur gases from the underlying magma chamber still bubble up. The Laacher See is part of a range of volcanoes (classified from 'potentially active' to 'no longer active') of the East Eifel Volcanic Field. Precariously the Laacher See is located closely to the densely populated agglomerations of Cologne (NE, distance: 45 km) and the former capital Bonn (NE: 35km), as well as Koblenz (E: 24km) and the Rhine river. Apart from that, the towns of Andernach (E: 8km ± 30 000 inhabitants) and Mayen (SW: 11km ±20 000 inhabitants) and many smaller towns and villages are nearby due to economic reasons. The number of people affected by a possible eruption easily exceeds two million people considering the range as prime measurement. The underlying danger, as projected in a simulation presented by Prof. Schminke, is a lava stream running down the Brohltal valley

  17. Nuclear

    International Nuclear Information System (INIS)

    2014-01-01

    This document proposes a presentation and discussion of the main notions, issues, principles, or characteristics related to nuclear energy: radioactivity (presence in the environment, explanation, measurement, periods and activities, low doses, applications), fuel cycle (front end, mining and ore concentration, refining and conversion, fuel fabrication, in the reactor, back end with reprocessing and recycling, transport), the future of the thorium-based fuel cycle (motivations, benefits and drawbacks), nuclear reactors (principles of fission reactors, reactor types, PWR reactors, BWR, heavy-water reactor, high temperature reactor of HTR, future reactors), nuclear wastes (classification, packaging and storage, legal aspects, vitrification, choice of a deep storage option, quantities and costs, foreign practices), radioactive releases of nuclear installations (main released radio-elements, radioactive releases by nuclear reactors and by La Hague plant, gaseous and liquid effluents, impact of releases, regulation), the OSPAR Convention, management and safety of nuclear activities (from control to quality insurance, to quality management and to sustainable development), national safety bodies (mission, means, organisation and activities of ASN, IRSN, HCTISN), international bodies, nuclear and medicine (applications of radioactivity, medical imagery, radiotherapy, doses in nuclear medicine, implementation, the accident in Epinal), nuclear and R and D (past R and D programmes and expenses, main actors in France and present funding, main R and D axis, international cooperation)

  18. Messiahs, pachacutis and prophets. The apocalypse or contingency discourse in Peru

    Directory of Open Access Journals (Sweden)

    Lucero de Vivanco

    2012-11-01

    Full Text Available Facing the pervasive presence of an apocalyptic imaginariness in Peruvian narrative fiction, this article shows that the Apocalypse has also been evoked by “serious” or non-fictional discourses, primarily in order to interpret issues related to social and political contingency. From this position, the article reviews a series of political events along Herbert Morote’s Réquiem por Perú, mi patria, a literary essay that interprets national reality.

  19. Food Marketing Technology and Contingency Market Valuation

    OpenAIRE

    Garth J. Holloway; Anthony C. Zwart

    1993-01-01

    Marketing activities are introduced into a rational expectations model of the food marketing system. The model is used to evaluate effects of alternative marketing technologies on the distribution of the benefits of contingency markets in agriculture. Benefits depend on two parameters: the cost share of farm inputs and the elasticity of substitution between farm and nonfarm inputs in food marketing. Over a broad spectrum of technologies, consumers are likely to be the net beneficiaries and fa...

  20. Capacity Adjustment through Contingent Staffing Outsourcing

    OpenAIRE

    Neubert , Gilles; Adjadj , Philippe

    2009-01-01

    International audience; For a long time, contingent staffing was considered as the responsability of the Human Resource department. The high needs of workforce flexibility combined with disseminated agencies have led some companies to a great number of labor suppliers. This situation has produced important cost variation, poor quality of service, and important risk due to the mistunderstanding by local managers of legal considerations. To face this situation, companies have started to move fr...