Science.gov

Sample records for accident analysis techniques

  1. Developing techniques for cause-responsibility analysis of occupational accidents.

    PubMed

    Jabbari, Mousa; Ghorbani, Roghayeh

    2016-11-01

    The aim of this study was to specify the causes of occupational accidents, determine social responsibility and the role of groups involved in work-related accidents. This study develops occupational accidents causes tree, occupational accidents responsibility tree, and occupational accidents component-responsibility analysis worksheet; based on these methods, it develops cause-responsibility analysis (CRA) techniques, and for testing them, analyzes 100 fatal/disabling occupational accidents in the construction setting that were randomly selected from all the work-related accidents in Tehran, Iran, over a 5-year period (2010-2014). The main result of this study involves two techniques for CRA: occupational accidents tree analysis (OATA) and occupational accidents components analysis (OACA), used in parallel for determination of responsible groups and responsibilities rate. From the results, we find that the management group of construction projects has 74.65% responsibility of work-related accidents. The developed techniques are purposeful for occupational accidents investigation/analysis, especially for the determination of detailed list of tasks, responsibilities, and their rates. Therefore, it is useful for preventing work-related accidents by focusing on the responsible group's duties.

  2. Implementation of numerical simulation techniques in analysis of the accidents in complex technological systems

    SciTech Connect

    Klishin, G.S.; Seleznev, V.E.; Aleoshin, V.V.

    1997-12-31

    Gas industry enterprises such as main pipelines, compressor gas transfer stations, gas extracting complexes belong to the energy intensive industry. Accidents there can result into the catastrophes and great social, environmental and economic losses. Annually, according to the official data several dozens of large accidents take place at the pipes in the USA and Russia. That is why prevention of the accidents, analysis of the mechanisms of their development and prediction of their possible consequences are acute and important tasks nowadays. The accidents reasons are usually of a complicated character and can be presented as a complex combination of natural, technical and human factors. Mathematical and computer simulations are safe, rather effective and comparatively inexpensive methods of the accident analysis. It makes it possible to analyze different mechanisms of a failure occurrence and development, to assess its consequences and give recommendations to prevent it. Besides investigation of the failure cases, numerical simulation techniques play an important role in the treatment of the diagnostics results of the objects and in further construction of mathematical prognostic simulations of the object behavior in the period of time between two inspections. While solving diagnostics tasks and in the analysis of the failure cases, the techniques of theoretical mechanics, of qualitative theory of different equations, of mechanics of a continuous medium, of chemical macro-kinetics and optimizing techniques are implemented in the Conversion Design Bureau {number_sign}5 (DB{number_sign}5). Both universal and special numerical techniques and software (SW) are being developed in DB{number_sign}5 for solution of such tasks. Almost all of them are calibrated on the calculations of the simulated and full-scale experiments performed at the VNIIEF and MINATOM testing sites. It is worth noting that in the long years of work there has been established a fruitful and effective

  3. A Flexible Hierarchical Bayesian Modeling Technique for Risk Analysis of Major Accidents.

    PubMed

    Yu, Hongyang; Khan, Faisal; Veitch, Brian

    2017-02-28

    Safety analysis of rare events with potentially catastrophic consequences is challenged by data scarcity and uncertainty. Traditional causation-based approaches, such as fault tree and event tree (used to model rare event), suffer from a number of weaknesses. These include the static structure of the event causation, lack of event occurrence data, and need for reliable prior information. In this study, a new hierarchical Bayesian modeling based technique is proposed to overcome these drawbacks. The proposed technique can be used as a flexible technique for risk analysis of major accidents. It enables both forward and backward analysis in quantitative reasoning and the treatment of interdependence among the model parameters. Source-to-source variability in data sources is also taken into account through a robust probabilistic safety analysis. The applicability of the proposed technique has been demonstrated through a case study in marine and offshore industry.

  4. Practical approaches in accident analysis

    NASA Astrophysics Data System (ADS)

    Stock, M.

    An accident analysis technique based on successive application of structural response, explosion dynamics, gas cloud formation, and plant operation failure mode models is proposed. The method takes into account the nonideal explosion characteristic of a deflagration in the unconfined cloud. The resulting pressure wave differs significantly from a shock wave and the response of structures like lamp posts and walls can differ correspondingly. This gives a more realistic insight into explosion courses than a simple TNT-equivalent approach.

  5. Applying STAMP in Accident Analysis

    NASA Technical Reports Server (NTRS)

    Leveson, Nancy; Daouk, Mirna; Dulac, Nicolas; Marais, Karen

    2003-01-01

    Accident models play a critical role in accident investigation and analysis. Most traditional models are based on an underlying chain of events. These models, however, have serious limitations when used for complex, socio-technical systems. Previously, Leveson proposed a new accident model (STAMP) based on system theory. In STAMP, the basic concept is not an event but a constraint. This paper shows how STAMP can be applied to accident analysis using three different views or models of the accident process and proposes a notation for describing this process.

  6. A novel technique for disruption simulation and accident analysis using an ET plasma source

    SciTech Connect

    Sharpe, J.P.; Bourham, M.A.; Gilligan, J.G.

    1997-12-31

    In order to generate defensible safety analyses for future tokamak reactors, disruption effects on plasma-facing materials and subsequent aerosol formation mechanisms must be well understood and benchmarked with a relevant database. One technique for disruption simulation involves the use of an electrothermal (ET) plasma source. The ET facility SIRENS at North Carolina State University has been modified to study disruption-induced aerosol mobilization for ITER relevant materials. Particle transport properties obtained from experiments will contribute to a materials database for use in ITER safety analysis. Electrothermal plasma sources have been used to simulate disruptions because magnitudes and physical mechanisms of heat transfer in the ET source are very similar to those in a disruption. However, to study vaporization and subsequent condensation of plasma-exposed surfaces requires modifications to the ET source. This paper describes the necessary modifications to SIRENS and provides a physical and parametric comparison of the experiment and its relevance to disruption mobilization in ITER.

  7. Severe accident analysis using dynamic accident progression event trees

    NASA Astrophysics Data System (ADS)

    Hakobyan, Aram P.

    In present, the development and analysis of Accident Progression Event Trees (APETs) are performed in a manner that is computationally time consuming, difficult to reproduce and also can be phenomenologically inconsistent. One of the principal deficiencies lies in the static nature of conventional APETs. In the conventional event tree techniques, the sequence of events is pre-determined in a fixed order based on the expert judgments. The main objective of this PhD dissertation was to develop a software tool (ADAPT) for automated APET generation using the concept of dynamic event trees. As implied by the name, in dynamic event trees the order and timing of events are determined by the progression of the accident. The tool determines the branching times from a severe accident analysis code based on user specified criteria for branching. It assigns user specified probabilities to every branch, tracks the total branch probability, and truncates branches based on the given pruning/truncation rules to avoid an unmanageable number of scenarios. The function of a dynamic APET developed includes prediction of the conditions, timing, and location of containment failure or bypass leading to the release of radioactive material, and calculation of probabilities of those failures. Thus, scenarios that can potentially lead to early containment failure or bypass, such as through accident induced failure of steam generator tubes, are of particular interest. Also, the work is focused on treatment of uncertainties in severe accident phenomena such as creep rupture of major RCS components, hydrogen burn, containment failure, timing of power recovery, etc. Although the ADAPT methodology (Analysis of Dynamic Accident Progression Trees) could be applied to any severe accident analysis code, in this dissertation the approach is demonstrated by applying it to the MELCOR code [1]. A case study is presented involving station blackout with the loss of auxiliary feedwater system for a

  8. A Look at Aircraft Accident Analysis in the Early Days: Do Early 20th Century Accident Investigation Techniques Have Any Lessons for Today?

    NASA Technical Reports Server (NTRS)

    Holloway, C. M.; Johnson, C. W.

    2007-01-01

    In the early years of powered flight, the National Advisory Committee on Aeronautics in the United States produced three reports describing a method of analysis of aircraft accidents. The first report was published in 1928; the second, which was a revision of the first, was published in 1930; and the third, which was a revision and update of the second, was published in 1936. This paper describes the contents of these reports, and compares the method of analysis proposed therein to the methods used today.

  9. Mitigative techniques and analysis of generic site conditions for ground-water contamination associated with severe accidents

    SciTech Connect

    Shafer, J.M.; Oberlander, P.L.; Skaggs, R.L.

    1984-04-01

    The purpose of this study is to evaluate the feasibility of using ground-water contaminant mitigation techniques to control radionuclide migration following a severe commercial nuclear power reactor accident. The two types of severe commercial reactor accidents investigated are: (1) containment basemat penetration of core melt debris which slowly cools and leaches radionuclides to the subsurface environment, and (2) containment basemat penetration of sump water without full penetration of the core mass. Six generic hydrogeologic site classifications are developed from an evaluation of reported data pertaining to the hydrogeologic properties of all existing and proposed commercial reactor sites. One-dimensional radionuclide transport analyses are conducted on each of the individual reactor sites to determine the generic characteristics of a radionuclide discharge to an accessible environment. Ground-water contaminant mitigation techniques that may be suitable, depending on specific site and accident conditions, for severe power plant accidents are identified and evaluated. Feasible mitigative techniques and associated constraints on feasibility are determined for each of the six hydrogeologic site classifications. The first of three case studies is conducted on a site located on the Texas Gulf Coastal Plain. Mitigative strategies are evaluated for their impact on contaminant transport and results show that the techniques evaluated significantly increased ground-water travel times. 31 references, 118 figures, 62 tables.

  10. Aircraft accidents : method of analysis

    NASA Technical Reports Server (NTRS)

    1931-01-01

    The revised report includes the chart for the analysis of aircraft accidents, combining consideration of the immediate causes, underlying causes, and results of accidents, as prepared by the special committee, with a number of the definitions clarified. A brief statement of the organization and work of the special committee and of the Committee on Aircraft Accidents; and statistical tables giving a comparison of the types of accidents and causes of accidents in the military services on the one hand and in civil aviation on the other, together with explanations of some of the important differences noted in these tables.

  11. Accident Tolerant Fuel Analysis

    SciTech Connect

    Smith, Curtis; Chichester, Heather; Johns, Jesse; Teague, Melissa; Tonks, Michael; Youngblood, Robert

    2014-09-01

    Safety is central to the design, licensing, operation, and economics of Nuclear Power Plants (NPPs). Consequently, the ability to better characterize and quantify safety margin holds the key to improved decision making about light water reactor design, operation, and plant life extension. A systematic approach to characterization of safety margins and the subsequent margins management options represents a vital input to the licensee and regulatory analysis and decision making that will be involved. The purpose of the Risk Informed Safety Margin Characterization (RISMC) Pathway research and development (R&D) is to support plant decisions for risk-informed margins management by improving economics and reliability, and sustaining safety, of current NPPs. Goals of the RISMC Pathway are twofold: (1) Develop and demonstrate a risk-assessment method coupled to safety margin quantification that can be used by NPP decision makers as part of their margin recovery strategies. (2) Create an advanced “RISMC toolkit” that enables more accurate representation of NPP safety margin. In order to carry out the R&D needed for the Pathway, the Idaho National Laboratory is performing a series of case studies that will explore methods- and tools-development issues, in addition to being of current interest in their own right. One such study is a comparative analysis of safety margins of plants using different fuel cladding types: specifically, a comparison between current-technology Zircaloy cladding and a notional “accident-tolerant” (e.g., SiC-based) cladding. The present report begins the process of applying capabilities that are still under development to the problem of assessing new fuel designs. The approach and lessons learned from this case study will be included in future Technical Basis Guides produced by the RISMC Pathway. These guides will be the mechanism for developing the specifications for RISMC tools and for defining how plant decision makers should propose and

  12. Aircraft accidents : method of analysis

    NASA Technical Reports Server (NTRS)

    1929-01-01

    This report on a method of analysis of aircraft accidents has been prepared by a special committee on the nomenclature, subdivision, and classification of aircraft accidents organized by the National Advisory Committee for Aeronautics in response to a request dated February 18, 1928, from the Air Coordination Committee consisting of the Assistant Secretaries for Aeronautics in the Departments of War, Navy, and Commerce. The work was undertaken in recognition of the difficulty of drawing correct conclusions from efforts to analyze and compare reports of aircraft accidents prepared by different organizations using different classifications and definitions. The air coordination committee's request was made "in order that practices used may henceforth conform to a standard and be universally comparable." the purpose of the special committee therefore was to prepare a basis for the classification and comparison of aircraft accidents, both civil and military. (author)

  13. Techniques and Tools of NASA's Space Shuttle Columbia Accident Investigation

    NASA Technical Reports Server (NTRS)

    McDanels, Steve J.

    2005-01-01

    The Space Shuttle Columbia accident investigation was a fusion of many disciplines into a single effort. From the recovery and reconstruction of the debris, Figure 1, to the analysis, both destructive and nondestructive, of chemical and metallurgical samples, Figure 2, a multitude of analytical techniques and tools were employed. Destructive and non-destructive testing were utilized in tandem to determine if a breach in the left wing of the Orbiter had occurred, and if so, the path of the resultant high temperature plasma flow. Nondestructive analysis included topometric scanning, laser mapping, and real-time radiography. These techniques were useful in constructing a three dimensional virtual representation of the reconstruction project, specifically the left wing leading edge reinforced carbon/carbon heat protectant panels. Similarly, they were beneficial in determining where sampling should be performed on the debris. Analytic testing included such techniques as Energy Dispersive Electron Microprobe Analysis (EMPA), Electron Spectroscopy Chemical Analysis (ESCA), and X-Ray dot mapping; these techniques related the characteristics of intermetallics deposited on the leading edge of the left wing adjacent to the location of a suspected plasma breach during reentry. The methods and results of the various analyses, along with their implications into the accident, are discussed, along with the findings and recommendations of the Columbia Accident Investigation Board. Likewise, NASA's Return To Flight efforts are highlighted.

  14. Nuclear fuel cycle facility accident analysis handbook

    SciTech Connect

    Ayer, J E; Clark, A T; Loysen, P; Ballinger, M Y; Mishima, J; Owczarski, P C; Gregory, W S; Nichols, B D

    1988-05-01

    The Accident Analysis Handbook (AAH) covers four generic facilities: fuel manufacturing, fuel reprocessing, waste storage/solidification, and spent fuel storage; and six accident types: fire, explosion, tornado, criticality, spill, and equipment failure. These are the accident types considered to make major contributions to the radiological risk from accidents in nuclear fuel cycle facility operations. The AAH will enable the user to calculate source term releases from accident scenarios manually or by computer. A major feature of the AAH is development of accident sample problems to provide input to source term analysis methods and transport computer codes. Sample problems and illustrative examples for different accident types are included in the AAH.

  15. Single pilot IFR accident data analysis

    NASA Technical Reports Server (NTRS)

    Harris, D. F.

    1983-01-01

    The aircraft accident data recorded by the National Transportation and Safety Board (NTSR) for 1964-1979 were analyzed to determine what problems exist in the general aviation (GA) single pilot instrument flight rule (SPIFR) environment. A previous study conducted in 1978 for the years 1964-1975 provided a basis for comparison. This effort was generally limited to SPIFR pilot error landing phase accidents but includes some SPIFR takeoff and enroute accident analysis as well as some dual pilot IFR accident analysis for comparison. Analysis was performed for 554 accidents of which 39% (216) occurred during the years 1976-1979.

  16. An analysis of fishing vessel accidents.

    PubMed

    Wang, J; Pillay, A; Kwon, Y S; Wall, A D; Loughran, C G

    2005-11-01

    In this paper, accident data collected from the Marine Accident Investigation Branch are presented and an analysis is carried out to determine the most common causes of accidents on fishing vessels. Discussions on fishing vessel-safety assessment and data problems are given.

  17. Industrial accidents triggered by flood events: analysis of past accidents.

    PubMed

    Cozzani, Valerio; Campedel, Michela; Renni, Elisabetta; Krausmann, Elisabeth

    2010-03-15

    Industrial accidents triggered by natural events (NaTech accidents) are a significant category of industrial accidents. Several specific elements that characterize NaTech events still need to be investigated. In particular, the damage mode of equipment and the specific final scenarios that may take place in NaTech accidents are key elements for the assessment of hazard and risk due to these events. In the present study, data on 272 NaTech events triggered by floods were retrieved from some of the major industrial accident databases. Data on final scenarios highlighted the presence of specific events, as those due to substances reacting with water, and the importance of scenarios involving consequences for the environment. This is mainly due to the contamination of floodwater with the hazardous substances released. The analysis of process equipment damage modes allowed the identification of the expected release extents due to different water impact types during floods. The results obtained were used to generate substance-specific event trees for the quantitative assessment of the consequences of accidents triggered by floods.

  18. An analysis of pilot error-related aircraft accidents

    NASA Technical Reports Server (NTRS)

    Kowalsky, N. B.; Masters, R. L.; Stone, R. B.; Babcock, G. L.; Rypka, E. W.

    1974-01-01

    A multidisciplinary team approach to pilot error-related U.S. air carrier jet aircraft accident investigation records successfully reclaimed hidden human error information not shown in statistical studies. New analytic techniques were developed and applied to the data to discover and identify multiple elements of commonality and shared characteristics within this group of accidents. Three techniques of analysis were used: Critical element analysis, which demonstrated the importance of a subjective qualitative approach to raw accident data and surfaced information heretofore unavailable. Cluster analysis, which was an exploratory research tool that will lead to increased understanding and improved organization of facts, the discovery of new meaning in large data sets, and the generation of explanatory hypotheses. Pattern recognition, by which accidents can be categorized by pattern conformity after critical element identification by cluster analysis.

  19. Aircraft Loss-of-Control Accident Analysis

    NASA Technical Reports Server (NTRS)

    Belcastro, Christine M.; Foster, John V.

    2010-01-01

    Loss of control remains one of the largest contributors to fatal aircraft accidents worldwide. Aircraft loss-of-control accidents are complex in that they can result from numerous causal and contributing factors acting alone or (more often) in combination. Hence, there is no single intervention strategy to prevent these accidents. To gain a better understanding into aircraft loss-of-control events and possible intervention strategies, this paper presents a detailed analysis of loss-of-control accident data (predominantly from Part 121), including worst case combinations of causal and contributing factors and their sequencing. Future potential risks are also considered.

  20. Learning from Accident Analysis: The Dynamics Leading Up to a Rafting Accident.

    ERIC Educational Resources Information Center

    Hovelynck, Johan

    1998-01-01

    Analysis of a case study of a whitewater rafting accident reveals that such accidents tend to result from multiple actions. Many events leading up to such accidents include procedural and process factors, suggesting that hard-skills technical training is an insufficient approach to accident prevention. Contains 26 references. (SAS)

  1. MELCOR analysis of the TMI-2 accident

    SciTech Connect

    Boucheron, E.A.

    1990-01-01

    This paper describes the analysis of the Three Mile Island-2 (TMI-2) standard problem that was performed with MELCOR. The MELCOR computer code is being developed by Sandia National Laboratories for the Nuclear Regulatory Commission for the purpose of analyzing severe accident in nuclear power plants. The primary role of MELCOR is to provide realistic predictions of severe accident phenomena and the radiological source team. The analysis of the TMI-2 standard problem allowed for comparison of the model predictions in MELCOR to plant data and to the results of more mechanistic analyses. This exercise was, therefore valuable for verifying and assessing the models in the code. The major trends in the TMI-2 accident are reasonably well predicted with MELCOR, even with its simplified modeling. Comparison of the calculated and measured results is presented and, based on this comparison, conclusions can be drawn concerning the applicability of MELCOR to severe accident analysis. 5 refs., 10 figs., 3 tabs.

  2. An analysis of aircraft accidents involving fires

    NASA Technical Reports Server (NTRS)

    Lucha, G. V.; Robertson, M. A.; Schooley, F. A.

    1975-01-01

    All U. S. Air Carrier accidents between 1963 and 1974 were studied to assess the extent of total personnel and aircraft damage which occurred in accidents and in accidents involving fire. Published accident reports and NTSB investigators' factual backup files were the primary sources of data. Although it was frequently not possible to assess the relative extent of fire-caused damage versus impact damage using the available data, the study established upper and lower bounds for deaths and damage due specifically to fire. In 12 years there were 122 accidents which involved airframe fires. Eighty-seven percent of the fires occurred after impact, and fuel leakage from ruptured tanks or severed lines was the most frequently cited cause. A cost analysis was performed for 300 serious accidents, including 92 serious accidents which involved fire. Personal injury costs were outside the scope of the cost analysis, but data on personnel injury judgements as well as settlements received from the CAB are included for reference.

  3. A Technique for Showing Causal Arguments in Accident Reports

    NASA Technical Reports Server (NTRS)

    Holloway, C. M.; Johnson, C. W.

    2005-01-01

    In the prototypical accident report, specific findings, particularly those related to causes and contributing factors, are usually written out explicitly and clearly. Also, the evidence upon which these findings are based is typically explained in detail. Often lacking, however, is any explicit discussion, description, or depiction of the arguments that connect the findings and the evidence. That is, the reports do not make clear why the investigators believe that the specific evidence they found necessarily leads to the particular findings they enumerated. This paper shows how graphical techniques can be used to depict relevant arguments supporting alternate positions on the causes of a complex road-traffic accident.

  4. Safety analysis of surface haulage accidents

    SciTech Connect

    Randolph, R.F.; Boldt, C.M.K.

    1996-12-31

    Research on improving haulage truck safety, started by the U.S. Bureau of Mines, is being continued by its successors. This paper reports the orientation of the renewed research efforts, beginning with an update on accident data analysis, the role of multiple causes in these accidents, and the search for practical methods for addressing the most important causes. Fatal haulage accidents most often involve loss of control or collisions caused by a variety of factors. Lost-time injuries most often involve sprains or strains to the back or multiple body areas, which can often be attributed to rough roads and the shocks of loading and unloading. Research to reduce these accidents includes improved warning systems, shock isolation for drivers, encouraging seatbelt usage, and general improvements to system and task design.

  5. Anthropotechnological analysis of industrial accidents in Brazil.

    PubMed Central

    Binder, M. C.; de Almeida, I. M.; Monteau, M.

    1999-01-01

    The Brazilian Ministry of Labour has been attempting to modify the norms used to analyse industrial accidents in the country. For this purpose, in 1994 it tried to make compulsory use of the causal tree approach to accident analysis, an approach developed in France during the 1970s, without having previously determined whether it is suitable for use under the industrial safety conditions that prevail in most Brazilian firms. In addition, opposition from Brazilian employers has blocked the proposed changes to the norms. The present study employed anthropotechnology to analyse experimental application of the causal tree method to work-related accidents in industrial firms in the region of Botucatu, São Paulo. Three work-related accidents were examined in three industrial firms representative of local, national and multinational companies. On the basis of the accidents analysed in this study, the rationale for the use of the causal tree method in Brazil can be summarized for each type of firm as follows: the method is redundant if there is a predominance of the type of risk whose elimination or neutralization requires adoption of conventional industrial safety measures (firm representative of local enterprises); the method is worth while if the company's specific technical risks have already largely been eliminated (firm representative of national enterprises); and the method is particularly appropriate if the firm has a good safety record and the causes of accidents are primarily related to industrial organization and management (multinational enterprise). PMID:10680249

  6. Single pilot IFR accident data analysis

    NASA Technical Reports Server (NTRS)

    Harris, D. F.; Morrisete, J. A.

    1982-01-01

    The aircraft accident data recorded and maintained by the National Transportation Safety Board for 1964 to 1979 were analyzed to determine what problems exist in the general aviation single pilot instrument flight rules environment. A previous study conducted in 1978 for the years 1964 to 1975 provided a basis for comparison. The purpose was to determine what changes, if any, have occurred in trends and cause-effect relationships reported in the earlier study. The increasing numbers have been tied to measures of activity to produce accident rates which in turn were analyzed in terms of change. Where anomalies or unusually high accident rates were encountered, further analysis was conducted to isolate pertinent patterns of cause factors and/or experience levels of involved pilots. The bulk of the effort addresses accidents in the landing phase of operations. A detailed analysis was performed on controlled/uncontrolled collisions and their unique attributes delineated. Estimates of day vs. night general aviation activity and accident rates were obtained.

  7. [Hanggliding accidents. Distribution of injuries and accident analysis].

    PubMed

    Ballmer, F T; Jakob, R P

    1989-12-01

    Paragliding--a relatively new sport to Switzerland--brought 23 patients with 48 injuries (38% lower limb and 29% spinal) within a period of 8 months to the Inselspital University hospital in Berne. The aim of the study in characterizing these injuries is to formulate some guidelines towards prevention. With over 90% of accidents occurring at either take off or landing, emphasis on better training for the beginner is proposed with strict guidelines for the more experienced pilot flying in unfavourable conditions.

  8. Canister Storage Building (CSB) Design Basis Accident Analysis Documentation

    SciTech Connect

    CROWE, R.D.

    1999-09-09

    This document provides the detailed accident analysis to support ''HNF-3553, Spent Nuclear Fuel Project Final Safety, Analysis Report, Annex A,'' ''Canister Storage Building Final Safety Analysis Report.'' All assumptions, parameters, and models used to provide the analysis of the design basis accidents are documented to support the conclusions in the Canister Storage Building Final Safety Analysis Report.

  9. Canister Storage Building (CSB) Design Basis Accident Analysis Documentation

    SciTech Connect

    CROWE, R.D.; PIEPHO, M.G.

    2000-03-23

    This document provided the detailed accident analysis to support HNF-3553, Spent Nuclear Fuel Project Final Safety Analysis Report, Annex A, ''Canister Storage Building Final Safety Analysis Report''. All assumptions, parameters, and models used to provide the analysis of the design basis accidents are documented to support the conclusions in the Canister Storage Building Final Safety Analysis Report.

  10. Canister storage building design basis accident analysis documentation

    SciTech Connect

    KOPELIC, S.D.

    1999-02-25

    This document provides the detailed accident analysis to support HNF-3553, Spent Nuclear Fuel Project Final Safety Analysis Report, Annex A, ''Canister Storage Building Final Safety Analysis Report.'' All assumptions, parameters, and models used to provide the analysis of the design basis accidents are documented to support the conclusions in the Canister Storage Building Final Safety Analysis Report.

  11. Cold Vacuum Drying (CVD) Facility Design Basis Accident Analysis Documentation

    SciTech Connect

    PIEPHO, M.G.

    1999-10-20

    This document provides the detailed accident analysis to support HNF-3553, Annex B, Spent Nuclear Fuel Project Final Safety Analysis Report, ''Cold Vacuum Drying Facility Final Safety Analysis Report (FSAR).'' All assumptions, parameters and models used to provide the analysis of the design basis accidents are documented to support the conclusions in the FSAR.

  12. Reactor Safety Gap Evaluation of Accident Tolerant Components and Severe Accident Analysis

    SciTech Connect

    Farmer, Mitchell T.; Bunt, R.; Corradini, M.; Ellison, Paul B.; Francis, M.; Gabor, John D.; Gauntt, R.; Henry, C.; Linthicum, R.; Luangdilok, W.; Lutz, R.; Paik, C.; Plys, M.; Rabiti, Cristian; Rempe, J.; Robb, K.; Wachowiak, R.

    2015-01-31

    The overall objective of this study was to conduct a technology gap evaluation on accident tolerant components and severe accident analysis methodologies with the goal of identifying any data and/or knowledge gaps that may exist, given the current state of light water reactor (LWR) severe accident research, and additionally augmented by insights obtained from the Fukushima accident. The ultimate benefit of this activity is that the results can be used to refine the Department of Energy’s (DOE) Reactor Safety Technology (RST) research and development (R&D) program plan to address key knowledge gaps in severe accident phenomena and analyses that affect reactor safety and that are not currently being addressed by the industry or the Nuclear Regulatory Commission (NRC).

