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Sample records for external events analysis

  1. Probabilistic analysis of external events with focus on the Fukushima event

    International Nuclear Information System (INIS)

    Kollasko, Heiko; Jockenhoevel-Barttfeld, Mariana; Klapp, Ulrich

    2014-01-01

    External hazards are those natural or man-made hazards to a site and facilities that are originated externally to both the site and its processes, i.e. the duty holder may have very little or no control over the hazard. External hazards can have the potential of causing initiating events at the plant, typically transients like e.g., loss of offsite power. Simultaneously, external events may affect safety systems required to control the initiating event and, where applicable, also back-up systems implemented for risk-reduction. The plant safety may especially be threatened when loads from external hazards exceed the load assumptions considered in the design of safety-related systems, structures and components. Another potential threat is given by hazards inducing initiating events not considered in the safety demonstration otherwise. An example is loss of offsite power combined with prolonged plant isolation. Offsite support, e.g., delivery of diesel fuel oil, usually credited in the deterministic safety analysis may not be possible in this case. As the Fukushima events have shown, the biggest threat is likely given by hazards inducing both effects. Such hazards may well be dominant risk contributors even if their return period is very high. In order to identify relevant external hazards for a certain Nuclear Power Plant (NPP) location, a site specific screening analysis is performed, both for single events and for combinations of external events. As a result of the screening analysis, risk significant and therefore relevant (screened-in) single external events and combinations of them are identified for a site. The screened-in events are further considered in a detailed event tree analysis in the frame of the Probabilistic Safety Analysis (PSA) to calculate the core damage/large release frequency resulting from each relevant external event or from each relevant combination. Screening analyses of external events performed at AREVA are based on the approach provided

  2. External event analysis methods for NUREG-1150

    International Nuclear Information System (INIS)

    Bohn, M.P.; Lambright, J.A.

    1989-01-01

    The US Nuclear Regulatory Commission is sponsoring probabilistic risk assessments of six operating commercial nuclear power plants as part of a major update of the understanding of risk as provided by the original WASH-1400 risk assessments. In contrast to the WASH-1400 studies, at least two of the NUREG-1150 risk assessments will include an analysis of risks due to earthquakes, fires, floods, etc., which are collectively known as eternal events. This paper summarizes the methods to be used in the external event analysis for NUREG-1150 and the results obtained to date. The two plants for which external events are being considered are Surry and Peach Bottom, a PWR and BWR respectively. The external event analyses (through core damage frequency calculations) were completed in June 1989, with final documentation available in September. In contrast to most past external event analyses, wherein rudimentary systems models were developed reflecting each external event under consideration, the simplified NUREG-1150 analyses are based on the availability of the full internal event PRA systems models (event trees and fault trees) and make use of extensive computer-aided screening to reduce them to sequence cut sets important to each external event. This provides two major advantages in that consistency and scrutability with respect to the internal event analysis is achieved, and the full gamut of random and test/maintenance unavailabilities are automatically included, while only those probabilistically important survive the screening process. Thus, full benefit of the internal event analysis is obtained by performing the internal and external event analyses sequentially

  3. MGR External Events Hazards Analysis

    International Nuclear Information System (INIS)

    Booth, L.

    1999-01-01

    The purpose and objective of this analysis is to apply an external events Hazards Analysis (HA) to the License Application Design Selection Enhanced Design Alternative 11 [(LADS EDA II design (Reference 8.32))]. The output of the HA is called a Hazards List (HL). This analysis supersedes the external hazards portion of Rev. 00 of the PHA (Reference 8.1). The PHA for internal events will also be updated to the LADS EDA II design but under a separate analysis. Like the PHA methodology, the HA methodology provides a systematic method to identify potential hazards during the 100-year Monitored Geologic Repository (MGR) operating period updated to reflect the EDA II design. The resulting events on the HL are candidates that may have potential radiological consequences as determined during Design Basis Events (DBEs) analyses. Therefore, the HL that results from this analysis will undergo further screening and analysis based on the criteria that apply during the performance of DBE analyses

  4. 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)

  5. 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)

  6. Risk and sensitivity analysis in relation to external events

    International Nuclear Information System (INIS)

    Alzbutas, R.; Urbonas, R.; Augutis, J.

    2001-01-01

    This paper presents risk and sensitivity analysis of external events impacts on the safe operation in general and in particular the Ignalina Nuclear Power Plant safety systems. Analysis is based on the deterministic and probabilistic assumptions and assessment of the external hazards. The real statistic data are used as well as initial external event simulation. The preliminary screening criteria are applied. The analysis of external event impact on the NPP safe operation, assessment of the event occurrence, sensitivity analysis, and recommendations for safety improvements are performed for investigated external hazards. Such events as aircraft crash, extreme rains and winds, forest fire and flying parts of the turbine are analysed. The models are developed and probabilities are calculated. As an example for sensitivity analysis the model of aircraft impact is presented. The sensitivity analysis takes into account the uncertainty features raised by external event and its model. Even in case when the external events analysis show rather limited danger, the sensitivity analysis can determine the highest influence causes. These possible variations in future can be significant for safety level and risk based decisions. Calculations show that external events cannot significantly influence the safety level of the Ignalina NPP operation, however the events occurrence and propagation can be sufficiently uncertain.(author)

  7. External events analysis for experimental fusion facilities

    International Nuclear Information System (INIS)

    Cadwallader, L.C.

    1990-01-01

    External events are those off-normal events that threaten facilities either from outside or inside the building. These events, such as floods, fires, and earthquakes, are among the leading risk contributors for fission power plants, and the nature of fusion facilities indicates that they may also lead fusion risk. This paper gives overviews of analysis methods, references good analysis guidance documents, and gives design tips for mitigating the effects of floods and fires, seismic events, and aircraft impacts. Implications for future fusion facility siting are also discussed. Sites similar to fission plant sites are recommended. 46 refs

  8. External events analysis in PSA studies for Czech NPPs

    International Nuclear Information System (INIS)

    Holy, J.; Hustak, S.; Kolar, L.; Jaros, M.; Hladky, M.; Mlady, O.

    2014-01-01

    The purpose of the paper is to summarize current status of natural external hazards analysis in the PSA projects maintained in Czech Republic for both Czech NPPs - Dukovany and Temelin. The focus of the presentation is put upon the basic milestones in external event analysis effort - identification of external hazards important for Czech NPPs sites, screening out of the irrelevant hazards, modeling of plant response to the initiating events, including the basic activities regarding vulnerability and fragility analysis (supported with on-site analysis), quantification of accident sequences, interpretation of results and development of measures decreasing external events risk. The following external hazards are discussed in the paper, which have been addressed during several last years in PSA projects for Czech NPPs: 1)seismicity, 2)extremely low temperature 3)extremely high temperature 4)extreme wind 5)extreme precipitation (water, snow) 6)transport of dangerous substances (as an example of man-made hazard with some differences identified in comparison with natural hazards) 7)other hazards, which are not considered as very important for Czech NPPs, were screened out in the initial phase of the analysis, but are known as potential problem areas abroad. The paper is a result of coordinated effort with participation of experts and staff from engineering support organization UJV Rez, a.s. and NPPs located in Czech Republic - Dukovany and Temelin. (authors)

  9. External events analysis for the Savannah River Site K reactor

    International Nuclear Information System (INIS)

    Brandyberry, M.D.; Wingo, H.E.

    1990-01-01

    The probabilistic external events analysis performed for the Savannah River Site K-reactor PRA considered many different events which are generally perceived to be ''external'' to the reactor and its systems, such as fires, floods, seismic events, and transportation accidents (as well as many others). Events which have been shown to be significant contributors to risk include seismic events, tornados, a crane failure scenario, fires and dam failures. The total contribution to the core melt frequency from external initiators has been found to be 2.2 x 10 -4 per year, from which seismic events are the major contributor (1.2 x 10 -4 per year). Fire initiated events contribute 1.4 x 10 -7 per year, tornados 5.8 x 10 -7 per year, dam failures 1.5 x 10 -6 per year and the crane failure scenario less than 10 -4 per year to the core melt frequency. 8 refs., 3 figs., 5 tabs

  10. Technical basis document for external events

    International Nuclear Information System (INIS)

    OBERG, B.D.

    2003-01-01

    This document supports the Tank Farms Documented Safety Analysis and presents the technical basis for the FR-equencies of externally initiated accidents. The consequences of externally initiated events are discussed in other documents that correspond to the accident that was caused by the external event. The external events include aircraft crash, vehicle accident, range fire, and rail accident

  11. 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)

  12. External Events PSA for the Paks NPP

    International Nuclear Information System (INIS)

    Bareith, Attila; Karsa, Zoltan; Siklossy, Tamas; Vida, Zoltan

    2014-01-01

    Initially, probabilistic safety assessment of external events was limited to the analysis of earthquakes for the Paks Nuclear Power Plant in Hungary. The level 1 seismic PSA was completed in 2002 showing a significant contribution of seismic failures to core damage risk. Although other external events of natural origin had previously been screened out from detailed plant PSA mostly on the basis of event frequencies, a review of recent experience on extreme weather phenomena made during the periodic safety review of the plant led to the initiation of PSA for external events other than earthquakes in 2009. In the meantime, the accident of the Fukushima Dai-ichi Nuclear Power Plant confirmed further the importance of such an analysis. The external event PSA for the Paks plant followed the commonly known steps: selection and screening of external hazards, hazard assessment for screened-in external events, analysis of plant response and fragility, PSA model development, and risk quantification and interpretation of results. As a result of event selection and screening the following weather related external hazards were subject to detailed analysis: extreme wind, extreme rainfall (precipitation), extreme snow, extremely high and extremely low temperatures, lightning, frost and ice formation. The analysis proved to be a significant challenge due to scarcity of data, lack of knowledge, as well as limitations of existing PSA methodologies. This paper presents an overview of the external events PSA performed for the Paks NPP. Important methodological aspects are summarised. Key analysis findings and unresolved issues that need further elaboration are highlighted. Development of external events PSA for the Paks NPP was completed by the end of 2012. The analysis followed the commonly known steps: selection and screening of external hazards, hazard assessment for screened-in external events, analysis of plant response and fragility, PSA model development, and risk

  13. Vulnerability analysis of a PWR to an external event

    International Nuclear Information System (INIS)

    Aruety, S.; Ilberg, D.; Hertz, Y.

    1980-01-01

    The Vulnerability of a Nuclear Power Plant (NPP) to external events is affected by several factors such as: the degree of redundancy of the reactor systems, subsystems and components; the separation of systems provided in the general layout; the extent of the vulnerable area, i.e., the area which upon being affected by an external event will result in system failure; and the time required to repair or replace the systems, when allowed. The present study offers a methodology, using Probabilistic Safety Analysis, to evaluate the relative importance of the above parameters in reducing the vulnerability of reactor safety systems. Several safety systems of typical PWR's are analyzed as examples. It was found that the degree of redundancy and physical separation of the systems has the most prominent effect on the vulnerability of the NPP

  14. Analysis of core damage frequency due to external events at the DOE [Department of Energy] N-Reactor

    International Nuclear Information System (INIS)

    Lambright, J.A.; Bohn, M.P.; Daniel, S.L.; Baxter, J.T.; Johnson, J.J.; Ravindra, M.K.; Hashimoto, P.O.; Mraz, M.J.; Tong, W.H.; Conoscente, J.P.; Brosseau, D.A.

    1990-11-01

    A complete external events probabilistic risk assessment has been performed for the N-Reactor power plant, making full use of all insights gained during the past ten years' developments in risk assessment methodologies. A detailed screening analysis was performed which showed that all external events had negligible contribution to core damage frequency except fires, seismic events, and external flooding. A limited scope analysis of the external flooding risk indicated that it is not a major risk contributor. Detailed analyses of the fire and seismic risks resulted in total (mean) core damage frequencies of 1.96E-5 and 4.60E-05 per reactor year, respectively. Detailed uncertainty analyses were performed for both fire and seismic risks. These results show that the core damage frequency profile for these events is comparable to that found for existing commercial power plants if proposed fixes are completed as part of the restart program. 108 refs., 85 figs., 80 tabs

  15. Analysis of core damage frequency due to external events at the DOE (Department of Energy) N-Reactor

    Energy Technology Data Exchange (ETDEWEB)

    Lambright, J.A.; Bohn, M.P.; Daniel, S.L. (Sandia National Labs., Albuquerque, NM (USA)); Baxter, J.T. (Westinghouse Hanford Co., Richland, WA (USA)); Johnson, J.J.; Ravindra, M.K.; Hashimoto, P.O.; Mraz, M.J.; Tong, W.H.; Conoscente, J.P. (EQE, Inc., San Francisco, CA (USA)); Brosseau, D.A. (ERCE, Inc., Albuquerque, NM (USA))

    1990-11-01

    A complete external events probabilistic risk assessment has been performed for the N-Reactor power plant, making full use of all insights gained during the past ten years' developments in risk assessment methodologies. A detailed screening analysis was performed which showed that all external events had negligible contribution to core damage frequency except fires, seismic events, and external flooding. A limited scope analysis of the external flooding risk indicated that it is not a major risk contributor. Detailed analyses of the fire and seismic risks resulted in total (mean) core damage frequencies of 1.96E-5 and 4.60E-05 per reactor year, respectively. Detailed uncertainty analyses were performed for both fire and seismic risks. These results show that the core damage frequency profile for these events is comparable to that found for existing commercial power plants if proposed fixes are completed as part of the restart program. 108 refs., 85 figs., 80 tabs.

  16. N reactor external events probabilistic risk assessment

    International Nuclear Information System (INIS)

    Baxter, J.T.

    1989-01-01

    An external events probabilistic risk assessment of the N Reactor has been completed. The methods used are those currently being proposed for external events analysis in NUREG-1150. Results are presented for the external hazards that survived preliminary screening. They are earthquake, fire, and external flood. Core damage frequencies for these hazards are shown to be comparable to those for commercial pressurized water reactors. Dominant fire sequences are described and related to 10 CFR 50, Appendix R design requirements. Potential remedial measures that reduce fire core damage risk are described including modifications to fire protection systems, procedure changes, and addition of new administrative controls. Dominant seismic sequences are described. The effect of non-safety support system dependencies on seismic risk is presented

  17. Methods for external event screening quantification: Risk Methods Integration and Evaluation Program (RMIEP) methods development

    International Nuclear Information System (INIS)

    Ravindra, M.K.; Banon, H.

    1992-07-01

    In this report, the scoping quantification procedures for external events in probabilistic risk assessments of nuclear power plants are described. External event analysis in a PRA has three important goals; (1) the analysis should be complete in that all events are considered; (2) by following some selected screening criteria, the more significant events are identified for detailed analysis; (3) the selected events are analyzed in depth by taking into account the unique features of the events: hazard, fragility of structures and equipment, external-event initiated accident sequences, etc. Based on the above goals, external event analysis may be considered as a three-stage process: Stage I: Identification and Initial Screening of External Events; Stage II: Bounding Analysis; Stage III: Detailed Risk Analysis. In the present report, first, a review of published PRAs is given to focus on the significance and treatment of external events in full-scope PRAs. Except for seismic, flooding, fire, and extreme wind events, the contributions of other external events to plant risk have been found to be negligible. Second, scoping methods for external events not covered in detail in the NRC's PRA Procedures Guide are provided. For this purpose, bounding analyses for transportation accidents, extreme winds and tornadoes, aircraft impacts, turbine missiles, and chemical release are described

  18. Identification and analysis of external event combinations for Hanhikivi 1PRA

    Energy Technology Data Exchange (ETDEWEB)

    Helander, Juho [Fennovoima Oy, Helsinki (Finland)

    2017-03-15

    Fennovoima's nuclear power plant, Hanhikivi 1, Pyhäjoki, Finland, is currently in design phase, and its construction is scheduled to begin in 2018 and electricity production in 2024. The objective of this paper is to produce a preliminary list of safety-significant external event combinations including preliminary probability estimates, to be used in the probabilistic risk assessment of Hanhikivi 1 plant. Starting from the list of relevant single events, the relevant event combinations are identified based on seasonal variation, preconditions related to different events, and dependencies (fundamental and cascade type) between events. Using this method yields 30 relevant event combinations of two events for the Hanhikivi site. The preliminary probability of each combination is evaluated, and event combinations with extremely low probability are excluded from further analysis. Event combinations of three or more events are identified by adding possible events to the remaining combinations of two events. Finally, 10 relevant combinations of two events and three relevant combinations of three events remain. The results shall be considered preliminary and will be updated after evaluating more detailed effects of different events on plant safety.

  19. 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)

  20. Hazard analysis of typhoon-related external events using extreme value theory

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Yo Chan; Jang, Seung Cheol [Integrated Safety Assessment Division, Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of); Lim, Tae Jin [Dept. of Industrial Information Systems Engineering, Soongsil University, Seoul (Korea, Republic of)

    2015-02-15

    After the Fukushima accident, the importance of hazard analysis for extreme external events was raised. To analyze typhoon-induced hazards, which are one of the significant disasters of East Asian countries, a statistical analysis using the extreme value theory, which is a method for estimating the annual exceedance frequency of a rare event, was conducted for an estimation of the occurrence intervals or hazard levels. For the four meteorological variables, maximum wind speed, instantaneous wind speed, hourly precipitation, and daily precipitation, the parameters of the predictive extreme value theory models were estimated. The 100-year return levels for each variable were predicted using the developed models and compared with previously reported values. It was also found that there exist significant long-term climate changes of wind speed and precipitation. A fragility analysis should be conducted to ensure the safety levels of a nuclear power plant for high levels of wind speed and precipitation, which exceed the results of a previous analysis.

  1. External flooding event analysis in a PWR-W with MAAP5

    International Nuclear Information System (INIS)

    Fernandez-Cosials, Mikel Kevin; Jimenez, Gonzalo; Barreira, Pilar; Queral, Cesar

    2015-01-01

    Highlights: • External flooding preceded by a SCRAM is simulated with MAAP5.01. • Sensitivities include AFW-TDP, SLOCA and operator preventive actions. • SLOCA flow is the dominant factor in the sequences. • Vessel failure is avoidable with operator preventive actions. - Abstract: The Fukushima accident has drawn attention even more to the importance of external events and loss of energy supply on safety analysis. Since 2011, several Station Blackout (SBO) analyses have been done for all type of reactors. The most post-Fukushima studies analyze a pure and straight SBO transient, but the Fukushima accident was more complex than a standard SBO. At Fukushima accident, the SBO was a consequence of an external flooding from the tsunami and occurred 40 min after an emergency shutdown (SCRAM) caused by the earthquake. The first objective of this paper is to assume the consequences of an external flooding accident in a PWR site caused by a river flood, a dam break or a tsunami, where all the plant is damaged, not only the diesel generators. The second objective is to analyze possible actions to be performed in the time between the earthquake event (that causes a SCRAM) and the external flooding arrival, which could be applicable to accidents such as dam failures or river flooding in order to avoid more severe consequences, delay the core damage and improve the accident management. The results reveal how the actuation of the different systems and equipments affect the core damage time and how some actions could delay the core damage time enough to increase the possibility of AC power recovery

  2. Review IPEEE C.N. external event Vandellos II

    International Nuclear Information System (INIS)

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

    2010-01-01

    Within the process of maintaining and updating the risk analysis of CN Vandellos II, results from the review of the study of vulnerability of the plant against severe accidents caused by external events (Individual Plant Examination on Extornal Events, IPEEE).

  3. 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.

  4. Impact of external events on site evaluation: a probabilistic approach

    International Nuclear Information System (INIS)

    Jaccarino, E.; Giuliani, P.; Zaffiro, C.

    1975-01-01

    A probabilistic method is proposed for definition of the reference external events of nuclear sites. The external events taken into account are earthquakes, floods and tornadoes. On the basis of the available historical data for each event it is possible to perform statistical analyses to determine the probability of occurrence on site of events of given characteristics. For earthquakes, the method of analysis takes into consideration both the annual frequency of seismic events in Italy and the probabilistic distribution of areas stricken by each event. For floods, the methods of analysis of hydrological data and the basic criteria for the determination of design events are discussed and the general lines of the hydraulic analysis of a nuclear site are shown. For tornadoes, the statistical analysis has been performed for the events which occurred in Italy during the last 40 years; these events have been classified according to an empirical intensity scale. The probability of each reference event should be a function of the potential radiological damage associated with the particular type of plant which must be installed on the site. Thus the reference event could be chosen such that for the whole of the national territory the risk for safety and environmental protection is the same. (author)

  5. 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

  6. IPEEE Review of other external events of the NPP Asco

    International Nuclear Information System (INIS)

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

    2011-01-01

    Within the process of maintaining and updating the risk analysis of the NPP Asco, results from the review of the vulnerability study of the plant against severe accidents caused by external success (Individual Plant Examination of External Events, IPEEE).

  7. Application of declarative modeling approaches for external events

    International Nuclear Information System (INIS)

    Anoba, R.C.

    2005-01-01

    Probabilistic Safety Assessments (PSAs) are increasingly being used as a tool for supporting the acceptability of design, procurement, construction, operation, and maintenance activities at Nuclear Power Plants. Since the issuance of Generic Letter 88-20 and subsequent IPE/IPEEE assessments, the NRC has issued several Regulatory Guides such as RG 1.174 to describe the use of PSA in risk-informed regulation activities. Most PSA have the capability to address internal events including internal floods. As the more demands are being placed for using the PSA to support risk-informed applications, there has been a growing need to integrate other eternal events (Seismic, Fire, etc.) into the logic models. Most external events involve spatial dependencies and usually impact the logic models at the component level. Therefore, manual insertion of external events impacts into a complex integrated fault tree model may be too cumbersome for routine uses of the PSA. Within the past year, a declarative modeling approach has been developed to automate the injection of external events into the PSA. The intent of this paper is to introduce the concept of declarative modeling in the context of external event applications. A declarative modeling approach involves the definition of rules for injection of external event impacts into the fault tree logic. A software tool such as the EPRI's XInit program can be used to interpret the pre-defined rules and automatically inject external event elements into the PSA. The injection process can easily be repeated, as required, to address plant changes, sensitivity issues, changes in boundary conditions, etc. External event elements may include fire initiating events, seismic initiating events, seismic fragilities, fire-induced hot short events, special human failure events, etc. This approach has been applied at a number of US nuclear power plants including a nuclear power plant in Romania. (authors)

  8. Treatment of external events in the linked event tree methodology NPP Goesgen - Daeniken example

    International Nuclear Information System (INIS)

    Kozlik, Thomas

    2014-01-01

    The NPP Goesgen-Daeniken uses a combined level 1 / level 2 PSA model for its event analyses. The model uses a linked event tree approach, using the software RISKMAN R . Each initiating event passes through a modularized event tree structure, consisting of external events pre-trees, alignment and support systems trees and front-line and containment response trees. This paper explains the structure of the linked event trees. Switches are used to bypass certain trees for specific initiating events. The screening process applied to possible external events is explained. The final scope of considered natural external events in the Goesgen PSA consists of earthquakes, seasonal events causing cooling water intake plugging or external floods. The structure of the natural external events pre-trees is explained. The treatment of external floods is explained in more detail. Floods at the Goesgen site are caused by extreme river flows into the old branch of the Aare river. A new model has been developed to analyse the probabilistic flood hazard using a bivariate distribution (water level and flood duration). Analysing the statistical data, the time trend had to be considered. The Goesgen PSA models 7 external flood initiating events, considering different water levels and durations at the flooded plant site. The building fragilities were developed in terms of resistance times. The RISKMAN R external flood pre-tree consists of top events for operator actions and failure of the building functions, which leads to the functional failure of equipment located at the lower elevation of the building. (author)

  9. Advanced Reactor Passive System Reliability Demonstration Analysis for an External Event

    Directory of Open Access Journals (Sweden)

    Matthew Bucknor

    2017-03-01

    Full Text Available Many advanced reactor designs rely on passive systems to fulfill safety functions during accident sequences. These systems depend heavily on boundary conditions to induce a motive force, meaning the system can fail to operate as intended because of deviations in boundary conditions, rather than as the result of physical failures. Furthermore, passive systems may operate in intermediate or degraded modes. These factors make passive system operation difficult to characterize within a traditional probabilistic framework that only recognizes discrete operating modes and does not allow for the explicit consideration of time-dependent boundary conditions. Argonne National Laboratory has been examining various methodologies for assessing passive system reliability within a probabilistic risk assessment for a station blackout event at an advanced small modular reactor. This paper provides an overview of a passive system reliability demonstration analysis for an external event. Considering an earthquake with the possibility of site flooding, the analysis focuses on the behavior of the passive Reactor Cavity Cooling System following potential physical damage and system flooding. The assessment approach seeks to combine mechanistic and simulation-based methods to leverage the benefits of the simulation-based approach without the need to substantially deviate from conventional probabilistic risk assessment techniques. Although this study is presented as only an example analysis, the results appear to demonstrate a high level of reliability of the Reactor Cavity Cooling System (and the reactor system in general for the postulated transient event.

  10. Advanced reactor passive system reliability demonstration analysis for an external event

    Energy Technology Data Exchange (ETDEWEB)

    Bucknor, Matthew; Grabaskas, David; Brunett, Acacia J.; Grelle, Austin [Argonne National Laboratory, Argonne (United States)

    2017-03-15

    Many advanced reactor designs rely on passive systems to fulfill safety functions during accident sequences. These systems depend heavily on boundary conditions to induce a motive force, meaning the system can fail to operate as intended because of deviations in boundary conditions, rather than as the result of physical failures. Furthermore, passive systems may operate in intermediate or degraded modes. These factors make passive system operation difficult to characterize within a traditional probabilistic framework that only recognizes discrete operating modes and does not allow for the explicit consideration of time-dependent boundary conditions. Argonne National Laboratory has been examining various methodologies for assessing passive system reliability within a probabilistic risk assessment for a station blackout event at an advanced small modular reactor. This paper provides an overview of a passive system reliability demonstration analysis for an external event. Considering an earthquake with the possibility of site flooding, the analysis focuses on the behavior of the passive Reactor Cavity Cooling System following potential physical damage and system flooding. The assessment approach seeks to combine mechanistic and simulation-based methods to leverage the benefits of the simulation-based approach without the need to substantially deviate from conventional probabilistic risk assessment techniques. Although this study is presented as only an example analysis, the results appear to demonstrate a high level of reliability of the Reactor Cavity Cooling System (and the reactor system in general) for the postulated transient event.

  11. Advanced reactor passive system reliability demonstration analysis for an external event

    International Nuclear Information System (INIS)

    Bucknor, Matthew; Grabaskas, David; Brunett, Acacia J.; Grelle, Austin

    2017-01-01

    Many advanced reactor designs rely on passive systems to fulfill safety functions during accident sequences. These systems depend heavily on boundary conditions to induce a motive force, meaning the system can fail to operate as intended because of deviations in boundary conditions, rather than as the result of physical failures. Furthermore, passive systems may operate in intermediate or degraded modes. These factors make passive system operation difficult to characterize within a traditional probabilistic framework that only recognizes discrete operating modes and does not allow for the explicit consideration of time-dependent boundary conditions. Argonne National Laboratory has been examining various methodologies for assessing passive system reliability within a probabilistic risk assessment for a station blackout event at an advanced small modular reactor. This paper provides an overview of a passive system reliability demonstration analysis for an external event. Considering an earthquake with the possibility of site flooding, the analysis focuses on the behavior of the passive Reactor Cavity Cooling System following potential physical damage and system flooding. The assessment approach seeks to combine mechanistic and simulation-based methods to leverage the benefits of the simulation-based approach without the need to substantially deviate from conventional probabilistic risk assessment techniques. Although this study is presented as only an example analysis, the results appear to demonstrate a high level of reliability of the Reactor Cavity Cooling System (and the reactor system in general) for the postulated transient event

  12. Significant aspects of the external event analysis methodology of the Jose Cabrera NPP PSA

    International Nuclear Information System (INIS)

    Barquin Duena, A.; Martin Martinez, A.R.; Boneham, P.S.; Ortega Prieto, P.

    1994-01-01

    This paper describes the following advances in the methodology for Analysis of External Events in the PSA of the Jose Cabrera NPP: In the Fire Analysis, a version of the COMPBRN3 CODE, modified by Empresarios Agrupados according to the guidelines of Appendix D of the NUREG/CR-5088, has been used. Generic cases were modelled and general conclusions obtained, applicable to fire propagation in closed areas. The damage times obtained were appreciably lower than those obtained with the previous version of the code. The Flood Analysis methodology is based on the construction of event trees to represent flood propagation dependent on the condition of the communication paths between areas, and trees showing propagation stages as a function of affected areas and damaged mitigation equipment. To determine temporary evolution of the flood area level, the CAINZO-EA code has been developed, adapted to specific plant characteristics. In both the Fire and Flood Analyses a quantification methodology has been adopted, which consists of analysing the damages caused at each stage of growth or propagation and identifying, in the Internal Events models, the gates, basic events or headers to which safe failure (probability 1) due to damages is assigned. (Author)

  13. Implementation of PSA models to estimate the probabilities associated with external event combination

    International Nuclear Information System (INIS)

    Burgazzi, Luciano

    2014-01-01

    This note endeavors to address some significant issues revealed by the Fukushima accident in Japan in 2011, such as the analysis of various dependency aspects arisen in the light of the external event PSA framework, as the treatment of the correlated hazards. To this aim some foundational notions to implement the PSA models related to specific aspects, like the external hazard combination, e.g., earthquake and tsunami as at the Fukushima accident, and the external hazard-caused internal events, e.g., seismic induced fire, are proposed and discussed to be incorporated within the risk assessment structure. Risk assessment of external hazards is required and utilized as an integrated part of PRA for operating and new reactor units. In the light of the Fukushima accident, of special interest are correlated events, whose modelling is proposed in the present study, in the form of some theoretical concepts, which lay the foundations for the PSA framework implementation. An applicative example is presented for illustrative purposes, since the analysis is carried out on the basis of generic numerical values assigned to an oversimplified model and results are achieved without any baseline comparison. Obviously the first step aimed at the process endorsement is the analysis of all available information in order to determine the level of applicability of the observed specific plant site events to the envisaged model and the statistical correlation analysis for event occurrence data that can be used as part of this process. Despite these drawbacks that actually do not qualify the achieved results, the present work represents an exploratory study aimed at resolving current open issues to be resolved in the PSA, like topics related to unanticipated scenarios: the combined external hazards of the earthquake and tsunami in Fukushima, external hazards causing internal events, such as seismic induced fire. These topics are to be resolved among the other ones as emerging from the

  14. 3D Simulation of External Flooding Events for the RISMC Pathway

    International Nuclear Information System (INIS)

    Prescott, Steven; Mandelli, Diego; Sampath, Ramprasad; Smith, Curtis; Lin, Linyu

    2015-01-01

    Incorporating 3D simulations as part of the Risk-Informed Safety Margins Characterization (RISMIC) Toolkit allows analysts to obtain a more complete picture of complex system behavior for events including external plant hazards. External events such as flooding have become more important recently – however these can be analyzed with existing and validated simulated physics toolkits. In this report, we describe these approaches specific to flooding-based analysis using an approach called Smoothed Particle Hydrodynamics. The theory, validation, and example applications of the 3D flooding simulation are described. Integrating these 3D simulation methods into computational risk analysis provides a spatial/visual aspect to the design, improves the realism of results, and can prove visual understanding to validate the analysis of flooding.

  15. 3D Simulation of External Flooding Events for the RISMC Pathway

    Energy Technology Data Exchange (ETDEWEB)

    Prescott, Steven [Idaho National Lab. (INL), Idaho Falls, ID (United States); Mandelli, Diego [Idaho National Lab. (INL), Idaho Falls, ID (United States); Sampath, Ramprasad [Idaho National Lab. (INL), Idaho Falls, ID (United States); Smith, Curtis [Idaho National Lab. (INL), Idaho Falls, ID (United States); Lin, Linyu [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2015-09-01

    Incorporating 3D simulations as part of the Risk-Informed Safety Margins Characterization (RISMIC) Toolkit allows analysts to obtain a more complete picture of complex system behavior for events including external plant hazards. External events such as flooding have become more important recently – however these can be analyzed with existing and validated simulated physics toolkits. In this report, we describe these approaches specific to flooding-based analysis using an approach called Smoothed Particle Hydrodynamics. The theory, validation, and example applications of the 3D flooding simulation are described. Integrating these 3D simulation methods into computational risk analysis provides a spatial/visual aspect to the design, improves the realism of results, and can prove visual understanding to validate the analysis of flooding.

  16. Procedures for the external event core damage frequency analyses for NUREG-1150

    International Nuclear Information System (INIS)

    Bohn, M.P.; Lambright, J.A.

    1990-11-01

    This report presents methods which can be used to perform the assessment of risk due to external events at nuclear power plants. These methods were used to perform the external events risk assessments for the Surry and Peach Bottom nuclear power plants as part of the NRC-sponsored NUREG-1150 risk assessments. These methods apply to the full range of hazards such as earthquakes, fires, floods, etc. which are collectively known as external events. The methods described in this report have been developed under NRC sponsorship and represent, in many cases, both advancements and simplifications over techniques that have been used in past years. They also include the most up-to-date data bases on equipment seismic fragilities, fire occurrence frequencies and fire damageability thresholds. The methods described here are based on making full utilization of the power plant systems logic models developed in the internal events analyses. By making full use of the internal events models one obtains an external event analysis that is consistent both in nomenclature and in level of detail with the internal events analyses, and in addition, automatically includes all the appropriate random and tests/maintenance unavailabilities as appropriate. 50 refs., 9 figs., 11 tabs

  17. 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)

  18. 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

  19. Estimation of initiating event frequency for external flood events by extreme value theorem

    International Nuclear Information System (INIS)

    Chowdhury, Sourajyoti; Ganguly, Rimpi; Hari, Vibha

    2017-01-01

    External flood is an important common cause initiating event in nuclear power plants (NPPs). It may potentially lead to severe core damage (SCD) by first causing the failure of the systems required for maintaining the heat sinks and then by contributing to failures of engineered systems designed to mitigate such failures. The sample NPP taken here is twin 220 MWe Indian standard pressurized heavy water reactor (PHWR) situated inland. A comprehensive in-house Level-1 internal event PSA for full power had already been performed. External flood assessment was further conducted in area of external hazard risk assessment in response to post-Fukushima measures taken in nuclear industries. The present paper describes the methodology to calculate initiating event (IE) frequency for external flood events for the sample inland Indian NPP. General extreme value (GEV) theory based on maximum likelihood method (MLM) and order statistics approach (OSA) is used to analyse the rainfall data for the site. Thousand-year return level and necessary return periods for extreme rainfall are evaluated. These results along with plant-specific topographical calculations quantitatively establish that external flooding resulting from upstream dam break, river flooding and heavy rainfall (flash flood) would be unlikely for the sample NPP in consideration.

  20. 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

  1. Coordinated research programme on safety of RBMK type NPPs in relation to external events. V. 1. Working material

    International Nuclear Information System (INIS)

    1999-01-01

    The present volume is a collection of progress reports which have been submitted within the scope of the CRP on safety of RBMK type NPPs in relation to external events including seismic related papers and man-induced events (explosions and airplane crash). It includes papers concerned with experience related to RBMK equipment testing and calculations of seismic resistance, soil-structure interactions analysis, safety assurance, aircraft impact qualification and other external events for RBMK type NPP, seismic stability of NPPs in Eastern Europe, probabilistic assessment of NPP safety under aircraft impact, dynamic analysis of NPPs, screening of external hazards for NPP

  2. 10 CFR 72.94 - Design basis external man-induced events.

    Science.gov (United States)

    2010-01-01

    ... 10 Energy 2 2010-01-01 2010-01-01 false Design basis external man-induced events. 72.94 Section 72... WASTE Siting Evaluation Factors § 72.94 Design basis external man-induced events. (a) The region must be examined for both past and present man-made facilities and activities that might endanger the proposed...

  3. External event Probabilistic Risk Assessment for the High Flux Isotope Reactor (HFIR)

    International Nuclear Information System (INIS)

    Flanagan, G.F.; Johnson, D.H.; Buttemer, D.; Perla, H.F.; Chien, S.H.

    1989-01-01

    The High Flux Isotope Reactor (HFIR) is a high performance isotope production and research reactor which has been in operation at Oak Ridge National Laboratory (ORNL) since 1965. In late 1986 the reactor was shut down as a result of discovery of unexpected neutron embrittlement of the reactor vessel. In January of 1988 a level 1 Probabilistic Risk Assessment (PRA) (excluding external events) was published as part of the response to the many reviews that followed the shutdown and for use by ORNL to prioritize action items intended to upgrade the safety of the reactor. A conservative estimate of the core damage frequency initiated by internal events for HFIR was 3.11 x 10 -4 . In June 1989 a draft external events initiated PRA was published. The dominant contributions from external events came from seismic, wind, and fires. The overall external event contribution to core damage frequency is about 50% of the internal event initiated contribution and is dominated by seismic events

  4. Current status and issues of external event PSA for extreme natural hazards after Fukushima accident

    International Nuclear Information System (INIS)

    Choi, In-Kil; Hahm, Daegi; Kim, Min Kyu

    2014-01-01

    Extreme external events is emerged as significant risk contributor to the nuclear power plants after Fukushima Daiichi accident due to the catastrophic earthquake followed by great tsunami greater than a design basis. This accident shows that the extreme external events have the potential to simultaneously affect redundant and diverse safety systems and thereby induce common cause failure or common cause initiators. The probabilistic risk assessment methodology has been used for the risk assessment and safety improvement against the extreme natural hazards. The earthquake and tsunami hazard is an important issue for the nuclear industry in Korea. In this paper, the role and application of probabilistic safety assessment for the post Fukushima action will be introduced. For the evaluation of the extreme natural hazard, probabilistic seismic and tsunami hazard analysis is being performed for the safety enhancement. The research activity on the external event PSA and its interim results will be introduced with the issues to be solved in the future for the reliability enhancement of the risk analysis results. (authors)

  5. Joint Attributes and Event Analysis for Multimedia Event Detection.

    Science.gov (United States)

    Ma, Zhigang; Chang, Xiaojun; Xu, Zhongwen; Sebe, Nicu; Hauptmann, Alexander G

    2017-06-15

    Semantic attributes have been increasingly used the past few years for multimedia event detection (MED) with promising results. The motivation is that multimedia events generally consist of lower level components such as objects, scenes, and actions. By characterizing multimedia event videos with semantic attributes, one could exploit more informative cues for improved detection results. Much existing work obtains semantic attributes from images, which may be suboptimal for video analysis since these image-inferred attributes do not carry dynamic information that is essential for videos. To address this issue, we propose to learn semantic attributes from external videos using their semantic labels. We name them video attributes in this paper. In contrast with multimedia event videos, these external videos depict lower level contents such as objects, scenes, and actions. To harness video attributes, we propose an algorithm established on a correlation vector that correlates them to a target event. Consequently, we could incorporate video attributes latently as extra information into the event detector learnt from multimedia event videos in a joint framework. To validate our method, we perform experiments on the real-world large-scale TRECVID MED 2013 and 2014 data sets and compare our method with several state-of-the-art algorithms. The experiments show that our method is advantageous for MED.

  6. 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)

  7. 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

  8. Random and externally controlled occurrences of Dansgaard–Oeschger events

    Directory of Open Access Journals (Sweden)

    J. Lohmann

    2018-05-01

    Full Text Available Dansgaard–Oeschger (DO events constitute the most pronounced mode of centennial to millennial climate variability of the last glacial period. Since their discovery, many decades of research have been devoted to understand the origin and nature of these rapid climate shifts. In recent years, a number of studies have appeared that report emergence of DO-type variability in fully coupled general circulation models via different mechanisms. These mechanisms result in the occurrence of DO events at varying degrees of regularity, ranging from periodic to random. When examining the full sequence of DO events as captured in the North Greenland Ice Core Project (NGRIP ice core record, one can observe high irregularity in the timing of individual events at any stage within the last glacial period. In addition to the prevailing irregularity, certain properties of the DO event sequence, such as the average event frequency or the relative distribution of cold versus warm periods, appear to be changing throughout the glacial. By using statistical hypothesis tests on simple event models, we investigate whether the observed event sequence may have been generated by stationary random processes or rather was strongly modulated by external factors. We find that the sequence of DO warming events is consistent with a stationary random process, whereas dividing the event sequence into warming and cooling events leads to inconsistency with two independent event processes. As we include external forcing, we find a particularly good fit to the observed DO sequence in a model where the average residence time in warm periods are controlled by global ice volume and cold periods by boreal summer insolation.

  9. Random and externally controlled occurrences of Dansgaard-Oeschger events

    Science.gov (United States)

    Lohmann, Johannes; Ditlevsen, Peter D.

    2018-05-01

    Dansgaard-Oeschger (DO) events constitute the most pronounced mode of centennial to millennial climate variability of the last glacial period. Since their discovery, many decades of research have been devoted to understand the origin and nature of these rapid climate shifts. In recent years, a number of studies have appeared that report emergence of DO-type variability in fully coupled general circulation models via different mechanisms. These mechanisms result in the occurrence of DO events at varying degrees of regularity, ranging from periodic to random. When examining the full sequence of DO events as captured in the North Greenland Ice Core Project (NGRIP) ice core record, one can observe high irregularity in the timing of individual events at any stage within the last glacial period. In addition to the prevailing irregularity, certain properties of the DO event sequence, such as the average event frequency or the relative distribution of cold versus warm periods, appear to be changing throughout the glacial. By using statistical hypothesis tests on simple event models, we investigate whether the observed event sequence may have been generated by stationary random processes or rather was strongly modulated by external factors. We find that the sequence of DO warming events is consistent with a stationary random process, whereas dividing the event sequence into warming and cooling events leads to inconsistency with two independent event processes. As we include external forcing, we find a particularly good fit to the observed DO sequence in a model where the average residence time in warm periods are controlled by global ice volume and cold periods by boreal summer insolation.

  10. From IPE [individual plant examinations] to IPEEE [individual plant examination of external events

    International Nuclear Information System (INIS)

    Newton, I.M.

    1994-01-01

    In addition to doing individual plant examinations (IPEs) which assess risk to nuclear plants from internal factors, all US plants are now also required to analyse external events and submit an IPEEE (Individual Plant Examination of External Events). Specifically, the IPEEEs require an assessment of plant-specific risks from the following types of initiating events: seismic events; fire; wind; tornadoes; flooding; accidents involving transportation or nearby facilities, such as oil refineries. (author)

  11. IPEEE Review of other external events of the NPP Asco; Revision del IPEEE de sucesos externos de C.N. Asco

    Energy Technology Data Exchange (ETDEWEB)

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

    2011-07-01

    Within the process of maintaining and updating the risk analysis of the NPP Asco, results from the review of the vulnerability study of the plant against severe accidents caused by external success (Individual Plant Examination of External Events, IPEEE).

  12. A framework for the system-of-systems analysis of the risk for a safety-critical plant exposed to external events

    International Nuclear Information System (INIS)

    Zio, E.; Ferrario, E.

    2013-01-01

    We consider a critical plant exposed to risk from external events. We propose an original framework of analysis, which extends the boundaries of the study to the interdependent infrastructures which support the plant. For the purpose of clearly illustrating the conceptual framework of system-of-systems analysis, we work out a case study of seismic risk for a nuclear power plant embedded in the connected power and water distribution, and transportation networks which support its operation. The technical details of the systems considered (including the nuclear power plant) are highly simplified, in order to preserve the purpose of illustrating the conceptual, methodological framework of analysis. Yet, as an example of the approaches that can be used to perform the analysis within the proposed framework, we consider the Muir Web as system analysis tool to build the system-of-systems model and Monte Carlo simulation for the quantitative evaluation of the model. The numerical exercise, albeit performed on a simplified case study, serves the purpose of showing the opportunity of accounting for the contribution of the interdependent infrastructure systems to the safety of a critical plant. This is relevant as it can lead to considerations with respect to the decision making related to safety critical-issues. -- Highlights: ► We consider a critical plant exposed to risk from external events. ► We consider also the interdependent infrastructures that support the plant. ► We use Muir Web as system analysis tool to build the system-of-systems model. ► We use Monte Carlo simulation for the quantitative evaluation of the model. ► We find that the interdependent infrastructures should be considered as they can be a support for the critical plant safety

  13. Externalities - an analysis using the EU ExternE-results

    International Nuclear Information System (INIS)

    2003-10-01

    The EU project ExternE quantified the externalities for the different energy technologies. In this work, the ExternE results are used in a MARKAL-analysis for the Nordic countries. The analysis does not go into detail, but gives some interesting indications: The external costs are not fully covered in the Nordic energy systems, the present taxes and charges are not high enough. The emissions from the energy systems would be strongly reduced, if taxes/environmental charges were set at the level ExternE calculate. The emissions from power production would be reduced most. Renewable energy sources and natural gas dominate the energy systems in the ExternE case

  14. Review IPEEE C.N. external event Vandellos II; Revision del IPEEE de otros sucesos externos de C.N. Vandellos II

    Energy Technology Data Exchange (ETDEWEB)

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

    2010-07-01

    Within the process of maintaining and updating the risk analysis of CN Vandellos II, results from the review of the study of vulnerability of the plant against severe accidents caused by external events (Individual Plant Examination on Extornal Events, IPEEE).

  15. Identification and screening of hazards for the external event PRA - External hazard identification, screening and studies for a new plant site

    International Nuclear Information System (INIS)

    Hellander, Juho

    2014-01-01

    Fennovoima is constructing a new nuclear power plant on a greenfield site in Northern Finland. Various evaluations for site-specific hazards are needed to ensure sufficient plant design basis values, proper design solutions and to provide input for the PRA model. This paper presents the general process used in identifying the relevant site-specific external hazards. The applicable legislative requirements, guides and standards regarding external hazards and external event PRA shall be identified. Based on these, an initial comprehensive list of events should be compiled. The initial list shall be filtered to exclude irrelevant events. Events can be screened out if the probability is very low or if the consequences are only mild. Events with similar consequences should be combined. Events can be grouped in several ways, and in this paper the risks are categorized into events related to air, water bodies, ground and human behaviour. In addition, the simultaneously occurring combinations of events should be identified. The paper also summarizes some hazard studies already performed and required in the future in Fennovoima's project. A comprehensive study is ongoing related to earthquake risks. The study aims at identifying all relevant seismic sources and taking into account various expert opinions in seismic modelling. Also frazil ice and anchor ice studies are being performed to eliminate the risk of cooling water intake blockage due to ice. In addition, some other study areas are mentioned. This paper presented a list of Finnish and international guides and standards useful in evaluating external hazards. Also a methodology was presented to identify and screen site-specific hazards in a new nuclear power plant project. The screened list of relevant events for the Hanhikivi site requiring further studies was presented. Also the studies needed in different phases of a new nuclear power plant project were discussed. Some specific studies regarding earthquakes and

  16. The SKI-project External events - Phase 2. Estimation of fire frequencies per plant and per building

    International Nuclear Information System (INIS)

    Poern, K.

    1996-08-01

    The Swedish-Finnish handbook for initiating event frequencies, I-Book, does not contain any fire frequencies. This matter of fact is not defensible considering the substantial risk contribution caused by fires. In the PSAs performed hitherto the initiating fire frequencies have been determined from case to case. Because data are usually very scarce in these areas it is very important to develop unique definitions, to systematically utilize both international and national experiences and to establish an appropriate statistical estimation method. It is also important to present the accumulated experience such that it can be used for different purposes, not only within PSA but also in the concrete fire preventive work. During phase 1 of the project External Events an inventory was made of existing methods for probabilistic fire analysis in general. During phase 2 of the project it was decided to initialize the work on a complementary handbook, called X-Book, in order to encompass the frequencies of system external events, i.e. initiating events that are caused by events occurring outside the system boundaries. In Version 1 of the X-Book the attention is mainly focussed on the estimation of initiating fire frequencies, per plant and per building. This estimation is basically founded on reports that the power companies have collected for this specific purpose. This report describes the statistical model and method that have been used in the estimation process. The methodological results achieved may, possibly after some modification, be applicable also to other types of system external events

  17. AP1000R design robustness against extreme external events - Seismic, flooding, and aircraft crash

    International Nuclear Information System (INIS)

    Pfister, A.; Goossen, C.; Coogler, K.; Gorgemans, J.

    2012-01-01

    Both the International Atomic Energy Agency (IAEA) and the U.S. Nuclear Regulatory Commission (NRC) require existing and new nuclear power plants to conduct plant assessments to demonstrate the unit's ability to withstand external hazards. The events that occurred at the Fukushima-Dai-ichi nuclear power station demonstrated the importance of designing a nuclear power plant with the ability to protect the plant against extreme external hazards. The innovative design of the AP1000 R nuclear power plant provides unparalleled protection against catastrophic external events which can lead to extensive infrastructure damage and place the plant in an extended abnormal situation. The AP1000 plant is an 1100-MWe pressurized water reactor with passive safety features and extensive plant simplifications that enhance construction, operation, maintenance and safety. The plant's compact safety related footprint and protection provided by its robust nuclear island structures prevent significant damage to systems, structures, and components required to safely shutdown the plant and maintain core and spent fuel pool cooling and containment integrity following extreme external events. The AP1000 nuclear power plant has been extensively analyzed and reviewed to demonstrate that it's nuclear island design and plant layout provide protection against both design basis and extreme beyond design basis external hazards such as extreme seismic events, external flooding that exceeds the maximum probable flood limit, and malicious aircraft impact. The AP1000 nuclear power plant uses fail safe passive features to mitigate design basis accidents. The passive safety systems are designed to function without safety-grade support systems (such as AC power, component cooling water, service water, compressed air or HVAC). The plant has been designed to protect systems, structures, and components critical to placing the reactor in a safe shutdown condition within the steel containment vessel which is

  18. [Quality in Revision Arthroplasty: A Comparison between Claims Data Analysis and External Quality Assurance].

    Science.gov (United States)

    Wessling, M; Gravius, S; Gebert, C; Smektala, R; Günster, C; Hardes, J; Rhomberg, I; Koller, D

    2016-02-01

    External quality assurance for revisions of total knee arthroplasty (TKA) and total hip arthroplasty (THA) are carried out through the AQUA institute in Germany. Data are collected by the providers and are analyzed based on predefined quality indicators from the hospital stay in which the revision was performed. The present study explores the possibility to add routine data analysis to the existing external quality assurance (EQS). Differences between methods are displayed. The study aims to quantify the benefit of an additional analysis that allows patients to be followed up beyond the hospitalization itself. All persons insured in an AOK sickness fund formed the population for analysis. Revisions were identified using the same algorithm as the existing external quality assurance. Adverse events were defined according to the AQUA indicators for the years 2008 to 2011.The hospital stay in which the revision took place and a follow-up of 30 days were included. For re-operation and dislocation we also defined a 365 days interval for additional follow-up. The results were compared to the external quality control reports. Almost all indicators showed higher events in claims data analysis than in external quality control. Major differences are seen for dislocation (EQS SD: 1.87 vs. claims data [cd] SD: 2.06 %, cd+30 d: 2.91 %, cd+365 d: 7.27 %) and reoperation (hip revision: EQS SD: 5.88 % vs. claims data SD: 8.79 % cd+30 d: 9.82 %, cd+365 d: 15.0 %/knee revision: EQS SD: 3.21 % vs. claims data SD: 4.07 %, cd+30 d: 4.6 %, cd+365 d: 15.43 %). Claims data could show additional adverse events for all indicators after the initial hospital stay, rising to 77 % of all events. The number of adverse events differs between the existing external quality control and our claims data analysis. Claims data give the opportunity to complement existing methods of quality control though a longer follow-up, when many complications become evident. Georg

  19. Estimation of frequency of occurrence of extreme natural external events of very high intensity on the base of (non)available data - Estimation of frequency of rare natural external events of very high intensity on the base of (non)available data

    International Nuclear Information System (INIS)

    Holy, J.; Kolar, L.; Jaros, M.; Hladky, M.; Mlady, O.

    2014-01-01

    The relatively frequent natural external events are usually of minor safety importance, because the NPPs are, with a significant safety margin, constructed and operated to withstand the effects of them. Thus, risk analysis is typically devoted to the natural events of exceptional intensity, which mostly have not occurred up to now, but which still could happen with some low probability, but critical consequences. Since 'direct' plant specific data providing evidence about such events to occur is not at disposal, special data treatment and extrapolation methods have to be employed for frequency estimation. The paper summarizes possible approach to estimation of rate event frequency by means of extrapolation from available data and points out the potential problems and challenges encountered during the analysis. The general framework is commented in the presentation, regarding the effects of choice of probabilistic distribution (Gumbel distribution versus the others), methods of work with data records (To take out some observations and why?) and analysis of quality of input data sets (To mix the data sets from different sources or not? To use 'old' observations?) In the first part of the paper, the approach to creation of NPP Dukovany deterministic design basis regarding natural external events, which was used in past, is summarized. The second, major part of the paper, is devoted to involvement of the ideas of probabilistic safety assessment into safety assessment of external hazards, including such specific topics as addressing the quality of available data records, discussion on possible violation of common assumptions expected to be valid by the rules of statistical data analysis and the ways how to fix it, the choice of probabilistic distribution modeling data variability etc. The examples of results achieved for NPP Dukovany site in Czech republic are given in the final section. This paper represents a coordinated effort with participation of experts and staff

  20. Rare events in networks with internal and external noise

    Science.gov (United States)

    Hindes, J.; Schwartz, I. B.

    2017-12-01

    We study rare events in networks with both internal and external noise, and develop a general formalism for analyzing rare events that combines pair-quenched techniques and large-deviation theory. The probability distribution, shape, and time scale of rare events are considered in detail for extinction in the Susceptible-Infected-Susceptible model as an illustration. We find that when both types of noise are present, there is a crossover region as the network size is increased, where the probability exponent for large deviations no longer increases linearly with the network size. We demonstrate that the form of the crossover depends on whether the endemic state is localized near the epidemic threshold or not.

  1. The probabilistic risk analysis of external hazards of an interim storage for spent nuclear fuel in Olkiluoto

    International Nuclear Information System (INIS)

    Puukka, Tiia

    2014-01-01

    Due to natural disasters occurred in the world and the experiences perceived of the Fukushima nuclear accident, the particular knowledge of the role and influence of external hazards in the safety of interim storage of spent nuclear fuel has been emphasized. For that reason it is substantial that they are included in the probabilistic risk assessment (PRA) of the interim storage facility. This is also required by the Regulatory Guides issued by The Finnish Radiation and Nuclear Safety Authority STUK. To enhance safety culture and nuclear safety in Olkiluoto, The Finnish utility Teollisuuden Voima Oyj has recently completed an analysis of external natural (seismic events are studied as a separate analysis) and unintentional human-induced risks associated with the spent fuel pool cooling and decay heat removal systems as part of the full-scope PRA study for the interim storage of spent fuel (KPA store). The analysis had four goals to achieve: (1) to determine the definition of an initiating event in the context of the KPA store, (2) to identify all potential external hazards and hazard combinations, (3) to perform a qualitative screening analysis based on frequency-strength analysis and detailed plant responses analysis and (4) to model the hazards passed the screening analysis so that model can be used as a risk analysis tool in the risk informed decision making and operating procedures. The assessment carried out included the analysis of operation procedures of decay heat removal, the study of external hazards related initiating events included in the PRA of the OL1 and OL2 nuclear power plants and their dependencies on the initiating events of the KPA store. All external hazards related initiating events were modeled using fault tree linking method. The main result and conclusion of this study was that using the screening analysis, initiating events caused by external hazards that could lead to leakage of the spent fuel pools or that could pose a threat to the

  2. AP1000{sup R} design robustness against extreme external events - Seismic, flooding, and aircraft crash

    Energy Technology Data Exchange (ETDEWEB)

    Pfister, A.; Goossen, C.; Coogler, K.; Gorgemans, J. [Westinghouse Electric Company LLC, 1000 Westinghouse Drive, Cranberry Township, PA 16066 (United States)

    2012-07-01

    Both the International Atomic Energy Agency (IAEA) and the U.S. Nuclear Regulatory Commission (NRC) require existing and new nuclear power plants to conduct plant assessments to demonstrate the unit's ability to withstand external hazards. The events that occurred at the Fukushima-Dai-ichi nuclear power station demonstrated the importance of designing a nuclear power plant with the ability to protect the plant against extreme external hazards. The innovative design of the AP1000{sup R} nuclear power plant provides unparalleled protection against catastrophic external events which can lead to extensive infrastructure damage and place the plant in an extended abnormal situation. The AP1000 plant is an 1100-MWe pressurized water reactor with passive safety features and extensive plant simplifications that enhance construction, operation, maintenance and safety. The plant's compact safety related footprint and protection provided by its robust nuclear island structures prevent significant damage to systems, structures, and components required to safely shutdown the plant and maintain core and spent fuel pool cooling and containment integrity following extreme external events. The AP1000 nuclear power plant has been extensively analyzed and reviewed to demonstrate that it's nuclear island design and plant layout provide protection against both design basis and extreme beyond design basis external hazards such as extreme seismic events, external flooding that exceeds the maximum probable flood limit, and malicious aircraft impact. The AP1000 nuclear power plant uses fail safe passive features to mitigate design basis accidents. The passive safety systems are designed to function without safety-grade support systems (such as AC power, component cooling water, service water, compressed air or HVAC). The plant has been designed to protect systems, structures, and components critical to placing the reactor in a safe shutdown condition within the steel

  3. Preliminary perspectives gaines from individual plant examination of external events (IPEEE) seismic and fire submittal review

    International Nuclear Information System (INIS)

    Chen, J.T.; Connell, E.; Chokshi, N.

    1997-01-01

    As a result of the U.S. Nuclear Regulatory Commission (USNRC) initiated Individual plant Examination of External Events (IPEEE) program, every operating nuclear power reactor in the United States has performed an assessment of severe accident due to external events. This paper provides a summary of the preliminary insights gained through the review of 24 IPEEE submittals

  4. 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.

  5. Recent developments in the external hazard risk assessment in Ukraine

    International Nuclear Information System (INIS)

    2000-01-01

    Ukrainian legislation prescribes safety analysis reports for all operating and future NPPs. Apart from main report they must include: safety analysis supplement; design basis accident analysis; beyond design basis accident analysis; probabilistic safety assessment (PSA); technical; substantiation of safety. Regulatory requirements to PSA contents cover the criteria for core damage frequency and large radioactive release frequency. Initiating events taken into account are internal events; internal hazards and external hazards. External hazards to be considered are seismic events, external fires, external floods, extreme ambient temperatures, aircraft crashes, etc. Current status of PSA development is related to operating WWER-440 and WWER-1000 NPPs and NPPs under construction. This presentation describes in detail the external hazard risk assessment for South Ukraine including methodology applied and expected future activities

  6. External hazards analysis approach to level 1 PSA of Mochovce NPP - Slovakia

    International Nuclear Information System (INIS)

    Stojka, Tibor

    2000-01-01

    Analyses of external events had been first time performed at the design stage of the Mochovce NPP showing sufficiently low contribution of external hazards to core damage frequency. But, based on IAEA document 'Safety problems of WWER-440/213 NPPs and the categorization' (IAEA-EBP-WWER-03, 1996), the need of new reassessment arose due to discrepancy of some origin recommendations in compare with present IAEA ones. Mochovce NPP Nuclear Safety Improvements Program elaborated at the same time included the IAEA recommendations and following improvements were proposed to perform in context of external events. 1. Seismic project and new locality seismic evaluation This safety improvement includes also some 'on site' technical improvements in seismic stability of structures and equipment. 2. Unit specific analyses of extreme meteorologic conditions. This safety improvement focuses on impact of feasible extreme conditions on NPP systems caused by rain, snow and hail storms, frost, winds, low and high temperatures. 3. Analyses of external hazards caused by humans. In this safety improvement were specified: feasible sources of explosions; analyses of hydrogen, gas and propane-calor gas depots; air crash risk. The results of these implemented safety improvements were considered in the PSA study. The External hazards analysis is also part of Level 1 PSA Mochovce NPP performed by PSA Department of VUJE Trnava Inc., Engineering, Design and Research Organization, Slovakia. Some partial analyses are performed in cooperation with following companies DS and S - SAIC, USA and Geophysical Institute Academy of Science, Slovakia Relko, Slovakia. Basic documents are: NUREG/CR-2300 'PRA Procedures Guide - A Guide to the Performance of Probabilistic Risk Assessments for Nuclear Power Plants' and IAEA SS No. 50-P-7 'Treatment of External Hazards in PSA for NPPs. The external hazards analysis consists of following parts: 1. Geography and plant locality; 2. Nearby industry; 3. Extreme

  7. Analysis of area events as part of probabilistic safety assessment for Romanian TRIGA SSR 14 MW reactor

    International Nuclear Information System (INIS)

    Mladin, D.; Stefan, I.

    2005-01-01

    The international experience has shown that the external events could be an important contributor to plant/ reactor risk. For this reason such events have to be included in the PSA studies. In the context of PSA for nuclear facilities, external events are defined as events originating from outside the plant, but with the potential to create an initiating event at the plant. To support plant safety assessment, PSA can be used to find methods for identification of vulnerable features of the plant and to suggest modifications in order to mitigate the impact of external events or the producing of initiating events. For that purpose, probabilistic assessment of area events concerning fire and flooding risk and impact is necessary. Due to the relatively large power level amongst research reactors, the approach to safety analysis of Romanian 14 MW TRIGA benefits from an ongoing PSA project. In this context, treatment of external events should be considered. The specific tasks proposed for the complete evaluation of area event analysis are: identify the rooms important for facility safety, determine a relative area event risk index for these rooms and a relative area event impact index if the event occurs, evaluate the rooms specific area event frequency, determine the rooms contribution to reactor hazard state frequencies, analyze power supply and room dependencies of safety components (as pumps, motor operated valves). The fire risk analysis methodology is based on Berry's method [1]. This approach provides a systematic procedure to carry out a relative index of different rooms. The factors, which affect the fire probability, are: personal presence in the room, number and type of ignition sources, type and area of combustibles, fuel available in the room, fuel location, and ventilation. The flooding risk analysis is based on the amount of piping in the room. For accuracy of the information regarding piping a facility walk-about is necessary. In case of flooding risk

  8. Effects of hypnagogic imagery on the event-related potential to external tone stimuli.

    Science.gov (United States)

    Michida, Nanae; Hayashi, Mitsuo; Hori, Tadao

    2005-07-01

    The purpose of this study was to examine the influence of hypnagogic imagery on the information processes of external tone stimuli during the sleep onset period with the use of event-related potentials. Event-related potentials to tone stimuli were compared between conditions with and without the experience of hypnagogic imagery. To control the arousal level when the tone was presented, a certain criterion named the electroencephalogram stage was used. Stimuli were presented at electroencephalogram stage 4, which was characterized by the appearance of a vertex sharp wave. Data were collected in the sleep laboratory at Hiroshima University. Eleven healthy university and graduate school students participated in the study. N/A. Experiments were performed at night. Reaction times to tone stimuli were measured, and only trials with shorter reaction times than 5000 milliseconds were analyzed. Electroencephalograms were recorded from Fz, Cz, Pz, Oz, T5 and T6. There were no differences in reaction times and electroencephalogram spectra between the conditions of with and without hypnagogic imagery. These results indicated that the arousal levels were not different between the 2 conditions. On the other hand, the N550 amplitude of the event-related potentials in the imagery condition was lower than in the no-imagery condition. The decrease in the N550 amplitude in the imagery condition showed that experiences of hypnagogic imagery exert some influence on the information processes of external tone stimuli. It is possible that the processing of hypnagogic imagery interferes with the processing of external stimuli, lowering the sensitivity to external stimuli.

  9. ASAMPSA-E guidance for level 2 PSA Volume 2. Implementing external Events modelling in Level 2 PSA

    International Nuclear Information System (INIS)

    Cazzoli, E.; Vitazkova, J.; Loeffler, H.; Burgazzi, L.

    2016-01-01

    The objective of the present document is to provide guidance on the implementation of external events into an 'extended' L2 PSA. It has to be noted that L2 PSA addresses issues beginning with fuel degradation and ending with the release of radionuclides into the environment. Therefore, the present document may touch upon, but does not evaluate explicitly issues that involve events or phenomena which occur before the fuel begins to degrade. Following the accident at Fukushima Dai-ichi, the nuclear safety community has realized that much attention should be given to the areas of operator interventions and accidents that may develop at the same time in more than one unit if they are initiated by one or more common external events. For this reason and to fulfill the PSA end-users' wish list (as reflected by an ASAMPSA-E survey), the attention is mostly focused on interface between L1 and L2 PSA, fragility analysis, human response analysis and some consideration is given to L2 PSA modeling of severe accidents for multiple unit sites, even though it is premature to provide extensive guidance in this area. The following recommendations, mentioned in various sections within this document, are summarized here: 1. Vulnerability/fragility analyses should be performed with respect to all external hazards and all structures, systems and components potentially affected that could be relevant to L2 PSA, 2. Importance should be given to the assessment of human performance following extreme external events; for extreme circumstances with high stress level, low confidence is justified for SAM human interventions and for such conditions, human interventions could be analyzed as sensitivity cases only in L2 PSA, 3. Results presentation should include assessment of total risk measures compared with risk targets able to assess all contributions to the risk and to judge properly the safety, 4. Total risk measures shall be associated to appropriate information on all

  10. The external leadership of self-managing teams: intervening in the context of novel and disruptive events.

    Science.gov (United States)

    Morgeson, Frederick P

    2005-05-01

    Relatively little empirical research has been conducted on external leaders of self-managing teams. The integration of functional leadership theory with research on team routines suggests that leaders can intervene in teams in several different ways, and the effectiveness of this intervention depends on the nature of the events the team encounters. External team leaders from 3 organizations first described a series of events (N=117), and leaders and team members then completed surveys to quantitatively describe the events. Results indicated that leader preparation and supportive coaching were positively related to team perceptions of leader effectiveness, with preparation becoming more strongly related to effectiveness as event novelty increased. More active leader intervention activities (active coaching and sense making) were negatively related to satisfaction with leadership yet were positively related to effectiveness as events became more disruptive.

  11. Environmental conditions using thermal-hydraulics computer code GOTHIC for beyond design basis external events

    International Nuclear Information System (INIS)

    Pleskunas, R.J.

    2015-01-01

    In response to the Fukushima Dai-ichi beyond design basis accident in March 2011, the Nuclear Regulatory Commission (NRC) issued Order EA-12-049, 'Issuance of Order to Modify Licenses with Regard to Requirements for Mitigation Strategies Beyond-Design-Basis-External-Events'. To outline the process to be used by individual licensees to define and implement site-specific diverse and flexible mitigation strategies (FLEX) that reduce the risks associated with beyond design basis conditions, Nuclear Energy Institute document NEI 12-06, 'Diverse and Flexible Coping Strategies (FLEX) Implementation Guide', was issued. A beyond design basis external event (BDBEE) is postulated to cause an Extended Loss of AC Power (ELAP), which will result in a loss of ventilation which has the potential to impact room habitability and equipment operability. During the ELAP, portable FLEX equipment will be used to achieve and maintain safe shutdown, and only a minimal set of instruments and controls will be available. Given these circumstances, analysis is required to determine the environmental conditions in several vital areas of the Nuclear Power Plant. The BDBEE mitigating strategies require certain room environments to be maintained such that they can support the occupancy of personnel and the functionality of equipment located therein, which is required to support the strategies associated with compliance to NRC Order EA-12-049. Three thermal-hydraulic analyses of vital areas during an extended loss of AC power using the GOTHIC computer code will be presented: 1) Safety-related pump and instrument room transient analysis; 2) Control Room transient analysis; and 3) Auxiliary/Control Building transient analysis. GOTHIC (Generation of Thermal-Hydraulic Information for Containment) is a general purpose thermal-hydraulics software package for the analysis of nuclear power plant containments, confinement buildings, and system components. It is a volume/path/heat sink

  12. 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.

  13. Estimation of integrated public risks for nonseismic external events affecting the Savannah River Site

    International Nuclear Information System (INIS)

    Durant, W.S.; robinette, R.J.; Kirchner, J.R.

    1994-03-01

    In essence, this study was envisioned as the ''combination'' of existing accident dose and risk calculations from safety analyses of individual facilities. However, because of the extended time period over which the safety analyses were prepared, calculational assumptions and methodologies differed between the analyses. The scope of this study therefore included the standardization of assumptions and calculations as necessary to insure that the analytical logic was consistent for all the facilities. Each of the nonseismic external events considered in the analyses are addressed in individual sections in this report. In Section 2, extreme straight-line winds are examined. Section 3 addresses tornadoes, and Section 4 addresses other external events [floods, other extreme weather events (lightning, hail, and extremes in temperature or precipitation), vehicle impact, accidents involving adjacent facilities, aircraft impact, and meteorite impact]. Section 5 provides a summary of the general conclusions of the report

  14. Quantification of risk considering external events on the change of allowed outage time and the preventive maintenance during power operation

    Energy Technology Data Exchange (ETDEWEB)

    Kang, D. J.; Kim, K. Y.; Yang, J. E

    2001-03-01

    In this study, for the major safety systems of Ulchin Units 3/4, we quantify the risk on the change of AOT and the PM during power operation to identify the effects on the results of external events PSA when nuclear power plant changes such as allowed outage time are requested. The systems for which the risks on the change of allowed outage time are quantified are High Pressure Safety Injection System (HPSIS), Containment Spray System (CSS), and Emergency Diesel Generator (EDG). The systems for which the risks on the PM during power operation are Low Pressure Safety Injection System (LPSIS), CSS, EDG, Essential Service Water System (ESWS). Following conclusions can be obtained through this study: 1)The increase of core damage frequency ({delta}CDF) on the change of AOT and the conditional core damage probability (CCDP) on the on-line PM of each system are differently quantified according to the cases of considering only internal events or only external events. . 2)It is expected that the quantification of risk including internal and external events is advantageous for the licensee of NPP if the regulatory acceptance criteria for the technical specification changes are relatively set up. However, it is expected to be disadvantageous for the licensee if the acceptance criteria are absolutely set up. 3)It is expected that the conduction on the quantification of only a fire event is sufficient when the quantification of external events PSA model is required for the plant changes of Korea Standard NPPs. 4)It is expected that the quantification of the increase of core damage frequency and the incremental conditional core damage probability on technical specification changes are not needed if the quantification results of those considering only internal events are below regulatory acceptance criteria and the external events PSA results are not greatly affected by the system availability. However, it is expected that the quantification of risk considering external events

  15. Quantification of risk considering external events on the change of allowed outage time and the preventive maintenance during power operation

    International Nuclear Information System (INIS)

    Kang, D. J.; Kim, K. Y.; Yang, J. E.

    2001-03-01

    In this study, for the major safety systems of Ulchin Units 3/4, we quantify the risk on the change of AOT and the PM during power operation to identify the effects on the results of external events PSA when nuclear power plant changes such as allowed outage time are requested. The systems for which the risks on the change of allowed outage time are quantified are High Pressure Safety Injection System (HPSIS), Containment Spray System (CSS), and Emergency Diesel Generator (EDG). The systems for which the risks on the PM during power operation are Low Pressure Safety Injection System (LPSIS), CSS, EDG, Essential Service Water System (ESWS). Following conclusions can be obtained through this study: 1)The increase of core damage frequency (ΔCDF) on the change of AOT and the conditional core damage probability (CCDP) on the on-line PM of each system are differently quantified according to the cases of considering only internal events or only external events. . 2)It is expected that the quantification of risk including internal and external events is advantageous for the licensee of NPP if the regulatory acceptance criteria for the technical specification changes are relatively set up. However, it is expected to be disadvantageous for the licensee if the acceptance criteria are absolutely set up. 3)It is expected that the conduction on the quantification of only a fire event is sufficient when the quantification of external events PSA model is required for the plant changes of Korea Standard NPPs. 4)It is expected that the quantification of the increase of core damage frequency and the incremental conditional core damage probability on technical specification changes are not needed if the quantification results of those considering only internal events are below regulatory acceptance criteria and the external events PSA results are not greatly affected by the system availability. However, it is expected that the quantification of risk considering external events on

  16. Apical External Root Resorption and Repair in Orthodontic Tooth Movement: Biological Events.

    Science.gov (United States)

    Feller, Liviu; Khammissa, Razia A G; Thomadakis, George; Fourie, Jeanine; Lemmer, Johan

    2016-01-01

    Some degree of external root resorption is a frequent, unpredictable, and unavoidable consequence of orthodontic tooth movement mediated by odontoclasts/cementoclasts originating from circulating precursor cells in the periodontal ligament. Its pathogenesis involves mechanical forces initiating complex interactions between signalling pathways activated by various biological agents. Resorption of cementum is regulated by mechanisms similar to those controlling osteoclastogenesis and bone resorption. Following root resorption there is repair by cellular cementum, but factors mediating the transition from resorption to repair are not clear. In this paper we review some of the biological events associated with orthodontically induced external root resorption.

  17. Apical External Root Resorption and Repair in Orthodontic Tooth Movement: Biological Events

    Directory of Open Access Journals (Sweden)

    Liviu Feller

    2016-01-01

    Full Text Available Some degree of external root resorption is a frequent, unpredictable, and unavoidable consequence of orthodontic tooth movement mediated by odontoclasts/cementoclasts originating from circulating precursor cells in the periodontal ligament. Its pathogenesis involves mechanical forces initiating complex interactions between signalling pathways activated by various biological agents. Resorption of cementum is regulated by mechanisms similar to those controlling osteoclastogenesis and bone resorption. Following root resorption there is repair by cellular cementum, but factors mediating the transition from resorption to repair are not clear. In this paper we review some of the biological events associated with orthodontically induced external root resorption.

  18. Market response to external events and interventions in spherical minority games

    International Nuclear Information System (INIS)

    Papadopoulos, P; Coolen, A C C

    2008-01-01

    We solve the dynamics of large spherical minority games (MG) in the presence of non-negligible time-dependent external contributions to the overall market bid. The latter represent the actions of market regulators or other major natural or political events that impact on the market. In contrast to non-spherical MGs, the spherical formulation allows one to derive closed dynamical order parameter equations in an explicit form and work out the market's response to such events fully analytically. We focus on a comparison between the response to stationary versus oscillating market interventions, and reveal profound and partially unexpected differences in terms of transition lines and the volatility

  19. Hydropower externalities: A meta-analysis

    International Nuclear Information System (INIS)

    Mattmann, Matteo; Logar, Ivana; Brouwer, Roy

    2016-01-01

    This paper presents a meta-analysis of existing research related to the economic valuation of the external effects of hydropower. A database consisting of 81 observations derived from 29 studies valuing the non-market impacts of hydropower electricity generation is constructed with the main aim to quantify and explain the economic values for positive and negative hydropower externalities. Different meta-regression model specifications are used to test the robustness of significant determinants of non-market values, including different types of hydropower impacts. The explanatory and predictive power of the estimated models is relatively high. Whilst controlling for sample and study characteristics, we find significant evidence for public aversion towards deteriorations of landscape, vegetation and wildlife caused by hydropower projects. There is however only weak evidence of willingness to pay for mitigating these effects. The main positive externality of hydropower generation, the avoidance of greenhouse gas emission, positively influences welfare estimates when combined with the share of hydropower in national energy production. Sensitivity to scope is detected, but not linked to specific externalities or non-market valuation methods. - Highlights: • A global meta-analysis of valuation studies of hydropower externalities is presented. • Positive and negative externalities are distinguished. • Welfare losses due to environmental deteriorations outweigh gains of GHG reductions. • There is only weak evidence of public WTP for mitigating negative externalities. • The non-market values of hydropower externalities are sensitive to scope.

  20. The Interactive Effects of Stressful Family Life Events and Cortisol Reactivity on Adolescent Externalizing and Internalizing Behaviors

    Science.gov (United States)

    Steeger, Christine M.; Cook, Emily C.; Connell, Christian M.

    2016-01-01

    This study investigated the associations between stressful family life events and adolescent externalizing and internalizing behaviors, and the interactive effects of family life events and cortisol reactivity on problem behaviors. In a sample of 100 mothers and their adolescents (M age = 15.09; SD age = 0.98; 68% girls), adolescent cortisol reactivity was measured in response to a mother-adolescent conflict interaction task designed to elicit a stress response. Mothers reported on measures of family life events and adolescent problem behaviors. Results indicated that a heightened adolescent cortisol response moderated the relations between stressful family life events and both externalizing and internalizing behaviors. Results support context-dependent theoretical models, suggesting that for adolescents with higher cortisol reactivity (compared to those with lower cortisol reactivity), higher levels of stressful family life events were associated with greater problem behaviors, whereas lower levels of stressful family life events were related to fewer problem behaviors. PMID:26961703

  1. 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)

  2. 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)

  3. 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

  4. 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

  5. External flood probabilistic safety analysis of a coastal NPP

    International Nuclear Information System (INIS)

    Pisharady, Ajai S.; Chakraborty, M.K.; Acharya, Sourav; Roshan, A.D.; Bishnoi, L.R.

    2015-01-01

    External events pose a definitive challenge to safety of NPP, solely due to their ability to induce common cause failures. Flooding incidents at Le Blayais NPP, France, Fort Calhoun NPP, USA and Fukushima Daiichi have pointed to the importance of external flooding as an important contributor to NPP risk. A methodology developed for external flood PSA of a coastal NPP vulnerable to flooding due to tsunami, cyclonic storm and intense local precipitation is presented in this paper. Different tasks for EFPSA has been identified along with general approach for completing each task

  6. 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

  7. Risk analysis of external radiation therapy

    International Nuclear Information System (INIS)

    Arvidsson, Marcus

    2011-09-01

    External radiation therapy is carried out via a complex treatment process in which many different groups of staff work together. Much of the work is dependent on and in collaboration with advanced technical equipment. The purpose of the research task has been to identify a process for external radiation therapy and to identify, test and analyze a suitable method for performing risk analysis of external radiation therapy

  8. The EPR-a comprehensive design concept against external events

    International Nuclear Information System (INIS)

    Waas, U.; Stoll, U.

    2005-01-01

    The main objective of design provisions against external hazards is to ensure that the safety functions required to bring the plant to safe shutdown are not inadmissible affected. In the design of the EPR particular attention was paid to the following external hazards: Earthquake, Airplane crash, Explosion pressure wave. The design concept for these events is discussed below. The standard EPR covers a large range of possible site conditions, the design earthquake enveloping safe shutdown earthquakes (SSE) to be expected for potential sites. The Basic Design was developed for the seismic loads given in the European Utility Requirements with a horizontal free field Peak Ground Acceleration (PGA) for all site conditions of 0.25 g. The seismic protection is based on a deterministic design approach, with the intention of ensuring the safety functions in case of SSE. The loads for the design basis airplane crash and - if required - for the design extension airplane crash are defined depending on site specific requirements. For the design basis airplane crash as defined in Finland the safety goals are fulfilled for postulated single failure and preventive maintenance as well as for specific unlikely scenarios with local impacts where one redundant train is assumed to be lost. For the design extension airplane crash no single failure and preventive maintenance are assumed. Reactor building (RB), fuel building (FB), safeguard building (SB) 2 and 3 are protected by design against airplane crash. The common base mat of the RB, FB and SBs ensures global stability. To avoid penetration the wall thickness of the outer building structures of RB, FB and SB2/3 is set at 1.80 m (result of an optimization process). To rule out major induced vibrations due to airplane crash the inner building structures are decoupled from the outer walls. The SB 1 and SB4, the main steam and feedwater valve compartments, the diesel buildings and the service water pump buildings are protected against

  9. 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)

  10. Wind power externalities: A meta-analysis

    NARCIS (Netherlands)

    Mattmann, M.; Logar, I.; Brouwer, R.

    2016-01-01

    This study presents the first quantitative meta-analysis of the non-market valuation literature on the external effects associated with wind power production. A data set of 60 observations drawn from 32 studies is constructed. The relative economic values of different types of externalities as well

  11. Comorbidity in illness-induced posttraumatic stress disorder versus posttraumatic stress disorder due to external events in a nationally representative study.

    Science.gov (United States)

    Sommer, Jordana L; Mota, Natalie; Edmondson, Donald; El-Gabalawy, Renée

    2018-05-10

    The current study compared physical and mental health characteristics and quality of life of illness-induced posttraumatic stress disorder (PTSD) versus those with PTSD due to external traumatic events in a population-based sample. PTSD was assessed with the Alcohol Use Disorder and Associated Disabilities Interview Schedule (AUDADIS-5) using DSM-5 criteria in the 2012-2013 National Epidemiologic Survey on Alcohol and Related Conditions. Participants with past-year PTSD (n = 1779) were categorized into two groups: illness-induced (6.5%) and other trauma-induced PTSD (92.9%) based on index trauma. Group differences in physical health, mental health, and quality of life were estimated using multiple logistic and linear regressions with adjustment for demographics and medical morbidity. Compared to PTSD due to external events, illness-induced PTSD had higher rates of life-threatening illness in the past year. Illness-induced PTSD compared to PTSD due to external events was associated with reduced odds of depressive/bipolar disorders and antisocial personality disorder, but increased odds of cannabis use disorder. The groups did not differ on quality of life after accounting for medical morbidity. Illness-induced PTSD is common among American adults and has a similar impact on quality of life as PTSD due to external events, but may have distinct mental health correlates. Copyright © 2018 Elsevier Inc. All rights reserved.

  12. Accident analyses in nuclear power plants following external initiating events and in the shutdown state. Final report

    International Nuclear Information System (INIS)

    Loeffler, Horst; Kowalik, Michael; Mildenberger, Oliver; Hage, Michael

    2016-06-01

    The work which is documented here provides the methodological basis for improvement of the state of knowledge for accident sequences after plant external initiating events and for accident sequences which begin in the shutdown state. The analyses have been done for a PWR and for a BWR reference plant. The work has been supported by the German federal ministry BMUB under the label 3612R01361. Top objectives of the work are: - Identify relevant event sequences in order to define characteristic initial and boundary conditions - Perform accident analysis of selected sequences - Evaluate the relevance of accident sequences in a qualitative way The accident analysis is performed with the code MELCOR 1.8.6. The applied input data set has been significantly improved compared to previous analyses. The event tree method which is established in PSA level 2 has been applied for creating a structure for a unified summarization and evaluation of the results from the accident analyses. The computer code EVNTRE has been applied for this purpose. In contrast to a PSA level 2, the branching probabilities of the event tree have not been determined with the usual accuracy, but they are given in an approximate way only. For the PWR, the analyses show a considerable protective effect of the containment also in the case of beyond design events. For the BWR, there is a rather high probability for containment failure under core melt impact, but nevertheless the release of radionuclides into the environment is very limited because of plant internal retention mechanisms. This report concludes with remarks about existing knowledge gaps and with regard to core melt sequences, and about possible improvements of the plant safety.

  13. Light Water Reactor Sustainability Program Industry Application External Hazard Analyses Problem Statement

    Energy Technology Data Exchange (ETDEWEB)

    Szilard, Ronaldo Henriques [Idaho National Lab. (INL), Idaho Falls, ID (United States); Coleman, Justin [Idaho National Lab. (INL), Idaho Falls, ID (United States); Smith, Curtis L. [Idaho National Lab. (INL), Idaho Falls, ID (United States); Prescott, Steven [Idaho National Lab. (INL), Idaho Falls, ID (United States); Kammerer, Annie [Annie Kammerer Consulting, Rye, NH (United States); Youngblood, Robert [Idaho National Lab. (INL), Idaho Falls, ID (United States); Pope, Chad [Idaho State Univ., Pocatello, ID (United States)

    2015-07-01

    Risk-Informed Margin Management Industry Application on External Events. More specifically, combined events, seismically induced external flooding analyses for a generic nuclear power plant with a generic site soil, and generic power plant system and structure. The focus of this report is to define the problem above, set up the analysis, describe the methods to be used, tools to be applied to each problem, and data analysis and validation associated with the above.

  14. Component external leakage and rupture frequency estimates

    International Nuclear Information System (INIS)

    Eide, S.A.; Khericha, S.T.; Calley, M.B.; Johnson, D.A.; Marteeny, M.L.

    1991-11-01

    In order to perform detailed internal flooding risk analyses of nuclear power plants, external leakage and rupture frequencies are needed for various types of components - piping, valves, pumps, flanges, and others. However, there appears to be no up-to-date, comprehensive source for such frequency estimates. This report attempts to fill that void. Based on a comprehensive search of Licensee Event Reports (LERs) contained in Nuclear Power Experience (NPE), and estimates of component populations and exposure times, component external leakage and rupture frequencies were generated. The remainder of this report covers the specifies of the NPE search for external leakage and rupture events, analysis of the data, a comparison with frequency estimates from other sources, and a discussion of the results

  15. Screening Analysis of Criticality Features, Events, and Processes for License Application

    International Nuclear Information System (INIS)

    J.A. McClure

    2004-01-01

    This report documents the screening analysis of postclosure criticality features, events, and processes. It addresses the probability of criticality events resulting from degradation processes as well as disruptive events (i.e., seismic, rock fall, and igneous). Probability evaluations are performed utilizing the configuration generator described in ''Configuration Generator Model'', a component of the methodology from ''Disposal Criticality Analysis Methodology Topical Report''. The total probability per package of criticality is compared against the regulatory probability criterion for inclusion of events established in 10 CFR 63.114(d) (consider only events that have at least one chance in 10,000 of occurring over 10,000 years). The total probability of criticality accounts for the evaluation of identified potential critical configurations of all baselined commercial and U.S. Department of Energy spent nuclear fuel waste form and waste package combinations, both internal and external to the waste packages. This criticality screening analysis utilizes available information for the 21-Pressurized Water Reactor Absorber Plate, 12-Pressurized Water Reactor Absorber Plate, 44-Boiling Water Reactor Absorber Plate, 24-Boiling Water Reactor Absorber Plate, and the 5-Defense High-Level Radioactive Waste/U.S. Department of Energy Short waste package types. Where defensible, assumptions have been made for the evaluation of the following waste package types in order to perform a complete criticality screening analysis: 21-Pressurized Water Reactor Control Rod, 5-Defense High-Level Radioactive Waste/U.S. Department of Energy Long, and 2-Multi-Canister Overpack/2-Defense High-Level Radioactive Waste package types. The inputs used to establish probabilities for this analysis report are based on information and data generated for the Total System Performance Assessment for the License Application, where available. This analysis report determines whether criticality is to be

  16. Extremely intense (SML ≤–2500 nT substorms: isolated events that are externally triggered?

    Directory of Open Access Journals (Sweden)

    B. T. Tsurutani

    2015-05-01

    Full Text Available We examine particularly intense substorms (SML ≤–2500 nT, hereafter called "supersubstorms" or SSS events, to identify their nature and their magnetic storm dependences. It is found that these intense substorms are typically isolated events and are only loosely related to magnetic storms. SSS events can occur during super (Dst ≤–250 nT and intense (−100 nT ≥ Dst >–250 magnetic storms. SSS events can also occur during nonstorm (Dst ≥–50 nT intervals. SSSs are important because the strongest ionospheric currents will flow during these events, potentially causing power outages on Earth. Several SSS examples are shown. SSS events appear to be externally triggered by small regions of very high density (~30 to 50 cm−3 solar wind plasma parcels (PPs impinging upon the magnetosphere. Precursor southward interplanetary magnetic fields are detected prior to the PPs hitting the magnetosphere. Our hypothesis is that these southward fields input energy into the magnetosphere/magnetotail and the PPs trigger the release of the stored energy.

  17. iROCS: Integrated accident management framework for coping with beyond-design-basis external events

    International Nuclear Information System (INIS)

    Kim, Jaewhan; Park, Soo-Yong; Ahn, Kwang-Il; Yang, Joon-Eon

    2016-01-01

    Highlights: • An integrated mitigating strategy to cope with extreme external events, iROCS, is proposed. • The strategy aims to preserve the integrity of the reactor vessel as well as core cooling. • A case study for an extreme damage state is performed to assess the effectiveness and feasibility of candidate mitigation strategies under an extreme event. - Abstract: The Fukushima Daiichi accident induced by the Great East Japan earthquake and tsunami on March 11, 2011, poses a new challenge to the nuclear society, especially from an accident management viewpoint. This paper presents a new accident management framework called an integrated, RObust Coping Strategy (iROCS) to cope with beyond-design-basis external events (BDBEEs). The iROCS approach is characterized by classification of various plant damage conditions (PDCs) that might be impacted by BDBEEs and corresponding integrated coping strategies for each of PDCs, aiming to maintain and restore core cooling (i.e., to prevent core damage) and to maintain the integrity of the reactor pressure vessel if it is judged that core damage may not be preventable in view of plant conditions. From a case study for an extreme damage condition, it showed that candidate accident management strategies should be evaluated from the viewpoint of effectiveness and feasibility against accident scenarios and extreme damage conditions of the site, especially when employing mobile or portable equipment under BDBEEs within the limited time available to achieve desired goals such as prevention of core damage as well as a reactor vessel failure.

  18. The EPR-a comprehensive design concept against external events

    International Nuclear Information System (INIS)

    Stoll, U.; Waas, U.

    2006-01-01

    The main objective of design provisions against external hazards is to ensure that the safety functions required to bring the plant to safe shutdown are not inadmissibly affected by any external hazards that might be postulated for the intended site of the plant. In the design of the European Pressurized Water Reactor (EPR) particular attention was paid to external hazards such as earthquake, airplane crash, and explosion pressure wave. The standard EPR covers a large range of possible site conditions, the design earthquake enveloping safe shutdown earthquakes (SSE) to be expected for potential sites. The loads for the design basis airplane crash and - if required - for the design extension airplane crash as well as for external Explosion Pressure Wave are defined depending on site specific requirements. Protection against other external load cases such as extreme winds and external flooding is also included in the standard design

  19. Hydropower externalities: a meta analysis

    NARCIS (Netherlands)

    Mattmann, M.; Logar, I.; Brouwer, R.

    2016-01-01

    This paper presents a meta-analysis of existing research related to the economic valuation of the external effects of hydropower. A database consisting of 81 observations derived from 29 studies valuing the non-market impacts of hydropower electricity generation is constructed with the main aim to

  20. Neuraxial blockade for external cephalic version: Cost analysis.

    Science.gov (United States)

    Yamasato, Kelly; Kaneshiro, Bliss; Salcedo, Jennifer

    2015-07-01

    Neuraxial blockade (epidural or spinal anesthesia/analgesia) with external cephalic version increases the external cephalic version success rate. Hospitals and insurers may affect access to neuraxial blockade for external cephalic version, but the costs to these institutions remain largely unstudied. The objective of this study was to perform a cost analysis of neuraxial blockade use during external cephalic version from hospital and insurance payer perspectives. Secondarily, we estimated the effect of neuraxial blockade on cesarean delivery rates. A decision-analysis model was developed using costs and probabilities occurring prenatally through the delivery hospital admission. Model inputs were derived from the literature, national databases, and local supply costs. Univariate and bivariate sensitivity analyses and Monte Carlo simulations were performed to assess model robustness. Neuraxial blockade was cost saving to both hospitals ($30 per delivery) and insurers ($539 per delivery) using baseline estimates. From both perspectives, however, the model was sensitive to multiple variables. Monte Carlo simulation indicated neuraxial blockade to be more costly in approximately 50% of scenarios. The model demonstrated that routine use of neuraxial blockade during external cephalic version, compared to no neuraxial blockade, prevented 17 cesarean deliveries for every 100 external cephalic versions attempted. Neuraxial blockade is associated with minimal hospital and insurer cost changes in the setting of external cephalic version, while reducing the cesarean delivery rate. © 2015 The Authors. Journal of Obstetrics and Gynaecology Research © 2015 Japan Society of Obstetrics and Gynecology.

  1. Procedural and submittal guidance for the individual plant examination of external events (IPEEE) for severe accident vulnerabilities

    International Nuclear Information System (INIS)

    Chen, J.T.; Chokshi, N.C.; Kenneally, R.M.; Kelly, G.B.; Beckner, W.D.; McCracken, C.; Murphy, A.J.; Reiter, L.; Jeng, D.

    1991-06-01

    Based on a Policy statement on Severe Accidents, the licensee of each nuclear power plant is requested to perform an individual plant examination. The plant examination systematically looks for vulnerabilities to severe accidents and cost-effective safety improvements that reduce or eliminate the important vulnerabilities. This document presents guidance for performing and reporting the results of the individual plant examination of external events (IPEEE). The guidance for reporting the results of the individual plant examination of internal events (IPE) is presented in NUREG-1335. 53 refs., 1 figs., 2 tabs

  2. Safety assessment of multi-unit NPP sites subject to external events

    International Nuclear Information System (INIS)

    Samaddar, Sujit; Hibino, Kenta; Coman, Ovidiu

    2014-01-01

    This paper presents a framework for conducting a probabilistic safety assessment of multi-unit sites against external events. The treatment of multiple hazard on a unit, interaction between units, implementation of severe accident measures, human reliability, environmental conditions, metric of risk for both reactor and non-reactor sources, integration of risk and responses and many such important factors need to be addressed within the context of this framework. The framework facilitates the establishment of a comprehensive methodology that can be applied internationally to the peer review of safety assessment of multi-unit sites under the impact of multiple external hazards. In summary, it can be said that the site safety assessment for a multi-unit site will be quite complex and need to start with individual unit risk assessments, these need to be combined considering the interactions between units and their responses, and the fragilities of the installations established considering the combined demands from all interactions. Using newly established risk metric the risk can then be integrated for the overall site. Fig. 2 shows schematically such a proposal. Much work has to done and the IAEA has established a working group that is systematically establishing the structure and process to incorporate the many issues that are a part of a multi-unit site safety assessment. (authors)

  3. Lessons learned from external hazards

    Energy Technology Data Exchange (ETDEWEB)

    Peinador, Miguel; Zerger, Benoit [European Commisison Joint Research Centre, Petten (Netherlands). Inst. for Energy and Transport; Ramos, Manuel Martin [European Commission Joint Research Centre, Brussels (Belgium). Nuclear Safety and Security Coordination; Wattrelos, Didier [Institut de Radioprotection et de Surete Nucleaire (IRSN), Fontenay-aux-Roses (France); Maqua, Michael [Gesellschaft fuer Anlagen- und Reaktorsicherheit (GRS) mbH, Koeln (Germany)

    2014-01-15

    This paper presents a study performed by the European Clearinghouse of the Joint Research Centre on Operational Experience for nuclear power plants in cooperation with IRSN and GRS covering events reported by nuclear power plants in relation to external hazards. It summarizes the review of 235 event reports from 3 different databases. The events were grouped in 9 categories according to the nature of the external hazard involved, and the specific lessons learned and recommendations that can be derived from each of these categories are presented. Additional 'cross-cutting' recommendations covering several or all the external hazards considered are also discussed. These recommendations can be useful in preventing this type of events from happening again or in limiting their consequences. The study was launched in 2010 and therefore it does not cover the Fukushima event. This paper presents the main findings and recommendations raised by this study. (orig.)

  4. External PIXE analysis of old inks and papers

    International Nuclear Information System (INIS)

    Hassanzadeh, A.; Lamehi-Rachti, M.; Oliaiy, P.; Rahighi, J.; Shokouhi, F.

    1999-01-01

    Proton Induced X-ray Emission, PIXE is a very well established analytical method. This technique of analysis can equally be applied both in vacuum, internal PIXE, and in atmosphere, external PIXE. External PIXE has been applied to material analysis in Van de Graaff laboratory at AEOI using filters and funny filters. Advantages of using these filters have been studied when analysing ancient written documents such as envelopes, inks, and newspapers. This technique clearly demonstrated the differences between new and old inks and papers. More data is needed to show other features of this technique. (author)

  5. 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

  6. Relations of Parenting and Temperament to Chinese Children's Experience of Negative Life Events, Coping Efficacy, and Externalizing Problems

    Science.gov (United States)

    Zhou, Qing; Wang, Yun; Deng, Xianli; Eisenberg, Nancy; Wolchik, Sharlene A.; Tein, Jenn-Yun

    2008-01-01

    The relations of parenting and temperament (effortful control and anger/frustration) to children's externalizing problems were examined in a 3.8-year longitudinal study of 425 native Chinese children (6-9 years) from Beijing. Children's experience of negative life events and coping efficacy were examined as mediators in the parenting- and…

  7. Using variable transformations to perform common event analysis

    International Nuclear Information System (INIS)

    Worrell, R.B.

    1977-01-01

    Any analytical method for studying the effect of common events on the behavior of a system is considered as being a form of common event analysis. The particular common events that are involved often represent quite different phenomena, and this has led to the development of different kinds of common event analysis. For example, common mode failure analysis, common cause analysis, critical location analysis, etc., are all different kinds of common event analysis for which the common events involved represent different phenomena. However, the problem that must be solved for each of these different kinds of common event analysis is essentially the same: Determine the effect of common events on the behavior of a system. Thus, a technique that is useful in achieving one kind of common event analysis is often useful in achieving other kinds of common event analysis

  8. Analysis of syntactic and semantic features for fine-grained event-spatial understanding in outbreak news reports

    Directory of Open Access Journals (Sweden)

    Chanlekha Hutchatai

    2010-03-01

    Full Text Available Abstract Background Previous studies have suggested that epidemiological reasoning needs a fine-grained modelling of events, especially their spatial and temporal attributes. While the temporal analysis of events has been intensively studied, far less attention has been paid to their spatial analysis. This article aims at filling the gap concerning automatic event-spatial attribute analysis in order to support health surveillance and epidemiological reasoning. Results In this work, we propose a methodology that provides a detailed analysis on each event reported in news articles to recover the most specific locations where it occurs. Various features for recognizing spatial attributes of the events were studied and incorporated into the models which were trained by several machine learning techniques. The best performance for spatial attribute recognition is very promising; 85.9% F-score (86.75% precision/85.1% recall. Conclusions We extended our work on event-spatial attribute recognition by focusing on machine learning techniques, which are CRF, SVM, and Decision tree. Our approach avoided the costly development of an external knowledge base by employing the feature sources that can be acquired locally from the analyzed document. The results showed that the CRF model performed the best. Our study indicated that the nearest location and previous event location are the most important features for the CRF and SVM model, while the location extracted from the verb's subject is the most important to the Decision tree model.

  9. Progress for the Industry Application External Hazard Analyses Early Demonstration

    Energy Technology Data Exchange (ETDEWEB)

    Smith, Curtis L. [Idaho National Lab. (INL), Idaho Falls, ID (United States); Prescott, Steven [Idaho National Lab. (INL), Idaho Falls, ID (United States); Coleman, Justin [Idaho National Lab. (INL), Idaho Falls, ID (United States); Ryan, Emerald [Idaho State Univ., Pocatello, ID (United States); Bhandari, Bishwo [Idaho State Univ., Pocatello, ID (United States); Sludern, Daniel [Idaho State Univ., Pocatello, ID (United States); Pope, Chad [Idaho State Univ., Pocatello, ID (United States); Sampath, Ram [Centroid PIC, Idaho Falls, ID (United States)

    2015-09-01

    This report describes the current progress and status related to the Industry Application #2 focusing on External Hazards. For this industry application within the Light Water Reactor Sustainability (LWRS) Program Risk-Informed Safety Margin Characterization (RISMC) R&D Pathway, we will create the Risk-Informed Margin Management (RIMM) approach to represent meaningful (i.e., realistic facility representation) event scenarios and consequences by using an advanced 3D facility representation that will evaluate external hazards such as flooding and earthquakes in order to identify, model and analyze the appropriate physics that needs to be included to determine plant vulnerabilities related to external events; manage the communication and interactions between different physics modeling and analysis technologies; and develop the computational infrastructure through tools related to plant representation, scenario depiction, and physics prediction. One of the unique aspects of the RISMC approach is how it couples probabilistic approaches (the scenario) with mechanistic phenomena representation (the physics) through simulation. This simulation-based modeling allows decision makers to focus on a variety of safety, performance, or economic metrics. In this report, we describe the evaluation of various physics toolkits related to flooding representation. Ultimately, we will be coupling the flooding representation with other events such as earthquakes in order to provide coupled physics analysis for scenarios where interactions exist.

  10. 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.

  11. Internal versus external preference analysis : an exploratory study on end-user evaluation

    NARCIS (Netherlands)

    Kleef, van E.; Trijp, van H.C.M.; Luning, P.A.

    2006-01-01

    Internal and external preference analysis emphasise fundamentally different perspectives on the same data. We extend the literature on comparisons between internal and external preference analysis by incorporating the perspective of the end user of the preference analysis results. From a conceptual

  12. ExternE: Externalities of energy Vol. 2. Methodology

    International Nuclear Information System (INIS)

    Berry, J.; Holland, M.; Watkiss, P.

    1995-01-01

    This report describes the methodology used by the ExternE Project of the European Commission (DGXII) JOULE Programme for assessment of the external costs of energy. It is one of a series of reports describing analysis of nuclear, fossil and renewable fuel cycles for assessment of the externalities associated with electricity generation. Part I of the report deals with analysis of impacts, and Part II with the economic valuation of those impacts. Analysis is conducted on a marginal basis, to allow the effect of an incremental investment in a given technology to be quantified. Attention has been paid to the specificity of results with respect to the location of fuel cycle activities, the precise technologies used, and the type and source of fuel. The main advantages of this detailed approach are as follows: It takes full and proper account of the variability of impacts that might result from different power projects; It is more transparent than analysis based on hypothetically 'representative' cases for each of the different fuel cycles; It provides a framework for consistent comparison between fuel cycles. A wide variety of impacts have been considered. These include the effects of air pollution on the natural and human environment, consequences of accidents in the workplace, impacts of noise and visual intrusion on amenity, and the effects of climate change arising from the release of greenhouse gases. Wherever possible we have used the 'impact pathway' or 'damage function' approach to follow the analysis from identification of burdens (e.g. emissions) through to impact assessment and then valuation in monetary terms. This has required a detailed knowledge of the technologies involved, pollutant dispersion, analysis of effects on human and environmental health, and economics. In view of this the project brought together a multi-disciplinary team with experts from many European countries and the USA. The spatial and temporal ranges considered in the analysis are

  13. 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

  14. Bayesian analysis of rare events

    Energy Technology Data Exchange (ETDEWEB)

    Straub, Daniel, E-mail: straub@tum.de; Papaioannou, Iason; Betz, Wolfgang

    2016-06-01

    In many areas of engineering and science there is an interest in predicting the probability of rare events, in particular in applications related to safety and security. Increasingly, such predictions are made through computer models of physical systems in an uncertainty quantification framework. Additionally, with advances in IT, monitoring and sensor technology, an increasing amount of data on the performance of the systems is collected. This data can be used to reduce uncertainty, improve the probability estimates and consequently enhance the management of rare events and associated risks. Bayesian analysis is the ideal method to include the data into the probabilistic model. It ensures a consistent probabilistic treatment of uncertainty, which is central in the prediction of rare events, where extrapolation from the domain of observation is common. We present a framework for performing Bayesian updating of rare event probabilities, termed BUS. It is based on a reinterpretation of the classical rejection-sampling approach to Bayesian analysis, which enables the use of established methods for estimating probabilities of rare events. By drawing upon these methods, the framework makes use of their computational efficiency. These methods include the First-Order Reliability Method (FORM), tailored importance sampling (IS) methods and Subset Simulation (SuS). In this contribution, we briefly review these methods in the context of the BUS framework and investigate their applicability to Bayesian analysis of rare events in different settings. We find that, for some applications, FORM can be highly efficient and is surprisingly accurate, enabling Bayesian analysis of rare events with just a few model evaluations. In a general setting, BUS implemented through IS and SuS is more robust and flexible.

  15. AN ANALYSIS OF RISK EVENTS IN THE OIL-TANKER MAINTENANCE BUSINESS

    Directory of Open Access Journals (Sweden)

    Roque Rabechini Junior

    2012-12-01

    Full Text Available This work presents the results of an investigation into risk events and their respective causes, carried out in ship maintenance undertakings in the logistical sector of the Brazilian oil industry. Its theoretical, conceptual positioning lies in those aspects related to risk management of the undertakings as instruments of support in decision making by executives in the tanker-maintenance business. The case-study method was used as an alternative methodology with a qualitative approach of an exploratory nature and, for the presentation of data, a descriptive format was chosen. Through the analysis of 75 risk events in projects of tanker docking it was possible to extract eight of the greatest relevance. The risk analysis facilitated the identification of actions aimed at their mitigation. As a conclusion it was possible to propose a risk-framework model in four categories, HSE (health, safety and the environment, technicians, externalities and management, designed to provide tanker-docking business executives and administrators, with evidence of actions to assist in their decision-making processes. Finally, the authors identified proposals for further study as well as showing the principal limitations of the study.

  16. Human reliability analysis using event trees

    International Nuclear Information System (INIS)

    Heslinga, G.

    1983-01-01

    The shut-down procedure of a technologically complex installation as a nuclear power plant consists of a lot of human actions, some of which have to be performed several times. The procedure is regarded as a chain of modules of specific actions, some of which are analyzed separately. The analysis is carried out by making a Human Reliability Analysis event tree (HRA event tree) of each action, breaking down each action into small elementary steps. The application of event trees in human reliability analysis implies more difficulties than in the case of technical systems where event trees were mainly used until now. The most important reason is that the operator is able to recover a wrong performance; memory influences play a significant role. In this study these difficulties are dealt with theoretically. The following conclusions can be drawn: (1) in principle event trees may be used in human reliability analysis; (2) although in practice the operator will recover his fault partly, theoretically this can be described as starting the whole event tree again; (3) compact formulas have been derived, by which the probability of reaching a specific failure consequence on passing through the HRA event tree after several times of recovery is to be calculated. (orig.)

  17. Analysis of External Treatment Methods and Technical Characteristics of External Treatment

    Science.gov (United States)

    Zhang, Rui; Miao, Mingsan; Bai, Ming

    2018-01-01

    Chinese medicine external therapy is a treatment method of Chinese medicine with Chinese characteristics. The effect of traditional Chinese medicine external treatment, convenient operation, external treatment and technology has great prospects for development. The traditional Chinese medicine external treatment method and technical characteristics were analyzed.

  18. External-beam PIXE analysis of small sculptures

    International Nuclear Information System (INIS)

    Gyodi, I.; Demeter, I.; Hollos-Nagy, K.; Kovacs, I.; Szokefalvi-Nagy, Z.

    1999-01-01

    Non-destructive analysis of precious art objects is an important tool to solve provenance problems or to facilitate restoration. External beam PIXE analysis is one of the most powerful and popular methods used in this respect. The paper summarises the external beam PIXE set-up at the Accelerator Laboratory in Budapest, and two selected applications are described. Different parts of a small Cambodian metal sculpture probably made in the 11th century were analysed. It was observed that the sculpture was composed of an iron core and an outer bronze shell. This sculptural technique was well known in the Middle-East but no indication has been found about its use in the Far-East, yet. Before its restoration paint traces on a wooden relief of St. Jerome made by an unknown artist in about 1600 were analysed. Different white and red paints were distinguished at selected points and the presence of titanium on a certain part of the relief was attributed to a repainting in modern times

  19. Effectiveness Analysis of a Non-Destructive Single Event Burnout Test Methodology

    CERN Document Server

    Oser, P; Spiezia, G; Fadakis, E; Foucard, G; Peronnard, P; Masi, A; Gaillard, R

    2014-01-01

    It is essential to characterize power MosFETs regarding their tolerance to destructive Single Event Burnouts (SEB). Therefore, several non-destructive test methods have been developed to evaluate the SEB cross-section of power devices. A power MosFET has been evaluated using a test circuit, designed according to standard non-destructive test methods discussed in the literature. Guidelines suggest a prior adaptation of auxiliary components to the device sensitivity before the radiation test. With the first value chosen for the de-coupling capacitor, the external component initiated destructive events and affected the evaluation of the cross-section. As a result, the influence of auxiliary components on the device cross-section was studied. This paper presents the obtained experimental results, supported by SPICE simulations, to evaluate and discuss how the circuit effectiveness depends on the external components.

  20. Collecting operational event data for statistical analysis

    International Nuclear Information System (INIS)

    Atwood, C.L.

    1994-09-01

    This report gives guidance for collecting operational data to be used for statistical analysis, especially analysis of event counts. It discusses how to define the purpose of the study, the unit (system, component, etc.) to be studied, events to be counted, and demand or exposure time. Examples are given of classification systems for events in the data sources. A checklist summarizes the essential steps in data collection for statistical analysis

  1. EVENT PLANNING USING FUNCTION ANALYSIS

    Energy Technology Data Exchange (ETDEWEB)

    Lori Braase; Jodi Grgich

    2011-06-01

    Event planning is expensive and resource intensive. Function analysis provides a solid foundation for comprehensive event planning (e.g., workshops, conferences, symposiums, or meetings). It has been used at Idaho National Laboratory (INL) to successfully plan events and capture lessons learned, and played a significant role in the development and implementation of the “INL Guide for Hosting an Event.” Using a guide and a functional approach to planning utilizes resources more efficiently and reduces errors that could be distracting or detrimental to an event. This integrated approach to logistics and program planning – with the primary focus on the participant – gives us the edge.

  2. Discrete event simulation model for external yard choice of import container terminal in a port buffer area

    Science.gov (United States)

    Rusgiyarto, Ferry; Sjafruddin, Ade; Frazila, Russ Bona; Suprayogi

    2017-06-01

    Increasing container traffic and land acquisition problem for terminal expansion leads to usage of external yard in a port buffer area. This condition influenced the terminal performance because a road which connects the terminal and the external yard was also used by non-container traffic. Location choice problem considered to solve this condition, but the previous research has not taken account a stochastic condition of container arrival rate and service time yet. Bi-level programming framework was used to find optimum location configuration. In the lower-level, there was a problem to construct the equation, which correlated the terminal operation and the road due to different time cycle equilibrium. Container moves from the quay to a terminal gate in a daily unit of time, meanwhile, it moves from the terminal gate to the external yard through the road in a minute unit of time. If the equation formulated in hourly unit equilibrium, it cannot catch up the container movement characteristics in the terminal. Meanwhile, if the equation formulated in daily unit equilibrium, it cannot catch up the road traffic movement characteristics in the road. This problem can be addressed using simulation model. Discrete Event Simulation Model was used to simulate import container flow processes in the container terminal and external yard. Optimum location configuration in the upper-level was the combinatorial problem, which was solved by Full Enumeration approach. The objective function of the external yard location model was to minimize user transport cost (or time) and to maximize operator benefit. Numerical experiment was run for the scenario assumption of two container handling ways, three external yards, and thirty-day simulation periods. Jakarta International Container Terminal (JICT) container characteristics data was referred for the simulation. Based on five runs which were 5, 10, 15, 20, and 30 repetitions, operation one of three available external yards (external yard

  3. Analysis of internal events for the Unit 1 of the Laguna Verde nuclear power station; Analisis de eventos internos para la Unidad 1 de la Central Nucleolelectrica de Laguna Verde

    Energy Technology Data Exchange (ETDEWEB)

    Huerta B, A.; Aguilar T, O.; Nunez C, A.; Lopez M, R. [Comision Nacional de Seguridad Nuclear y Salvaguardias, 03000 Mexico D.F. (Mexico)

    1993-07-01

    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)

  4. Life-cycle analysis and external costs in transportation

    International Nuclear Information System (INIS)

    Delucchi, M.A.

    2002-01-01

    The assessment of greenhouse gas impacts in the US shows that against a baseline gasoline vehicle, the impact of including the full fuel cycle generally reduces the relative advantages of alternative transportation fuels. While a switch to diesel is estimated to save 30% as compared to gasoline, the savings from natural gas/LPG are (around 20%), for ethanol from corn (8%) and for battery electricity vehicles using power from coal (6%) are much smaller. This is largely due to the use of LCA rather than end-use comparisons. However, the results also show that there would be large savings from the use of ethanol from fuel cells using methanol (39%) or natural gas (50%), while ethanol from wood in a conventional engine appears to have the greatest savings (63%). In external costs of motor vehicle use, analysis results were presented for both air pollution and energy security impacts (including SPR, military expenditures, macro-economic costs and pecuniary costs) as well as water pollution, noise and congestion impacts. The results suggest that externalities amount to 1.2 US cents per mile travelled in gasoline powered vehicle. The most significant externality is related to air pollution. Costs associated with US defence, the SPR, and climate change are quite insignificant. The only other variable of significance is the impact on the economy, through the transfer of wealth outside the US (referred to as 'pecuniary externality') and the oil price shock impacts on the economy. A comparison of external costs and subsidies for different transportation modes in the US (gas or electric cars, transit bus, light rail, heavy rail) showed that subsidies available to public transit system greatly outweigh the benefit in reduced externalities avoided. In the comparison of social costs of transportation alternatives, differences in external cost, while not trivial, are outweighed by the differences in direct costs or in subsidies. (author)

  5. Preliminary safety analysis of unscrammed events for KLFR

    International Nuclear Information System (INIS)

    Kim, S.J.; Ha, G.S.

    2005-01-01

    The report presents the design features of KLFR; Safety Analysis Code; steady-state calculation results and analysis results of unscrammed events. The calculations of the steady-state and unscrammed events have been performed for the conceptual design of KLFR using SSC-K code. UTOP event results in no fuel damage and no centre-line melting. The inherent safety features are demonstrated through the analysis of ULOHS event. Although the analysis of ULOF has much uncertainties in the pump design, the analysis results show the inherent safety characteristics. 6% flow of rated flow of natural circulation is formed in the case of ULOF. In the metallic fuel rod, the cladding temperature is somewhat high due to the low heat transfer coefficient of lead. ULOHS event should be considered in design of RVACS for long-term cooling

  6. 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

  7. The Psychological Assessment in Operational Events

    International Nuclear Information System (INIS)

    Abramova, V.N.; Volkov, E.V.

    1998-01-01

    The possibilities of Psychological Assessment in Operational Events in nuclear power engineering are discussed. The approach of psychology use in quantitative analysis of direct and root causes of operational events is presented. The main attention is paid to the practical method of investigation of an individual who makes an error. The socio-technical system elements can be considered by this method as the external conditions, affecting correctness or errors of actions. The types of errors (violation, mistake, slips) can be clarified. The direct causes of failures and sources of probable root causes of errors also can be defined. Experience shows that the psychological situation of events caused by a human error depends on professional competence, motivation and some professionally important psychological qualities of a person, his functional state, psycho-physiological qualities, characteristics of mentality, attention and memory. In an emergency situation successful personnel performance is mainly effected by such professional qualities as the ability to take the lead in actions, to resolve urgent problems of minimizing the scale of the accident significance; personal participation in dangerous procedures of the accident follow-up, even risking one's life; devotion to one's job; resolute and bold actions; high level of self-control; thoroughness and conscientiousness. External means of activity, influencing the events, include ergonomic characteristics of working place, ergonomics of events technology. External means can be also defined by socio-psychological situation in a group, which refers to the data of social conditions, social-political situation, relationships between people, and by organizational factors. (authors)

  8. Externalities of energy. Swedish implementation of the ExternE methodology

    International Nuclear Information System (INIS)

    Nilsson, Maans; Gullberg, M.

    1998-01-01

    The growing interest for developing economic instruments for efficient environmental policies has opened up a large area of multi-disciplinary research. ExternE is an example of this research, combining disciplines such as engineering, ecology, immunology and economics expertise to create new knowledge about how environmental pressures from energy production affect our nature and society. The ExternE Project aims to identify and, as far as possible quantify the externalities of energy production in Europe. The Stockholm Environment Institute has carried out a preliminary aggregation: -Coal Fuel Cycle: centred around Vaesteraas Kraftvaermeverk, Vaesteraas. This is the largest co-generation plant in Sweden, with four blocks and a maximum co-generation output of 520 MW electricity and 950 MW heat. The analysis is carried out on boiler B4. -Biomass Fuel Cycle: centred around Haendeloeverket, Norrkoeping. This plant predominately burns forestry residues, but a variety of fuels are combusted. Haendeloeverket has an installed capacity of 100 MW electricity and 375 MW heat, in a total of three boilers and two back-pressure turbines. The analysis is carried out on boiler P13. -Hydro Fuel Cycle: Klippens Kraftstation, Storuman. Built in 1990-1994, it is the youngest hydro power station in Sweden. It has been designed and built with significant efforts to account for and protect environmental values. Installed capacity is 28 MW. The environmental impact assessment from the construction of this plant is carried out, but the evaluation is still not finalized. The preliminary aggregation aimed to test whether ExternE results could be used to make estimates for the entire Swedish electricity production system. Hence, national results as well as results from other partner countries in ExternE has been applied

  9. 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

  10. Methodology for the analysis of external flooding in CN Asco-II and CN Vandellos during the performance of stress tests

    International Nuclear Information System (INIS)

    Aleman, A.; Cobas, I.; Sabater, J.; Canadell, F.; Garces, L.; Otero, M.

    2012-01-01

    The work carried out in relation to extemal floods have allowed synthesized in a unique methodology to obtain the entire process of margins against external flooding, including identification of the extemal external events could cause flooding.

  11. Research on Visual Analysis Methods of Terrorism Events

    Science.gov (United States)

    Guo, Wenyue; Liu, Haiyan; Yu, Anzhu; Li, Jing

    2016-06-01

    Under the situation that terrorism events occur more and more frequency throughout the world, improving the response capability of social security incidents has become an important aspect to test governments govern ability. Visual analysis has become an important method of event analysing for its advantage of intuitive and effective. To analyse events' spatio-temporal distribution characteristics, correlations among event items and the development trend, terrorism event's spatio-temporal characteristics are discussed. Suitable event data table structure based on "5W" theory is designed. Then, six types of visual analysis are purposed, and how to use thematic map and statistical charts to realize visual analysis on terrorism events is studied. Finally, experiments have been carried out by using the data provided by Global Terrorism Database, and the results of experiments proves the availability of the methods.

  12. Davidson's Externalism and Swampman's Troublesome Biography

    Directory of Open Access Journals (Sweden)

    André Leclerc

    2005-12-01

    Full Text Available After the seminal works of Putnam (1975, Burge (1979, and Kripke (1982, the next important contribution to externalism is certainly Davidson’s (mainly 1987, 1988, 1989, 2001. By criticizing the posi-tions of these philosophers, Davidson elaborated his own brand of exter-nalism. We shall first present some features of Davidson’s externalism (the importance of historical-causal connections for the foundation of language and thought, for the explanation of how language can be learned, and how attitudes can be identified by the interpreter, and fi-nally how mental content is determined by appealing to the idea of trian-gulation, to prepare the discussion of a few problems. We then discuss two questions in Davidson’s externalism. First, how to reconcile the fact that external factors determine mental content, as Putnam, Burge and Davidson himself argued convincingly, with token-physicalism, the thesis that mental events are identical with physical events occurring “in the head” (or the thesis that mental events supervenes locally on brain ac-tivities? The second main problem is how to reconcile the first person authority with some prima facie consequences of externalism, mainly that we should know the relevant parts of our (natural and social envi-ronment in order to know the content of our own thoughts? We argue that Davidson’s answer to the first question is not successful, while his answer to the second was a breakthrough.

  13. Externalizing psychopathology and gain-loss feedback in a simulated gambling task: dissociable components of brain response revealed by time-frequency analysis.

    Science.gov (United States)

    Bernat, Edward M; Nelson, Lindsay D; Steele, Vaughn R; Gehring, William J; Patrick, Christopher J

    2011-05-01

    Externalizing is a broad construct that reflects propensity toward a variety of impulse control problems, including antisocial personality disorder and substance use disorders. Two event-related potential responses known to be reduced among individuals high in externalizing proneness are the P300, which reflects postperceptual processing of a stimulus, and the error-related negativity (ERN), which indexes performance monitoring based on endogenous representations. In the current study, the authors used a simulated gambling task to examine the relation between externalizing proneness and the feedback-related negativity (FRN), a brain response that indexes performance monitoring related to exogenous cues, which is thought to be highly related to the ERN. Time-frequency (TF) analysis was used to disentangle the FRN from the accompanying P300 response to feedback cues by parsing the overall feedback-locked potential into distinctive theta (4-7 Hz) and delta (<3 Hz) TF components. Whereas delta-P300 amplitude was reduced among individuals high in externalizing proneness, theta-FRN response was unrelated to externalizing. These findings suggest that in contrast with previously reported deficits in endogenously based performance monitoring (as indexed by the ERN), individuals prone to externalizing problems show intact monitoring of exogenous cues (as indexed by the FRN). The results also contribute to a growing body of evidence indicating that the P300 is attenuated across a broad range of task conditions in high-externalizing individuals.

  14. Elemental analysis with external-beam PIXE

    Science.gov (United States)

    Lin, E. K.; Wang, C. W.; Teng, P. K.; Huang, Y. M.; Chen, C. Y.