  13. [An analysis of industrial accidents in the working field with a particular emphasis on repeated accidents].

    PubMed

    Wakisaka, I; Yanagihashi, T; Tomari, T; Sato, M

    1990-03-01

    The present study is based on an analysis of routinely submitted reports of occupational accidents experienced by the workers of industrial enterprises under the jurisdiction of Kagoshima Labor Standard Office during a 5-year period 1983 to 1987. Officially notified injuries serious enough to keep employees away from their job for work at least 4 days were utilized in this study. Data was classified so as to give an observed frequency distribution for workers having any specified number of accidents. Also, the accident rate which is an indicator of the risk of accident was compared among different occupations, between age groups and between the sexes. Results obtained are as follows; 1) For the combined total of 6,324 accident cases for 8 types of occupation (Construction, Transportation, Mining & Quarrying, Forestry, Food manufacture, Lumber & Woodcraft, Manufacturing industry and Other business), the number of those who had at least one accident was 6,098, of which 5,837 were injured only once, 208 twice, 21 three times and 2 four times. When occupation type was fixed, however, the number of workers having one, two, three and four times of accidents were 5,895, 182, 19 and 2, respectively. This suggests that some workers are likely to have experienced repeated accidents in more than one type of occupation.(ABSTRACT TRUNCATED AT 250 WORDS)

  14. Accident progression event tree analysis for postulated severe accidents at N Reactor

    SciTech Connect

    Wyss, G.D.; Camp, A.L.; Miller, L.A.; Dingman, S.E.; Kunsman, D.M. ); Medford, G.T. )

    1990-06-01

    A Level II/III probabilistic risk assessment (PRA) has been performed for N Reactor, a Department of Energy (DOE) production reactor located on the Hanford reservation in Washington. The accident progression analysis documented in this report determines how core damage accidents identified in the Level I PRA progress from fuel damage to confinement response and potential releases the environment. The objectives of the study are to generate accident progression data for the Level II/III PRA source term model and to identify changes that could improve plant response under accident conditions. The scope of the analysis is comprehensive, excluding only sabotage and operator errors of commission. State-of-the-art methodology is employed based largely on the methods developed by Sandia for the US Nuclear Regulatory Commission in support of the NUREG-1150 study. The accident progression model allows complex interactions and dependencies between systems to be explicitly considered. Latin Hypecube sampling was used to assess the phenomenological and systemic uncertainties associated with the primary and confinement system responses to the core damage accident. The results of the analysis show that the N Reactor confinement concept provides significant radiological protection for most of the accident progression pathways studied.

  15. Criticality accident dosimetry by chromosomal analysis.

    PubMed

    Voisin, P; Roy, L; Hone, P A; Edwards, A A; Lloyd, D C; Stephan, G; Romm, H; Groer, P G; Brame, R

    2004-01-01

    The technique of measuring the frequency of dicentric chromosomal aberrations in blood lymphocytes was used to estimate doses in a simulated criticality accident. The simulation consisted of three exposures; approximately 5 Gy with a bare source and 1 and 2 Gy with a lead-shielded source. Three laboratories made separate estimates of the doses. These were made by the iterative method of apportioning the observed dicentric frequencies between the gamma and neutron components, taking account of a given gamma/neutron dose ratio, and referring the separated dicentric frequencies to dose-response calibration curves. An alternative method, based on Bayesian ideas, was employed. This was developed for interpreting dicentric frequencies in situations where the gamma/neutron ratio is uncertain. Both methods gave very similar results. One laboratory produced dose estimates close to the eventual exercise reference doses and the other laboratories estimated slightly higher values. The main reason for the higher values was the calibration relationships for fission neutrons.

  16. Exploratory analysis of Spanish energetic mining accidents.

    PubMed

    Sanmiquel, Lluís; Freijo, Modesto; Rossell, Josep M

    2012-01-01

    Using data on work accidents and annual mining statistics, the paper studies work-related accidents in the Spanish energetic mining sector in 1999-2008. The following 3 parameters are considered: age, experience and size of the mine (in number of workers) where the accident took place. The main objective of this paper is to show the relationship between different accident indicators: risk index (as an expression of the incidence), average duration index for the age and size of the mine variables (as a measure of the seriousness of an accident), and the gravity index for the various sizes of mines (which measures the seriousness of an accident, too). The conclusions of this study could be useful to develop suitable prevention policies that would contribute towards a decrease in work-related accidents in the Spanish energetic mining industry.

  17. TMI-2 accident: core heat-up analysis

    SciTech Connect

    Ardron, K.H.; Cain, D.G.

    1981-01-01

    This report summarizes NSAC study of reactor core thermal conditions during the accident at Three Mile Island, Unit 2. The study focuses primarily on the time period from core uncovery (approximately 113 minutes after turbine trip) through the initiation of sustained high pressure injection (after 202 minutes). The transient analysis is based upon established sequences of events; plant data; post-accident measurements; interpretation or indirect use of instrument responses to accident conditions.

  18. Development of Database for Accident Analysis in Indian Mines

    NASA Astrophysics Data System (ADS)

    Tripathy, Debi Prasad; Guru Raghavendra Reddy, K.

    2016-10-01

    Mining is a hazardous industry and high accident rates associated with underground mining is a cause of deep concern. Technological developments notwithstanding, rate of fatal accidents and reportable incidents have not shown corresponding levels of decline. This paper argues that adoption of appropriate safety standards by both mine management and the government may result in appreciable reduction in accident frequency. This can be achieved by using the technology in improving the working conditions, sensitising workers and managers about causes and prevention of accidents. Inputs required for a detailed analysis of an accident include information on location, time, type, cost of accident, victim, nature of injury, personal and environmental factors etc. Such information can be generated from data available in the standard coded accident report form. This paper presents a web based application for accident analysis in Indian mines during 2001-2013. An accident database (SafeStat) prototype based on Intranet of the TCP/IP agreement, as developed by the authors, is also discussed.

  19. NASA's Accident Precursor Analysis Process and the International Space Station

    NASA Technical Reports Server (NTRS)

    Groen, Frank; Lutomski, Michael

    2010-01-01

    This viewgraph presentation reviews the implementation of Accident Precursor Analysis (APA), as well as the evaluation of In-Flight Investigations (IFI) and Problem Reporting and Corrective Action (PRACA) data for the identification of unrecognized accident potentials on the International Space Station.

  20. [Severe parachuting accident. Analysis of 122 cases].

    PubMed

    Krauss, U; Mischkowsky, T

    1993-06-01

    Based on a population of 122 severely injured patients the causes of paragliding accidents and the patterns of injury are analyzed. A questionnaire is used to establish a sport-specific profile for the paragliding pilot. The lower limbs (55.7%) and the lower parts of the spine (45.9%) are the most frequently injured parts of the body. There is a high risk of multiple injuries after a single accident because of the tremendous axial power. The standard of equipment is good in over 90% of the cases. Insufficient training and failure to take account of geographical and meteorological conditions are the main determinants of accidents sustained by paragliders, most of whom are young. Nevertheless, 80% of our patients want to continue paragliding. Finally some advice is given on how to prevent paragliding accidents and injuries.

  1. An analysis of pileup accidents in highway systems

    NASA Astrophysics Data System (ADS)

    Chang, Jau-Yang; Lai, Wun-Cing

    2016-02-01

    Pileup accident is a multi-vehicle collision occurring in the lane and producing by successive following vehicles. It is a special collision on highway. The probability of the occurrence of pileup accident is lower than that of the other accidents in highway systems. However, the pileup accident leads to injuries and damages which are often serious. In this paper, we analyze the occurrence of pileup accidents by considering the three types of dangerous collisions in highway systems. We evaluate those corresponding to rear-end collision, lane-changing collision, and double lane-changing collision. We simulate four road driving strategies to investigate the relationships between different vehicle collisions and pileup accidents. In accordance with the simulation and analysis, it is shown that the double lane-changing collisions result in an increase of the occurrence of pileup accidents. Additionally, we found that the probability of the occurrence of pileup accidents can be reduced when the speeds of vehicles are suitably constrained in highway systems.

  2. Analysis of traffic accidents on rural highways using Latent Class Clustering and Bayesian Networks.

    PubMed

    de Oña, Juan; López, Griselda; Mujalli, Randa; Calvo, Francisco J

    2013-03-01

    One of the principal objectives of traffic accident analyses is to identify key factors that affect the severity of an accident. However, with the presence of heterogeneity in the raw data used, the analysis of traffic accidents becomes difficult. In this paper, Latent Class Cluster (LCC) is used as a preliminary tool for segmentation of 3229 accidents on rural highways in Granada (Spain) between 2005 and 2008. Next, Bayesian Networks (BNs) are used to identify the main factors involved in accident severity for both, the entire database (EDB) and the clusters previously obtained by LCC. The results of these cluster-based analyses are compared with the results of a full-data analysis. The results show that the combined use of both techniques is very interesting as it reveals further information that would not have been obtained without prior segmentation of the data. BN inference is used to obtain the variables that best identify accidents with killed or seriously injured. Accident type and sight distance have been identify in all the cases analysed; other variables such as time, occupant involved or age are identified in EDB and only in one cluster; whereas variables vehicles involved, number of injuries, atmospheric factors, pavement markings and pavement width are identified only in one cluster.

  3. The covariance between the number of accidents and the number of victims in multivariate analysis of accident related outcomes.

    PubMed

    Bijleveld, F D

    2005-07-01

    In this study some statistical issues involved in the simultaneous analysis of accident related outcomes of the road traffic process are investigated. Since accident related outcomes like the number of victims, fatalities or accidents show interdependencies, their simultaneous analysis requires that these interdependencies are taken into account. One particular interdependency is the number of fatal accidents that is always smaller than the number of fatalities as at least one fatality results from a fatal accident. More generally, when the number of accidents increases, the number of people injured as a result of these accidents will also increase. Since dependencies between accident related outcomes are reflected in the variance-covariance structure of the outcomes, the main focus of the present study is on establishing this structure. As this study shows it is possible to derive relatively simple expressions for estimates of the variances and covariances of (logarithms of) accidents and victim counts. One example reveals a substantial effect of the inclusion of covariance terms in the estimation of a confidence region of a mortality rate. The accuracy of the estimated variance-covariance structure of the accident related outcomes is evaluated using samples of real life accident data from The Netherlands. Additionally, the effect of small expected counts on the variance estimate of the logarithm of the counts is investigated.

  4. Case for integral core-disruptive accident analysis

    SciTech Connect

    Luck, L B; Bell, C R

    1985-01-01

    Integral analysis is an approach used at the Los Alamos National Laboratory to cope with the broad multiplicity of accident paths and complex phenomena that characterize the transition phase of core-disruptive accident progression in a liquid-metal-cooled fast breeder reactor. The approach is based on the combination of a reference calculation, which is intended to represent a band of similar accident paths, and associated system- and separate-effect studies, which are designed to determine the effect of uncertainties. Results are interpreted in the context of a probabilistic framework. The approach was applied successfully in two studies; illustrations from the Clinch River Breeder Reactor licensing assessment are included.

  5. Analysis of Credible Accidents for Argonaut Reactors

    SciTech Connect

    Hawley, S. C.; Kathern, R. L.; Robkin, M. A.

    1981-04-01

    Five areas of potential accidents have been evaluated for the Argonaut-UTR reactors. They are: • insertion of excess reactivity • catastrophic rearrangement of the core • explosive chemical reaction • graphite fire • fuel-handling accident. A nuclear excursion resulting from the rapid insertion of the maximum available excess reactivity would produce only 12 MWs which is insufficient to cause fuel melting even with conservative assumptions. Although precise structural rearrangement of the core would create a potential hazard, it is simply not credible to assume that such an arrangement would result from the forces of an earthquake or other catastrophic event. Even damage to the fuel from falling debris or other objects is unlikely given the normal reactor structure. An explosion from a metal-water reaction could not occur because there is no credible source of sufficient energy to initiate the reaction. A graphite fire could conceivably create some damage to the reactor but not enough to melt any fuel or initiate a metal-water reaction. The only credible accident involving offsite doses was determined to be a fuel-handling accident which, given highly conservative assumptions, would produce a whole-body dose equivalent of 2 rem from noble gas immersion and a lifetime dose equivalent commitment to the thyroid of 43 rem from radioiodines.

  6. Bus accident analysis of routes with/without bus priority.

    PubMed

    Goh, Kelvin Chun Keong; Currie, Graham; Sarvi, Majid; Logan, David

    2014-04-01

    This paper summarises findings on road safety performance and bus-involved accidents in Melbourne along roads where bus priority measures had been applied. Results from an empirical analysis of the accident types revealed significant reduction in the proportion of accidents involving buses hitting stationary objects and vehicles, which suggests the effect of bus priority in addressing manoeuvrability issues for buses. A mixed-effects negative binomial (MENB) regression and back-propagation neural network (BPNN) modelling of bus accidents considering wider influences on accident rates at a route section level also revealed significant safety benefits when bus priority is provided. Sensitivity analyses done on the BPNN model showed general agreement in the predicted accident frequency between both models. The slightly better performance recorded by the MENB model results suggests merits in adopting a mixed effects modelling approach for accident count prediction in practice given its capability to account for unobserved location and time-specific factors. A major implication of this research is that bus priority in Melbourne's context acts to improve road safety and should be a major consideration for road management agencies when implementing bus priority and road schemes.

  7. The effects on accidents of studded tires and laws banning their use: a meta-analysis of evaluation studies.

    PubMed

    Elvik, R

    1999-01-01

    Studies that have evaluated the effects on accidents of studded tires are reviewed. There are two types of evaluation studies with respect to the safety effects of studded tires: (1) Studies of the effect on automobile accident rates of using studded tires; and (2) studies of the effect on accidents of banning the use of studded tires. The results of studies of the effects of studded tires on automobile accident rates are found to vary substantially, depending on the quality of the study design. Recent studies employing multivariate techniques of analysis to control for confounding factors, attribute to studded tires minor declines in automobile accident rates of 5% for snow- or ice-covered roads, 2% for bare roads and 4% for all road surfaces combined. The results of these studies are consistent with the most recent estimates of the effect on accidents of banning studded tires. It is concluded that studded tires probably confer a slight safety benefit during wintertime.

  8. Analysis of tritium mission FMEF/FAA fuel handling accidents

    SciTech Connect

    Van Keuren, J.C.

    1997-11-18

    The Fuels Material Examination Facility/Fuel Assembly Area is proposed to be used for fabrication of mixed oxide fuel to support the Fast Flux Test Facility (FFTF) tritium/medical isotope mission. The plutonium isotope mix for the new mission is different than that analyzed in the FMEF safety analysis report. A reanalysis was performed of three representative accidents for the revised plutonium mix to determine the impact on the safety analysis. Current versions computer codes and meterology data files were used for the analysis. The revised accidents were a criticality, an explosion in a glovebox, and a tornado. The analysis concluded that risk guidelines were met with the revised plutonium mix.

  9. Historical analysis of US pipeline accidents triggered by natural hazards

    NASA Astrophysics Data System (ADS)

    Girgin, Serkan; Krausmann, Elisabeth

    2015-04-01

    Natural hazards, such as earthquakes, floods, landslides, or lightning, can initiate accidents in oil and gas pipelines with potentially major consequences on the population or the environment due to toxic releases, fires and explosions. Accidents of this type are also referred to as Natech events. Many major accidents highlight the risk associated with natural-hazard impact on pipelines transporting dangerous substances. For instance, in the USA in 1994, flooding of the San Jacinto River caused the rupture of 8 and the undermining of 29 pipelines by the floodwaters. About 5.5 million litres of petroleum and related products were spilled into the river and ignited. As a results, 547 people were injured and significant environmental damage occurred. Post-incident analysis is a valuable tool for better understanding the causes, dynamics and impacts of pipeline Natech accidents in support of future accident prevention and mitigation. Therefore, data on onshore hazardous-liquid pipeline accidents collected by the US Pipeline and Hazardous Materials Safety Administration (PHMSA) was analysed. For this purpose, a database-driven incident data analysis system was developed to aid the rapid review and categorization of PHMSA incident reports. Using an automated data-mining process followed by a peer review of the incident records and supported by natural hazard databases and external information sources, the pipeline Natechs were identified. As a by-product of the data-collection process, the database now includes over 800,000 incidents from all causes in industrial and transportation activities, which are automatically classified in the same way as the PHMSA record. This presentation describes the data collection and reviewing steps conducted during the study, provides information on the developed database and data analysis tools, and reports the findings of a statistical analysis of the identified hazardous liquid pipeline incidents in terms of accident dynamics and

  10. Analysis of FY79 Army Aircraft Accidents.

    DTIC Science & Technology

    1980-04-01

    materiel failure/ malfunction 1. A accident. taskerrr (E) s Jb prforanc whch evited The acronym for the 3W approach to the Investigation, fro tht rquied y... lulli , It t , 1AZ" l iil~ i ..-... lI :.].,;.’,, - ,- S !5U" i_ ’ , o ’o , "% ", . #.,""" ".’ - "-’.’’’’-. "" " "’ ."- " " " II I S.7 44’ * U 11 Imem <I

  11. Accident Sequence Evaluation Program: Human reliability analysis procedure

    SciTech Connect

    Swain, A.D.

    1987-02-01

    This document presents a shortened version of the procedure, models, and data for human reliability analysis (HRA) which are presented in the Handbook of Human Reliability Analysis With emphasis on Nuclear Power Plant Applications (NUREG/CR-1278, August 1983). This shortened version was prepared and tried out as part of the Accident Sequence Evaluation Program (ASEP) funded by the US Nuclear Regulatory Commission and managed by Sandia National Laboratories. The intent of this new HRA procedure, called the ''ASEP HRA Procedure,'' is to enable systems analysts, with minimal support from experts in human reliability analysis, to make estimates of human error probabilities and other human performance characteristics which are sufficiently accurate for many probabilistic risk assessments. The ASEP HRA Procedure consists of a Pre-Accident Screening HRA, a Pre-Accident Nominal HRA, a Post-Accident Screening HRA, and a Post-Accident Nominal HRA. The procedure in this document includes changes made after tryout and evaluation of the procedure in four nuclear power plants by four different systems analysts and related personnel, including human reliability specialists. The changes consist of some additional explanatory material (including examples), and more detailed definitions of some of the terms. 42 refs.

  12. Indonesian railway accidents--utilizing Human Factors Analysis and Classification System in determining potential contributing factors.

    PubMed

    Iridiastadi, Hardianto; Ikatrinasari, Zulfa Fitri

    2012-01-01

    The prevalence of Indonesian railway accidents has not been declining, with hundreds of fatalities reported in the past decade. As an effort to help the National Transportation Safety Committee (NTSC), this study was conducted that aimed at understanding factors that might have contributed to the accidents. Human Factors Analysis and Classification System (HFACS) was utilized for this purpose. A total of nine accident reports (provided by the Indonesian NTSC) involving fatalities were studied using the technique. Results of this study indicated 72 factors that were closely related to the accidents. Of these, roughly 22% were considered as operator acts while about 39% were related to preconditions for operator acts. Supervisory represented 14% of the factors, and the remaining (about 25%) were associated with organizational factors. It was concluded that, while train drivers indeed played an important role in the accidents, interventions solely directed toward train drivers may not be adequate. A more comprehensive approach in minimizing the accidents should be conducted that addresses all the four aspects of HFACS.

  13. Speciation analysis of I-127,129 in the crop field soil contaminated by the Fukushima Dai-ichi nuclear power plant accident with newly developed chemical separation techniques

    NASA Astrophysics Data System (ADS)

    Honda, Maki; Matsuzaki, Hiroyuki; Saito, Takumi; Nagai, Hisao

    2014-05-01

    In previous study, we investigated the depth profile of the accident derived I-129 and downward migration speed in soils of near-field of Fukushima Dai-ichi Nuclear Power Plant, including crop fields and man-made fields. I-129 in soil was measured by AMS and stable iodine (I-127) was measured by ICP-MS at MALT (Micro Analysis Laboratory, Tandem accelerator), The University of Tokyo. It was found that I-129 was concentrated near surface but distributed deeper compared with Cs-137. It was also found that I-129 seems to move downward more quickly than Cs-137. To investigate the adsorption mechanism and the elemental process of migration of the accident derived I-129 in soil, it is important to know what kind of component the I-129 combines with. Recent studies on the X-ray absorption fine structure (XAFS), especially near edge structure (XANES), reported that the stable iodine (I-127) in soil existed as an organic component. However, it had not yet been proved that it was also the case with the accident derived I-129 because it had been incorporated in the soil system only recently and the abundance of I-129 in soil was more than 8 orders of magnitude smaller than sub-ppm level stable iodine (I-127). In this study a progressive sequential extraction method including the dialysis and the dynamic headspace method was newly developed to obtain only the iodine sticking to the soil organic component. The stable iodine can be quantified by direct analysis of the fraction and I-129 can be quantified by AMS method of the fraction added with carrier. The fraction of the organic component for I-127 and I-129 can be evaluated respectively by comparing with the other fraction and/or with the total concentration obtained by the bulk analysis (e.g. by the pyrohydrolysis).

  14. Shipping container response to severe highway and railway accident conditions: Appendices

    SciTech Connect

    Fischer, L.E.; Chou, C.K.; Gerhard, M.A.; Kimura, C.Y.; Martin, R.W.; Mensing, R.W.; Mount, M.E.; Witte, M.C.

    1987-02-01

    Volume 2 contains the following appendices: Severe accident data; truck accident data; railroad accident data; highway survey data and bridge column properties; structural analysis; thermal analysis; probability estimation techniques; and benchmarking for computer codes used in impact analysis. (LN)

  15. MELCOR accident analysis for ARIES-ACT

    SciTech Connect

    Paul W. Humrickhouse; Brad J. Merrill

    2012-08-01

    We model a loss of flow accident (LOFA) in the ARIES-ACT1 tokamak design. ARIES-ACT1 features an advanced SiC blanket with LiPb as coolant and breeder, a helium cooled steel structural ring and tungsten divertors, a thin-walled, helium cooled vacuum vessel, and a room temperature water-cooled shield outside the vacuum vessel. The water heat transfer system is designed to remove heat by natural circulation during a LOFA. The MELCOR model uses time-dependent decay heats for each component determined by 1-D modeling. The MELCOR model shows that, despite periodic boiling of the water coolant, that structures are kept adequately cool by the passive safety system.

  16. Accident analysis of the windowless target system

    SciTech Connect

    Bianchi, F.; Ferri, R.

    2006-07-01

    Transmutation systems are able to reduce the radio-toxicity and amount of High-Level Wastes (HLW), which are the main concerns related to the peaceful use of nuclear energy, and therefore they should make nuclear energy more easily acceptable by population. A transmutation system consists of a sub-critical fast reactor, an accelerator and a Target System, where the spallation reactions needed to sustain the chain reaction take place. Three options were proposed for the Target System within the European project PDS-XADS (Preliminary Design Studies on an Experimental Accelerator Driven System): window, windowless and solid. This paper describes the constraints taken into account in the design of the windowless Target System for the large Lead-Bismuth-Eutectic cooled XADS and deals with the results of the calculations performed to assess the behaviour of the target during some accident sequences related to pump trips. (authors)

  17. Analysis of the temporal properties in car accident time series

    NASA Astrophysics Data System (ADS)

    Telesca, Luciano; Lovallo, Michele

    2008-05-01

    In this paper we study the time-clustering behavior of sequences of car accidents, using data from a freely available database in the internet. The Allan Factor analysis, which is a well-suited method to investigate time-dynamical behaviors in point processes, has revealed that the car accident sequences are characterized by a general time-scaling behavior, with the presence of cyclic components. These results indicate that the time dynamics of the events are not Poissonian but long range correlated with periodicities ranging from 12 h to 1 year.

  18. Synthesis of quantitative and qualitative evidence for accident analysis in risk-based highway planning.

    PubMed

    Lambert, James H; Peterson, Kenneth D; Joshi, Nilesh N

    2006-09-01

    Accident analysis involves the use of both quantitative and qualitative data in decision-making. The aim of this paper is to demonstrate the synthesis of relevant quantitative and qualitative evidence for accident analysis and for planning a large and diverse portfolio of highway investment projects. The proposed analysis and visualization techniques along with traditional mathematical modeling serve as an aid to planners, engineers, and the public in comparing the benefits of current and proposed improvement projects. The analysis uses data on crash rates, average daily traffic, cost estimates from highway agency databases, and project portfolios for regions and localities. It also utilizes up to two motivations out of seven that are outlined in the Transportation Equity Act for the 21st Century (TEA-21). Three case studies demonstrate the risk-based approach to accident analysis for short- and long-range transportation plans. The approach is adaptable to other topics in accident analysis and prevention that involve the use of quantitative and qualitative evidence, risk analysis, and multi-criteria decision-making for project portfolio selection.

  19. Final safety analysis report for the Galileo Mission: Volume 2, Book 2: Accident model document: Appendices

    SciTech Connect

    Not Available

    1988-12-15

    This section of the Accident Model Document (AMD) presents the appendices which describe the various analyses that have been conducted for use in the Galileo Final Safety Analysis Report II, Volume II. Included in these appendices are the approaches, techniques, conditions and assumptions used in the development of the analytical models plus the detailed results of the analyses. Also included in these appendices are summaries of the accidents and their associated probabilities and environment models taken from the Shuttle Data Book (NSTS-08116), plus summaries of the several segments of the recent GPHS safety test program. The information presented in these appendices is used in Section 3.0 of the AMD to develop the Failure/Abort Sequence Trees (FASTs) and to determine the fuel releases (source terms) resulting from the potential Space Shuttle/IUS accidents throughout the missions.

  20. Upgrading the safety toolkit: Initiatives of the accident analysis subgroup

    SciTech Connect

    O'Kula, K.R.; Chung, D.Y.

    1999-07-01

    Since its inception, the Accident Analysis Subgroup (AAS) of the Energy Facility Contractors Group (EFCOG) has been a leading organization promoting development and application of appropriate methodologies for safety analysis of US Department of Energy (DOE) installations. The AAS, one of seven chartered by the EFCOG Safety Analysis Working Group, has performed an oversight function and provided direction to several technical groups. These efforts have been instrumental toward formal evaluation of computer models, improving the pedigree on high-use computer models, and development of the user-friendly Accident Analysis Guidebook (AAG). All of these improvements have improved the analytical toolkit for best complying with DOE orders and standards shaping safety analysis reports (SARs) and related documentation. Major support for these objectives has been through DOE/DP-45.