    1992-05-01

    A beamline system and experimental setup has been established for elemental analysis using PIXE with an external beam. Experiments for the study of the elemental composition of ancient Chinese potsherds (the Min and Ching ages) were performed. Continuum X-ray spectra from the samples bombarded by 3 MeV protons have been measured with a Si(Li) detector. From the analysis of PIXE data, the concentration of the main elements (Al, Si, K, and Ca) and of more than ten trace elements in the matrices and glazed surfaces were determined. Results for two different potsherds are presented, and those obtained from the glaze colorants are compared with the results of measurements on a Ching blue-and-white porcelain vase.

  15. Procedure proposed for performance of a probabilistic safety analysis for the event of ''Air plane crash''

    International Nuclear Information System (INIS)

    Hoffmann, H.H.

    1998-01-01

    A procedures guide for a probabilistic safety analysis for the external event 'Air plane crash' has been prepared. The method is based on analysis done within the framework of PSA for German NPPs as well as on international documents. Both crashes of military air planes and commercial air planes contribute to the plant risk. For the determination of the plant related crash rate the air traffic will be divided into 3 different categories of air traffic: - The landing and takeoff phase, - the airlane traffic and waiting loop traffic, - the free air traffic, and the air planes into different types and weight classes. (orig./GL) [de

  16. External cooling: The SWR 1000 severe accident management strategy. Part 1: motivation, strategy, analysis: melt phase, vessel integrity during melt-water interaction

    International Nuclear Information System (INIS)

    Kolev, Nikolay Ivanov

    2004-01-01

    This paper provides the description of the basics behind design features for the severe accident management strategy of the SWR 1000. The hydrogen detonation/deflagration problem is avoided by containment inertization. In-vessel retention of molten core debris via water cooling of the external surface of the reactor vessel is the severe accident management concept of the SWR 1000 passive plant. During postulated bounding severe accidents, the accident management strategy is to flood the reactor cavity with Core Flooding Pool water and to submerge the reactor vessel, thus preventing vessel failure in the SWR 1000. Considerable safety margins have determined by using state of the art experiment and analysis: regarding (a) strength of the vessel during the melt relocation and its interaction with water; (b) the heat flux at the external vessel wall; (c) the structural resistance of the hot structures during the long term period. Ex-vessel events are prevented by preserving the integrity of the vessel and its penetrations and by assuring positive external pressure at the predominant part of the external vessel in the region of the molten corium pool. Part 1 describes the motivation for selecting this strategy, the general description of the strategy and the part of the analysis associated with the vessel integrity during the melt-water interaction. (author)

  17. Negated bio-events: analysis and identification

    Science.gov (United States)

    2013-01-01

    Background Negation occurs frequently in scientific literature, especially in biomedical literature. It has previously been reported that around 13% of sentences found in biomedical research articles contain negation. Historically, the main motivation for identifying negated events has been to ensure their exclusion from lists of extracted interactions. However, recently, there has been a growing interest in negative results, which has resulted in negation detection being identified as a key challenge in biomedical relation extraction. In this article, we focus on the problem of identifying negated bio-events, given gold standard event annotations. Results We have conducted a detailed analysis of three open access bio-event corpora containing negation information (i.e., GENIA Event, BioInfer and BioNLP’09 ST), and have identified the main types of negated bio-events. We have analysed the key aspects of a machine learning solution to the problem of detecting negated events, including selection of negation cues, feature engineering and the choice of learning algorithm. Combining the best solutions for each aspect of the problem, we propose a novel framework for the identification of negated bio-events. We have evaluated our system on each of the three open access corpora mentioned above. The performance of the system significantly surpasses the best results previously reported on the BioNLP’09 ST corpus, and achieves even better results on the GENIA Event and BioInfer corpora, both of which contain more varied and complex events. Conclusions Recently, in the field of biomedical text mining, the development and enhancement of event-based systems has received significant interest. The ability to identify negated events is a key performance element for these systems. We have conducted the first detailed study on the analysis and identification of negated bio-events. Our proposed framework can be integrated with state-of-the-art event extraction systems. The

  18. Analysis of extreme events

    CSIR Research Space (South Africa)

    Khuluse, S

    2009-04-01

    Full Text Available ) determination of the distribution of the damage and (iii) preparation of products that enable prediction of future risk events. The methodology provided by extreme value theory can also be a powerful tool in risk analysis...

  19. LOSP-initiated event tree analysis for BWR

    International Nuclear Information System (INIS)

    Watanabe, Norio; Kondo, Masaaki; Uno, Kiyotaka; Chigusa, Takeshi; Harami, Taikan

    1989-03-01

    As a preliminary study of 'Japanese Model Plant PSA', a LOSP (loss of off-site power)-initiated Event Tree Analysis for a Japanese typical BWR was carried out solely based on the open documents such as 'Safety Analysis Report'. The objectives of this analysis are as follows; - to delineate core-melt accident sequences initiated by LOSP, - to evaluate the importance of core-melt accident sequences in terms of occurrence frequency, and - to develop a foundation of plant information and analytical procedures for efficiently performing further 'Japanese Model Plant PSA'. This report describes the procedure and results of the LOSP-initiated Event Tree Analysis. In this analysis, two types of event trees, Functional Event Tree and Systemic Event Tree, were developed to delineate core-melt accident sequences and to quantify their frequencies. Front-line System Event Tree was prepared as well to provide core-melt sequence delineation for accident progression analysis of Level 2 PSA which will be followed in a future. Applying U.S. operational experience data such as component failure rates and a LOSP frequency, we obtained the following results; - The total frequency of core-melt accident sequences initiated by LOSP is estimated at 5 x 10 -4 per reactor-year. - The dominant sequences are 'Loss of Decay Heat Removal' and 'Loss of Emergency Electric Power Supply', which account for more than 90% of the total core-melt frequency. In this analysis, a higher value of 0.13/R·Y was used for the LOSP frequency than experiences in Japan and any recovery action was not considered. In fact, however, there has been no experience of LOSP event in Japanese nuclear power plants so far and it is also expected that offsite power and/or PCS would be recovered before core melt. Considering Japanese operating experience and recovery factors will reduce the total core-melt frequency to less than 10 -6 per reactor-year. (J.P.N.)

  20. CATEGORIZATION OF EVENT SEQUENCES FOR LICENSE APPLICATION

    Energy Technology Data Exchange (ETDEWEB)

    G.E. Ragan; P. Mecheret; D. Dexheimer

    2005-04-14

    The purposes of this analysis are: (1) Categorize (as Category 1, Category 2, or Beyond Category 2) internal event sequences that may occur before permanent closure of the repository at Yucca Mountain. (2) Categorize external event sequences that may occur before permanent closure of the repository at Yucca Mountain. This includes examining DBGM-1 seismic classifications and upgrading to DBGM-2, if appropriate, to ensure Beyond Category 2 categorization. (3) State the design and operational requirements that are invoked to make the categorization assignments valid. (4) Indicate the amount of material put at risk by Category 1 and Category 2 event sequences. (5) Estimate frequencies of Category 1 event sequences at the maximum capacity and receipt rate of the repository. (6) Distinguish occurrences associated with normal operations from event sequences. It is beyond the scope of the analysis to propose design requirements that may be required to control radiological exposure associated with normal operations. (7) Provide a convenient compilation of the results of the analysis in tabular form. The results of this analysis are used as inputs to the consequence analyses in an iterative design process that is depicted in Figure 1. Categorization of event sequences for permanent retrieval of waste from the repository is beyond the scope of this analysis. Cleanup activities that take place after an event sequence and other responses to abnormal events are also beyond the scope of the analysis.

  1. CATEGORIZATION OF EVENT SEQUENCES FOR LICENSE APPLICATION

    International Nuclear Information System (INIS)

    G.E. Ragan; P. Mecheret; D. Dexheimer

    2005-01-01

    The purposes of this analysis are: (1) Categorize (as Category 1, Category 2, or Beyond Category 2) internal event sequences that may occur before permanent closure of the repository at Yucca Mountain. (2) Categorize external event sequences that may occur before permanent closure of the repository at Yucca Mountain. This includes examining DBGM-1 seismic classifications and upgrading to DBGM-2, if appropriate, to ensure Beyond Category 2 categorization. (3) State the design and operational requirements that are invoked to make the categorization assignments valid. (4) Indicate the amount of material put at risk by Category 1 and Category 2 event sequences. (5) Estimate frequencies of Category 1 event sequences at the maximum capacity and receipt rate of the repository. (6) Distinguish occurrences associated with normal operations from event sequences. It is beyond the scope of the analysis to propose design requirements that may be required to control radiological exposure associated with normal operations. (7) Provide a convenient compilation of the results of the analysis in tabular form. The results of this analysis are used as inputs to the consequence analyses in an iterative design process that is depicted in Figure 1. Categorization of event sequences for permanent retrieval of waste from the repository is beyond the scope of this analysis. Cleanup activities that take place after an event sequence and other responses to abnormal events are also beyond the scope of the analysis

  2. Network externalities in telecommunication industry: An analysis of Serbian market

    Directory of Open Access Journals (Sweden)

    Trifunović Dejan

    2016-01-01

    Full Text Available This paper deals with network competition and provides empirical analysis of market concentration, network and call externalities, access pricing, price discrimination and switching costs in Serbian mobile phone telecommunications market. It is shown that network externalities governed the expansion of this market until 2008. Upon entry of VIP incumbents didn't engage in predatory behaviour towards entrant aiming to benefit from locked- in users. The policy of mobile phone number portability reduced on-net prices and substantially increased consumer's surplus. In contrast to some previous research, this policy was pro-competitive in Serbia. We have also determined that users of the network with the largest market share benefit the most from call externalities. Finally, one network does not price discriminate between outgoing and incoming roaming calls, which implies that users of this network have higher level pecuniary externalities in roaming compared to users of price discriminating networks.

  3. Analysis for Human-related Events during the Overhaul

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Ji Tae; Kim, Min Chull; Choi, Dong Won; Lee, Durk Hun [Korea Institute of Nuclear Safety, Daejeon (Korea, Republic of)

    2011-10-15

    The event frequency due to human error is decreasing among 20 operating Nuclear Power Plants (NPPs) excluding the NPP (Shin-Kori unit-1) in the commissioning stage since 2008. However, the events due to human error during an overhaul (O/H) occur annually (see Table I). An analysis for human-related events during the O/H was performed. Similar problems were identified for each event from the analysis and also, organizational and safety cultural factors were also identified

  4. TEMAC, Top Event Sensitivity Analysis

    International Nuclear Information System (INIS)

    Iman, R.L.; Shortencarier, M.J.

    1988-01-01

    1 - Description of program or function: TEMAC is designed to permit the user to easily estimate risk and to perform sensitivity and uncertainty analyses with a Boolean expression such as produced by the SETS computer program. SETS produces a mathematical representation of a fault tree used to model system unavailability. In the terminology of the TEMAC program, such a mathematical representation is referred to as a top event. The analysis of risk involves the estimation of the magnitude of risk, the sensitivity of risk estimates to base event probabilities and initiating event frequencies, and the quantification of the uncertainty in the risk estimates. 2 - Method of solution: Sensitivity and uncertainty analyses associated with top events involve mathematical operations on the corresponding Boolean expression for the top event, as well as repeated evaluations of the top event in a Monte Carlo fashion. TEMAC employs a general matrix approach which provides a convenient general form for Boolean expressions, is computationally efficient, and allows large problems to be analyzed. 3 - Restrictions on the complexity of the problem - Maxima of: 4000 cut sets, 500 events, 500 values in a Monte Carlo sample, 16 characters in an event name. These restrictions are implemented through the FORTRAN 77 PARAMATER statement

  5. A Key Event Path Analysis Approach for Integrated Systems

    Directory of Open Access Journals (Sweden)

    Jingjing Liao

    2012-01-01

    Full Text Available By studying the key event paths of probabilistic event structure graphs (PESGs, a key event path analysis approach for integrated system models is proposed. According to translation rules concluded from integrated system architecture descriptions, the corresponding PESGs are constructed from the colored Petri Net (CPN models. Then the definitions of cycle event paths, sequence event paths, and key event paths are given. Whereafter based on the statistic results after the simulation of CPN models, key event paths are found out by the sensitive analysis approach. This approach focuses on the logic structures of CPN models, which is reliable and could be the basis of structured analysis for discrete event systems. An example of radar model is given to characterize the application of this approach, and the results are worthy of trust.

  6. Events Marketing Model of Dubai Shopping Festival

    Directory of Open Access Journals (Sweden)

    K. Prakash Vel

    2014-12-01

    Full Text Available Cities and places have become major destinations through taking the extra mile of creativity and offering a well-researched package of offerings through systematically planned events. One such leading example in the list of successful festivals that have earned a global reputation due to its uniqueness and creative event offerings is the Dubai Shopping Festival (DSF in the United Arab Emirates. This paper is a case study based description of the internal and external drivers involved in planning and implementing a global event successfully and has captured the various drivers through a structured framework. The analysis serves as a good addition to the existing literature on ‘Events Marketing’. 

  7. Statistical analysis of solar proton events

    Directory of Open Access Journals (Sweden)

    V. Kurt

    2004-06-01

    Full Text Available A new catalogue of 253 solar proton events (SPEs with energy >10MeV and peak intensity >10 protons/cm2.s.sr (pfu at the Earth's orbit for three complete 11-year solar cycles (1970-2002 is given. A statistical analysis of this data set of SPEs and their associated flares that occurred during this time period is presented. It is outlined that 231 of these proton events are flare related and only 22 of them are not associated with Ha flares. It is also noteworthy that 42 of these events are registered as Ground Level Enhancements (GLEs in neutron monitors. The longitudinal distribution of the associated flares shows that a great number of these events are connected with west flares. This analysis enables one to understand the long-term dependence of the SPEs and the related flare characteristics on the solar cycle which are useful for space weather prediction.

  8. PRELIMINARY SELECTION OF MGR DESIGN BASIS EVENTS

    International Nuclear Information System (INIS)

    Kappes, J.A.

    1999-01-01

    The purpose of this analysis is to identify the preliminary design basis events (DBEs) for consideration in the design of the Monitored Geologic Repository (MGR). For external events and natural phenomena (e.g., earthquake), the objective is to identify those initiating events that the MGR will be designed to withstand. Design criteria will ensure that radiological release scenarios resulting from these initiating events are beyond design basis (i.e., have a scenario frequency less than once per million years). For internal (i.e., human-induced and random equipment failures) events, the objective is to identify credible event sequences that result in bounding radiological releases. These sequences will be used to establish the design basis criteria for MGR structures, systems, and components (SSCs) design basis criteria in order to prevent or mitigate radiological releases. The safety strategy presented in this analysis for preventing or mitigating DBEs is based on the preclosure safety strategy outlined in ''Strategy to Mitigate Preclosure Offsite Exposure'' (CRWMS M andO 1998f). DBE analysis is necessary to provide feedback and requirements to the design process, and also to demonstrate compliance with proposed 10 CFR 63 (Dyer 1999b) requirements. DBE analysis is also required to identify and classify the SSCs that are important to safety (ITS)

  9. Analysis of the Impact of External Debt on Economic Growth in an ...

    African Journals Online (AJOL)

    Analysis of the Impact of External Debt on Economic Growth in an Emerging Economy: Evidence from Nigeria. ... African Research Review ... Findings reveal that debt service payment has negative and insignificant impact on Nigeria's economic growth while external debt stock has positive and significant effect on Nigeria's ...

  10. Event History Analysis in Quantitative Genetics

    DEFF Research Database (Denmark)

    Maia, Rafael Pimentel

    Event history analysis is a clas of statistical methods specially designed to analyze time-to-event characteristics, e.g. the time until death. The aim of the thesis was to present adequate multivariate versions of mixed survival models that properly represent the genetic aspects related to a given...

  11. Experimental Characterization of a Grid-Loss Event on a 2.5-MW Dynamometer Using Advanced Operational Modal Analysis: Preprint

    Energy Technology Data Exchange (ETDEWEB)

    Helsen, J.; Weijtjens, W.; Guo, Y.; Keller, J.; McNiff, B.; Devriendt, C.; Guillaume, P.

    2015-02-01

    This paper experimentally investigates a worst case grid loss event conducted on the National Renewable Energy Laboratory (NREL) Gearbox Reliability Collaborative (GRC) drivetrain mounted on the 2.5MW NREL dynamic nacelle test-rig. The GRC drivetrain has a directly grid-coupled, fixed speed asynchronous generator. The main goal is the assessment of the dynamic content driving this particular assess the dynamic content of the high-speed stage of the GRC gearbox. In addition to external accelerometers, high frequency sampled measurements of strain gauges were used to assess torque fluctuations and bending moments both at the nacelle main shaft and gearbox high-speed shaft (HSS) through the entire duration of the event. Modal analysis was conducted using a polyreference Least Squares Complex Frequency-domain (pLSCF) modal identification estimator. The event driving the torsional resonance was identified. Moreover, the pLSCF estimator identified main drivetrain resonances based on a combination of acceleration and strain measurements. Without external action during the grid-loss event, a mode shape characterized by counter phase rotation of the rotor and generator rotor determined by the drivetrain flexibility and rotor inertias was the main driver of the event. This behavior resulted in significant torque oscillations with large amplitude negative torque periods. Based on tooth strain measurements of the HSS pinion, this work showed that at each zero-crossing, the teeth lost contact and came into contact with the backside flank. In addition, dynamic nontorque loads between the gearbox and generator at the HSS played an important role, as indicated by strain gauge-measurements.

  12. NPP unusual events: data, analysis and application

    International Nuclear Information System (INIS)

    Tolstykh, V.

    1990-01-01

    Subject of the paper are the IAEA cooperative patterns of unusual events data treatment and utilization of the operating safety experience feedback. The Incident Reporting System (IRS) and the Analysis of Safety Significant Event Team (ASSET) are discussed. The IRS methodology in collection, handling, assessment and dissemination of data on NPP unusual events (deviations, incidents and accidents) occurring during operations, surveillance and maintenance is outlined by the reports gathering and issuing practice, the experts assessment procedures and the parameters of the system. After 7 years of existence the IAEA-IRS contains over 1000 reports and receives 1.5-4% of the total information on unusual events. The author considers the reports only as detailed technical 'records' of events requiring assessment. The ASSET approaches implying an in-depth occurrences analysis directed towards level-1 PSA utilization are commented on. The experts evaluated root causes for the reported events and some trends are presented. Generally, internal events due to unexpected paths of water in the nuclear installations, occurrences related to the integrity of the primary heat transport systems, events associated with the engineered safety systems and events involving human factor represent the large groups deserving close attention. Personal recommendations on how to use the events related information use for NPP safety improvement are given. 2 tabs (R.Ts)

  13. Sensitivity studies on the approaches for addressing multiple initiating events in fire events PSA

    Energy Technology Data Exchange (ETDEWEB)

    Kang, Dae Il; Lim, Ho Gon [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2016-10-15

    A single fire event within a fire compartment or a fire scenario can cause multiple initiating events (IEs). As an example, a fire in a turbine building fire area can cause a loss of the main feed-water (LOMF) and loss of off-site power (LOOP) IEs. Previous domestic fire events PSA had considered only the most severe initiating event among multiple initiating events. NUREG/CR-6850 and ANS/ASME PRA Standard require that multiple IEs are to be addressed in fire events PSA. In this paper, sensitivity studies on the approaches for addressing multiple IEs in fire events PSA for Hanul Unit 3 were performed and their results were presented. In this paper, sensitivity studies on the approaches for addressing multiple IEs in fire events PSA are performed and their results were presented. From the sensitivity analysis results, we can find that the incorporations of multiple IEs into fire events PSA model result in the core damage frequency (CDF) increase and may lead to the generation of the duplicate cutsets. Multiple IEs also can occur at internal flooding event or other external events such as seismic event. They should be considered in the constructions of PSA models in order to realistically estimate risk due to flooding or seismic events.

  14. Sentiment analysis on tweets for social events

    DEFF Research Database (Denmark)

    Zhou, Xujuan; Tao, Xiaohui; Yong, Jianming

    2013-01-01

    Sentiment analysis or opinion mining is an important type of text analysis that aims to support decision making by extracting and analyzing opinion oriented text, identifying positive and negative opinions, and measuring how positively or negatively an entity (i.e., people, organization, event......, location, product, topic, etc.) is regarded. As more and more users express their political and religious views on Twitter, tweets become valuable sources of people's opinions. Tweets data can be efficiently used to infer people's opinions for marketing or social studies. This paper proposes a Tweets...... Sentiment Analysis Model (TSAM) that can spot the societal interest and general people's opinions in regard to a social event. In this paper, Australian federal election 2010 event was taken as an example for sentiment analysis experiments. We are primarily interested in the sentiment of the specific...

  15. Interpretation Analysis as a Competitive Event.

    Science.gov (United States)

    Nading, Robert M.

    Interpretation analysis is a new and interesting event on the forensics horizon which appears to be attracting an ever larger number of supporters. This event, developed by Larry Lambert of Ball State University in 1989, requires a student to perform all three disciplines of forensic competition (interpretation, public speaking, and limited…

  16. External analysis of the smartphone industry in Spain

    OpenAIRE

    Nájera Aragón, Fernando

    2014-01-01

    The main purpose of this end-of-grade project will be the external analysis of an industrial sector, in this case the Smartphone industry. The analysis will be based on Porter’s competitive force model, which allows us to study the competition among the sector and what companies are now leading the market and why. Although it is a market in continuous growth worldwide, this project will focus on how the smartphone market works in Spain. The project will be divided in four main parts, intro...

  17. Advanced event reweighting using multivariate analysis

    International Nuclear Information System (INIS)

    Martschei, D; Feindt, M; Honc, S; Wagner-Kuhr, J

    2012-01-01

    Multivariate analysis (MVA) methods, especially discrimination techniques such as neural networks, are key ingredients in modern data analysis and play an important role in high energy physics. They are usually trained on simulated Monte Carlo (MC) samples to discriminate so called 'signal' from 'background' events and are then applied to data to select real events of signal type. We here address procedures that improve this work flow. This will be the enhancement of data / MC agreement by reweighting MC samples on a per event basis. Then training MVAs on real data using the sPlot technique will be discussed. Finally we will address the construction of MVAs whose discriminator is independent of a certain control variable, i.e. cuts on this variable will not change the discriminator shape.

  18. Poisson-event-based analysis of cell proliferation.

    Science.gov (United States)

    Summers, Huw D; Wills, John W; Brown, M Rowan; Rees, Paul

    2015-05-01

    A protocol for the assessment of cell proliferation dynamics is presented. This is based on the measurement of cell division events and their subsequent analysis using Poisson probability statistics. Detailed analysis of proliferation dynamics in heterogeneous populations requires single cell resolution within a time series analysis and so is technically demanding to implement. Here, we show that by focusing on the events during which cells undergo division rather than directly on the cells themselves a simplified image acquisition and analysis protocol can be followed, which maintains single cell resolution and reports on the key metrics of cell proliferation. The technique is demonstrated using a microscope with 1.3 μm spatial resolution to track mitotic events within A549 and BEAS-2B cell lines, over a period of up to 48 h. Automated image processing of the bright field images using standard algorithms within the ImageJ software toolkit yielded 87% accurate recording of the manually identified, temporal, and spatial positions of the mitotic event series. Analysis of the statistics of the interevent times (i.e., times between observed mitoses in a field of view) showed that cell division conformed to a nonhomogeneous Poisson process in which the rate of occurrence of mitotic events, λ exponentially increased over time and provided values of the mean inter mitotic time of 21.1 ± 1.2 hours for the A549 cells and 25.0 ± 1.1 h for the BEAS-2B cells. Comparison of the mitotic event series for the BEAS-2B cell line to that predicted by random Poisson statistics indicated that temporal synchronisation of the cell division process was occurring within 70% of the population and that this could be increased to 85% through serum starvation of the cell culture. © 2015 International Society for Advancement of Cytometry.

  19. Engineering safety review mission Krsko NPP external events PSA. Ljubljana, Slovenia 19-23 February 1996. Final report

    International Nuclear Information System (INIS)

    Budnitz, R.J.; Smith, P.

    1996-01-01

    Within the scope of the TC Project RER/9/035, a review mission visited Ljubljana, Slovenia, 19-23 February 1996. Two outside experts, Messrs. R.J. Budnitz (USA) and Paul Smith (USA), as well as a staff member, A. Guerpinar (ESS-NSNI) took part in the review. The purpose of the mission was to assist the Slovenian Nuclear Safety Administration to review the external events PSA prepared by Krsko NPP consultants Westinghouse Energy Systems Europe and EQE International. Another seismic safety review was performed concurrently in Ljubljana involving the investigations in relation to the tectonic stability and reassessment of the design basis ground motion characterization for the Krsko NPP site

  20. Surface Management System Departure Event Data Analysis

    Science.gov (United States)

    Monroe, Gilena A.

    2010-01-01

    This paper presents a data analysis of the Surface Management System (SMS) performance of departure events, including push-back and runway departure events.The paper focuses on the detection performance, or the ability to detect departure events, as well as the prediction performance of SMS. The results detail a modest overall detection performance of push-back events and a significantly high overall detection performance of runway departure events. The overall detection performance of SMS for push-back events is approximately 55%.The overall detection performance of SMS for runway departure events nears 100%. This paper also presents the overall SMS prediction performance for runway departure events as well as the timeliness of the Aircraft Situation Display for Industry data source for SMS predictions.

  1. Life Cycle Assessment, ExternE and Comprehensive Analysis for an integrated evaluation of the environmental impact of anthropogenic activities

    Energy Technology Data Exchange (ETDEWEB)

    Pietrapertosa, F.; Cosmi, C. [National Research Council, Institute of Methodologies for Environmental Analysis C.N.R.-I.M.A.A. C.da S.Loja, I-85050 Tito Scalo (PZ) (Italy); National Research Council, National Institute for the Physics of Matter, C.N.R.-I.N.F.M. Via Cinthia, I-80126 Naples (Italy); Macchiato, M. [Federico II University, Department of Physical Sciences, Via Cinthia, I-80126 Naples (Italy); National Research Council, National Institute for the Physics of Matter, C.N.R.-I.N.F.M. Via Cinthia, I-80126 Naples (Italy); Salvia, M.; Cuomo, V. [National Research Council, Institute of Methodologies for Environmental Analysis C.N.R.-I.M.A.A. C.da S.Loja, I-85050 Tito Scalo (PZ) (Italy)

    2009-06-15

    The implementation of resource management strategies aimed at reducing the impacts of the anthropogenic activities system requires a comprehensive approach to evaluate on the whole the environmental burdens of productive processes and to identify the best recovery strategies from both an environmental and an economic point of view. In this framework, an analytical methodology based on the integration of Life Cycle Assessment (LCA), ExternE and Comprehensive Analysis was developed to perform an in-depth investigation of energy systems. The LCA methodology, largely utilised by the international scientific community for the assessment of the environmental performances of technologies, combined with Comprehensive Analysis allows modelling the overall system of anthropogenic activities, as well as sub-systems, the economic consequences of the whole set of environmental damages. Moreover, internalising external costs into partial equilibrium models, as those utilised by Comprehensive Analysis, can be useful to identify the best paths for implementing technology innovation and strategies aimed to a more sustainable energy supply and use. This paper presents an integrated application of these three methodologies to a local scale case study (the Val D'Agri area in Basilicata, Southern Italy), aimed to better characterise the environmental impacts of the energy system, with particular reference to extraction activities. The innovative methodological approach utilised takes advantage from the strength points of each methodology with an added value coming from their integration as emphasised by the main results obtained by the scenario analysis. (author)

  2. Frequency of forensic toxicological analysis in external cause deaths among nursing home residents: an analysis of trends.

    Science.gov (United States)

    Aitken, Georgia; Murphy, Briony; Pilgrim, Jennifer; Bugeja, Lyndal; Ranson, David; Ibrahim, Joseph Elias

    2017-03-01

    There is a paucity of research examining the utility of forensic toxicology in the investigation of premature external cause deaths of residents in nursing homes. The aim of this study is to describe the frequency and characteristics of toxicological analysis conducted in external cause (injury-related) deaths amongst nursing home residents in Victoria, Australia. This study was a retrospective cohort study examining external cause deaths among nursing home residents during the period July 1, 2000 to December 31, 2012 in Victoria, Australia, using the National Coronial Information System (NCIS). The variables examined comprised: sex, age group, year-of-death, cause and manner of death. One-third of deaths among nursing home residents in Victoria resulted from external causes (n = 1296, 33.3%) of which just over one-quarter (361, 27.9%) underwent toxicological analysis as part of the medical death investigation. The use of toxicological analysis varied by cause of death with a relatively low proportion conducted in deaths from unintentional falls (n = 286, 24.9%) and choking (n = 36, 40.4%). The use of toxicological analysis decreased as the decedents age increased. Forensic toxicology has the potential to contribute to improving our understanding of premature deaths in nursing home residents however it remains under used and is possibly undervalued.

  3. Second-order analysis of semiparametric recurrent event processes.

    Science.gov (United States)

    Guan, Yongtao

    2011-09-01

    A typical recurrent event dataset consists of an often large number of recurrent event processes, each of which contains multiple event times observed from an individual during a follow-up period. Such data have become increasingly available in medical and epidemiological studies. In this article, we introduce novel procedures to conduct second-order analysis for a flexible class of semiparametric recurrent event processes. Such an analysis can provide useful information regarding the dependence structure within each recurrent event process. Specifically, we will use the proposed procedures to test whether the individual recurrent event processes are all Poisson processes and to suggest sensible alternative models for them if they are not. We apply these procedures to a well-known recurrent event dataset on chronic granulomatous disease and an epidemiological dataset on meningococcal disease cases in Merseyside, United Kingdom to illustrate their practical value. © 2011, The International Biometric Society.

  4. RELAP5/MOD3.3 Analysis of the Loss of External Power Event with Safety Injection Actuation

    Directory of Open Access Journals (Sweden)

    Andrej Prošek

    2018-01-01

    Full Text Available The code assessment typically comprises basic tests cases, separate effects test, and integral effects tests. On the other hand, the thermal hydraulic system codes like RELAP5/MOD3.3 are primarily intended for simulation of transients and accidents in light water reactors. The plant measured data come mostly from startup tests and operational events. Also, for operational events the measured plant data may not be sufficient to explain all details of the event. The purpose of this study was therefore besides code assessment to demonstrate that simulations can be very beneficial for deep understanding of the plant response and further corrective measures. The abnormal event with reactor trip and safety injection signal actuation was simulated with the latest RELAP5/MOD3.3 Patch 05 best-estimate thermal hydraulic computer code. The measured and simulated data agree well considering the major plant system responses and operator actions. This suggests that the RELAP5 code simulation is good representative of the plant response and can complement not available information from plant measured data. In such a way, an event can be better understood.

  5. Estimating the impact of extreme events on crude oil price. An EMD-based event analysis method

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Xun; Wang, Shouyang [Institute of Systems Science, Academy of Mathematics and Systems Science, Chinese Academy of Sciences, Beijing 100190 (China); School of Mathematical Sciences, Graduate University of Chinese Academy of Sciences, Beijing 100190 (China); Yu, Lean [Institute of Systems Science, Academy of Mathematics and Systems Science, Chinese Academy of Sciences, Beijing 100190 (China); Lai, Kin Keung [Department of Management Sciences, City University of Hong Kong, Tat Chee Avenue, Kowloon (China)

    2009-09-15

    The impact of extreme events on crude oil markets is of great importance in crude oil price analysis due to the fact that those events generally exert strong impact on crude oil markets. For better estimation of the impact of events on crude oil price volatility, this study attempts to use an EMD-based event analysis approach for this task. In the proposed method, the time series to be analyzed is first decomposed into several intrinsic modes with different time scales from fine-to-coarse and an average trend. The decomposed modes respectively capture the fluctuations caused by the extreme event or other factors during the analyzed period. It is found that the total impact of an extreme event is included in only one or several dominant modes, but the secondary modes provide valuable information on subsequent factors. For overlapping events with influences lasting for different periods, their impacts are separated and located in different modes. For illustration and verification purposes, two extreme events, the Persian Gulf War in 1991 and the Iraq War in 2003, are analyzed step by step. The empirical results reveal that the EMD-based event analysis method provides a feasible solution to estimating the impact of extreme events on crude oil prices variation. (author)

  6. Estimating the impact of extreme events on crude oil price. An EMD-based event analysis method

    International Nuclear Information System (INIS)

    Zhang, Xun; Wang, Shouyang; Yu, Lean; Lai, Kin Keung

    2009-01-01

    The impact of extreme events on crude oil markets is of great importance in crude oil price analysis due to the fact that those events generally exert strong impact on crude oil markets. For better estimation of the impact of events on crude oil price volatility, this study attempts to use an EMD-based event analysis approach for this task. In the proposed method, the time series to be analyzed is first decomposed into several intrinsic modes with different time scales from fine-to-coarse and an average trend. The decomposed modes respectively capture the fluctuations caused by the extreme event or other factors during the analyzed period. It is found that the total impact of an extreme event is included in only one or several dominant modes, but the secondary modes provide valuable information on subsequent factors. For overlapping events with influences lasting for different periods, their impacts are separated and located in different modes. For illustration and verification purposes, two extreme events, the Persian Gulf War in 1991 and the Iraq War in 2003, are analyzed step by step. The empirical results reveal that the EMD-based event analysis method provides a feasible solution to estimating the impact of extreme events on crude oil prices variation. (author)

  7. A retrospective analysis of 140 dogs with oral melanoma treated with external beam radiation.

    Science.gov (United States)

    Proulx, David R; Ruslander, David M; Dodge, Richard K; Hauck, Marlene L; Williams, Laurel E; Horn, Birgitte; Price, G Sylvester; Thrall, Donald E

    2003-01-01

    Despite the early notion that canine oral malignant melanoma is radioresistant, recent data suggest that external beam radiotherapy is effective in local tumor control. However, optimal fractionation schedules have not been established. The high rate of regional and distant metastasis is another problem that has hindered long-term control. The role of chemotherapy in the management of canine oral melanoma has also not been determined. In this study, data from 140 dogs irradiated at North Carolina State University were evaluated with the following objectives: (1) to compare the efficacy of three radiation therapy protocols (36 Gy, 9 Gy x 4 fractions; 30 Gy, 10 Gy x 3 fractions; or >45 Gy, 2-4 Gy x 12-19 fractions) for the treatment of dogs with oral malignant melanoma, (2) to identify any host or tumor factors influencing prognosis, and (3) to determine the impact of systemic chemotherapy on treatment outcome. Information regarding response to therapy, disease progression, and survival were determined from the medical records or from information obtained by telephone or mail survey. Relationships between host, tumor, and treatment variables and outcome measures (response, time to first event, and survival) were evaluated using Fisher's exact test (response) and the Cox regression model (time to first event and survival). The median time to first event for the 140 dogs was 5.0 months (95% C.I., 4-6 months) and the median survival was 7.0 months (95% C.I., 6-9 months). In the univariate analysis, the following variables were associated with increased time to first event and survival: (1) rostral tumor sublocation; (2) lack of bone lysis observed on skull imaging, and (3) microscopic tumor burden. In a multivariate analysis of 111 dogs with complete data for these variables, tumor sublocation, bone lysis, and tumor volume were identified as joint predictors of time to first event (p oral malignant melanoma; however, the optimal fractionation scheme has yet to be

  8. Summary report of already existing guidance on the implementation of External Hazards in extended Level 1 PSA

    International Nuclear Information System (INIS)

    Klug, J.; Kumar, M.; Prochaska, J.; Brac, P.; Vasseur, D.; Brinkman, H.; Kahia, S.; Nitoi, Mirela; Apostol, M.; Georgescu, G.; Volkanovski, Andrija; Mustoe, J.; Alzbutas, R.; La Rovere, S.

    2015-08-01

    The report provides a summary of already existing guidance on the implementation of external hazards in extended level 1 PSA. It summarized the lessons learnt from existing standards, existing gaps and possibility for future development within the work-package WP22 'How to introduce hazards in L1 PSA and all possibilities of events combinations'. The report is focused on the four following areas, for several hazards: 1) Impact on the SSCs modelled in L1 PSA event trees; 2) Impact on Human Reliability Assessment modelling in L1 PSA; 3) Site impact modelling in L1 PSA event trees; 4) Link between external initiating events of PSA and NPP design basis conditions. During the review of existing guidance, it appeared that many of the references form a suitable basis to introduce external hazards in L1 PSA including event combination. Available guidelines provide usable recommendations to evaluate failure probabilities of SSCs depending on the influence of single hazard or events combination. The most detailed guidelines are devoted to the seismic events and fires. Even if these guidelines deal only with single event impact, they can be also used for combined events purpose to evaluate particular effects induced by analyzed external hazards. Guidelines provide general systematic framework how to determine the scope of SSCs for extended PSA and failure modes (develop an extended list of components). In general available guidelines provide detailed framework for analysis of seismic event. The other external hazards are not always covered so deeply. This is probably caused by specific site nature of these hazards like external floods, fires etc. In case of HRA, more detailed information and HRA models are available for seismic events or fire events. For the other external hazards, the literature with regard to HRA is not well developed. The PSA for external hazards should take account the potential for human response to be affected by the external event. More realistic Human

  9. External beam PIXE analysis of painting

    International Nuclear Information System (INIS)

    Pascholati, Paulo R.; Rizzutto, Marcia A.; Barbosa, Marcel D.L.; Albuquerque, Cindy

    2005-01-01

    The preservation and conservation of mankind cultural heritage has become an important issue worldwide. Non-destructive analytical techniques are suitable, for example, to analyze precious and unique objects of art and archaeology. Among those techniques Particle Induced X-Ray Emission (PIXE) has good advantage to identify elemental composition present in these kinds of objects. The Laboratorio de Analise de Materiais por Feixes Ionicos-LAMFI of the Institute of Physics of the University of Sao Paulo has been installed an external beam facility for PIXE analysis. This new setup is being used for the analysis of archaeological pottery artifacts, paintings and biological tissues (teeth and bones), which are not compatible with the high vacuum of the regular PIXE target chamber. In addition most art and archaeological objects are too large for the evacuated analysis chamber. Applications of this facility will be presented in the analysis of one painting of the beginning of the last century. The chemical elements identified in the painting were Ca, Ti, Cr, Cu, Fe, Zn, Pb and Ba. The PIXE measurements were done non-destructively and no visible damage was observed on the irradiated object. (author)

  10. Probabilistic Safety Assessment (PSA) of Natural External Hazards Including Earthquakes. Workshop Proceedings, Prague, Czech Republic, 17-20 June 2013

    International Nuclear Information System (INIS)

    2014-01-01

    external hazards, including combinations of those hazards, and their impacts. It is important that such an analysis covers not only individual plant units, but also the site as a whole, including all dependent effects and impacts. - While systematic approaches for addressing external hazards in PSA currently exist and there is a well-developed state-of-practice (e.g., with respect to external flooding, seismic, high winds), additional work is needed; for example, the use of conservative approaches to address uncertainties might be practical, but more realistic evaluations provide better view on the real problems. - Some methods and guides are available for seismic hazard determination, identification of external hazards, screening of external events for detailed consequence analysis, including several lists of screening criteria. However, additional development is also needed in area of consensus standards and guides; for example IAEA continues developing the methodological support for external hazards analysis. - The major areas of concern in external hazards studies are: 1. Scope of the PSA for external events in terms of plant operation regimes (e.g., full power, low power and shutdown operational states), 2. Combinations of external hazards impacts, 3. Multi-unit impacts, and 4. Screening procedure for site specific hazards. - The following are significance technical/methodological challenges for external hazard PSA: 1) Fragility analysis of non-seismic external hazards, 2) Correlation effects and consequent damage scenarios, 3) Human Reliability Analysis (HRA) for external events PSA, 4) PSA mission times for long-term external event scenarios, and 5) Significance and magnitude of the effects of climate changes on the hazard frequencies and magnitudes. - The following aspects are considered to be important good practice attributes for external hazard modeling in PRA: 1) Critically challenging assumptions, 2) Calibrating models, 3) Accounting for underlying physical

  11. Dynamic Event Tree Analysis Through RAVEN

    Energy Technology Data Exchange (ETDEWEB)

    A. Alfonsi; C. Rabiti; D. Mandelli; J. Cogliati; R. A. Kinoshita; A. Naviglio

    2013-09-01

    Conventional Event-Tree (ET) based methodologies are extensively used as tools to perform reliability and safety assessment of complex and critical engineering systems. One of the disadvantages of these methods is that timing/sequencing of events and system dynamics is not explicitly accounted for in the analysis. In order to overcome these limitations several techniques, also know as Dynamic Probabilistic Risk Assessment (D-PRA), have been developed. Monte-Carlo (MC) and Dynamic Event Tree (DET) are two of the most widely used D-PRA methodologies to perform safety assessment of Nuclear Power Plants (NPP). In the past two years, the Idaho National Laboratory (INL) has developed its own tool to perform Dynamic PRA: RAVEN (Reactor Analysis and Virtual control ENvironment). RAVEN has been designed in a high modular and pluggable way in order to enable easy integration of different programming languages (i.e., C++, Python) and coupling with other application including the ones based on the MOOSE framework, developed by INL as well. RAVEN performs two main tasks: 1) control logic driver for the new Thermo-Hydraulic code RELAP-7 and 2) post-processing tool. In the first task, RAVEN acts as a deterministic controller in which the set of control logic laws (user defined) monitors the RELAP-7 simulation and controls the activation of specific systems. Moreover, RAVEN also models stochastic events, such as components failures, and performs uncertainty quantification. Such stochastic modeling is employed by using both MC and DET algorithms. In the second task, RAVEN processes the large amount of data generated by RELAP-7 using data-mining based algorithms. This paper focuses on the first task and shows how it is possible to perform the analysis of dynamic stochastic systems using the newly developed RAVEN DET capability. As an example, the Dynamic PRA analysis, using Dynamic Event Tree, of a simplified pressurized water reactor for a Station Black-Out scenario is presented.

  12. Possibilities and conditions of applying PIXE analysis with external proton beam

    International Nuclear Information System (INIS)

    Potocek, V.

    1989-01-01

    The technical and methodological prerequisites are summed up for the use of the PIXE method with an external proton beam. The method is suitable for the preliminary analysis of unknown samples prior to the choice of the best suited analytical method, for the nondestructive analysis of rare samples such as unique works of art, of small amounts of materials which are difficult to access, etc., as well as for calibration and comparing analyses. As for the operators the application of the PIXE method with external proton beam assumes the availability of accelerator operating time, minimization of the length of exposure of the targets, optimization of parameters of the exciting beam and automation of the whole process. Attention is also devoted to technical provisions and organization of laboratory work. The design is described of an analytical unit using the PIXE method with external proton beam, and it is stated that the Van de Graaff accelerator at the Institute of Nuclear Physics in Rez near Prague could be used for the purpose. (Z.M.). 6 refs

  13. Top event prevention analysis: A deterministic use of PRA

    International Nuclear Information System (INIS)

    Worrell, R.B.; Blanchard, D.P.

    1996-01-01

    This paper describes the application of Top Event Prevention Analysis. The analysis finds prevention sets which are combinations of basic events that can prevent the occurrence of a fault tree top event such as core damage. The problem analyzed in this application is that of choosing a subset of Motor-Operated Valves (MOVs) for testing under the Generic Letter 89-10 program such that the desired level of safety is achieved while providing economic relief from the burden of testing all safety-related valves. A brief summary of the method is given, and the process used to produce a core damage expression from Level 1 PRA models for a PWR is described. The analysis provides an alternative to the use of importance measures for finding the important combination of events in a core damage expression. This application of Top Event Prevention Analysis to the MOV problem was achieve with currently available software

  14. Effect of regional anesthesia on the success rate of external cephalic version: a systematic review and meta-analysis.

    Science.gov (United States)

    Goetzinger, Katherine R; Harper, Lorie M; Tuuli, Methodius G; Macones, George A; Colditz, Graham A

    2011-11-01

    To estimate whether the use of regional anesthesia is associated with increased success of external cephalic version. We searched MEDLINE, EMBASE, the Cochrane Library, and clinical trial registries. Electronic databases were searched from 1966 through April 2011 for published, randomized controlled trials in the English language comparing regional anesthesia with no regional anesthesia for external cephalic version. The primary outcome was external cephalic version success. Secondary outcomes included cesarean delivery, maternal discomfort, and adverse events. Pooled risk ratios (relative risk) were calculated using a random-effects model. Heterogeneity was assessed using the Cochran's Q statistic and quantified using the I Z method. Six randomized controlled trials met criteria for study inclusion. Regional anesthesia was associated with a higher external cephalic version success rate compared with intravenous or no analgesia (59.7% compared with 37.6%; pooled relative risk 1.58; 95% confidence interval [CI] 1.29-1.93). This significant association persisted when the data were stratified by type of regional anesthesia (spinal compared with epidural). The number needed to treat with regional anesthesia to achieve one additional successful external cephalic version was five. There was no evidence of statistical heterogeneity (P=.32, I Z=14.9%) or publication bias (Harbord test P=.78). There was no statistically significant difference in the risk of cesarean delivery comparing regional anesthesia with intravenous or no analgesia (48.4% compared with 59.3%; pooled relative risk 0.80; 95% CI 0.55-1.17). Adverse events were rare and not significantly different between the two groups. Regional anesthesia is associated with a higher success rate of external cephalic version.

  15. Accident analyses in nuclear power plants following external initiating events and in the shutdown state. Final report; Unfallanalysen in Kernkraftwerken nach anlagenexternen ausloesenden Ereignissen und im Nichtleistungsbetrieb. Abschlussbericht

    Energy Technology Data Exchange (ETDEWEB)

    Loeffler, Horst; Kowalik, Michael; Mildenberger, Oliver; Hage, Michael

    2016-06-15

    The work which is documented here provides the methodological basis for improvement of the state of knowledge for accident sequences after plant external initiating events and for accident sequences which begin in the shutdown state. The analyses have been done for a PWR and for a BWR reference plant. The work has been supported by the German federal ministry BMUB under the label 3612R01361. Top objectives of the work are: - Identify relevant event sequences in order to define characteristic initial and boundary conditions - Perform accident analysis of selected sequences - Evaluate the relevance of accident sequences in a qualitative way The accident analysis is performed with the code MELCOR 1.8.6. The applied input data set has been significantly improved compared to previous analyses. The event tree method which is established in PSA level 2 has been applied for creating a structure for a unified summarization and evaluation of the results from the accident analyses. The computer code EVNTRE has been applied for this purpose. In contrast to a PSA level 2, the branching probabilities of the event tree have not been determined with the usual accuracy, but they are given in an approximate way only. For the PWR, the analyses show a considerable protective effect of the containment also in the case of beyond design events. For the BWR, there is a rather high probability for containment failure under core melt impact, but nevertheless the release of radionuclides into the environment is very limited because of plant internal retention mechanisms. This report concludes with remarks about existing knowledge gaps and with regard to core melt sequences, and about possible improvements of the plant safety.

  16. External pancreatic duct stent reduces pancreatic fistula: a meta-analysis and systematic review.

    Science.gov (United States)

    Patel, Krishen; Teta, Anthony; Sukharamwala, Prashant; Thoens, Jonathan; Szuchmacher, Mauricio; DeVito, Peter

    2014-01-01

    Postoperative pancreatic fistula formation (POPF) remains one of the most common and detrimental complications following pancreaticojejunostomy (PJ). The aim of this meta-analysis is to analyze the efficacy of external pancreatic duct stent placement in preventing POPF formation following PJ. The primary end-point was the incidence of POPF formation following pancreaticoduodenectomy (PD) in the presence and absence of external stent placement. Secondary outcomes examined were the incidence of perioperative mortality, delayed gastric emptying, postoperative wound infection, operative time, blood loss, and length of hospital stay. Four trials were included comprising 416 patients. External pancreatic duct stenting was found to reduce the incidence of both any grade POPF formation (OR 0.37, 95% CI = 0.23 to 0.58, p = 0.0001) and clinically significant (grade B or C) POPF formation (OR 0.50, 95% CI = 0.30 to 0.84, p = 0.0009) following PD. The use of an external stent was also found to significantly lessen length of hospital stay (SMD -0.39, 95% CI = -0.63 to -0.15, p = 0.001). This analysis has shown that external pancreatic duct stenting is indeed efficacious in the incidence of both any grade as well as clinically significant POPF formation following PD. Length of hospital stay was also found to be significantly less by external duct stenting. Copyright © 2014 Surgical Associates Ltd. Published by Elsevier Ltd. All rights reserved.

  17. Design basis event consequence analyses for the Yucca Mountain project

    International Nuclear Information System (INIS)

    Orvis, D.D.; Haas, M.N.; Martin, J.H.

    1997-01-01

    Design basis event (DBE) definition and analysis is an ongoing and integrated activity among the design and analysis groups of the Yucca Mountain Project (YMP). DBE's are those that potentially lead to breach of the waste package and waste form (e.g., spent fuel rods) with consequent release of radionuclides to the environment. A Preliminary Hazards Analysis (PHA) provided a systematic screening of external and internal events that were candidate DBE's that will be subjected to analyses for radiological consequences. As preparation, pilot consequence analyses for the repository subsurface and surface facilities have been performed to define the methodology, data requirements, and applicable regulatory limits

  18. The analysis of the initiating events in thorium-based molten salt reactor

    International Nuclear Information System (INIS)

    Zuo Jiaxu; Song Wei; Jing Jianping; Zhang Chunming

    2014-01-01

    The initiation events analysis and evaluation were the beginning of nuclear safety analysis and probabilistic safety analysis, and it was the key points of the nuclear safety analysis. Currently, the initiation events analysis method and experiences both focused on water reactor, but no methods and theories for thorium-based molten salt reactor (TMSR). With TMSR's research and development in China, the initiation events analysis and evaluation was increasingly important. The research could be developed from the PWR analysis theories and methods. Based on the TMSR's design, the theories and methods of its initiation events analysis could be researched and developed. The initiation events lists and analysis methods of the two or three generation PWR, high-temperature gascooled reactor and sodium-cooled fast reactor were summarized. Based on the TMSR's design, its initiation events would be discussed and developed by the logical analysis. The analysis of TMSR's initiation events was preliminary studied and described. The research was important to clarify the events analysis rules, and useful to TMSR's designs and nuclear safety analysis. (authors)

  19. Event analysis in a primary substation

    Energy Technology Data Exchange (ETDEWEB)

    Jaerventausta, P; Paulasaari, H [Tampere Univ. of Technology (Finland); Partanen, J [Lappeenranta Univ. of Technology (Finland)

    1998-08-01

    The target of the project was to develop applications which observe the functions of a protection system by using modern microprocessor based relays. Microprocessor based relays have three essential capabilities: communication with the SCADA, the internal clock to produce time stamped event data, and the capability to register certain values during the fault. Using the above features some new functions for event analysis were developed in the project

  20. A study of risk evaluation methodology selection for the external hazards

    International Nuclear Information System (INIS)

    Kuramoto, Takahiro; Yamaguchi, Akira; Narumiya, Yosiyuki

    2014-01-01

    Since the accident at Fukushima Daiichi Nuclear Power Plant caused by the Great East Japan Earthquake in March 2011, there has been growing demands for assessing the effects of external hazards, including natural events, such as earthquake and tsunami, and external human behaviors, and taking actions to address those external hazards. The newly established Japanese regulatory requirements claim design considerations associated with external hazards. The primary objective of the risk assessment for external hazards is to establish countermeasures against such hazards rather than grasping the risk figures. Therefore, applying detailed risk assessment methods, such as probabilistic risk assessment (PRA), to all the external hazards is not always the most appropriate. Risk assessment methods can vary in types including qualitative evaluation, hazard analysis (analyzing hazard frequencies or their influence), and margin assessment. To resolve these issues, a process has been established that enables us to identify the external hazards in a comprehensive and systematic manner, which have potential risks leading to core damage and to select an appropriate evaluation method according to the risks associated with each of the external hazards. This paper discusses the comprehensive and systematic identification process for the external hazards which have potential risks leading to core damage, and the approaches of selecting an appropriate evaluation method for each external hazard. This paper also describes some applications of specific risk evaluation methods. (author)

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

    International Nuclear Information System (INIS)

    Kimura, C.Y.; Budnitz, R.J.

    1987-12-01

    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 externally initiated events. The broad objective has been to gain an understanding of whether or not each external initiator is 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. Four external hazards were investigated in this report. These external hazards are internal fires, high winds/tornadoes, external floods, and transportation accidents. 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. Using these two figures-of-merit as evaluation criteria, it has been feasible to ascertain whether the risk from externally initiated accidents is, or is not, an important contributor to overall risk for the US nuclear power plants studied. This has been accomplished for each initiator separately. 208 refs., 17 figs., 45 tabs

  2. Increased pain relief with remifentanil does not improve the success rate of external cephalic version: a randomized controlled trial.

    Science.gov (United States)

    Burgos, Jorge; Pijoan, José I; Osuna, Carmen; Cobos, Patricia; Rodriguez, Leire; Centeno, María del Mar; Serna, Rosa; Jimenez, Antonia; Garcia, Eugenia; Fernandez-Llebrez, Luis; Melchor, Juan C

    2016-05-01

    Our objective was to compare the effect of two pain relief methods (remifentanil vs. nitrous oxide) on the success rate of external cephalic version. We conducted a randomized open label parallel-group controlled single-center clinical trial with sequential design, at Cruces University Hospital, Spain. Singleton pregnancies in noncephalic presentation at term that were referred for external cephalic version were assigned according to a balanced (1:1) restricted randomization scheme to analgesic treatment with remifentanil or nitrous oxide during the procedure. The primary endpoint was external cephalic version success rate. Secondary endpoints were adverse event rate, degree of pain, cesarean rate and perinatal outcomes. The trial was stopped early after the second interim analysis due to a very low likelihood of finding substantial differences in efficacy (futility). The external cephalic version success rate was the same in the two arms (31/60, 51.7%) with 120 women recruited, 60 in each arm. The mean pain score was significantly lower in the remifentanil group (3.2 ± 2.4 vs. 6.0 ± 2.3; p external cephalic version-related complications. There was a trend toward a higher frequency of adverse effects in the remifentanil group (18.3% vs. 6.7%, p = 0.10), with a significantly higher incidence rate (21.7 events/100 women vs. 6.7 events/100 women with nitrous oxide, p = 0.03). All reported adverse events were mild and reversible. Remifentanil for analgesia decreased external cephalic version-related pain but did not increase the success rate of external cephalic version at term and appeared to be associated with an increased frequency of mild adverse effects. © 2016 Nordic Federation of Societies of Obstetrics and Gynecology.

  3. Data analysis of event tape and connection

    International Nuclear Information System (INIS)

    Gong Huili

    1995-01-01

    The data analysis on the VAX-11/780 computer is briefly described, the data is from the recorded event tape of JUHU data acquisition system on the PDP-11/44 computer. The connection of the recorded event tapes of the XSYS data acquisition system on VAX computer is also introduced

  4. ANALYSIS OF EVENT TOURISM IN RUSSIA, ITS FUNCTIONS, WAYS TO IMPROVE THE EFFICIENCY OF EVENT

    Directory of Open Access Journals (Sweden)

    Mikhail Yur'evich Grushin

    2016-01-01

    Full Text Available This article considers one of the important directions of development of the national economy in the area of tourist services – development of event tourism in the Russian Federation. Today the market of event management in Russia is in the process of formation, therefore its impact on the socio-economic development of regions and Russia as a whole is minimal, and the analysis of the influence is not performed. This problem comes to the fore in the regions of Russia, specializing in the creation of event-direction tourist-recreational cluster. The article provides an analysis of the existing market of event management and event tourism functions. Providing the ways to improve the efficiency of event management and recommendations for the organizer of events in the regions. The article shows the specific role of event tourism in the national tourism and provides direction for the development of organizational and methodical recommendations on its formation in the regions of Russia and the creation of an effective management system at the regional level. The purpose of this article is to analyze the emerging in Russia event tourism market and its specifics. On the basis of these studies are considered folding patterns of the new market and the assessment of its impact on the modern national tourism industry. Methodology. To complete this article are used comparative and economic and statistical analysis methods. Conclusions/significance. The practical importance of this article is in the elimination of existing in the national tourism industry contradictions: on the one hand, in the Russian Federation is annually held a large amount events activities, including world-class in all regions say about tourist trips to the event, but the event tourism does not exist yet. In all regions, there is an internal and inbound tourism, but it has nothing to do with the event tourism. The article has a practical conclusions demonstrate the need to adapt the

  5. ExternE: Externalities of energy Vol. 1. Summary

    International Nuclear Information System (INIS)

    Holland, M.; Berry, J.

    1995-01-01

    There is a growing requirement for policy analysts to take account of the environment in their decision making and to undertake the specified cost-benefit analysis. Within the European Union this is reflected in the 5th Environmental Action Programme, and the Commission's White Paper entitled 'Growth, competitiveness, employment and the ways forward to the 21st century'. This has led to a need for evaluation of environmental externalities. The ExternE Project commenced in 1991 as the European part of a collaborative study between the European Commission and the US Department of Energy. It aims to be the first systematic approach to the evaluation of external costs of a wide range of different fuel cycles. The project will result in an operational accounting framework for the quantification and monetarisation of priority environmental and other externalities. This framework will allow the calculation of the marginal external costs and benefits for specific power plants, at specific sites using specified technologies. There are three major phases in the project. Phase 1 was undertaken in collaboration with the US Department of Energy. In this phase the teams jointly developed the conceptual approach and methodology and shared scientific information for application to a number of fuel cycles. On the European side work concentrated on the nuclear and coal fuel cycles which together were expected to raise many of the fundamental issues in fuel cycle analysis. The project is currently nearing completion of Phase 2. During this phase the methodology has been applied to a wide range of different fossil, nuclear and renewable fuel cycles for power generation and energy conservation options. Also a series of National Implementation Programmes is underway in which the methodology and accounting framework are being applied to reference sites throughout Europe. In addition the general methodology is being extended to address the evaluation of externalities associated with

  6. Repeated Time-to-event Analysis of Consecutive Analgesic Events in Postoperative Pain

    DEFF Research Database (Denmark)

    Juul, Rasmus Vestergaard; Rasmussen, Sten; Kreilgaard, Mads

    2015-01-01

    BACKGROUND: Reduction in consumption of opioid rescue medication is often used as an endpoint when investigating analgesic efficacy of drugs by adjunct treatment, but appropriate methods are needed to analyze analgesic consumption in time. Repeated time-to-event (RTTE) modeling is proposed as a way...... to describe analgesic consumption by analyzing the timing of consecutive analgesic events. METHODS: Retrospective data were obtained from 63 patients receiving standard analgesic treatment including morphine on request after surgery following hip fracture. Times of analgesic events up to 96 h after surgery...... were extracted from hospital medical records. Parametric RTTE analysis was performed with exponential, Weibull, or Gompertz distribution of analgesic events using NONMEM®, version 7.2 (ICON Development Solutions, USA). The potential influences of night versus day, sex, and age were investigated...

  7. Computer-aided event tree analysis by the impact vector method

    International Nuclear Information System (INIS)

    Lima, J.E.P.

    1984-01-01

    In the development of the Probabilistic Risk Analysis of Angra I, the ' large event tree/small fault tree' approach was adopted for the analysis of the plant behavior in an emergency situation. In this work, the event tree methodology is presented along with the adaptations which had to be made in order to attain a correct description of the safety system performances according to the selected analysis method. The problems appearing in the application of the methodology and their respective solutions are presented and discussed, with special emphasis to the impact vector technique. A description of the ETAP code ('Event Tree Analysis Program') developed for constructing and quantifying event trees is also given in this work. A preliminary version of the small-break LOCA analysis for Angra 1 is presented as an example of application of the methodology and of the code. It is shown that the use of the ETAP code sigmnificantly contributes to decreasing the time spent in event tree analyses, making it viable the practical application of the analysis approach referred above. (author) [pt

  8. Design basis II: Design for events

    International Nuclear Information System (INIS)

    Frisch, W.

    1982-01-01

    In a lecture of this title, it could be expected that all events which are a basis for system and component design are described. According to the title of the Course 'Instrumentation and Control of Nuclear Power Plants' emphasis is put on events originating within the plant (no consideration of external events such as air plane crash or earth-quake). The lecture is divided into the two parts 'Transients' and 'Loss of coolant accidents (LOCAs)'. Due to the complex interaction between systems and components during transients, the first part is the main part of the lecture, while the second part (LOCAs) is only a very brief description of emergency core cooling system functions and the typical course of a large and small LOCA event. The first part on anticipated transients with intact primary coolant system boundary (non-LOCA-transients) covers several aspects of the analysis, such as classification, brief system description, transient description, analysis of anticipated transients without scram (ATWS) and analytical methods. Due to the time restriction necessary within the course, only a small section of the entire area can be presented in this paper. (orig.)

  9. Probabilistic safety assessment for seismic events

    International Nuclear Information System (INIS)

    1993-10-01

    This Technical Document on Probabilistic Safety Assessment for Seismic Events is mainly associated with the Safety Practice on Treatment of External Hazards in PSA and discusses in detail one specific external hazard, i.e. earthquakes

  10. Trending analysis of precursor events

    International Nuclear Information System (INIS)

    Watanabe, Norio

    1998-01-01

    The Accident Sequence Precursor (ASP) Program of United States Nuclear Regulatory Commission (U.S.NRC) identifies and categorizes operational events at nuclear power plants in terms of the potential for core damage. The ASP analysis has been performed on yearly basis and the results have been published in the annual reports. This paper describes the trends in initiating events and dominant sequences for 459 precursors identified in the ASP Program during the 1969-94 period and also discusses a comparison with dominant sequences predicted in the past Probabilistic Risk Assessment (PRA) studies. These trends were examined for three time periods, 1969-81, 1984-87 and 1988-94. Although the different models had been used in the ASP analyses for these three periods, the distribution of precursors by dominant sequences show similar trends to each other. For example, the sequences involving loss of both main and auxiliary feedwater were identified in many PWR events and those involving loss of both high and low coolant injection were found in many BWR events. Also, it was found that these dominant sequences were comparable to those determined to be dominant in the predictions by the past PRAs. As well, a list of the 459 precursors identified are provided in Appendix, indicating initiating event types, unavailable systems, dominant sequences, conditional core damage probabilities, and so on. (author)

  11. European regional efficiency and geographical externalities: a spatial nonparametric frontier analysis

    Science.gov (United States)

    Ramajo, Julián; Cordero, José Manuel; Márquez, Miguel Ángel

    2017-10-01

    This paper analyses region-level technical efficiency in nine European countries over the 1995-2007 period. We propose the application of a nonparametric conditional frontier approach to account for the presence of heterogeneous conditions in the form of geographical externalities. Such environmental factors are beyond the control of regional authorities, but may affect the production function. Therefore, they need to be considered in the frontier estimation. Specifically, a spatial autoregressive term is included as an external conditioning factor in a robust order- m model. Thus we can test the hypothesis of non-separability (the external factor impacts both the input-output space and the distribution of efficiencies), demonstrating the existence of significant global interregional spillovers into the production process. Our findings show that geographical externalities affect both the frontier level and the probability of being more or less efficient. Specifically, the results support the fact that the spatial lag variable has an inverted U-shaped non-linear impact on the performance of regions. This finding can be interpreted as a differential effect of interregional spillovers depending on the size of the neighboring economies: positive externalities for small values, possibly related to agglomeration economies, and negative externalities for high values, indicating the possibility of production congestion. Additionally, evidence of the existence of a strong geographic pattern of European regional efficiency is reported and the levels of technical efficiency are acknowledged to have converged during the period under analysis.

  12. Serious adverse events with infliximab: analysis of spontaneously reported adverse events.

    Science.gov (United States)

    Hansen, Richard A; Gartlehner, Gerald; Powell, Gregory E; Sandler, Robert S

    2007-06-01

    Serious adverse events such as bowel obstruction, heart failure, infection, lymphoma, and neuropathy have been reported with infliximab. The aims of this study were to explore adverse event signals with infliximab by using a long period of post-marketing experience, stratifying by indication. The relative reporting of infliximab adverse events to the U.S. Food and Drug Administration (FDA) was assessed with the public release version of the adverse event reporting system (AERS) database from 1968 to third quarter 2005. On the basis of a systematic review of adverse events, Medical Dictionary for Regulatory Activities (MedDRA) terms were mapped to predefined categories of adverse events, including death, heart failure, hepatitis, infection, infusion reaction, lymphoma, myelosuppression, neuropathy, and obstruction. Disproportionality analysis was used to calculate the empiric Bayes geometric mean (EBGM) and corresponding 90% confidence intervals (EB05, EB95) for adverse event categories. Infliximab was identified as the suspect medication in 18,220 reports in the FDA AERS database. We identified a signal for lymphoma (EB05 = 6.9), neuropathy (EB05 = 3.8), infection (EB05 = 2.9), and bowel obstruction (EB05 = 2.8). The signal for granulomatous infections was stronger than the signal for non-granulomatous infections (EB05 = 12.6 and 2.4, respectively). The signals for bowel obstruction and infusion reaction were specific to patients with IBD; this suggests potential confounding by indication, especially for bowel obstruction. In light of this additional evidence of risk of lymphoma, neuropathy, and granulomatous infections, clinicians should stress this risk in the shared decision-making process.

  13. Effect of enhanced external counterpulsation therapy on myeloperoxidase in lowering cardiovascular events of patients with chronic heart failure

    Directory of Open Access Journals (Sweden)

    Starry H. Rampengan

    2013-08-01

    Full Text Available Background: Chronic heart failure (CHF is a slowly progressive disease with high morbidity and mortality; therefore, the management using pharmacological treatments frequently fails to improve outcome. Enhanced external counterpulsation (EECP, a non-invasive treatment, may serve as alternative treatment for heart failure. This study was aimed to evaluate the influence of EECP on myeloperoxidase (MPO as inflammatory marker as well as cardiac events outcome.Methods: This was an open randomized controlled clinical trial on 66 CHF patients visiting several cardiovascular clinics in Manado between January-December 2012. The subjects were randomly divided into two groups, i.e. the group who receive EECP therapy and those who did not receive EECP therapy with 33 patients in each group. Myeloperoxidase (MPO as inflammatory marker was examined at baseline and after 6 months of observation. Cardiovascular events were observed as well after 6 months of observation. Unpaired t-test was use to analyze the difference of MPO between the two groups, and chi-square followed by calculation of relative risk were used for estimation of cardiovascular event outcomes.Results: MPO measurement at baseline and after 6 months in EECP group were 643.16 ± 239.40 pM and 422.31 ± 156.26 pM, respectively (p < 0.001. Whereas in non EECP group, the MPO values were 584.69 ± 281.40 pM and 517.64 ± 189.68 pM, repectively (p = 0.792. MPO reduction was observed in all patients of EECP group and in 13 patients (48% of non-EECP group (p < 0.001. Cardiovascular events were observed in 7 (21.21% and 15 (45.45% of patients in EECP and non-EECP groups, respectively (p = 0.037.Conclusion: EECP therapy significantly decreased the level of MPO as inflammatory marker and this decrease was correlated with the reduction of cardiovascular events in CHF patients. (Med J Indones. 2013;22:152-60. doi: 10.13181/mji.v22i3.584Keywords: CHF, cardiovascular events, EECP, myeloperoxidase

  14. Externalities of fuel cycles 'ExternE' project. Summary report

    International Nuclear Information System (INIS)

    Holland, M.; Berry, J.

    1994-01-01

    There is a growing requirement for policy analysts to take account of the environment in their decision making and to undertake the specified cost-benefit analysis. Within the European Union this is reflected in the 5th Environmental Action Programme, and the Commission's White Paper entitled 'Growth, competitiveness, employment and the ways forward to the 21st century'. This has led to a need for evaluation of environmental externalities. The ExternE Project commenced in 1991 as the European part of a collaborative study between the European Commission and the US Department of Energy. It aims to be the first systematic approach to the evaluation of external costs of a wide range of different fuel cycles. The project will result in an operational accounting framework for the quantification and monetarisation of priority environmental and other externalities. This framework will allow the calculation of the marginal external costs and benefits for specific power plants, at specific sites using specified technologies. There are three major phases in the project. Phase I was undertaken in collaboration with the US Department of Energy. In this phase the teams jointly developed the conceptual approach and methodology and shared scientific information for application to a number of fuel cycles. On the European side work concentrated on the nuclear and coal fuel cycles which together were expected to raise many of the fundamental issues in fuel cycle analysis. The project is currently nearing completion of Phase 2. During this phase the methodology has been applied to a wide range of different fossil, nuclear and renewable fuel cycles for power generation and energy conservation options. Also a series of National Implementation Programmes are underway in which the methodology and accounting framework are being applied to reference sites throughout Europe. In addition the general methodology is being extended to address the evaluation of externalities associated with

  15. Multi-Unit Initiating Event Analysis for a Single-Unit Internal Events Level 1 PSA

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Dong San; Park, Jin Hee; Lim, Ho Gon [KAERI, Daejeon (Korea, Republic of)

    2016-05-15

    The Fukushima nuclear accident in 2011 highlighted the importance of considering the risks from multi-unit accidents at a site. The ASME/ANS probabilistic risk assessment (PRA) standard also includes some requirements related to multi-unit aspects, one of which (IE-B5) is as follows: 'For multi-unit sites with shared systems, DO NOT SUBSUME multi-unit initiating events if they impact mitigation capability [1].' However, the existing single-unit PSA models do not explicitly consider multi-unit initiating events and hence systems shared by multiple units (e.g., alternate AC diesel generator) are fully credited for the single unit and ignores the need for the shared systems by other units at the same site [2]. This paper describes the results of the multi-unit initiating event (IE) analysis performed as a part of the at-power internal events Level 1 probabilistic safety assessment (PSA) for an OPR1000 single unit ('reference unit'). In this study, a multi-unit initiating event analysis for a single-unit PSA was performed, and using the results, dual-unit LOOP initiating event was added to the existing PSA model for the reference unit (OPR1000 type). Event trees were developed for dual-unit LOOP and dual-unit SBO which can be transferred from dual- unit LOOP. Moreover, CCF basic events for 5 diesel generators were modelled. In case of simultaneous SBO occurrences in both units, this study compared two different assumptions on the availability of the AAC D/G. As a result, when dual-unit LOOP initiating event was added to the existing single-unit PSA model, the total CDF increased by 1∼ 2% depending on the probability that the AAC D/G is available to a specific unit in case of simultaneous SBO in both units.

  16. AN EMPIRICAL ANALYSIS OF THE INFLUENCE OF RISK FACTORS ON THE FREQUENCY AND IMPACT OF SEVERE EVENTS ON THE SUPPLY CHAIN IN THE CZECH REPUBLIC

    Directory of Open Access Journals (Sweden)

    José María Caridad

    2014-12-01

    Full Text Available Purpose: This paper is focused on an analysis and evaluation of severe events according to their frequency of occurrence and their impact on the company's manufacturing and distribution supply chains performance in the Czech Republic. Risk factors are introduced for critical events.Design/methodology: An identification and classification of severe events are realized on the basis of median mapping and mapping of ordinal variability acquired through the questionnaire survey of 82 companies. Analysis of 46 risk factors was sorted into 5 groups. We used asymmetric Somers's d statistics for testing the dependence of frequency and impact of a severe event on selected risk sources. The hierarchical cluster analysis is performed to identify relatively homogeneous groups of critical severe events according to their dependency on risk factors and its strength.Findings: Results showed that ‘a lack of contracts’ is considered to be the most critical severe event. Groups of demand and supply side and an external risk factor group were identified to be the most significant sources of risk factors. The worst cluster encompasses 11% of examined risk factors which should be prevented. We concluded that organizations need to adopt appropriate precautions and risk management methods in logistics.Originality: In this paper, the methodology for severe events evaluation in supply chain is designed. This methodology involves assessing the critical factors which influence the critical events and which should be prevented.

  17. A multispacecraft event study of Pc5 ultralow-frequency waves in the magnetosphere and their external drivers

    International Nuclear Information System (INIS)

    Wang, Chih-Ping; Thorne, Richard; Liu, Terry Z.; Hartinger, Michael D.; Nagai, Tsugunobu

    2017-01-01

    We investigate a quiet time event of magnetospheric Pc5 ultralow-frequency (ULF) waves and their likely external drivers using multiple spacecraft observations. Enhancements of electric and magnetic field perturbations in two narrow frequency bands, 1.5–2 mHz and 3.5–4 mHz, were observed over a large radial distance range from r ~ 5 to 11 RE. During the first half of this event, perturbations were mainly observed in the transverse components and only in the 3.5–4 mHz band. In comparison, enhancements were stronger during the second half in both transverse and compressional components and in both frequency bands. No indication of field line resonances was found for these magnetic field perturbations. Perturbations in these two bands were also observed in the magnetosheath, but not in the solar wind dynamic pressure perturbations. For the first interval, good correlations between the flow perturbations in the magnetosphere and magnetosheath and an indirect signature for Kelvin-Helmholtz (K-H) vortices suggest K-H surface waves as the driver. For the second interval, good correlations are found between the magnetosheath dynamic pressure perturbations, magnetopause deformation, and magnetospheric waves, all in good correspondence to interplanetary magnetic field (IMF) discontinuities. The characteristics of these perturbations can be explained by being driven by foreshock perturbations resulting from these IMF discontinuities. This event shows that even during quiet periods, K-H-unstable magnetopause and ion foreshock perturbations can combine to create a highly dynamic magnetospheric ULF wave environment

  18. The ExternE project: methodology, objectives and limitations

    International Nuclear Information System (INIS)

    Rabl, A.; Spadaro, J.V.

    2002-01-01

    This paper presents a summary of recent studies on external costs of energy systems, in particular the ExternE (External Costs of Energy) Project of the European Commission. To evaluate the impact and damage cost of a pollutant, one needs to carry out an impact pathway analysis; this involves the calculation of increased pollutant concentrations in all affected regions due to an incremental emission (e.g. μg/m 3 of particles, using models of atmospheric dispersion and chemistry), followed by the calculation of physical impacts (e.g. number of cases of asthma due to these particles, using a dose-response function). The entire so-called fuel chain (or fuel cycle) is evaluated and compared on the basis of delivered end use energy. Even though the uncertainties are large, the results provide substantial evidence that the classical air pollutants (particles, NO x and SO x ) from the combustion of fossil fuels impose a heavy toll, in addition to the cost of global warming. The external costs are especially large for coal; even for 'good current technology' they may be comparable to the price of electricity. For natural gas the external costs are about a third to a half of coal. The external costs of nuclear are small compared to the price of electricity (at most a few %), and so are the external costs of most renewable energy systems. (authors)

  19. Development and evaluation of a computerbased instrument supporting event analysis in NPP. Final report

    International Nuclear Information System (INIS)

    Szameitat, S.

    2002-11-01

    Information technologies (IT) in safety management are seen as opportunity to control and reduce risks. The processing of safety-critical event information, a central function of safety management, could be more efficient using computers. But organization structures are different, the processes of experience transfer are complex and the opportunities of IT are broad. To implement a support system is to question about design criteria of computer support for an event-based safety management system (eSMS). Two studies were conducted. Study 1 compares the organizational, technical and legal conditions for Safety Management in the German Nuclear Industry and the Norwegian Offshore Industry. It could identify design criteria, which independent from the operator influence the eSMS. Study 2 compares the eSMS of different nuclear power plants analyzing the organization structures and processes. Those internal and external criteria have a significant influence on a efficient design of a system support for eSMS. The third study makes the options and impact of computer support on experience transfer in eSMS as subject of discussion. For this purpose a simulation environment has been created. Groups investigated typical event scenarios from a nuclear power plant for contributing factors. The communication medium has been manipulated (face-to-face versus computer-mediated). Results of 15 groups indicate, that the collection of event information was promoted by computer-mediated communication. This is the foundation of the identification of contributing factors. The depth of analysis has not been influenced. Computer mediation hampers the learning of facts. IT can support safety management effectively. (orig.) [de

  20. Internal Versus External DSLs for Trace Analysis: Extended Abstract

    Science.gov (United States)

    Barringer, Howard; Havelund, Klaus

    2011-01-01

    This tutorial explores the design and implementation issues arising in the development of domain-specific languages for trace analysis. It introduces the audience to the general concepts underlying such special-purpose languages building upon the authors' own experiences in developing both external domain specific languages and systems, such as EAGLE, HAWK, RULER and LOGSCOPE, and the more recent internal domain-specific language and system TRACECONTRACT within the SCALA language.

  1. System risk evolution analysis and risk critical event identification based on event sequence diagram

    International Nuclear Information System (INIS)

    Luo, Pengcheng; Hu, Yang

    2013-01-01

    During system operation, the environmental, operational and usage conditions are time-varying, which causes the fluctuations of the system state variables (SSVs). These fluctuations change the accidents’ probabilities and then result in the system risk evolution (SRE). This inherent relation makes it feasible to realize risk control by monitoring the SSVs in real time, herein, the quantitative analysis of SRE is essential. Besides, some events in the process of SRE are critical to system risk, because they act like the “demarcative points” of safety and accident, and this characteristic makes each of them a key point of risk control. Therefore, analysis of SRE and identification of risk critical events (RCEs) are remarkably meaningful to ensure the system to operate safely. In this context, an event sequence diagram (ESD) based method of SRE analysis and the related Monte Carlo solution are presented; RCE and risk sensitive variable (RSV) are defined, and the corresponding identification methods are also proposed. Finally, the proposed approaches are exemplified with an accident scenario of an aircraft getting into the icing region

  2. Development of Mitigation Strategy for Beyond Design Basis External Events for NRC Design Certification

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Dong Hak; Lee, Jae Jong; Kim, Myung Ki [KHNP Central Research Institute, Daejeon (Korea, Republic of)

    2013-10-15

    In this study, how to develop FLEX strategy for beyond-design-basis external events for U. S. NRC design certification is examined. The development method of FLEX strategy for U. S. NRC design certification is examined. The applicants should make unit-specific FLEX strategy and establish the minimum coping capabilities consistent with unit-specific evaluation of the potential impacts and responses to BDBEEs. NEI 12-06 outlines the process to define and deploy the diverse and flexible mitigation strategies(FLEX strategy) that will increase defense-in-depth for beyond-design-basis scenarios to address the extended loss of alternating current (ac) power (ELAP) and loss of normal access to the ultimate heat sink (LUHS) occurring simultaneously at all units on a site. The order (EA-12-049) is issued to all reactor licensees, including holders of active, Construction Permit (CP) holders, and Combined License (COL) holders. Applicants for the new reactor design certification should prepare and submit FLEX strategy for NRC staff's review. Site-specific data related with the new reactor can't be determined during the new reactor design certification applications so that the unit-specific FLEX strategy should be developed.

  3. Development of Mitigation Strategy for Beyond Design Basis External Events for NRC Design Certification

    International Nuclear Information System (INIS)

    Kim, Dong Hak; Lee, Jae Jong; Kim, Myung Ki

    2013-01-01

    In this study, how to develop FLEX strategy for beyond-design-basis external events for U. S. NRC design certification is examined. The development method of FLEX strategy for U. S. NRC design certification is examined. The applicants should make unit-specific FLEX strategy and establish the minimum coping capabilities consistent with unit-specific evaluation of the potential impacts and responses to BDBEEs. NEI 12-06 outlines the process to define and deploy the diverse and flexible mitigation strategies(FLEX strategy) that will increase defense-in-depth for beyond-design-basis scenarios to address the extended loss of alternating current (ac) power (ELAP) and loss of normal access to the ultimate heat sink (LUHS) occurring simultaneously at all units on a site. The order (EA-12-049) is issued to all reactor licensees, including holders of active, Construction Permit (CP) holders, and Combined License (COL) holders. Applicants for the new reactor design certification should prepare and submit FLEX strategy for NRC staff's review. Site-specific data related with the new reactor can't be determined during the new reactor design certification applications so that the unit-specific FLEX strategy should be developed

  4. Discrete event simulation versus conventional system reliability analysis approaches

    DEFF Research Database (Denmark)

    Kozine, Igor

    2010-01-01

    Discrete Event Simulation (DES) environments are rapidly developing and appear to be promising tools for building reliability and risk analysis models of safety-critical systems and human operators. If properly developed, they are an alternative to the conventional human reliability analysis models...... and systems analysis methods such as fault and event trees and Bayesian networks. As one part, the paper describes briefly the author’s experience in applying DES models to the analysis of safety-critical systems in different domains. The other part of the paper is devoted to comparing conventional approaches...

  5. Analysis of Paks NPP Personnel Activity during Safety Related Event Sequences

    International Nuclear Information System (INIS)

    Bareith, A.; Hollo, Elod; Karsa, Z.; Nagy, S.

    1998-01-01

    Within the AGNES Project (Advanced Generic and New Evaluation of Safety) the Level-1 PSA model of the Paks NPP Unit 3 was developed in form of a detailed event tree/fault tree structure (53 initiating events, 580 event sequences, 6300 basic events are involved). This model gives a good basis for quantitative evaluation of potential consequences of actually occurred safety-related events, i.e. for precursor event studies. To make these studies possible and efficient, the current qualitative event analysis practice should be reviewed and a new additional quantitative analysis procedure and system should be developed and applied. The present paper gives an overview of the method outlined for both qualitative and quantitative analyses of the operator crew activity during off-normal situations. First, the operator performance experienced during past operational events is discussed. Sources of raw information, the qualitative evaluation process, the follow-up actions, as well as the documentation requirements are described. Second, the general concept of the proposed precursor event analysis is described. Types of modeled interactions and the considered performance influences are presented. The quantification of the potential consequences of the identified precursor events is based on the task-oriented, Level-1 PSA model of the plant unit. A precursor analysis system covering the evaluation of operator activities is now under development. Preliminary results gained during a case study evaluation of a past historical event are presented. (authors)

  6. External cephalic version-related risks: a meta-analysis.

    Science.gov (United States)

    Grootscholten, Kim; Kok, Marjolein; Oei, S Guid; Mol, Ben W J; van der Post, Joris A

    2008-11-01

    To systematically review the literature on external cephalic version-related complications and to assess if the outcome of a version attempt is related to complications. In March 2007 we searched MEDLINE, EMBASE, and the Cochrane Central Register of Controlled Trials. Studies reporting on complications from an external cephalic version attempt for singleton breech pregnancies after 36 weeks of pregnancy were selected. We calculated odds ratios (ORs) from studies that reported both on complications as well as on the position of the fetus immediately after the procedure. We found 84 studies, reporting on 12,955 version attempts that reported on external cephalic version-related complications. The pooled complication rate was 6.1% (95% CI 4.7-7.8), 0.24% for serious complications (95% confidence interval [CI] 0.17-0.34) and 0.35% for emergency cesarean deliveries (95% CI 0.26-0.47). Complications were not related to external cephalic version outcome (OR 1.2 (95% CI 0.93-1.7). External cephalic version is a safe procedure. Complications are not related to the fetal position after external cephalic version.

  7. Failure Analysis of a Helicopter External Fuel-Tank Pylon

    Science.gov (United States)

    Newman, John A.; Piascik, Robert S.; Lindenberg, Richard A.

    2002-01-01

    An eight-inch-long (0.2 m) crack was found in an external fuel-tank pylon of a U.S. Coast Guard HH-60 helicopter. The damaged pylon was removed from service and destructively examined at NASA Langley Research Center (LaRC) to determine the cause of the crack. Results of the analysis revealed that crack initiation occurred at corrosion pits in a fastener hole and crack propagation was a result of cyclic loading.

  8. Species-specific control of external superoxide levels by the coral holobiont during a natural bleaching event

    Science.gov (United States)

    Diaz, Julia M.; Hansel, Colleen M.; Apprill, Amy; Brighi, Caterina; Zhang, Tong; Weber, Laura; McNally, Sean; Xun, Liping

    2016-12-01

    The reactive oxygen species superoxide (O2.-) is both beneficial and detrimental to life. Within corals, superoxide may contribute to pathogen resistance but also bleaching, the loss of essential algal symbionts. Yet, the role of superoxide in coral health and physiology is not completely understood owing to a lack of direct in situ observations. By conducting field measurements of superoxide produced by corals during a bleaching event, we show substantial species-specific variation in external superoxide levels, which reflect the balance of production and degradation processes. Extracellular superoxide concentrations are independent of light, algal symbiont abundance and bleaching status, but depend on coral species and bacterial community composition. Furthermore, coral-derived superoxide concentrations ranged from levels below bulk seawater up to ~120 nM, some of the highest superoxide concentrations observed in marine systems. Overall, these results unveil the ability of corals and/or their microbiomes to regulate superoxide in their immediate surroundings, which suggests species-specific roles of superoxide in coral health and physiology.

  9. Autonomy and coordination: Controlling external influences on decision making

    NARCIS (Netherlands)

    Vecht, B. van der; Dignum, F.; Meyer, J.J.C.

    2009-01-01

    In order to achieve optimal results, an agent's way of decision making might need to change according to the circumstances. One of the aspects an agent can adapt is the way it processes external events. Therewith it controls to what extend it is being influenced by external factors. We argue that

  10. Parallel processor for fast event analysis

    International Nuclear Information System (INIS)

    Hensley, D.C.

    1983-01-01

    Current maximum data rates from the Spin Spectrometer of approx. 5000 events/s (up to 1.3 MBytes/s) and minimum analysis requiring at least 3000 operations/event require a CPU cycle time near 70 ns. In order to achieve an effective cycle time of 70 ns, a parallel processing device is proposed where up to 4 independent processors will be implemented in parallel. The individual processors are designed around the Am2910 Microsequencer, the AM29116 μP, and the Am29517 Multiplier. Satellite histogramming in a mass memory system will be managed by a commercial 16-bit μP system

  11. Analysis of event-mode data with Interactive Data Language

    International Nuclear Information System (INIS)

    De Young, P.A.; Hilldore, B.B.; Kiessel, L.M.; Peaslee, G.F.

    2003-01-01

    We have developed an analysis package for event-mode data based on Interactive Data Language (IDL) from Research Systems Inc. This high-level language is high speed, array oriented, object oriented, and has extensive visual (multi-dimensional plotting) and mathematical functions. We have developed a general framework, written in IDL, for the analysis of a variety of experimental data that does not require significant customization for each analysis. Unlike many traditional analysis package, spectra and gates are applied after data are read and are easily changed as analysis proceeds without rereading the data. The events are not sequentially processed into predetermined arrays subject to predetermined gates

  12. Attack Graph Construction for Security Events Analysis

    Directory of Open Access Journals (Sweden)

    Andrey Alexeevich Chechulin

    2014-09-01

    Full Text Available The paper is devoted to investigation of the attack graphs construction and analysis task for a network security evaluation and real-time security event processing. Main object of this research is the attack modeling process. The paper contains the description of attack graphs building, modifying and analysis technique as well as overview of implemented prototype for network security analysis based on attack graph approach.

  13. Energy policy and externalities: the life cycle analysis approach

    International Nuclear Information System (INIS)

    Virdis, M.R.

    2002-01-01

    In the energy sector, getting the prices right is a prerequisite for market mechanisms to work effectively towards sustainable development. However, energy production and use creates 'costs' external to traditional accounting practices, such as damages to human health and the environment resulting from residual emissions or risks associated with dependence on foreign suppliers. Energy market prices do not fully reflect those external costs. For example, the costs of climate change are not internalized and, therefore, consumers do not get the right price signals leading them to make choices that are optimised from a societal viewpoint. Economic theory has developed approaches to assessing and internalizing external costs that can be applied to the energy sector and, in principle, provide means to quantify and integrate relevant information in a comprehensive framework. The tools developed for addressing these issues are generally aimed at monetary valuation of impacts and damages and integration of the valued 'external costs' in total cost of the product, e.g. electricity. The approach of Life Cycle Analysis (LCA) provides a conceptual framework for a detailed and comprehensive comparative evaluation of energy supply options. This paper offers a summary of the LCA methodology and an overview of some of its limitations. It then illustrates, through a few examples, how the methodology can be used to inform or correct policy making and to orient investment decisions. Difficulties and issues emerging at various stages in the application and use of LCA results are discussed, although in such a short note, it is impossible to address all issues related to LCA. Therefore, as part of the concluding section, some issues are left open - and areas in which further analytical work may be needed are described. (author)

  14. The External Cost Evaluation of the Nuclear Severe Accident Using CVM

    International Nuclear Information System (INIS)

    Lee, Yong Suk; Lee, Byung Chul

    2006-01-01

    The external cost of energy can be defined as 'the cost not included in the energy market price', such as air pollution, noise, etc. Within the evaluation of the external cost of nuclear energy, the estimation of the external cost of severe accident is one of the major topics to be addressed. For the evaluation of the external cost of severe accident, the effect of risk aversion of the public against the severe accident must be addressed, because people are more concerned about low probability - high consequence events than about high probability - low consequence events having the same mean damage. It is generally recognized that there is a discrepancy between the social acceptability of the risk and the average monetary value which corresponds in principle to the compensation of the consequences for each individual of the population affected by the accident. In this paper, the CVM (Contingent Valuation Method) is used to integrate the risk aversion in the external costs of nuclear severe accidents in Korea

  15. Equipment and physical plant changes in response to the Fukushima event

    International Nuclear Information System (INIS)

    Newman, G.

    2013-01-01

    The Fukushima event led the international nuclear industry and regulatory bodies to challenge the ability of existing nuclear power plants to prevent and mitigate the effects of a severe external event leading to a total loss of AC power and resultant loss of cooling. Canadian Nuclear Industry's immediate response was to provide a high level of assurance that the existing plant is in a high state of readiness to deal with design basis and beyond design basis events, verify the capability of the existing plant to deal with beyond design basis events (equipment, procedures, staff qualification, external support agreements, etc), verify capability to mitigate station black out events, verify capability to cope with internal and external floods and address vulnerabilities to seismically induced damage to mitigation equipment.

  16. Potential off-normal events and associated radiological source terms for the compact ignition tokamak: Fusion Safety Program

    International Nuclear Information System (INIS)

    Holland, D.F.; Lyon, R.E.

    1987-10-01

    The Compact Ignition Tokamak (CIT), the latest step in the United States program to develop the commercial application of fusion power, is designed as the first fusion device to achieve ignition conditions. It is to be constructed near Princeton, New Jersey on the site of the existing Tokamak Fusion Test Reactor (TFTR). To address the environmental impact and public safety concerns, a preliminary analysis was performed of potential off-normal radiological releases. Operational occurrences, natural phenomena, accidents with external origins, and accidents external to the PPPL site were considered as potential sources for off-normal events. Based on an initial screening, events were selected for preliminary analysis. Included in these events were tritium releases from the tritium delivery and recovery system, tritium releases from the torus, releases of activated nitrogen from the test cell or cryostat, seismic events, and shipping accidents. In each case, the design considerations related to the event were reviewed and the release scenarios discussed. Because of the complexity of some of the proposed safety systems, in some cases event trees were used to describe the accident scenarios. For each scenario, the probability was estimated as well as the release magnitude, isotope, chemical form, and release mode. 10 refs., 17 figs., 5 tabs

  17. Application and Use of PSA-based Event Analysis in Belgium

    International Nuclear Information System (INIS)

    Hulsmans, M.; De Gelder, P.

    2003-01-01

    The paper describes the experiences of the Belgian nuclear regulatory body AVN with the application and the use of the PSAEA guidelines (PSA-based Event Analysis). In 2000, risk-based precursor analysis has increasingly become a part of the AVN process of feedback of operating experience, and constitutes in fact the first PSA application for the Belgian plants. The PSAEA guidelines were established by a consultant in the framework of an international project. In a first stage, AVN applied the PSAEA guidelines to two test cases in order to explore the feasibility and the interest of this type of probabilistic precursor analysis. These pilot studies demonstrated the applicability of the PSAEA method in general, and its applicability to the computer models of the Belgian state-of-the- art PSAs in particular. They revealed insights regarding the event analysis methodology, the resulting event severity and the PSA model itself. The consideration of relevant what-if questions allowed to identify - and in some cases also to quantify - several potential safety issues for improvement. The internal evaluation of PSAEA was positive and AVN decided to routinely perform several PSAEA studies per year. During 2000, PSAEA has increasingly become a part of the AVN process of feedback of operating experience. The objectives of the AVN precursor program have been clearly stated. A first pragmatic set of screening rules for operational events has been drawn up and applied. Six more operational events have been analysed in detail (initiating events as well as condition events) and resulted in a wide spectrum of event severity. In addition to the particular conclusions for each event, relevant insights have been gained regarding for instance event modelling and the interpretation of results. Particular attention has been devoted to the form of the analysis report. After an initial presentation of some key concepts, the particular context of this program and of AVN's objectives, the

  18. Cointegration Analysis of the Economic Growth, Military Expenditure, and External Debt: Evidence from Pakistan

    Directory of Open Access Journals (Sweden)

    Khalid Zaman

    2012-06-01

    Full Text Available This paper attempts to examine the relationship between real military spending (RME, level of economic activity (RGNP, and real external debt (RED by using a Johansen multivariate cointegration framework. The analysis is carried out using time series data over 1980-2008 The study investigates the long-run effects and short-run dynamics of the effect of rise in RGNP and RME on RED Pakistan. The quantitative evidence shows that external debt is more elastic with respect to military expenditure in the long run, whereas, there has been insignificant effect in the short-run. In the long-run, 1.00% increase in military expenditure leads to an increase in external debt by almost 3.96%. On the other hand, 1.00% increases in economic growth decreases external debt by 2.13%. In the short run, 1.00% increase in economic growth reduces external debt by 2.90%. The results presented in this study reinforce the importance to government, academic, and policy makers.

  19. HiggsToFourLeptonsEV in the ATLAS EventView Analysis Framework

    CERN Document Server

    Lagouri, T; Del Peso, J

    2008-01-01

    ATLAS is one of the four experiments at the Large Hadron Collider (LHC) at CERN. This experiment has been designed to study a large range of physics topics, including searches for previously unobserved phenomena such as the Higgs Boson and super-symmetry. The physics analysis package HiggsToFourLeptonsEV for the Standard Model (SM) Higgs to four leptons channel with ATLAS is presented. The physics goal is to investigate with the ATLAS detector, the SM Higgs boson discovery potential through its observation in the four-lepton (electron and muon) final state. HiggsToFourLeptonsEV is based on the official ATLAS software ATHENA and the EventView (EV) analysis framework. EventView is a highly flexible and modular analysis framework in ATHENA and it is one of several analysis schemes for ATLAS physics user analysis. At the core of the EventView is the representative "view" of an event, which defines the contents of event data suitable for event-level physics analysis. The HiggsToFourLeptonsEV package, presented in ...

  20. Physics analysis of the gang partial rod drive event

    International Nuclear Information System (INIS)

    Boman, C.; Frost, R.L.

    1992-08-01

    During the routine positioning of partial-length control rods in Gang 3 on the afternoon of Monday, July 27, 1992, the partial-length rods continued to drive into the reactor even after the operator released the controlling toggle switch. In response to this occurrence, the Safety Analysis and Engineering Services Group (SAEG) requested that the Applied Physics Group (APG) analyze the gang partial rod drive event. Although similar accident scenarios were considered in analysis for Chapter 15 of the Safety Analysis Report (SAR), APG and SAEG conferred and agreed that this particular type of gang partial-length rod motion event was not included in the SAR. This report details this analysis

  1. Probabilistic analysis of canister inserts for spent nuclear fuel

    International Nuclear Information System (INIS)

    Dillstroem, Peter

    2005-10-01

    In this study, probabilistic analysis of canister inserts for spent nuclear fuel has been performed. The main conclusions are: 1. For the baseline case, the probability of failure is insignificant (∼ 2x10 -9 ). This is the case even though several conservative assumptions have been made both in underlying deterministic analysis and in the probabilistic analysis. 2. The initiation event dominates (over the local collapse event) when the external pressure is below the baseline case (p = 44 MPa). The local collapse event dominates when the external pressure is above the baseline case. 3. The local collapse event is strongly dependent of the assumed external pressure. 4. The analysis of collapse only considers the first local collapse event, total collapse of the insert will occur at a much higher pressure. 5. The resulting probabilities are more dependent on the assumption regarding the eccentricity of the cassette than the assumption regarding outer corner radius of the profiles for steel section cassette. The results indicate that the maximum allowed eccentricity should not be larger than 5 mm. 6. The probability of initiation of crack growth is calculated using a defect distribution where one assumes the existence of one crack-like defect. A simple scaling argument can be applied to consider the number of defects through the thickness

  2. Multistate event history analysis with frailty

    Directory of Open Access Journals (Sweden)

    Govert Bijwaard

    2014-05-01

    Full Text Available Background: In survival analysis a large literature using frailty models, or models with unobserved heterogeneity, exists. In the growing literature and modelling on multistate models, this issue is only in its infant phase. Ignoring frailty can, however, produce incorrect results. Objective: This paper presents how frailties can be incorporated into multistate models, with an emphasis on semi-Markov multistate models with a mixed proportional hazard structure. Methods: First, the aspects of frailty modeling in univariate (proportional hazard, Cox and multivariate event history models are addressed. The implications of choosing shared or correlated frailty is highlighted. The relevant differences with recurrent events data are covered next. Multistate models are event history models that can have both multivariate and recurrent events. Incorporating frailty in multistate models, therefore, brings all the previously addressed issues together. Assuming a discrete frailty distribution allows for a very general correlation structure among the transition hazards in a multistate model. Although some estimation procedures are covered the emphasis is on conceptual issues. Results: The importance of multistate frailty modeling is illustrated with data on labour market and migration dynamics of recent immigrants to the Netherlands.

  3. External legitimation in international new ventures

    DEFF Research Database (Denmark)

    Turcan, Romeo V.

    2012-01-01

    This paper explores within the framework of new venture legitimation how and why international new ventures acquire external legitimacy and strive for survival in the face of critical events. Following a longitudinal multiple-case study methodology that was adopted for the purpose of theory...... building, the paper introduces the typology of captivity, and the four types that have emerged: captive industry supplier, captive dyadic partner, captive market leader, and free market leader. The effects of captivity types on the acquisition of external legitimacy and its survival, on reaching legitimacy...

  4. Probabilistic analysis of extreme wind events

    Energy Technology Data Exchange (ETDEWEB)

    Chaviaropoulos, P.K. [Center for Renewable Energy Sources (CRES), Pikermi Attikis (Greece)

    1997-12-31

    A vital task in wind engineering and meterology is to understand, measure, analyse and forecast extreme wind conditions, due to their significant effects on human activities and installations like buildings, bridges or wind turbines. The latest version of the IEC standard (1996) pays particular attention to the extreme wind events that have to be taken into account when designing or certifying a wind generator. Actually, the extreme wind events within a 50 year period are those which determine the ``static`` design of most of the wind turbine components. The extremes which are important for the safety of wind generators are those associated with the so-called ``survival wind speed``, the extreme operating gusts and the extreme wind direction changes. A probabilistic approach for the analysis of these events is proposed in this paper. Emphasis is put on establishing the relation between extreme values and physically meaningful ``site calibration`` parameters, like probability distribution of the annual wind speed, turbulence intensity and power spectra properties. (Author)

  5. Probabilistic safety analysis on an SBWR 72 hours after the initiating event

    International Nuclear Information System (INIS)

    Dominguez Bautista, M.T.; Peinador Veira, M.

    1996-01-01

    Passive plants, including SBWRs, are designed to carry out safety functions with passive systems during the first 72 hours after the initiation event with no need for manual actions or external support. After this period, some recovery actions are required to enable the passive systems to continue performing their safety functions. The study was carried out by the INITEC-Empresarios Agrupados Joint Venture within the framework of the international group collaborating with GE on this project. Its purpose has been to assess, by means of probabilistic criteria, the importance to safety of each of these support actions, in order to define possible requirements to be considered in the design in respect of said recovery actions. In brief, the methodology developed for this objective consists of (1) quantifying success event trees from the PSA up to 72 hours, (2) determining the actions required in each sequence to maintain Steady State after 72 hours, (3) identifying available alternative core cooling methods in each sequence, (4) establishing the approximate (order of magnitude) realizability of each alternative method, (5) calculating the frequency of core damage as a function of the failure probability of post-72-hour actions and (6) analysing the importance of post-72-hour actions. The results of this analysis permit the establishment, right from the conceptual design phase, of the requirements that will arise to ensure these actions in the long term, enhancing their reliability and preventing the accident from continuing beyond this period. (Author)

  6. Workshop on the use of PRA methodology for the analysis of reactor events and operational data: Proceedings

    International Nuclear Information System (INIS)

    Rasmuson, D.M.

    1992-06-01

    A workshop entitled ''The Use of PRA Methodology for the Analysis of Reactor Events and Operational Data'' was held on January 29--30, 1992 in Annapolis, Maryland. Over 50 participants from the NRC, its contractors, and others participated in the meetings. During the first day, presentations were made by invited speakers to discuss issues in relevant topics. On the second day, discussion groups were held to focus on three areas: risk significance of operational events, industry risk profile and generic concerns, and risk monitoring and risk-based performance indicators. Important considerations identified from the workshop are the following: Improve the Accident Sequence Precursor models and data. Improve the SCSS and NPRDS (e.g., by adding detailed performance information on selected components, by improving narratives on failure causes). Develop risk-based performance indicators. Use risk insights to help focus trending and performance analyses of components, systems, initiators, and sequences. Improve the statistical quality of trending and performance analyses. Flag implications of special conditions (e.g., external events, containment performance) during data studies. Trend common cause and human performance using appropriate models to obtain a better understanding of the impact and causes of failure. Develop a method for producing an industry risk profile

  7. Investigation of occurrences of loss of external power supply in Spanish nuclear power plants

    International Nuclear Information System (INIS)

    Conde, J.M.; Reig, J.

    1989-01-01

    The paper reports on an investigation undertaken by the Nuclear Safety Council into occurrences of loss of external power supply in Spanish light water plants between 1981 and 1987. During this period all of the plants investigated (nine), with the exception of one, experienced an event of this type. The causes, effects and duration of each are studied in detail and the conclusion is drawn that the main cause of this type of occurrence is the intrinsic instability of the Spanish national grid. The response of plants to these various failures in external power supply was studied, special attention being paid to the correct operation of safety systems. In addition, the behaviour of other systems not related to safety is discussed, as are modifications and actions taken as a result of accumulated experience with a view to improving the plant response in the event of the failure of the external power supply, and reducing the frequency of such occurrences and their effective duration. The data obtained from this analysis were compared with those obtained in studies performed in other countries and the conclusion was drawn that failures in the external power supply occur slightly more frequently in Spain than in other countries. Similarly, a comparison was drawn between plant response during an actual failure and the response obtained during loss of external power nuclear tests which are carried out in all Spanish plants during the startup (commissioning) programme, in order to ascertain whether the test itself is adequate. (author). 1 fig., 3 tabs

  8. Welding deformation analysis based on improved equivalent strain method to cover external constraint during cooling stage

    Directory of Open Access Journals (Sweden)

    Tae-Jun Kim

    2015-09-01

    Full Text Available In the present study, external restraints imposed normal to the plate during the cooling stage were determined to be effective for reduction of the angular distortion of butt-welded or fillet-welded plate. A welding analysis model under external force during the cooling stage was idealized as a prismatic member subjected to pure bending. The external restraint was represented by vertical force on both sides of the work piece and bending stress forms in the transverse direction. The additional bending stress distribution across the plate thickness was reflected in the improved inherent strain model, and a set of inherent strain charts with different levels of bending stress were newly calculated. From an elastic linear FE analysis using the inherent strain values taken from the chart and comparing them with those from a 3D thermal elasto-plastic FE analysis, welding deformation can be calculated.

  9. Emotional self-control and dysregulation: A dual-process analysis of pathways to externalizing/internalizing symptomatology and positive well-being in younger adolescents.

    Science.gov (United States)

    Wills, Thomas A; Simons, Jeffrey S; Sussman, Steve; Knight, Rebecca

    2016-06-01

    There is little knowledge about how emotional regulation contributes to vulnerability versus resilience to substance use disorder. With younger adolescents, we studied the pathways through which emotion regulation attributes are related to predisposing factors for disorder. A sample of 3561 adolescents (M age 12.5 years) was surveyed. Measures for emotional self-control (regulation of sadness and anger), emotional dysregulation (angerability, affective lability, and rumination about sadness or anger), and behavioral self-control (planfulness and problem solving) were obtained. A structural model was analyzed with regulation attributes related to six intermediate variables that are established risk or protective factors for adolescent substance use (e.g., academic involvement, stressful life events). Criterion variables were externalizing and internalizing symptomatology and positive well-being. Indirect pathways were found from emotional regulation to symptomatology through academic competence, stressful events, and deviance-prone attitudes and cognitions. Direct effects were also found: from emotional dysregulation to externalizing and internalizing symptomatology; emotional self-control to well-being; and behavioral self-control (inverse) to externalizing symptomatology. Emotional self-control and emotional dysregulation had independent effects and different types of pathways. Adolescents scoring high on emotional dysregulation are at risk for substance dependence because of more externalizing and internalizing symptomatology. Independently, youth with better behavioral and emotional self-control are at lower risk. This occurs partly through relations of regulation constructs to environmental variables that affect levels of symptomatology (e.g., stressful events, poor academic performance). Effects of emotion regulation were found at an early age, before the typical onset of substance disorder. Copyright © 2016 The Authors. Published by Elsevier Ireland Ltd

  10. INTERNAL HAZARDS ANALYSIS FOR LICENSE APPLICATION

    Energy Technology Data Exchange (ETDEWEB)

    R.J. Garrett

    2005-02-17

    The purpose of this internal hazards analysis is to identify and document the internal hazards and potential initiating events associated with preclosure operations of the repository at Yucca Mountain. Internal hazards are those hazards presented by the operation of the facility and by its associated processes that can potentially lead to a radioactive release or cause a radiological hazard. In contrast to external hazards, internal hazards do not involve natural phenomena and external man-made hazards. This internal hazards analysis was performed in support of the preclosure safety analysis and the License Application for the Yucca Mountain Project. The methodology for this analysis provides a systematic means to identify internal hazards and potential initiating events that may result in a radiological hazard or radiological release during the repository preclosure period. These hazards are documented in tables of potential internal hazards and potential initiating events (Section 6.6) for input to the repository event sequence categorization process. The results of this analysis will undergo further screening and analysis based on the criteria that apply to the performance of event sequence analyses for the repository preclosure period. The evolving design of the repository will be re-evaluated periodically to ensure that internal hazards that have not been previously evaluated are identified.

  11. INTERNAL HAZARDS ANALYSIS FOR LICENSE APPLICATION

    International Nuclear Information System (INIS)

    Garrett, R.J.

    2005-01-01

    The purpose of this internal hazards analysis is to identify and document the internal hazards and potential initiating events associated with preclosure operations of the repository at Yucca Mountain. Internal hazards are those hazards presented by the operation of the facility and by its associated processes that can potentially lead to a radioactive release or cause a radiological hazard. In contrast to external hazards, internal hazards do not involve natural phenomena and external man-made hazards. This internal hazards analysis was performed in support of the preclosure safety analysis and the License Application for the Yucca Mountain Project. The methodology for this analysis provides a systematic means to identify internal hazards and potential initiating events that may result in a radiological hazard or radiological release during the repository preclosure period. These hazards are documented in tables of potential internal hazards and potential initiating events (Section 6.6) for input to the repository event sequence categorization process. The results of this analysis will undergo further screening and analysis based on the criteria that apply to the performance of event sequence analyses for the repository preclosure period. The evolving design of the repository will be re-evaluated periodically to ensure that internal hazards that have not been previously evaluated are identified

  12. Integrated torrefaction vs. external torrefaction - A thermodynamic analysis for the case of a thermochemical biorefinery

    DEFF Research Database (Denmark)

    Clausen, Lasse Røngaard

    2014-01-01

    Integrated and external torrefaction is analyzed and compared via thermodynamic modeling. In this paper, integrated torrefaction is defined as torrefaction integrated with entrained flow gasification. External torrefaction is defined as the decentralized production of torrefied wood pellets...... and centralized conversion of the pellets by entrained flow gasification. First, the syngas production of the two methods was compared. Second, the two methods were compared by considering complete biorefineries with either integrated torrefaction or external torrefaction. The first part of the analysis showed...... from external torrefaction to integrated torrefaction. The costs of this increase in energy efficiency are as follows: 1) more difficult transport, storage and handling of the biomass feedstock (wood chips vs. torrefied wood pellets); 2) reduced plant size; 3) no net electricity production; and 4...

  13. Report 2: Guidance document on practices to model and implement external flooding hazards in extended PSA

    International Nuclear Information System (INIS)

    Rebour, V.; Georgescu, G.; Leteinturier, D.; Raimond, E.; La Rovere, S.; Bernadara, P.; Vasseur, D.; Brinkman, H.; Groudev, P.; Ivanov, I.; Turschmann, M.; Sperbeck, S.; Potempski, S.; Hirata, K.; Kumar, Manorma

    2016-01-01

    This report provides a review of existing practices to model and implement external flooding hazards in existing level 1 PSA. The objective is to identify good practices on the modelling of initiating events (internal and external hazards) with a perspective of development of extended PSA and implementation of external events modelling in extended L1 PSA, its limitations/difficulties as far as possible. The views presented in this report are based on the ASAMPSA-E partners' experience and available publications. The report includes discussions on the following issues: - how to structure a L1 PSA for external flooding events, - information needed from geosciences in terms of hazards modelling and to build relevant modelling for PSA, - how to define and model the impact of each flooding event on SSCs with distinction between the flooding protective structures and devices and the effect of protection failures on other SSCs, - how to identify and model the common cause failures in one reactor or between several reactors, - how to apply HRA methodology for external flooding events, - how to credit additional emergency response (post-Fukushima measures like mobile equipment), - how to address the specific issues of L2 PSA, - how to perform and present risk quantification. (authors)

  14. The Analysis of the Impact of Depreciation on External Debt in Long Run: Evidence From Croatia

    Directory of Open Access Journals (Sweden)

    Irena Palić

    2018-03-01

    Full Text Available The impact of exchange rate changes in small open economies has been a widely researched topic for decades. According to economic theory and relevant research, depreciation can have a positive impact on the economy through an increase in exports, and a negative effect through decrease in an individual consumption. The aim of this artcle is to assess the impact of exchange rate depreciation on external debt in Croatia in the long-run. The long-run impact of depreciation on external debt in Croatia is assessed using Johansen cointegration approach. The results point to the existence of one cointegration relation. The long-run impact of exchange rate depreciation on external debt in Croatia is statistically significant and positive, what is in line with previous research and economic theory. The conducted analysis outlines the possible negative impact of depreciation on Croatian economy through the increase of external indebtedness, what could consequently decrease the wealth of all sectors indebted in foreign currency. Since Croatia is a highly euroised small open economy with high external indebtedness in foreign currency, this research provides captivating results for monetary and fiscal policy-making in Croatia. Therefore, as a result of the conducted empirical analysis, the exchange rate depreciation in Croatia is not recommended as the instrument of increasing export competitiveness due to current high external indebtedness in foreign currency.

  15. Static Analysis for Event-Based XML Processing

    DEFF Research Database (Denmark)

    Møller, Anders

    2008-01-01

    Event-based processing of XML data - as exemplified by the popular SAX framework - is a powerful alternative to using W3C's DOM or similar tree-based APIs. The event-based approach is a streaming fashion with minimal memory consumption. This paper discusses challenges for creating program analyses...... for SAX applications. In particular, we consider the problem of statically guaranteeing the a given SAX program always produces only well-formed and valid XML output. We propose an analysis technique based on ecisting anglyses of Servlets, string operations, and XML graphs....

  16. The external costs of low probability-high consequence events: Ex ante damages and lay risks

    International Nuclear Information System (INIS)

    Krupnick, A.J.; Markandya, A.; Nickell, E.

    1994-01-01

    This paper provides an analytical basis for characterizing key differences between two perspectives on how to estimate the expected damages of low probability - high consequence events. One perspective is the conventional method used in the U.S.-EC fuel cycle reports [e.g., ORNL/RFF (1994a,b]. This paper articulates another perspective, using economic theory. The paper makes a strong case for considering this, approach as an alternative, or at least as a complement, to the conventional approach. This alternative approach is an important area for future research. I Interest has been growing worldwide in embedding the external costs of productive activities, particularly the fuel cycles resulting in electricity generation, into prices. In any attempt to internalize these costs, one must take into account explicitly the remote but real possibilities of accidents and the wide gap between lay perceptions and expert assessments of such risks. In our fuel cycle analyses, we estimate damages and benefits' by simply monetizing expected consequences, based on pollution dispersion models, exposure-response functions, and valuation functions. For accidents, such as mining and transportation accidents, natural gas pipeline accidents, and oil barge accidents, we use historical data to estimate the rates of these accidents. For extremely severe accidents--such as severe nuclear reactor accidents and catastrophic oil tanker spills--events are extremely rare and they do not offer a sufficient sample size to estimate their probabilities based on past occurrences. In those cases the conventional approach is to rely on expert judgments about both the probability of the consequences and their magnitude. As an example of standard practice, which we term here an expert expected damage (EED) approach to estimating damages, consider how evacuation costs are estimated in the nuclear fuel cycle report

  17. The external costs of low probability-high consequence events: Ex ante damages and lay risks

    Energy Technology Data Exchange (ETDEWEB)

    Krupnick, A J; Markandya, A; Nickell, E

    1994-07-01

    This paper provides an analytical basis for characterizing key differences between two perspectives on how to estimate the expected damages of low probability - high consequence events. One perspective is the conventional method used in the U.S.-EC fuel cycle reports [e.g., ORNL/RFF (1994a,b]. This paper articulates another perspective, using economic theory. The paper makes a strong case for considering this, approach as an alternative, or at least as a complement, to the conventional approach. This alternative approach is an important area for future research. I Interest has been growing worldwide in embedding the external costs of productive activities, particularly the fuel cycles resulting in electricity generation, into prices. In any attempt to internalize these costs, one must take into account explicitly the remote but real possibilities of accidents and the wide gap between lay perceptions and expert assessments of such risks. In our fuel cycle analyses, we estimate damages and benefits' by simply monetizing expected consequences, based on pollution dispersion models, exposure-response functions, and valuation functions. For accidents, such as mining and transportation accidents, natural gas pipeline accidents, and oil barge accidents, we use historical data to estimate the rates of these accidents. For extremely severe accidents--such as severe nuclear reactor accidents and catastrophic oil tanker spills--events are extremely rare and they do not offer a sufficient sample size to estimate their probabilities based on past occurrences. In those cases the conventional approach is to rely on expert judgments about both the probability of the consequences and their magnitude. As an example of standard practice, which we term here an expert expected damage (EED) approach to estimating damages, consider how evacuation costs are estimated in the nuclear fuel cycle report.

  18. [External therapy of plasma cell mastitis by jiuyi powder using partial least-squares discriminant analysis: a safety analysis].

    Science.gov (United States)

    Ye, Mei-na; Yang, Ming; Cheng, Yi-qin; Wang, Bing; Zhu, Ying; Xia, Ya-ru; Meng, Tian; Chen, Hao; Chen, Li-ying; Cheng, Hong-feng

    2015-04-01

    To evaluate the safety and the clinical value of external use of jiuyi Powder (JP) in treating plasma cell mastitis using partial least-squares discriminant analysis (PLSDA). Totally 50 patients with plasma cell mastitis treated by external use of JP were observed and biochemical examinations of blood and urine detected before application, at day 4 after application, at day 1 and 14 after discontinuation. Blood mercury and urinary mercury were detected before application, at day 1, 4, and 7 after application, at day 1 and 14 after discontinuation. Urinary mercury was also detected at 28 after discontinuation and 3 months after discontinuation. The information of wound, days of external application and the total dosage of external application were recorded before application, at day 1, 4, and 7 after application, as well as at day 1 after discontinuation. Then a discriminant model covering potential safety factors was set up by PLSDA after screening safety indices with important effects. The applicability of the model was assessed using area under ROC curve. Potential safety factors were assessed using variable importance in the projection (VIP). Urinary β2-microglobulin (β2-MG), urinary N-acetyl-β-D-glucosaminidase (NAG), 24 h urinary protein, and urinary α1-microglobulin (α1-MG) were greatly affected by external use of JP in treating plasma cell mastitis. The accuracy rate of PLSDA discriminate model was 74. 00%. The sensitivity, specificity, and the area under ROC curve was 0. 7826, 0. 7037, and 0. 8084, respectively. Three factors with greater effect on the potential safety were screened as follows: pre-application volume of the sore cavity, days of external application, and the total dosage of external application. PLSDA method could be used in analyzing bioinformation of clinical Chinese medicine. Urinary β2-MG and urinary NAG were two main safety monitoring indices. Days of external application and the total dosage of external application were main

  19. Hybrid instrument applied to human reliability study in event of loss of external electric power in a nuclear power plant; Instrumento hibrido aplicado ao estudo da confiabilidade humana em evento de perda de energia eletrica externa em usina nuclear

    Energy Technology Data Exchange (ETDEWEB)

    Martins, Eduardo Ferraz

    2015-04-01

    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. Patient safety in external beam radiotherapy, results of the ACCIRAD project: Current status of proactive risk assessment, reactive analysis of events, and reporting and learning systems in Europe.

    Science.gov (United States)

    Malicki, Julian; Bly, Ritva; Bulot, Mireille; Godet, Jean-Luc; Jahnen, Andreas; Krengli, Marco; Maingon, Philippe; Prieto Martin, Carlos; Przybylska, Kamila; Skrobała, Agnieszka; Valero, Marc; Jarvinen, Hannu

    2017-04-01

    To describe the current status of implementation of European directives for risk management in radiotherapy and to assess variability in risk management in the following areas: 1) in-country regulatory framework; 2) proactive risk assessment; (3) reactive analysis of events; and (4) reporting and learning systems. The original data were collected as part of the ACCIRAD project through two online surveys. Risk assessment criteria are closely associated with quality assurance programs. Only 9/32 responding countries (28%) with national regulations reported clear "requirements" for proactive risk assessment and/or reactive risk analysis, with wide variability in assessment methods. Reporting of adverse error events is mandatory in most (70%) but not all surveyed countries. Most European countries have taken steps to implement European directives designed to reduce the probability and magnitude of accidents in radiotherapy. Variability between countries is substantial in terms of legal frameworks, tools used to conduct proactive risk assessment and reactive analysis of events, and in the reporting and learning systems utilized. These findings underscore the need for greater harmonisation in common terminology, classification and reporting practices across Europe to improve patient safety and to enable more reliable inter-country comparisons. Copyright © 2017 Elsevier B.V. All rights reserved.

  1. 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)

  2. Cognitive-behavioral therapy for externalizing disorders: A meta-analysis of treatment effectiveness.

    Science.gov (United States)

    Battagliese, Gemma; Caccetta, Maria; Luppino, Olga Ines; Baglioni, Chiara; Cardi, Valentina; Mancini, Francesco; Buonanno, Carlo

    2015-12-01

    Externalizing disorders are the most common and persistent forms of maladjustment in childhood. The aim of this study was to conduct a meta-analysis evaluating the effectiveness of Cognitive Behavioral Therapy (CBT) to reduce externalizing symptoms in two disorders: Attention Deficit Hyperactivity Disorder (ADHD) and Oppositive Defiant Disorder (ODD). The efficacy of CBT to improve social competence and positive parenting and reduce internalizing behaviors, parent stress and maternal depression was also explored. The database PsycInfo, PsycARTICLES, Medline and PubMed were searched to identify relevant studies. Twenty-one trials met the inclusion criteria. Results showed that the biggest improvement, after CBT, was in ODD symptoms (-0.879) followed by parental stress (-0.607), externalizing symptoms (-0.52), parenting skills (-0.381), social competence (-0.390) and ADHD symptoms (-0.343). CBT was also associated with improved attention (-0.378), aggressive behaviors (-0.284), internalizing symptoms (-0.272) and maternal depressive symptoms (-0.231). Overall, CBT is an effective treatment option for externalizing disorders and is also associated with reduced parental distress and maternal depressive symptoms. Multimodal treatments targeting both children and caregivers' symptoms (e.g. maternal depressive symptoms) appear important to produce sustained and generalized benefits. Copyright © 2015 Elsevier Ltd. All rights reserved.

  3. Event Shape Analysis in ALICE

    CERN Document Server

    AUTHOR|(CDS)2073367; Paic, Guy

    2009-01-01

    The jets are the final state manifestation of the hard parton scattering. Since at LHC energies the production of hard processes in proton-proton collisions will be copious and varied, it is important to develop methods to identify them through the study of their final states. In the present work we describe a method based on the use of some shape variables to discriminate events according their topologies. A very attractive feature of this analysis is the possibility of using the tracking information of the TPC+ITS in order to identify specific events like jets. Through the correlation between the quantities: thrust and recoil, calculated in minimum bias simulations of proton-proton collisions at 10 TeV, we show the sensitivity of the method to select specific topologies and high multiplicity. The presented results were obtained both at level generator and after reconstruction. It remains that with any kind of jet reconstruction algorithm one will confronted in general with overlapping jets. The present meth...