  1. Analysis of Crew Fatigue in AIA Guantanamo Bay Aviation Accident

    NASA Technical Reports Server (NTRS)

    Rosekind, Mark R.; Gregory, Kevin B.; Miller, Donna L.; Co, Elizabeth L.; Lebacqz, J. Victor; Statler, Irving C. (Technical Monitor)

    1994-01-01

    Flight operations can engender fatigue, which can affect flight crew performance, vigilance, and mood. The National Transportation Safety Board (NTSB) requested the NASA Fatigue Countermeasures Program to analyze crew fatigue factors in an aviation accident that occurred at Guantanamo Bay, Cuba. There are specific fatigue factors that can be considered in such investigations: cumulative sleep loss, continuous hours of wakefulness prior to the incident or accident, and the time of day at which the accident occurred. Data from the NTSB Human Performance Investigator's Factual Report, the Operations Group Chairman's Factual Report, and the Flight 808 Crew Statements were analyzed, using conservative estimates and averages to reconcile discrepancies among the sources. Analysis of these data determined the following: the entire crew displayed cumulative sleep loss, operated during an extended period of continuous wakefulness, and obtained sleep at times in opposition to the circadian disposition for sleep, and that the accident occurred in the afternoon window of physiological sleepiness. In addition to these findings, evidence that fatigue affected performance was suggested by the cockpit voice recorder (CVR) transcript as well as in the captain's testimony. Examples from the CVR showed degraded decision-making skills, fixation, and slowed responses, all of which can be affected by fatigue; also, the captain testified to feeling "lethargic and indifferent" just prior to the accident. Therefore, the sleep/wake history data supports the hypothesis that fatigue was a factor that affected crewmembers' performance. Furthermore, the examples from the CVR and the captain's testimony support the hypothesis that the fatigue had an impact on specific actions involved in the occurrence of the accident.

  2. Data analysis techniques

    NASA Technical Reports Server (NTRS)

    Park, Steve

    1990-01-01

    A large and diverse number of computational techniques are routinely used to process and analyze remotely sensed data. These techniques include: univariate statistics; multivariate statistics; principal component analysis; pattern recognition and classification; other multivariate techniques; geometric correction; registration and resampling; radiometric correction; enhancement; restoration; Fourier analysis; and filtering. Each of these techniques will be considered, in order.

  3. INDUSTRIAL/MILITARY ACTIVITY-INITIATED ACCIDENT SCREENING ANALYSIS

    SciTech Connect

    D.A. Kalinich

    1999-09-27

    Impacts due to nearby installations and operations were determined in the Preliminary MGDS Hazards Analysis (CRWMS M&O 1996) to be potentially applicable to the proposed repository at Yucca Mountain. This determination was conservatively based on limited knowledge of the potential activities ongoing on or off the Nevada Test Site (NTS). It is intended that the Industrial/Military Activity-Initiated Accident Screening Analysis provided herein will meet the requirements of the ''Standard Review Plan for the Review of Safety Analysis Reports for Nuclear Power Plants'' (NRC 1987) in establishing whether this external event can be screened from further consideration or must be included as a design basis event (DBE) in the development of accident scenarios for the Monitored Geologic Repository (MGR). This analysis only considers issues related to preclosure radiological safety. Issues important to waste isolation as related to impact from nearby installations will be covered in the MGR performance assessment.

  4. Cold Vacuum Drying facility design basis accident analysis documentation

    SciTech Connect

    CROWE, R.D.

    2000-08-08

    This document provides the detailed accident analysis to support HNF-3553, Annex B, Spent Nuclear Fuel Project Final Safety Analysis Report (FSAR), ''Cold Vacuum Drying Facility Final Safety Analysis Report.'' All assumptions, parameters, and models used to provide the analysis of the design basis accidents are documented to support the conclusions in the FSAR. The calculations in this document address the design basis accidents (DBAs) selected for analysis in HNF-3553, ''Spent Nuclear Fuel Project Final Safety Analysis Report'', Annex B, ''Cold Vacuum Drying Facility Final Safety Analysis Report.'' The objective is to determine the quantity of radioactive particulate available for release at any point during processing at the Cold Vacuum Drying Facility (CVDF) and to use that quantity to determine the amount of radioactive material released during the DBAs. The radioactive material released is used to determine dose consequences to receptors at four locations, and the dose consequences are compared with the appropriate evaluation guidelines and release limits to ascertain the need for preventive and mitigative controls.

  5. Analysis of dental materials as an aid to identification in aircraft accidents.

    PubMed

    Wilson, G S; Cruickshanks-Boyd, D W

    1982-04-01

    The failure to achieve positive identification of aircrew following an aircraft accident need not prevent a full autopsy and toxicological examination to ascertain possible medical factors involved in the accident. Energy-dispersive electron microprobe analysis provides morphological, qualitative, and accurate quantitative analysis of the composition of dental amalgam. Wet chemical analysis can be used to determine the elemental composition of crowns, bridges and partial dentures. Unfilled resin can be analyzed by infrared spectroscopy. Detailed analysis of filled composite restorative resins has not yet been achieved in the "as-set" condition to permit discrimination between manufacturers' products. Future work will involve filler studies and pyrolysis of the composite resins by thermogravimetric analysis to determine percentage weight loss when the sample examined is subjected to a controlled heating regime. With these available techniques, corroborative evidence achieved from the scientific study of materials can augment standard forensic dental results to obtain a positive identification.

  6. Analysis of dental materials as an aid to identification in aircraft accidents

    SciTech Connect

    Wilson, G.S.; Cruickshanks-Boyd, D.W.

    1982-04-01

    The failure to achieve positive identification of aircrew following an aircraft accident need not prevent a full autopsy and toxicological examination to ascertain possible medical factors involved in the accident. Energy-dispersive electron microprobe analysis provides morphological, qualitative, and accurate quantitative analysis of the composition of dental amalgam. Wet chemical analysis can be used to determine the elemental composition of crowns, bridges and partial dentures. Unfilled resin can be analyzed by infrared spectroscopy. Detailed analysis of filled composite restorative resins has not yet been achieved in the as-set condition to permit discrimination between manufacturers' products. Future work will involve filler studies and pyrolysis of the composite resins by thermogravimetric analysis to determine percentage weight loss when the sample examined is subjected to a controlled heating regime. With these available techniques, corroborative evidence achieved from the scientific study of materials can augment standard forensic dental results to obtain a positive identification.

  7. Impact of traffic congestion on road accidents: a spatial analysis of the M25 motorway in England.

    PubMed

    Wang, Chao; Quddus, Mohammed A; Ison, Stephen G

    2009-07-01

    Traffic congestion and road accidents are two external costs of transport and the reduction of their impacts is often one of the primary objectives for transport policy makers. The relationship between traffic congestion and road accidents however is not apparent and less studied. It is speculated that there may be an inverse relationship between traffic congestion and road accidents, and as such this poses a potential dilemma for transport policy makers. This study aims to explore the impact of traffic congestion on the frequency of road accidents using a spatial analysis approach, while controlling for other relevant factors that may affect road accidents. The M25 London orbital motorway, divided into 70 segments, was chosen to conduct this study and relevant data on road accidents, traffic and road characteristics were collected. A robust technique has been developed to map M25 accidents onto its segments. Since existing studies have often used a proxy to measure the level of congestion, this study has employed a precise congestion measurement. A series of Poisson based non-spatial (such as Poisson-lognormal and Poisson-gamma) and spatial (Poisson-lognormal with conditional autoregressive priors) models have been used to account for the effects of both heterogeneity and spatial correlation. The results suggest that traffic congestion has little or no impact on the frequency of road accidents on the M25 motorway. All other relevant factors have provided results consistent with existing studies.

  8. Systems thinking, the Swiss Cheese Model and accident analysis: a comparative systemic analysis of the Grayrigg train derailment using the ATSB, AcciMap and STAMP models.

    PubMed

    Underwood, Peter; Waterson, Patrick

    2014-07-01

    The Swiss Cheese Model (SCM) is the most popular accident causation model and is widely used throughout various industries. A debate exists in the research literature over whether the SCM remains a viable tool for accident analysis. Critics of the model suggest that it provides a sequential, oversimplified view of accidents. Conversely, proponents suggest that it embodies the concepts of systems theory, as per the contemporary systemic analysis techniques. The aim of this paper was to consider whether the SCM can provide a systems thinking approach and remain a viable option for accident analysis. To achieve this, the train derailment at Grayrigg was analysed with an SCM-based model (the ATSB accident investigation model) and two systemic accident analysis methods (AcciMap and STAMP). The analysis outputs and usage of the techniques were compared. The findings of the study showed that each model applied the systems thinking approach. However, the ATSB model and AcciMap graphically presented their findings in a more succinct manner, whereas STAMP more clearly embodied the concepts of systems theory. The study suggests that, whilst the selection of an analysis method is subject to trade-offs that practitioners and researchers must make, the SCM remains a viable model for accident analysis.

  9. Accident analysis of heavy water cooled thorium breeder reactor

    SciTech Connect

    Yulianti, Yanti; Su’ud, Zaki; Takaki, Naoyuki

    2015-04-16

    power reactor has a peak value before reactor has new balance condition. The analysis showed that temperatures of fuel and claddings during accident are still below limitations which are in secure condition.

  10. Road Traffic Accident Analysis of Ajmer City Using Remote Sensing and GIS Technology

    NASA Astrophysics Data System (ADS)

    Bhalla, P.; Tripathi, S.; Palria, S.

    2014-12-01

    With advancement in technology, new and sophisticated models of vehicle are available and their numbers are increasing day by day. A traffic accident has multi-facet characteristics associated with it. In India 93% of crashes occur due to Human induced factor (wholly or partly). For proper traffic accident analysis use of GIS technology has become an inevitable tool. The traditional accident database is a summary spreadsheet format using codes and mileposts to denote location, type and severity of accidents. Geo-referenced accident database is location-referenced. It incorporates a GIS graphical interface with the accident information to allow for query searches on various accident attributes. Ajmer city, headquarter of Ajmer district, Rajasthan has been selected as the study area. According to Police records, 1531 accidents occur during 2009-2013. Maximum accident occurs in 2009 and the maximum death in 2013. Cars, jeeps, auto, pickup and tempo are mostly responsible for accidents and that the occurrence of accidents is mostly concentrated between 4PM to 10PM. GIS has proved to be a good tool for analyzing multifaceted nature of accidents. While road safety is a critical issue, yet it is handled in an adhoc manner. This Study is a demonstration of application of GIS for developing an efficient database on road accidents taking Ajmer City as a study. If such type of database is developed for other cities, a proper analysis of accidents can be undertaken and suitable management strategies for traffic regulation can be successfully proposed.

  11. A systemic analysis of South Korea Sewol ferry accident - Striking a balance between learning and accountability.

    PubMed

    Kee, Dohyung; Jun, Gyuchan Thomas; Waterson, Patrick; Haslam, Roger

    2017-03-01

    The South Korea Sewol ferry accident in April 2014 claimed the lives of over 300 passengers and led to criminal charges of 399 personnel concerned including imprisonment of 154 of them as of Oct 2014. Blame and punishment culture can be prevalent in a more hierarchical society like South Korea as shown in the aftermath of this disaster. This study aims to analyse the South Korea ferry accident using Rasmussen's risk management framework and the associated AcciMap technique and to propose recommendations drawn from an AcciMap-based focus group with systems safety experts. The data for the accident analysis were collected mainly from an interim investigation report by the Board of Audit and Inspection of Korea and major South Korean and foreign newspapers. The analysis showed that the accident was attributed to many contributing factors arising from front-line operators, management, regulators and government. It also showed how the multiple factors including economic, social and political pressures and individual workload contributed to the accident and how they affected each other. This AcciMap was presented to 27 safety researchers and experts at 'the legacy of Jens Rasmussen' symposium adjunct to ODAM2014. Their recommendations were captured through a focus group. The four main recommendations include forgive (no blame and punishment on individuals), analyse (socio-technical system-based), learn (from why things do not go wrong) and change (bottom-up safety culture and safety system management). The findings offer important insights into how this type of accident should be understood, analysed and the subsequent response.

  12. Luminescence techniques for dose reconstruction in accident situations: possibilites, limitations and uncertainties

    SciTech Connect

    Haskell, E.H.

    1996-12-31

    In a nuclear accident of even moderate size, locations will inevitably be exposed which do not have adequate monitoring. In these situations nontraditional dosimeters such as brick, tiles or other environmental materials have historically provided measurements against which models of transport and exposure could be tested. Given sufficient speed and accuracy, the utility of TL techniques applied to natural materials can extend well beyond model verification to a variety of dosimetric applications.

  13. Civil helicopter wire strike assessment study. Volume 2: Accident analysis briefs

    NASA Technical Reports Server (NTRS)

    Tuomela, C. H.; Brennan, M. F.

    1980-01-01

    A description and analysis of each of the 208 civil helicopter wire strike accidents reported to the National Transportation Safety Board (NTSB) for the ten year period 1970-1979 is given. The accident analysis briefs were based on pilot reports, FAA investigation reports, and such accident photographs as were made available. Briefs were grouped by year and, within year, by NTSB accident report number.

  14. NASA Accident Precursor Analysis Handbook, Version 1.0

    NASA Technical Reports Server (NTRS)

    Groen, Frank; Everett, Chris; Hall, Anthony; Insley, Scott

    2011-01-01

    Catastrophic accidents are usually preceded by precursory events that, although observable, are not recognized as harbingers of a tragedy until after the fact. In the nuclear industry, the Three Mile Island accident was preceded by at least two events portending the potential for severe consequences from an underappreciated causal mechanism. Anomalies whose failure mechanisms were integral to the losses of Space Transportation Systems (STS) Challenger and Columbia had been occurring within the STS fleet prior to those accidents. Both the Rogers Commission Report and the Columbia Accident Investigation Board report found that processes in place at the time did not respond to the prior anomalies in a way that shed light on their true risk implications. This includes the concern that, in the words of the NASA Aerospace Safety Advisory Panel (ASAP), "no process addresses the need to update a hazard analysis when anomalies occur" At a broader level, the ASAP noted in 2007 that NASA "could better gauge the likelihood of losses by developing leading indicators, rather than continue to depend on lagging indicators". These observations suggest a need to revalidate prior assumptions and conclusions of existing safety (and reliability) analyses, as well as to consider the potential for previously unrecognized accident scenarios, when unexpected or otherwise undesired behaviors of the system are observed. This need is also discussed in NASA's system safety handbook, which advocates a view of safety assurance as driving a program to take steps that are necessary to establish and maintain a valid and credible argument for the safety of its missions. It is the premise of this handbook that making cases for safety more experience-based allows NASA to be better informed about the safety performance of its systems, and will ultimately help it to manage safety in a more effective manner. The APA process described in this handbook provides a systematic means of analyzing candidate

  15. Accident patterns for construction-related workers: a cluster analysis

    NASA Astrophysics Data System (ADS)

    Liao, Chia-Wen; Tyan, Yaw-Yauan

    2011-12-01

    The construction industry has been identified as one of the most hazardous industries. The risk of constructionrelated workers is far greater than that in a manufacturing based industry. However, some steps can be taken to reduce worker risk through effective injury prevention strategies. In this article, k-means clustering methodology is employed in specifying the factors related to different worker types and in identifying the patterns of industrial occupational accidents. Accident reports during the period 1998 to 2008 are extracted from case reports of the Northern Region Inspection Office of the Council of Labor Affairs of Taiwan. The results show that the cluster analysis can indicate some patterns of occupational injuries in the construction industry. Inspection plans should be proposed according to the type of construction-related workers. The findings provide a direction for more effective inspection strategies and injury prevention programs.

  16. Accident patterns for construction-related workers: a cluster analysis

    NASA Astrophysics Data System (ADS)

    Liao, Chia-Wen; Tyan, Yaw-Yauan

    2012-01-01

    The construction industry has been identified as one of the most hazardous industries. The risk of constructionrelated workers is far greater than that in a manufacturing based industry. However, some steps can be taken to reduce worker risk through effective injury prevention strategies. In this article, k-means clustering methodology is employed in specifying the factors related to different worker types and in identifying the patterns of industrial occupational accidents. Accident reports during the period 1998 to 2008 are extracted from case reports of the Northern Region Inspection Office of the Council of Labor Affairs of Taiwan. The results show that the cluster analysis can indicate some patterns of occupational injuries in the construction industry. Inspection plans should be proposed according to the type of construction-related workers. The findings provide a direction for more effective inspection strategies and injury prevention programs.

  17. Comprehensive Analysis of Two Downburst-Related Aircraft Accidents

    NASA Technical Reports Server (NTRS)

    Shen, J.; Parks, E. K.; Bach, R. E.

    1996-01-01

    Although downbursts have been identified as the major cause of a number of aircraft takeoff and landing accidents, only the 1985 Dallas/Fort Worth (DFW) and the more recent (July 1994) Charlotte, North Carolina, landing accidents provided sufficient onboard recorded data to perform a comprehensive analysis of the downburst phenomenon. The first step in the present analysis was the determination of the downburst wind components. Once the wind components and their gradients were determined, the degrading effect of the wind environment on the airplane's performance was calculated. This wind-shear-induced aircraft performance degradation, sometimes called the F-factor, was broken down into two components F(sub 1) and F(sub 2), representing the effect of the horizontal wind gradient and the vertical wind velocity, respectively. In both the DFW and Charlotte cases, F(sub 1) was found to be the dominant causal factor of the accident. Next, the aircraft in the two cases were mathematically modeled using the longitudinal equations of motion and the appropriate aerodynamic parameters. Based on the aircraft model and the determined winds, the aircraft response to the recorded pilot inputs showed good agreement with the onboard recordings. Finally, various landing abort strategies were studied. It was concluded that the most acceptable landing abort strategy from both an analytical and pilot's standpoint was to hold constant nose-up pitch attitude while operating at maximum engine thrust.

  18. Enhanced Accident Tolerant Fuels for LWRS - A Preliminary Systems Analysis

    SciTech Connect

    Gilles Youinou; R. Sonat Sen

    2013-09-01

    The severe accident at Fukushima Daiichi nuclear plants illustrates the need for continuous improvements through developing and implementing technologies that contribute to safe, reliable and cost-effective operation of the nuclear fleet. Development of enhanced accident tolerant fuel contributes to this effort. These fuels, in comparison with the standard zircaloy – UO2 system currently used by the LWR industry, should be designed such that they tolerate loss of active cooling in the core for a longer time period (depending on the LWR system and accident scenario) while maintaining or improving the fuel performance during normal operations, operational transients, and design-basis events. This report presents a preliminary systems analysis related to most of these concepts. The potential impacts of these innovative LWR fuels on the front-end of the fuel cycle, on the reactor operation and on the back-end of the fuel cycle are succinctly described without having the pretension of being exhaustive. Since the design of these various concepts is still a work in progress, this analysis can only be preliminary and could be updated as the designs converge on their respective final version.

  19. Uncertainty and sensitivity analysis of food pathway results with the MACCS Reactor Accident Consequence Model

    SciTech Connect

    Helton, J.C.; Johnson, J.D.; Rollstin, J.A.; Shiver, A.W.; Sprung, J.L.

    1995-01-01

    Uncertainty and sensitivity analysis techniques based on Latin hypercube sampling, partial correlation analysis and stepwise regression analysis are used in an investigation with the MACCS model of the food pathways associated with a severe accident at a nuclear power station. The primary purpose of this study is to provide guidance on the variables to be considered in future review work to reduce the uncertainty in the important variables used in the calculation of reactor accident consequences. The effects of 87 imprecisely-known input variables on the following reactor accident consequences are studied: crop growing season dose, crop long-term dose, milk growing season dose, total food pathways dose, total ingestion pathways dose, total long-term pathways dose, area dependent cost, crop disposal cost, milk disposal cost, condemnation area, crop disposal area and milk disposal area. When the predicted variables are considered collectively, the following input variables were found to be the dominant contributors to uncertainty: fraction of cesium deposition on grain fields that is retained on plant surfaces and transferred directly to grain, maximum allowable ground concentrations of Cs-137 and Sr-90 for production of crops, ground concentrations of Cs-134, Cs-137 and I-131 at which the disposal of milk will be initiated due to accidents that occur during the growing season, ground concentrations of Cs-134, I-131 and Sr-90 at which the disposal of crops will be initiated due to accidents that occur during the growing season, rate of depletion of Cs-137 and Sr-90 from the root zone, transfer of Sr-90 from soil to legumes, transfer of Cs-137 from soil to pasture, transfer of cesium from animal feed to meat, and the transfer of cesium, iodine and strontium from animal feed to milk.

  20. Analysis of Three Mile Island-Unit 2 accident

    SciTech Connect

    Not Available

    1980-03-01

    The Nuclear Safety Analysis Center (NSAC) of the Electric Power Research Institute has analyzed the Three Mile Island-2 accident. Early results of this analysis were a brief narrative summary, issued in mid-May 1979 and an initial version of this report issued later in 1979 as noted in the Foreword. The present report is a revised version of the 1979 report, containing summaries, a highly detailed sequence of events, a comparison of that sequence of events with those from other sources, 25 appendices, references and a list of abbreviations and acronyms. A matrix of equipment and system actions is included as a folded insert.

  1. A review of risk analysis and helicopter air ambulance accidents.

    PubMed

    Nix, Sam; Buckner, Steven; Cercone, Richard

    2014-01-01

    The Federal Aviation Administration announced a final rule in February 2014 that includes a requirement for helicopter air ambulance operators to institute preflight risk analysis programs. This qualitative study examined risk factors that were described in 22 preliminary, factual, and probable cause helicopter air ambulance accident and incident reports that were initiated by the National Transportation Safety Board between January 1, 2011, and December 31, 2013. Insights into the effectiveness of existing preflight risk analysis strategies were gained by comparing these risk factors with the preflight risk analysis guidance that is published by the Federal Aviation Administration in the Flight Standards Information Management System. When appropriate, a deeper understanding of the human factors that may have contributed to occurrences was gained through methodologies that are described in the Human Factors Analysis and Classification System. The results of this study suggest that there are some vulnerabilities in existing preflight risk analysis guidelines that may affect safety in the helicopter air ambulance industry. The likelihood that human factors contributed to most of the helicopter air ambulance accidents and incidents that occurred during the study period was also evidenced. The results of this study suggest that effective risk analysis programs should provide pilots with both preflight and in-flight resources.

  2. A flammability and combustion model for integrated accident analysis. [Advanced light water reactors

    SciTech Connect

    Plys, M.G.; Astleford, R.D.; Epstein, M. )

    1988-01-01

    A model for flammability characteristics and combustion of hydrogen and carbon monoxide mixtures is presented for application to severe accident analysis of Advanced Light Water Reactors (ALWR's). Flammability of general mixtures for thermodynamic conditions anticipated during a severe accident is quantified with a new correlation technique applied to data for several fuel and inertant mixtures and using accepted methods for combining these data. Combustion behavior is quantified by a mechanistic model consisting of a continuity and momentum balance for the burned gases, and considering an uncertainty parameter to match the idealized process to experiment. Benchmarks against experiment demonstrate the validity of this approach for a single recommended value of the flame flux multiplier parameter. The models presented here are equally applicable to analysis of current LWR's. 21 refs., 16 figs., 6 tabs.

  3. Application of Electron Microscopy Techniques to the Investigation of Space Shuttle Columbia Accident

    NASA Technical Reports Server (NTRS)

    Shah, Sandeep

    2005-01-01

    This viewgraph presentation gives an overview of the investigation into the breakup of the Space Shuttle Columbia, and addresses the importance of a failure analysis strategy for the investigation of the Columbia accident. The main focus of the presentation is on the usefulness of electron microscopy for analyzing slag deposits from the tiles and reinforced carbon-carbon (RCC) wing panels of the Columbia orbiter.

  4. Traffic accident analysis using GIS: a case study of Kyrenia City

    NASA Astrophysics Data System (ADS)

    Kara, Can; Akçit, Nuhcan

    2015-06-01

    Traffic accidents are causing major deaths in urban environments, so analyzing locations of the traffic accidents and their reasons is crucial. In this manner, patterns of accidents and hotspot distribution are analyzed by using geographic information technology. Locations of the traffic accidents in the years 2011, 2012 and 2013 are combined to generate the kernel distribution map of Kyrenia City. This analysis aims to find high dense intersections and segments within the city. Additionally, spatial autocorrelation methods Local Morans I and Getis-Ord Gi are employed . The results are discussed in detail for further analysis. Finally, required changes for numerous intersections are suggested to decrease potential risks of high dense accident locations.

  5. A variational technique for smoothing flight-test and accident data

    NASA Technical Reports Server (NTRS)

    Bach, R. E., Jr.

    1980-01-01

    The problem of determining aircraft motions along a trajectory is solved using a variational algorithm that generates unmeasured states and forcing functions, and estimates instrument bias and scale-factor errors. The problem is formulated as a nonlinear fixed-interval smoothing problem, and is solved as a sequence of linear two-point boundary value problems, using a sweep method. The algorithm has been implemented for use in flight-test and accident analysis. Aircraft motions are assumed to be governed by a six-degree-of-freedom kinematic model; forcing functions consist of body accelerations and winds, and the measurement model includes aerodynamic and radar data. Examples of the determination of aircraft motions from typical flight-test and accident data are presented.

  6. Predicting System Accidents with Model Analysis During Hybrid Simulation

    NASA Technical Reports Server (NTRS)

    Malin, Jane T.; Fleming, Land D.; Throop, David R.

    2002-01-01

    Standard discrete event simulation is commonly used to identify system bottlenecks and starving and blocking conditions in resources and services. The CONFIG hybrid discrete/continuous simulation tool can simulate such conditions in combination with inputs external to the simulation. This provides a means for evaluating the vulnerability to system accidents of a system's design, operating procedures, and control software. System accidents are brought about by complex unexpected interactions among multiple system failures , faulty or misleading sensor data, and inappropriate responses of human operators or software. The flows of resource and product materials play a central role in the hazardous situations that may arise in fluid transport and processing systems. We describe the capabilities of CONFIG for simulation-time linear circuit analysis of fluid flows in the context of model-based hazard analysis. We focus on how CONFIG simulates the static stresses in systems of flow. Unlike other flow-related properties, static stresses (or static potentials) cannot be represented by a set of state equations. The distribution of static stresses is dependent on the specific history of operations performed on a system. We discuss the use of this type of information in hazard analysis of system designs.

  7. Extension of ship accident analysis to multiple-package shipments

    SciTech Connect

    Mills, G.S.; Neuhauser, K.S.

    1997-11-01

    Severe ship accidents and the probability of radioactive material release from spent reactor fuel casks were investigated previously. Other forms of RAM, e.g., plutonium oxide powder, may be shipped in large numbers of packagings rather than in one to a few casks. These smaller, more numerous packagings are typically placed in ISO containers for ease of handling, and several ISO containers may be placed in one of several holds of a cargo ship. In such cases, the size of a radioactive release resulting from a severe collision with another ship is determined not by the likelihood of compromising a single, robust package but by the probability that a certain fraction of 10`s or 100`s of individual packagings is compromised. The previous analysis involved a statistical estimation of the frequency of accidents which would result in damage to a cask located in one of seven cargo holds in a collision with another ship. The results were obtained in the form of probabilities (frequencies) of accidents of increasing severity and of release fractions for each level of severity. This paper describes an extension of the same general method in which the multiple packages are assumed to be compacted by an intruding ship`s bow until there is no free space in the hold. At such a point, the remaining energy of the colliding ship is assumed to be dissipated by progressively crushing the RAM packagings and the probability of a particular fraction of package failures is estimated by adaptation of the statistical method used previously. The parameters of a common, well characterized packaging, the 6M with 2R inner containment vessel, were employed as an illustrative example of this analysis method. However, the method is readily applicable to other packagings for which crush strengths have been measured or can be estimated with satisfactory confidence.

  8. Speech analysis as an index of alcohol intoxication--the Exxon Valdez accident.

    PubMed

    Brenner, M; Cash, J R

    1991-09-01

    As part of its investigation of the EXXON VALDEZ tankship accident and oil spill, the National Transportation Safety Board (NTSB) examined the master's speech for alcohol-related effects. Recorded speech samples were obtained from marine radio communications tapes. The samples were tested for four effects associated with alcohol consumption is available scientific literature: slowed speech, speech errors, misarticulation of difficult sounds ("slurring"), and audible changes in speech quality. It was found that speech immediately before and after the accident displayed large changes of the sort associated with alcohol consumption. These changes were not readily explained by fatigue, psychological stress, drug effects, or medical problems. Speech analysis appears to be a useful technique to provide secondary evidence of alcohol impairment.

  9. Uncertainty and sensitivity analysis of early exposure results with the MACCS Reactor Accident Consequence Model

    SciTech Connect

    Helton, J.C.; Johnson, J.D.; McKay, M.D.; Shiver, A.W.; Sprung, J.L.

    1995-01-01

    Uncertainty and sensitivity analysis techniques based on Latin hypercube sampling, partial correlation analysis and stepwise regression analysis are used in an investigation with the MACCS model of the early health effects associated with a severe accident at a nuclear power station. The primary purpose of this study is to provide guidance on the variables to be considered in future review work to reduce the uncertainty in the important variables used in the calculation of reactor accident consequences. The effects of 34 imprecisely known input variables on the following reactor accident consequences are studied: number of early fatalities, number of cases of prodromal vomiting, population dose within 10 mi of the reactor, population dose within 1000 mi of the reactor, individual early fatality probability within 1 mi of the reactor, and maximum early fatality distance. When the predicted variables are considered collectively, the following input variables were found to be the dominant contributors to uncertainty: scaling factor for horizontal dispersion, dry deposition velocity, inhalation protection factor for nonevacuees, groundshine shielding factor for nonevacuees, early fatality hazard function alpha value for bone marrow exposure, and scaling factor for vertical dispersion.

  10. Coupled RELAP5 and CONTAIN accident analysis using PVM

    SciTech Connect

    Smith, K.A.; Baratta, A.J.; Robinson, G.E.

    1995-01-01

    This article describes the development of an integrated accident analysis capability considering both reactor vessel and containment system responses. This integrated package, which uses the RELAP5 and CONTAIN computer codes, provides the user with greater accuracy and modeling flexibility when compared with accident analyses using these codes separately. Multiprocessing, together with message-passing-based data transfer, enables these concurrent RELAP5 and CONTAIN calculations. The data transfer facilitates the coupling between the reactor vessel and containment portions of the calculation. The Parallel Virtual Machine software system running on a network of IBM RISC System/6000 workstations provided the multiprocessing capabilities required for this work. The results of an anticipated-transient-without-scram scenario for a boiling-water reactor nuclear power plant are provided. For the scenario analyzed, the containment temperatures and pressures that were predicted on the basis of the stand-alone codes and standard analysis methods were lower than those predicted with the use of the integrated code package. 12 refs., 10 figs., 7 tabs.

  11. Coupled Relap5 and Contain accident analysis using PVM

    SciTech Connect

    Smith, K.A.; Baratta, A.J.; Robinson, G.E.

    1995-10-01

    This article describes the development of an integrated accident analysis capability considering both reactor vessel and containment system responses. This integrated package, which uses the RELAP5 and CONTAIN computer codes, provides the user with greater accuracy and modeling flexibility when compared with accident analyses using these codes separately. Multiprocessing, together with message-passing-based data transfer, enables these concurrent RELAP5 and CONTAIN calculations. The data transfer facilitates the coupling between the reactor vessel and containment portions of the calculation. The Parallel Virtual Machine software system running on a network of IBM RISC System/6000 workstations provided the multiprocessing capabilities required for this work. The results of an anticipated-transient-without-scram scenario for a boiling-water reactor nuclear power plant are provided. For the scenario analyzed, the containment temperatures and pressures that were predicted on the basis of the stand-alone codes and standard analysis methods were lower (i.e., less conservative) than those predicted with the use of the integrated code package.

  12. Analysis of surface powered haulage accidents, January 1990--July 1996

    SciTech Connect

    Fesak, G.M.; Breland, R.M.; Spadaro, J.

    1996-12-31

    This report addresses surface haulage accidents that occurred between January 1990 and July 1996 involving haulage trucks (including over-the-road trucks), front-end-loaders, scrapers, utility trucks, water trucks, and other mobile haulage equipment. The study includes quarries, open pits and surface coal mines utilizing self-propelled mobile equipment to transport personnel, supplies, rock, overburden material, ore, mine waste, or coal for processing. A total of 4,397 accidents were considered. This report summarizes the major factors that led to the accidents and recommends accident prevention methods to reduce the frequency of these accidents.

  13. Uncertainty and sensitivity analysis of chronic exposure results with the MACCS reactor accident consequence model

    SciTech Connect

    Helton, J.C.; Johnson, J.D.; Rollstin, J.A.; Shiver, A.W.; Sprung, J.L.

    1995-01-01

    Uncertainty and sensitivity analysis techniques based on Latin hypercube sampling, partial correlation analysis and stepwise regression analysis are used in an investigation with the MACCS model of the chronic exposure pathways associated with a severe accident at a nuclear power station. The primary purpose of this study is to provide guidance on the variables to be considered in future review work to reduce the uncertainty in the important variables used in the calculation of reactor accident consequences. The effects of 75 imprecisely known input variables on the following reactor accident consequences are studied: crop growing season dose, crop long-term dose, water ingestion dose, milk growing season dose, long-term groundshine dose, long-term inhalation dose, total food pathways dose, total ingestion pathways dose, total long-term pathways dose, total latent cancer fatalities, area-dependent cost, crop disposal cost, milk disposal cost, population-dependent cost, total economic cost, condemnation area, condemnation population, crop disposal area and milk disposal area. When the predicted variables are considered collectively, the following input variables were found to be the dominant contributors to uncertainty: dry deposition velocity, transfer of cesium from animal feed to milk, transfer of cesium from animal feed to meat, ground concentration of Cs-134 at which the disposal of milk products will be initiated, transfer of Sr-90 from soil to legumes, maximum allowable ground concentration of Sr-90 for production of crops, fraction of cesium entering surface water that is consumed in drinking water, groundshine shielding factor, scale factor defining resuspension, dose reduction associated with decontamination, and ground concentration of 1-131 at which disposal of crops will be initiated due to accidents that occur during the growing season.

  14. An Analysis of U.S. Civil Rotorcraft Accidents by Cost and Injury (1990-1996)

    NASA Technical Reports Server (NTRS)

    Iseler, Laura; DeMaio, Joe; Rutkowski, Michael (Technical Monitor)

    2002-01-01

    A study of rotorcraft accidents was conducted to identify safety issues and research areas that might lead to a reduction in rotorcraft accidents and fatalities. The primary source of data was summaries of National Transportation Safety Board (NTSB) accident reports. From 1990 to 1996, the NTSB documented 1396 civil rotorcraft accidents in the United States in which 491 people were killed. The rotorcraft data were compared to airline and general aviation data to determine the relative safety of rotorcraft compared to other segments of the aviation industry. In depth analysis of the rotorcraft data addressed demographics, mission, and operational factors. Rotorcraft were found to have an accident rate about ten times that of commercial airliners and about the same as that of general aviation. The likelihood that an accident would be fatal was about equal for all three classes of operation. The most dramatic division in rotorcraft accidents is between flights flown by private pilots versus professional pilots. Private pilots, flying low cost aircraft in benign environments, have accidents that are due, in large part, to their own errors. Professional pilots, in contrast, are more likely to have accidents that are a result of exacting missions or use of specialized equipment. For both groups judgement error is more likely to lead to a fatal accident than are other types of causes. Several approaches to improving the rotorcraft accident rate are recommended. These mostly address improvement in the training of new pilots and improving the safety awareness of private pilots.

  15. An analysis of evacuation options for nuclear accidents

    SciTech Connect

    Tawil, J.J.; Strenge, D.L.; Schultz, R.W.

    1987-11-01

    In this report we consider the threat posed by the accidental release of radionuclides from a nuclear power plant. The objective is to establish relationships between radiation dose and the cost of evacuation under a wide variety of conditions. The dose can almost always be reduced by evacuating the population from a larger area. However, extending the evacuation zone outward will cause evacuation costs to increase. The purpose of this analysis was to provide the Environmental Protection Agency (EPA) a data base for evaluating whether implementation costs and risks averted could be used to justify evacuation at lower doses. The procedures used and results of these analyses are being made available as background information for use by others. We develop cost/dose relationships for 54 scenarios that are based upon the severity of the reactor accident, meteorological conditions during the release of radionuclides into the environment, and the angular width of the evacuation zone. The 54 scenarios are derived from combinations of three accident severity levels, six meteorological conditions and evacuation zone widths of 70{degree}, 90{degree}, and 180{degree}.

  16. An Accident Precursor Analysis Process Tailored for NASA Space Systems

    NASA Technical Reports Server (NTRS)

    Groen, Frank; Stamatelatos, Michael; Dezfuli, Homayoon; Maggio, Gaspare

    2010-01-01

    Accident Precursor Analysis (APA) serves as the bridge between existing risk modeling activities, which are often based on historical or generic failure statistics, and system anomalies, which provide crucial information about the failure mechanisms that are actually operative in the system and which may differ in frequency or type from those in the various models. These discrepancies between the models (perceived risk) and the system (actual risk) provide the leading indication of an underappreciated risk. This paper presents an APA process developed specifically for NASA Earth-to-Orbit space systems. The purpose of the process is to identify and characterize potential sources of system risk as evidenced by anomalous events which, although not necessarily presenting an immediate safety impact, may indicate that an unknown or insufficiently understood risk-significant condition exists in the system. Such anomalous events are considered accident precursors because they signal the potential for severe consequences that may occur in the future, due to causes that are discernible from their occurrence today. Their early identification allows them to be integrated into the overall system risk model used to intbrm decisions relating to safety.

  17. Decontamination analysis of the NUWAX-83 accident site using DECON

    SciTech Connect

    Tawil, J.J.

    1983-11-01

    This report presents an analysis of the site restoration options for the NUWAX-83 site, at which an exercise was conducted involving a simulated nuclear weapons accident. This analysis was performed using a computer program deveoped by Pacific Northwest Laboratory. The computer program, called DECON, was designed to assist personnel engaged in the planning of decontamination activities. The many features of DECON that are used in this report demonstrate its potential usefulness as a site restoration planning tool. Strategies that are analyzed with DECON include: (1) employing a Quick-Vac option, under which selected surfaces are vacuumed before they can be rained on; (2) protecting surfaces against precipitation; (3) prohibiting specific operations on selected surfaces; (4) requiring specific methods to be used on selected surfaces; (5) evaluating the trade-off between cleanup standards and decontamination costs; and (6) varying of the cleanup standards according to expected exposure to surface.

  18. Preliminary analysis of loss-of-coolant accident in Fukushima nuclear accident

    SciTech Connect

    Su'ud, Zaki; Anshari, Rio

    2012-06-06

    Loss-of-Coolant Accident (LOCA) in Boiling Water Reactor (BWR) especially on Fukushima Nuclear Accident will be discussed in this paper. The Tohoku earthquake triggered the shutdown of nuclear power reactors at Fukushima Nuclear Power station. Though shutdown process has been completely performed, cooling process, at much smaller level than in normal operation, is needed to remove decay heat from the reactor core until the reactor reach cold-shutdown condition. If LOCA happen at this condition, it will cause the increase of reactor fuel and other core temperatures and can lead to reactor core meltdown and exposure of radioactive material to the environment such as in the Fukushima Dai Ichi nuclear accident case. In this study numerical simulation has been performed to calculate pressure composition, water level and temperature distribution on reactor during this accident. There are two coolant regulating system that operational on reactor unit 1 at this accident, Isolation Condensers (IC) system and Safety Relief Valves (SRV) system. Average mass flow of steam to the IC system in this event is 10 kg/s and could keep reactor core from uncovered about 3,2 hours and fully uncovered in 4,7 hours later. There are two coolant regulating system at operational on reactor unit 2, Reactor Core Isolation Condenser (RCIC) System and Safety Relief Valves (SRV). Average mass flow of coolant that correspond this event is 20 kg/s and could keep reactor core from uncovered about 73 hours and fully uncovered in 75 hours later. There are three coolant regulating system at operational on reactor unit 3, Reactor Core Isolation Condenser (RCIC) system, High Pressure Coolant Injection (HPCI) system and Safety Relief Valves (SRV). Average mass flow of water that correspond this event is 15 kg/s and could keep reactor core from uncovered about 37 hours and fully uncovered in 40 hours later.

  19. The accident analysis of mobile mine machinery in Indian opencast coal mines.

    PubMed

    Kumar, R; Ghosh, A K

    2014-01-01

    This paper presents the analysis of large mining machinery related accidents in Indian opencast coal mines. The trends of coal production, share of mining methods in production, machinery deployment in open cast mines, size and population of machinery, accidents due to machinery, types and causes of accidents have been analysed from the year 1995 to 2008. The scrutiny of accidents during this period reveals that most of the responsible factors are machine reversal, haul road design, human fault, operator's fault, machine fault, visibility and dump design. Considering the types of machines, namely, dumpers, excavators, dozers and loaders together the maximum number of fatal accidents has been caused by operator's faults and human faults jointly during the period from 1995 to 2008. The novel finding of this analysis is that large machines with state-of-the-art safety system did not reduce the fatal accidents in Indian opencast coal mines.

  20. Analysis of Waste Leak and Toxic Chemical Release Accidents from Waste Feed Delivery (WFD) Diluent System

    SciTech Connect

    WILLIAMS, J.C.

    2000-09-15

    Radiological and toxicological consequences are calculated for 4 postulated accidents involving the Waste Feed Delivery (WFD) diluent addition systems. Consequences for the onsite and offsite receptor are calculated. This analysis contains technical information used to determine the accident consequences for the River Protection Project (RPP) Final Safety Analysis Report (FSAR).

  1. Radionuclide Analysis on Bamboos following the Fukushima Nuclear Accident

    PubMed Central

    Higaki, Takumi; Higaki, Shogo; Hirota, Masahiro; Akita, Kae; Hasezawa, Seiichiro

    2012-01-01

    In response to contamination from the recent Fukushima nuclear accident, we conducted radionuclide analysis on bamboos sampled from six sites within a 25 to 980 km radius of the Fukushima Daiichi nuclear power plant. Maximum activity concentrations of radiocesium 134Cs and 137Cs in samples from Fukushima city, 65 km away from the Fukushima Daiichi plant, were in excess of 71 and 79 kBq/kg, dry weight (DW), respectively. In Kashiwa city, 195 km away from the Fukushima Daiichi, the sample concentrations were in excess of 3.4 and 4.3 kBq/kg DW, respectively. In Toyohashi city, 440 km away from the Fukushima Daiichi, the concentrations were below the measurable limits of up to 4.5 Bq/kg DW. In the radiocesium contaminated samples, the radiocesium activity was higher in mature and fallen leaves than in young leaves, branches and culms. PMID:22496858

  2. Linguistic methodology for the analysis of aviation accidents

    NASA Technical Reports Server (NTRS)

    Goguen, J. A.; Linde, C.

    1983-01-01

    A linguistic method for the analysis of small group discourse, was developed and the use of this method on transcripts of commercial air transpot accidents is demonstrated. The method identifies the discourse types that occur and determine their linguistic structure; it identifies significant linguistic variables based upon these structures or other linguistic concepts such as speech act and topic; it tests hypotheses that support significance and reliability of these variables; and it indicates the implications of the validated hypotheses. These implications fall into three categories: (1) to train crews to use more nearly optimal communication patterns; (2) to use linguistic variables as indices for aspects of crew performance such as attention; and (3) to provide guidelines for the design of aviation procedures and equipment, especially those that involve speech.

  3. Hypothetical accident conditions thermal analysis of the 5320 package

    SciTech Connect

    Hensel, S.J.; Gromada, R.J.

    1995-12-31

    An axisymmetric model of the 5320 package was created to perform hypothetical accident conditions (HAC) thermal calculations. The analyses assume the 5320 package contains 359 grams of plutonium-238 (203 Watts) in the form of an oxide powder at a minimum density of 2.4 g/cc or at a maximum density of 11.2 g/cc. The solution from a non-solar 100 F ambient steady-state analysis was used as the initial conditions for the fire transient. A 30 minute 1,475 F fire transient followed by cooling via natural convection and thermal radiation to a 100 F non-solar environment was analyzed to determine peak component temperatures and vessel pressures. The 5320 package was considered to be horizontally suspended within the fire during the entire transient.

  4. Aircraft Accident Prevention: Loss-of-Control Analysis

    NASA Technical Reports Server (NTRS)

    Kwatny, Harry G.; Dongmo, Jean-Etienne T.; Chang, Bor-Chin; Bajpai, Guarav; Yasar, Murat; Belcastro, Christine M.

    2009-01-01

    The majority of fatal aircraft accidents are associated with loss-of-control . Yet the notion of loss-of-control is not well-defined in terms suitable for rigorous control systems analysis. Loss-of-control is generally associated with flight outside of the normal flight envelope, with nonlinear influences, and with an inability of the pilot to control the aircraft. The two primary sources of nonlinearity are the intrinsic nonlinear dynamics of the aircraft and the state and control constraints within which the aircraft must operate. In this paper we examine how these nonlinearities affect the ability to control the aircraft and how they may contribute to loss-of-control. Examples are provided using NASA s Generic Transport Model.

  5. Tobit analysis of vehicle accident rates on interstate highways.

    PubMed

    Anastasopoulos, Panagiotis Ch; Tarko, Andrew P; Mannering, Fred L

    2008-03-01

    There has been an abundance of research that has used Poisson models and its variants (negative binomial and zero-inflated models) to improve our understanding of the factors that affect accident frequencies on roadway segments. This study explores the application of an alternate method, tobit regression, by viewing vehicle accident rates directly (instead of frequencies) as a continuous variable that is left-censored at zero. Using data from vehicle accidents on Indiana interstates, the estimation results show that many factors relating to pavement condition, roadway geometrics and traffic characteristics significantly affect vehicle accident rates.

  6. Advanced accident sequence precursor analysis level 1 models

    SciTech Connect

    Sattison, M.B.; Thatcher, T.A.; Knudsen, J.K.; Schroeder, J.A.; Siu, N.O.

    1996-03-01

    INEL has been involved in the development of plant-specific Accident Sequence Precursor (ASP) models for the past two years. These models were developed for use with the SAPHIRE suite of PRA computer codes. They contained event tree/linked fault tree Level 1 risk models for the following initiating events: general transient, loss-of-offsite-power, steam generator tube rupture, small loss-of-coolant-accident, and anticipated transient without scram. Early in 1995 the ASP models were revised based on review comments from the NRC and an independent peer review. These models were released as Revision 1. The Office of Nuclear Regulatory Research has sponsored several projects at the INEL this fiscal year to further enhance the capabilities of the ASP models. Revision 2 models incorporates more detailed plant information into the models concerning plant response to station blackout conditions, information on battery life, and other unique features gleaned from an Office of Nuclear Reactor Regulation quick review of the Individual Plant Examination submittals. These models are currently being delivered to the NRC as they are completed. A related project is a feasibility study and model development of low power/shutdown (LP/SD) and external event extensions to the ASP models. This project will establish criteria for selection of LP/SD and external initiator operational events for analysis within the ASP program. Prototype models for each pertinent initiating event (loss of shutdown cooling, loss of inventory control, fire, flood, seismic, etc.) will be developed. A third project concerns development of enhancements to SAPHIRE. In relation to the ASP program, a new SAPHIRE module, GEM, was developed as a specific user interface for performing ASP evaluations. This module greatly simplifies the analysis process for determining the conditional core damage probability for a given combination of initiating events and equipment failures or degradations.

  7. Analysis of injury severity and vehicle occupancy in truck- and non-truck-involved accidents.

    PubMed

    Chang, L Y; Mannering, F

    1999-09-01

    The impact that large trucks have on accident severity has long been a concern in the accident analysis literature. One important measure of accident severity is the most severely injured occupant in the vehicle. Such data are routinely collected in state accident data files in the U.S. Among the many risk factors that determine the most severe level of injury sustained by vehicle occupants, the number of occupants in the vehicle is an important factor. These effects can be significant because vehicles with higher occupancies have an increased likelihood of having someone seriously injured. This paper studies the occupancy/injury severity relationship using Washington State accident data. The effects of large trucks, which are shown to have a significant impact on the most severely injured vehicle occupant, are accounted for by separately estimating nested logit models for truck-involved accidents and for non-truck-involved accidents. The estimation results uncover important relationships between various risk factors and occupant injury. In addition, by comparing the accident characteristics between truck-involved accidents and non-truck-involved accidents, the risk factors unique to large trucks are identified along with the relative importance of such factors. The findings of this study demonstrate that nested logit modeling, which is able to take into account vehicle occupancy effects and identify a broad range of factors that influence occupant injury, is a promising methodological approach.

  8. Rehabilitation of soils and surface after a nuclear accident: Some techniques tried in the Chernobyl zone

    SciTech Connect

    Jouve, A.; Maubert, H.; Kutlakhamedov, Y.

    1993-12-31

    Six years after the Chernobyl accident, the major part of deposited radio nuclides remains in the 3 or 4 cm of the topsoil of abandoned fields in the chernobyl zone. The Decontaminating Vegetal Network allows a layer of few centimeters of the top soil to be removed with a turf harvester. The efficiency observed at Chernobyl was 97% for cesium-137 and strontium-90. After scraping the soil with the turf harvester, the bare soil must be covered and re-grown in order to prevent wind erosion of the sandy soil. A trial spraying of polyacrylamide on the soil was carried out. This technique seems promising. Trials of bio-decontamination of the removed turf using anaerobic degradation were also carried out. This experiment provided an opportunity to measure in real conditions the transfer of radionuclides in the Chernobyl zone.

  9. Swimming pool immersion accidents: an analysis from the Brisbane Drowning Study

    PubMed Central

    Pearn, John H; Nixon, James

    1997-01-01

    An analysis of a consecutive series of 66 swimming pool immersion accidents is presented; 74% of these occurred in in-ground swimming pools. The estimated accident rate per pool is fives times greater for in-ground pools compared with above-ground pools, where pools are inadequately fenced. Backyard swimming pools account for 74% of pool accidents. Motel and caravan park pools account for 9% of childhood immersion accidents, but the survival rate (17%) is very low. Fifty per cent of pool accidents occur in the family's own backyard pool, and 13.6% in a neighbour's pool; in the latter the survival rate is still low at only 33%. In only one of the 66 cases was there an adequate safety fence; in 76% of cases there was no fence or barrier whatsoever. Tables of swimming pool accidents by age, season, site, and outcome are presented. PMID:9493630

  10. Progress in accident analysis of the HYLIFE-II inertial fusion energy power plant design

    SciTech Connect

    Reyes, S; Latkowski, J F; Gomez del Rio, J; Sanz, J

    2000-10-11

    The present work continues our effort to perform an integrated safety analysis for the HYLIFE-II inertial fusion energy (IFE) power plant design. Recently we developed a base case for a severe accident scenario in order to calculate accident doses for HYLIFE-II. It consisted of a total loss of coolant accident (LOCA) in which all the liquid flibe (Li{sub 2}BeF{sub 4}) was lost at the beginning of the accident. Results showed that the off-site dose was below the limit given by the DOE Fusion Safety Standards for public protection in case of accident, and that his dose was dominated by the tritium released during the accident.

  11. Minimum Accident of Concern - A Different Basis for CAS Analysis

    SciTech Connect

    Biswas, D.

    2002-01-31

    A Criticality Alarm System is normally designed to detect immediately the minimum accident of concern. This report covers the methodology to establish a different minimum accident of concern developed for shielded facilities and applied to a case of the canyon sump excursion in a Savannah River Site facility.

  12. Multi-technique characterization of a nuclear bomb particle from the Palomares accident.

    PubMed

    Pöllänen, R; Ketterer, M E; Lehto, S; Hokkanen, M; Ikäheimonen, T K; Siiskonen, T; Moring, M; Rubio Montero, M P; Martín Sánchez, A

    2006-01-01

    A January 1966 accident dispersed Pu and other nuclear bomb materials in the vicinity of Palomares, a village in southeastern Spain. Radioactive particles were identified in a soil sample collected in 1998 and analytical results obtained from one of the isolated particles are presented here. Isolation of the particle was performed using gamma-ray spectrometry and imaging plates. Scanning electron microscopy with X-ray microanalysis revealed the presence of U and Pu as well as Pb and Fe in the particle of approximately 10microm diameter. Radioisotopes of U, Pu, and Am were quantified using radiometric methods, inductively coupled plasma mass spectrometry and secondary ion mass spectrometry. The elevated (235)U/(238)U atom ratio indicates enriched U, and the Pu atom ratios are consistent with weapons-grade material. This work demonstrates that the analysis of individual particles provides information not available through bulk sample analysis.

  13. An analysis of three weather-related aircraft accidents

    NASA Technical Reports Server (NTRS)

    Fujita, T. T.; Caracena, F.

    1977-01-01

    Two aircraft accidents in 1975, one at John F. Kennedy International Airport in New York City on 24 June and the other at Stapleton International Airport in Denver on 7 August, were examined in detail. A third accident on 23 June 1976 at Philadelphia International Airport is being investigated. Amazingly, there was a spearhead echo just to the north of each accident site. The echoes formed from 5 to 50 min in advance of the accident and moved faster than other echoes in the vicinity. These echoes were photographed by National Weather Service radars, 130-205 km away. At closer ranges, however, one or more circular echoes were depicted by airborne and ground radars. These cells were only 3-5 km in diameter, but they were accompanied by downdrafts of extreme intensity, called downbursts. All accidents occurred as aircraft, either descending or climbing, lost altitude while experiencing strong wind shear inside downburst cells.

  14. GPHS-RTG launch accident analysis for Galileo and Ulysses

    NASA Astrophysics Data System (ADS)

    Bradshaw, C. Thomas

    1991-01-01

    This paper presents the safety program conducted to determine the response of the General Purpose Heat Source (GPHS) Radioisotope Thermoelectric Generator (RTG) to potential launch accidents of the Space Shuttle for the Galileo and Ulysses missions. The National Aeronautics and Space Administration (NASA) provided definition of the Shuttle potential accidents and characterized the environments. The Launch Accident Scenario Evaluation Program (LASEP) was developed by GE to analyze the RTG response to these accidents. RTG detailed response to Solid Rocket Booster (SRB) fragment impacts, as well as to other types of impact, was obtained from an extensive series of hydrocode analyses. A comprehensive test program was conducted also to determine RTG response to the accident environments. The hydrocode response analyses coupled with the test data base provided the broad range response capability which was implemented in LASEP.

  15. An Evidential Reasoning-Based CREAM to Human Reliability Analysis in Maritime Accident Process.

    PubMed

    Wu, Bing; Yan, Xinping; Wang, Yang; Soares, C Guedes

    2017-01-09

    This article proposes a modified cognitive reliability and error analysis method (CREAM) for estimating the human error probability in the maritime accident process on the basis of an evidential reasoning approach. This modified CREAM is developed to precisely quantify the linguistic variables of the common performance conditions and to overcome the problem of ignoring the uncertainty caused by incomplete information in the existing CREAM models. Moreover, this article views maritime accident development from the sequential perspective, where a scenario- and barrier-based framework is proposed to describe the maritime accident process. This evidential reasoning-based CREAM approach together with the proposed accident development framework are applied to human reliability analysis of a ship capsizing accident. It will facilitate subjective human reliability analysis in different engineering systems where uncertainty exists in practice.