  4. [Analysis of the results of the SEIMC External Quality Control Program. Year 2013].

    Science.gov (United States)

    de Gopegui Bordes, Enrique Ruiz; Orta Mira, Nieves; Del Remedio Guna Serrano, M; Medina González, Rafael; Rosario Ovies, María; Poveda, Marta; Gimeno Cardona, Concepción

    2015-07-01

    The External Quality Control Program of the Spanish Society of Infectious Diseases and Clinical Microbiology (SEIMC) include controls for bacteriology, serology, mycology, parasitology, mycobacteria, virology, molecular microbiology and HIV-1, HCV and HBV viral loads. This manuscript presents the analysis of results obtained of the participants from the 2013 SEIMC External Quality Control Programme, except viral loads controls, that they are summarized in a manuscript abroad. As a whole, the results obtained in 2013 confirm the excellent skill and good technical standards found in previous editions. However, erroneous results can be obtained in any laboratory and in clinically relevant determinations. Once again, the results of this program highlighted the need to implement both internal and external controls in order to assure the maximal quality of the microbiological tests. Copyright © 2015 Elsevier España, S.L.U. All rights reserved.

  5. MCNP simulation of the influence of the external moisture on low calorific value in the coal quality analysis by neutron

    International Nuclear Information System (INIS)

    Liu Dekun; Zhang Hongyu; Zhang Lihong; Dong Huan; Gu Deshan

    2012-01-01

    An important index in assessment of coal quality is low calorific value. Using neutron to analysis coal quality, the more the coal moisture content, especially the increasing of external moisture will reduce the low calorific value. The principle of coal quality analysis by neutron prompt Gamma-ray is introduced. The influence of the gamma count of the carbon element peak with increasing external moisture in coal samples was simulated using MCNP code. And discussed the reasons how external moisture content influence the calorific value. Simulation results indicate that with the increasing of external moisture in the coal samples, the gamma count of the carbon element peak dwindling, and the low calorific value reducing. The conclusion is : using neutrons method to analysis coal quality, the more external moisture content, the larger error of the measurement results of the carbon element, and will influence the calculation accuracy of the low calorific value. (authors)

  6. Probabilistic analysis of canister inserts for spent nuclear fuel

    Energy Technology Data Exchange (ETDEWEB)

    Dillstroem, Peter [Det Norske Veritas, Stockholm (Sweden)

    2005-10-01

    In this study, probabilistic analysis of canister inserts for spent nuclear fuel has been performed. The main conclusions are: 1. For the baseline case, the probability of failure is insignificant ({approx} 2x10{sup -9}). This is the case even though several conservative assumptions have been made both in underlying deterministic analysis and in the probabilistic analysis. 2. The initiation event dominates (over the local collapse event) when the external pressure is below the baseline case (p = 44 MPa). The local collapse event dominates when the external pressure is above the baseline case. 3. The local collapse event is strongly dependent of the assumed external pressure. 4. The analysis of collapse only considers the first local collapse event, total collapse of the insert will occur at a much higher pressure. 5. The resulting probabilities are more dependent on the assumption regarding the eccentricity of the cassette than the assumption regarding outer corner radius of the profiles for steel section cassette. The results indicate that the maximum allowed eccentricity should not be larger than 5 mm. 6. The probability of initiation of crack growth is calculated using a defect distribution where one assumes the existence of one crack-like defect. A simple scaling argument can be applied to consider the number of defects through the thickness.

  7. Methodology for Selecting Initiating Events and Hazards for Consideration in an Extended PSA

    International Nuclear Information System (INIS)

    Wielenberg, A.; Hage, M.; Loeffler, H.; Alzbutas, R.; Apostol, M.; Bareith, A.; Siklossy, T.; Brac, P.; Burgazzi, L.; Cazzoli, E.; Vitazkova, J.; Cizelj, L.; Prosek, A.; Volkanovski, A.; Hashimoto, K.; Godefroy, F.; Gonzalez, M.; Groudev, P.; Kolar, L.; Kumar, M.; Nitoi, M.; Raimond, E.

    2016-01-01

    An extended PSA applies to a site of one or several Nuclear Power Plant unit(s) and its environment. It intends to calculate the risk induced by the main sources of radioactivity (reactor core and spent fuel storages) on the site, taking into account all operating states for each main source and all possible relevant accident initiating events (both internal and external) affecting one unit or the whole site. The combination between hazards or initiating events and their impact on a unit or the whole site is a crucial issue for an extended PSA. The report tries to discuss relevant methodologies for this purpose. The report proposes a methodology to select initiating events and hazards for the development of an extended PSA. The proposed methodology for initiating events identification, screening and bounding analysis for an extended PSA consists of four major steps: 1. A comprehensive identification of events and hazards and their respective combinations applicable to the plant and site. Qualitative screening criteria will be applied, 2. The calculation of initial (possibly conservative) frequency claims for events and hazards and their respective combinations applicable to the plant and the site. Quantitative screening criteria will be applied, 3. An impact analysis and bounding assessment for all applicable events and scenarios. Events are either screened out from further more detailed analysis, or are assigned to a bounding event (group), or are retained for detailed analysis, 4. The probabilistic analysis of all retained (bounding) events at the appropriate level of detail. (authors)

  8. 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

  9. Analysis of system and of course of events

    International Nuclear Information System (INIS)

    Hoertner, H.; Kersting, E.J.; Puetter, B.M.

    1986-01-01

    The analysis of the system and of the course of events is used to determine the frequency of core melt-out accidents and to describe the safety-related boundary conditions of appropriate accidents. The lecture is concerned with the effect of system changes in the reference plant and the effect of triggering events not assessed in detail or not sufficiently assessed in detail in phase A of the German Risk Study on the frequency of core melt-out accidents, the minimum requirements for system functions for controlling triggering events, i.e. to prevent core melt-out accidents, the reliability data important for reliability investigations and frequency assessments. (orig./DG) [de

  10. ANALYSIS OF INPATIENT HOSPITAL STAFF MENTAL WORKLOAD BY MEANS OF DISCRETE-EVENT SIMULATION

    Science.gov (United States)

    2016-03-24

    ANALYSIS OF INPATIENT HOSPITAL STAFF MENTAL WORKLOAD BY MEANS OF DISCRETE -EVENT SIMULATION...in the United States. AFIT-ENV-MS-16-M-166 ANALYSIS OF INPATIENT HOSPITAL STAFF MENTAL WORKLOAD BY MEANS OF DISCRETE -EVENT SIMULATION...UNLIMITED. AFIT-ENV-MS-16-M-166 ANALYSIS OF INPATIENT HOSPITAL STAFF MENTAL WORKLOAD BY MEANS OF DISCRETE -EVENT SIMULATION Erich W

  11. Mode of delivery after successful external cephalic version: a systematic review and meta-analysis.

    Science.gov (United States)

    de Hundt, Marcella; Velzel, Joost; de Groot, Christianne J; Mol, Ben W; Kok, Marjolein

    2014-06-01

    To assess the mode of delivery in women after a successful external cephalic version by performing a systematic review and meta-analysis. We searched MEDLINE, Embase, ClinicalTrials.gov, Cumulative Index to Nursing and Allied Health Literature, and the Cochrane Library for studies reporting on the mode of delivery in women after successful external cephalic version at term and women with a spontaneous cephalic-presenting fetus. Two reviewers independently selected studies, extracted data, and assessed study quality. The association between mode of delivery and successful external cephalic version was expressed as a common odds ratio with a 95% confidence interval (CI). We identified three cohort studies and eight case-control studies, reporting on 46,641 women. The average cesarean delivery rate for women with a successful external cephalic version was 21%. Women after successful external cephalic version were at increased risk for cesarean delivery for dystocia (odds ratio [OR] 2.2, 95% CI 1.6-3.0), cesarean delivery for fetal distress (OR 2.2, 95% CI 1.6-2.9), and instrumental vaginal delivery (OR 1.4, 95% CI 1.1-1.7). Women who have had a successful external cephalic version for breech presentation are at increased risk for cesarean delivery and instrumental vaginal delivery as compared with women with a spontaneous cephalic presentation. Nevertheless, with a number needed to treat of three, external cephalic version still remains a very efficient procedure to prevent a cesarean delivery.

  12. External Determinants of the Development of Small and Medium-Sized Enterprises – Empirical Analysis

    Directory of Open Access Journals (Sweden)

    Renata Lisowska

    2015-01-01

    Full Text Available The paper aims to identify external determinants of the development of small and medium-sized enterprises and assess their impact on the functioning of these entities in Poland. Meeting this objective required: identifying determinants of the development of SMEs, determining the current development situation of the surveyed enterprises and examining the impact of external determinants on the development of SMEs. The implementation of the above-presented goals was based on the following assumptions: (i the current situation of the surveyed enterprises is determined with the use of quantitative indicators (turnover volume, number of employees, market share, profit levels (ii the analysis of external determinants encompasses three components of the environment: the macro-environment, the meso-environment and the micro-environment, (iii in each analysed area there are separate analyses conducted for micro, small and medium-sized enterprises, enabling greater precision in the identification of external determinants of development for each category of businesses.

  13. Acute cardiac events and deployment of emergency medical teams and automated external defibrillators in large football stadiums in the Netherlands.

    Science.gov (United States)

    van de Sandt, Femke; Umans, Victor

    2009-10-01

    The incidence of acute cardiac events - including out-of-hospital cardiac arrest - may be increased in visitors of large sports stadiums when compared with the general population. This study sought to investigate the incidence of acute cardiac events inside large Dutch football stadiums, as well as the emergency response systems deployed in these stadiums and the success rate for in-stadium resuscitation. Retrospective cohort study using a questionnaire sent to the 20 Dutch stadiums that hosted professional matches during the 2006-2007 and 2007-2008 football seasons. Stadium capacity ranged from 3600 to 51 600 spectators. Nearly 13 million spectators attended 686 'Eredivisie' (Honorary Division) and European football matches. All stadiums distribute multiple emergency medical teams among the spectators. Eighty-five percent of the stadiums have an ambulance standby during matches, 95% of the stadiums were equipped with automated external defibrillators (AEDs) during the study period. On an average, one AED was available for every 7576 spectators (range 1800-29 600). Ninety-three cardiac events were reported (7.3 per 1 million spectators). An AED was used 22 times (1.7 per 1 million spectators). Resuscitation was successful in 18 cases (82%, 95% confidence interval: 61-93). The incidence of out-of-hospital cardiac arrest inside large football stadiums in the Netherlands, albeit increased when compared with the general population, is low. The success rate for in-stadium resuscitation by medical teams equipped with AEDs is high. Dutch stadiums appear vigilant in regard to acute cardiac events. This report highlights the importance of adequate emergency medical response systems (including AEDs) in large sports venues.

  14. List of external hazards to be considered in ASAMPSA-E

    International Nuclear Information System (INIS)

    Decker, Kurt; Brinkman, Hans

    2016-01-01

    The current report includes an exhaustive list of external hazards posing potential threats to nuclear installations. The list comprises of both, natural and man-made external hazards. Also, a cross correlation matrix of the hazards is presented. The list is the starting point for the hazard analysis process in Level 1 PSA as outlined by IAEA (2010; SSG-3) and the definition of design basis as required by WENRA (2014; Reference Levels for Existing Reactors). The list is regarded comprehensive by including all types of hazards that were previously cited in documents by IAEA and WENRA-RHWG. 73 natural hazards (N1 to N73) and 24 man-made external hazards (M1 to M24) are included. Natural hazards are grouped into seismo-tectonic hazards, flooding and hydrological hazards, extreme values of meteorological phenomena, rare meteorological phenomena, biological hazards / infestation, geological hazards, and forest fire. The list of external man-made hazards includes industry accidents, military accidents, transportation accidents, pipeline accidents and other man-made external events. The dataset further contains information on hazard correlations. 577 correlations between individual hazards are identified and shown in a cross-correlation chart. Correlations discriminate between: (1) Causally connected hazards (cause-effect relation) where one hazard (e.g., liquefaction) may be caused by another hazard (e.g., earthquake); or where one hazard (e.g., high wind) is a prerequisite for a correlated hazard (e.g., storm surge). (authors)

  15. Integrated torrefaction vs. external torrefaction – A thermodynamic analysis for the case of a thermochemical biorefinery

    International Nuclear Information System (INIS)

    Clausen, Lasse R.

    2014-01-01

    Integrated and external torrefaction is analyzed and compared via thermodynamic modeling. In this paper, integrated torrefaction is defined as torrefaction integrated with entrained flow gasification. External torrefaction is defined as the decentralized production of torrefied wood pellets and centralized conversion of the pellets by entrained flow gasification. First, the syngas production of the two methods was compared. Second, the two methods were compared by considering complete biorefineries with either integrated torrefaction or external torrefaction. The first part of the analysis showed that the biomass to syngas efficiency can be increased from 63% to 86% (LHV-dry) when switching from external torrefaction to integrated torrefaction. The second part of the analysis showed that the total energy efficiency (biomass to methanol + net electricity) could be increased from 53% to 63% when switching from external torrefaction to integrated torrefaction. The costs of this increase in energy efficiency are as follows: 1) more difficult transport, storage and handling of the biomass feedstock (wood chips vs. torrefied wood pellets); 2) reduced plant size; 3) no net electricity production; and 4) a more complex plant design. - Highlights: • Integrated torrefaction is compared with external torrefaction. • Biomass to syngas energy efficiencies of 63–86% are achieved. • Two thermochemical biorefinery are designed and analysed by thermodynamic modeling. • Biomass to fuel + electricity energy efficiencies of 53–63% are achieved. • The pros and cons of integrated torrefaction are described

  16. External costs of electricity; Les couts externes de l'electricite

    Energy Technology Data Exchange (ETDEWEB)

    Rabl, A. [Ecole des Mines de Paris, 75 (France); Spadaro, J.V. [International Atomic Energy Agency (IAEA), Vienna (Austria)

    2005-07-01

    This article presents a synthesis of the ExternE project (External costs of Energy) of the European community about the external costs of power generation. Pollution impacts are calculated using an 'impact pathways' analysis, i.e. an analysis of the emission - dispersion - dose-response function - cost evaluation chain. Results are presented for different fuel cycles (with several technological variants) with their confidence intervals. The environmental impact costs are particularly high for coal: for instance, in France, for coal-fired power plants it is of the same order as the electricity retail price. For natural gas, this cost is about a third of the one for coal. On the contrary, the environmental impact costs for nuclear and renewable energies are low, typically of few per cent of the electricity price. The main part of these costs corresponds to the sanitary impacts, in particular the untimely mortality. In order to avoid any controversy about the cost evaluation of mortality, the reduction of the expectation of life due to the different fuel cycles is also indicated and the risks linked with nuclear energy are presented using several comparisons. (J.S.)

  17. Analysis of catchments response to severe drought event for ...

    African Journals Online (AJOL)

    Nafiisah

    The run sum analysis method was a sound method which indicates in ... intensity and duration of stream flow depletion between nearby catchments. ... threshold level analysis method, and allows drought events to be described in more.

  18. Breath analysis using external cavity diode lasers: a review

    Science.gov (United States)

    Bayrakli, Ismail

    2017-04-01

    Most techniques that are used for diagnosis and therapy of diseases are invasive. Reliable noninvasive methods are always needed for the comfort of patients. Owing to its noninvasiveness, ease of use, and easy repeatability, exhaled breath analysis is a very good candidate for this purpose. Breath analysis can be performed using different techniques, such as gas chromatography mass spectrometry (MS), proton transfer reaction-MS, and selected ion flow tube-MS. However, these devices are bulky and require complicated procedures for sample collection and preconcentration. Therefore, these are not practical for routine applications in hospitals. Laser-based techniques with small size, robustness, low cost, low response time, accuracy, precision, high sensitivity, selectivity, low detection limit, real-time, and point-of-care detection have a great potential for routine use in hospitals. In this review paper, the recent advances in the fields of external cavity lasers and breath analysis for detection of diseases are presented.

  19. Associations of parenting dimensions and styles with externalizing problems of children and adolescents: An updated meta-analysis.

    Science.gov (United States)

    Pinquart, Martin

    2017-05-01

    The present meta-analysis integrates research from 1,435 studies on associations of parenting dimensions and styles with externalizing symptoms in children and adolescents. Parental warmth, behavioral control, autonomy granting, and an authoritative parenting style showed very small to small negative concurrent and longitudinal associations with externalizing problems. In contrast, harsh control, psychological control, authoritarian, permissive, and neglectful parenting were associated with higher levels of externalizing problems. The strongest associations were observed for harsh control and psychological control. Parental warmth, behavioral control, harsh control, psychological control, autonomy granting, authoritative, and permissive parenting predicted change in externalizing problems over time, with associations of externalizing problems with warmth, behavioral control, harsh control, psychological control, and authoritative parenting being bidirectional. Moderating effects of sampling, child's age, form of externalizing problems, rater of parenting and externalizing problems, quality of measures, and publication status were identified. Implications for future research and practice are discussed. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

  20. Event history analysis and the cross-section

    DEFF Research Database (Denmark)

    Keiding, Niels

    2006-01-01

    Examples are given of problems in event history analysis, where several time origins (generating calendar time, age, disease duration, time on study, etc.) are considered simultaneously. The focus is on complex sampling patterns generated around a cross-section. A basic tool is the Lexis diagram....

  1. Human performance analysis of industrial radiography radiation exposure events

    International Nuclear Information System (INIS)

    Reece, W.J.; Hill, S.G.

    1995-01-01

    A set of radiation overexposure event reports were reviewed as part of a program to examine human performance in industrial radiography for the US Nuclear Regulatory Commission. Incident records for a seven year period were retrieved from an event database. Ninety-five exposure events were initially categorized and sorted for further analysis. Descriptive models were applied to a subset of severe overexposure events. Modeling included: (1) operational sequence tables to outline the key human actions and interactions with equipment, (2) human reliability event trees, (3) an application of an information processing failures model, and (4) an extrapolated use of the error influences and effects diagram. Results of the modeling analyses provided insights into the industrial radiography task and suggested areas for further action and study to decrease overexposures

  2. Separate storage of pulser events

    International Nuclear Information System (INIS)

    Goerner, W.

    1978-01-01

    External pulser events were directed to a memory section apart from the spectrum, thus subtracting the background with its statistics from the pulser peak and allowing small pulser rates to be used. (author)

  3. 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

  4. Analysis of event tree with imprecise inputs by fuzzy set theory

    International Nuclear Information System (INIS)

    Ahn, Kwang Il; Chun, Moon Hyun

    1990-01-01

    Fuzzy set theory approach is proposed as a method to analyze event trees with imprecise or linguistic input variables such as 'likely' or 'improbable' instead of the numerical probability. In this paper, it is shown how the fuzzy set theory can be applied to the event tree analysis. The result of this study shows that the fuzzy set theory approach can be applied as an acceptable and effective tool for analysis of the event tree with fuzzy type of inputs. Comparisons of the fuzzy theory approach with the probabilistic approach of computing probabilities of final states of the event tree through subjective weighting factors and LHS technique show that the two approaches have common factors and give reasonable results

  5. Historical estimates of external gamma exposure and collective external gamma exposure from testing at the Nevada Test Site. I. Test series through HARDTACK II, 1958

    International Nuclear Information System (INIS)

    Anspaugh, L.R.; Church, B.W.

    1986-01-01

    In 1959, the Test Manager's Committee to Establish Fallout Doses calculated estimated external gamma exposure at populated locations based upon measurements of external gamma-exposure rate. Using these calculations and estimates of population, we have tabulated the collective estimated external gamma exposures for communities within established fallout patterns. The total collective estimated external gamma exposure is 85,000 person-R. The greatest collective exposures occurred in three general areas: Saint George, UT; Ely, NV; and Las Vegas, NV. Three events, HARRY (19 May 1953), BEE (22 March 1955), and SMOKY (31 August 1957), accounted for more than half the total collective estimated external gamma exposure. The bases of the calculational models for external gamma exposure of infinite exposure, estimated exposure, and 1-yr effective biological exposure are explained

  6. Historical estimates of external gamma exposure and collective external gamma exposure from testing at the Nevada Test Site. I. Test series through HARDTACK II, 1958

    International Nuclear Information System (INIS)

    Anspaugh, L.R.; Church, B.W.

    1985-12-01

    In 1959, the Test Manager's Committee to Establish Fallout Doses calculated estimated external gamma exposure at populated locations based upon measurements of external gamma-exposure rate. Using these calculations and estimates of population, we have tabulated the collective estimated external gamma exposures for communities within established fallout patterns. The total collective estimated external gamma exposure is 85,000 person-R. The greatest collective exposures occurred in three general areas: Saint George, Utah; Ely, Nevada; and Las Vegas, Nevada. Three events, HARRY (May 19, 1953), BEE (March 22, 1955), and SMOKY (August 31, 1957), accounted for over half of the total collective estimated external gamma exposure. The bases of the calculational models for external gamma exposure of ''infinite exposure,'' ''estimated exposure,'' and ''one year effective biological exposure'' are explained. 4 figs., 7 tabs

  7. Anticipated Intraoperative Electron Beam Boost, External Beam Radiation Therapy, and Limb-Sparing Surgical Resection for Patients with Pediatric Soft-Tissue Sarcomas of the Extremity: A Multicentric Pooled Analysis of Long-Term Outcomes

    Energy Technology Data Exchange (ETDEWEB)

    Sole, Claudio V., E-mail: cvsole@uc.cl [Department of Oncology, Hospital General Universitario Gregorio Marañón, Madrid (Spain); School of Medicine, Complutense University, Madrid (Spain); Service of Radiation Oncology, Instituto de Radiomedicina, Santiago (Chile); Calvo, Felipe A. [Department of Oncology, Hospital General Universitario Gregorio Marañón, Madrid (Spain); School of Medicine, Complutense University, Madrid (Spain); Polo, Alfredo [Service of Radiation Oncology, Hospital Universitario Ramón y Cajal, Madrid (Spain); Cambeiro, Mauricio [Service of Radiation Oncology, Clínica Universidad de Navarra, Pamplona (Spain); Alvarez, Ana; Gonzalez, Carmen [Service of Radiation Oncology, Hospital General Universitario Gregorio Marañón, Madrid (Spain); Gonzalez, Jose [Service of Pediatric Orthopedics and Traumatology, Hospital General Universitario Gregorio Marañón, Madrid (Spain); San Julian, Mikel [Service of Orthopedics and Traumatology, Clínica Universidad de Navarra, Pamplona (Spain); Martinez-Monge, Rafael [Service of Radiation Oncology, Clínica Universidad de Navarra, Pamplona (Spain)

    2014-09-01

    Purpose: To perform a joint analysis of data from 3 contributing centers within the intraoperative electron-beam radiation therapy (IOERT)-Spanish program, to determine the potential of IOERT as an anticipated boost before external beam radiation therapy in the multidisciplinary treatment of pediatric extremity soft-tissue sarcomas. Methods and Materials: From June 1993 to May 2013, 62 patients (aged <21 years) with a histologic diagnosis of primary extremity soft-tissue sarcoma with absence of distant metastases, undergoing limb-sparing grossly resected surgery, external beam radiation therapy (median dose 40 Gy) and IOERT (median dose 10 Gy) were considered eligible for this analysis. Results: After a median follow-up of 66 months (range, 4-235 months), 10-year local control, disease-free survival, and overall survival was 85%, 76%, and 81%, respectively. In multivariate analysis after adjustment for other covariates, tumor size >5 cm (P=.04) and R1 margin status (P=.04) remained significantly associated with local relapse. In regard to overall survival only margin status (P=.04) retained association on multivariate analysis. Ten patients (16%) reported severe chronic toxicity events (all grade 3). Conclusions: An anticipated IOERT boost allowed for external beam radiation therapy dose reduction, with high local control and acceptably low toxicity rates. The combined radiosurgical approach needs to be tested in a prospective trial to confirm these results.

  8. Anticipated Intraoperative Electron Beam Boost, External Beam Radiation Therapy, and Limb-Sparing Surgical Resection for Patients with Pediatric Soft-Tissue Sarcomas of the Extremity: A Multicentric Pooled Analysis of Long-Term Outcomes

    International Nuclear Information System (INIS)

    Sole, Claudio V.; Calvo, Felipe A.; Polo, Alfredo; Cambeiro, Mauricio; Alvarez, Ana; Gonzalez, Carmen; Gonzalez, Jose; San Julian, Mikel; Martinez-Monge, Rafael

    2014-01-01

    Purpose: To perform a joint analysis of data from 3 contributing centers within the intraoperative electron-beam radiation therapy (IOERT)-Spanish program, to determine the potential of IOERT as an anticipated boost before external beam radiation therapy in the multidisciplinary treatment of pediatric extremity soft-tissue sarcomas. Methods and Materials: From June 1993 to May 2013, 62 patients (aged <21 years) with a histologic diagnosis of primary extremity soft-tissue sarcoma with absence of distant metastases, undergoing limb-sparing grossly resected surgery, external beam radiation therapy (median dose 40 Gy) and IOERT (median dose 10 Gy) were considered eligible for this analysis. Results: After a median follow-up of 66 months (range, 4-235 months), 10-year local control, disease-free survival, and overall survival was 85%, 76%, and 81%, respectively. In multivariate analysis after adjustment for other covariates, tumor size >5 cm (P=.04) and R1 margin status (P=.04) remained significantly associated with local relapse. In regard to overall survival only margin status (P=.04) retained association on multivariate analysis. Ten patients (16%) reported severe chronic toxicity events (all grade 3). Conclusions: An anticipated IOERT boost allowed for external beam radiation therapy dose reduction, with high local control and acceptably low toxicity rates. The combined radiosurgical approach needs to be tested in a prospective trial to confirm these results

  9. Regression analysis of mixed recurrent-event and panel-count data.

    Science.gov (United States)

    Zhu, Liang; Tong, Xinwei; Sun, Jianguo; Chen, Manhua; Srivastava, Deo Kumar; Leisenring, Wendy; Robison, Leslie L

    2014-07-01

    In event history studies concerning recurrent events, two types of data have been extensively discussed. One is recurrent-event data (Cook and Lawless, 2007. The Analysis of Recurrent Event Data. New York: Springer), and the other is panel-count data (Zhao and others, 2010. Nonparametric inference based on panel-count data. Test 20: , 1-42). In the former case, all study subjects are monitored continuously; thus, complete information is available for the underlying recurrent-event processes of interest. In the latter case, study subjects are monitored periodically; thus, only incomplete information is available for the processes of interest. In reality, however, a third type of data could occur in which some study subjects are monitored continuously, but others are monitored periodically. When this occurs, we have mixed recurrent-event and panel-count data. This paper discusses regression analysis of such mixed data and presents two estimation procedures for the problem. One is a maximum likelihood estimation procedure, and the other is an estimating equation procedure. The asymptotic properties of both resulting estimators of regression parameters are established. Also, the methods are applied to a set of mixed recurrent-event and panel-count data that arose from a Childhood Cancer Survivor Study and motivated this investigation. © The Author 2014. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  10. Risk-Informed External Hazards Analysis for Seismic and Flooding Phenomena for a Generic PWR

    Energy Technology Data Exchange (ETDEWEB)

    Parisi, Carlo [Idaho National Lab. (INL), Idaho Falls, ID (United States); Prescott, Steve [Idaho National Lab. (INL), Idaho Falls, ID (United States); Ma, Zhegang [Idaho National Lab. (INL), Idaho Falls, ID (United States); Spears, Bob [Idaho National Lab. (INL), Idaho Falls, ID (United States); Szilard, Ronaldo [Idaho National Lab. (INL), Idaho Falls, ID (United States); Coleman, Justin [Idaho National Lab. (INL), Idaho Falls, ID (United States); Kosbab, Ben [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2017-07-26

    This report describes the activities performed during the FY2017 for the US-DOE Light Water Reactor Sustainability Risk-Informed Safety Margin Characterization (LWRS-RISMC), Industry Application #2. The scope of Industry Application #2 is to deliver a risk-informed external hazards safety analysis for a representative nuclear power plant. Following the advancements occurred during the previous FYs (toolkits identification, models development), FY2017 focused on: increasing the level of realism of the analysis; improving the tools and the coupling methodologies. In particular the following objectives were achieved: calculation of buildings pounding and their effects on components seismic fragility; development of a SAPHIRE code PRA models for 3-loops Westinghouse PWR; set-up of a methodology for performing static-dynamic PRA coupling between SAPHIRE and EMRALD codes; coupling RELAP5-3D/RAVEN for performing Best-Estimate Plus Uncertainty analysis and automatic limit surface search; and execute sample calculations for demonstrating the capabilities of the toolkit in performing a risk-informed external hazards safety analyses.

  11. Initiating Event Analysis of a Lithium Fluoride Thorium Reactor

    Science.gov (United States)

    Geraci, Nicholas Charles

    The primary purpose of this study is to perform an Initiating Event Analysis for a Lithium Fluoride Thorium Reactor (LFTR) as the first step of a Probabilistic Safety Assessment (PSA). The major objective of the research is to compile a list of key initiating events capable of resulting in failure of safety systems and release of radioactive material from the LFTR. Due to the complex interactions between engineering design, component reliability and human reliability, probabilistic safety assessments are most useful when the scope is limited to a single reactor plant. Thus, this thesis will study the LFTR design proposed by Flibe Energy. An October 2015 Electric Power Research Institute report on the Flibe Energy LFTR asked "what-if?" questions of subject matter experts and compiled a list of key hazards with the most significant consequences to the safety or integrity of the LFTR. The potential exists for unforeseen hazards to pose additional risk for the LFTR, but the scope of this thesis is limited to evaluation of those key hazards already identified by Flibe Energy. These key hazards are the starting point for the Initiating Event Analysis performed in this thesis. Engineering evaluation and technical study of the plant using a literature review and comparison to reference technology revealed four hazards with high potential to cause reactor core damage. To determine the initiating events resulting in realization of these four hazards, reference was made to previous PSAs and existing NRC and EPRI initiating event lists. Finally, fault tree and event tree analyses were conducted, completing the logical classification of initiating events. Results are qualitative as opposed to quantitative due to the early stages of system design descriptions and lack of operating experience or data for the LFTR. In summary, this thesis analyzes initiating events using previous research and inductive and deductive reasoning through traditional risk management techniques to

  12. Conversion of neurons and glia to external-cell fates in the external sensory organs of Drosophila hamlet mutants by a cousin-cousin cell-type respecification.

    Science.gov (United States)

    Moore, Adrian W; Roegiers, Fabrice; Jan, Lily Y; Jan, Yuh-Nung

    2004-03-15

    The Drosophila external sensory organ forms in a lineage elaborating from a single precursor cell via a stereotypical series of asymmetric divisions. HAMLET transcription factor expression demarcates the lineage branch that generates two internal cell types, the external sensory neuron and thecogen. In HAMLET mutant organs, these internal cells are converted to external cells via an unprecedented cousin-cousin cell-fate respecification event. Conversely, ectopic HAMLET expression in the external cell branch leads to internal cell production. The fate-determining signals NOTCH and PAX2 act at multiple stages of lineage elaboration and HAMLET acts to modulate their activity in a branch-specific manner.

  13. Analysis of Sustainable Performance in Romania’s Local Public Administrations: An External Stakeholders Perspective

    Directory of Open Access Journals (Sweden)

    Diana MIHAIU

    2016-12-01

    Full Text Available Building a sustainable performance system at the level of the local public administrations must have as starting point the local public administration’s (LPA mission and must go down to the level of the individual. This system must follow the external performance that it delivers to the citizens, the outcomes generated, but also the internal performance which suggests how to achieve the external performance. We propose in this regard the simultaneous use of the Balanced Scorecard tool for managing the internal performance and the Public Service Value Model for measuring the external performance measurement which derives from the organization's mission. In the second part of the work we analyzed comparatively the external performance created by the county capitals of Romania in the year 2013 using the Public Service Value Model (PSVM. Based on this analysis, the county capitals of Romania can be divided in the following categories: high performance organizations (value driven, budget conscious organizations, low performance organizations (sleeping giants and quality conscious organizations. This classification is useful both for the external and internal stakeholders because it shows the efficiency of public money spending and the areas in which the LPA is performing well, and also the ones that need to be improved.

  14. Uncertainty analysis of one Main Circulation Pump trip event at the Ignalina NPP

    International Nuclear Information System (INIS)

    Vileiniskis, V.; Kaliatka, A.; Uspuras, E.

    2004-01-01

    One Main Circulation Pump (MCP) trip event is an anticipated transient with expected frequency of approximately one event per year. There were a few events when one MCP was inadvertently tripped. The throughput of the rest running pumps in the affected Main Circulation Circuit loop increased, however, the total coolant flow through the affected loop decreased. The main question arises whether this coolant flow rate is sufficient for adequate core cooling. This paper presents an investigation of one MCP trip event at the Ignalina NPP. According to international practice, the transient analysis should consist of deterministic analysis by employing best-estimate codes and uncertainty analysis. For that purpose, the plant's RELAP5 model and the GRS (Germany) System for Uncertainty and Sensitivity Analysis package (SUSA) were employed. Uncertainty analysis of flow energy loss in different parts of the Main Circulation Circuit, initial conditions and code-selected models was performed. Such analysis allows to estimate the influence of separate parameters on calculation results and to find the modelling parameters that have the largest impact on the event studied. On the basis of this analysis, recommendations for the further improvement of the model have been developed. (author)

  15. Inside-out: comparing internally generated and externally generated basic emotions.

    Science.gov (United States)

    Salas, Christian E; Radovic, Darinka; Turnbull, Oliver H

    2012-06-01

    A considerable number of mood induction (MI) procedures have been developed to elicit emotion in normal and clinical populations. Although external procedures (e.g., film clips, pictures) are widely used, a number of experiments elicit emotion by using self-generated procedures (e.g., recalling an emotional personal episode). However, no study has directly compared the effectiveness of two types of internal versus external MI across multiple discrete emotions. In the present experiment, 40 undergraduate students watched film clips (external procedure) and recalled personal events (internal procedure) inducing 4 basic emotions (fear, anger, joy, sadness) and later completed a self-report questionnaire. Remarkably, both internal and external procedures elicited target emotions selectively, compared with nontarget emotions. When contrasting the intensity of target emotions, both techniques showed no significant differences, with the exception of Joy, which was more intensely elicited by the internal procedure. Importantly, when considering the overall level of intensity, it was always greater in the internal procedure, for each stimulus. A more detailed investigation of the data suggest that recalling personal events (a type of internal procedure) generates more negative and mixed blends of emotions, which might account for the overall higher intensity of the internal mood induction.

  16. Root Cause Analysis: Learning from Adverse Safety Events.

    Science.gov (United States)

    Brook, Olga R; Kruskal, Jonathan B; Eisenberg, Ronald L; Larson, David B

    2015-10-01

    Serious adverse events continue to occur in clinical practice, despite our best preventive efforts. It is essential that radiologists, both as individuals and as a part of organizations, learn from such events and make appropriate changes to decrease the likelihood that such events will recur. Root cause analysis (RCA) is a process to (a) identify factors that underlie variation in performance or that predispose an event toward undesired outcomes and (b) allow for development of effective strategies to decrease the likelihood of similar adverse events occurring in the future. An RCA process should be performed within the environment of a culture of safety, focusing on underlying system contributors and, in a confidential manner, taking into account the emotional effects on the staff involved. The Joint Commission now requires that a credible RCA be performed within 45 days for all sentinel or major adverse events, emphasizing the need for all radiologists to understand the processes with which an effective RCA can be performed. Several RCA-related tools that have been found to be useful in the radiology setting include the "five whys" approach to determine causation; cause-and-effect, or Ishikawa, diagrams; causal tree mapping; affinity diagrams; and Pareto charts. © RSNA, 2015.

  17. [Complications of open reduction and internal fixation versus external fixation for unstable distal radius fractures: a meta-analysis].

    Science.gov (United States)

    Yang, Z; Yuan, Z Z; Ma, J X; Ma, X L

    2016-12-20

    Objective: To make a systematic assessment of the complications of open reduction and internal fixation versus external fixation for unstable distal radius fractures. Method: A computer-based online search of PubMed, ScienceDirect, EMBASE, BIOSIS, Springer and Cochrane Library were performed.The randomized and controlled trials of open reduction and internal fixation versus external fixation for unstable distal radius fractures were collected.The included trials were screened out strictly based on the criterion of inclusion and exclusion.The quality of included trials was evaluated.RevMan 5.0 was used for data analysis. Result: A total of 17 studies involving 1 402 patients were included.There were 687 patients with open reduction and internal fixation and 715 with external fixation.The results of Meta-analysis indicated that there were statistically significant differences with regard to the postoperatively total complications, infection, malunion, tendon rupture ( I 2 =8%, RR =0.77(95% CI 0.65-0.91, Z =3.10, P 0.05). Conclusion: Postoperative complications are present in both open reduction and internal fixation and external fixation.Compared with external fixation, open reduction and internal fixation is lower in total complications postoperatively, infection and malunion, but external fixation has lower tendon rupture incidence.

  18. Analysis of human error and organizational deficiency in events considering risk significance

    International Nuclear Information System (INIS)

    Lee, Yong Suk; Kim, Yoonik; Kim, Say Hyung; Kim, Chansoo; Chung, Chang Hyun; Jung, Won Dea

    2004-01-01

    In this study, we analyzed human and organizational deficiencies in the trip events of Korean nuclear power plants. K-HPES items were used in human error analysis, and the organizational factors by Jacobs and Haber were used for organizational deficiency analysis. We proposed the use of CCDP as a risk measure to consider risk information in prioritizing K-HPES items and organizational factors. Until now, the risk significance of events has not been considered in human error and organizational deficiency analysis. Considering the risk significance of events in the process of analysis is necessary for effective enhancement of nuclear power plant safety by focusing on causes of human error and organizational deficiencies that are associated with significant risk

  19. Difference Image Analysis of Galactic Microlensing. II. Microlensing Events

    Energy Technology Data Exchange (ETDEWEB)

    Alcock, C.; Allsman, R. A.; Alves, D.; Axelrod, T. S.; Becker, A. C.; Bennett, D. P.; Cook, K. H.; Drake, A. J.; Freeman, K. C.; Griest, K. (and others)

    1999-09-01

    The MACHO collaboration has been carrying out difference image analysis (DIA) since 1996 with the aim of increasing the sensitivity to the detection of gravitational microlensing. This is a preliminary report on the application of DIA to galactic bulge images in one field. We show how the DIA technique significantly increases the number of detected lensing events, by removing the positional dependence of traditional photometry schemes and lowering the microlensing event detection threshold. This technique, unlike PSF photometry, gives the unblended colors and positions of the microlensing source stars. We present a set of criteria for selecting microlensing events from objects discovered with this technique. The 16 pixel and classical microlensing events discovered with the DIA technique are presented. (c) (c) 1999. The American Astronomical Society.

  20. Civil protection and Damaging Hydrogeological Events: comparative analysis of the 2000 and 2015 events in Calabria (southern Italy

    Directory of Open Access Journals (Sweden)

    O. Petrucci

    2017-11-01

    Full Text Available Calabria (southern Italy is a flood prone region, due to both its rough orography and fast hydrologic response of most watersheds. During the rainy season, intense rain affects the region, triggering floods and mass movements that cause economic damage and fatalities. This work presents a methodological approach to perform the comparative analysis of two events affecting the same area at a distance of 15 years, by collecting all the qualitative and quantitative features useful to describe both rain and damage. The aim is to understand if similar meteorological events affecting the same area can have different outcomes in terms of damage. The first event occurred between 8 and 10 September 2000, damaged 109 out of 409 municipalities of the region and killed 13 people in a campsite due to a flood. The second event, which occurred between 30 October and 1 November 2015, damaged 79 municipalities, and killed a man due to a flood. The comparative analysis highlights that, despite the exceptionality of triggering daily rain was higher in the 2015 event, the damage caused by the 2000 event to both infrastructures and belongings was higher, and it was strongly increased due to the 13 flood victims. We concluded that, in the 2015 event, the management of pre-event phases, with the issuing of meteorological alert, and the emergency management, with the preventive evacuation of people in hazardous situations due to landslides or floods, contributed to reduce the number of victims.

  1. Analysis of operational events by ATHEANA framework for human factor modelling

    International Nuclear Information System (INIS)

    Bedreaga, Luminita; Constntinescu, Cristina; Doca, Cezar; Guzun, Basarab

    2007-01-01

    In the area of human reliability assessment, the experts recognise the fact that the current methods have not represented correctly the role of human in prevention, initiating and mitigating the accidents in nuclear power plants. The nature of this deficiency appears because the current methods used in modelling of human factor have not taken into account the human performance and reliability such as it has been observed in the operational events. ATHEANA - A Technique for Human Error ANAlysis - is a new methodology for human analysis that has included the specific data of operational events and also psychological models for human behaviour. This method has included new elements such as the unsafe action and error mechanisms. In this paper we present the application of ATHEANA framework in the analysis of operational events that appeared in different nuclear power plants during 1979-2002. The analysis of operational events has consisted of: - identification of the unsafe actions; - including the unsafe actions into a category, omission ar commission; - establishing the type of error corresponding to the unsafe action: slip, lapse, mistake and circumvention; - establishing the influence of performance by shaping the factors and some corrective actions. (authors)

  2. Retrofitting Systems for External Walls

    DEFF Research Database (Denmark)

    Rose, Jørgen

    1997-01-01

    In this report, 9 different external and internal retrofitting systems are analyzed using numerical calculations. The analysis focuses on the thermal bridge effects in the different systems, and on this basis it is discussed whether internal or external retrofitting has the most advantages...

  3. Treatment of external hazards in probabilistic safety assessment for nuclear power plants. A Safety Practice

    International Nuclear Information System (INIS)

    1995-01-01

    This Safety Practice provides guidance on conducting a PSA for external hazards in nuclear power plants. Emphasis is placed on the procedural steps of the PSA rather then on the details of corresponding methods. The publication is intended to assist technical persons managing or performing PSAs. A particular aim is to promote a standardized framework, terminology and form of documentation for external hazards PSA so as to facilitate external review of the results of such studies. For those specialists who are already involved in related studies, such as a Level 1 PSA dealing only with internal events, this publication provides an indication of how additional external events could be integrated into an existing PSA. 16 refs, 5 figs, 2 tabs

  4. Productivity Change and Externalities

    DEFF Research Database (Denmark)

    Kravtsova, Victoria

    2014-01-01

    This paper contributes to the analysis of the impact of externalities on the host country's total factor productivity by taking into account different dimensions of spillover effects. Namely, engagement in exporting and foreign ownership is generally perceived as being beneficial to individual...... firms and the economy as a whole. The approach used in the current research accounts for different internal as well as external factors that individual firms face and evaluates the effect on changes in productivity, technology as well as the efficiency of domestic firms. The empirical analysis focuses...... on Hungary. While the country leads the group of post-socialist countries in the amount of attracted foreign direct investments (FDI) the effect of this policy on the economy remains unclear. The research finds that different externalities play a different role in productivity, technological and efficiency...

  5. Event horizon image within black hole shadow

    OpenAIRE

    Dokuchaev, V. I.; Nazarova, N. O.

    2018-01-01

    The external border of the black hole shadow is washed out by radiation from matter plunging into black hole and approaching the event horizon. This effect will crucially influence the results of future observations by the Event Horizon Telescope. We show that gravitational lensing of the luminous matter plunging into black hole provides the event horizon visualization within black hole shadow. The lensed image of the event horizon is formed by the last highly red-shifted photons emitted by t...

  6. 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.)

  7. Operationalizing Proneness to Externalizing Psychopathology as a Multivariate Psychophysiological Phenotype

    Science.gov (United States)

    Nelson, Lindsay D.; Patrick, Christopher J.; Bernat, Edward M.

    2010-01-01

    The externalizing dimension is viewed as a broad dispositional factor underlying risk for numerous disinhibitory disorders. Prior work has documented deficits in event-related brain potential (ERP) responses in individuals prone to externalizing problems. Here, we constructed a direct physiological index of externalizing vulnerability from three ERP indicators and evaluated its validity in relation to criterion measures in two distinct domains: psychometric and physiological. The index was derived from three ERP measures that covaried in their relations with externalizing proneness the error-related negativity and two variants of the P3. Scores on this ERP composite predicted psychometric criterion variables and accounted for externalizing-related variance in P3 response from a separate task. These findings illustrate how a diagnostic construct can be operationalized as a composite (multivariate) psychophysiological variable (phenotype). PMID:20573054

  8. Software failure events derivation and analysis by frame-based technique

    International Nuclear Information System (INIS)

    Huang, H.-W.; Shih, C.; Yih, Swu; Chen, M.-H.

    2007-01-01

    A frame-based technique, including physical frame, logical frame, and cognitive frame, was adopted to perform digital I and C failure events derivation and analysis for generic ABWR. The physical frame was structured with a modified PCTran-ABWR plant simulation code, which was extended and enhanced on the feedwater system, recirculation system, and steam line system. The logical model is structured with MATLAB, which was incorporated into PCTran-ABWR to improve the pressure control system, feedwater control system, recirculation control system, and automated power regulation control system. As a result, the software failure of these digital control systems can be properly simulated and analyzed. The cognitive frame was simulated by the operator awareness status in the scenarios. Moreover, via an internal characteristics tuning technique, the modified PCTran-ABWR can precisely reflect the characteristics of the power-core flow. Hence, in addition to the transient plots, the analysis results can then be demonstrated on the power-core flow map. A number of postulated I and C system software failure events were derived to achieve the dynamic analyses. The basis for event derivation includes the published classification for software anomalies, the digital I and C design data for ABWR, chapter 15 accident analysis of generic SAR, and the reported NPP I and C software failure events. The case study of this research includes: (1) the software CMF analysis for the major digital control systems; and (2) postulated ABWR digital I and C software failure events derivation from the actual happening of non-ABWR digital I and C software failure events, which were reported to LER of USNRC or IRS of IAEA. These events were analyzed by PCTran-ABWR. Conflicts among plant status, computer status, and human cognitive status are successfully identified. The operator might not easily recognize the abnormal condition, because the computer status seems to progress normally. However, a well

  9. Realistic modelling of external flooding scenarios - A multi-disciplinary approach

    International Nuclear Information System (INIS)

    Brinkman, J.L.

    2014-01-01

    Extreme phenomena, such as storm surges or high river water levels, may endanger the safety of nuclear power plants (NPPs) by inundation of the plant site with subsequent damage on safety-related buildings. Flooding may result in simultaneous failures of safety-related components, such as service water pumps and electrical equipment. In addition, the accessibility of the plant may be impeded due to flooding of the plant environment. These consequences are so severe that, (re)assessments of flood risk and flood protection measures should be based on accurate state-of-the-art methods. Dutch nuclear regulations require that a nuclear power plant shall withstand all external initiating events with a return period lower than one million years. For external flooding, this requirement is the basis of the so-called nuclear design level (nucleair ontwerp peil, NOP) of the buildings for external flooding, i.e. the water level at which a system - among others, the nuclear island and the ultimate heat sink - should still function properly. In determining the NOP, the mean water level, wave height and wave behaviour during storm surges are taken into account. This concept could also be used to implement external flooding in a PSA, by assuming that floods exceeding NOP levels directly lead to core damage. However, this straightforward modelling ignores some important aspects: the first is the mitigating effect of the external flood protection as dikes or dunes; the second aspect is that although water levels lower than NOP will not directly lead to core damage, they could do so indirectly as a result of combinations of system loss by flooding and random failure of required safety systems that have to bring the plant in a safe, stable state. Time is a third aspect: failure mechanisms need time to develop and time (via duration of the flood) determines the amount of water on site. This paper describes a PSA approach that takes the (structural) reliability of the external defences

  10. An analysis of post-event processing in social anxiety disorder.

    Science.gov (United States)

    Brozovich, Faith; Heimberg, Richard G

    2008-07-01

    Research has demonstrated that self-focused thoughts and negative affect have a reciprocal relationship [Mor, N., Winquist, J. (2002). Self-focused attention and negative affect: A meta-analysis. Psychological Bulletin, 128, 638-662]. In the anxiety disorder literature, post-event processing has emerged as a specific construction of repetitive self-focused thoughts that pertain to social anxiety disorder. Post-event processing can be defined as an individual's repeated consideration and potential reconstruction of his performance following a social situation. Post-event processing can also occur when an individual anticipates a social or performance event and begins to brood about other, past social experiences. The present review examined the post-event processing literature in an attempt to organize and highlight the significant results. The methodologies employed to study post-event processing have included self-report measures, daily diaries, social or performance situations created in the laboratory, and experimental manipulations of post-event processing or anticipation of an upcoming event. Directions for future research on post-event processing are discussed.

  11. Nonlinear analysis of reinforced concrete structures subjected to high temperature and external load

    International Nuclear Information System (INIS)

    Sugawara, Y.; Goto, M.; Saito, K.; Suzuki, N.; Muto, A.; Ueda, M.

    1993-01-01

    A quarter of a century has passed since the finite element method was first applied to nonlinear problems concerning reinforced concrete structures, and the reliability of the analysis at ordinary temperature has been enhanced accordingly. By contrast, few studies have tried to deal with the nonlinear behavior of reinforced concrete structures subjected to high temperature and external loads simultaneously. It is generally known that the mechanical properties of concrete and steel are affected greatly by temperature. Therefore, in order to analyze the nonlinear behavior of reinforced concrete subjected to external loads at high temperature, it is necessary to construct constitutive models of the materials reflecting the influence of temperature. In this study, constitutive models of concrete and reinforcement that can express decreases in strength and stiffness at high temperature have been developed. A two-dimensional nonlinear finite element analysis program has been developed by use of these material models. The behavior of reinforced concrete beams subjected simultaneously to high temperature and shear forces were simulated using the developed analytical method. The results of the simulation agreed well with the experimental results, evidencing the validity of the developed material models and the finite element analysis program

  12. Integrating natural language processing expertise with patient safety event review committees to improve the analysis of medication events.

    Science.gov (United States)

    Fong, Allan; Harriott, Nicole; Walters, Donna M; Foley, Hanan; Morrissey, Richard; Ratwani, Raj R

    2017-08-01

    Many healthcare providers have implemented patient safety event reporting systems to better understand and improve patient safety. Reviewing and analyzing these reports is often time consuming and resource intensive because of both the quantity of reports and length of free-text descriptions in the reports. Natural language processing (NLP) experts collaborated with clinical experts on a patient safety committee to assist in the identification and analysis of medication related patient safety events. Different NLP algorithmic approaches were developed to identify four types of medication related patient safety events and the models were compared. Well performing NLP models were generated to categorize medication related events into pharmacy delivery delays, dispensing errors, Pyxis discrepancies, and prescriber errors with receiver operating characteristic areas under the curve of 0.96, 0.87, 0.96, and 0.81 respectively. We also found that modeling the brief without the resolution text generally improved model performance. These models were integrated into a dashboard visualization to support the patient safety committee review process. We demonstrate the capabilities of various NLP models and the use of two text inclusion strategies at categorizing medication related patient safety events. The NLP models and visualization could be used to improve the efficiency of patient safety event data review and analysis. Copyright © 2017 Elsevier B.V. All rights reserved.

  13. Disruptive event analysis: volcanism and igneous intrusion

    International Nuclear Information System (INIS)

    Crowe, B.M.

    1979-01-01

    Three basic topics are addressed for the disruptive event analysis: first, the range of disruptive consequences of a radioactive waste repository by volcanic activity; second, the possible reduction of the risk of disruption by volcanic activity through selective siting of a repository; and third, the quantification of the probability of repository disruption by volcanic activity

  14. Adverse Events Involving Radiation Oncology Medical Devices: Comprehensive Analysis of US Food and Drug Administration Data, 1991 to 2015

    International Nuclear Information System (INIS)

    Connor, Michael J.; Marshall, Deborah C.; Moiseenko, Vitali; Moore, Kevin; Cervino, Laura; Atwood, Todd; Sanghvi, Parag; Mundt, Arno J.; Pawlicki, Todd; Recht, Abram; Hattangadi-Gluth, Jona A.

    2017-01-01

    Purpose: Radiation oncology relies on rapidly evolving technology and highly complex processes. The US Food and Drug Administration collects reports of adverse events related to medical devices. We sought to characterize all events involving radiation oncology devices (RODs) from the US Food and Drug Administration's postmarket surveillance Manufacturer and User Facility Device Experience (MAUDE) database, comparing these with non–radiation oncology devices. Methods and Materials: MAUDE data on RODs from 1991 to 2015 were sorted into 4 product categories (external beam, brachytherapy, planning systems, and simulation systems) and 5 device problem categories (software, mechanical, electrical, user error, and dose delivery impact). Outcomes included whether the device was evaluated by the manufacturer, adverse event type, remedial action, problem code, device age, and time since 510(k) approval. Descriptive statistics were performed with linear regression of time-series data. Results for RODs were compared with those for other devices by the Pearson χ"2 test for categorical data and 2-sample Kolmogorov-Smirnov test for distributions. Results: There were 4234 ROD and 4,985,698 other device adverse event reports. Adverse event reports increased over time, and events involving RODs peaked in 2011. Most ROD reports involved external beam therapy (50.8%), followed by brachytherapy (24.9%) and treatment planning systems (21.6%). The top problem types were software (30.4%), mechanical (20.9%), and user error (20.4%). RODs differed significantly from other devices in each outcome (P<.001). RODs were more likely to be evaluated by the manufacturer after an event (46.9% vs 33.0%) but less likely to be recalled (10.5% vs 37.9%) (P<.001). Device age and time since 510(k) approval were shorter among RODs (P<.001). Conclusions: Compared with other devices, RODs may experience adverse events sooner after manufacture and market approval. Close postmarket surveillance, improved

  15. Adverse Events Involving Radiation Oncology Medical Devices: Comprehensive Analysis of US Food and Drug Administration Data, 1991 to 2015

    Energy Technology Data Exchange (ETDEWEB)

    Connor, Michael J. [Department of Radiation Medicine and Applied Sciences, University of California San Diego, La Jolla, California (United States); Department of Radiation Oncology, University of California Irvine School of Medicine, Irvine, California (United States); Marshall, Deborah C.; Moiseenko, Vitali; Moore, Kevin; Cervino, Laura; Atwood, Todd; Sanghvi, Parag; Mundt, Arno J.; Pawlicki, Todd [Department of Radiation Medicine and Applied Sciences, University of California San Diego, La Jolla, California (United States); Recht, Abram [Department of Radiation Oncology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts (United States); Hattangadi-Gluth, Jona A., E-mail: jhattangadi@ucsd.edu [Department of Radiation Medicine and Applied Sciences, University of California San Diego, La Jolla, California (United States)

    2017-01-01

    Purpose: Radiation oncology relies on rapidly evolving technology and highly complex processes. The US Food and Drug Administration collects reports of adverse events related to medical devices. We sought to characterize all events involving radiation oncology devices (RODs) from the US Food and Drug Administration's postmarket surveillance Manufacturer and User Facility Device Experience (MAUDE) database, comparing these with non–radiation oncology devices. Methods and Materials: MAUDE data on RODs from 1991 to 2015 were sorted into 4 product categories (external beam, brachytherapy, planning systems, and simulation systems) and 5 device problem categories (software, mechanical, electrical, user error, and dose delivery impact). Outcomes included whether the device was evaluated by the manufacturer, adverse event type, remedial action, problem code, device age, and time since 510(k) approval. Descriptive statistics were performed with linear regression of time-series data. Results for RODs were compared with those for other devices by the Pearson χ{sup 2} test for categorical data and 2-sample Kolmogorov-Smirnov test for distributions. Results: There were 4234 ROD and 4,985,698 other device adverse event reports. Adverse event reports increased over time, and events involving RODs peaked in 2011. Most ROD reports involved external beam therapy (50.8%), followed by brachytherapy (24.9%) and treatment planning systems (21.6%). The top problem types were software (30.4%), mechanical (20.9%), and user error (20.4%). RODs differed significantly from other devices in each outcome (P<.001). RODs were more likely to be evaluated by the manufacturer after an event (46.9% vs 33.0%) but less likely to be recalled (10.5% vs 37.9%) (P<.001). Device age and time since 510(k) approval were shorter among RODs (P<.001). Conclusions: Compared with other devices, RODs may experience adverse events sooner after manufacture and market approval. Close postmarket surveillance

  16. Organization of pulse-height analysis programs for high event rates

    Energy Technology Data Exchange (ETDEWEB)

    Cohn, C E [Argonne National Lab., Ill. (USA)

    1976-09-01

    The ability of a pulse-height analysis program to handle high event rates can be enhanced by organizing it so as to minimize the time spent in interrupt housekeeping. Specifically, the routine that services the data-ready interrupt from the ADC should test whether another event is ready before performing the interrupt return.

  17. Historical estimates of external gamma exposure and collective external gamma exposure from testing at the Nevada Test Site. I. Test series through HARDTACK II, 1958

    Energy Technology Data Exchange (ETDEWEB)

    Anspaugh, L.R.; Church, B.W.

    1985-12-01

    In 1959, the Test Manager's Committee to Establish Fallout Doses calculated estimated external gamma exposure at populated locations based upon measurements of external gamma-exposure rate. Using these calculations and estimates of population, we have tabulated the collective estimated external gamma exposures for communities within established fallout patterns. The total collective estimated external gamma exposure is 85,000 person-R. The greatest collective exposures occurred in three general areas: Saint George, Utah; Ely, Nevada; and Las Vegas, Nevada. Three events, HARRY (May 19, 1953), BEE (March 22, 1955), and SMOKY (August 31, 1957), accounted for over half of the total collective estimated external gamma exposure. The bases of the calculational models for external gamma exposure of ''infinite exposure,'' ''estimated exposure,'' and ''one year effective biological exposure'' are explained. 4 figs., 7 tabs.

  18. External costs of electricity

    International Nuclear Information System (INIS)

    Rabl, A.; Spadaro, J.V.

    2005-01-01

    This article presents a synthesis of the ExternE project (External costs of Energy) of the European community about the external costs of power generation. Pollution impacts are calculated using an 'impact pathways' analysis, i.e. an analysis of the emission - dispersion - dose-response function - cost evaluation chain. Results are presented for different fuel cycles (with several technological variants) with their confidence intervals. The environmental impact costs are particularly high for coal: for instance, in France, for coal-fired power plants it is of the same order as the electricity retail price. For natural gas, this cost is about a third of the one for coal. On the contrary, the environmental impact costs for nuclear and renewable energies are low, typically of few per cent of the electricity price. The main part of these costs corresponds to the sanitary impacts, in particular the untimely mortality. In order to avoid any controversy about the cost evaluation of mortality, the reduction of the expectation of life due to the different fuel cycles is also indicated and the risks linked with nuclear energy are presented using several comparisons. (J.S.)

  19. Procedure for following external nuclear power plant operating experience

    International Nuclear Information System (INIS)

    Kostadinov, V.

    2003-01-01

    Slovenian Nuclear Safety Administration (SNSA) has developed computer database and the procedure for following-up and investigating external nuclear operating experience and administrative requirements. The SNSA's primary goal is to investigate safety significant events in due time, to analyze them from the regulatory point of view and to ensure that meaningful lessons be learned and used for improvement of the safe operation of Slovenian Nuclear Power Plant Krsko. Moreover, we intend to make uniform format and method for reporting broader spectrum of events analyzed including low level event reporting. (author)

  20. External effects and social costs of road transport

    NARCIS (Netherlands)

    Verhoef, E.T.