  16. A Human Factors Analysis of Fatal and Serious Injury Accidents in Alaska, 2004-2009

    DTIC Science & Technology

    2011-12-01

    During. the.analysis,.these.were.sometimes.referred.to.as.“ moose . 8..... stalls .”.All.but.one.of.these.accidents.ended.when.the...to.be.fair,. moose -watching.was.not.the.only.distraction .. Several.of.these.accidents.did.involve.looking.at.wildlife. (sheep,.wolves,.a.whale.bone

  17. Analysis of Construction Accidents in Turkey and Responsible Parties

    PubMed Central

    GÜRCANLI, G. Emre; MÜNGEN, Uğur

    2013-01-01

    Construction is one of the world’s biggest industry that includes jobs as diverse as building, civil engineering, demolition, renovation, repair and maintenance. Construction workers are exposed to a wide variety of hazards. This study analyzes 1,117 expert witness reports which were submitted to criminal and labour courts. These reports are from all regions of the country and cover the period 1972–2008. Accidents were classified by the consequence of the incident, time and main causes of the accident, construction type, occupation of the victim, activity at time of the accident and party responsible for the accident. Falls (54.1%), struck by thrown/falling object (12.9%), structural collapses (9.9%) and electrocutions (7.5%) rank first four places. The accidents were most likely between the hours 15:00 and 17:00 (22.6%), 10:00–12:00 (18.7%) and just after the lunchtime (9.9%). Additionally, the most common accidents were further divided into sub-types. Expert-witness assessments were used to identify the parties at fault and what acts of negligence typically lead to accidents. Nearly two thirds of the faulty and negligent acts are carried out by the employers and employees are responsible for almost one third of all cases. PMID:24077446

  18. Analysis of construction accidents in Turkey and responsible parties.

    PubMed

    Gürcanli, G Emre; Müngen, Uğur

    2013-01-01

    Construction is one of the world's biggest industry that includes jobs as diverse as building, civil engineering, demolition, renovation, repair and maintenance. Construction workers are exposed to a wide variety of hazards. This study analyzes 1,117 expert witness reports which were submitted to criminal and labour courts. These reports are from all regions of the country and cover the period 1972-2008. Accidents were classified by the consequence of the incident, time and main causes of the accident, construction type, occupation of the victim, activity at time of the accident and party responsible for the accident. Falls (54.1%), struck by thrown/falling object (12.9%), structural collapses (9.9%) and electrocutions (7.5%) rank first four places. The accidents were most likely between the hours 15:00 and 17:00 (22.6%), 10:00-12:00 (18.7%) and just after the lunchtime (9.9%). Additionally, the most common accidents were further divided into sub-types. Expert-witness assessments were used to identify the parties at fault and what acts of negligence typically lead to accidents. Nearly two thirds of the faulty and negligent acts are carried out by the employers and employees are responsible for almost one third of all cases.

  19. A POTENTIAL APPLICATION OF UNCERTAINTY ANALYSIS TO DOE-STD-3009-94 ACCIDENT ANALYSIS

    SciTech Connect

    Palmrose, D E; Yang, J M

    2007-05-10

    The objective of this paper is to assess proposed transuranic waste accident analysis guidance and recent software improvements in a Windows-OS version of MACCS2 that allows the inputting of parameter uncertainty. With this guidance and code capability, there is the potential to perform a quantitative uncertainty assessment of unmitigated accident releases with respect to the 25 rem Evaluation Guideline (EG) of DOE-STD-3009-94 CN3 (STD-3009). Historically, the classification of safety systems in a U.S. Department of Energy (DOE) nuclear facility's safety basis has involved how subject matter experts qualitatively view uncertainty in the STD-3009 Appendix A accident analysis methodology. Specifically, whether consequence uncertainty could be larger than previously evaluated so the site-specific accident consequences may challenge the EG. This paper assesses whether a potential uncertainty capability for MACCS2 could provide a stronger technical basis as to when the consequences from a design basis accident (DBA) truly challenges the 25 rem EG.

  20. Accidents at Work and Costs Analysis: A Field Study in a Large Italian Company

    PubMed Central

    BATTAGLIA, Massimo; FREY, Marco; PASSETTI, Emilio

    2014-01-01

    Accidents at work are still a heavy burden in social and economic terms, and action to improve health and safety standards at work offers great potential gains not only to employers, but also to individuals and society as a whole. However, companies often are not interested to measure the costs of accidents even if cost information may facilitate preventive occupational health and safety management initiatives. The field study, carried out in a large Italian company, illustrates technical and organisational aspects associated with the implementation of an accident costs analysis tool. The results indicate that the implementation (and the use) of the tool requires a considerable commitment by the company, that accident costs analysis should serve to reinforce the importance of health and safety prevention and that the economic dimension of accidents is substantial. The study also suggests practical ways to facilitate the implementation and the moral acceptance of the accounting technology. PMID:24869894

  1. Accidents at work and costs analysis: a field study in a large Italian company.

    PubMed

    Battaglia, Massimo; Frey, Marco; Passetti, Emilio

    2014-01-01

    Accidents at work are still a heavy burden in social and economic terms, and action to improve health and safety standards at work offers great potential gains not only to employers, but also to individuals and society as a whole. However, companies often are not interested to measure the costs of accidents even if cost information may facilitate preventive occupational health and safety management initiatives. The field study, carried out in a large Italian company, illustrates technical and organisational aspects associated with the implementation of an accident costs analysis tool. The results indicate that the implementation (and the use) of the tool requires a considerable commitment by the company, that accident costs analysis should serve to reinforce the importance of health and safety prevention and that the economic dimension of accidents is substantial. The study also suggests practical ways to facilitate the implementation and the moral acceptance of the accounting technology.

  2. Sodium fast reactor gaps analysis of computer codes and models for accident analysis and reactor safety.

    SciTech Connect

    Carbajo, Juan; Jeong, Hae-Yong; Wigeland, Roald; Corradini, Michael; Schmidt, Rodney Cannon; Thomas, Justin; Wei, Tom; Sofu, Tanju; Ludewig, Hans; Tobita, Yoshiharu; Ohshima, Hiroyuki; Serre, Frederic

    2011-06-01

    This report summarizes the results of an expert-opinion elicitation activity designed to qualitatively assess the status and capabilities of currently available computer codes and models for accident analysis and reactor safety calculations of advanced sodium fast reactors, and identify important gaps. The twelve-member panel consisted of representatives from five U.S. National Laboratories (SNL, ANL, INL, ORNL, and BNL), the University of Wisconsin, the KAERI, the JAEA, and the CEA. The major portion of this elicitation activity occurred during a two-day meeting held on Aug. 10-11, 2010 at Argonne National Laboratory. There were two primary objectives of this work: (1) Identify computer codes currently available for SFR accident analysis and reactor safety calculations; and (2) Assess the status and capability of current US computer codes to adequately model the required accident scenarios and associated phenomena, and identify important gaps. During the review, panel members identified over 60 computer codes that are currently available in the international community to perform different aspects of SFR safety analysis for various event scenarios and accident categories. A brief description of each of these codes together with references (when available) is provided. An adaptation of the Predictive Capability Maturity Model (PCMM) for computational modeling and simulation is described for use in this work. The panel's assessment of the available US codes is presented in the form of nine tables, organized into groups of three for each of three risk categories considered: anticipated operational occurrences (AOOs), design basis accidents (DBA), and beyond design basis accidents (BDBA). A set of summary conclusions are drawn from the results obtained. At the highest level, the panel judged that current US code capabilities are adequate for licensing given reasonable margins, but expressed concern that US code development activities had stagnated and that the

  3. Risk analysis of emergent water pollution accidents based on a Bayesian Network.

    PubMed

    Tang, Caihong; Yi, Yujun; Yang, Zhifeng; Sun, Jie

    2016-01-01

    To guarantee the security of water quality in water transfer channels, especially in open channels, analysis of potential emergent pollution sources in the water transfer process is critical. It is also indispensable for forewarnings and protection from emergent pollution accidents. Bridges above open channels with large amounts of truck traffic are the main locations where emergent accidents could occur. A Bayesian Network model, which consists of six root nodes and three middle layer nodes, was developed in this paper, and was employed to identify the possibility of potential pollution risk. Dianbei Bridge is reviewed as a typical bridge on an open channel of the Middle Route of the South to North Water Transfer Project where emergent traffic accidents could occur. Risk of water pollutions caused by leakage of pollutants into water is focused in this study. The risk for potential traffic accidents at the Dianbei Bridge implies a risk for water pollution in the canal. Based on survey data, statistical analysis, and domain specialist knowledge, a Bayesian Network model was established. The human factor of emergent accidents has been considered in this model. Additionally, this model has been employed to describe the probability of accidents and the risk level. The sensitive reasons for pollution accidents have been deduced. The case has also been simulated that sensitive factors are in a state of most likely to lead to accidents.

  4. Analysis of Loss-of-Coolant Accidents in the NBSR

    SciTech Connect

    Baek J. S.; Cheng L.; Diamond, D.

    2014-05-23

    This report documents calculations of the fuel cladding temperature during loss-of-coolant accidents in the NBSR. The probability of a pipe failure is small and procedures exist to minimize the loss of water and assure emergency cooling water flows into the reactor core during such an event. Analysis in the past has shown that the emergency cooling water would provide adequate cooling if the water filled the flow channels within the fuel elements. The present analysis is to determine if there is adequate cooling if the water drains from the flow channels. Based on photographs of how the emergency water flows into the fuel elements from the distribution pan, it can be assumed that this water does not distribute uniformly across the flow channels but rather results in a liquid film flowing downward on the inside of one of the side plates in each fuel element and only wets the edges of the fuel plates. An analysis of guillotine breaks shows the cladding temperature remains below the blister temperature in fuel plates in the upper section of the fuel element. In the lower section, the fuel plates are also cooled by water outside the element that is present due to the hold-up pan and temperatures are lower than in the upper section. For small breaks, the simulation results show that the fuel elements are always cooled on the outside even in the upper section and the cladding temperature cannot be higher than the blister temperature. The above results are predicated on assumptions that are examined in the study to see their influence on fuel temperature.

  5. [Paragliding accidents--a prospective analysis in Swiss mountain regions].

    PubMed

    Lautenschlager, S; Karli, U; Matter, P

    1993-01-01

    During the period from 1.1 to 31.12.90, 86 injuries associated with paragliding were analysed in a prospective study in 12 different Swiss hospitals with reference to causes, patterns, and frequencies. Spine injuries (36%) and lesions of the lower extremities (35%) were diagnosed most frequently. Surprisingly no neurological complications occurred, which is possibly explained by the solitary axial trauma. In 15 cases very severe malleolar fractures required surgical intervention. One accident was fatal due to a lung rupture. 60% of all accidents happened during the landing phase, 26% at launching and 14% at flight. Half of the pilots were affected in their primary training course. Most accidents were due to an in-flight error of judgement, such as incorrect estimation of wind conditions and a choice of unfavourable landing sites. In contrast to early reports of hang-gliding injuries, only one accident was due to an equipment failure, namely a ruptured steering line. In more than a third of all accidents, the used paraglider was not in correct correlation with the pilot's weight and experience. Inspired by the desire for a long flight, gliders of too large surface-areas were often used, leading to a more unstable flight. To reduce the frequency of paragliding injuries, an accurate choice of equipment and increased attention to environmental factors is mandatory. Furthermore education-programs should focus more on intensifying the pilot's mental and practical skills.

  6. Action Plan for updated Chapter 15 Accident Analysis in the SRS Production Reactor SAR

    SciTech Connect

    Hightower, N.T. III; Burnett, T.W.

    1989-11-15

    This report describes the Action Plan for the upgrade of the Chapter 15 Accident Analysis in the SRS Production Reactor SAR required for K-Restart. This Action Plan will be updated periodically to reflect task accomplishments and issue resolutions.

  7. Aircraft Accidents: Trends in Aerospace Medical Investigation Techniques (Les Accidents d’Aeronefs: les Tendances en Techniques d’Investigation Medicale)

    DTIC Science & Technology

    1992-09-01

    transduction m6cano-nerveuse r~duire los risques de d~sorientation. L’introduction de otolithique. En effet, par principe, les capteurs otolithiques...psychological factors in "The Dark Nigth Takeoff accident". capteurs du monde r~el, mais aussi celle d’un risque .de Aerospace Med. 41 (5) pp: 553-6 d...temps d’incapacltation capteurs permettant le suivi des correspondant A la reduction de param~tres physiques essentiels I’activit6 motrice spontan~e et un

  8. Preliminary Assessment of ICRP Dose Conversion Factor Recommendations for Accident Analysis Applications

    SciTech Connect

    Vincent, A.M.

    2002-03-13

    Accident analysis for U.S. Department of Energy (DOE) nuclear facilities is an integral part of the overall safety basis developed by the contractor to demonstrate facility operation can be conducted safely. An appropriate documented safety analysis for a facility discusses accident phenomenology, quantifies source terms arising from postulated process upset conditions, and applies a standardized, internationally-recognized database of dose conversion factors (DCFs) to evaluate radiological conditions to offsite receptors.

  9. School sports accidents: analysis of causes, modes, and frequencies.

    PubMed

    Kelm, J; Ahlhelm, F; Pape, D; Pitsch, W; Engel, C

    2001-01-01

    About 5% of all school children are seriously injured during physical education every year. Because of its influence on children's attitude toward sports and the economic aspects, an evaluation of causes and medical consequences is necessary. In this study, 213 school sports accidents were investigated. Besides diagnosis, the localization of injuries, as well as the duration of the sick leave were documented. Average age of injured students was 13 years. Most of the injured students blamed themselves for the accident. The most common injuries were sprains, contusions, and fractures. Main reasons for the accidents were faults in basic motion training. Playing soccer and basketball were the most frequent reasons for injuries. The upper extremity was more frequently involved than the lower extremity. Sports physicians and teachers should work out a program outlining the individual needs and capabilities of the injured students to reintegrate them into physical education.

  10. Accident Precursor Analysis and Management: Reducing Technological Risk Through Diligence

    NASA Technical Reports Server (NTRS)

    Phimister, James R. (Editor); Bier, Vicki M. (Editor); Kunreuther, Howard C. (Editor)

    2004-01-01

    Almost every year there is at least one technological disaster that highlights the challenge of managing technological risk. On February 1, 2003, the space shuttle Columbia and her crew were lost during reentry into the atmosphere. In the summer of 2003, there was a blackout that left millions of people in the northeast United States without electricity. Forensic analyses, congressional hearings, investigations by scientific boards and panels, and journalistic and academic research have yielded a wealth of information about the events that led up to each disaster, and questions have arisen. Why were the events that led to the accident not recognized as harbingers? Why were risk-reducing steps not taken? This line of questioning is based on the assumption that signals before an accident can and should be recognized. To examine the validity of this assumption, the National Academy of Engineering (NAE) undertook the Accident Precursors Project in February 2003. The project was overseen by a committee of experts from the safety and risk-sciences communities. Rather than examining a single accident or incident, the committee decided to investigate how different organizations anticipate and assess the likelihood of accidents from accident precursors. The project culminated in a workshop held in Washington, D.C., in July 2003. This report includes the papers presented at the workshop, as well as findings and recommendations based on the workshop results and committee discussions. The papers describe precursor strategies in aviation, the chemical industry, health care, nuclear power and security operations. In addition to current practices, they also address some areas for future research.

  11. The Fukushima accident and travel medicine--analysis and recommendations.

    PubMed

    Scholl, C; Lieberz, W; Jansing, P; Küpper, T

    2013-01-01

    The accident at the nuclear site in Fukushima has fostered a fear of the consequences of radioactive contamination among many, especially regarding travel to Japan and the import of Japanese goods. We give a general overview of the assessment of the effects of ionizing radiation and a summary of the consequences of the Japanese accident. We report the results of the measurement of radionuclide intake among travelers returning from Japan, carried out at the whole-body counter of the Institute for Work Design of North Rhine-Westphalia (LIA.NRW) in Düsseldorf.

  12. ACCIDENT ANALYSES & CONTROL OPTIONS IN SUPPORT OF THE SLUDGE WATER SYSTEM SAFETY ANALYSIS

    SciTech Connect

    WILLIAMS, J.C.

    2003-11-15

    This report documents the accident analyses and nuclear safety control options for use in Revision 7 of HNF-SD-WM-SAR-062, ''K Basins Safety Analysis Report'' and Revision 4 of HNF-SD-SNF-TSR-001, ''Technical Safety Requirements - 100 KE and 100 KW Fuel Storage Basins''. These documents will define the authorization basis for Sludge Water System (SWS) operations. This report follows the guidance of DOE-STD-3009-94, ''Preparation Guide for US. Department of Energy Nonreactor Nuclear Facility Safety Analysis Reports'', for calculating onsite and offsite consequences. The accident analysis summary is shown in Table ES-1 below. While this document describes and discusses potential control options to either mitigate or prevent the accidents discussed herein, it should be made clear that the final control selection for any accident is determined and presented in HNF-SD-WM-SAR-062.

  13. Analysis of Kuosheng Station Blackout Accident Using MELCOR 1.8.4

    SciTech Connect

    Wang, S.-J.; Chien, C.-S.; Wang, T.-C.; Chiang, K.-S

    2000-11-15

    The MELCOR code, developed by Sandia National Laboratories, is a fully integrated, relatively fast-running code that models the progression of severe accidents in commercial light water nuclear power plants (NPPs).A specific station blackout (SBO) accident for Kuosheng (BWR-6) NPP is simulated using the MELCOR 1.8.4 code. The MELCOR input deck for Kuosheng NPP is established based on Kuosheng NPP design data and the MELCOR users' guides. The initial steady-state conditions are generated with a developed self-initialization algorithm. The main severe accident phenomena and the fission product release fractions associated with the SBO accident were simulated. The predicted results are plausible and as expected in light of current understanding of severe accident phenomena. The uncertainty of this analysis is briefly discussed. The important features of the MELCOR 1.8.4 are described. The estimated results provide useful information for the probabilistic risk assessment (PRA) of Kuosheng NPP. This tool will be applied to the PRA, the severe accident analysis, and the severe accident management study of Kuosheng NPP in the near future.

  14. DYNAMIC ANALYSIS OF HANFORD UNIRRADIATED FUEL PACKAGE SUBJECTED TO SEQUENTIAL LATERAL LOADS IN HYPOTHETICAL ACCIDENT CONDITIONS

    SciTech Connect

    Wu, T

    2008-04-30

    Large fuel casks present challenges when evaluating their performance in the Hypothetical Accident Conditions (HAC) specified in the Code of Federal Regulations Title 10 part 71 (10CFR71). Testing is often limited by cost, difficulty in preparing test units and the limited availability of facilities which can carry out such tests. In the past, many casks were evaluated without testing by using simplified analytical methods. This paper presents a numerical technique for evaluating the dynamic responses of large fuel casks subjected to sequential HAC loading. A nonlinear dynamic analysis was performed for a Hanford Unirradiated Fuel Package (HUFP) [1] to evaluate the cumulative damage after the hypothetical accident Conditions of a 30-foot lateral drop followed by a 40-inch lateral puncture as specified in 10CFR71. The structural integrity of the containment vessel is justified based on the analytical results in comparison with the stress criteria, specified in the ASME Code, Section III, Appendix F [2], for Level D service loads. The analyzed cumulative damages caused by the sequential loading of a 30-foot lateral drop and a 40-inch lateral puncture are compared with the package test data. The analytical results are in good agreement with the test results.

  15. Structural Analysis for the American Airlines Flight 587 Accident Investigation: Global Analysis

    NASA Technical Reports Server (NTRS)

    Young, Richard D.; Lovejoy, Andrew E.; Hilburger, Mark W.; Moore, David F.

    2005-01-01

    NASA Langley Research Center (LaRC) supported the National Transportation Safety Board (NTSB) in the American Airlines Flight 587 accident investigation due to LaRC's expertise in high-fidelity structural analysis and testing of composite structures and materials. A Global Analysis Team from LaRC reviewed the manufacturer s design and certification procedures, developed finite element models and conducted structural analyses, and participated jointly with the NTSB and Airbus in subcomponent tests conducted at Airbus in Hamburg, Germany. The Global Analysis Team identified no significant or obvious deficiencies in the Airbus certification and design methods. Analysis results from the LaRC team indicated that the most-likely failure scenario was failure initiation at the right rear main attachment fitting (lug), followed by an unstable progression of failure of all fin-to-fuselage attachments and separation of the VTP from the aircraft. Additionally, analysis results indicated that failure initiates at the final observed maximum fin loading condition in the accident, when the VTP was subjected to loads that were at minimum 1.92 times the design limit load condition for certification. For certification, the VTP is only required to support loads of 1.5 times design limit load without catastrophic failure. The maximum loading during the accident was shown to significantly exceed the certification requirement. Thus, the structure appeared to perform in a manner consistent with its design and certification, and failure is attributed to VTP loads greater than expected.

  16. Sensitivity analysis of radionuclides atmospheric dispersion following the Fukushima accident

    NASA Astrophysics Data System (ADS)

    Girard, Sylvain; Korsakissok, Irène; Mallet, Vivien

    2014-05-01

    Atmospheric dispersion models are used in response to accidental releases with two purposes: - minimising the population exposure during the accident; - complementing field measurements for the assessment of short and long term environmental and sanitary impacts. The predictions of these models are subject to considerable uncertainties of various origins. Notably, input data, such as meteorological fields or estimations of emitted quantities as function of time, are highly uncertain. The case studied here is the atmospheric release of radionuclides following the Fukushima Daiichi disaster. The model used in this study is Polyphemus/Polair3D, from which derives IRSN's operational long distance atmospheric dispersion model ldX. A sensitivity analysis was conducted in order to estimate the relative importance of a set of identified uncertainty sources. The complexity of this task was increased by four characteristics shared by most environmental models: - high dimensional inputs; - correlated inputs or inputs with complex structures; - high dimensional output; - multiplicity of purposes that require sophisticated and non-systematic post-processing of the output. The sensitivities of a set of outputs were estimated with the Morris screening method. The input ranking was highly dependent on the considered output. Yet, a few variables, such as horizontal diffusion coefficient or clouds thickness, were found to have a weak influence on most of them and could be discarded from further studies. The sensitivity analysis procedure was also applied to indicators of the model performance computed on a set of gamma dose rates observations. This original approach is of particular interest since observations could be used later to calibrate the input variables probability distributions. Indeed, only the variables that are influential on performance scores are likely to allow for calibration. An indicator based on emission peaks time matching was elaborated in order to complement

  17. Accident Analysis for the NIST Research Reactor Before and After Fuel Conversion

    SciTech Connect

    Baek J.; Diamond D.; Cuadra, A.; Hanson, A.L.; Cheng, L-Y.; Brown, N.R.

    2012-09-30

    Postulated accidents have been analyzed for the 20 MW D2O-moderated research reactor (NBSR) at the National Institute of Standards and Technology (NIST). The analysis has been carried out for the present core, which contains high enriched uranium (HEU) fuel and for a proposed equilibrium core with low enriched uranium (LEU) fuel. The analyses employ state-of-the-art calculational methods. Three-dimensional Monte Carlo neutron transport calculations were performed with the MCNPX code to determine homogenized fuel compositions in the lower and upper halves of each fuel element and to determine the resulting neutronic properties of the core. The accident analysis employed a model of the primary loop with the RELAP5 code. The model includes the primary pumps, shutdown pumps outlet valves, heat exchanger, fuel elements, and flow channels for both the six inner and twenty-four outer fuel elements. Evaluations were performed for the following accidents: (1) control rod withdrawal startup accident, (2) maximum reactivity insertion accident, (3) loss-of-flow accident resulting from loss of electrical power with an assumption of failure of shutdown cooling pumps, (4) loss-of-flow accident resulting from a primary pump seizure, and (5) loss-of-flow accident resulting from inadvertent throttling of a flow control valve. In addition, natural circulation cooling at low power operation was analyzed. The analysis shows that the conversion will not lead to significant changes in the safety analysis and the calculated minimum critical heat flux ratio and maximum clad temperature assure that there is adequate margin to fuel failure.

  18. Study of Benefits of Passenger Protective Breathing Equipment from Analysis of Past Accidents

    DTIC Science & Technology

    1988-03-01

    analysis of worldwide transport aircraft accidents involving fire. BACKGROUND. During a cabin fire, smoke and toxic gases may inhibit or prevent passenger...aviation industry focused upon smoke and toxic gases as causal factors of passenger incapacitation, resulting in failure to evacuate the aircraft before... gases . Protective breathing equipment (PBE) is being reevaluated in response to the United Kingdom’s (UK) Department of Transport’s Accident

  19. Advanced accident sequence precursor analysis level 2 models

    SciTech Connect

    Galyean, W.J.; Brownson, D.A.; Rempe, J.L.

    1996-03-01

    The U.S. Nuclear Regulatory Commission Accident Sequence Precursor program pursues the ultimate objective of performing risk significant evaluations on operational events (precursors) occurring in commercial nuclear power plants. To achieve this objective, the Office of Nuclear Regulatory Research is supporting the development of simple probabilistic risk assessment models for all commercial nuclear power plants (NPP) in the U.S. Presently, only simple Level 1 plant models have been developed which estimate core damage frequencies. In order to provide a true risk perspective, the consequences associated with postulated core damage accidents also need to be considered. With the objective of performing risk evaluations in an integrated and consistent manner, a linked event tree approach which propagates the front end results to back end was developed. This approach utilizes simple plant models that analyze the response of the NPP containment structure in the context of a core damage accident, estimate the magnitude and timing of a radioactive release to the environment, and calculate the consequences for a given release. Detailed models and results from previous studies, such as the NUREG-1150 study, are used to quantify these simple models. These simple models are then linked to the existing Level 1 models, and are evaluated using the SAPHIRE code. To demonstrate the approach, prototypic models have been developed for a boiling water reactor, Peach Bottom, and a pressurized water reactor, Zion.

  20. Accident sequence precursor analysis level 2/3 model development

    SciTech Connect

    Lui, C.H.; Galyean, W.J.; Brownson, D.A.

    1997-02-01

    The US Nuclear Regulatory Commission`s Accident Sequence Precursor (ASP) program currently uses simple Level 1 models to assess the conditional core damage probability for operational events occurring in commercial nuclear power plants (NPP). Since not all accident sequences leading to core damage will result in the same radiological consequences, it is necessary to develop simple Level 2/3 models that can be used to analyze the response of the NPP containment structure in the context of a core damage accident, estimate the magnitude of the resulting radioactive releases to the environment, and calculate the consequences associated with these releases. The simple Level 2/3 model development work was initiated in 1995, and several prototype models have been completed. Once developed, these simple Level 2/3 models are linked to the simple Level 1 models to provide risk perspectives for operational events. This paper describes the methods implemented for the development of these simple Level 2/3 ASP models, and the linkage process to the existing Level 1 models.

  1. Approaches to accident analysis in recent US Department of Energy environmental impact statements

    SciTech Connect

    Mueller, C.; Folga, S.; Nabelssi, B.

    1996-12-31

    A review of accident analyses in recent US Department of Energy (DOE) Environmental Impact Statements (EISs) was conducted to evaluate the consistency among approaches and to compare these approaches with existing DOE guidance. The review considered several components of an accident analysis: the overall scope, which in turn should reflect the scope of the EIS; the spectrum of accidents considered; the methods and assumptions used to determine frequencies or frequency ranges for the accident sequences; and the assumption and technical bases for developing radiological and chemical atmospheric source terms and for calculating the consequences of airborne releases. The review also considered the range of results generated with respect to impacts on various worker and general populations. In this paper, the findings of these reviews are presented and methods recommended for improving consistency among EISs and bringing them more into line with existing DOE guidance.

  2. Analysis of the TMI-2 source range monitor during the TMI (Three Mile Island) accident

    SciTech Connect

    Wu, Horng-Yu; Baratta, A.J.; Hsiao, Ming-Yuan; Bandini, B.R.

    1987-06-01

    The source range monitor (SRM) data recorded during the first 4 hours of the Three Mile Island Unit No. 2 (TMI-2) accident following reactor shutdown were analyzed. An effort to simulate the actual SRM response was made by performing a series of neutron transport calculations. Primary emphasis was placed on simulating the changes in SRM response to various system events during the accident, so as to obtain useful information about core conditions at the various stages. Based on the known end-state reactor conditions, the major system events, and the acutal SRM readings, self-consistent estimates were made of core liquid level, void fraction in the coolant, and locations of core materials. This analysis expands the possible interpretation of the SRM data relative to core damage progression. The results appear to be consistent with other studies of the TMI-2 Accident Evaluation Program, and provide information useful for the developemnt and determination of the TMI-2 accident scenario.

  3. RBMK Safety Analysis in Accidents Initiated by Partial Ruptures of the Circulation Circuit

    SciTech Connect

    Dostov, Anatoly I.; Kramerov, Alexander Ja.

    2002-07-01

    The paper gives an analysis of the current state of the RBMK safety evaluation in accidents initiated by partial ruptures of the delivery part of the circulating loop. It appears from this analysis that applicability and uncertainty of the international code RELAP for RBMK safety analysis could not be determined up to the present. At the same time it is shown in the paper that fuel rod cladding temperature can reach the acceptability criterion in the accidents. As a result it has been concluded that bases of the next stage of the RBMK safety analysis would be creation of a code oriented to the special features of a reactor RBMK. (authors)

  4. [Fatal skiing accidents: a forensic analysis taking the example of Salzburg].

    PubMed

    Kunz, Sebastian N; Keller, Thomas; Grove, Christina; Lochner, Stefanie; Monticelli, Fabio

    2015-01-01

    The rising popularity of Alpine skiing in recent years has led to an increase of skiing accidents, some with fatal outcome. In this paper, all fatal skiing accidents from the autopsy material of the Institute of Forensic Medicine of the Paris Lodron University Salzburg were evaluated and compared with statistical data of the Alpine Police. In the wintertime of 2005/2006 until 2013/2014, 22 deadly skiing accidents were autopsied. The age of the male and female victims ranged between 12 and 71 years. The main cause of death was craniocerebral and chest trauma. A relevant blood alcohol concentration was detected in only one case. Together with trauma-biomechanical and technical experts, forensic medicine serves as a necessary clarification interface between the investigating authorities and the judiciary. Determining the cause and manner of death as well as reconstructing the accident is the main task of the forensic pathologist. The present study shows that in the county of Salzburg, only a small percentage of fatal skiing accidents is evaluated from a forensic and trauma-biomechanical point of view. Thus the possibilities of an interdisciplinary accident analysis are not always fully utilized.

  5. Risk-based Analysis of Construction Accidents in Iran During 2007-2011-Meta Analyze Study

    PubMed Central

    AMIRI, Mehran; ARDESHIR, Abdollah; FAZEL ZARANDI, Mohammad Hossein

    2014-01-01

    Abstract Background The present study aimed to investigate the characteristics of occupational accidents and frequency and severity of work related accidents in the construction industry among Iranian insured workers during the years 20072011. Methods The Iranian Social Security Organization (ISSO) accident database containing 21,864 cases between the years 2007-2011 was applied in this study. In the next step, Total Accident Rate (TRA), Total Severity Index (TSI), and Risk Factor (RF) were defined. The core of this work is devoted to analyzing the data from different perspectives such as age of workers, occupation and construction phase, day of the week, time of the day, seasonal analysis, regional considerations, type of accident, and body parts affected. Results Workers between 15-19 years old (TAR=13.4%) are almost six times more exposed to risk of accident than the average of all ages (TAR=2.51%). Laborers and structural workers (TAR=66.6%) and those working at heights (TAR=47.2%) experience more accidents than other groups of workers. Moreover, older workers over 65 years old (TSI=1.97%> average TSI=1.60%), work supervisors (TSI=12.20% >average TSI=9.09%), and night shift workers (TSI=1.89% >average TSI=1.47%) are more prone to severe accidents. Conclusion It is recommended that laborers, young workers, weekend and night shift workers be supervised more carefully in the workplace. Use of Personal Protective Equipment (PPE) should be compulsory in working environments, and special attention should be undertaken to people working outdoors and at heights. It is also suggested that policymakers pay more attention to the improvement of safety conditions in deprived and cold western regions. PMID:26005662

  6. 3W Analysis of FY 78 Army Aircraft Accidents.

    DTIC Science & Technology

    1979-05-01

    Callen, J. R., "Pilot Error Accidents Aren’t All Pilot," United States Army Agency for Aviation Safety, May 1975. 25 ~ ~ - APPENDICES 27 til - -1P I If 2...LJSASC-TR-79- ML DIS RII3UMUN STATZLIA USASC TECHNICAL REPORT Approved fox public releaqw TR 79.3 Ana Iyss Of FY78 704Acidents. A.L:fM ;what happened...construed as an official Department of the Army position, policy , or decision, unless so designated by other official authority. The findings of this

  7. [Comparative analysis of the radionuclide composition in fallout after the Chernobyl and the Fukushima accidents].

    PubMed

    Kotenko, K V; Shinkarev, S M; Abramov, Iu V; Granovskaia, E O; Iatsenko, V N; Gavrilin, Iu I; Margulis, U Ia; Garetskaia, O S; Imanaka, T; Khoshi, M

    2012-01-01

    The nuclear accident occurred at Fukushima Dai-ichi Nuclear Power Plant (NPP) (March 11, 2011) similarly to the accident at the Chernobyl NPP (April 26, 1986) is related to the level 7 of the INES. It is of interest to make an analysis of the radionuclide composition of the fallout following the both accidents. The results of the spectrometric measurements were used in that comparative analysis. Two areas following the Chernobyl accident were considered: (1) the near zone of the fallout - the Belarusian part of the central spot extended up to 60 km around the Chernobyl NPS and (2) the far zone of the fallout--the "Gomel-Mogilev" spot centered 200 km to the north-northeast of the damaged reactor. In the case of Fukushima accident the near zone up to about 60 km considered. The comparative analysis has been done with respect to refractory radionuclides (95Zr, 95Nb, 141Ce, 144Ce), as well as to the intermediate and volatile radionuclides 103Ru, 106Ru, 131I, 134Cs, 137Cs, 140La, 140Ba and the results of such a comparison have been discussed. With respect to exposure to the public the most important radionuclides are 131I and 137Cs. For the both accidents the ratios of 131I/137Cs in the considered soil samples are in the similar ranges: (3-50) for the Chernobyl samples and (5-70) for the Fukushima samples. Similarly to the Chernobyl accident a clear tendency that the ratio of 131I/137Cs in the fallout decreases with the increase of the ground deposition density of 137Cs within the trace related to a radioactive cloud has been identified for the Fukushima accident. It looks like this is a universal tendency for the ratio of 131I/137Cs versus the 137Cs ground deposition density in the fallout along the trace of a radioactive cloud as a result of a heavy accident at the NPP with radionuclides releases into the environment. This tendency is important for an objective reconstruction of 131I fallout based on the results of 137Cs measurements of soil samples carried out at

  8. The role of mitochondrial proteomic analysis in radiological accidents and terrorism.

    PubMed

    Maguire, David; Zhang, Bingrong; Zhang, Amy; Zhang, Lurong; Okunieff, Paul

    2013-01-01

    In the wake of the 9/11 terrorist attacks and the recent Level 7 nuclear event at the Fukushima Daiichi plant, there has been heightened awareness of the possibility of radiological terrorism and accidents and the need for techniques to estimate radiation levels after such events. A number of approaches to monitoring radiation using biological markers have been published, including physical techniques, cytogenetic approaches, and direct, DNA-analysis approaches. Each approach has the potential to provide information that may be applied to the triage of an exposed population, but problems with development and application of devices or lengthy analyses limit their potential for widespread application. We present a post-irradiation observation with the potential for development into a rapid point-of-care device. Using simple mitochondrial proteomic analysis, we investigated irradiated and nonirradiated murine mitochondria and identified a protein mobility shift occurring at 2-3 Gy. We discuss the implications of this finding both in terms of possible mechanisms and potential applications in bio-radiation monitoring.

  9. Analysis of occupational accidents: prevention through the use of additional technical safety measures for machinery

    PubMed Central

    Dźwiarek, Marek; Latała, Agata

    2016-01-01

    This article presents an analysis of results of 1035 serious and 341 minor accidents recorded by Poland's National Labour Inspectorate (PIP) in 2005–2011, in view of their prevention by means of additional safety measures applied by machinery users. Since the analysis aimed at formulating principles for the application of technical safety measures, the analysed accidents should bear additional attributes: the type of machine operation, technical safety measures and the type of events causing injuries. The analysis proved that the executed tasks and injury-causing events were closely connected and there was a relation between casualty events and technical safety measures. In the case of tasks consisting of manual feeding and collecting materials, the injuries usually occur because of the rotating motion of tools or crushing due to a closing motion. Numerous accidents also happened in the course of supporting actions, like removing pollutants, correcting material position, cleaning, etc. PMID:26652689

  10. [Model of Analysis and Prevention of Accidents - MAPA: tool for operational health surveillance].

    PubMed

    de Almeida, Ildeberto Muniz; Vilela, Rodolfo Andrade de Gouveia; da Silva, Alessandro José Nunes; Beltran, Sandra Lorena

    2014-12-01

    The analysis of work-related accidents is important for accident surveillance and prevention. Current methods of analysis seek to overcome reductionist views that see these occurrences as simple events explained by operator error. The objective of this paper is to analyze the Model of Analysis and Prevention of Accidents (MAPA) and its use in monitoring interventions, duly highlighting aspects experienced in the use of the tool. The descriptive analytical method was used, introducing the steps of the model. To illustrate contributions and or difficulties, cases where the tool was used in the context of service were selected. MAPA integrates theoretical approaches that have already been tried in studies of accidents by providing useful conceptual support from the data collection stage until conclusion and intervention stages. Besides revealing weaknesses of the traditional approach, it helps identify organizational determinants, such as management failings, system design and safety management involved in the accident. The main challenges lie in the grasp of concepts by users, in exploring organizational aspects upstream in the chain of decisions or at higher levels of the hierarchy, as well as the intervention to change the determinants of these events.

  11. The failure analysis of composite material flight helmets as an aid in aircraft accident investigation.

    PubMed

    Caine, Y G; Bain-Ungerson, O; Schochat, I; Marom, G

    1991-06-01

    Understanding why a flying helmet fails to maintain its integrity during an accident can contribute to an understanding of the mechanism of injury and even of the accident itself. We performed a post-accident evaluation of failure modes in glass and aramid fibre-reinforced composite helmets. Optical and microscopic (SEM) techniques were employed to identify specific fracture mechanisms. They were correlated with the failure mode. Stress and energy levels were estimated from the damage extent. Damage could be resolved into distinct impact, flexure and compression components. Delamination was identified as a specific mode, dependent upon the matrix material and bonding between the layers. From the energy dissipated in specific fracture mechanisms we calculated the minimum total energy imparted to the helmet-head combination and the major injury vector (MIV) direction and magnitude. The level of protection provided by the helmet can also be estimated.

  12. MELCOR code analysis of a severe accident LOCA at Peach Bottom Plant

    SciTech Connect

    Carbajo, J.J. )

    1993-01-01

    A design-basis loss-of-coolant accident (LOCA) concurrent with complete loss of the emergency core cooling systems (ECCSs) has been analyzed for the Peach Bottom atomic station unit 2 using the MELCOR code, version 1.8.1. The purpose of this analysis is to calculate best-estimate times for the important events of this accident sequence and best-estimate source terms. Calculated pressures and temperatures at the beginning of the transient have been compared to results from the Peach Bottom final safety analysis report (FSAR). MELCOR-calculated source terms have been compared to source terms reported in the NUREG-1465 draft.

  13. Risk of Occupational Accidents in Workers with Obstructive Sleep Apnea: Systematic Review and Meta-analysis

    PubMed Central

    Garbarino, Sergio; Guglielmi, Ottavia; Sanna, Antonio; Mancardi, Gian Luigi; Magnavita, Nicola

    2016-01-01

    Study Objectives: Obstructive sleep apnea (OSA) is the single most important preventable medical cause of excessive daytime sleepiness (EDS) and driving accidents. OSA may also adversely affect work performance through a decrease in productivity, and an increase in the injury rate. Nevertheless, no systematic review and meta-analysis of the relationship between OSA and work accidents has been performed thus far. Methods: PubMed, PsycInfo, Scopus, Web of Science, and Cochrane Library were searched. Out of an initial list of 1,099 papers, 10 studies (12,553 participants) were eligible for our review, and 7 of them were included in the meta-analysis. The overall effects were measured by odds ratios (OR) and 95% confidence intervals (CI). An assessment was made of the methodological quality of the studies. Moderator analysis and funnel plot analysis were used to explore the sources of between-study heterogeneity. Results: Compared to controls, the odds of work accident was found to be nearly double in workers with OSA (OR = 2.18; 95% CI = 1.53–3.10). Occupational driving was associated with a higher effect size. Conclusions: OSA is an underdiagnosed nonoccupational disease that has a strong adverse effect on work accidents. The nearly twofold increased odds of work accidents in subjects with OSA calls for workplace screening in selected safety-sensitive occupations. Commentary: A commentary on this article appears in this issue on page 1171. Citation: Garbarino S, Guglielmi O, Sanna A, Mancardi GL, Magnavita N. Risk of occupational accidents in workers with obstructive sleep apnea: systematic review and meta-analysis. SLEEP 2016;39(6):1211–1218. PMID:26951401

  14. Accident analysis of railway transportation of low-level radioactive and hazardous chemical wastes: Application of the /open quotes/Maximum Credible Accident/close quotes/ concept

    SciTech Connect

    Ricci, E.; McLean, R.B.

    1988-09-01

    The maximum credible accident (MCA) approach to accident analysis places an upper bound on the potential adverse effects of a proposed action by using conservative but simplifying assumptions. It is often used when data are lacking to support a more realistic scenario or when MCA calculations result in acceptable consequences. The MCA approach can also be combined with realistic scenarios to assess potential adverse effects. This report presents a guide for the preparation of transportation accident analyses based on the use of the MCA concept. Rail transportation of contaminated wastes is used as an example. The example is the analysis of the environmental impact of the potential derailment of a train transporting a large shipment of wastes. The shipment is assumed to be contaminated with polychlorinated biphenyls and low-level radioactivities of uranium and technetium. The train is assumed to plunge into a river used as a source of drinking water. The conclusions from the example accident analysis are based on the calculation of the number of foreseeable premature cancer deaths the might result as a consequence of this accident. These calculations are presented, and the reference material forming the basis for all assumptions and calculations is also provided.

  15. RELAP5 Application to Accident Analysis of the NIST Research Reactor

    SciTech Connect

    Baek, J.; Cuadra Gascon, A.; Cheng, L.Y.; Diamond, D.

    2012-03-18

    Detailed safety analyses have been performed for the 20 MW D{sub 2}O moderated research reactor (NBSR) at the National Institute of Standards and Technology (NIST). The time-dependent analysis of the primary system is determined with a RELAP5 transient analysis model that includes the reactor vessel, the pump, heat exchanger, fuel element geometry, and flow channels for both the six inner and twenty-four outer fuel elements. A post-processing of the simulation results has been conducted to evaluate minimum critical heat flux ratio (CHFR) using the Sudo-Kaminaga correlation. Evaluations are performed for the following accidents: (1) the control rod withdrawal startup accident and (2) the maximum reactivity insertion accident. In both cases the RELAP5 results indicate that there is adequate margin to CHF and no damage to the fuel will occur because of sufficient coolant flow through the fuel channels and the negative scram reactivity insertion.

  16. Radioactivity analysis following the Fukushima Dai-ichi nuclear accident.

    PubMed

    Tuo, Fei; Xu, Cuihua; Zhang, Jing; Zhou, Qiang; Li, Wenhong; Zhao, Li; Zhang, Qing; Zhang, Jianfeng; Su, Xu

    2013-08-01

    A total of 118 samples were analyzed using HPGe γ-spectrometry. (131)I, (134)Cs, (137)Cs and (136)Cs were detected in aerosol air samples that were collected 22 days after the accident with values of 1720 µBq m(-)³, 247 µBq m(-)³, 289 µBq m(-)³ and 23 µBq m(-)³, respectively. (131)I was detected in rainwater and soil samples and was also measurable in vegetables collected between April 2 and 13, 2011, with values ranging from 0.55 Bq kg(-1) to 2.68 Bq kg(-1). No (131)I was detected in milk, drinking water, seawater or marine biota samples.

  17. OSSE spectral analysis techniques

    NASA Technical Reports Server (NTRS)

    Purcell, W. R.; Brown, K. M.; Grabelsky, D. A.; Johnson, W. N.; Jung, G. V.; Kinzer, R. L.; Kroeger, R. A.; Kurfess, J. D.; Matz, S. M.; Strickman, M. S.

    1992-01-01

    Analysis of the spectra from the Oriented Scintillation Spectrometer Experiment (OSSE) is complicated because of the typically low signal to noise (approx. 0.1 percent) and the large background variability. The OSSE instrument was designed to address these difficulties by periodically offset-pointing the detectors from the source to perform background measurements. These background measurements are used to estimate the background during each of the source observations. The resulting background-subtracted spectra can then be accumulated and fitted for spectral lines and/or continua. Data selection based on various environmental parameters can be performed at various stages during the analysis procedure. In order to achieve the instrument's statistical sensitivity, however, it will be necessary for investigators to develop a detailed understanding of the instrument operation, data collection, and the background spectrum and its variability. A brief description of the major steps in the OSSE spectral analysis process is described, including a discussion of the OSSE background spectrum and examples of several observational strategies.

  18. Space Shuttle Columbia Post-Accident Analysis and Investigation

    NASA Technical Reports Server (NTRS)

    McDanels, Steven J.

    2006-01-01

    Although the loss of the Space Shuttle Columbia and its crew was tragic, the circumstances offered a unique opportunity to examine a multitude of components which had experienced one of the harshest environments ever encountered by engineered materials: a break up at a velocity in excess of Mach 18 and an altitude exceeding 200,000 feet (63 KM), resulting in a debris field 645 miles/l,038 KM long and 10 miles/16 KM wide. Various analytical tools were employed to ascertain the sequence of events leading to the disintegration of the Orbiter and to characterize the features of the debris. The testing and analyses all indicated that a breach in a left wing reinforced carbon/carbon composite leading edge panel was the access point for hot gasses generated during re-entry to penetrate the structure of the vehicle and compromise the integrity of the materials and components in that area of the Shuttle. The analytical and elemental testing utilized such techniques as X-Ray Diffraction (XRD), Energy Dispersive X-Ray (EDX) dot mapping, Electron Micro Probe Analysis (EMPA), and X-Ray Photoelectron Spectroscopy (XPS) to characterize the deposition of intermetallics adjacent to the suspected location of the plasma breach in the leading edge of the left wing, Fig. 1.

  19. Analysis of fission product release behavior during the TMI-2 accident

    SciTech Connect

    Petti, D. A.; Adams, J. P.; Anderson, J. L.; Hobbins, R. R.

    1987-01-01

    An analysis of fission product release during the Three Mile Island Unit 2 (TMI-2) accident has been initiated to provide an understanding of fission product behavior that is consistent with both the best estimate accident scenario and fission product results from the ongoing sample acquisition and examination efforts. ''First principles'' fission product release models are used to describe release from intact, disrupted, and molten fuel. Conclusions relating to fission product release, transport, and chemical form are drawn. 35 refs., 12 figs., 7 tabs.

  20. NASA standard: Trend analysis techniques

    NASA Technical Reports Server (NTRS)

    1990-01-01

    Descriptive and analytical techniques for NASA trend analysis applications are presented in this standard. Trend analysis is applicable in all organizational elements of NASA connected with, or supporting, developmental/operational programs. This document should be consulted for any data analysis activity requiring the identification or interpretation of trends. Trend analysis is neither a precise term nor a circumscribed methodology: it generally connotes quantitative analysis of time-series data. For NASA activities, the appropriate and applicable techniques include descriptive and graphical statistics, and the fitting or modeling of data by linear, quadratic, and exponential models. Usually, but not always, the data is time-series in nature. Concepts such as autocorrelation and techniques such as Box-Jenkins time-series analysis would only rarely apply and are not included in this document. The basic ideas needed for qualitative and quantitative assessment of trends along with relevant examples are presented.

  1. Calculation and analysis of the cause of the collapse accident to a bridge

    NASA Astrophysics Data System (ADS)

    Zhao, Zhanshan; Wu, Longfei; Zhang, Yijing

    2017-03-01

    The causes of the collapse accident of the steel tube scaffold are summarized and analyzed. Combined with practical engineering, the cause of the bridge collapse was analyzed from construction management, raw materials, fastener mechanics performance and stability calculation, which provides a reference for practical engineering analysis, and puts forward related suggestions.

  2. Preliminary Analysis of Aircraft Loss of Control Accidents: Worst Case Precursor Combinations and Temporal Sequencing

    NASA Technical Reports Server (NTRS)

    Belcastro, Christine M.; Groff, Loren; Newman, Richard L.; Foster, John V.; Crider, Dennis H.; Klyde, David H.; Huston, A. McCall

    2014-01-01

    Aircraft loss of control (LOC) is a leading cause of fatal accidents across all transport airplane and operational classes, and can result from a wide spectrum of hazards, often occurring in combination. Technologies developed for LOC prevention and recovery must therefore be effective under a wide variety of conditions and uncertainties, including multiple hazards, and their validation must provide a means of assessing system effectiveness and coverage of these hazards. This requires the definition of a comprehensive set of LOC test scenarios based on accident and incident data as well as future risks. This paper defines a comprehensive set of accidents and incidents over a recent 15 year period, and presents preliminary analysis results to identify worst-case combinations of causal and contributing factors (i.e., accident precursors) and how they sequence in time. Such analyses can provide insight in developing effective solutions for LOC, and form the basis for developing test scenarios that can be used in evaluating them. Preliminary findings based on the results of this paper indicate that system failures or malfunctions, crew actions or inactions, vehicle impairment conditions, and vehicle upsets contributed the most to accidents and fatalities, followed by inclement weather or atmospheric disturbances and poor visibility. Follow-on research will include finalizing the analysis through a team consensus process, defining future risks, and developing a comprehensive set of test scenarios with correlation to the accidents, incidents, and future risks. Since enhanced engineering simulations are required for batch and piloted evaluations under realistic LOC precursor conditions, these test scenarios can also serve as a high-level requirement for defining the engineering simulation enhancements needed for generating them.

  3. Sensitivity analysis of an accident prediction model by the fractional factorial method.

    PubMed

    Akgüngör, Ali P; Yildiz, Osman

    2007-01-01

    Sensitivity analysis of a model can help us determine relative effects of model parameters on model results. In this study, the sensitivity of the accident prediction model proposed by Zegeer et al. [Zegeer, C.V., Reinfurt, D., Hummer, J., Herf, L., Hunter, W., 1987. Safety Effect of Cross-section Design for Two-lane Roads, vols. 1-2. Report FHWA-RD-87/008 and 009 Federal Highway Administration, Department of Transportation, USA] to its parameters was investigated by the fractional factorial analysis method. The reason for selecting this particular model is that it incorporates both traffic and road geometry parameters besides terrain characteristics. The evaluation of sensitivity analysis indicated that average daily traffic (ADT), lane width (W), width of paved shoulder (PA), median (H) and their interactions (i.e., ADT-W, ADT-PA and ADT-H) have significant effects on number of accidents. Based on the absolute value of parameter effects at the three- and two-standard deviation thresholds ADT was found to be of primary importance, while the remaining identified parameters seemed to be of secondary importance. This agrees with the fact that ADT is among the most effective parameters to determine road geometry and therefore, it is directly related to number of accidents. Overall, the fractional factorial method was found to be an efficient tool to examine the relative importance of the selected accident prediction model parameters.

  4. Analysis of ex-core neutron detector response during a loss-of-coolant accident

    SciTech Connect

    Baratta, A.J.; Jester, W.A. ); Gundy, L.M. ); Imel, G.R. )

    1991-06-01

    In this paper the experimental response of ex-core neutron detectors during both actual and simulated loss-of-coolant accidents (LOCAs) at a pressurized water reactor are analyzed to determine their cause. Various analytical techniques are used to reproduce the ex-core detector response during large-break LOCAs. These techniques include both discrete ordinates transport and point kernel calculations. The experiments analyzed include large-break LOCA experiments at the Loss of Fluid Test Facility and from the Three Mile Island accident. The results show that an adiabatic method is sufficiently accurate to reproduce the detector response. This response can be explained in terms of the combined effects of changes in shielding and multiplication that occur in a core during a LOCA.

  5. A comparison of two micro-beam X-ray emission techniques for actinide elemental distribution in microscopic particles originating from the hydrogen bombs involved in the Palomares (Spain) and Thule (Greenland) accidents

    NASA Astrophysics Data System (ADS)

    Jimenez-Ramos, M. C.; Eriksson, M.; García-López, J.; Ranebo, Y.; García-Tenorio, R.; Betti, M.; Holm, E.

    2010-09-01

    In order to validate and to gain confidence in two micro-beam techniques: particle induced X-ray emission with nuclear microprobe technique (μ-PIXE) and synchrotron radiation induced X-ray fluorescence in a confocal alignment (confocal SR μ-XRF) for characterization of microscopic particles containing actinide elements (mixed plutonium and uranium) a comparative study has been performed. Inter-comparison of the two techniques is essential as the X-ray production cross-sections for U and Pu are different for protons and photons and not well defined in the open literature, especially for Pu. The particles studied consisted of nuclear weapons material, and originate either in the so called Palomares accident in Spain, 1966 or in the Thule accident in Greenland, 1968. In the determination of the average Pu/U mass ratios (not corrected by self-absorption) in the analysed microscopic particles the results from both techniques show a very good agreement. In addition, the suitability of both techniques for the analysis with good resolution (down to a few μm) of the Pu/U distribution within the particles has been proved. The set of results obtained through both techniques has allowed gaining important information concerning the characterization of the remaining fissile material in the areas affected by the aircraft accidents. This type of information is essential for long-term impact assessments of contaminated sites.

  6. Compendium on Risk Analysis Techniques

    DTIC Science & Technology

    The evolution of risk analysis in the materiel acquisition process is traced from the Secretary Packard memorandum to current AMC guidance. Risk ... analysis is defined and many of the existing techniques are described in light of this definition and their specific role in program management and

  7. SAMPSON Parallel Computation for Sensitivity Analysis of TEPCO's Fukushima Daiichi Nuclear Power Plant Accident

    NASA Astrophysics Data System (ADS)

    Pellegrini, M.; Bautista Gomez, L.; Maruyama, N.; Naitoh, M.; Matsuoka, S.; Cappello, F.