    1994-01-01

    The article contains a welfare economic analysis of road transport's external effects. First, we discuss the definition of external effects. Applying this definition, it is concluded that road transport activities give rise to a wide range of external costs. However, there are no external benefits

  1. NPP Siting in Western Part of Java Island Indonesia: Regional Analysis Stage

    International Nuclear Information System (INIS)

    Sastratenaya, A.S.; Yuliastuti

    2011-01-01

    Full text of publication follows: Considering that Banten and West Java Provinces are dense regions of industry, therefore they require a large amount of electricity. Nuclear power plant is one option to be considered to anticipate the future electricity demand. To support the program, it is needed to look for some potential locations through NPP siting. The siting should meet the requirement of safety, safety aspects of the natural external events, human induced external events, public and environmental safety. Site selection is performed in several stages, where each stage has specific assessment criteria. Siting is commenced with pre-survey activity to obtain several interest areas, the activity covers a wide area but the used data is very limited and only apply general criteria. The following activities after pre survey are site survey consisting of (1) regional analysis, (2) site screening, and (3) comparison and ranking stages. The objective of regional analysis is to obtain potential sites in the study area of 150 km radius from each interest area by using both general and specific criteria. The potential sites then screened to obtain selected candidate sites by using more detailed secondary data as well as survey activities such as geophysical investigation, a few of drilling, etc., within the radius of 50 km from each potential site. All the selected candidate sites are then compared and ranked to obtain preferred candidate site. Site evaluation is the next step to evaluate all site-specific parameter to obtain design basis parameters and as the basis for preparing site permit document. This paper presents the methodology and result of regional analysis stage. The objective of the activity is to obtain potential sites in the north coast of West Java and Banten Provinces by considering fourteen study aspects which could be categorize into safety related aspects, non-safety related aspect and public education. However, this paper only considers the safety

  2. 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.

  3. Transient Analysis of Grid-Connected Wind Turbines with DFIG After an External Short-Circuit Fault

    DEFF Research Database (Denmark)

    Sun, Tao; Chen, Zhe; Blaabjerg, Frede

    2004-01-01

    The fast development of wind power generation brings new requirements for wind turbine integration to the network. After the clearance of an external short-circuit fault, the grid-connected wind turbine should restore its normal operation with minimized power losses. This paper concentrates...... on transient analysis of variable speed wind turbines with doubly fed induction generator (DFIG) after an external short-circuit fault. A simulation model of a MW-level variable speed wind turbine with DFIG developed in PSCAD/EMTDC is presented, and the control and protection schemes are described in detail....... After the clearance of an external short-circuit fault the control schemes manage to restore the wind turbine?s normal operation, and their performances are demonstrated by simulation results both during the fault and after the clearance of the fault....

  4. 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)

  5. Microprocessor event analysis in parallel with Camac data acquisition

    International Nuclear Information System (INIS)

    Cords, D.; Eichler, R.; Riege, H.

    1981-01-01

    The Plessey MIPROC-16 microprocessor (16 bits, 250 ns execution time) has been connected to a Camac System (GEC-ELLIOTT System Crate) and shares the Camac access with a Nord-1OS computer. Interfaces have been designed and tested for execution of Camac cycles, communication with the Nord-1OS computer and DMA-transfer from Camac to the MIPROC-16 memory. The system is used in the JADE data-acquisition-system at PETRA where it receives the data from the detector in parallel with the Nord-1OS computer via DMA through the indirect-data-channel mode. The microprocessor performs an on-line analysis of events and the result of various checks is appended to the event. In case of spurious triggers or clear beam gas events, the Nord-1OS buffer will be reset and the event omitted from further processing. (orig.)

  6. ExternE transport methodology for external cost evaluation of air pollution

    DEFF Research Database (Denmark)

    Jensen, S. S.; Berkowicz, R.; Brandt, J.

    The report describes how the human exposure estimates based on NERI's human exposure modelling system (AirGIS) can improve the Danish data used for exposure factors in the ExternE Transport methodology. Initially, a brief description of the ExternE Tranport methodology is given and it is summarised...

  7. Using discriminant analysis as a nucleation event classification method

    Directory of Open Access Journals (Sweden)

    S. Mikkonen

    2006-01-01

    Full Text Available More than three years of measurements of aerosol size-distribution and different gas and meteorological parameters made in Po Valley, Italy were analysed for this study to examine which of the meteorological and trace gas variables effect on the emergence of nucleation events. As the analysis method, we used discriminant analysis with non-parametric Epanechnikov kernel, included in non-parametric density estimation method. The best classification result in our data was reached with the combination of relative humidity, ozone concentration and a third degree polynomial of radiation. RH appeared to have a preventing effect on the new particle formation whereas the effects of O3 and radiation were more conductive. The concentration of SO2 and NO2 also appeared to have significant effect on the emergence of nucleation events but because of the great amount of missing observations, we had to exclude them from the final analysis.

  8. Survival analysis using S analysis of time-to-event data

    CERN Document Server

    Tableman, Mara

    2003-01-01

    Survival Analysis Using S: Analysis of Time-to-Event Data is designed as a text for a one-semester or one-quarter course in survival analysis for upper-level or graduate students in statistics, biostatistics, and epidemiology. Prerequisites are a standard pre-calculus first course in probability and statistics, and a course in applied linear regression models. No prior knowledge of S or R is assumed. A wide choice of exercises is included, some intended for more advanced students with a first course in mathematical statistics. The authors emphasize parametric log-linear models, while also detailing nonparametric procedures along with model building and data diagnostics. Medical and public health researchers will find the discussion of cut point analysis with bootstrap validation, competing risks and the cumulative incidence estimator, and the analysis of left-truncated and right-censored data invaluable. The bootstrap procedure checks robustness of cut point analysis and determines cut point(s). In a chapter ...

  9. Event tree analysis using artificial intelligence techniques

    International Nuclear Information System (INIS)

    Dixon, B.W.; Hinton, M.F.

    1985-01-01

    Artificial Intelligence (AI) techniques used in Expert Systems and Object Oriented Programming are discussed as they apply to Event Tree Analysis. A SeQUence IMPortance calculator, SQUIMP, is presented to demonstrate the implementation of these techniques. Benefits of using AI methods include ease of programming, efficiency of execution, and flexibility of application. The importance of an appropriate user interface is stressed. 5 figs

  10. Verification of Large State/Event Systems using Compositionality and Dependency Analysis

    DEFF Research Database (Denmark)

    Lind-Nielsen, Jørn; Andersen, Henrik Reif; Hulgaard, Henrik

    2001-01-01

    A state/event model is a concurrent version of Mealy machines used for describing embedded reactive systems. This paper introduces a technique that uses compositionality and dependency analysis to significantly improve the efficiency of symbolic model checking of state/event models. It makes...

  11. Verification of Large State/Event Systems using Compositionality and Dependency Analysis

    DEFF Research Database (Denmark)

    Lind-Nielsen, Jørn; Andersen, Henrik Reif; Behrmann, Gerd

    1999-01-01

    A state/event model is a concurrent version of Mealy machines used for describing embedded reactive systems. This paper introduces a technique that uses \\emph{compositionality} and \\emph{dependency analysis} to significantly improve the efficiency of symbolic model checking of state/event models...

  12. Performance Analysis: Work Control Events Identified January - August 2010

    Energy Technology Data Exchange (ETDEWEB)

    De Grange, C E; Freeman, J W; Kerr, C E; Holman, G; Marsh, K; Beach, R

    2011-01-14

    This performance analysis evaluated 24 events that occurred at LLNL from January through August 2010. The analysis identified areas of potential work control process and/or implementation weaknesses and several common underlying causes. Human performance improvement and safety culture factors were part of the causal analysis of each event and were analyzed. The collective significance of all events in 2010, as measured by the occurrence reporting significance category and by the proportion of events that have been reported to the DOE ORPS under the ''management concerns'' reporting criteria, does not appear to have increased in 2010. The frequency of reporting in each of the significance categories has not changed in 2010 compared to the previous four years. There is no change indicating a trend in the significance category and there has been no increase in the proportion of occurrences reported in the higher significance category. Also, the frequency of events, 42 events reported through August 2010, is not greater than in previous years and is below the average of 63 occurrences per year at LLNL since 2006. Over the previous four years, an average of 43% of the LLNL's reported occurrences have been reported as either ''management concerns'' or ''near misses.'' In 2010, 29% of the occurrences have been reported as ''management concerns'' or ''near misses.'' This rate indicates that LLNL is now reporting fewer ''management concern'' and ''near miss'' occurrences compared to the previous four years. From 2008 to the present, LLNL senior management has undertaken a series of initiatives to strengthen the work planning and control system with the primary objective to improve worker safety. In 2008, the LLNL Deputy Director established the Work Control Integrated Project Team to develop the core requirements and graded

  13. Using additional external inputs to forecast water quality with an artificial neural network for contamination event detection in source water

    Science.gov (United States)

    Schmidt, F.; Liu, S.

    2016-12-01

    Source water quality plays an important role for the safety of drinking water and early detection of its contamination is vital to taking appropriate countermeasures. However, compared to drinking water, it is more difficult to detect contamination events because its environment is less controlled and numerous natural causes contribute to a high variability of the background values. In this project, Artificial Neural Networks (ANNs) and a Contamination Event Detection Process (CED Process) were used to identify events in river water. The ANN models the response of basic water quality sensors obtained in laboratory experiments in an off-line learning stage and continuously forecasts future values of the time line in an on-line forecasting step. During this second stage, the CED Process compares the forecast to the measured value and classifies it as regular background or event value, which modifies the ANN's continuous learning and influences its forecasts. In addition to this basic setup, external information is fed to the CED Process: A so-called Operator Input (OI) is provided to inform about unusual water quality levels that are unrelated to the presence of contamination, for example due to cooling water discharge from a nearby power plant. This study's primary goal is to evaluate how well the OI fits into the design of the combined forecasting ANN and CED Process and to understand its effects on the online forecasting stage. To test this, data from laboratory experiments conducted previously at the School of Environment, Tsinghua University, have been used to perform simulations highlighting features and drawbacks of this method. Applying the OI has been shown to have a positive influence on the ANN's ability to handle a sudden change in background values, which is unrelated to contamination. However, it might also mask the presence of an event, an issue that underlines the necessity to have several instances of the algorithm run in parallel. Other difficulties

  14. Apical External Root Resorption and Repair in Orthodontic Tooth Movement: Biological Events

    OpenAIRE

    Feller, Liviu; Khammissa, Razia A. G.; Thomadakis, George; Fourie, Jeanine; Lemmer, Johan

    2016-01-01

    Some degree of external root resorption is a frequent, unpredictable, and unavoidable consequence of orthodontic tooth movement mediated by odontoclasts/cementoclasts originating from circulating precursor cells in the periodontal ligament. Its pathogenesis involves mechanical forces initiating complex interactions between signalling pathways activated by various biological agents. Resorption of cementum is regulated by mechanisms similar to those controlling osteoclastogenesis and bone resor...

  15. ExternE: Externalities of energy Vol. 5. Nuclear

    International Nuclear Information System (INIS)

    Dreicer, M.; Tort, V.; Manen, P.

    1995-01-01

    in the cases of electricity generation and transportation, where accidental situations are evaluated. The impacts of construction and decommissioning of a facility are included in the electricity generation stage. It is important to stress that this methodology does not employ a worst case scenario analysis, as is usually done for safety or regulatory compliance assessments, but intends to evaluate the impacts expected from the operations. In a few cases, however, when no reasonable alternative seemed possible, conservative values were used. The impact pathway approach requires an inventory and assessment of all potential impacts, however, within the context of the ExternE project it has not been possible to consider all of these. Therefore, only the most important impacts, called priority impacts, have been included. Releases of radioactive material to the environment, which potentially impact public health, were given the highest priority. Occupational health impacts, from both radiological and nonradiological causes, were the next priority, even though the extent to which occupational health impacts can be considered as externalities has not yet been addressed

  16. Ultimate design load analysis of planetary gearbox bearings under extreme events

    DEFF Research Database (Denmark)

    Gallego Calderon, Juan Felipe; Natarajan, Anand; Cutululis, Nicolaos Antonio

    2017-01-01

    This paper investigates the impact of extreme events on the planet bearings of a 5 MW gearbox. The system is simulated using an aeroelastic tool, where the turbine structure is modeled, and MATLAB/Simulink, where the drivetrain (gearbox and generator) are modeled using a lumped-parameter approach....... Three extreme events are assessed: low-voltage ride through, emergency stop and normal stop. The analysis is focused on finding which event has the most negative impact on the bearing extreme radial loads. The two latter events are carried out following the guidelines of the International...

  17. An uncertainty analysis of air pollution externalities from road transport in Belgium in 2010.

    Science.gov (United States)

    Int Panis, L; De Nocker, L; Cornelis, E; Torfs, R

    2004-12-01

    Although stricter standards for vehicles will reduce emissions to air significantly by 2010, a number of problems will remain, especially related to particulate concentrations in cities, ground-level ozone, and CO(2). To evaluate the impacts of new policy measures, tools need to be available that assess the potential benefits of these measures in terms of the vehicle fleet, fuel choice, modal choice, kilometers driven, emissions, and the impacts on public health and related external costs. The ExternE accounting framework offers the most up to date and comprehensive methodology to assess marginal external costs of energy-related pollutants. It combines emission models, air dispersion models at local and regional scales with dose-response functions and valuation rules. Vito has extended this accounting framework with data and models related to the future composition of the vehicle fleet and transportation demand to evaluate the impact of new policy proposals on air quality and aggregated (total) external costs by 2010. Special attention was given to uncertainty analysis. The uncertainty for more than 100 different parameters was combined in Monte Carlo simulations to assess the range of possible outcomes and the main drivers of these results. Although the impacts from emission standards and total fleet mileage look dominant at first, a number of other factors were found to be important as well. This includes the number of diesel vehicles, inspection and maintenance (high-emitter cars), use of air conditioning, and heavy duty transit traffic.

  18. An uncertainty analysis of air pollution externalities from road transport in Belgium in 2010

    International Nuclear Information System (INIS)

    Int Panis, L.; De Nocker, L.; Cornelis, E.; Torfs, R.

    2004-01-01

    Although stricter standards for vehicles will reduce emissions to air significantly by 2010, a number of problems will remain, especially related to particulate concentrations in cities, ground-level ozone, and CO 2 . To evaluate the impacts of new policy measures, tools need to be available that assess the potential benefits of these measures in terms of the vehicle fleet, fuel choice, modal choice, kilometers driven, emissions, and the impacts on public health and related external costs. The ExternE accounting framework offers the most up to date and comprehensive methodology to assess marginal external costs of energy-related pollutants. It combines emission models, air dispersion models at local and regional scales with dose-response functions and valuation rules. Vito has extended this accounting framework with data and models related to the future composition of the vehicle fleet and transportation demand to evaluate the impact of new policy proposals on air quality and aggregated (total) external costs by 2010. Special attention was given to uncertainty analysis. The uncertainty for more than 100 different parameters was combined in Monte Carlo simulations to assess the range of possible outcomes and the main drivers of these results. Although the impacts from emission standards and total fleet mileage look dominant at first, a number of other factors were found to be important as well. This includes the number of diesel vehicles, inspection and maintenance (high-emitter cars), use of air conditioning, and heavy duty transit traffic

  19. 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.

  20. Analysis of unprotected overcooling events in the Integral Fast Reactor

    International Nuclear Information System (INIS)

    Vilim, R.B.

    1989-01-01

    Simple analytic models are developed for predicting the response of a metal fueled, liquid-metal cooled reactor to unprotected overcooling events in the balance of plant. All overcooling initiators are shown to fall into two categories. The first category contains these events for which there is no final equilibrium state of constant overcooling, as in the case for a large steam leak. These events are analyzed using a non-flow control mass approach. The second category contains those events which will eventually equilibrate, such as a loss of feedwater heaters. A steady flow control volume analysis shows that these latter events ultimately affect the plant through the feedwater inlet to the steam generator. The models developed for analyzing these two categories provide upper bounds for the reactor's passive response to overcooling accident initiators. Calculation of these bounds for a prototypic plant indicate that failure limits -- eutectic melting, sodium boiling, fuel pin failure -- are not exceeded in any overcooling event. 2 refs

  1. Microprocessor event analysis in parallel with CAMAC data acquisition

    CERN Document Server

    Cords, D; Riege, H

    1981-01-01

    The Plessey MIPROC-16 microprocessor (16 bits, 250 ns execution time) has been connected to a CAMAC System (GEC-ELLIOTT System Crate) and shares the CAMAC access with a Nord-10S computer. Interfaces have been designed and tested for execution of CAMAC cycles, communication with the Nord-10S computer and DMA-transfer from CAMAC to the MIPROC-16 memory. The system is used in the JADE data-acquisition-system at PETRA where it receives the data from the detector in parallel with the Nord-10S computer via DMA through the indirect-data-channel mode. The microprocessor performs an on-line analysis of events and the results of various checks is appended to the event. In case of spurious triggers or clear beam gas events, the Nord-10S buffer will be reset and the event omitted from further processing. (5 refs).

  2. The effectiveness of external sensory cues in improving functional performance in individuals with Parkinson's disease: a systematic review with meta-analysis.

    Science.gov (United States)

    Cassimatis, Constantine; Liu, Karen P Y; Fahey, Paul; Bissett, Michelle

    2016-09-01

    A systematic review with meta-analysis was performed to investigate the effect external sensory cued therapy on activities of daily living (ADL) performance that include walking and daily tasks such as dressing for individuals with Parkinson's disease (PD). A detailed computer-aided search of the literature was applied to MEDLINE, Cumulative Index to Nursing and Allied Health Literature, EMBASE and PubMed. Studies investigating the effects of external sensory cued therapy on ADL performance for individuals with PD in all stages of disease progression were collected. Relevant articles were critically reviewed and study results were synthesized by two independent researchers. A data-analysis method was used to extract data from selected articles. A meta-analysis was carried out for all randomized-controlled trials. Six studies with 243 individuals with PD were included in this review. All six studies yielded positive findings in favour of external sensory cues. The meta-analysis showed that external sensory cued therapy improved statistically after treatment (P=0.011) and at follow-up (Psensory into a training programme focused on improving daily task performance.

  3. Energy policy and externalities

    International Nuclear Information System (INIS)

    Bertel, E.; Fraser, P.

    2002-01-01

    External costs of energy have been assessed in a number of authoritative and reliable studies based upon widely accepted methodologies such as life cycle analysis (LCA). However, although those costs are recognised by most stakeholders and decision makers, results from analytical work on externalities and LCA studies are seldom used in policy making. The International Energy Agency (IEA) and the Nuclear Energy Agency (NEA) convened a joint workshop in November 2001 to offer experts and policy makers an opportunity to present state-of-the-art results from analytical work on externalities and debate issues related to the relevance of external costs and LCA for policy-making purposes. The findings from the workshop highlight the need for further work in the field and the potential rote of international organisations like the IEA and the NEA in this context. (authors)

  4. Collective action on the western range: coping with external and internal threats

    Directory of Open Access Journals (Sweden)

    Abigail M. York

    2011-09-01

    Full Text Available Collaborative natural resource management institutions enable agents with diverse interests to come together to solve complex problems. These actors must overcome a series of collective action problems to create, maintain, and evolve these institutions. In addition to the challenge of heterogeneous actors, these commons social-ecological systems often face internal and external threats or disturbances. The institutional arrangements may be effective with problems that are internal to a social-ecological system – ones that they are designed to handle, but how do these arrangements cope with external disturbances, especially ones caused by large-scale political and economic decisions, events, and processes. Using ethnographic and archival data we conduct an institutional analysis outlining the existing and emerging collaboratives, the important actors, and ongoing efforts to cope with the five major challenges identified by rangeland actors. We trace the evolution of institutions on the western range with a focus on their ability to cope with challenges that are largely within the system – biodiversity, fire, and water management, and those that are driven externally by actors who are largely absent – border militarization and violence and exurbanization.

  5. Regression analysis of mixed panel count data with dependent terminal events.

    Science.gov (United States)

    Yu, Guanglei; Zhu, Liang; Li, Yang; Sun, Jianguo; Robison, Leslie L

    2017-05-10

    Event history studies are commonly conducted in many fields, and a great deal of literature has been established for the analysis of the two types of data commonly arising from these studies: recurrent event data and panel count data. The former arises if all study subjects are followed continuously, while the latter means that each study subject is observed only at discrete time points. In reality, a third type of data, a mixture of the two types of the data earlier, may occur and furthermore, as with the first two types of the data, there may exist a dependent terminal event, which may preclude the occurrences of recurrent events of interest. This paper discusses regression analysis of mixed recurrent event and panel count data in the presence of a terminal event and an estimating equation-based approach is proposed for estimation of regression parameters of interest. In addition, the asymptotic properties of the proposed estimator are established, and a simulation study conducted to assess the finite-sample performance of the proposed method suggests that it works well in practical situations. Finally, the methodology is applied to a childhood cancer study that motivated this study. Copyright © 2017 John Wiley & Sons, Ltd. Copyright © 2017 John Wiley & Sons, Ltd.

  6. Mode of delivery after successful external cephalic version: a systematic review and meta-analysis

    NARCIS (Netherlands)

    de Hundt, Marcella; Velzel, Joost; de Groot, Christianne J.; Mol, Ben W.; Kok, Marjolein

    2014-01-01

    To assess the mode of delivery in women after a successful external cephalic version by performing a systematic review and meta-analysis. We searched MEDLINE, Embase, ClinicalTrials.gov, Cumulative Index to Nursing and Allied Health Literature, and the Cochrane Library for studies reporting on the

  7. ANALYSIS OF HYGROTHERMAL CONDITIONS OF EXTERNAL PARTITIONS IN AN UNDERGROUND FRUIT STORE

    Directory of Open Access Journals (Sweden)

    Grzegorz Nawalany

    2016-09-01

    Full Text Available The paper presents the analysis of hygrothermal conditions of external partitions in an underground fruit store. The results of measurements of temperature and humidity of the indoor and outdoor air as well as the surface surrounding temperature and the temperature of the air surrounding the store constituted the boundary conditions for the hygrothermal calculations. The paper presents the calculation of the distribution of the temperature and humidity on the ground floor, the wall contacting the ground, the wall contacting the outside air, and the ceiling above the storage chamber. The heat and moisture calculations have shown high risk of condensation submerged in non-insulated external walls. The condition of the adaptation of a traditional cold store to a simple and atmosphere controlled cold one is to increase the thermal resistance of the partitions. Such a solution will let cut the energy demand in those types of agricultural buildings.

  8. Balboa: A Framework for Event-Based Process Data Analysis

    National Research Council Canada - National Science Library

    Cook, Jonathan E; Wolf, Alexander L

    1998-01-01

    .... We have built Balboa as a bridge between the data collection and the analysis tools, facilitating the gathering and management of event data, and simplifying the construction of tools to analyze the data...

  9. Stability analysis of an open shallow cylindrical shell with imperfection under external pressure

    Directory of Open Access Journals (Sweden)

    Psotny Martin

    2017-01-01

    Full Text Available Elastic shallow generalized cylindrical shells of an open cross-section subjected to the various forms of external pressure are analysed in the paper numerically using the finite element method. Load - displacement paths are calculated for the perfect and imperfect geometry, respectively. Special attention is paid to the influence of initial geometric imperfection on the limit load level of fundamental equilibrium path of nonlinear analysis. ANSYS system was used for analysis, arc-length method was chosen for obtaining fundamental load - displacement path of solution.

  10. Arenal-type pyroclastic flows: A probabilistic event tree risk analysis

    Science.gov (United States)

    Meloy, Anthony F.

    2006-09-01

    A quantitative hazard-specific scenario-modelling risk analysis is performed at Arenal volcano, Costa Rica for the newly recognised Arenal-type pyroclastic flow (ATPF) phenomenon using an event tree framework. These flows are generated by the sudden depressurisation and fragmentation of an active basaltic andesite lava pool as a result of a partial collapse of the crater wall. The deposits of this type of flow include angular blocks and juvenile clasts, which are rarely found in other types of pyroclastic flow. An event tree analysis (ETA) is a useful tool and framework in which to analyse and graphically present the probabilities of the occurrence of many possible events in a complex system. Four event trees are created in the analysis, three of which are extended to investigate the varying individual risk faced by three generic representatives of the surrounding community: a resident, a worker, and a tourist. The raw numerical risk estimates determined by the ETA are converted into a set of linguistic expressions (i.e. VERY HIGH, HIGH, MODERATE etc.) using an established risk classification scale. Three individually tailored semi-quantitative risk maps are then created from a set of risk conversion tables to show how the risk varies for each individual in different areas around the volcano. In some cases, by relocating from the north to the south, the level of risk can be reduced by up to three classes. While the individual risk maps may be broadly applicable, and therefore of interest to the general community, the risk maps and associated probability values generated in the ETA are intended to be used by trained professionals and government agencies to evaluate the risk and effectively manage the long-term development of infrastructure and habitation. With the addition of fresh monitoring data, the combination of both long- and short-term event trees would provide a comprehensive and consistent method of risk analysis (both during and pre-crisis), and as such

  11. 3D FE Analysis of RC Beams Externally Strengthened with SRG/SRP Systems

    Directory of Open Access Journals (Sweden)

    Francesco Bencardino

    2016-05-01

    Full Text Available The purpose of this study is to evaluate, through a nonlinear Finite Element (FE analysis, the structural behavior of Reinforced Concrete (RC beams externally strengthened by using Steel Reinforced Grout (SRG and Steel Reinforced Polymer (SRP systems. The parameters taken into account were the external strengthening configuration, with or without U-wrap end anchorages, as well as the strengthening materials. The numerical simulations were carried out by using a three-dimensional (3D FE model. The linear and nonlinear behavior of all materials was modeled by appropriate constitutive laws and the connection between concrete substrate and external reinforcing layer was simulated by means of cohesive surfaces with appropriate bond-slip laws. In order to overcome convergence difficulties, to simulate the quasi-static response of the strengthened RC beams, a dynamic approach was adopted. The numerical results in terms of load-displacement curves, failure modes, and load and strain values at critical stages were validated against some experimental data. As a result, the proposed 3D FE model can be used to predict the structural behavior up to ultimate stage of similar strengthened beams without carrying out experimental tests.

  12. Markov chains and semi-Markov models in time-to-event analysis.

    Science.gov (United States)

    Abner, Erin L; Charnigo, Richard J; Kryscio, Richard J

    2013-10-25

    A variety of statistical methods are available to investigators for analysis of time-to-event data, often referred to as survival analysis. Kaplan-Meier estimation and Cox proportional hazards regression are commonly employed tools but are not appropriate for all studies, particularly in the presence of competing risks and when multiple or recurrent outcomes are of interest. Markov chain models can accommodate censored data, competing risks (informative censoring), multiple outcomes, recurrent outcomes, frailty, and non-constant survival probabilities. Markov chain models, though often overlooked by investigators in time-to-event analysis, have long been used in clinical studies and have widespread application in other fields.

  13. Food recognition and recipe analysis: integrating visual content, context and external knowledge

    OpenAIRE

    Herranz, Luis; Min, Weiqing; Jiang, Shuqiang

    2018-01-01

    The central role of food in our individual and social life, combined with recent technological advances, has motivated a growing interest in applications that help to better monitor dietary habits as well as the exploration and retrieval of food-related information. We review how visual content, context and external knowledge can be integrated effectively into food-oriented applications, with special focus on recipe analysis and retrieval, food recommendation, and the restaurant context as em...

  14. Development and Commissioning of an External Beam Facility in the Union College Ion Beam Analysis Laboratory

    Science.gov (United States)

    Yoskowitz, Joshua; Clark, Morgan; Labrake, Scott; Vineyard, Michael

    2015-10-01

    We have developed an external beam facility for the 1.1-MV tandem Pelletron accelerator in the Union College Ion Beam Analysis Laboratory. The beam is extracted from an aluminum pipe through a 1 / 4 ' ' diameter window with a 7.5- μm thick Kapton foil. This external beam facility allows us to perform ion beam analysis on samples that cannot be put under vacuum, including wet samples and samples too large to fit into the scattering chamber. We have commissioned the new facility by performing proton induced X-ray emission (PIXE) analysis of several samples of environmental interest. These include samples of artificial turf, running tracks, and a human tooth with an amalgam filling. A 1.7-MeV external proton beam was incident on the samples positioned 2 cm from the window. The resulting X-rays were measured using a silicon drift detector and were analyzed using GUPIX software to determine the concentrations of elements in the samples. The results on the human tooth indicate that while significant concentrations of Hg, Ag, and Sn are present in the amalgam filling, only trace amounts of Hg appear to have leached into the tooth. The artificial turf and running tracks show rather large concentrations of a broad range of elements and trace amounts of Pb in the turf infill.

  15. Event-by-Event Continuous Respiratory Motion Correction for Dynamic PET Imaging.

    Science.gov (United States)

    Yu, Yunhan; Chan, Chung; Ma, Tianyu; Liu, Yaqiang; Gallezot, Jean-Dominique; Naganawa, Mika; Kelada, Olivia J; Germino, Mary; Sinusas, Albert J; Carson, Richard E; Liu, Chi

    2016-07-01

    Existing respiratory motion-correction methods are applied only to static PET imaging. We have previously developed an event-by-event respiratory motion-correction method with correlations between internal organ motion and external respiratory signals (INTEX). This method is uniquely appropriate for dynamic imaging because it corrects motion for each time point. In this study, we applied INTEX to human dynamic PET studies with various tracers and investigated the impact on kinetic parameter estimation. The use of 3 tracers-a myocardial perfusion tracer, (82)Rb (n = 7); a pancreatic β-cell tracer, (18)F-FP(+)DTBZ (n = 4); and a tumor hypoxia tracer, (18)F-fluoromisonidazole ((18)F-FMISO) (n = 1)-was investigated in a study of 12 human subjects. Both rest and stress studies were performed for (82)Rb. The Anzai belt system was used to record respiratory motion. Three-dimensional internal organ motion in high temporal resolution was calculated by INTEX to guide event-by-event respiratory motion correction of target organs in each dynamic frame. Time-activity curves of regions of interest drawn based on end-expiration PET images were obtained. For (82)Rb studies, K1 was obtained with a 1-tissue model using a left-ventricle input function. Rest-stress myocardial blood flow (MBF) and coronary flow reserve (CFR) were determined. For (18)F-FP(+)DTBZ studies, the total volume of distribution was estimated with arterial input functions using the multilinear analysis 1 method. For the (18)F-FMISO study, the net uptake rate Ki was obtained with a 2-tissue irreversible model using a left-ventricle input function. All parameters were compared with the values derived without motion correction. With INTEX, K1 and MBF increased by 10% ± 12% and 15% ± 19%, respectively, for (82)Rb stress studies. CFR increased by 19% ± 21%. For studies with motion amplitudes greater than 8 mm (n = 3), K1, MBF, and CFR increased by 20% ± 12%, 30% ± 20%, and 34% ± 23%, respectively. For (82)Rb

  16. Top event prevention analysis - a deterministic use of PRA

    International Nuclear Information System (INIS)

    Blanchard, D.P.; Worrell, R.B.

    1995-01-01

    Risk importance measures are popular for many applications of probabilistic analysis. Inherent in the derivation of risk importance measures are implicit assumptions that those using these numerical results should be aware of in their decision making. These assumptions and potential limitations include the following: (1) The risk importance measures are derived for a single event at a time and are therefore valid only if all other event probabilities are unchanged at their current values. (2) The results for which risk importance measures are derived may not be complete for reasons such as truncation

  17. Use of external cost assessment and multi-criteria decision analysis for comparative evaluation of options for electricity supply

    International Nuclear Information System (INIS)

    Hirschberg, Stefan; Dones, Roberto; Gantner, Urs

    2000-01-01

    This paper addresses external cost and multi-criteria analyses carried out for selected future electricity generating systems of interest under the Swiss. conditions. The external cost estimates are based on an application of the 'impact pathway approach', enriched by earlier experience from extensive Life Cycle Assessment (LCA). The estimated total costs, i.e. the sum of internal and external costs may serve as a measure of economic and environmental efficiency of energy systems. The multi-criteria approach allows a more explicit consideration of the social dimension, highly important for the decision process. The applications of multi-criteria analysis illustrate the sensitivity of the results to a range of preferences expressed in the energy debate. Certain patterns in systems ranking can be observed in spite of these sensitivities. Both total cost assessment and multi-criteria analysis are found to be useful, complementary instruments to support the decision process. (author)

  18. Development of Quantitative Framework for Event Significance Evaluation

    International Nuclear Information System (INIS)

    Lee, Durk Hun; Kim, Min Chull; Kim, Inn Seock

    2010-01-01

    There is an increasing trend in quantitative evaluation of the safety significance of operational events using Probabilistic Safety Assessment (PSA) technique. An integrated framework for evaluation of event significance has been developed by Korea Institute of Nuclear Safety (KINS), which consists of an assessment hierarchy and a number of matrices. The safety significance of various events, e.g., internal or external initiating events that occurred during at-power or shutdown conditions, can be quantitatively analyzed using this framework, and then, the events rated according to their significance. This paper briefly describes the basic concept of the integrated quantitative framework for evaluation of event significance, focusing on the assessment hierarchy

  19. Optimized electricity expansions with external costs internalized and risk of severe accidents as a new criterion in the decision analysis

    Energy Technology Data Exchange (ETDEWEB)

    Martin del Campo M, C.; Estrada S, G. J., E-mail: cmcm@fi-b.unam.mx [UNAM, Facultad de Ingenieria, Departamento de Sistemas Energeticos, Paseo Cuauhnahuac 8532, 62550 Jiutepec, Morelos (Mexico)

    2011-11-15

    The external cost of severe accidents was incorporated as a new element for the assessment of energy technologies in the expansion plans of the Mexican electric generating system. Optimizations of the electric expansions were made by internalizing the external cost into the objective function of the WASP-IV model as a variable cost, and these expansions were compared with the expansion plans that did not internalize them. Average external costs reported by the Extern E Project were used for each type of technology and were added to the variable component of operation and maintenance cost in the study cases in which the externalises were internalized. Special attention was paid to study the convenience of including nuclear energy in the generating mix. The comparative assessment of six expansion plans was made by means of the Position Vector of Minimum Regret Analysis (PVMRA) decision analysis tool. The expansion plans were ranked according to seven decision criteria which consider internal costs, economical impact associated with incremental fuel prices, diversity, external costs, foreign capital fraction, carbon-free fraction, and external costs of severe accidents. A set of data for the calculation of the last criterion was obtained from a Report of the European Commission. We found that with the external costs included in the optimization process of WASP-IV, better electric expansion plans, with lower total (internal + external) generating costs, were found. On the other hand, the plans which included the participation of nuclear power plants were in general relatively more attractive than the plans that did not. (Author)

  20. 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)

  1. [Analysis on the adverse events of cupping therapy in the application].

    Science.gov (United States)

    Zhou, Xin; Ruan, Jing-wen; Xing, Bing-feng

    2014-10-01

    The deep analysis has been done on the cases of adverse events and common injury of cupping therapy encountered in recent years in terms of manipulation and patient's constitution. The adverse events of cupping therapy are commonly caused by improper manipulation of medical practitioners, ignoring contraindication and patient's constitution. Clinical practitioners should use cupping therapy cautiously, follow strictly the rules of standard manipulation and medical core system, pay attention to the contraindication and take strict precautions against the occurrence of adverse events.

  2. Multiple Score Comparison: a network meta-analysis approach to comparison and external validation of prognostic scores

    Directory of Open Access Journals (Sweden)

    Sarah R. Haile

    2017-12-01

    Full Text Available Abstract Background Prediction models and prognostic scores have been increasingly popular in both clinical practice and clinical research settings, for example to aid in risk-based decision making or control for confounding. In many medical fields, a large number of prognostic scores are available, but practitioners may find it difficult to choose between them due to lack of external validation as well as lack of comparisons between them. Methods Borrowing methodology from network meta-analysis, we describe an approach to Multiple Score Comparison meta-analysis (MSC which permits concurrent external validation and comparisons of prognostic scores using individual patient data (IPD arising from a large-scale international collaboration. We describe the challenges in adapting network meta-analysis to the MSC setting, for instance the need to explicitly include correlations between the scores on a cohort level, and how to deal with many multi-score studies. We propose first using IPD to make cohort-level aggregate discrimination or calibration scores, comparing all to a common comparator. Then, standard network meta-analysis techniques can be applied, taking care to consider correlation structures in cohorts with multiple scores. Transitivity, consistency and heterogeneity are also examined. Results We provide a clinical application, comparing prognostic scores for 3-year mortality in patients with chronic obstructive pulmonary disease using data from a large-scale collaborative initiative. We focus on the discriminative properties of the prognostic scores. Our results show clear differences in performance, with ADO and eBODE showing higher discrimination with respect to mortality than other considered scores. The assumptions of transitivity and local and global consistency were not violated. Heterogeneity was small. Conclusions We applied a network meta-analytic methodology to externally validate and concurrently compare the prognostic properties

  3. Twitter data analysis: temporal and term frequency analysis with real-time event

    Science.gov (United States)

    Yadav, Garima; Joshi, Mansi; Sasikala, R.

    2017-11-01

    From the past few years, World Wide Web (www) has become a prominent and huge source for user generated content and opinionative data. Among various social media, Twitter gained popularity as it offers a fast and effective way of sharing users’ perspective towards various critical and other issues in different domain. As the data is hugely generated on cloud, it has opened doors for the researchers in the field of data science and analysis. There are various domains such as ‘Political’ domain, ‘Entertainment’ domain and ‘Business’ domain. Also there are various APIs that Twitter provides for developers 1) Search API, focus on the old tweets 2) Rest API, focuses on user details and allow to collect the user profile, friends and followers 3) Streaming API, which collects details like tweets, hashtags, geo locations. In our work we are accessing Streaming API in order to fetch real-time tweets for the dynamic happening event. For this we are focusing on ‘Entertainment’ domain especially ‘Sports’ as IPL-T20 is currently the trending on-going event. We are collecting these numerous amounts of tweets and storing them in MongoDB database where the tweets are stored in JSON document format. On this document we are performing time-series analysis and term frequency analysis using different techniques such as filtering, information extraction for text-mining that fulfils our objective of finding interesting moments for temporal data in the event and finding the ranking among the players or the teams based on popularity which helps people in understanding key influencers on the social media platform.

  4. Environmental external effects from wind power based on the EU ExternE methodology

    DEFF Research Database (Denmark)

    Ibsen, Liselotte Schleisner; Nielsen, Per Sieverts

    1998-01-01

    of the Danish part of the project is to implement the framework for externality evaluation, for three different power plants located in Denmark. The paper will focus on the assessment of the impacts of the whole fuel cycles for wind, natural gas and biogas. Priority areas for environmental impact assessment......The European Commission has launched a major study project, ExternE, to develop a methodology to quantify externalities. A “National Implementation Phase”, was started under the Joule II programme with the purpose of implementing the ExternE methodology in all member states. The main objective...

  5. ExternE National Implementation Finland

    Energy Technology Data Exchange (ETDEWEB)

    Pingoud, K; Maelkki, H; Wihersaari, M; Pirilae, P [VTT Energy, Espoo (Finland); Hongisto, M [Imatran Voima Oy, Vantaa (Finland); Siitonen, S [Ekono Energy Ltd, Espoo (Finland); Johansson, M [Finnish Environment Institute, Helsinki (Finland)

    1999-07-01

    ExternE National Implementation is a continuation of the ExternE Project, funded in part by the European Commission's Joule III Programme. This study is the result of the ExternE National Implementation Project for Finland. Three fuel cycles were selected for the Finnish study: coal, peat and wood-derived biomass, which together are responsible for about 40% of total electricity generation in Finland and about 75% of the non-nuclear fuel based generation. The estimated external costs or damages were dominated by the global warming (GW) impacts in the coal and peat fuel cycles, but knowledge of the true GW impacts is still uncertain. From among other impacts that were valued in monetary terms the human health damages due to airborne emissions dominated in all the three fuel cycles. Monetary valuation for ecosystem impacts is not possible using the ExternE methodology at present. The Meri-Pori power station representing the coal fuel cycle is one of the world's cleanest and most efficient coal-fired power plants with a condensing turbine. The coal is imported mainly from Poland. The estimated health damages were about 4 mECU/kWh, crop damages an order of magnitude lower and damages caused to building materials two orders of magnitude lower. The power stations of the peat and biomass fuel cycles are of CHP type, generating electricity and heat for the district heating systems of two cities. Their fuels are of domestic origin. The estimated health damages allocated to electricity generation were about 5 and 6 mECU/kWh, respectively. The estimates were case-specific and thus an generalisation of the results to the whole electricity generation in Finland is unrealistic. Despite the uncertainties and limitations of the methodology, it is a promising tool in the comparison of similar kinds of fuel cycles, new power plants and pollution abatement technologies and different plant locations with each other. (orig.)

  6. ExternE National Implementation Finland

    Energy Technology Data Exchange (ETDEWEB)

    Pingoud, K.; Maelkki, H.; Wihersaari, M.; Pirilae, P. [VTT Energy, Espoo (Finland); Hongisto, M. [Imatran Voima Oy, Vantaa (Finland); Siitonen, S. [Ekono Energy Ltd, Espoo (Finland); Johansson, M. [Finnish Environment Institute, Helsinki (Finland)

    1999-07-01

    ExternE National Implementation is a continuation of the ExternE Project, funded in part by the European Commission's Joule III Programme. This study is the result of the ExternE National Implementation Project for Finland. Three fuel cycles were selected for the Finnish study: coal, peat and wood-derived biomass, which together are responsible for about 40% of total electricity generation in Finland and about 75% of the non-nuclear fuel based generation. The estimated external costs or damages were dominated by the global warming (GW) impacts in the coal and peat fuel cycles, but knowledge of the true GW impacts is still uncertain. From among other impacts that were valued in monetary terms the human health damages due to airborne emissions dominated in all the three fuel cycles. Monetary valuation for ecosystem impacts is not possible using the ExternE methodology at present. The Meri-Pori power station representing the coal fuel cycle is one of the world's cleanest and most efficient coal-fired power plants with a condensing turbine. The coal is imported mainly from Poland. The estimated health damages were about 4 mECU/kWh, crop damages an order of magnitude lower and damages caused to building materials two orders of magnitude lower. The power stations of the peat and biomass fuel cycles are of CHP type, generating electricity and heat for the district heating systems of two cities. Their fuels are of domestic origin. The estimated health damages allocated to electricity generation were about 5 and 6 mECU/kWh, respectively. The estimates were case-specific and thus an generalisation of the results to the whole electricity generation in Finland is unrealistic. Despite the uncertainties and limitations of the methodology, it is a promising tool in the comparison of similar kinds of fuel cycles, new power plants and pollution abatement technologies and different plant locations with each other. (orig.)

  7. ExternE National Implementation Finland

    International Nuclear Information System (INIS)

    Pingoud, K.; Maelkki, H.; Wihersaari, M.; Pirilae, P.; Hongisto, M.; Siitonen, S.; Johansson, M.

    1999-01-01

    ExternE National Implementation is a continuation of the ExternE Project, funded in part by the European Commission's Joule III Programme. This study is the result of the ExternE National Implementation Project for Finland. Three fuel cycles were selected for the Finnish study: coal, peat and wood-derived biomass, which together are responsible for about 40% of total electricity generation in Finland and about 75% of the non-nuclear fuel based generation. The estimated external costs or damages were dominated by the global warming (GW) impacts in the coal and peat fuel cycles, but knowledge of the true GW impacts is still uncertain. From among other impacts that were valued in monetary terms the human health damages due to airborne emissions dominated in all the three fuel cycles. Monetary valuation for ecosystem impacts is not possible using the ExternE methodology at present. The Meri-Pori power station representing the coal fuel cycle is one of the world's cleanest and most efficient coal-fired power plants with a condensing turbine. The coal is imported mainly from Poland. The estimated health damages were about 4 mECU/kWh, crop damages an order of magnitude lower and damages caused to building materials two orders of magnitude lower. The power stations of the peat and biomass fuel cycles are of CHP type, generating electricity and heat for the district heating systems of two cities. Their fuels are of domestic origin. The estimated health damages allocated to electricity generation were about 5 and 6 mECU/kWh, respectively. The estimates were case-specific and thus an generalisation of the results to the whole electricity generation in Finland is unrealistic. Despite the uncertainties and limitations of the methodology, it is a promising tool in the comparison of similar kinds of fuel cycles, new power plants and pollution abatement technologies and different plant locations with each other. (orig.)

  8. A new external microbeam system in Fudan University

    International Nuclear Information System (INIS)

    Zheng, Y.; Shen, H.; Li, Y.Q.; Li, X.Y.; Yang, M.J.; Mi, Y.

    2013-01-01

    A cost-effective and removable external beam system is set up based on the Oxford Microbeam system in Fudan University. In our external beam system, 7.5-μm-thick Kapton film is used as exit window with a diameter of 3.5 mm. The spatial resolution is about 18 μm full width at half maximum (FWHM) on a copper grid. As an example, calcium distribution in otolith is present by the external micro-PIXE. In addition, little change can be done to the external system mentioned above for radiobiology experiments. The exit window can be changed from the focal plane to the observation window of vacuum chamber. By calculation, the beam spot size can reach less than 30 μm. Since the Oxford type octagonal target chamber is popular among the nuclear microprobe facilities, this method can be provided to easily replace the in-vacuum system with the external system, extending the in-vacuum analysis to external beam analysis

  9. A new external microbeam system in Fudan University

    Energy Technology Data Exchange (ETDEWEB)

    Zheng, Y.; Shen, H., E-mail: haoshen@fudan.edu.cn; Li, Y.Q.; Li, X.Y.; Yang, M.J.; Mi, Y.

    2013-07-01

    A cost-effective and removable external beam system is set up based on the Oxford Microbeam system in Fudan University. In our external beam system, 7.5-μm-thick Kapton film is used as exit window with a diameter of 3.5 mm. The spatial resolution is about 18 μm full width at half maximum (FWHM) on a copper grid. As an example, calcium distribution in otolith is present by the external micro-PIXE. In addition, little change can be done to the external system mentioned above for radiobiology experiments. The exit window can be changed from the focal plane to the observation window of vacuum chamber. By calculation, the beam spot size can reach less than 30 μm. Since the Oxford type octagonal target chamber is popular among the nuclear microprobe facilities, this method can be provided to easily replace the in-vacuum system with the external system, extending the in-vacuum analysis to external beam analysis.

  10. A new external microbeam system in Fudan University

    Energy Technology Data Exchange (ETDEWEB)

    Zheng, Y. [Applied Ion Beam Physics Laboratory, Institute of Modern Physics, Fudan University, Shanghai 200433 (China); Shen, H., E-mail: haoshen@fudan.edu.cn [Applied Ion Beam Physics Laboratory, Institute of Modern Physics, Fudan University, Shanghai 200433 (China); Li, Y.Q.; Li, X.Y.; Yang, M.J.; Mi, Y. [Applied Ion Beam Physics Laboratory, Institute of Modern Physics, Fudan University, Shanghai 200433 (China)

    2013-02-01

    A cost-effective and removable external beam system is set up based on the Oxford Microbeam system in Fudan University. In our external beam system, 7.5-μm-thick Kapton film is used as exit window with a diameter of 3.5 mm. The spatial resolution is about 18 μm full width at half maximum (FWHM) on a copper grid. As an example, calcium distribution in otolith is present by the external micro-PIXE. In addition, little change can be done to the external system mentioned above for radiobiology experiments. The exit window can be changed from the focal plane to the observation window of vacuum chamber. By calculation, the beam spot size can reach less than 30 μm. Since the Oxford type octagonal target chamber is popular among the nuclear microprobe facilities, this method can be provided to easily replace the in-vacuum system with the external system, extending the in-vacuum analysis to external beam analysis.

  11. Analysis hierarchical model for discrete event systems

    Science.gov (United States)

    Ciortea, E. M.

    2015-11-01

    The This paper presents the hierarchical model based on discrete event network for robotic systems. Based on the hierarchical approach, Petri network is analysed as a network of the highest conceptual level and the lowest level of local control. For modelling and control of complex robotic systems using extended Petri nets. Such a system is structured, controlled and analysed in this paper by using Visual Object Net ++ package that is relatively simple and easy to use, and the results are shown as representations easy to interpret. The hierarchical structure of the robotic system is implemented on computers analysed using specialized programs. Implementation of hierarchical model discrete event systems, as a real-time operating system on a computer network connected via a serial bus is possible, where each computer is dedicated to local and Petri model of a subsystem global robotic system. Since Petri models are simplified to apply general computers, analysis, modelling, complex manufacturing systems control can be achieved using Petri nets. Discrete event systems is a pragmatic tool for modelling industrial systems. For system modelling using Petri nets because we have our system where discrete event. To highlight the auxiliary time Petri model using transport stream divided into hierarchical levels and sections are analysed successively. Proposed robotic system simulation using timed Petri, offers the opportunity to view the robotic time. Application of goods or robotic and transmission times obtained by measuring spot is obtained graphics showing the average time for transport activity, using the parameters sets of finished products. individually.

  12. Elemental analysis of artefacts - establishing external beam PIXE

    International Nuclear Information System (INIS)

    Alves, A.; Johnston, P.; Short, R.; Bubb, I.

    1999-01-01

    The development of an external PIXE facility on the 1 MV Tandetron accelerator at RMIT has led to a wide range of research possibilities. A proton beam, generated inside a vacuum is brought into air via an Au coated Kapton foil exit window (thickness 8μm, diameter 0.35mm). Monitoring of the beam intensity is achieved by detecting backscattered protons from the inside Au coating on the window. Artefacts, which may be too large to be placed inside the vacuum, are positioned in the beamline opposite the exit window. An optical system consisting of a CCD camera, alignment laser and two mirrors allows viewing of a region of the target 10mm x 10mm. This technique provides quantitative analysis of elements in the pigments used in paintings and on ceramics, which is a valuable tool in art conservation and authentication. Application of the technique to a ceramic sample from the historic house 'Viewbank' is described

  13. External Dynamics Influencing Tattooing among College Students: A Qualitative Analysis

    Science.gov (United States)

    Firmin, Michael; Tse, Luke; Foster, Janna; Angelini, Tammy

    2012-01-01

    The study utilized qualitative research methodology to assess external dynamics and their influences on tattooing practices among college students. Twenty-four undergraduates supplied in-depth interviews regarding the external variables related to college students' decisions to tattoo. The present research follows (Tse, Firmin, Angelini, &…

  14. Monitoring As A Helpful Means In Forensic Analysis Of Dams Static Instability Events

    Science.gov (United States)

    Solimene, Pellegrino

    2013-04-01

    Monitoring is a means of controlling the behavior of a structure, which during its operational life is subject to external actions as ordinary loading conditions and disturbing ones; these factors overlap with the random manner defined by the statistical parameter of the return period. The analysis of the monitoring data is crucial to gain a reasoned opinion on the reliability of the structure and its components, and also allows to identify, in the overall operational scenario, the time when preparing interventions aimed at maintaining the optimum levels of functionality and safety. The concept of monitoring in terms of prevention is coupled with the activity of Forensic Engineer who, by Judiciary appointment for the occurrence of an accident, turns its experience -the "Scientific knowledge"- in an "inverse analysis" in which he summed up the results of a survey, which also draws on data sets arising in the course of the constant control of the causes and effects, so to determine the correlations between these factors. His activity aims at giving a contribution to the identification of the typicality of an event, which represents, together with "causal link" between the conduct and events and contra-juridical, the factors judging if there an hypothesis of crime, and therefore liable according to law. In Italy there are about 10,000 dams of varying sizes, but only a small portion of them are considered "large dams" and subjected to a rigorous program of regular inspections and monitoring, in application of specific rules. The rest -"small" dams, conventionally defined as such by the standard, but not for the impact on the area- is affected by a heterogeneous response from the local authorities entrusted with this task: there is therefore a high potential risk scenario, as determined by the presence of not completely controlled structures that insist even on areas heavily populated. Risk can be traced back to acceptable levels if they were implemented with the

  15. [Long-term efficacy of open reduction and internal fixation versus external fixation for unstable distal radius fractures: a meta-analysis].

    Science.gov (United States)

    Yang, Z; Yuan, Z Z; Ma, J X; Ma, X L

    2017-11-07

    Objective: To make a systematic assessment of the Long-term efficacy of open reduction and internal fixation versus external fixation for unstable distal radius fractures. Methods: A computer-based online search of PubMed, ScienceDirect, EMBASE, BIOSIS, Springer and Cochrane Library were performed. The randomized and controlled trials of open reduction and internal fixation versus external fixation for unstable distal radius fractures were collected. The included trials were screened out strictly based on the criterion of inclusion and exclusion. The quality of included trials was evaluated. RevMan 5.0 was used for data analysis. Results: Sixteen studies involving 1 268 patients were included. There were 618 patients with open reduction and internal fixation and 650 with external fixation. The results of meta-analysis indicated that there were statistically significant differences with regard to the complications postoperatively (infection( I (2)=0%, RR =0.27, 95% CI 0.16-0.45, Z =4.92, P internal fixation and external fixation are effective treatment for unstable distal radius fractures. Compared with external fixation, open reduction and internal fixation provides reduced complications postoperatively, lower DASH scores and better restoration of volar tilt for treatment of distal radius fractures.

  16. Regional Externalities

    NARCIS (Netherlands)

    Heijman, W.J.M.

    2007-01-01

    The book offers practical and theoretical insights in regional externalities. Regional externalities are a specific subset of externalities that can be defined as externalities where space plays a dominant role. This class of externalities can be divided into three categories: (1) externalities

  17. Elastic extension of a local analysis facility on external clouds for the LHC experiments

    Science.gov (United States)

    Ciaschini, V.; Codispoti, G.; Rinaldi, L.; Aiftimiei, D. C.; Bonacorsi, D.; Calligola, P.; Dal Pra, S.; De Girolamo, D.; Di Maria, R.; Grandi, C.; Michelotto, D.; Panella, M.; Taneja, S.; Semeria, F.

    2017-10-01

    The computing infrastructures serving the LHC experiments have been designed to cope at most with the average amount of data recorded. The usage peaks, as already observed in Run-I, may however originate large backlogs, thus delaying the completion of the data reconstruction and ultimately the data availability for physics analysis. In order to cope with the production peaks, the LHC experiments are exploring the opportunity to access Cloud resources provided by external partners or commercial providers. In this work we present the proof of concept of the elastic extension of a local analysis facility, specifically the Bologna Tier-3 Grid site, for the LHC experiments hosted at the site, on an external OpenStack infrastructure. We focus on the Cloud Bursting of the Grid site using DynFarm, a newly designed tool that allows the dynamic registration of new worker nodes to LSF. In this approach, the dynamically added worker nodes instantiated on an OpenStack infrastructure are transparently accessed by the LHC Grid tools and at the same time they serve as an extension of the farm for the local usage.

  18. Analysis of ancient Indian silver punch-marked coins by external PIXE

    International Nuclear Information System (INIS)

    Rautray, Tapash R.; Nayak, Suman S.; Tripathy, Bipin B.; Das, Saubhagyalaxmi; Das, Manas R.; Das, Satya R.; Chattopadhyay, Pranab K.

    2011-01-01

    Seven silver punch-marked coins were analysed using external particle induced X-ray emission technique. The main group of elements like Ag, Cu, Au, Pb and Fe were estimated along with a number of trace/minor elements such as K, Ca, Ti, V, Cr, Mn, Co, Ni and Rb in the analysed silver coins. Gold was found in all the coins and varied between 0.7% and 6.2% indicating the better economic condition of that civilisation. - Highlights: → The silver punch-marked coins, in the current study, were in use in India between 6th century BC to 6th century AD and have been analysed by in-air PIXE. → These sets of coins have immense archaeological importance because of their very rare availability. → These coins are distinguished from other coins because of the presence of gold as major element. → While the British period coins were fabricated using modern technologies, the punch-marked coins were shaped manually with developed metal technology. → The analysis of punch-marked coins using external PIXE beam has been done for the first time, which is unique of its kind.

  19. Evaluation of Fourier integral. Spectral analysis of seismic events

    International Nuclear Information System (INIS)

    Chitaru, Cristian; Enescu, Dumitru

    2003-01-01

    Spectral analysis of seismic events represents a method for great earthquake prediction. The seismic signal is not a sinusoidal signal; for this, it is necessary to find a method for best approximation of real signal with a sinusoidal signal. The 'Quanterra' broadband station allows the data access in numerical and/or graphical forms. With the numerical form we can easily make a computer program (MSOFFICE-EXCEL) for spectral analysis. (authors)

  20. Analysis of Loss-of-Offsite-Power Events 1997-2015

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, Nancy Ellen [Idaho National Lab. (INL), Idaho Falls, ID (United States); Schroeder, John Alton [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2016-07-01

    Loss of offsite power (LOOP) can have a major negative impact on a power plant’s ability to achieve and maintain safe shutdown conditions. LOOP event frequencies and times required for subsequent restoration of offsite power are important inputs to plant probabilistic risk assessments. This report presents a statistical and engineering analysis of LOOP frequencies and durations at U.S. commercial nuclear power plants. The data used in this study are based on the operating experience during calendar years 1997 through 2015. LOOP events during critical operation that do not result in a reactor trip, are not included. Frequencies and durations were determined for four event categories: plant-centered, switchyard-centered, grid-related, and weather-related. Emergency diesel generator reliability is also considered (failure to start, failure to load and run, and failure to run more than 1 hour). There is an adverse trend in LOOP durations. The previously reported adverse trend in LOOP frequency was not statistically significant for 2006-2015. Grid-related LOOPs happen predominantly in the summer. Switchyard-centered LOOPs happen predominantly in winter and spring. Plant-centered and weather-related LOOPs do not show statistically significant seasonality. The engineering analysis of LOOP data shows that human errors have been much less frequent since 1997 than in the 1986 -1996 time period.

  1. Analysis of surface contributions to external doses in a radioactively contaminated urban environment designed by the EMRAS-2 Urban Areas Working Group

    International Nuclear Information System (INIS)

    Hwang, Won Tae; Jeong, Hae Sun; Jeong, Hyo Joon; Kim, Eun Han; Han, Moon Hee; Kim, In Gyu

    2013-01-01

    Highlights: ► External dose and contribution from radio-activated surface were evaluated for EMRAS-2 Urban Areas Working Group scenarios. ► The external doses showed a distinctive difference with the locations and precipitation. ► The contribution of contaminated surfaces for external dose depends on locations and precipitation. ► These results provide the essential information for decision-making support of countermeasures. - Abstract: The EMRAS-2 Urban Areas Working Group, which is supported by the IAEA, has designed a variety of accidental scenarios to test and improve the capabilities of the models used for an evaluation of radioactive contamination in an urban environment. A variety of models including a Korean model, METRO-K, are used for predictive results on the hypothetical scenarios. This paper describes the predictive results of METRO-K for the hypothetical scenarios designed in the Working Group. The external dose resulting from the air contamination of Co-60 was evaluated, and its contribution was analyzed with time as a function of the location of a receptor and precipitation conditions at the time of the contamination event. As a result, the external doses showed a distinctive difference with the locations to be evaluated and the precipitation conditions. Moreover, the contribution of contaminated surfaces for external doses was strongly dependent on the locations to be evaluated and the precipitation conditions. These results will provide essential information to assist the decision-making of appropriate countermeasures in an emergency situation of a radioactively contaminated urban environment

  2. Pressure Effects Analysis of National Ignition Facility Capacitor Module Events

    International Nuclear Information System (INIS)

    Brereton, S; Ma, C; Newton, M; Pastrnak, J; Price, D; Prokosch, D

    1999-01-01

    Capacitors and power conditioning systems required for the National Ignition Facility (NIF) have experienced several catastrophic failures during prototype demonstration. These events generally resulted in explosion, generating a dramatic fireball and energetic shrapnel, and thus may present a threat to the walls of the capacitor bay that houses the capacitor modules. The purpose of this paper is to evaluate the ability of the capacitor bay walls to withstand the overpressure generated by the aforementioned events. Two calculations are described in this paper. The first one was used to estimate the energy release during a fireball event and the second one was used to estimate the pressure in a capacitor module during a capacitor explosion event. Both results were then used to estimate the subsequent overpressure in the capacitor bay where these events occurred. The analysis showed that the expected capacitor bay overpressure was less than the pressure tolerance of the walls. To understand the risk of the above events in NIF, capacitor module failure probabilities were also calculated. This paper concludes with estimates of the probability of single module failure and multi-module failures based on the number of catastrophic failures in the prototype demonstration facility

  3. Regression analysis of mixed recurrent-event and panel-count data with additive rate models.

    Science.gov (United States)

    Zhu, Liang; Zhao, Hui; Sun, Jianguo; Leisenring, Wendy; Robison, Leslie L

    2015-03-01

    Event-history studies of recurrent events are often conducted in fields such as demography, epidemiology, medicine, and social sciences (Cook and Lawless, 2007, The Statistical Analysis of Recurrent Events. New York: Springer-Verlag; Zhao et al., 2011, Test 20, 1-42). For such analysis, two types of data have been extensively investigated: recurrent-event data and panel-count data. However, in practice, one may face a third type of data, mixed recurrent-event and panel-count data or mixed event-history data. Such data occur if some study subjects are monitored or observed continuously and thus provide recurrent-event data, while the others are observed only at discrete times and hence give only panel-count data. A more general situation is that each subject is observed continuously over certain time periods but only at discrete times over other time periods. There exists little literature on the analysis of such mixed data except that published by Zhu et al. (2013, Statistics in Medicine 32, 1954-1963). In this article, we consider the regression analysis of mixed data using the additive rate model and develop some estimating equation-based approaches to estimate the regression parameters of interest. Both finite sample and asymptotic properties of the resulting estimators are established, and the numerical studies suggest that the proposed methodology works well for practical situations. The approach is applied to a Childhood Cancer Survivor Study that motivated this study. © 2014, The International Biometric Society.