    2014-06-01

    On March 11th 2011 a high magnitude earthquake and consequent tsunami struck the east coast of Japan, resulting in a nuclear accident unprecedented in time and extents. After scram started at all power stations affected by the earthquake, diesel generators began operation as designed until tsunami waves reached the power plants located on the east coast. This had a catastrophic impact on the availability of plant safety systems at TEPCO's Fukushima Daiichi, leading to the condition of station black-out from unit 1 to 3. In this article the accident scenario is studied with the SAMPSON code. SAMPSON is a severe accident computer code composed of hierarchical modules to account for the diverse physics involved in the various phases of the accident evolution. A preliminary parallelization analysis of the code was performed using state-of-the-art tools and we demonstrate how this work can be beneficial to the nuclear safety analysis. This paper shows that inter-module parallelization can reduce the time to solution by more than 20%. Furthermore, the parallel code was applied to a sensitivity study for the alternative water injection into TEPCO's Fukushima Daiichi unit 3. Results show that the core melting progression is extremely sensitive to the amount and timing of water injection, resulting in a high probability of partial core melting for unit 3.

  8. The Role of Materials Degradation and Analysis in the Space Shuttle Columbia Accident Investigation

    NASA Technical Reports Server (NTRS)

    McDanels, Steven J.

    2006-01-01

    The efforts following the loss of the Space Shuttle Columbia included debris recovery, reconstruction, and analysis. The debris was subjected to myriad quantitative and semiquantitative chemical analysis techniques, ranging from examination via the scanning electron microscope (SEM) with energy dispersive spectrometer (EDS) to X-Ray diffraction (XRD) and electron probe micro-analysis (EPMA). The results from the work with the debris helped the investigators determine the location where a breach likely occurred in the leading edge of the left wing during lift off of the Orbiter from the Kennedy Space Center. Likewise, the information evidenced by the debris was also crucial in ascertaining the path of impinging plasma flow once it had breached the wing. After the Columbia Accident Investigation Board (CAIB) issued its findings, the major portion of the investigation was concluded. However, additional work remained to be done on many pieces of debris from portions of the Orbiter which were not directly related to the initial impact during ascent. This subsequent work was not only performed in the laboratory, but was also performed with portable equipment, including examination via portable X-Ray fluorescence (XRF) and Fourier transform infrared spectroscopy (FTIR). Likewise, acetate and silicon-rubber replicas of various fracture surfaces were obtained for later macroscopic and fractographic examination. This paper will detail the efforts and findings from the initial investigation, as well as present results obtained by the later examination and analysis of debris from the Orbiter including its windows, bulkhead structures, and other components which had not been examined during the primary investigation.

  9. Quantitative Techniques in Volumetric Analysis

    NASA Astrophysics Data System (ADS)

    Zimmerman, John; Jacobsen, Jerrold J.

    1996-12-01

    Quantitative Techniques in Volumetric Analysis is a visual library of techniques used in making volumetric measurements. This 40-minute VHS videotape is designed as a resource for introducing students to proper volumetric methods and procedures. The entire tape, or relevant segments of the tape, can also be used to review procedures used in subsequent experiments that rely on the traditional art of quantitative analysis laboratory practice. The techniques included are: Quantitative transfer of a solid with a weighing spoon Quantitative transfer of a solid with a finger held weighing bottle Quantitative transfer of a solid with a paper strap held bottle Quantitative transfer of a solid with a spatula Examples of common quantitative weighing errors Quantitative transfer of a solid from dish to beaker to volumetric flask Quantitative transfer of a solid from dish to volumetric flask Volumetric transfer pipet A complete acid-base titration Hand technique variations The conventional view of contemporary quantitative chemical measurement tends to focus on instrumental systems, computers, and robotics. In this view, the analyst is relegated to placing standards and samples on a tray. A robotic arm delivers a sample to the analysis center, while a computer controls the analysis conditions and records the results. In spite of this, it is rare to find an analysis process that does not rely on some aspect of more traditional quantitative analysis techniques, such as careful dilution to the mark of a volumetric flask. Figure 2. Transfer of a solid with a spatula. Clearly, errors in a classical step will affect the quality of the final analysis. Because of this, it is still important for students to master the key elements of the traditional art of quantitative chemical analysis laboratory practice. Some aspects of chemical analysis, like careful rinsing to insure quantitative transfer, are often an automated part of an instrumental process that must be understood by the

  10. Analysis of the FeCrAl Accident Tolerant Fuel Concept Benefits during BWR Station Blackout Accidents

    SciTech Connect

    Robb, Kevin R

    2015-01-01

    Iron-chromium-aluminum (FeCrAl) alloys are being considered for fuel concepts with enhanced accident tolerance. FeCrAl alloys have very slow oxidation kinetics and good strength at high temperatures. FeCrAl could be used for fuel cladding in light water reactors and/or as channel box material in boiling water reactors (BWRs). To estimate the potential safety gains afforded by the FeCrAl concept, the MELCOR code was used to analyze a range of postulated station blackout severe accident scenarios in a BWR/4 reactor employing FeCrAl. The simulations utilize the most recently known thermophysical properties and oxidation kinetics for FeCrAl. Overall, when compared to the traditional Zircaloy-based cladding and channel box, the FeCrAl concept provides a few extra hours of time for operators to take mitigating actions and/or for evacuations to take place. A coolable core geometry is retained longer, enhancing the ability to stabilize an accident. Finally, due to the slower oxidation kinetics, substantially less hydrogen is generated, and the generation is delayed in time. This decreases the amount of non-condensable gases in containment and the potential for deflagrations to inhibit the accident response.

  11. [Analysis of radiation-hygienic and medical consequences of the Chernobyl accident].

    PubMed

    Onishchenko, G G

    2013-01-01

    Since the day of "the Chernobyl accident" in 1986 more than 25 years have been past. Radioactively contaminated areas 14 subjects of the Russian Federation with a total area of more than 50 thousand km2, where 1.5 million people now reside were exposed to radioactive contamination. Currently, a system of comprehensive evaluation of radiation doses of the population affected by the "Chernobyl accidents", including 11 guidance documents has been created. There are methodically provided works on the assessment of average annual, accumulated and predicted radiation doses of population and its critical groups, as well as doses to the thyroid gland The relevance of the analysis of the consequences of the "Chernobyl accident" is demonstrated by the events in Japan, at nuclear power Fukusima-1. In 2011 - 20/2 there were carried out comprehensive maritime expeditions under the auspices of the Russian Geographical Society with the participation of relevant ministries and agencies, leading academic institutions in Russia. In 2012, work was carried out on radiation protection of the population from the potential transboundary impact of the accident at the Japanese nuclear power plant Fukushima-l. The results provide a basis for the favorable outlook for the radiation environment in our Far East and the Pacific coast of Russia.

  12. Retrospective reconstruction of Ioidne-131 distribution at the Fukushima Daiichi Nuclear Power Plant accident by analysis of Ioidne-129

    NASA Astrophysics Data System (ADS)

    Matsuzaki, Hiroyuki; Muramatsu, Yasuyuki; Toyama, Chiaki; Ohno, Takeshi; Kusuno, Haruka; Miyake, Yasuto; Honda, Maki

    2014-05-01

    Among various radioactive nuclides emitted from the Fukushima Daiichi Nuclear Power Plant (FDNPP) accident, Iodine-131 displayed high radioactivity just after the accident. Moreover if taken into human body, Iodine-131 concentrates in the thyroid and may cause the thyroid cancer. The recognition about the risk of Iodine-131 dose originated from the experience of the Chernobyl accident based on the epidemiological study [1]. It is thus important to investigate the detailed deposition distribution of I-131 to evaluate the radiation dose due to I-131 and watch the influence on the human health. However I-131 decays so rapidly (half life = 8.02 d) that it cannot be detected several months after the accident. At the recognition of the risk of I-131 on the Chernobyl occasion, it had gone several years after the accident. The reconstruction of I-131 distribution from Cs-137 distribution was not successful because the behavior of iodine and cesium was different because they have different chemical properties. Long lived radioactive isotope I-129 (half life = 1.57E+7 yr,), which is also a fission product as well as I-131, is ideal proxy for I-131 because they are chemically identical. Several studies had tried to quantify I-129 in 1990's but the analytical technique, especially AMS (Accelerator Mass Spectrometry), had not been developed well and available AMS facility was limited. Moreover because of the lack of enough data on I-131 just after the accident, the isotopic ratio I-129/I-131 of the Chernobyl derived iodine could not been estimated precisely [2]. Calculated estimation of the isotopic ratio showed scattered results. On the other hand, at the FDNPP accident detailed I-131 distribution is going to be successfully reconstructed by the systematical I-129 measurements by our group. We measured soil samples selected from a series of soil collection taken from every 2 km (or 5km, in the distant area) meshed region around FDNPP conducted by the Japanese Ministry of

  13. NASA standard: Trend analysis techniques

    NASA Technical Reports Server (NTRS)

    1988-01-01

    This Standard presents descriptive and analytical techniques for NASA trend analysis applications. Trend analysis is applicable in all organizational elements of NASA connected with, or supporting, developmental/operational programs. Use of this Standard is not mandatory; however, it should be consulted for any data analysis activity requiring the identification or interpretation of trends. Trend Analysis is neither a precise term nor a circumscribed methodology, but rather connotes, generally, quantitative analysis of time-series data. For NASA activities, the appropriate and applicable techniques include descriptive and graphical statistics, and the fitting or modeling of data by linear, quadratic, and exponential models. Usually, but not always, the data is time-series in nature. Concepts such as autocorrelation and techniques such as Box-Jenkins time-series analysis would only rarely apply and are not included in this Standard. The document presents the basic ideas needed for qualitative and quantitative assessment of trends, together with relevant examples. A list of references provides additional sources of information.

  14. Coupled thermal analysis applied to the study of the rod ejection accident

    SciTech Connect

    Gonnet, M.

    2012-07-01

    An advanced methodology for the assessment of fuel-rod thermal margins under RIA conditions has been developed by AREVA NP SAS. With the emergence of RIA analytical criteria, the study of the Rod Ejection Accident (REA) would normally require the analysis of each fuel rod, slice by slice, over the whole core. Up to now the strategy used to overcome this difficulty has been to perform separate analyses of sampled fuel pins with conservative hypotheses for thermal properties and boundary conditions. In the advanced methodology, the evaluation model for the Rod Ejection Accident (REA) integrates the node average fuel and coolant properties calculation for neutron feedback purpose as well as the peak fuel and coolant time-dependent properties for criteria checking. The calculation grid for peak fuel and coolant properties can be specified from the assembly pitch down to the cell pitch. The comparative analysis of methodologies shows that coupled methodology allows reducing excessive conservatism of the uncoupled approach. (authors)

  15. An association between dietary habits and traffic accidents in patients with chronic liver disease: A data-mining analysis

    PubMed Central

    KAWAGUCHI, TAKUMI; SUETSUGU, TAKURO; OGATA, SHYOU; IMANAGA, MINAMI; ISHII, KUMIKO; ESAKI, NAO; SUGIMOTO, MASAKO; OTSUYAMA, JYURI; NAGAMATSU, AYU; TANIGUCHI, EITARO; ITOU, MINORU; ORIISHI, TETSUHARU; IWASAKI, SHOKO; MIURA, HIROKO; TORIMURA, TAKUJI

    2016-01-01

    The incidence of traffic accidents in patients with chronic liver disease (CLD) is high in the USA. However, the characteristics of patients, including dietary habits, differ between Japan and the USA. The present study investigated the incidence of traffic accidents in CLD patients and the clinical profiles associated with traffic accidents in Japan using a data-mining analysis. A cross-sectional study was performed and 256 subjects [148 CLD patients (CLD group) and 106 patients with other digestive diseases (disease control group)] were enrolled; 2 patients were excluded. The incidence of traffic accidents was compared between the two groups. Independent factors for traffic accidents were analyzed using logistic regression and decision-tree analyses. The incidence of traffic accidents did not differ between the CLD and disease control groups (8.8 vs. 11.3%). The results of the logistic regression analysis showed that yoghurt consumption was the only independent risk factor for traffic accidents (odds ratio, 0.37; 95% confidence interval, 0.16–0.85; P=0.0197). Similarly, the results of the decision-tree analysis showed that yoghurt consumption was the initial divergence variable. In patients who consumed yoghurt habitually, the incidence of traffic accidents was 6.6%, while that in patients who did not consume yoghurt was 16.0%. CLD was not identified as an independent factor in the logistic regression and decision-tree analyses. In conclusion, the difference in the incidence of traffic accidents in Japan between the CLD and disease control groups was insignificant. Furthermore, yoghurt consumption was an independent negative risk factor for traffic accidents in patients with digestive diseases, including CLD. PMID:27123257

  16. An association between dietary habits and traffic accidents in patients with chronic liver disease: A data-mining analysis.

    PubMed

    Kawaguchi, Takumi; Suetsugu, Takuro; Ogata, Shyou; Imanaga, Minami; Ishii, Kumiko; Esaki, Nao; Sugimoto, Masako; Otsuyama, Jyuri; Nagamatsu, Ayu; Taniguchi, Eitaro; Itou, Minoru; Oriishi, Tetsuharu; Iwasaki, Shoko; Miura, Hiroko; Torimura, Takuji

    2016-05-01

    The incidence of traffic accidents in patients with chronic liver disease (CLD) is high in the USA. However, the characteristics of patients, including dietary habits, differ between Japan and the USA. The present study investigated the incidence of traffic accidents in CLD patients and the clinical profiles associated with traffic accidents in Japan using a data-mining analysis. A cross-sectional study was performed and 256 subjects [148 CLD patients (CLD group) and 106 patients with other digestive diseases (disease control group)] were enrolled; 2 patients were excluded. The incidence of traffic accidents was compared between the two groups. Independent factors for traffic accidents were analyzed using logistic regression and decision-tree analyses. The incidence of traffic accidents did not differ between the CLD and disease control groups (8.8 vs. 11.3%). The results of the logistic regression analysis showed that yoghurt consumption was the only independent risk factor for traffic accidents (odds ratio, 0.37; 95% confidence interval, 0.16-0.85; P=0.0197). Similarly, the results of the decision-tree analysis showed that yoghurt consumption was the initial divergence variable. In patients who consumed yoghurt habitually, the incidence of traffic accidents was 6.6%, while that in patients who did not consume yoghurt was 16.0%. CLD was not identified as an independent factor in the logistic regression and decision-tree analyses. In conclusion, the difference in the incidence of traffic accidents in Japan between the CLD and disease control groups was insignificant. Furthermore, yoghurt consumption was an independent negative risk factor for traffic accidents in patients with digestive diseases, including CLD.

  17. Human and organisational factors in maritime accidents: analysis of collisions at sea using the HFACS.

    PubMed

    Chauvin, Christine; Lardjane, Salim; Morel, Gaël; Clostermann, Jean-Pierre; Langard, Benoît

    2013-10-01

    Over the last decade, the shipping industry has implemented a number of measures aimed at improving its safety level (such as new regulations or new forms of team training). Despite this evolution, shipping accidents, and particularly collisions, remain a major concern. This paper presents a modified version of the Human Factors Analysis and Classification System, which has been adapted to the maritime context and used to analyse human and organisational factors in collisions reported by the Marine Accident and Investigation Branch (UK) and the Transportation Safety Board (Canada). The analysis shows that most collisions are due to decision errors. At the precondition level, it highlights the importance of the following factors: poor visibility and misuse of instruments (environmental factors), loss of situation awareness or deficit of attention (conditions of operators), deficits in inter-ship communications or Bridge Resource Management (personnel factors). At the leadership level, the analysis reveals the frequent planning of inappropriate operations and non-compliance with the Safety Management System (SMS). The Multiple Accident Analysis provides an important finding concerning three classes of accidents. Inter-ship communications problems and Bridge Resource Management deficiencies are closely linked to collisions occurring in restricted waters and involving pilot-carrying vessels. Another class of collisions is associated with situations of poor visibility, in open sea, and shows deficiencies at every level of the socio-technical system (technical environment, condition of operators, leadership level, and organisational level). The third class is characterised by non-compliance with the SMS. This study shows the importance of Bridge Resource Management for situations of navigation with a pilot on board in restricted waters. It also points out the necessity to investigate, for situations of navigation in open sea, the masters' decisions in critical conditions

  18. Human Error and Commercial Aviation Accidents: A Comprehensive, Fine-Grained Analysis Using HFACS

    DTIC Science & Technology

    2006-07-01

    recruited from the Oklahoma City area as subject-matter experts ( SMEs ). All were certified flight instructors with a minimum of 1,000 flight hours at...standing of specific terms, flight conditions, and the overall domain of aviation to be effectively classified and coded. As aviation SMEs , the pilot...the overall HFACS analysis of the commercial accident reports. Pilots, however, are not SMEs in the domain of psychol- ogy or human factors and may

  19. Preliminary analysis of graphite dust releasing behavior in accident for HTR

    SciTech Connect

    Peng, W.; Yang, X. Y.; Yu, S. Y.; Wang, J.

    2012-07-01

    The behavior of the graphite dust is important to the safety of High Temperature Gas-cooled Reactors. This study investigated the flow of graphite dust in helium mainstream. The analysis of the stresses acting on the graphite dust indicated that gas drag played the absolute leading role. Based on the understanding of the importance of gas drag, an experimental system is set up for the research of dust releasing behavior in accident. Air driven by centrifugal fan is used as the working fluid instead of helium because helium is expensive, easy to leak which make it difficult to seal. The graphite particles, with the size distribution same as in HTR, are added to the experiment loop. The graphite dust releasing behavior at the loss-of-coolant accident will be investigated by a sonic nozzle. (authors)

  20. Probabilistic accident consequence uncertainty analysis -- Uncertainty assessment for internal dosimetry. Volume 1: Main report

    SciTech Connect

    Goossens, L.H.J.; Kraan, B.C.P.; Cooke, R.M.; Harrison, J.D.; Harper, F.T.; Hora, S.C.

    1998-04-01

    The development of two new probabilistic accident consequence codes, MACCS and COSYMA, was completed in 1990. These codes estimate the consequence from the accidental releases of radiological material from hypothesized accidents at nuclear installations. In 1991, the US Nuclear Regulatory Commission and the Commission of the European Communities began cosponsoring a joint uncertainty analysis of the two codes. The ultimate objective of this joint effort was to systematically develop credible and traceable uncertainty distributions for the respective code input variables. A formal expert judgment elicitation and evaluation process was identified as the best technology available for developing a library of uncertainty distributions for these consequence parameters. This report focuses on the results of the study to develop distribution for variables related to the MACCS and COSYMA internal dosimetry models.

  1. Probabilistic accident consequence uncertainty analysis -- Late health effects uncertainty assessment. Volume 1: Main report

    SciTech Connect

    Little, M.P.; Muirhead, C.R.; Goossens, L.H.J.; Kraan, B.C.P.; Cooke, R.M.; Harper, F.T.; Hora, S.C.

    1997-12-01

    The development of two new probabilistic accident consequence codes, MACCS and COSYMA, was completed in 1990. These codes estimate the consequence from the accidental releases of radiological material from hypothesized accidents at nuclear installations. In 1991, the US Nuclear Regulatory Commission and the Commission of the European Communities began cosponsoring a joint uncertainty analysis of the two codes. The ultimate objective of this joint effort was to systematically develop credible and traceable uncertainty distributions for the respective code input variables. A formal expert judgment elicitation and evaluation process was identified as the best technology available for developing a library of uncertainty distributions for these consequence parameters. This report focuses on the results of the study to develop distribution for variables related to the MACCS and COSYMA late health effects models.

  2. Probabilistic accident consequence uncertainty analysis -- Early health effects uncertainty assessment. Volume 1: Main report

    SciTech Connect

    Haskin, F.E.; Harper, F.T.; Goossens, L.H.J.; Kraan, B.C.P.; Grupa, J.B.

    1997-12-01

    The development of two new probabilistic accident consequence codes, MACCS and COSYMA, was completed in 1990. These codes estimate the consequence from the accidental releases of radiological material from hypothesized accidents at nuclear installations. In 1991, the US Nuclear Regulatory Commission and the Commission of the European Communities began cosponsoring a joint uncertainty analysis of the two codes. The ultimate objective of this joint effort was to systematically develop credible and traceable uncertainty distributions for the respective code input variables. A formal expert judgment elicitation and evaluation process was identified as the best technology available for developing a library of uncertainty distributions for these consequence parameters. This report focuses on the results of the study to develop distribution for variables related to the MACCS and COSYMA early health effects models.

  3. Analysis of pedestrian accident costs in Sudan using the willingness-to-pay method.

    PubMed

    Mofadal, Adam I A; Kanitpong, Kunnawee; Jiwattanakulpaisarn, Piyapong

    2015-05-01

    The willingness-to-pay (WTP) with contingent valuation (CV) method has been proven to be a valid tool for the valuation of non-market goods or socio-economic costs of road traffic accidents among communities in developed and developing countries. Research on accident costing tends to estimate the value of statistical life (VOSL) for all road users by providing a principle for the evaluation of road safety interventions in cost-benefit analysis. As in many other developing countries, the economic loss of traffic accidents in Sudan is noticeable; however, analytical research to estimate the magnitude and impact of that loss is lacking. Reports have shown that pedestrians account for more than 40% of the total number of fatalities. In this study, the WTP-CV approach was used to determine the amount of money that pedestrians in Sudan are willing to pay to reduce the risk of their own death. The impact of the socioeconomic factors, risk levels, and walking behaviors of pedestrians on their WTP for fatality risk reduction was also evaluated. Data were collected from two cities-Khartoum and Nyala-using a survey questionnaire that included 1400 respondents. The WTP-CV Payment Card Questionnaire was designed to ensure that Sudan pedestrians can easily determine the amount of money that would be required to reduce the fatality risk from a pedestrian-related accident. The analysis results show that the estimated VOSL for Sudanese pedestrians ranges from US$0.019 to US$0.101 million. In addition, the willingness-to-pay by Sudanese pedestrians to reduce their fatality risk tends to increase with age, household income, educational level, safety perception, and average time spent on social activities with family and community.

  4. Analysis 320 coal mine accidents using structural equation modeling with unsafe conditions of the rules and regulations as exogenous variables.

    PubMed

    Zhang, Yingyu; Shao, Wei; Zhang, Mengjia; Li, Hejun; Yin, Shijiu; Xu, Yingjun

    2016-07-01

    Mining has been historically considered as a naturally high-risk industry worldwide. Deaths caused by coal mine accidents are more than the sum of all other accidents in China. Statistics of 320 coal mine accidents in Shandong province show that all accidents contain indicators of "unsafe conditions of the rules and regulations" with a frequency of 1590, accounting for 74.3% of the total frequency of 2140. "Unsafe behaviors of the operator" is another important contributory factor, which mainly includes "operator error" and "venturing into dangerous places." A systems analysis approach was applied by using structural equation modeling (SEM) to examine the interactions between the contributory factors of coal mine accidents. The analysis of results leads to three conclusions. (i) "Unsafe conditions of the rules and regulations," affect the "unsafe behaviors of the operator," "unsafe conditions of the equipment," and "unsafe conditions of the environment." (ii) The three influencing factors of coal mine accidents (with the frequency of effect relation in descending order) are "lack of safety education and training," "rules and regulations of safety production responsibility," and "rules and regulations of supervision and inspection." (iii) The three influenced factors (with the frequency in descending order) of coal mine accidents are "venturing into dangerous places," "poor workplace environment," and "operator error."

  5. SAS4A: A computer model for the analysis of hypothetical core disruptive accidents in liquid metal reactors

    SciTech Connect

    Tentner, A.M.; Birgersson, G.; Cahalan, J.E.; Dunn, F.E.; Kalimullah; Miles, K.J.

    1987-01-01

    To ensure that the public health and safety are protected under any accident conditions in a Liquid Metal Fast Breeder Reactor (LMFBR), many accidents are analyzed for their potential consequences. The SAS4A code system, described in this paper, provides such an analysis capability, including the ability to analyze low probability events such as the Hypothetical Core Disruptive Accidents (HCDAs). The SAS4A code system has been designed to simulate all the events that occur in a LMFBR core during the initiating phase of a Hypothetical Core Disruptive Accident. During such postulated accident scenarios as the Loss-of-Flow and Transient Overpower events, a large number of interrelated physical phenomena occur during a relatively short time. These phenomena include transient heat transfer and hydrodynamic events, coolant boiling and fuel and cladding melting and relocation. During to the strong neutronic feedback present in a nuclear reactor, these events can significantly influence the reactor power. The SAS4A code system is used in the safety analysis of nuclear reactors, in order to estimate the energetic potential of very low probability accidents. The results of SAS4A simulations are also used by reactor designers in order to build safer reactors and eliminate the possibility of any accident which could endanger the public safety.

  6. Light-Weight Radioisotope Heater Unit final safety analysis report (LWRHU-FSAR): Volume 2: Accident Model Document (AMD)

    SciTech Connect

    Johnson, E.W.

    1988-10-01

    The purpose of this volume of the LWRHU SAR, the Accident Model Document (AMD), are to: Identify all malfunctions, both singular and multiple, which can occur during the complete mission profile that could lead to release outside the clad of the radioisotopic material contained therein; Provide estimates of occurrence probabilities associated with these various accidents; Evaluate the response of the LWRHU (or its components) to the resultant accident environments; and Associate the potential event history with test data or analysis to determine the potential interaction of the released radionuclides with the biosphere.

  7. Independent assessment of MELCOR as a severe accident thermal-hydraulic/source term analysis tool

    SciTech Connect

    Madni, I.K.

    1995-11-01

    MELCOR is a fully integrated computer code that models all phases of the progression of severe accidents in light water reactor (LWR) nuclear power plants and is being developed for the US Nuclear Regulatory Commission (NRC) by Sandia National Laboratories. Brookhaven National Laboratory (BNL) has a program with the NRC called MELCOR Verification, Benchmarking, and Applications, the aim of which is to provide independent assessment of MELCOR as a severe accident thermal-hydraulic/source term analysis tool. The scope of this program is to perform quality control verification on all released versions of MELCOR, to benchmark MELCOR against more mechanistic codes and experimental data from severe fuel damage tests, and to evaluate the ability of MELCOR to simulate long-term severe accident transients in commercial LWRs, by applying the code to model both boiling water reactors and pressurized water reactors. Under this program, BNL provided input to the NRC-sponsored MELCOR Peer Review and is currently contributing to the MELCOR Cooperative Assessment Program (MCAP). A summary of MELCOR assessment efforts at BNL and their contribution to NRC goals with respect to MELCOR is presented.

  8. Independent assessment of MELCOR as a severe accident thermal-hydraulic/source term analysis tool

    SciTech Connect

    Madni, I.K.; Eltawila, F.

    1994-01-01

    MELCOR is a fully integrated computer code that models all phases of the progression of severe accidents in light water reactor nuclear power plants, and is being developed for the US Nuclear Regulatory Commission (NRC) by Sandia National Laboratories (SNL). Brookhaven National Laboratory (BNL) has a program with the NRC called ``MELCOR Verification, Benchmarking, and Applications,`` whose aim is to provide independent assessment of MELCOR as a severe accident thermal-hydraulic/source term analysis tool. The scope of this program is to perform quality control verification on all released versions of MELCOR, to benchmark MELCOR against more mechanistic codes and experimental data from severe fuel damage tests, and to evaluate the ability of MELCOR to simulate long-term severe accident transients in commercial LWRs, by applying the code to model both BWRs and PWRs. Under this program, BNL provided input to the NRC-sponsored MELCOR Peer Review, and is currently contributing to the MELCOR Cooperative Assessment Program (MCAP). This paper presents a summary of MELCOR assessment efforts at BNL and their contribution to NRC goals with respect to MELCOR.