  4. Analysis of the population movement in the Czech Republic through external migration in the period 1993–2003

    Directory of Open Access Journals (Sweden)

    Milan Palát

    2006-01-01

    Full Text Available The paper presents partial findings obtained during the study of external migration according to countries in a defined territorial unit and time period. Applied methodical procedures of the statistical processing of empirical data make possible, in addition to the exact description of the proportion of selected country groups and aggregated particular countries on the total number of immigrants, emigrants and derived values of migration increases or decreases, also the description of developmental trends of the analysed time series of assessed events and point short-term extrapolation prediction.

  5. Influence of Manufacturing Methods of Implant-Supported Crowns on External and Internal Marginal Fit: A Micro-CT Analysis.

    Science.gov (United States)

    Moris, Izabela C M; Monteiro, Silas Borges; Martins, Raíssa; Ribeiro, Ricardo Faria; Gomes, Erica A

    2018-01-01

    To evaluate the influence of different manufacturing methods of single implant-supported metallic crowns on the internal and external marginal fit through computed microtomography. Forty external hexagon implants were divided into 4 groups ( n = 8), according to the manufacturing method: GC, conventional casting; GI, induction casting; GP, plasma casting; and GCAD, CAD/CAM machining. The crowns were attached to the implants with insertion torque of 30 N·cm. The external (vertical and horizontal) marginal fit and internal fit were assessed through computed microtomography. Internal and external marginal fit data ( μ m) were submitted to a one-way ANOVA and Tukey's test ( α = .05). Qualitative evaluation of the images was conducted by using micro-CT. The statistical analysis revealed no significant difference between the groups for vertical misfit ( P = 0.721). There was no significant difference ( P > 0.05) for the internal and horizontal marginal misfit in the groups GC, GI, and GP, but it was found for the group GCAD ( P ≤ 0.05). Qualitative analysis revealed that most of the samples of cast groups exhibited crowns underextension while the group GCAD showed overextension. The manufacturing method of the crowns influenced the accuracy of marginal fit between the prosthesis and implant. The best results were found for the crowns fabricated through CAD/CAM machining.

  6. Urbanization and fertility: an event-history analysis of coastal Ghana.

    Science.gov (United States)

    White, Michael J; Muhidin, Salut; Andrzejewski, Catherine; Tagoe, Eva; Knight, Rodney; Reed, Holly

    2008-11-01

    In this article, we undertake an event-history analysis of fertility in Ghana. We exploit detailed life history calendar data to conduct a more refined and definitive analysis of the relationship among personal traits, urban residence, and fertility. Although urbanization is generally associated with lower fertility in developing countries, inferences in most studies have been hampered by a lack of information about the timing of residence in relationship to childbearing. We find that the effect of urbanization itself is strong, evident, and complex, and persists after we control for the effects of age, cohort, union status, and education. Our discrete-time event-history analysis shows that urban women exhibit fertility rates that are, on average, 11% lower than those of rural women, but the effects vary by parity. Differences in urban population traits would augment the effects of urban adaptation itself Extensions of the analysis point to the operation of a selection effect in rural-to-urban mobility but provide limited evidence for disruption effects. The possibility of further selection of urbanward migrants on unmeasured traits remains. The analysis also demonstrates the utility of an annual life history calendar for collecting such data in the field.

  7. External costs related to power production technologies. ExternE national implementation for Denmark

    Energy Technology Data Exchange (ETDEWEB)

    Schleisner, L; Sieverts Nielsen, P [eds.

    1997-12-01

    The objective of the ExternE National Implementation project has been to establish a comprehensive and comparable set of data on externalities of power generation for all EU member states and Norway. The tasks include the application of the ExternE methodology to the most important fuel cycles for each country as well as to update the already existing results, to aggregate these site- and technology-specific results to more general figures. The current report covers the detailed information concerning the ExternE methodology. Importance is attached to the computer system used in the project and the assessment of air pollution effects on health, materials and ecological effects. Also the assessment of global warming damages are described. Finally the report covers the detailed information concerning the national implementation for Denmark for an offshore wind farm and a wind farm on land, a decentralised CHP plant based on natural gas and a decentralised CHP plant base on biogas. (au) EU-JOULE 3. 79 tabs., 11 ills., 201 refs.

  8. External costs related to power production technologies. ExternE national implementation for Denmark

    International Nuclear Information System (INIS)

    Schleisner, L.; Sieverts Nielsen, P.

    1997-12-01

    The objective of the ExternE National Implementation project has been to establish a comprehensive and comparable set of data on externalities of power generation for all EU member states and Norway. The tasks include the application of the ExternE methodology to the most important fuel cycles for each country as well as to update the already existing results, to aggregate these site- and technology-specific results to more general figures. The current report covers the detailed information concerning the ExternE methodology. Importance is attached to the computer system used in the project and the assessment of air pollution effects on health, materials and ecological effects. Also the assessment of global warming damages are described. Finally the report covers the detailed information concerning the national implementation for Denmark for an offshore wind farm and a wind farm on land, a decentralised CHP plant based on natural gas and a decentralised CHP plant base on biogas. (au) EU-JOULE 3. 79 tabs., 11 ills., 201 refs

  9. On the relativistic particle dynamics in external gravitational fields

    International Nuclear Information System (INIS)

    Kuz'menkov, L.S.; Naumov, N.D.

    1977-01-01

    On the base of the Riemann metrics of an event space, leading to the Newton mechanics at nonrelativistic velocities and not obligatory weak gravitational fields relativistic particle dynamics in external gravitation fields has been considered. Found are trajectories, motion laws and light ray equations for the homogeneous and Newton fields

  10. An analysis of critical heat flux on the external surface of the reactor vessel lower head

    International Nuclear Information System (INIS)

    Yang, Soo Hyung; Baek, Won Pil; Chang, Soon Heung

    1999-01-01

    CHF (Critical heat flux) on the external surface of the reactor vessel lower head is major key in the evaluation on the feasibility of IVR-EVC (In-Vessel Retention through External Vessel Cooling) concept. To identify the CHF on the external surface, considerable works have been performed. Through the review on the previous works related to the CHF on the external surface, liquid subcooling, induced flow along the external surface, ICI (In-Core Instrument) nozzle and minimum gap are identified as major parameters. According to the present analysis, the effects of the ICI nozzle and minimum gap on CHF are pronounced at the upstream of test vessel: on the other hand, the induced flow considerably affects the CHF at downstream of test vessel. In addition, the subcooling effect is shown at all of test vessel, and decreases with the increase in the elevation of test vessel. In the real application of the IVR-EVC concept, vertical position is known as a limiting position, at which thermal margin is the minimum. So, it is very important to precisely predict the CHF at vertical position in a viewpoint of gaining more thermal margins. However, the effects of the liquid subcooling and induced flow do not seem to be adequately included in the CHF correlations suggested by previous works, especially at the downstream positions

  11. Review of the Oconee-3 probabilistic risk assessment: external events, core damage frequency. Volume 2

    Energy Technology Data Exchange (ETDEWEB)

    Hanan, N.A.; Ilberg, D.; Xue, D.; Youngblood, R.; Reed, J.W.; McCann, M.; Talwani, T.; Wreathall, J.; Kurth, P.D.; Bandyopadhyay, K.

    1986-03-01

    A review of the Oconee-3 Probabilistic Risk Assessment (OPRA) was conducted with the broad objective of evaluating qualitatively and quantitatively (as much as possible) the OPRA assessment of the important sequences that are ''externally'' generated and lead to core damage. The review included a technical assessment of the assumptions and methods used in the OPRA within its stated objective and with the limited information available. Within this scope, BNL performed a detailed reevaluation of the accident sequences generated by internal floods and earthquakes and a less detailed review (in some cases a scoping review) for the accident sequences generated by fires, tornadoes, external floods, and aircraft impact. 12 refs., 24 figs., 31 tabs.

  12. Review of the Oconee-3 probabilistic risk assessment: external events, core damage frequency. Volume 2

    International Nuclear Information System (INIS)

    Hanan, N.A.; Ilberg, D.; Xue, D.

    1986-03-01

    A review of the Oconee-3 Probabilistic Risk Assessment (OPRA) was conducted with the broad objective of evaluating qualitatively and quantitatively (as much as possible) the OPRA assessment of the important sequences that are ''externally'' generated and lead to core damage. The review included a technical assessment of the assumptions and methods used in the OPRA within its stated objective and with the limited information available. Within this scope, BNL performed a detailed reevaluation of the accident sequences generated by internal floods and earthquakes and a less detailed review (in some cases a scoping review) for the accident sequences generated by fires, tornadoes, external floods, and aircraft impact. 12 refs., 24 figs., 31 tabs

  13. Study of the peculiarities of multiparticle production via event-by-event analysis in asymmetric nucleus-nucleus interactions

    Science.gov (United States)

    Fedosimova, Anastasiya; Gaitinov, Adigam; Grushevskaya, Ekaterina; Lebedev, Igor

    2017-06-01

    In this work the study on the peculiarities of multiparticle production in interactions of asymmetric nuclei to search for unusual features of such interactions, is performed. A research of long-range and short-range multiparticle correlations in the pseudorapidity distribution of secondary particles on the basis of analysis of individual interactions of nuclei of 197 Au at energy 10.7 AGeV with photoemulsion nuclei, is carried out. Events with long-range multiparticle correlations (LC), short-range multiparticle correlations (SC) and mixed type (MT) in pseudorapidity distribution of secondary particles, are selected by the Hurst method in accordance with Hurst curve behavior. These types have significantly different characteristics. At first, they have different fragmentation parameters. Events of LC type are processes of full destruction of the projectile nucleus, in which multicharge fragments are absent. In events of mixed type several multicharge fragments of projectile nucleus are discovered. Secondly, these two types have significantly different multiplicity distribution. The mean multiplicity of LC type events is significantly more than in mixed type events. On the basis of research of the dependence of multiplicity versus target-nuclei fragments number for events of various types it is revealed, that the most considerable multiparticle correlations are observed in interactions of the mixed type, which correspond to the central collisions of gold nuclei and nuclei of CNO-group, i.e. nuclei with strongly asymmetric volume, nuclear mass, charge, etc. Such events are characterised by full destruction of the target-nucleus and the disintegration of the projectile-nucleus on several multi-charged fragments.

  14. Study of the peculiarities of multiparticle production via event-by-event analysis in asymmetric nucleus-nucleus interactions

    Directory of Open Access Journals (Sweden)

    Fedosimova Anastasiya

    2017-01-01

    Full Text Available In this work the study on the peculiarities of multiparticle production in interactions of asymmetric nuclei to search for unusual features of such interactions, is performed. A research of long-range and short-range multiparticle correlations in the pseudorapidity distribution of secondary particles on the basis of analysis of individual interactions of nuclei of 197 Au at energy 10.7 AGeV with photoemulsion nuclei, is carried out. Events with long-range multiparticle correlations (LC, short-range multiparticle correlations (SC and mixed type (MT in pseudorapidity distribution of secondary particles, are selected by the Hurst method in accordance with Hurst curve behavior. These types have significantly different characteristics. At first, they have different fragmentation parameters. Events of LC type are processes of full destruction of the projectile nucleus, in which multicharge fragments are absent. In events of mixed type several multicharge fragments of projectile nucleus are discovered. Secondly, these two types have significantly different multiplicity distribution. The mean multiplicity of LC type events is significantly more than in mixed type events. On the basis of research of the dependence of multiplicity versus target-nuclei fragments number for events of various types it is revealed, that the most considerable multiparticle correlations are observed in interactions of the mixed type, which correspond to the central collisions of gold nuclei and nuclei of CNO-group, i.e. nuclei with strongly asymmetric volume, nuclear mass, charge, etc. Such events are characterised by full destruction of the target-nucleus and the disintegration of the projectile-nucleus on several multi-charged fragments.

  15. Identification of Common Cause Initiating Events Using the NEA IRS Database. Rev 0

    International Nuclear Information System (INIS)

    Kulig, Maciej; Tomic, Bojan; Nyman, R alph

    2007-02-01

    The study presented in this report is a continuation of work conducted for SKI in 1998 on the identification of Common Cause Initiators (CCIs) based on operational events documented in the NEA Incident Reporting System (IRS). Based on the new operational experience accumulated in IRS in the period 1995-2006, the project focused on the identification of new CCI events. An attempt was also made to compare the observations made in the earlier study with the results of the current work. The earlier study and the current project cover the events reported in the IRS database with the incident date in the period from 01.01.1980 to 15.11.2006. The review of the NEA IRS database conducted within this project generated a sample of events that provides insights regarding the Common Cause Initiators (CCIs). This list includes certain number of 'real' CCIs but also potential CCIs and other events that provide insights on potential dependency mechanisms. Relevant characteristics of the events were analysed in the context of CCIs. This evaluation was intended to investigate the importance of the CCI issue and also to provide technical insights that could help in the modelling the CCIs in PSAs. The analysis of operational events provided useful engineering insights regarding the potential dependencies that may originate CCIs. Some indications were also obtained on the plant SSCs/areas that are susceptible to common cause failures. Direct interrelations between the accident mitigation systems through common support systems, which can originate a CCI, represent a dominant dependency mechanism involved in the CCI events. The most important contributors of this type are electrical power supply systems and I-and-C systems. Area-related events (fire, flood, water spray), external hazards (lightning, high wind or cold weather) and transients (water hammer, electrical transients both internal and external) have also been found to be important sources of dependency that may originate CCIs

  16. Identification of Common Cause Initiating Events Using the NEA IRS Database. Rev 0

    Energy Technology Data Exchange (ETDEWEB)

    Kulig, Maciej; Tomic, Bojan (Enconet Consulting, Vienna (Austria)); Nyman, Ralph (Swedish Nuclear Power Inspectorate, Stockholm (Sweden))

    2007-02-15

    The study presented in this report is a continuation of work conducted for SKI in 1998 on the identification of Common Cause Initiators (CCIs) based on operational events documented in the NEA Incident Reporting System (IRS). Based on the new operational experience accumulated in IRS in the period 1995-2006, the project focused on the identification of new CCI events. An attempt was also made to compare the observations made in the earlier study with the results of the current work. The earlier study and the current project cover the events reported in the IRS database with the incident date in the period from 01.01.1980 to 15.11.2006. The review of the NEA IRS database conducted within this project generated a sample of events that provides insights regarding the Common Cause Initiators (CCIs). This list includes certain number of 'real' CCIs but also potential CCIs and other events that provide insights on potential dependency mechanisms. Relevant characteristics of the events were analysed in the context of CCIs. This evaluation was intended to investigate the importance of the CCI issue and also to provide technical insights that could help in the modelling the CCIs in PSAs. The analysis of operational events provided useful engineering insights regarding the potential dependencies that may originate CCIs. Some indications were also obtained on the plant SSCs/areas that are susceptible to common cause failures. Direct interrelations between the accident mitigation systems through common support systems, which can originate a CCI, represent a dominant dependency mechanism involved in the CCI events. The most important contributors of this type are electrical power supply systems and I-and-C systems. Area-related events (fire, flood, water spray), external hazards (lightning, high wind or cold weather) and transients (water hammer, electrical transients both internal and external) have also been found to be important sources of dependency that may

  17. The Advanced Photon Source event system

    International Nuclear Information System (INIS)

    Lenkszus, F.R.; Laird, R.

    1995-01-01

    The Advanced Photon Source, like many other facilities, requires a means of transmitting timing information to distributed control system 1/0 controllers. The APS event system provides the means of distributing medium resolution/accuracy timing events throughout the facility. It consists of VME event generators and event receivers which are interconnected with 10OMbit/sec fiber optic links at distances of up to 650m in either a star or a daisy chain configuration. The systems event throughput rate is 1OMevents/sec with a peak-to-peak timing jitter down to lOOns depending on the source of the event. It is integrated into the EPICS-based A.PS control system through record and device support. Event generators broadcast timing events over fiber optic links to event receivers which are programmed to decode specific events. Event generators generate events in response to external inputs, from internal programmable event sequence RAMS, and from VME bus writes. The event receivers can be programmed to generate both pulse and set/reset level outputs to synchronize hardware, and to generate interrupts to initiate EPICS record processing. In addition, each event receiver contains a time stamp counter which is used to provide synchronized time stamps to EPICS records

  18. Failure analysis and shock protection of external hard disk drive ...

    African Journals Online (AJOL)

    Technology for processing and storage of data in portable external storage hard disks has increasingly improved over the years. Currently, terabytes of data can be stored in one portable external storage hard disk drive. Storing such amount of data on a single disk on itself is a risk. Several instances of data lost by big ...

  19. Immobilization in External Rotation Versus Internal Rotation After Primary Anterior Shoulder Dislocation: A Meta-analysis of Randomized Controlled Trials.

    Science.gov (United States)

    Whelan, Daniel B; Kletke, Stephanie N; Schemitsch, Geoffrey; Chahal, Jaskarndip

    2016-02-01

    The recurrence rate after primary anterior shoulder dislocation is high, especially in young, active individuals. Recent studies have suggested external rotation immobilization as a method to reduce the rate of recurrent shoulder dislocation in comparison to traditional sling immobilization. To assess and summarize evidence from randomized controlled trials on the effect of internal rotation versus external rotation immobilization on the rate of recurrence after primary anterior shoulder dislocation. Meta-analysis. PubMed, MEDLINE, EMBASE, the Cochrane Central Register of Controlled Trials, and abstracts from recent proceedings were searched for eligible studies. Two reviewers selected studies for inclusion, assessed methodological quality, and extracted data. Six randomized controlled trials (632 patients) were included in this review. Demographic and prognostic variables measured at baseline were similar in the pooled groups. The average age was 30.1 years in the pooled external rotation group and 30.3 years in the pooled internal rotation group. Two studies found that external rotation immobilization reduced the rate of recurrence after initial anterior shoulder dislocation compared with conventional internal rotation immobilization, whereas 4 studies failed to find a significant difference between the 2 groups. This meta-analysis suggested no overall significant difference in the rate of recurrence among patients treated with internal rotation versus external rotation immobilization (risk ratio, 0.69; 95% CI, 0.42-1.14; P = .15). There was no significant difference in the rate of compliance between internal and external rotation immobilization (P = .43). The Western Ontario Shoulder Instability Index scores were pooled across 3 studies, and there was no significant difference between the 2 groups (P = .54). Immobilization in external rotation is not significantly more effective in reducing the recurrence rate after primary anterior shoulder dislocation than

  20. Idaho National Laboratory Quarterly Event Performance Analysis FY 2013 4th Quarter

    Energy Technology Data Exchange (ETDEWEB)

    Mitchell, Lisbeth A. [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2013-11-01

    This report is published quarterly by the Idaho National Laboratory (INL) Performance Assurance Organization. The Department of Energy Occurrence Reporting and Processing System (ORPS) as prescribed in DOE Order 232.2 “Occurrence Reporting and Processing of Operations Information” requires a quarterly analysis of events, both reportable and not reportable for the previous twelve months. This report is the analysis of occurrence reports and deficiency reports (including not reportable events) identified at the Idaho National Laboratory (INL) during the period of October 2012 through September 2013.

  1. Normalization Strategies for Enhancing Spatio-Temporal Analysis of Social Media Responses during Extreme Events: A Case Study based on Analysis of Four Extreme Events using Socio-Environmental Data Explorer (SEDE

    Directory of Open Access Journals (Sweden)

    J. Ajayakumar

    2017-10-01

    Full Text Available With social media becoming increasingly location-based, there has been a greater push from researchers across various domains including social science, public health, and disaster management, to tap in the spatial, temporal, and textual data available from these sources to analyze public response during extreme events such as an epidemic outbreak or a natural disaster. Studies based on demographics and other socio-economic factors suggests that social media data could be highly skewed based on the variations of population density with respect to place. To capture the spatio-temporal variations in public response during extreme events we have developed the Socio-Environmental Data Explorer (SEDE. SEDE collects and integrates social media, news and environmental data to support exploration and assessment of public response to extreme events. For this study, using SEDE, we conduct spatio-temporal social media response analysis on four major extreme events in the United States including the “North American storm complex” in December 2015, the “snowstorm Jonas” in January 2016, the “West Virginia floods” in June 2016, and the “Hurricane Matthew” in October 2016. Analysis is conducted on geo-tagged social media data from Twitter and warnings from the storm events database provided by National Centers For Environmental Information (NCEI for analysis. Results demonstrate that, to support complex social media analyses, spatial and population-based normalization and filtering is necessary. The implications of these results suggests that, while developing software solutions to support analysis of non-conventional data sources such as social media, it is quintessential to identify the inherent biases associated with the data sources, and adapt techniques and enhance capabilities to mitigate the bias. The normalization strategies that we have developed and incorporated to SEDE will be helpful in reducing the population bias associated with

  2. Normalization Strategies for Enhancing Spatio-Temporal Analysis of Social Media Responses during Extreme Events: A Case Study based on Analysis of Four Extreme Events using Socio-Environmental Data Explorer (SEDE)

    Science.gov (United States)

    Ajayakumar, J.; Shook, E.; Turner, V. K.

    2017-10-01

    With social media becoming increasingly location-based, there has been a greater push from researchers across various domains including social science, public health, and disaster management, to tap in the spatial, temporal, and textual data available from these sources to analyze public response during extreme events such as an epidemic outbreak or a natural disaster. Studies based on demographics and other socio-economic factors suggests that social media data could be highly skewed based on the variations of population density with respect to place. To capture the spatio-temporal variations in public response during extreme events we have developed the Socio-Environmental Data Explorer (SEDE). SEDE collects and integrates social media, news and environmental data to support exploration and assessment of public response to extreme events. For this study, using SEDE, we conduct spatio-temporal social media response analysis on four major extreme events in the United States including the "North American storm complex" in December 2015, the "snowstorm Jonas" in January 2016, the "West Virginia floods" in June 2016, and the "Hurricane Matthew" in October 2016. Analysis is conducted on geo-tagged social media data from Twitter and warnings from the storm events database provided by National Centers For Environmental Information (NCEI) for analysis. Results demonstrate that, to support complex social media analyses, spatial and population-based normalization and filtering is necessary. The implications of these results suggests that, while developing software solutions to support analysis of non-conventional data sources such as social media, it is quintessential to identify the inherent biases associated with the data sources, and adapt techniques and enhance capabilities to mitigate the bias. The normalization strategies that we have developed and incorporated to SEDE will be helpful in reducing the population bias associated with social media data and will be useful

  3. A risk-informed framework for establishing a beyond design basis safety basis for external hazards

    Energy Technology Data Exchange (ETDEWEB)

    Amico, P. [Hughes Associates, Inc, Baltimore, MD (United States); Anoba, R. [Hughes Associates, Inc, Raleigh, NC (United States); Najafi, B. [Hughes Associates, Inc., Los Gatos, CA (United States)

    2014-07-01

    The events at Fukushima Daiichi taught us that meeting a deterministic design basis requirement for external hazards does not assure that the risk is low. As observed at the plant, the two primary reasons for this are failure cliffs above the design basis event and that combined hazard effects are not considered in design. Because the possible combinations of design basis exceedences and external hazard combinations are very large and complex, an approach focusing only on the most important ones is needed. For this reason, a risk informed approach is the most effective approach, which is discussed in this paper. (author)

  4. Experimental study of single event burnout and single event gate rupture in power MOSFETs and IGBT

    International Nuclear Information System (INIS)

    Tang Benqi; Wang Yanping; Geng Bin

    2001-01-01

    An experimental study was carried out to determine the single event burnout and single event gate rupture sensitivities in power MOSFETs and IGBT which were exposed to heavy ions from 252 Cf source. The test method, test results, a description of observed burnout current waveforms and a discussion of a possible failure mechanism were presented. Current measurements have been performed with a specially designed circuit. The test results include the observed dependence upon applied drain or gate to source bias and versus with external capacitors and limited resistors

  5. Disruptive Event Biosphere Dose Conversion Factor Analysis

    Energy Technology Data Exchange (ETDEWEB)

    M. A. Wasiolek

    2003-07-21

    This analysis report, ''Disruptive Event Biosphere Dose Conversion Factor Analysis'', is one of the technical reports containing documentation of the ERMYN (Environmental Radiation Model for Yucca Mountain Nevada) biosphere model for the geologic repository at Yucca Mountain, its input parameters, and the application of the model to perform the dose assessment for the repository. The biosphere model is one of a series of process models supporting the Total System Performance Assessment (TSPA) for the Yucca Mountain repository. A graphical representation of the documentation hierarchy for the ERMYN is presented in Figure 1-1. This figure shows the interrelationships among the products (i.e., analysis and model reports) developed for biosphere modeling and provides an understanding of how this analysis report contributes to biosphere modeling. This report is one of the two reports that develop biosphere dose conversion factors (BDCFs), which are input parameters for the TSPA model. The ''Biosphere Model Report'' (BSC 2003 [DIRS 164186]) describes in detail the conceptual model as well as the mathematical model and lists its input parameters. Model input parameters are developed and described in detail in five analysis report (BSC 2003 [DIRS 160964], BSC 2003 [DIRS 160965], BSC 2003 [DIRS 160976], BSC 2003 [DIRS 161239], and BSC 2003 [DIRS 161241]). The objective of this analysis was to develop the BDCFs for the volcanic ash exposure scenario and the dose factors (DFs) for calculating inhalation doses during volcanic eruption (eruption phase of the volcanic event). The volcanic ash exposure scenario is hereafter referred to as the volcanic ash scenario. For the volcanic ash scenario, the mode of radionuclide release into the biosphere is a volcanic eruption through the repository with the resulting entrainment of contaminated waste in the tephra and the subsequent atmospheric transport and dispersion of contaminated material in

  6. Disruptive Event Biosphere Dose Conversion Factor Analysis

    International Nuclear Information System (INIS)

    M. A. Wasiolek

    2003-01-01

    This analysis report, ''Disruptive Event Biosphere Dose Conversion Factor Analysis'', is one of the technical reports containing documentation of the ERMYN (Environmental Radiation Model for Yucca Mountain Nevada) biosphere model for the geologic repository at Yucca Mountain, its input parameters, and the application of the model to perform the dose assessment for the repository. The biosphere model is one of a series of process models supporting the Total System Performance Assessment (TSPA) for the Yucca Mountain repository. A graphical representation of the documentation hierarchy for the ERMYN is presented in Figure 1-1. This figure shows the interrelationships among the products (i.e., analysis and model reports) developed for biosphere modeling and provides an understanding of how this analysis report contributes to biosphere modeling. This report is one of the two reports that develop biosphere dose conversion factors (BDCFs), which are input parameters for the TSPA model. The ''Biosphere Model Report'' (BSC 2003 [DIRS 164186]) describes in detail the conceptual model as well as the mathematical model and lists its input parameters. Model input parameters are developed and described in detail in five analysis report (BSC 2003 [DIRS 160964], BSC 2003 [DIRS 160965], BSC 2003 [DIRS 160976], BSC 2003 [DIRS 161239], and BSC 2003 [DIRS 161241]). The objective of this analysis was to develop the BDCFs for the volcanic ash exposure scenario and the dose factors (DFs) for calculating inhalation doses during volcanic eruption (eruption phase of the volcanic event). The volcanic ash exposure scenario is hereafter referred to as the volcanic ash scenario. For the volcanic ash scenario, the mode of radionuclide release into the biosphere is a volcanic eruption through the repository with the resulting entrainment of contaminated waste in the tephra and the subsequent atmospheric transport and dispersion of contaminated material in the biosphere. The biosphere process

  7. The Importance of External Contacts in Job Performance: A Study in Healthcare Organizations Using Social Network Analysis

    Directory of Open Access Journals (Sweden)

    Pilar Marqués-Sánchez

    2018-06-01

    Full Text Available There is evidence that relations between physicians and nurses within healthcare institutions might be shaped by informal aspects of such relations and by links to people external to the organization, with an impact on work performance. Social network analysis is underutilized in exploring such associations. The paper aims to describe physicians’ and nurses’ relationships outside their clinical units and to explore what kind of ties are related to job performance. A network analysis was performed on cross-sectional data. The study population consisted of 196 healthcare employees working in a public hospital and a primary healthcare centre in Spain. Relational data were analysed using the UCINET software package. Measures included: (i sample characteristics; (ii social network variables; and (iii team performance ratings. Descriptive statistics (means, medians, percentages were used to characterize staff and performance ratings. A correlational analysis was conducted to examine the strength of relationships between four different types of ties. Our findings suggest that external ties only contribute to improving the performance of physicians at both the individual and team level. They are focused on the decision-making process about the therapeutic plan and, therefore, might need to seek advice outside the workplace. In contrast, external ties are not relevant for the work performance of nurses, as they need to find solutions to immediate problems in a short period of time, having strong ties in the workplace. Social network analysis can illuminate relations within healthcare organizations and inform the development of innovative interventions.

  8. The Main Concept Analysis in Cantonese Aphasic Oral Discourse: External Validation and Monitoring Chronic Aphasia

    Science.gov (United States)

    Kong, Anthony Pak-Hin

    2011-01-01

    Purpose: The 1st aim of this study was to further establish the external validity of the main concept (MC) analysis by examining its relationship with the Cantonese Linguistic Communication Measure (CLCM; Kong, 2006; Kong & Law, 2004)--an established quantitative system for narrative production--and the Cantonese version of the Western Aphasia…

  9. Identification of fire modeling issues based on an analysis of real events from the OECD FIRE database

    Energy Technology Data Exchange (ETDEWEB)

    Hermann, Dominik [Swiss Federal Nuclear Safety Inspectorate ENSI, Brugg (Switzerland)

    2017-03-15

    Precursor analysis is widely used in the nuclear industry to judge the significance of events relevant to safety. However, in case of events that may damage equipment through effects that are not ordinary functional dependencies, the analysis may not always fully appreciate the potential for further evolution of the event. For fires, which are one class of such events, this paper discusses modelling challenges that need to be overcome when performing a probabilistic precursor analysis. The events used to analyze are selected from the Organisation for Economic Cooperation and Development (OECD) Fire Incidents Records Exchange (FIRE) Database.

  10. Recent and active tectonics of the external zone of the Northern Apennines (Italy)

    Science.gov (United States)

    Boccaletti, Mario; Corti, Giacomo; Martelli, Luca

    2011-08-01

    We present a comprehensive study of the recent and active tectonics of the external part of the Northern Apennines (Italy) by using morphotectonic, geological-structural, and stratigraphic analysis, compared with the current seismicity of the region. This analysis suggests that the external part of the Northern Apennines is characterised by presence of three major systems of Quaternary compressive structures corresponding to (1) the Apenninic watershed, (2) the Apennines-Po Plain margin (pede-Apenninic thrust front), and (3) the Emilia, Ferrara, and Adriatic Fold systems buried below the Po Plain. Geological data and interpreted seismic sections indicate a roughly N-S Quaternary deformation direction, with rates <2.5 mm/year. The shortening decreased since the Pliocene, when our data indicate compression in a NNW-SSE direction and rates up to 7 mm/year. The trend and kinematics of the structures affecting the Apennines-Po Plain margin and the Po Plain subsoil fit well the pattern of the current seismicity of the area, as well as recent GPS and geodetic levelling data, pointing to a current activity of these thrust systems controlled by an overall compressive stress field. Close to the Apenninic watershed, earthquake focal mechanisms indicate that shallow extension is associated to deep compression. The extensional events may be related to a secondary extensional stress field developing on the hangingwall of the thrust system affecting the Apenninic watershed; alternatively, this thrust system may have been recently deactivated and overprinted by active normal faulting. Deeper compressive events are related to the activity of both a major basement thrust that connects at surface with the pede-Apenninic thrust front and a major Moho structure.

  11. Antipsychotics, glycemic disorders, and life-threatening diabetic events: a Bayesian data-mining analysis of the FDA adverse event reporting system (1968-2004).

    Science.gov (United States)

    DuMouchel, William; Fram, David; Yang, Xionghu; Mahmoud, Ramy A; Grogg, Amy L; Engelhart, Luella; Ramaswamy, Krishnan

    2008-01-01

    This analysis compared diabetes-related adverse events associated with use of different antipsychotic agents. A disproportionality analysis of the US Food and Drug Administration (FDA) Adverse Event Reporting System (AERS) was performed. Data from the FDA postmarketing AERS database (1968 through first quarter 2004) were evaluated. Drugs studied included aripiprazole, clozapine, haloperidol, olanzapine, quetiapine, risperidone, and ziprasidone. Fourteen Medical Dictionary for Regulatory Activities (MedDRA) Primary Terms (MPTs) were chosen to identify diabetes-related adverse events; 3 groupings into higher-level descriptive categories were also studied. Three methods of measuring drug-event associations were used: proportional reporting ratio, the empirical Bayes data-mining algorithm known as the Multi-Item Gamma Poisson Shrinker, and logistic regression (LR) analysis. Quantitative measures of association strength, with corresponding confidence intervals, between drugs and specified adverse events were computed and graphed. Some of the LR analyses were repeated separately for reports from patients under and over 45 years of age. Differences in association strength were declared statistically significant if the corresponding 90% confidence intervals did not overlap. Association with various glycemic events differed for different drugs. On average, the rankings of association strength agreed with the following ordering: low association, ziprasidone, aripiprazole, haloperidol, and risperidone; medium association, quetiapine; and strong association, clozapine and olanzapine. The median rank correlation between the above ordering and the 17 sets of LR coefficients (1 set for each glycemic event) was 93%. Many of the disproportionality measures were significantly different across drugs, and ratios of disproportionality factors of 5 or more were frequently observed. There are consistent and substantial differences between atypical antipsychotic drugs in the

  12. Influence of Manufacturing Methods of Implant-Supported Crowns on External and Internal Marginal Fit: A Micro-CT Analysis

    Directory of Open Access Journals (Sweden)

    Izabela C. M. Moris

    2018-01-01

    Full Text Available Aim. To evaluate the influence of different manufacturing methods of single implant-supported metallic crowns on the internal and external marginal fit through computed microtomography. Methods. Forty external hexagon implants were divided into 4 groups (n=8, according to the manufacturing method: GC, conventional casting; GI, induction casting; GP, plasma casting; and GCAD, CAD/CAM machining. The crowns were attached to the implants with insertion torque of 30 N·cm. The external (vertical and horizontal marginal fit and internal fit were assessed through computed microtomography. Internal and external marginal fit data (μm were submitted to a one-way ANOVA and Tukey’s test (α=.05. Qualitative evaluation of the images was conducted by using micro-CT. Results. The statistical analysis revealed no significant difference between the groups for vertical misfit (P=0.721. There was no significant difference (P>0.05 for the internal and horizontal marginal misfit in the groups GC, GI, and GP, but it was found for the group GCAD (P≤0.05. Qualitative analysis revealed that most of the samples of cast groups exhibited crowns underextension while the group GCAD showed overextension. Conclusions. The manufacturing method of the crowns influenced the accuracy of marginal fit between the prosthesis and implant. The best results were found for the crowns fabricated through CAD/CAM machining.

  13. Accidents and incidents with external and/or internal radiation-exposure

    International Nuclear Information System (INIS)

    Anon.

    1990-01-01

    An individual radiation exposure accident is an unexpected and unintended event which gives rise to an overexposure (external or internal). By overexposure one means all external or internal exposure which could lead to the exceeding of the regulatory norms. Going beyond these limits does not always produce pathological manifestations. The term radiological accident is, in practice, used only when there is an occurrence of some biological or clinical response, or when some therapeutic action is required. A radio-exposure accident can occur: within or from a nuclear power plant or from a center employing ionizing radiation. These are the most frequent; and during the transport of radioactive materials. These are exceptional events. The tanks and containers used in the transport of highly radioactive substances are exhaustively studied for their resistance to accidents, and the conditions of transport determined by very strict national and international regulations. The transport of substances of low radioactivity (labelled molecules, radiopharmaceuticals...) carries only minor risks

  14. Magnesium and the Risk of Cardiovascular Events: A Meta-Analysis of Prospective Cohort Studies

    Science.gov (United States)

    Hao, Yongqiang; Li, Huiwu; Tang, Tingting; Wang, Hao; Yan, Weili; Dai, Kerong

    2013-01-01

    Background Prospective studies that have examined the association between dietary magnesium intake and serum magnesium concentrations and the risk of cardiovascular disease (CVD) events have reported conflicting findings. We undertook a meta-analysis to evaluate the association between dietary magnesium intake and serum magnesium concentrations and the risk of total CVD events. Methodology/Principal Findings We performed systematic searches on MEDLINE, EMBASE, and OVID up to February 1, 2012 without limits. Categorical, linear, and nonlinear, dose-response, heterogeneity, publication bias, subgroup, and meta-regression analysis were performed. The analysis included 532,979 participants from 19 studies (11 studies on dietary magnesium intake, 6 studies on serum magnesium concentrations, and 2 studies on both) with 19,926 CVD events. The pooled relative risks of total CVD events for the highest vs. lowest category of dietary magnesium intake and serum magnesium concentrations were 0.85 (95% confidence interval 0.78 to 0.92) and 0.77 (0.66 to 0.87), respectively. In linear dose-response analysis, only serum magnesium concentrations ranging from 1.44 to 1.8 mEq/L were significantly associated with total CVD events risk (0.91, 0.85 to 0.97) per 0.1 mEq/L (Pnonlinearity = 0.465). However, significant inverse associations emerged in nonlinear models for dietary magnesium intake (Pnonlinearity = 0.024). The greatest risk reduction occurred when intake increased from 150 to 400 mg/d. There was no evidence of publication bias. Conclusions/Significance There is a statistically significant nonlinear inverse association between dietary magnesium intake and total CVD events risk. Serum magnesium concentrations are linearly and inversely associated with the risk of total CVD events. PMID:23520480

  15. Experience of steam generator tube examination in the hot laboratory of EDF: analysis of recent events concerning the secondary side

    International Nuclear Information System (INIS)

    Thebault, Y.; Bouvier, O. de; Boccanfuso, M.; Coquio, N.; Barbe, V.; Molinie, E.

    2011-01-01

    Until 2010, more than 60 steam generator (SG) tubes have been removed and analysed in the EDF hot laboratory of CEIDRE/Chinon. This article is particularly related to three recent events that lead to the extraction of several tubes dedicated to laboratory destructive examinations. The first event that constitutes a first occurrence on the EDF Park, concerns the detection of a circumferential crack on the external surface of a tube located at tube support plate elevation. After this observation, several tubes have been extracted from Bugey 3 and Fessenheim 2 nuclear power plants with steam generators equipped with 600 MA bundle. The other two events concern the consequences of chemical cleaning of the tube bundle steam generators. The examples chosen are from Cruas 4 et Chinon B2 units whose tubes were extracted following non destructive testing performed immediately after or at the completion of cycle following the chemical cleaning. In the case of Cruas 4, Eddy Current Testing (ET) were performed for requalification of steam Generators after chemical cleaning. They allowed the detection of an indication located at the bottom of tube for a large number of tubes; the ET signal was similar to that corresponding to 'deposit' corrosion. Moreover, inspections of Chinon-B2 SGs at the end of the operation cycle following the chemical cleaning, showed the presence of conductor deposits at the bottom of some tubes. The first part of this document presents the major results of laboratory examinations of the pulled tubes of Bugey 3 and Fessenheim 2 and their analysis. Hypothesis concerning damage mechanisms of the tubes are also proposed. The second part of the paper relates the results of the laboratory examinations of the pulled tubes of Cruas 4 and Chinon B 2 after chemical cleaning and their analysis. (authors)

  16. 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

  17. Analysis of stress concentration in the Dutton groove regions of the Super Lightweight External Tank

    Science.gov (United States)

    Ahmed, R.

    1995-05-01

    Because the 2195 aluminum-lithium material of the super lightweight external tank (SLWT ET) has a lower toughness than the 2219 aluminum used in previous ET's, careful attention must be paid to stress concentrations. This report details the analysis performed on some of the stress concentrations in the orthogrid panels of the liquid hydrogen tank.

  18. Probabilistic Dynamics for Integrated Analysis of Accident Sequences considering Uncertain Events

    Directory of Open Access Journals (Sweden)

    Robertas Alzbutas

    2015-01-01

    Full Text Available The analytical/deterministic modelling and simulation/probabilistic methods are used separately as a rule in order to analyse the physical processes and random or uncertain events. However, in the currently used probabilistic safety assessment this is an issue. The lack of treatment of dynamic interactions between the physical processes on one hand and random events on the other hand causes the limited assessment. In general, there are a lot of mathematical modelling theories, which can be used separately or integrated in order to extend possibilities of modelling and analysis. The Theory of Probabilistic Dynamics (TPD and its augmented version based on the concept of stimulus and delay are introduced for the dynamic reliability modelling and the simulation of accidents in hybrid (continuous-discrete systems considering uncertain events. An approach of non-Markovian simulation and uncertainty analysis is discussed in order to adapt the Stimulus-Driven TPD for practical applications. The developed approach and related methods are used as a basis for a test case simulation in view of various methods applications for severe accident scenario simulation and uncertainty analysis. For this and for wider analysis of accident sequences the initial test case specification is then extended and discussed. Finally, it is concluded that enhancing the modelling of stimulated dynamics with uncertainty and sensitivity analysis allows the detailed simulation of complex system characteristics and representation of their uncertainty. The developed approach of accident modelling and analysis can be efficiently used to estimate the reliability of hybrid systems and at the same time to analyze and possibly decrease the uncertainty of this estimate.

  19. Trend analysis of human error events and assessment of their proactive prevention measure at Rokkasho reprocessing plant

    International Nuclear Information System (INIS)

    Yamazaki, Satoru; Tanaka, Izumi; Wakabayashi, Toshio

    2012-01-01

    A trend analysis of human error events is important for preventing the recurrence of human error events. We propose a new method for identifying the common characteristics from results of trend analysis, such as the latent weakness of organization, and a management process for strategic error prevention. In this paper, we describe a trend analysis method for human error events that have been accumulated in the organization and the utilization of the results of trend analysis to prevent accidents proactively. Although the systematic analysis of human error events, the monitoring of their overall trend, and the utilization of the analyzed results have been examined for the plant operation, such information has never been utilized completely. Sharing information on human error events and analyzing their causes lead to the clarification of problems in the management and human factors. This new method was applied to the human error events that occurred in the Rokkasho reprocessing plant from 2010 October. Results revealed that the output of this method is effective in judging the error prevention plan and that the number of human error events is reduced to about 50% those observed in 2009 and 2010. (author)

  20. The January 2001, El Salvador event: a multi-data analysis

    Science.gov (United States)

    Vallee, M.; Bouchon, M.; Schwartz, S. Y.

    2001-12-01

    On January 13, 2001, a large normal event (Mw=7.6) occured 100 kilometers away from the Salvadorian coast (Central America) with a centroid depth of about 50km. The size of this event is surprising according to the classical idea that such events have to be much weaker than thrust events in subduction zones. We analysed this earthquake with different types of data: because teleseismic waves are the only data which offer a good azimuthal coverage, we first built a kinematic source model with P and SH waves provided by the IRIS-GEOSCOPE networks. The ambiguity between the 30o plane (plunging toward Pacific Ocean) and the 60o degree plane (plunging toward Central America) leaded us to do a parallel analysis of the two possible planes. We used a simple point-source modelling in order to define the main characteristics of the event and then used an extended source to retrieve the kinematic features of the rupture. For the 2 possible planes, this analysis reveals a downdip and northwest rupture propagation but the difference of fit remains subtle even when using the extended source. In a second part we confronted our models for the two planes with other seismological data, which are (1) regional data, (2) surface wave data through an Empirical Green Function given by a similar but much weaker earthquake which occured in July 1996 and lastly (3) nearfield data provided by Universidad Centroamericana (UCA) and Centro de Investigationes Geotecnicas (CIG). Regional data do not allow to discriminate the 2 planes neither but surface waves and especially near field data confirm that the fault plane is the steepest one plunging toward Central America. Moreover, the slight directivity toward North is confirmed by surface waves.

  1. Many multicenter trials had few events per center, requiring analysis via random-effects models or GEEs.

    Science.gov (United States)

    Kahan, Brennan C; Harhay, Michael O

    2015-12-01

    Adjustment for center in multicenter trials is recommended when there are between-center differences or when randomization has been stratified by center. However, common methods of analysis (such as fixed-effects, Mantel-Haenszel, or stratified Cox models) often require a large number of patients or events per center to perform well. We reviewed 206 multicenter randomized trials published in four general medical journals to assess the average number of patients and events per center and determine whether appropriate methods of analysis were used in trials with few patients or events per center. The median number of events per center/treatment arm combination for trials using a binary or survival outcome was 3 (interquartile range, 1-10). Sixteen percent of trials had less than 1 event per center/treatment combination, 50% fewer than 3, and 63% fewer than 5. Of the trials which adjusted for center using a method of analysis which requires a large number of events per center, 6% had less than 1 event per center-treatment combination, 25% fewer than 3, and 50% fewer than 5. Methods of analysis that allow for few events per center, such as random-effects models or generalized estimating equations (GEEs), were rarely used. Many multicenter trials contain few events per center. Adjustment for center using random-effects models or GEE with model-based (non-robust) standard errors may be beneficial in these scenarios. Copyright © 2015 Elsevier Inc. All rights reserved.

  2. Detection of Abnormal Events via Optical Flow Feature Analysis

    Directory of Open Access Journals (Sweden)

    Tian Wang

    2015-03-01

    Full Text Available In this paper, a novel algorithm is proposed to detect abnormal events in video streams. The algorithm is based on the histogram of the optical flow orientation descriptor and the classification method. The details of the histogram of the optical flow orientation descriptor are illustrated for describing movement information of the global video frame or foreground frame. By combining one-class support vector machine and kernel principal component analysis methods, the abnormal events in the current frame can be detected after a learning period characterizing normal behaviors. The difference abnormal detection results are analyzed and explained. The proposed detection method is tested on benchmark datasets, then the experimental results show the effectiveness of the algorithm.

  3. Detection of Abnormal Events via Optical Flow Feature Analysis

    Science.gov (United States)

    Wang, Tian; Snoussi, Hichem

    2015-01-01

    In this paper, a novel algorithm is proposed to detect abnormal events in video streams. The algorithm is based on the histogram of the optical flow orientation descriptor and the classification method. The details of the histogram of the optical flow orientation descriptor are illustrated for describing movement information of the global video frame or foreground frame. By combining one-class support vector machine and kernel principal component analysis methods, the abnormal events in the current frame can be detected after a learning period characterizing normal behaviors. The difference abnormal detection results are analyzed and explained. The proposed detection method is tested on benchmark datasets, then the experimental results show the effectiveness of the algorithm. PMID:25811227

  4. Preterm Versus Term Children: Analysis of Sedation/Anesthesia Adverse Events and Longitudinal Risk.

    Science.gov (United States)

    Havidich, Jeana E; Beach, Michael; Dierdorf, Stephen F; Onega, Tracy; Suresh, Gautham; Cravero, Joseph P

    2016-03-01

    Preterm and former preterm children frequently require sedation/anesthesia for diagnostic and therapeutic procedures. Our objective was to determine the age at which children who are born risk for sedation/anesthesia adverse events. Our secondary objective was to describe the nature and incidence of adverse events. This is a prospective observational study of children receiving sedation/anesthesia for diagnostic and/or therapeutic procedures outside of the operating room by the Pediatric Sedation Research Consortium. A total of 57,227 patients 0 to 22 years of age were eligible for this study. All adverse events and descriptive terms were predefined. Logistic regression and locally weighted scatterplot regression were used for analysis. Preterm and former preterm children had higher adverse event rates (14.7% vs 8.5%) compared with children born at term. Our analysis revealed a biphasic pattern for the development of adverse sedation/anesthesia events. Airway and respiratory adverse events were most commonly reported. MRI scans were the most commonly performed procedures in both categories of patients. Patients born preterm are nearly twice as likely to develop sedation/anesthesia adverse events, and this risk continues up to 23 years of age. We recommend obtaining birth history during the formulation of an anesthetic/sedation plan, with heightened awareness that preterm and former preterm children may be at increased risk. Further prospective studies focusing on the etiology and prevention of adverse events in former preterm patients are warranted. Copyright © 2016 by the American Academy of Pediatrics.

  5. Assessment of Vulnerabilities of Operating Nuclear Power Plants to Extreme External Events

    International Nuclear Information System (INIS)

    2017-12-01

    The Fukushima Daiichi accident showed the need to explore scenarios where external hazards exceed the design basis. Knowledge of plant behaviour along those scenarios helps improve global safety, since the weak points can be identified and measures to limit the progression of potential accidents or to mitigate their consequences can be introduced. Based on an IAEA methodology document for Member States issued in 2011, the current publication expands the previous version by giving a more comprehensive approach and introducing the enhancements that could be identified from the research developments and practical applications in the recent years.

  6. Root cause analysis of relevant events

    International Nuclear Information System (INIS)

    Perez, Silvia S.; Vidal, Patricia G.

    2000-01-01

    During 1998 the research work followed more specific guidelines, which entailed focusing exclusively on the two selected methods (ASSET and HPIP) and incorporating some additional human behaviour elements based on the documents of reference. Once resident inspectors were incorporated in the project (and trained accordingly), events occurring in Argentine nuclear power plants were analysed. Some events were analysed (all of them from Atucha I and Embalse nuclear power plant), concluding that the systematic methodology used allows us to investigate also minor events that were precursors of the events selected. (author)

  7. EVNTRE, Code System for Event Progression Analysis for PRA

    International Nuclear Information System (INIS)

    2002-01-01

    1 - Description of program or function: EVNTRE is a generalized event tree processor that was developed for use in probabilistic risk analysis of severe accident progressions for nuclear power plants. The general nature of EVNTRE makes it applicable to a wide variety of analyses that involve the investigation of a progression of events which lead to a large number of sets of conditions or scenarios. EVNTRE efficiently processes large, complex event trees. It can assign probabilities to event tree branch points in several different ways, classify pathways or outcomes into user-specified groupings, and sample input distributions of probabilities and parameters. PSTEVNT, a post-processor program used to sort and reclassify the 'binned' data output from EVNTRE and generate summary tables, is included. 2 - Methods: EVNTRE processes event trees that are cast in the form of questions or events, with multiple choice answers for each question. Split fractions (probabilities or frequencies that sum to unity) are either supplied or calculated for the branches of each question in a path-dependent manner. EVNTRE traverses the tree, enumerating the leaves of the tree and calculating their probabilities or frequencies based upon the initial probability or frequency and the split fractions for the branches taken along the corresponding path to an individual leaf. The questions in the event tree are usually grouped to address specific phases of time regimes in the progression of the scenario or severe accident. Grouping or binning of each path through the event tree in terms of a small number of characteristics or attributes is allowed. Boolean expressions of the branches taken are used to select the appropriate values of the characteristics of interest for the given path. Typically, the user specifies a cutoff tolerance for the frequency of a pathway to terminate further exploration. Multiple sets of input to an event tree can be processed by using Monte Carlo sampling to generate

  8. Treatment of the loss of ultimate heat sink initiating events in the IRSN level 1 PSA

    International Nuclear Information System (INIS)

    Dupuy, Patricia; Georgescu, Gabriel; Corenwinder, Francois

    2014-01-01

    The total loss of the ultimate heat sink is an initiating event which, even it is mainly of external origin, has been considered in the frame of internal events Level 1 PSA by IRSN. The on-going actions on the development of external hazards PSA and the recent incident of loss of the heat sink induced by the ingress of vegetable matter that occurred in France in 2009 have pointed out the need to improve the modeling of the loss of the heat sink initiating event and sequences to better take into account the fact that this loss may be induced by external hazards and thus affect all the site units. The paper presents the historical steps of the modeling of the total loss of the heat sink, the safety stakes of this modeling, the main assumptions used by IRSN in the associated PSA for the 900 MWe reactors and the results obtained. The total loss of the heat sink was not initially addressed in the safety demonstration of French NPPs. On the basis of the insights of the first probabilistic assessments performed in the 80's, the risks associated to this 'multiple failure situation' turned out to be very significant and design and organisational improvements were implemented on the plants. Reviews of the characterization of external hazards and of their consequences on the installations and French operating feedback have revealed that extreme hazards may induce a total loss of the heat sink. Moreover, the accident that occurred at Fukushima in 2011 has pointed out the risk of such a loss of long duration at all site units in case of extreme hazards. In this context, it seems relevant to further improve the modelling of the total loss of the heat sink by considering the external hazards that may cause this loss. In a first step, IRSN has improved the assumptions and data used in the loss of the heat sink PSA model, in particular by considering that such a loss may affect all the site units. The next challenge will be the deeper analysis of the impact of external hazards on

  9. Impacts Of External Price Shocks On Malaysian Macro Economy-An Applied General Equilibrium Analysis

    Directory of Open Access Journals (Sweden)

    Abul Quasem Al-Amin

    2008-10-01

    Full Text Available This paper examines the impacts of external price shocks in the Malaysian economy. There are three simulations are carried out with different degrees of external shocks using Malaysian Social Accounting Matrix (SAM and Computable General Equilibrium (CGE analysis. The model results indicate that the import price shocks, better known as external price shocks by 15% decreases the domestic production of building and construction sector by 25.87%, hotels, restaurants and entertainment sector by 12.04%, industry sector by 12.02%, agriculture sector by 11.01%, and electricity and gas sector by 9.55% from the baseline. On the import side, our simulation results illustrate that as a result of the import price shocks by 15%, imports decreases significantly in all sectors from base level. Among the scenarios, the largest negative impacts goes on industry sectors by 29.67% followed by building and construction sector by 22.42%, hotels, restaurants and entertainment sector by 19.45%, electricity and gas sector by 13.%, agriculture sector by 12.63% and other service sectors by 11.17%. However significant negative impact goes to the investment and fixed capital investment. It also causes the household income, household consumption and household savings down and increases the cost of livings in the economy results in downward social welfare.

  10. Discrete event simulation tool for analysis of qualitative models of continuous processing systems

    Science.gov (United States)

    Malin, Jane T. (Inventor); Basham, Bryan D. (Inventor); Harris, Richard A. (Inventor)

    1990-01-01

    An artificial intelligence design and qualitative modeling tool is disclosed for creating computer models and simulating continuous activities, functions, and/or behavior using developed discrete event techniques. Conveniently, the tool is organized in four modules: library design module, model construction module, simulation module, and experimentation and analysis. The library design module supports the building of library knowledge including component classes and elements pertinent to a particular domain of continuous activities, functions, and behavior being modeled. The continuous behavior is defined discretely with respect to invocation statements, effect statements, and time delays. The functionality of the components is defined in terms of variable cluster instances, independent processes, and modes, further defined in terms of mode transition processes and mode dependent processes. Model construction utilizes the hierarchy of libraries and connects them with appropriate relations. The simulation executes a specialized initialization routine and executes events in a manner that includes selective inherency of characteristics through a time and event schema until the event queue in the simulator is emptied. The experimentation and analysis module supports analysis through the generation of appropriate log files and graphics developments and includes the ability of log file comparisons.

  11. External costs of energy - do the answers match the questions? Looking back at 10 years of ExternE

    International Nuclear Information System (INIS)

    Krewitt, W.

    2002-01-01

    While the claim for 'getting prices right' is quite popular in conceptual policy papers, the implementation of appropriate internalisation strategies is still hampered by a lack of reliable external cost data. Great expectations were set into the ExternE project, a major research programme launched by the European Commission at the beginning of the 1990s to provide a scientific basis for the quantification of energy related externalities and to give guidance supporting the design of internalisation measures. After more than a decade of research, the ExternE label became a well recognised standard source for external cost data. Looking back into the ExternE history, the paper pursues how emerging new scientific insights and changing background assumptions affected external cost estimates and related recommendations to policy over time. Based on ExternE results, the usefulness and inherent limitations of external cost estimates for impact categories like climate change or nuclear waste disposal is discussed. The paper also gives examples on how external costs in spite of remaining uncertainties are successfully used to support environmental policy. (Author)

  12. External Tank Liquid Hydrogen (LH2) Prepress Regression Analysis Independent Review Technical Consultation Report

    Science.gov (United States)

    Parsons, Vickie s.

    2009-01-01

    The request to conduct an independent review of regression models, developed for determining the expected Launch Commit Criteria (LCC) External Tank (ET)-04 cycle count for the Space Shuttle ET tanking process, was submitted to the NASA Engineering and Safety Center NESC on September 20, 2005. The NESC team performed an independent review of regression models documented in Prepress Regression Analysis, Tom Clark and Angela Krenn, 10/27/05. This consultation consisted of a peer review by statistical experts of the proposed regression models provided in the Prepress Regression Analysis. This document is the consultation's final report.

  13. Event dependent sampling of recurrent events

    DEFF Research Database (Denmark)

    Kvist, Tine Kajsa; Andersen, Per Kragh; Angst, Jules

    2010-01-01

    The effect of event-dependent sampling of processes consisting of recurrent events is investigated when analyzing whether the risk of recurrence increases with event count. We study the situation where processes are selected for study if an event occurs in a certain selection interval. Motivation...... retrospective and prospective disease course histories are used. We examine two methods to correct for the selection depending on which data are used in the analysis. In the first case, the conditional distribution of the process given the pre-selection history is determined. In the second case, an inverse...

  14. Single Event Upset Energy Dependence In a Buck-Converter Power Supply Design

    CERN Document Server

    Drake, G; The ATLAS collaboration; De Lurgio, P; Stanek, R; Mellado, B; Gopalakrishnan, A; Mahadik, S; Reed, R; Senthilkumaran, A

    2012-01-01

    We present a study of Single Event Upsets performed on a commercial pulse-width modulator controller chip that we are using for a switching power supply design for the Atlas Tile Calorimeter at the LHC. We performed tests to study the probability of an SEU occurring as a function of incident particle (hadron) energy. We compare the results with prediction from theory. We discuss the performance of the circuit, and perform an analysis using Bendel parameters. We also present a solution that we found using external circuitry that eliminates the effect.

  15. Closing session

    International Nuclear Information System (INIS)

    2014-01-01

    This part makes a summary of the different sessions and discussions of the workshop in a series of slide presentations: Summary of Opening Session; Summary of Session 1: Analysis of External Hazard Potential; Summary of session 2: Specific features of analysis and modeling of particular natural external hazards; Summary of session-3: Practices and research efforts on natural external events PSA; Summary of session 4: Modeling of NPP response to natural external events in PSA; Summary of session 5: Seismic Risk Analysis; Summary of session 6: Use of external events PSA with the focus on regulatory body role; Facilitated discussion 1 summary: Where do we stand in the analysis of external events?; Summary Facilitated Discussion 2: Findings and Good Practices for External Events Analysis

  16. Probabilistic safety analysis for fire events for the NPP Isar 2

    International Nuclear Information System (INIS)

    Schmaltz, H.; Hristodulidis, A.

    2007-01-01

    The 'Probabilistic Safety Analysis for Fire Events' (Fire-PSA KKI2) for the NPP Isar 2 was performed in addition to the PSA for full power operation and considers all possible events which can be initiated due to a fire. The aim of the plant specific Fire-PSA was to perform a quantitative assessment of fire events during full power operation, which is state of the art. Based on simplistic assumptions referring to the fire induced failures, the influence of system- and component-failures on the frequency of the core damage states was analysed. The Fire-PSA considers events, which will result due to fire-induced failures of equipment on the one hand in a SCRAM and on the other hand in events, which will not have direct operational effects but because of the fire-induced failure of safety related installations the plant will be shut down as a precautionary measure. These events are considered because they may have a not negligible influence on the frequency of core damage states in case of failures during the plant shut down because of the reduced redundancy of safety related systems. (orig.)

  17. The Externe project. Assessment of the external costs of the natural gas fuel cycle

    International Nuclear Information System (INIS)

    Holland, M.R.

    1997-01-01

    A detailed bottom-up methodology for assessment of the external costs of energy has been developed by a multi-disciplinary, pan-European team as part of the European Commissions's JOULE Programme. The consequences of the generation of electricity from fossil, nuclear and renewable technologies, in terms of damages to human health, buildings and the wider environment, have been assessed within a consistent framework. The potential application of the results in cost-benefit analysis, power system optimisation, emissions charging, etc. is also now under investigation. The analysis starts with definition of the fuel cycle, and specification of the technologies and locations to be considered. Results to date show that for typical modern examples of power plants burning different fossil fuels, externalities (including possible global warming effects) are lowest for gas-burning plant. (R.P.)

  18. Upgrading the electrical system of the IEA-R1 reactor to avoid triggering event of accidents

    International Nuclear Information System (INIS)

    Mello, Jose Roberto de; Madi Filho, Tufic

    2015-01-01

    The IEA-R1 research reactor at the Institute of Energy and Nuclear Research (IPEN) is a research reactor open pool type, built and designed by the American firm 'Babcox and Wilcox', having as coolant and moderator demineralized light water and Beryllium and graphite, as reflectors. The power supply system is designed to meet the electricity demand required by the loads of the reactor (Security systems and systems not related to security) in different situations the plant can meet, such as during startup, normal operation at power, shutdown, maintenance, exchange of fuel elements and accident situations. Studies have been done on possible accident initiating events and deterministic techniques were applied to assess the consequences of such incidents. Thus, the methods used to identify and select the accident initiating events, the methods of analysis of accidents, including sequence of events, transient analysis and radiological consequences, have been described. Finally, acceptance criteria of radiological doses are described. Only a brief summary of the item concerning loss of electrical power will be presented. The loss of normal electrical power at the IEA-R1 reactor is very common. In the case of Electric External Power Loss, at the IEA-R1 reactor building, there may be different sequences of events, as described below. When the supply of external energy in the IEA-R1 facility fails, the Electrical Distribution Vital System, consisting of 4 (four) generators type 'UPS', starts operation, immediately and it will continue supplying power to the reactor control table, core cooling system and other security systems. To contribute to security, in the electric power failure, starts to operate the Emergency Cooling System (SRE). SRE has the function of removing residual heat from the core to prevent the melting of fuel elements in the event of loss of refrigerant to the core. Adding to the generators with batteries group system, new auxiliary

  19. Analysis of manufacturing based on object oriented discrete event simulation

    Directory of Open Access Journals (Sweden)

    Eirik Borgen

    1990-01-01

    Full Text Available This paper describes SIMMEK, a computer-based tool for performing analysis of manufacturing systems, developed at the Production Engineering Laboratory, NTH-SINTEF. Its main use will be in analysis of job shop type of manufacturing. But certain facilities make it suitable for FMS as well as a production line manufacturing. This type of simulation is very useful in analysis of any types of changes that occur in a manufacturing system. These changes may be investments in new machines or equipment, a change in layout, a change in product mix, use of late shifts, etc. The effects these changes have on for instance the throughput, the amount of VIP, the costs or the net profit, can be analysed. And this can be done before the changes are made, and without disturbing the real system. Simulation takes into consideration, unlike other tools for analysis of manufacturing systems, uncertainty in arrival rates, process and operation times, and machine availability. It also shows the interaction effects a job which is late in one machine, has on the remaining machines in its route through the layout. It is these effects that cause every production plan not to be fulfilled completely. SIMMEK is based on discrete event simulation, and the modeling environment is object oriented. The object oriented models are transformed by an object linker into data structures executable by the simulation kernel. The processes of the entity objects, i.e. the products, are broken down to events and put into an event list. The user friendly graphical modeling environment makes it possible for end users to build models in a quick and reliable way, using terms from manufacturing. Various tests and a check of model logic are helpful functions when testing validity of the models. Integration with software packages, with business graphics and statistical functions, is convenient in the result presentation phase.

  20. Corrective action program at the Krsko NPP. Trending and analysis of minor events

    International Nuclear Information System (INIS)

    Bach, B.; Kavsek, D.

    2007-01-01

    Industry and On-site Operating Experience has shown that the significant events, minor events and near misses all share something in common: latent weaknesses that result in failed barriers and the same or similar (root) causes for that failure. All these types of events differ only in their resulting consequences: minor events and near misses have no immediate or significant impact to plant safety or reliability. However, the significant events are usually preceded by a number of those kinds of events and could be prevented from occurring if the root cause(s) of these precursor events could be identified and eliminated. It would be therefore poor management to leave minor events and near misses unreported and unanalysed. Reporting and analysing of minor events allows detection of latent weaknesses that may indicate the need for improvement. The benefit of low level event analysis is that deficiencies can be found in barriers that normally go unchallenged and may not be known that they are ineffective in stopping a significant event. In addition, large numbers of minor events and near misses may increase the probability of occurrence of a significant event, which in itself is a sufficient reason for addressing these types of events. However, as it is not often practical neither feasible to perform a detailed root cause determination for every minor events, trending and trend analysis are used to identify and correct the causes prior to their resulting in a significant event. Trending is monitoring a change in frequency of similar minor events occurrence. Adverse trend is an increase in the frequency of minor events which are sorted by commonality such as common equipment failure, human factors, common or similar causal factors, activity etc. or worsening performance of processes that has been trending. The primary goal of any trending programme should be to identify an adverse trend early enough that the operating organization can initiate an investigation to help

  1. Conjugate heat transfer analysis for in-vessel retention with external reactor vessel cooling

    International Nuclear Information System (INIS)

    Park, Jong-Woon; Bae, Jae-ho; Song, Hyuk-Jin

    2016-01-01

    Highlights: • A conjugate heat transfer analysis method is applied for in-vessel corium retention. • 3D heat diffusion has a formidable effect in alleviating focusing heat load from metallic layer. • The focusing heat load is decreased by about 2.5 times on the external surface. - Abstract: A conjugate heat transfer analysis method for the thermal integrity of a reactor vessel under external reactor vessel cooling conditions is developed to resolve light metal layer focusing effect issue for in-vessel retention. The method calculates steady-state three-dimensional temperature distribution of a reactor vessel using coupled conjugate heat transfer between in-vessel three-layered stratified corium (metallic pool, oxide pool and heavy metal and polar-angle dependent boiling heat transfer at the outer surface of a reactor vessel). The three-layer corium heat transfer model is utilizing lumped-parameter thermal-resistance circuit method. For the ex-vessel boiling boundary conditions, nucleate, transition and film boiling are considered. The thermal integrity of a reactor vessel is addressed in terms of heat flux at the outer-most nodes of the vessel and remaining thickness profile. The vessel three-dimensional heat conduction is validated against a commercial code. It is found that even though the internal heat flux from the metal layer goes far beyond critical heat flux (CHF) the heat flux from the outermost nodes of the vessel may be maintained below CHF due to massive vessel heat diffusion. The heat diffusion throughout the vessel is more pronounced for relatively low heat generation rate in an oxide pool. Parametric calculations are performed considering thermal conditions such as peak heat flux from a light metal layer, heat generation in an oxide pool and external boiling conditions. The major finding is that the most crucial factor for success of in-vessel retention is not the mass of the molten light metal above the oxide pool but the heat generation rate

  2. External cephalic version-related risks: a meta-analysis

    NARCIS (Netherlands)

    Grootscholten, K.; Kok, M.; Oei, S.G.; Mol, B.W.J.; Post, van der J.A.

    2008-01-01

    OBJECTIVE: To systematically review the literature on external cephalic version–related complications and to assess if the outcome of a version attempt is related to complications. DATA SOURCES: In March 2007 we searched MEDLINE, EMBASE, and the Cochrane Central Register of Controlled Trials.

  3. External Cephalic Version-Related Risks A Meta-analysis

    NARCIS (Netherlands)

    Grootscholten, Kim; Kok, Marjolein; Oei, S. Guid; Mol, Ben W. J.; van der Post, Joris A.

    2008-01-01

    OBJECTIVE: To systematically review the literature on external cephalic version-related complications and to assess if the outcome of a version attempt is related to complications. DATA SOURCES: In March 2007 we searched MEDLINE, EMBASE, and the Cochrane Central Register of Controlled Trials.

  4. Re-presentations of space in Hollywood movies: an event-indexing analysis.

    Science.gov (United States)

    Cutting, James; Iricinschi, Catalina

    2015-03-01

    Popular movies present chunk-like events (scenes and subscenes) that promote episodic, serial updating of viewers' representations of the ongoing narrative. Event-indexing theory would suggest that the beginnings of new scenes trigger these updates, which in turn require more cognitive processing. Typically, a new movie event is signaled by an establishing shot, one providing more background information and a longer look than the average shot. Our analysis of 24 films reconfirms this. More important, we show that, when returning to a previously shown location, the re-establishing shot reduces both context and duration while remaining greater than the average shot. In general, location shifts dominate character and time shifts in event segmentation of movies. In addition, over the last 70 years re-establishing shots have become more like the noninitial shots of a scene. Establishing shots have also approached noninitial shot scales, but not their durations. Such results suggest that film form is evolving, perhaps to suit more rapid encoding of narrative events. Copyright © 2014 Cognitive Science Society, Inc.

  5. A hydrological analysis of the 4 November 2011 event in Genoa

    Directory of Open Access Journals (Sweden)

    F. Silvestro

    2012-09-01

    Full Text Available On the 4 November 2011 a flash flood event hit the area of Genoa with dramatic consequences. Such an event represents, from the meteorological and hydrological perspective, a paradigm of flash floods in the Mediterranean environment.

    The hydro-meteorological probabilistic forecasting system for small and medium size catchments in use at the Civil Protection Centre of Liguria region exhibited excellent performances for the event, by predicting, 24–48 h in advance, the potential level of risk associated with the forecast. It greatly helped the decision makers in issuing a timely and correct alert.

    In this work we present the operational outputs of the system provided during the Liguria events and the post event hydrological modelling analysis that has been carried out accounting also for the crowd sourcing information and data. We discuss the benefit of the implemented probabilistic systems for decision-making under uncertainty, highlighting how, in this case, the multi-catchment approach used for predicting floods in small basins has been crucial.

  6. Data driven analysis of rain events: feature extraction, clustering, microphysical /macro physical relationship

    Science.gov (United States)

    Djallel Dilmi, Mohamed; Mallet, Cécile; Barthes, Laurent; Chazottes, Aymeric

    2017-04-01

    The study of rain time series records is mainly carried out using rainfall rate or rain accumulation parameters estimated on a fixed integration time (typically 1 min, 1 hour or 1 day). In this study we used the concept of rain event. In fact, the discrete and intermittent natures of rain processes make the definition of some features inadequate when defined on a fixed duration. Long integration times (hour, day) lead to mix rainy and clear air periods in the same sample. Small integration time (seconds, minutes) will lead to noisy data with a great sensibility to detector characteristics. The analysis on the whole rain event instead of individual short duration samples of a fixed duration allows to clarify relationships between features, in particular between macro physical and microphysical ones. This approach allows suppressing the intra-event variability partly due to measurement uncertainties and allows focusing on physical processes. An algorithm based on Genetic Algorithm (GA) and Self Organising Maps (SOM) is developed to obtain a parsimonious characterisation of rain events using a minimal set of variables. The use of self-organizing map (SOM) is justified by the fact that it allows to map a high dimensional data space in a two-dimensional space while preserving as much as possible the initial space topology in an unsupervised way. The obtained SOM allows providing the dependencies between variables and consequently removing redundant variables leading to a minimal subset of only five features (the event duration, the rain rate peak, the rain event depth, the event rain rate standard deviation and the absolute rain rate variation of order 0.5). To confirm relevance of the five selected features the corresponding SOM is analyzed. This analysis shows clearly the existence of relationships between features. It also shows the independence of the inter-event time (IETp) feature or the weak dependence of the Dry percentage in event (Dd%e) feature. This confirms

  7. Analysis of events related to cracks and leaks in the reactor coolant pressure boundary

    Energy Technology Data Exchange (ETDEWEB)

    Ballesteros, Antonio, E-mail: Antonio.Ballesteros-Avila@ec.europa.eu [JRC-IET: Institute for Energy and Transport of the Joint Research Centre of the European Commission, Postbus 2, NL-1755 ZG Petten (Netherlands); Sanda, Radian; Peinador, Miguel; Zerger, Benoit [JRC-IET: Institute for Energy and Transport of the Joint Research Centre of the European Commission, Postbus 2, NL-1755 ZG Petten (Netherlands); Negri, Patrice [IRSN: Institut de Radioprotection et de Sûreté Nucléaire (France); Wenke, Rainer [GRS: Gesellschaft für Anlagen- und Reaktorsicherheit (GRS) mbH (Germany)

    2014-08-15

    Highlights: • The important role of Operating Experience Feedback is emphasised. • Events relating to cracks and leaks in the reactor coolant pressure boundary are analysed. • A methodology for event investigation is described. • Some illustrative results of the analysis of events for specific components are presented. - Abstract: The presence of cracks and leaks in the reactor coolant pressure boundary may jeopardise the safe operation of nuclear power plants. Analysis of cracks and leaks related events is an important task for the prevention of their recurrence, which should be performed in the context of activities on Operating Experience Feedback. In response to this concern, the EU Clearinghouse operated by the JRC-IET supports and develops technical and scientific work to disseminate the lessons learned from past operating experience. In particular, concerning cracks and leaks, the studies carried out in collaboration with IRSN and GRS have allowed to identify the most sensitive areas to degradation in the plant primary system and to elaborate recommendations for upgrading the maintenance, ageing management and inspection programmes. An overview of the methodology used in the analysis of cracks and leaks related events is presented in this paper, together with the relevant results obtained in the study.

  8. Frequency and time domain analysis of an external cavity laser with strong filtered optical feedback

    DEFF Research Database (Denmark)

    Detoma, Enrico; Tromborg, Bjarne; Montrosset, Ivo

    The stability properties of an external cavity laser with strong grating-filtered optical feedback to an anti-reflection coated facet are studied with a general frequency domain model. The model takes into account non-linear effects like four wave mixing and gain compression. A small......-signal analysis in the frequency domain allows a calculation of the range of operation without mode hopping around the grating reflectivity peak. This region should be as large as possible for proper operation of the tunable laser source. The analysis shows this stabilizing effect of mode coupling and gain...

  9. Integration of risk matrix and event tree analysis: a natural stone ...

    Indian Academy of Sciences (India)

    M Kemal Özfirat

    2017-09-27

    Sep 27, 2017 ... Different types of accidents may occur in natural stone facilities during movement, dimensioning, cutting ... are numerous risk analysis methods such as preliminary ..... machine type and maintenance (MM) event, block control.

  10. Making sense of root cause analysis investigations of surgery-related adverse events.

    Science.gov (United States)

    Cassin, Bryce R; Barach, Paul R

    2012-02-01

    This article discusses the limitations of root cause analysis (RCA) for surgical adverse events. Making sense of adverse events involves an appreciation of the unique features in a problematic situation, which resist generalization to other contexts. The top priority of adverse event investigations must be to inform the design of systems that help clinicians to adapt and respond effectively in real time to undesirable combinations of design, performance, and circumstance. RCAs can create opportunities in the clinical workplace for clinicians to reflect on local barriers and identify enablers of safe and reliable outcomes. Copyright © 2012 Elsevier Inc. All rights reserved.

  11. Disruptive Event Biosphere Dose Conversion Factor Analysis

    Energy Technology Data Exchange (ETDEWEB)

    M. Wasiolek

    2004-09-08

    This analysis report is one of the technical reports containing documentation of the Environmental Radiation Model for Yucca Mountain, Nevada (ERMYN), a biosphere model supporting the total system performance assessment (TSPA) for the license application (LA) for the Yucca Mountain repository. This analysis report describes the development of biosphere dose conversion factors (BDCFs) for the volcanic ash exposure scenario, and the development of dose factors for calculating inhalation dose during volcanic eruption. A graphical representation of the documentation hierarchy for the ERMYN is presented in Figure 1-1. This figure shows the interrelationships among the products (i.e., analysis and model reports) developed for biosphere modeling and provides an understanding of how this analysis report contributes to biosphere modeling. This report is one of two reports that develop biosphere BDCFs, which are input parameters for the TSPA model. The ''Biosphere Model Report'' (BSC 2004 [DIRS 169460]) describes in detail the ERMYN conceptual model and mathematical model. The input parameter reports, shown to the right of the Biosphere Model Report in Figure 1-1, contain detailed descriptions of the model input parameters, their development and the relationship between the parameters and specific features, events and processes (FEPs). This report describes biosphere model calculations and their output, the BDCFs, for the volcanic ash exposure scenario. This analysis receives direct input from the outputs of the ''Biosphere Model Report'' (BSC 2004 [DIRS 169460]) and from the five analyses that develop parameter values for the biosphere model (BSC 2004 [DIRS 169671]; BSC 2004 [DIRS 169672]; BSC 2004 [DIRS 169673]; BSC 2004 [DIRS 169458]; and BSC 2004 [DIRS 169459]). The results of this report are further analyzed in the ''Biosphere Dose Conversion Factor Importance and Sensitivity Analysis''. The objective of this

  12. Disruptive Event Biosphere Dose Conversion Factor Analysis

    International Nuclear Information System (INIS)

    M. Wasiolek

    2004-01-01

    This analysis report is one of the technical reports containing documentation of the Environmental Radiation Model for Yucca Mountain, Nevada (ERMYN), a biosphere model supporting the total system performance assessment (TSPA) for the license application (LA) for the Yucca Mountain repository. This analysis report describes the development of biosphere dose conversion factors (BDCFs) for the volcanic ash exposure scenario, and the development of dose factors for calculating inhalation dose during volcanic eruption. A graphical representation of the documentation hierarchy for the ERMYN is presented in Figure 1-1. This figure shows the interrelationships among the products (i.e., analysis and model reports) developed for biosphere modeling and provides an understanding of how this analysis report contributes to biosphere modeling. This report is one of two reports that develop biosphere BDCFs, which are input parameters for the TSPA model. The ''Biosphere Model Report'' (BSC 2004 [DIRS 169460]) describes in detail the ERMYN conceptual model and mathematical model. The input parameter reports, shown to the right of the Biosphere Model Report in Figure 1-1, contain detailed descriptions of the model input parameters, their development and the relationship between the parameters and specific features, events and processes (FEPs). This report describes biosphere model calculations and their output, the BDCFs, for the volcanic ash exposure scenario. This analysis receives direct input from the outputs of the ''Biosphere Model Report'' (BSC 2004 [DIRS 169460]) and from the five analyses that develop parameter values for the biosphere model (BSC 2004 [DIRS 169671]; BSC 2004 [DIRS 169672]; BSC 2004 [DIRS 169673]; BSC 2004 [DIRS 169458]; and BSC 2004 [DIRS 169459]). The results of this report are further analyzed in the ''Biosphere Dose Conversion Factor Importance and Sensitivity Analysis''. The objective of this analysis was to develop the BDCFs for the volcanic ash

  13. Event-by-event jet quenching

    Energy Technology Data Exchange (ETDEWEB)

    Fries, R.J.; Rodriguez, R.; Ramirez, E.

    2010-08-14

    High momentum jets and hadrons can be used as probes for the quark gluon plasma (QGP) formed in nuclear collisions at high energies. We investigate the influence of fluctuations in the fireball on jet quenching observables by comparing propagation of light quarks and gluons through averaged, smooth QGP fireballs with event-by-event jet quenching using realistic inhomogeneous fireballs. We find that the transverse momentum and impact parameter dependence of the nuclear modification factor R{sub AA} can be fit well in an event-by-event quenching scenario within experimental errors. However the transport coefficient {cflx q} extracted from fits to the measured nuclear modification factor R{sub AA} in averaged fireballs underestimates the value from event-by-event calculations by up to 50%. On the other hand, after adjusting {cflx q} to fit R{sub AA} in the event-by-event analysis we find residual deviations in the azimuthal asymmetry v{sub 2} and in two-particle correlations, that provide a possible faint signature for a spatial tomography of the fireball. We discuss a correlation function that is a measure for spatial inhomogeneities in a collision and can be constrained from data.

  14. Event-by-event jet quenching

    Energy Technology Data Exchange (ETDEWEB)

    Rodriguez, R. [Cyclotron Institute and Physics Department, Texas A and M University, College Station, TX 77843 (United States); Fries, R.J., E-mail: rjfries@comp.tamu.ed [Cyclotron Institute and Physics Department, Texas A and M University, College Station, TX 77843 (United States); RIKEN/BNL Research Center, Brookhaven National Laboratory, Upton, NY 11973 (United States); Ramirez, E. [Physics Department, University of Texas El Paso, El Paso, TX 79968 (United States)

    2010-09-27

    High momentum jets and hadrons can be used as probes for the quark gluon plasma (QGP) formed in nuclear collisions at high energies. We investigate the influence of fluctuations in the fireball on jet quenching observables by comparing propagation of light quarks and gluons through averaged, smooth QGP fireballs with event-by-event jet quenching using realistic inhomogeneous fireballs. We find that the transverse momentum and impact parameter dependence of the nuclear modification factor R{sub AA} can be fit well in an event-by-event quenching scenario within experimental errors. However the transport coefficient q extracted from fits to the measured nuclear modification factor R{sub AA} in averaged fireballs underestimates the value from event-by-event calculations by up to 50%. On the other hand, after adjusting q to fit R{sub AA} in the event-by-event analysis we find residual deviations in the azimuthal asymmetry v{sub 2} and in two-particle correlations, that provide a possible faint signature for a spatial tomography of the fireball. We discuss a correlation function that is a measure for spatial inhomogeneities in a collision and can be constrained from data.

  15. 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)

  16. Root-Cause Analysis of a Potentially Sentinel Transfusion Event: Lessons for Improvement of Patient Safety

    Directory of Open Access Journals (Sweden)

    Ali Reza Jeddian

    2012-09-01

    Full Text Available Errors prevention and patient safety in transfusion medicine are a serious concern. Errors can occur at any step in transfusion and evaluation of their root causes can be helpful for preventive measures. Root cause analysis as a structured and systematic approach can be used for identification of underlying causes of adverse events. To specify system vulnerabilities and illustrate the potential of such an approach, we describe the root cause analysis of a case of transfusion error in emergency ward that could have been fatal. After reporting of the mentioned event, through reviewing records and interviews with the responsible personnel, the details of the incident were elaborated. Then, an expert panel meeting was held to define event timeline and the care and service delivery problems and discuss their underlying causes, safeguards and preventive measures. Root cause analysis of the mentioned event demonstrated that certain defects of the system and the ensuing errors were main causes of the event. It also points out systematic corrective actions. It can be concluded that health care organizations should endeavor to provide opportunities to discuss errors and adverse events and introduce preventive measures to find areas where resources need to be allocated to improve patient safety.

  17. Internalisation of external cost in the power generation sector: Analysis with Global Multi-regional MARKAL model

    International Nuclear Information System (INIS)

    Rafaj, Peter; Kypreos, Socrates

    2007-01-01

    The Global MARKAL-Model (GMM), a multi-regional 'bottom-up' partial equilibrium model of the global energy system with endogenous technological learning, is used to address impacts of internalisation of external costs from power production. This modelling approach imposes additional charges on electricity generation, which reflect the costs of environmental and health damages from local pollutants (SO 2 , NO x ) and climate change, wastes, occupational health, risk of accidents, noise and other burdens. Technologies allowing abatement of pollutants emitted from power plants are rapidly introduced into the energy system, for example, desulphurisation, NO x removal, and CO 2 scrubbers. The modelling results indicate substantial changes in the electricity production system in favour of natural gas combined cycle, nuclear power and renewables induced by internalisation of external costs and also efficiency loss due to the use of scrubbers. Structural changes and fuel switching in the electricity sector result in significant reduction of emissions of both local pollution and CO 2 over the modelled time period. Strong decarbonisation impact of internalising local externalities suggests that ancillary benefits can be expected from policies directly addressing other issues then CO 2 mitigation. Finally, the detailed analysis of the total generation cost of different technologies points out that inclusion of external cost in the price of electricity increases competitiveness of non-fossil generation sources and fossil power plants with emission control

  18. An indicator for ecosystem externalities in fishing

    DEFF Research Database (Denmark)

    Ravn-Jonsen, Lars; Andersen, Ken Haste; Vestergaard, Niels

    2016-01-01

    Ecosystem externalities arise when one use of an ecosystem affects its other uses through the production functions of the ecosystem. We use simulations with a size-spectrum ecosystem model to investigate the ecosystem externality created by fishing of multiple species. The model is based upon...... general ecological principles and is calibrated to the North Sea. Two fleets are considered: a "forage fish" fleet targeting species that mature at small sizes and a "large fish" fleet targeting large piscivorous species. Based on the marginal analysis of the present value of the rent, we develop...... a benefit indicator that explicitly divides the consequences of fishing into internal and external benefits. This analysis demonstrates that the forage fish fleet has a notable economic impact on the large fish fleet, but the reverse is not true. The impact can be either negative or positive, which entails...

  19. Analysis of unintended events in hospitals: inter-rater reliability of constructing causal trees and classifying root causes

    NARCIS (Netherlands)

    Smits, M.; Janssen, J.; Vet, de H.C.W.; Zwaan, L.; Timmermans, D.R.M.; Groenewegen, P.P.; Wagner, C.

    2009-01-01

    BACKGROUND: Root cause analysis is a method to examine causes of unintended events. PRISMA (Prevention and Recovery Information System for Monitoring and Analysis: is a root cause analysis tool. With PRISMA, events are described in causal trees and root causes are subsequently classified with the

  20. Analysis of unintended events in hospitals : inter-rater reliability of constructing causal trees and classifying root causes

    NARCIS (Netherlands)

    Smits, M.; Janssen, J.; Vet, R. de; Zwaan, L.; Groenewegen, P.P.; Timmermans, D.

    2009-01-01

    Background. Root cause analysis is a method to examine causes of unintended events. PRISMA (Prevention and Recovery Information System for Monitoring and Analysis) is a root cause analysis tool. With PRISMA, events are described in causal trees and root causes are subsequently classified with the

  1. Analysis of unintended events in hospitals: inter-rater reliability of constructing causal trees and classifying root causes.

    NARCIS (Netherlands)

    Smits, M.; Janssen, J.; Vet, R. de; Zwaan, L.; Timmermans, D.; Groenewegen, P.; Wagner, C.

    2009-01-01

    Background: Root cause analysis is a method to examine causes of unintended events. PRISMA (Prevention and Recovery Information System for Monitoring and Analysis) is a root cause analysis tool. With PRISMA, events are described in causal trees and root causes are subsequently classified with the

  2. External costs of nuclear-generated electricity

    International Nuclear Information System (INIS)

    Rotaru, I.; Glodeanu, F.; Popescu, D.; Andrei, V.

    2004-01-01

    External costs of nuclear power include: future financial liabilities arising from decommissioning and dismantling of nuclear facilities, health and environmental impacts of radioactivity releases in routine operation, radioactive waste disposal and effects of severe accidents. The nuclear energy industry operates under regulations that impose stringent limits to atmospheric emissions and liquid effluents from nuclear facilities as well as requiring the containment and confinement of solid radioactive waste to ensure its isolation from the biosphere as long as it may be harmful for human health and the environment. The capital and operating costs of nuclear power plants and fuel cycle facilities already internalize a major portion of the above-mentioned potential external costs, and these are reflected in the prices paid by consumers of nuclear-generated electricity. The externality related to potential health and environmental impacts of radioactive releases during routine operations have been assessed in a large number of comprehensive studies, in particular the ExternE project that was created in the framework of the European Commission. With regard to effects of severe nuclear accidents, a special legal regime, the third-party liability system, has been implemented to provide limited third party liability coverage in the event of a nuclear accident. The nuclear plant owners are held liable for some specified first substantial part of damages to third parties, and must secure insurance coverage adequate to cover this part. The Government provides coverage for some specified substantial second part of the damages, with any remaining damages to be considered by the national legislation. Thus, the costs of an incident or accident are fully internalized in the costs borne by the nuclear plant owners. Externalities of energy are not limited to environmental and health related impacts, but may result also from macro-economic, policy or strategic factors not reflected

  3. Economic Multipliers and Mega-Event Analysis

    OpenAIRE

    Victor Matheson

    2004-01-01

    Critics of economic impact studies that purport to show that mega-events such as the Olympics bring large benefits to the communities “lucky” enough to host them frequently cite the use of inappropriate multipliers as a primary reason why these impact studies overstate the true economic gains to the hosts of these events. This brief paper shows in a numerical example how mega-events may lead to inflated multipliers and exaggerated claims of economic benefits.

  4. External costs related to power production technologies. ExternE national implementation for Denmark

    International Nuclear Information System (INIS)

    Schleisner, L.; Sieverts Nielsen, P.

    1997-12-01

    The objective of the ExternE National Implementation project has been to establish a comprehensive and comparable set of data on externalities of power generation for all EU member states and Norway. The tasks include the application of the ExternE methodology to the most important fuel cycles for each country as well as to update the already existing results; to aggregate these site- and technology-specific results to more general figures. The current report covers the results of the national implementation for Denmark. Three different fuel cycles have been chosen as case studies. These are fuel cycles for an offshore wind farm and a wind farm on land, a decentralised CHP plant based on natural gas and a decentralised CHP plant based on biogas. The report covers all the details of the application of the methodology to these fuel cycles aggregation to a national level. (au) EU-JOULE 3. 59 tabs., 25 ills., 61 refs

  5. External costs related to power production technologies. ExternE national implementation for Denmark

    Energy Technology Data Exchange (ETDEWEB)

    Schleisner, L; Sieverts Nielsen, P

    1997-12-01

    The objective of the ExternE National Implementation project has been to establish a comprehensive and comparable set of data on externalities of power generation for all EU member states and Norway. The tasks include the application of the ExternE methodology to the most important fuel cycles for each country as well as to update the already existing results; to aggregate these site- and technology-specific results to more general figures. The current report covers the results of the national implementation for Denmark. Three different fuel cycles have been chosen as case studies. These are fuel cycles for an offshore wind farm and a wind farm on land, a decentralised CHP plant based on natural gas and a decentralised CHP plant based on biogas. The report covers all the details of the application of the methodology to these fuel cycles aggregation to a national level. (au) EU-JOULE 3. 59 tabs., 25 ills., 61 refs.

  6. Environmental externalities related to power production on biogas and natural gas based on the EU ExternE methodology

    DEFF Research Database (Denmark)

    Nielsen, Per Sieverts; Ibsen, Liselotte Schleisner

    1998-01-01

    This paper assesses the environmental impacts and external costs from selected electricity generation systems in Denmark. The assessment is carried out as part of the ExternE National Implementation, which is the second phase of the ExternE project and involves case studies from all Western...... European countries. The project use a “bottom-up” methodology to evaluate the external costs associated with a wide range of different fuel cycles. The project has identified priority impacts, where most are impacts from air emissions. Externalities due to atmospheric emissions are calculated through...

  7. The limiting events transient analysis by RETRAN02 and VIPRE01 for an ABWR

    International Nuclear Information System (INIS)

    Tsai Chiungwen; Shih Chunkuan; Wang Jongrong; Lin Haotzu; Jin Jiunan; Cheng Suchin

    2009-01-01

    This paper describes the transient analysis of generator load rejection (LR) and One Turbine Control Valve Closure (OTCVC) events for Lungmen nuclear power plant (LMNPP). According to the Critical Power Ratio (CPR) criterion, the Preliminary Safety Analysis Report (PSAR) concluded that LR and OTCVC are the first and second limiting events respectively. In addition, the fuel type is changed from GE12 to GE14 now. It's necessary to re-analyze these two events for safety consideration. In this study, to quantify the impact to reactor, the difference of initial critical power ratio (ICPR) and minimum critical power ratio (MCPR), ie. ΔCPR is calculated. The ΔCPRs of the LR and OTCVC events are calculated with the combination of RETRAN02 and VIPRE01 codes. In RETRAN02 calculation, a thermal-hydraulic model was prepared for the transient analysis. The data including upper plenum pressure, core inlet flow, normalized power, and axial power shapes during transient are furthermore submitted into VIPRE01 for ΔCPR calculation. In VIPRE01 calculation, there was a hot channel model built to simulate the hottest fuel bundle. Based on the thermal-hydraulic data from RETRAN02, the ΔCPRs are calculated by VIPRE01 hot channel model. Additionally, the different TCV control modes are considered to study the influence of different TCV closure curves on transient behavior. Meanwhile, sensitivity studies including different initial system pressure and different initial power/flow conditions are also considered. Based on this analysis, the maximum ΔCPRs for LR and OTCVC are 0.162 and 0.191 respectively. According CPR criterion, the result shows that the impact caused by OTCVC event leads to be larger than LR event. (author)

  8. The null-event method in computer simulation

    International Nuclear Information System (INIS)

    Lin, S.L.

    1978-01-01

    The simulation of collisions of ions moving under the influence of an external field through a neutral gas to non-zero temperatures is discussed as an example of computer models of processes in which a probe particle undergoes a series of interactions with an ensemble of other particles, such that the frequency and outcome of the events depends on internal properties of the second particles. The introduction of null events removes the need for much complicated algebra, leads to a more efficient simulation and reduces the likelihood of logical error. (Auth.)

  9. Axial displacement of external and internal implant-abutment connection evaluated by linear mixed model analysis.

    Science.gov (United States)

    Seol, Hyon-Woo; Heo, Seong-Joo; Koak, Jai-Young; Kim, Seong-Kyun; Kim, Shin-Koo

    2015-01-01

    To analyze the axial displacement of external and internal implant-abutment connection after cyclic loading. Three groups of external abutments (Ext group), an internal tapered one-piece-type abutment (Int-1 group), and an internal tapered two-piece-type abutment (Int-2 group) were prepared. Cyclic loading was applied to implant-abutment assemblies at 150 N with a frequency of 3 Hz. The amount of axial displacement, the Periotest values (PTVs), and the removal torque values(RTVs) were measured. Both a repeated measures analysis of variance and pattern analysis based on the linear mixed model were used for statistical analysis. Scanning electron microscopy (SEM) was used to evaluate the surface of the implant-abutment connection. The mean axial displacements after 1,000,000 cycles were 0.6 μm in the Ext group, 3.7 μm in the Int-1 group, and 9.0 μm in the Int-2 group. Pattern analysis revealed a breakpoint at 171 cycles. The Ext group showed no declining pattern, and the Int-1 group showed no declining pattern after the breakpoint (171 cycles). However, the Int-2 group experienced continuous axial displacement. After cyclic loading, the PTV decreased in the Int-2 group, and the RTV decreased in all groups. SEM imaging revealed surface wear in all groups. Axial displacement and surface wear occurred in all groups. The PTVs remained stable, but the RTVs decreased after cyclic loading. Based on linear mixed model analysis, the Ext and Int-1 groups' axial displacements plateaued after little cyclic loading. The Int-2 group's rate of axial displacement slowed after 100,000 cycles.

  10. Associations of Parenting Dimensions and Styles with Externalizing Problems of Children and Adolescents: An Updated Meta-Analysis

    Science.gov (United States)

    Pinquart, Martin

    2017-01-01

    The present meta-analysis integrates research from 1,435 studies on associations of parenting dimensions and styles with externalizing symptoms in children and adolescents. Parental warmth, behavioral control, autonomy granting, and an authoritative parenting style showed very small to small negative concurrent and longitudinal associations with…

  11. Soil-structural interaction analysis of RBMK type NPP for seismic event. Progress report. From 1 July 1998 - 30 June 1999

    International Nuclear Information System (INIS)

    1999-01-01

    The objective of the project is to assess the structural behavior and safety capacity of a RBMK-1000 MW Main Building Complex under critical combination of loads including seismic events. This project is part of the Coordinated Research Program carried out by International Atomic Energy Agency on safety of RBMK Type Nuclear Power Plants (NPP) in Relation to External Events. The nuclear power plant considered for this study is the Sosnovy Bor NPP, located near St.Petersburg, Russia. The Soviet standard design RBMK-1000 MW type units installed in Sosnovy Bor NPP were originally designed for a Safe Shutdown Earthquake (SSE) with a peak ground acceleration (PGA) of 0.1 g. The relevant response spectra are not available for reference and assessment. The new international requirements for nuclear power plants in operation require site specific seismic hazard studies as a basis for the definition of a Review Level Earthquake (RLE) for reassessment of the structures and safety related equipment Ell - As the RLE site specific seismic data is still not available, the RLE earthquake spectra for Kozloduy NPP scaled to PGA=0.1 g were used in this study. This value is intentionally chosen for comparison purposes. The Russian design requirements (if design floor response spectra are available) will be compared with the international regulations. The scope of the study is to perform a Soil-Structure Interaction (SSI) seismic response analysis of the referenced RBMK-11000 MW. Main Building Complex to evaluate the effect on the structural response of a greater than design earthquake. The analysis is focused on a realistic assessment of the structural response to a potentially higher earthquake level instead of a conservative design type analysis. Special attention is paid on the seismic response of the sub-structures in the safe shutdown path, as well as on the locations of the heavy equipment

  12. Externalization versus Internalization of Sound in Normal-hearing and Hearing-impaired Listeners

    DEFF Research Database (Denmark)

    Ohl, Björn; Laugesen, Søren; Buchholz, Jörg

    2010-01-01

    The externalization of sound, i. e. the perception of auditory events as being located outside of the head, is a natural phenomenon for normalhearing listeners, when perceiving sound coming from a distant physical sound source. It is potentially useful for hearing in background noise......, but the relevant cues might be distorted by a hearing impairment and also by the processing of the incoming sound through hearing aids. In this project, two intuitive tests in natural real-life surroundings were developed, which capture the limits of the perception of externalization. For this purpose...

  13. DISRUPTIVE EVENT BIOSPHERE DOSE CONVERSION FACTOR ANALYSIS

    International Nuclear Information System (INIS)

    M.A. Wasiolek

    2005-01-01

    This analysis report is one of the technical reports containing documentation of the Environmental Radiation Model for Yucca Mountain, Nevada (ERMYN), a biosphere model supporting the total system performance assessment (TSPA) for the license application (LA) for the Yucca Mountain repository. This analysis report describes the development of biosphere dose conversion factors (BDCFs) for the volcanic ash exposure scenario, and the development of dose factors for calculating inhalation dose during volcanic eruption. A graphical representation of the documentation hierarchy for the ERMYN is presented in Figure 1-1. This figure shows the interrelationships among the products (i.e., analysis and model reports) developed for biosphere modeling and provides an understanding of how this analysis report contributes to biosphere modeling. This report is one of two reports that develop biosphere BDCFs, which are input parameters for the TSPA model. The Biosphere Model Report (BSC 2004 [DIRS 169460]) describes in detail the ERMYN conceptual model and mathematical model. The input parameter reports, shown to the right of the Biosphere Model Report in Figure 1-1, contain detailed descriptions of the model input parameters, their development and the relationship between the parameters and specific features, events and processes (FEPs). This report describes biosphere model calculations and their output, the BDCFs, for the volcanic ash exposure scenario. This analysis receives direct input from the outputs of the ''Biosphere Model Report'' (BSC 2004 [DIRS 169460]) and from the five analyses that develop parameter values for the biosphere model (BSC 2005 [DIRS 172827]; BSC 2004 [DIRS 169672]; BSC 2004 [DIRS 169673]; BSC 2004 [DIRS 169458]; and BSC 2004 [DIRS 169459]). The results of this report are further analyzed in the ''Biosphere Dose Conversion Factor Importance and Sensitivity Analysis'' (Figure 1-1). The objective of this analysis was to develop the BDCFs for the volcanic

  14. Mountain Rivers and Climate Change: Analysis of hazardous events in torrents of small alpine watersheds

    Science.gov (United States)

    Lutzmann, Silke; Sass, Oliver

    2016-04-01

    Torrential processes like flooding, heavy bedload transport or debris flows in steep mountain channels emerge during intense, highly localized rainfall events. They pose a serious risk on the densely populated Alpine region. Hydrogeomorphic hazards are profoundly nonlinear, threshold mediated phenomena frequently causing costly damage to infrastructure and people. Thus, in the context of climate change, there is an ever rising interest in whether sediment cascades of small alpine catchments react to changing precipitation patterns and how the climate signal is propagated through the fluvial system. We intend to answer the following research questions: (i) What are critical meteorological characteristics triggering torrential events in the Eastern Alps of Austria? (ii) The effect of external triggers is strongly mediated by the internal disposition of catchments to respond. Which factors control the internal susceptibility? (iii) Do torrential processes show an increase in magnitude and frequency or a shift in seasonality in the recent past? (iv) Which future changes can be expected under different climate scenarios? Quantifications of bedload transport in small alpine catchments are rare and often associated with high uncertainties. Detailed knowledge though exists for the Schöttlbach catchment, a 71 km2 study area in Styria in the Eastern Alps. The torrent is monitored since a heavy precipitation event resulted in a disastrous flood in July 2011. Sediment mobilisation from slopes as well as within-channel storage and fluxes are regularly measured by photogrammetric methods and sediment impact sensors (SIS). The associated hydro-meteorological conditions are known from a dense station network. Changing states of connectivity can thus be related to precipitation and internal dynamics (sediment availability, cut-and-fill cycles). The site-specific insights are then conceptualized for application to a broader scale. Therefore, a Styria wide database of torrential

  15. Shock events and flood risk management: a media analysis of the institutional long-term effects of flood events in the Netherlands and Poland

    Directory of Open Access Journals (Sweden)

    Maria Kaufmann

    2016-12-01

    Full Text Available Flood events that have proven to create shock waves in society, which we will call shock events, can open windows of opportunity that allow different actor groups to introduce new ideas. Shock events, however, can also strengthen the status quo. We will take flood events as our object of study. Whereas others focus mainly on the immediate impact and disaster management, we will focus on the long-term impact on and resilience of flood risk governance arrangements. Over the last 25 years, both the Netherlands and Poland have suffered several flood-related events. These triggered strategic and institutional changes, but to different degrees. In a comparative analysis these endogenous processes, i.e., the importance of framing of the flood event, its exploitation by different actor groups, and the extent to which arrangements are actually changing, are examined. In line with previous research, our analysis revealed that shock events test the capacity to resist and bounce back and provide opportunities for adapting and learning. They "open up" institutional arrangements and make them more susceptible to change, increasing the opportunity for adaptation. In this way they can facilitate a shift toward different degrees of resilience, i.e., by adjusting the current strategic approach or by moving toward another strategic approach. The direction of change is influenced by the actors and the frames they introduce, and their ability to increase the resonance of the frame. The persistence of change seems to be influenced by the evolution of the initial management approach, the availability of resources, or the willingness to allocate resources.

  16. DETERMINANTS OF INTERNAL VS. EXTERNAL CEO SUCCESSIONS IN MALAYSIAN PUBLIC LISTED COMPANIES

    Directory of Open Access Journals (Sweden)

    Rokiah Ishak

    2012-01-01

    Full Text Available Following a CEO turnover, a company may select an internal or external successor. The objective of this study is to determine if firm performance, board attributes, ownership structure and incumbent power influence the decision of whether to elect an internal or external candidate. Results from logistic regression analysis on 145 succession events over a four-year period (2002 to 2005 indicate that firms which are controlled by blockholders tend to select an outsider as the successor. Further, firms that are controlled by family members and position their former CEOs within the firms are more likely to select insiders as successors. However, firm performance, board composition, CEO duality and turnover type do not affect the selection choice. This study implies that poor firm performance does not necessarily lead to outside CEO selection choice. Further, boards of Malaysian PLCs are not effective in choosing outsiders as successors as both board composition and CEO duality do not necessarily select outsiders to become new CEOs. Another implication of this study is that former CEOs who continue their directorship in the same companies do have some power in naming new CEOs as the former tend to select insiders as successors.

  17. Tsunami Research Status in IAEA after Fukushima Event

    International Nuclear Information System (INIS)

    Kim, Min Kyu; Choi, In Kil

    2012-01-01

    On March 11 th , 2011, a tremendous earthquake and tsunami occurred on the east coast of Japan. This 9.0 magnitude earthquake was the fifth greatest earthquake ever experienced on the planet. The most remarkable problem was that the Fukishima NPP sites. After Japan earthquake, many international researches about tsunami and earthquake event were started or revised. Especially, the most remarkable point of the great earthquake in east coast of Japan was tsunami event. Before this earthquake, the Niigata earthquake occurred in 2007 and the Kashiwazaki Kariwa nuclear power plant had little damaged. The research about the safety of nuclear power plant against earthquake events was activated by 2007 Niigata earthquake. However, the researches about a tsunami event were very few and only tsunami simulation was only focused. After the Fukushima accident, the international society became very interested in tsunami event as a major external event. Therefore in this study, the tsunami research status in IAEA after Fukushima event and the role of Korea are introduced

  18. Elbow joint stability in relation to forced external rotation

    DEFF Research Database (Denmark)

    Deutch, S.R.; Jensen, S.L.; Olsen, B.S.

    2003-01-01

    The objective of this study was to evaluate the osseous constraint related to forced forearm external rotation as the initial stage in a posterior elbow dislocation. Six joint specimens without soft tissues were examined in a joint analysis system developed for simulation of dislocation. The osse......The objective of this study was to evaluate the osseous constraint related to forced forearm external rotation as the initial stage in a posterior elbow dislocation. Six joint specimens without soft tissues were examined in a joint analysis system developed for simulation of dislocation...... external forearm rotation until the point of maximal torque decreased from a maximum in full extension to a minimum at 30 degrees of elbow flexion (P =.03). The elbow in a slightly flexed position, varus stress, and forearm external rotation trauma might be the important biomechanical factors...

  19. Minimization of thermal insulation thickness taking into account condensation on external walls

    Directory of Open Access Journals (Sweden)

    Nurettin Yamankaradeniz

    2015-09-01

    Full Text Available Condensation occurs in the inner layers of construction materials at whatever point the partial pressure of water vapor diffuses and reaches its saturation pressure. Condensation, also called sweating, damages materials, reduces thermal resistance, and by increasing the total heat transfer coefficient, results in unwanted events such as increased heat loss. This study applied minimization of thermal insulation thickness with consideration given to condensation in the external walls. The calculations of heat and mass transfers in the structure elements are expressed in a graphical form. While there was an increase in the required thermal insulation thickness subsequent to an increase in the internal environment’s temperature, relative humidity, and the external environment’s relative humidity, the required thickness decreased with an increase in the external environment’s temperature. The amount of water vapor transferred varied with internal or external conditions and the thickness of the insulation. A change in the vapor diffusion resistance of the insulation material can increase the risk of condensation on the internal or external surfaces of the insulation.

  20. The external sector of the Serbian economy

    Directory of Open Access Journals (Sweden)

    Ristanović Vladimir

    2016-01-01

    Full Text Available The aim of this paper is to show the external sector of the Serbian economy, its features and peculiarities, as well as anomalies that afflicted it for years. In the analysis, data acquired from the Statistical Office of the Republic of Serbia will be used, as well as the official international methodology. The text will include the analysis of the structure of the external sector, market share, competitive position of Serbian economy and export products according to sectors of the economy and factor intensity. Since 2000, the structure of production and exports of the Serbian economy shows low comparative advantages and competitive position throughout the world. Unfavorable structure of the sectors, departments and the product groups affected the deepening of external imbalances and high foreign trade deficit. Exports of technology of predominantly low intensity, resources, and labor-intensive products, common for Serbian economy, represent no guarantee of economic growth in the long term. The causes of external imbalances should be sought in the absence of adequate export strategy, as well as in high speed of liberalization of foreign trade flows and exchange rate policy.

  1. An Initiating-Event Analysis for PSA of Hanul Units 3 and 4: Results and Insights

    International Nuclear Information System (INIS)

    Kim, Dong-San; Park, Jin Hee

    2015-01-01

    As a part of the PSA, an initiating-event (IE) analysis was newly performed by considering the current state of knowledge and the requirements of the ASME/ANS probabilistic risk assessment (PRA) standard related to IE analysis. This paper describes the methods of, results and some insights from the IE analysis for the PSA of the Hanul units 3 and 4. In this study, as a part of the PSA for the Hanul units 3 and 4, an initiating-event (IE) analysis was newly performed by considering the current state of knowledge and the requirements of the ASME/ANS probabilistic risk assessment (PRA) standard. In comparison with the previous IE analysis, this study performed a more systematic and detailed analysis to identify potential initiating events, and calculated the IE frequencies by using the state-of-the-art methods and the latest data. As a result, not a few IE frequencies are quite different from the previous frequencies, which can change the major accident sequences obtained from the quantification of the PSA model

  2. Three-dimensional geometric morphometric analysis of the nasopharyngeal boundaries and its functional integration with the face and external basicranium among extant hominoids.

    Science.gov (United States)

    Pagano, Anthony S; Laitman, Jeffrey T

    2015-01-01

    The nasopharynx is a centrally located but understudied upper respiratory tract component. This study tested hypotheses related to the functional integration of the nasopharyngeal boundaries with the facial skeleton and external basicranium over the course of development in humans and nonhuman hominoids. It was hypothesized that facial morphology (width, length, and kyphosis) is related to nasopharyngeal width and choanal morphology, whereas relative external basicranial proportions are related to nasopharyngeal depth. Human infants were used as models of extreme orthognathy and external basicranial retroflexion, whereas nonhuman hominoids were used to model greater relative prognathism and external basicranial retroflexion. Both of these groups were contrasted against adult humans, who exhibit both extreme orthognathy and external basicranial flexion. Three-dimensional landmark coordinate data were collected from age-graded series of Homo, Pan, Gorilla, Pongo, and Hylobates. Generalized Procrustes Analysis was performed, and multivariate shape differences were evaluated via principal components analysis. Additionally, linear measures were extracted from the Procrustes-corrected sets of landmark data. Results indicate that human adults are indeed distinct from all groups in possessing a relatively shallow nasopharyngeal roof and shorter, more flexed external basicranial axis. Human adults and infants both exhibit greater relative choanal and nasopharyngeal width. Nonhuman hominoid faces tended to become airorhynch into adulthood, whereas humans exhibited the opposite trend. When pooling all the hominoids, facial width and palate length were strongly correlated with choanal and nasopharyngeal width, whereas facial kyphosis was strongly correlated with choanal orientation. The hypotheses were supported as the results indicated a morphologic relationship among nasopharyngeal boundaries, the facial skeleton, and the external basicranium. © 2014 Wiley Periodicals, Inc.

  3. Cognitive moderators of children's adjustment to stressful divorce events: the role of negative cognitive errors and positive illusions.

    Science.gov (United States)

    Mazur, E; Wolchik, S A; Virdin, L; Sandler, I N; West, S G

    1999-01-01

    This study examined whether children's cognitive appraisal biases moderate the impact of stressful divorce-related events on psychological adjustment in 355 children ages 9 to 12, whose families had experienced divorce within the past 2 years. Multiple regression indicated that endorsement of negative cognitive errors for hypothetical divorce events moderates the relations between stressful divorce events and self- and maternal reports of internalizing and externalizing symptoms, but only for older children. Positive illusions buffer the effects of stressful divorce events on child-reported depression and mother-reported externalizing problems. Implications of these results for theories of stress and coping, as well as for interventions for children of divorced families, are discussed.

  4. Erectile dysfunction and cardiovascular events in diabetic men: a meta-analysis of observational studies.

    Directory of Open Access Journals (Sweden)

    Tomohide Yamada

    Full Text Available BACKGROUND: Several studies have shown that erectile dysfunction (ED influences the risk of cardiovascular events (CV events. However, a meta-analysis of the overall risk of CV events associated with ED in patients with diabetes has not been performed. METHODOLOGY/PRINCIPAL FINDINGS: We searched MEDLINE and the Cochrane Library for pertinent articles (including references published between 1951 and April 22, 2012. English language reports of original observational cohort studies and cross-sectional studies were included. Pooled effect estimates were obtained by random effects meta-analysis. A total of 3,791 CV events were reported in 3 cohort studies and 9 cross-sectional studies (covering 22,586 subjects. Across the cohort studies, the overall odds ratio (OR of diabetic men with ED versus those without ED was 1.74 (95% confidence interval [CI]: 1.34-2.27; P0.05. Moreover, meta-regression analysis found no relationship between the method used to assess ED (questionnaire or interview, mean age, mean hemoglobin A(1c, mean body mass index, or mean duration of diabetes and the risk of CV events or CHD. In the cross-sectional studies, the OR of diabetic men with ED versus those without ED was 3.39 (95% CI: 2.58-4.44; P<0.001 for CV events (N = 9, 3.43 (95% CI: 2.46-4.77; P<0.001 for CHD (N = 7, and 2.63 (95% CI: 1.41-4.91; P = 0.002 for peripheral vascular disease (N = 5. CONCLUSION/SIGNIFICANCE: ED was associated with an increased risk of CV events in diabetic patients. Prevention and early detection of cardiovascular disease are important in the management of diabetes, especially in view of the rapid increase in its prevalence.

  5. Short Personality and Life Event scale for detection of suicide attempters.

    Science.gov (United States)

    Artieda-Urrutia, Paula; Delgado-Gómez, David; Ruiz-Hernández, Diego; García-Vega, Juan Manuel; Berenguer, Nuria; Oquendo, Maria A; Blasco-Fontecilla, Hilario

    2015-01-01

    To develop a brief and reliable psychometric scale to identify individuals at risk for suicidal behaviour. Case-control study. 182 individuals (61 suicide attempters, 57 psychiatric controls, and 64 psychiatrically healthy controls) aged 18 or older, admitted to the Emergency Department at Puerta de Hierro University Hospital in Madrid, Spain. All participants completed a form including their socio-demographic and clinical characteristics, and the Personality and Life Events scale (27 items). To assess Axis I diagnoses, all psychiatric patients (including suicide attempters) were administered the Mini International Neuropsychiatric Interview. Descriptive statistics were computed for the socio-demographic factors. Additionally, χ(2) independence tests were applied to evaluate differences in socio-demographic and clinical variables, and the Personality and Life Events scale between groups. A stepwise linear regression with backward variable selection was conducted to build the Short Personality Life Event (S-PLE) scale. In order to evaluate the accuracy, a ROC analysis was conducted. The internal reliability was assessed using Cronbach's α, and the external reliability was evaluated using a test-retest procedure. The S-PLE scale, composed of just 6 items, showed good performance in discriminating between medical controls, psychiatric controls and suicide attempters in an independent sample. For instance, the S-PLE scale discriminated between past suicide and past non-suicide attempters with sensitivity of 80% and specificity of 75%. The area under the ROC curve was 88%. A factor analysis extracted only one factor, revealing a single dimension of the S-PLE scale. Furthermore, the S-PLE scale provides values of internal and external reliability between poor (test-retest: 0.55) and acceptable (Cronbach's α: 0.65) ranges. Administration time is about one minute. The S-PLE scale is a useful and accurate instrument for estimating the risk of suicidal behaviour in

  6. Nonlinear Analysis of the Space Shuttle Superlightweight External Fuel Tank

    Science.gov (United States)

    Nemeth, Michael P.; Britt, Vicki O.; Collins, Timothy J.; Starnes, James H., Jr.

    1996-01-01

    Results of buckling and nonlinear analyses of the Space Shuttle external tank superlightweight liquid-oxygen (LO2) tank are presented. Modeling details and results are presented for two prelaunch loading conditions and for two full-scale structural tests that were conducted on the original external tank. The results illustrate three distinctly different types of nonlinear response for thin-walled shells subjected to combined mechanical and thermal loads. The nonlinear response phenomena consist of bifurcation-type buckling, short-wavelength nonlinear bending, and nonlinear collapse associated with a limit point. For each case, the results show that accurate predictions of non- linear behavior generally require a large-scale, high-fidelity finite-element model. Results are also presented that show that a fluid-filled launch-vehicle shell can be highly sensitive to initial geometric imperfections. In addition, results presented for two full-scale structural tests of the original standard-weight external tank suggest that the finite-element modeling approach used in the present study is sufficient for representing the nonlinear behavior of the superlightweight LO2 tank.

  7. Recurring events - Volume 2

    International Nuclear Information System (INIS)

    2003-04-01

    known, thus the actions taken were not effective in preventing recurrence of an event, - The contributing factors or causes of the event were not taken into account in defining the actions to be taken. Several good practices were identified to prevent recurring events. These practices are part of related guides provided by national and international bodies. Some of these are: - NPPs should analyse recurring events in-depth, in order to identify root causes and contributing factors to prevent further recurrence. The specific factors that failed to prevent recurrence should be investigated and identified (that is, why prior operating experience was not effectively applied). - For minor events, trend analyses should be performed to monitor the frequency of component failures (which may be unavoidable) or the frequency of minor human performance problems (which may indicate weaknesses in error prevention processes and programs). - Analysis of external operating experiences from other NPPs should be strengthened to broaden the basis for preventive measures; - Actions taken after events should be assessed regarding their effectiveness in preventing recurrence of similar events. Subsequent to the workshop, a more detailed search of reports of operating experience, including IRS and other reports from national sources, resulted in the determination of a number of recurring categories: - Loss of RHR at mid-loop (in the 1999 report also); - BWR instability (in the 1999 report also); - PWR vessel corrosion due to boric acid effects; - Hydrogen detonation in BWR piping; - Steam Generator Tube Rupture; - Multiple valve failures in ECCS; - Service Water Failure due to Marine Biofouling (in the 1999 report also); - System Level Failures with Human Factors Considerations; - Strainer Clogging (sources of emergency injection or recirculation). Five conclusions were established on the basis of the workshop and the recurring event analysis: Conclusion 1: Recurring events continue to be

  8. Intermittent ice sheet discharge events in northeastern North America during the last glacial period

    Energy Technology Data Exchange (ETDEWEB)

    Papa, Brian D.; Mysak, Lawrence A.; Wang, Zhaomin [McGill University, Earth System Modelling Group, Department of Atmospheric and Oceanic Sciences, Montreal, QC (Canada)

    2006-02-01

    The 3D ice sheet model of Marshall and Clarke, which includes both dynamics and thermodynamics, is used to successfully simulate millennial-scale oscillations within an ice sheet under steady external forcing. Such internal oscillations are theorized to be the main cause of quasi-periodic large-scale ice discharges known as Heinrich Events. An analysis of the mechanisms associated with multi-millennial oscillations of the Laurentide Ice Sheet, including the initiation and termination of sliding events, is performed. This analysis involves an examination of the various heat sources and sinks that affect the basal ice temperature, which in turn determines the nature of the ice sheet movement. The ice sheet thickness and surface slope, which affect the pressure-melting point and strain heating, respectively, are found to be critical for the formation and development of fast moving ice streams, which lead to large iceberg calving. Although the main provenance for Heinrich Events is thought to be from Hudson Bay and Hudson Strait, we show that the more northerly regions around Lancaster Strait and Baffin Island may also be important sources for ice discharges during the last glacial period. (orig.)

  9. Procedure for conducting probabilistic safety assessment: level 1 full power internal event analysis

    Energy Technology Data Exchange (ETDEWEB)

    Jung, Won Dae; Lee, Y. H.; Hwang, M. J. [and others

    2003-07-01

    This report provides guidance on conducting a Level I PSA for internal events in NPPs, which is based on the method and procedure that was used in the PSA for the design of Korea Standard Nuclear Plants (KSNPs). Level I PSA is to delineate the accident sequences leading to core damage and to estimate their frequencies. It has been directly used for assessing and modifying the system safety and reliability as a key and base part of PSA. Also, Level I PSA provides insights into design weakness and into ways of preventing core damage, which in most cases is the precursor to accidents leading to major accidents. So Level I PSA has been used as the essential technical bases for risk-informed application in NPPs. The report consists six major procedural steps for Level I PSA; familiarization of plant, initiating event analysis, event tree analysis, system fault tree analysis, reliability data analysis, and accident sequence quantification. The report is intended to assist technical persons performing Level I PSA for NPPs. A particular aim is to promote a standardized framework, terminology and form of documentation for PSAs. On the other hand, this report would be useful for the managers or regulatory persons related to risk-informed regulation, and also for conducting PSA for other industries.

  10. An experimental investigation of masking in the US FDA adverse event reporting system database.

    Science.gov (United States)

    Wang, Hsin-wei; Hochberg, Alan M; Pearson, Ronald K; Hauben, Manfred

    2010-12-01

    A phenomenon of 'masking' or 'cloaking' in pharmacovigilance data mining has been described, which can potentially cause signals of disproportionate reporting (SDRs) to be missed, particularly in pharmaceutical company databases. Masking has been predicted theoretically, observed anecdo