  9. Verification of fire and explosion accident analysis codes (facility design and preliminary results)

    SciTech Connect

    Gregory, W.S.; Nichols, B.D.; Talbott, D.V.; Smith, P.R.; Fenton, D.L.

    1985-01-01

    For several years, the US Nuclear Regulatory Commission has sponsored the development of methods for improving capabilities to analyze the effects of postulated accidents in nuclear facilities; the accidents of interest are those that could occur during nuclear materials handling. At the Los Alamos National Laboratory, this program has resulted in three computer codes: FIRAC, EXPAC, and TORAC. These codes are designed to predict the effects of fires, explosions, and tornadoes in nuclear facilities. Particular emphasis is placed on the movement of airborne radioactive material through the gaseous effluent treatment system of a nuclear installation. The design, construction, and calibration of an experimental ventilation system to verify the fire and explosion accident analysis codes are described. The facility features a large industrial heater and several aerosol smoke generators that are used to simulate fires. Both injected thermal energy and aerosol mass can be controlled using this equipment. Explosions are simulated with H/sub 2//O/sub 2/ balloons and small explosive charges. Experimental measurements of temperature, energy, aerosol release rates, smoke concentration, and mass accumulation on HEPA filters can be made. Volumetric flow rate and differential pressures also are monitored. The initial experiments involve varying parameters such as thermal and aerosol rate and ventilation flow rate. FIRAC prediction results are presented. 10 figs.

  10. Analysis of National Major Work Safety Accidents in China, 2003–2012

    PubMed Central

    YE, Yunfeng; ZHANG, Siheng; RAO, Jiaming; WANG, Haiqing; LI, Yang; WANG, Shengyong; DONG, Xiaomei

    2016-01-01

    Background: This study provides a national profile of major work safety accidents in China, which cause more than 10 fatalities per accident, intended to provide scientific basis for prevention measures and strategies to reduce major work safety accidents and deaths. Methods: Data from 2003–2012 Census of major work safety accidents were collected from State Administration of Work Safety System (SAWS). Published literature and statistical yearbook were also included to implement information. We analyzed the frequency of accidents and deaths, trend, geographic distribution and injury types. Additionally, we discussed the severity and urgency of emergency rescue by types of accidents. Results: A total of 877 major work safety accidents were reported, resulting in 16,795 deaths and 9,183 injuries. The numbers of accidents and deaths, mortality rate and incidence of major accidents have declined in recent years. The mortality rate and incidence was 0.71 and 1.20 per 106 populations in 2012, respectively. Transportation and mining contributed to the highest number of major accidents and deaths. Major aviation and railway accidents caused more casualties per incident, while collapse, machinery, electrical shock accidents and tailing dam accidents were the most severe situation that resulted in bigger proportion of death. Conclusion: Ten years’ major work safety accident data indicate that the frequency of accidents and number of eaths was declined and several safety concerns persist in some segments. PMID:27057515

  11. Accident consequences analysis of the HYLIFE-II inertial fusion energy power plant design

    SciTech Connect

    Reyes, S; Gomez del Rio, J; Sanz, J

    2000-02-23

    Previous studies of the safety and environmental (S and E) aspects of the HYLIFE-II inertial fusion energy (IFE) power plant design have used simplistic assumptions in order to estimate radioactivity releases under accident conditions. Conservatisms associated with these traditional analyses can mask the actual behavior of the plant and have revealed the need for more accurate modeling and analysis of accident conditions and radioactivity mobilization mechanisms. In the present work a set of computer codes traditionally used for magnetic fusion safety analyses (CHEMCON, MELCOR) has been applied for simulating accident conditions in a simple model of the HYLIFE-II IFE design. Here the authors consider a severe lost of coolant accident (LOCA) producing simultaneous failures of the beam tubes (providing a pathway for radioactivity release from the vacuum vessel towards the containment) and of the two barriers surrounding the chamber (inner shielding and containment building it self). Even though containment failure would be a very unlikely event it would be needed in order to produce significant off-site doses. CHEMCON code allows calculation of long-term temperature transients in fusion reactor first wall, blanket, and shield structures resulting from decay heating. MELCOR is used to simulate a wide range of physical phenomena including thermal-hydraulics, heat transfer, aerosol physics and fusion product release and transport. The results of these calculations show that the estimated off-site dose is less than 6 mSv (0.6 rem), which is well below the value of 10 mSv (1 rem) given by the DOE Fusion Safety Standards for protection of the public from exposure to radiation during off-normal conditions.

  12. Operator error and system deficiencies: analysis of 508 mining incidents and accidents from Queensland, Australia using HFACS.

    PubMed

    Patterson, Jessica M; Shappell, Scott A

    2010-07-01

    Historically, mining has been viewed as an inherently high-risk industry. Nevertheless, the introduction of new technology and a heightened concern for safety has yielded marked reductions in accident and injury rates over the last several decades. In an effort to further reduce these rates, the human factors associated with incidents/accidents needs to be addressed. A modified version of the Human Factors Analysis and Classification System was used to analyze incident and accident cases from across the state of Queensland to identify human factor trends and system deficiencies within mining. An analysis of the data revealed that skill-based errors were the most common unsafe act and showed no significant differences across mine types. However, decision errors did vary across mine types. Findings for unsafe acts were consistent across the time period examined. By illuminating human causal factors in a systematic fashion, this study has provided mine safety professionals the information necessary to reduce mine incidents/accidents further.

  13. Radiation protection: an analysis of thyroid blocking. [Effectiveness of KI in reducing radioactive uptake following potential reactor accident

    SciTech Connect

    Aldrich, D C; Blond, R M

    1980-01-01

    An analysis was performed to provide guidance to policymakers concerning the effectiveness of potassium iodide (KI) as a thyroid blocking agent in potential reactor accident situations, the distance to which (or area within which) it should be distributed, and its relative effectiveness compared to other available protective measures. The analysis was performed using the Reactor Safety Study (WASH-1400) consequence model. Four categories of accidents were addressed: gap activity release accident (GAP), GAP without containment isolation, core melt with a melt-through release, and core melt with an atmospheric release. Cost-benefit ratios (US $/thyroid nodule prevented) are given assuming that no other protective measures are taken. Uncertainties due to health effects parameters, accident probabilities, and costs are assessed. The effects of other potential protective measures, such as evacuation and sheltering, and the impact on children (critical population) are evaluated. Finally, risk-benefit considerations are briefly discussed.

  14. Model building techniques for analysis.

    SciTech Connect

    Walther, Howard P.; McDaniel, Karen Lynn; Keener, Donald; Cordova, Theresa Elena; Henry, Ronald C.; Brooks, Sean; Martin, Wilbur D.

    2009-09-01

    The practice of mechanical engineering for product development has evolved into a complex activity that requires a team of specialists for success. Sandia National Laboratories (SNL) has product engineers, mechanical designers, design engineers, manufacturing engineers, mechanical analysts and experimentalists, qualification engineers, and others that contribute through product realization teams to develop new mechanical hardware. The goal of SNL's Design Group is to change product development by enabling design teams to collaborate within a virtual model-based environment whereby analysis is used to guide design decisions. Computer-aided design (CAD) models using PTC's Pro/ENGINEER software tools are heavily relied upon in the product definition stage of parts and assemblies at SNL. The three-dimensional CAD solid model acts as the design solid model that is filled with all of the detailed design definition needed to manufacture the parts. Analysis is an important part of the product development process. The CAD design solid model (DSM) is the foundation for the creation of the analysis solid model (ASM). Creating an ASM from the DSM currently is a time-consuming effort; the turnaround time for results of a design needs to be decreased to have an impact on the overall product development. This effort can be decreased immensely through simple Pro/ENGINEER modeling techniques that summarize to the method features are created in a part model. This document contains recommended modeling techniques that increase the efficiency of the creation of the ASM from the DSM.

  15. The Application of Electron Microscopy Techniques to the Space Shuttle Columbia Accident Investigation

    NASA Technical Reports Server (NTRS)

    Shah, Sandeep; Jerman, Greg

    2005-01-01

    The Space Shuttle Columbia was returning from a 16-day research mission, STS- 107, with nominal system performance prior to the beginning of the entry interface into earth's upper atmosphere. Approximately one minute and twenty four seconds into the peak heating region of the entry interface, an off-nominal temperature rise was observed in the left main landing gear brake line. Nearly seven minutes later, all contact was lost with Columbia. Debris was observed periodically exiting the Shuttle's flight path throughout the reentry profile over California, Nevada, and New Mexico, until its final breakup over Texas. During the subsequent investigation, electron microscopy techniques were crucial in revealing the location of the fatal damage that resulted in the loss of Columbia and her crew.

  16. Light-Weight Radioisotope Heater Unit Safety Analysis Report (LWRHU-SAR). Volume II. Accident model document

    SciTech Connect

    Johnson, E.W.

    1985-10-01

    Purposes of this volume (AMD), are to: Identify all malfunctions, both singular and multiple, which can occur during the complete mission profile that could lead to release outside the clad of the radioisotopic material contained therein; provide estimates of occurrence probabilities associated with these various accidents; evaluate the response of the LWRHU (or its components) to the resultant accident environments; and associate the potential event history with test data or analysis to determine the potential interaction of the released radionuclides with the biosphere.

  17. Techniques for Automated Performance Analysis

    SciTech Connect

    Marcus, Ryan C.

    2014-09-02

    The performance of a particular HPC code depends on a multitude of variables, including compiler selection, optimization flags, OpenMP pool size, file system load, memory usage, MPI configuration, etc. As a result of this complexity, current predictive models have limited applicability, especially at scale. We present a formulation of scientific codes, nodes, and clusters that reduces complex performance analysis to well-known mathematical techniques. Building accurate predictive models and enhancing our understanding of scientific codes at scale is an important step towards exascale computing.

  18. Progress in Addressing DNFSB Recommendation 2002-1 Issues: Improving Accident Analysis Software Applications

    SciTech Connect

    VINCENT, ANDREW

    2005-04-25

    Defense Nuclear Facilities Safety Board (DNFSB) Recommendation 2002-1 (''Quality Assurance for Safety-Related Software'') identified a number of quality assurance issues on the use of software in Department of Energy (DOE) facilities for analyzing hazards, and designing and operating controls to prevent or mitigate potential accidents. Over the last year, DOE has begun several processes and programs as part of the Implementation Plan commitments, and in particular, has made significant progress in addressing several sets of issues particularly important in the application of software for performing hazard and accident analysis. The work discussed here demonstrates that through these actions, Software Quality Assurance (SQA) guidance and software tools are available that can be used to improve resulting safety analysis. Specifically, five of the primary actions corresponding to the commitments made in the Implementation Plan to Recommendation 2002-1 are identified and discussed in this paper. Included are the web-based DOE SQA Knowledge Portal and the Central Registry, guidance and gap analysis reports, electronic bulletin board and discussion forum, and a DOE safety software guide. These SQA products can benefit DOE safety contractors in the development of hazard and accident analysis by precluding inappropriate software applications and utilizing best practices when incorporating software results to safety basis documentation. The improvement actions discussed here mark a beginning to establishing stronger, standard-compliant programs, practices, and processes in SQA among safety software users, managers, and reviewers throughout the DOE Complex. Additional effort is needed, however, particularly in: (1) processes to add new software applications to the DOE Safety Software Toolbox; (2) improving the effectiveness of software issue communication; and (3) promoting a safety software quality assurance culture.

  19. Analysis of Maximum Reasonably Foreseeable Accidents for the Yucca Mountain Draft Environmental Impact Statement (DEIS)

    SciTech Connect

    S.B. Ross; R.E. Best; S.J. Maheras; T.I. McSweeney

    2001-08-17

    Accidents could occur during the transportation of spent nuclear fuel and high-level radioactive waste. This paper describes the risks and consequences to the public from accidents that are highly unlikely but that could have severe consequences. The impact of these accidents would include those to a collective population and to hypothetical maximally exposed individuals (MEIs). This document discusses accidents with conditions that have a chance of occurring more often than 1 in 10 million times in a year, called ''maximum reasonably foreseeable accidents''. Accidents and conditions less likely than this are not considered to be reasonably foreseeable.

  20. Visualization of Traffic Accidents

    NASA Technical Reports Server (NTRS)

    Wang, Jie; Shen, Yuzhong; Khattak, Asad

    2010-01-01

    Traffic accidents have tremendous impact on society. Annually approximately 6.4 million vehicle accidents are reported by police in the US and nearly half of them result in catastrophic injuries. Visualizations of traffic accidents using geographic information systems (GIS) greatly facilitate handling and analysis of traffic accidents in many aspects. Environmental Systems Research Institute (ESRI), Inc. is the world leader in GIS research and development. ArcGIS, a software package developed by ESRI, has the capabilities to display events associated with a road network, such as accident locations, and pavement quality. But when event locations related to a road network are processed, the existing algorithm used by ArcGIS does not utilize all the information related to the routes of the road network and produces erroneous visualization results of event locations. This software bug causes serious problems for applications in which accurate location information is critical for emergency responses, such as traffic accidents. This paper aims to address this problem and proposes an improved method that utilizes all relevant information of traffic accidents, namely, route number, direction, and mile post, and extracts correct event locations for accurate traffic accident visualization and analysis. The proposed method generates a new shape file for traffic accidents and displays them on top of the existing road network in ArcGIS. Visualization of traffic accidents along Hampton Roads Bridge Tunnel is included to demonstrate the effectiveness of the proposed method.

  1. Analysis of the source range monitor during the first four hours of the Three Mile Island Unit 2 accident

    SciTech Connect

    Wu, H.Y.; Bandini, B.R. ); Hsiao, M.Y.; Baratta, A.J.; Bandini, B.R. . Dept. of Nuclear Engineering); Tolman, E.L. )

    1989-02-01

    The source range monitor (SRM) data recorded during the first 4 h of the Three Mile Island Unit 2 (TMI-2) accident following reactor shutdown were analyzed. An effort to simulate the actual SRM response was made by performing a series of neutron transport calculations. Primary emphasis was placed on simulating the changes in SRM response to various system events during the accident so as to obtain useful information about core conditions at the various stages. Based on the known end-state reactor conditions, the major system events and the actual SRM readings, self-consistent estimates were made of core liquid level, void fraction in the coolant, and locations of core materials. This analysis expands the possible interpretation of the SRM data relative to core damage progression. The results appear to be consistent with other studies of the TMI-2 Accident Evaluation Program, and provide information useful for the development and determination of the TMI-2 accident scenario.

  2. Source term analysis for a criticality accident in metal production line glove boxes

    SciTech Connect

    Nguyen, D.H.

    1991-06-01

    A recent development in criticality accident analysis is the deterministic calculations of the transport of fission products and actinides through the barriers of the physical facility. The knowledge of the redistribution of the materials inside the facility will help determine the reentry and clean-up procedures. The amount of radioactive materials released to the environment is the source term for dispersion calculations. We have used an integrated computer model to determine the release of fission products to the environment from a hypothetical criticality event in a glove box of the metal production line (MPL) at the Lawrence Livermore National Laboratory (LLNL).

  3. Quantitative uncertainty and sensitivity analysis of a PWR control rod ejection accident

    SciTech Connect

    Pasichnyk, I.; Perin, Y.; Velkov, K.

    2013-07-01

    The paper describes the results of the quantitative Uncertainty and Sensitivity (U/S) Analysis of a Rod Ejection Accident (REA) which is simulated by the coupled system code ATHLET-QUABOX/CUBBOX applying the GRS tool for U/S analysis SUSA/XSUSA. For the present study, a UOX/MOX mixed core loading based on a generic PWR is modeled. A control rod ejection is calculated for two reactor states: Hot Zero Power (HZP) and 30% of nominal power. The worst cases for the rod ejection are determined by steady-state neutronic simulations taking into account the maximum reactivity insertion in the system and the power peaking factor. For the U/S analysis 378 uncertain parameters are identified and quantified (thermal-hydraulic initial and boundary conditions, input parameters and variations of the two-group cross sections). Results for uncertainty and sensitivity analysis are presented for safety important global and local parameters. (authors)

  4. Bayesian spatial and ecological models for small-area accident and injury analysis.

    PubMed

    MacNab, Ying C

    2004-11-01

    In this article, recently developed Bayesian spatial and ecological regression models are applied to analyse small-area variation in accident and injury. This study serves to demonstrate how Bayesian modelling techniques can be implemented to assess potential risk factors measured at group (e.g. area) level. Presented here is a unified modelling framework that enables thorough investigations into associations between injury rates and regional characteristics, residual variation and spatial autocorrelation. Using hospital separation data for 83 local health areas in British Columbia (BC), Canada, in 1990-1999, we explore and examine ecological/contextual determinants of motor vehicle accident injury (MVAI) among male children and youth aged 0-24 and for those of six age groups (<1, 1-4, 5-9, 10-14, 15-19 and 20-24). Eighteen local health area characteristics are studied. They include a broad spectrum of socio-economic indicators, residential environment indicators (roads and parks), medical services availability and utilisation, population health, proportion of recent immigrants, crime rates, rates of speeding charge and rates of seatbelt violation. Our study indicates a large regional variation in MVAI in males aged 0-24 in British Columbia, Canada, in 1990-1999, and that adjusting for appropriate risk factors eliminates nearly all the variation observed. Socio-economic influence on MVAI was profoundly apparent in young males of all ages with the injury being more common in communities of lower socio-economic status. High adult male crime rates were significantly associated with high injury rates of boys aged 1-14. Seatbelt violations and excess speeding charges were found to be positively associated with the injury rates of young men aged 20-24. This and similar ecological studies shed light on reasons for regional variations in accident occurrence as well as in the resulting injuries and hospital utilisation. Thereby they are potentially useful in identifying

  5. Narrative text analysis of accident reports with tractors, self-propelled harvesting machinery and materials handling machinery in Austrian agriculture from 2008 to 2010 - a comparison.

    PubMed

    Mayrhofer, Hannes; Quendler, Elisabeth; Boxberger, Josef

    2014-01-01

    The aim of this study was the identification of accident scenarios and causes by analysing existing accident reports of recognized agricultural occupational accidents with tractors, self-propelled harvesting machinery and materials handling machinery from 2008 to 2010. As a result of a literature-based evaluation of past accident analyses, the narrative text analysis was chosen as an appropriate method. A narrative analysis of the text fields of accident reports that farmers used to report accidents to insurers was conducted to obtain detailed information about the scenarios and causes of accidents. This narrative analysis of reports was made the first time and yielded first insights for identifying antecedents of accidents and potential opportunities for technical based intervention. A literature and internet search was done to discuss and confirm the findings. The narrative text analysis showed that in more than one third of the accidents with tractors and materials handling machinery the vehicle rolled or tipped over. The most relevant accident scenarios with harvesting machinery were being trapped and falling down. The direct comparison of the analysed machinery categories showed that more than 10% of the accidents in each category were caused by technical faults, slippery or muddy terrain and incorrect or inappropriate operation of the vehicle. Accidents with tractors, harvesting machinery and materials handling machinery showed similarities in terms of causes, circumstances and consequences. Certain technical and communicative measures for accident prevention could be used for all three machinery categories. Nevertheless, some individual solutions for accident prevention, which suit each specific machine type, would be necessary.

  6. A Content Analysis of News Media Coverage of the Accident at Three Mile Island.

    ERIC Educational Resources Information Center

    Stephens, Mitchell; Edison, Nadyne G.

    A study was conducted for the President's Commission on the Accident at Three Mile Island to analyze coverage of the accident by ten news organizations: two wire services, three commercial television networks, and five daily newspapers. Copies of all stories and transcripts of news programs during the first week of the accident were examined from…

  7. Analysis of Occupational Accident Fatalities and Injuries Among Male Group in Iran Between 2008 and 2012

    PubMed Central

    Alizadeh, Seyed Shamseddin; Mortazavi, Seyed Bagher; Sepehri, Mohammad Mehdi

    2015-01-01

    Background: Because of occupational accidents, permanent disabilities and deaths occur and economic and workday losses emerge. Objectives: The purpose of the present study was to investigate the factors responsible for occupational accidents occurred in Iran. Patients and Methods: The current study analyzed 1464 occupational accidents recorded by the Ministry of Labor and Social Affairs’ offices in Iran during 2008 - 2012. At first, general understanding of accidents was obtained using descriptive statistics. Afterwards, the chi-square test and Cramer’s V statistic (Vc) were used to determine the association between factors influencing the type of injury as occupational accident outcomes. Results: There was no significant association between marital status and time of day with the type of injury. However, activity sector, cause of accident, victim’s education, age of victim and victim’s experience were significantly associated with the type of injury. Conclusions: Successful accident prevention relies largely on knowledge about the causes of accidents. In any accident control activity, particularly in occupational accidents, correctly identifying high-risk groups and factors influencing accidents is the key to successful interventions. Results of this study can cause to increase accident awareness and enable workplace’s management to select and prioritize problem areas and safety system weakness in workplaces. PMID:26568848

  8. Analysis of Kuosheng Large-Break Loss-of-Coolant Accident with MELCOR 1.8.4

    SciTech Connect

    Wang, T.-C.; Wang, S.-J.; Chien, C.-S

    2000-09-15

    The MELCOR code, developed by Sandia National Laboratories, is capable of simulating the severe accident phenomena of light water reactor nuclear power plants (NPPs). A specific large-break loss-of-coolant accident (LOCA) for Kuosheng NPP is simulated with the use of the MELCOR 1.8.4 code. This accident is induced by a double-ended guillotine break of one of the recirculation pipes concurrent with complete failure of the emergency core cooling system. The MELCOR input deck for the Kuosheng NPP is established based on the design data of the Kuosheng NPP and the MELCOR users' guides. The initial steady-state conditions are generated with a developed self-initialization algorithm. The effect of the MELCOR 1.8.4-provided initialization process is demonstrated. The main severe accident phenomena and the corresponding fission product released fractions associated with the large-break LOCA sequences are simulated. The MELCOR 1.8.4 predicts a longer time interval between the core collapse and vessel failure and a higher source term. This MELCOR 1.8.4 input deck will be applied to the probabilistic risk assessment, the severe accident analysis, and the severe accident management study of the Kuosheng NPP in the near future.

  9. MELCOR Analysis of Steam Generator Tube Creep Rupture in Station Blackout Severe Accident

    SciTech Connect

    Liao, Y.; Vierow, K.

    2005-12-15

    A pressurized water reactor steam generator tube rupture (SGTR) is of concern because it represents a bypass of the containment for radioactive materials to the environment. In a station blackout accident, tube integrity could be threatened by creep rupture, particularly if cracks are present in the tube walls. Methods are developed herein to improve assessment capabilities for SGTR by using the severe-accident code MELCOR. Best-estimate assumptions based on recent research and computational fluid dynamics calculations are applied in the MELCOR analysis to simulate two-dimensional natural circulation and to determine the relative creep-rupture timing in the reactor coolant pressure boundary components. A new method is developed to estimate the steam generator (SG) hottest tube wall temperature and the tube critical crack size for the SG tubes to fail first. The critical crack size for SG tubes to fail first is estimated to be 20% of the wall thickness larger than by a previous analysis. Sensitivity studies show that the failure sequence would change if some assumptions are modified. In particular, the uncertainty in the countercurrent flow limit model could reverse the failure sequence of the SG tubes and surge line.

  10. NASA Structural Analysis Report on the American Airlines Flight 587 Accident - Local Analysis of the Right Rear Lug

    NASA Technical Reports Server (NTRS)

    Raju, Ivatury S; Glaessgen, Edward H.; Mason, Brian H; Krishnamurthy, Thiagarajan; Davila, Carlos G

    2005-01-01

    A detailed finite element analysis of the right rear lug of the American Airlines Flight 587 - Airbus A300-600R was performed as part of the National Transportation Safety Board s failure investigation of the accident that occurred on November 12, 2001. The loads experienced by the right rear lug are evaluated using global models of the vertical tail, local models near the right rear lug, and a global-local analysis procedure. The right rear lug was analyzed using two modeling approaches. In the first approach, solid-shell type modeling is used, and in the second approach, layered-shell type modeling is used. The solid-shell and the layered-shell modeling approaches were used in progressive failure analyses (PFA) to determine the load, mode, and location of failure in the right rear lug under loading representative of an Airbus certification test conducted in 1985 (the 1985-certification test). Both analyses were in excellent agreement with each other on the predicted failure loads, failure mode, and location of failure. The solid-shell type modeling was then used to analyze both a subcomponent test conducted by Airbus in 2003 (the 2003-subcomponent test) and the accident condition. Excellent agreement was observed between the analyses and the observed failures in both cases. From the analyses conducted and presented in this paper, the following conclusions were drawn. The moment, Mx (moment about the fuselage longitudinal axis), has significant effect on the failure load of the lugs. Higher absolute values of Mx give lower failure loads. The predicted load, mode, and location of the failure of the 1985-certification test, 2003-subcomponent test, and the accident condition are in very good agreement. This agreement suggests that the 1985-certification and 2003- subcomponent tests represent the accident condition accurately. The failure mode of the right rear lug for the 1985-certification test, 2003-subcomponent test, and the accident load case is identified as a

  11. Accident Analysis Simulation in Modular 300MWt Gas Cooled Fast Reactor

    NASA Astrophysics Data System (ADS)

    Zaki, Su’ud

    2017-01-01

    Safety analysis of 300MWt helium gas cooled long-life fast reactors has been performed. The analysis of unprotected loss of flow(ULOF) and unprotected rod run-out transient overpower (UTOP) are discussed. Some simulations for 300 MWt He gas cooled fast reactors has been performed and the results show that the reactor can anticipate complete pumping failure inherently by reducing power through reactivity feedback and remove the rest of heat through natural circulations. GCFR relatively has hard spectrum so it has relatively small Doppler coefficient. In the UTOP accident case the analysis has been performed against external reactivity up to 0.002dk/k. In addition the steam generator design has also consider excess power during severe UTOP case..

  12. Feasibility study on phyto-remediation techniques for soil contaminated by the Fukushima Dai-Ichi nuclear power plant accident

    SciTech Connect

    Yuu Ishimori; Akihiro Sakoda; Mina Yamada; Yuko Makino; Satoshi Yamada; Hideyasu Fujiyama

    2013-07-01

    Tottori University and the Japan Atomic Energy Agency carried out jointly the feasibility study on phyto-remediation techniques, which apply to soil contaminated by the TEPCO's Fukushima Dai-ichi NPP accident. This paper illustrates the results from experimental investigations. Experimental investigations include both water-culture tests and field tests. Several plants, mainly halophytes that can specifically absorb more Na than K, and others like sunflower demonstrated for other domestic large-scale tests, were water-cultured and examined for screening. Easily cultivated and harvested plants without harmful effects on subsequent cultivation were also considered. New Zealand spinach was selected as a candidate for demonstrations in fields. The field tests were carried out at two sites of different agricultural types in Minami-soma, Fukushima prefecture. Concentration of {sup 137}Cs in soil is about 4.5 Bq/g-dry as the average of 10 cm depth. The aims of the field tests are to confirm absorption ability and environmental adaptation of the test plants and to document the cost and performance of projects. In conclusion, the absorption of {sup 137}Cs activity per unit area (Bq/m{sup 2}) by New Zealand spinach could be approximately 0.5%. To achieve an effective result in removal of {sup 137}Cs from soil in around a decade, it is required to find the plant which has ten or more times higher absorption capacity than New Zealand spinach. From the consistency of both results in water-culture and field tests, the water-culture test can be valid for screening. In addition, applicable sites will be limited to fields which are too steep or too narrow to use mechanical diggers, and which are free from any restrictions to enter. (authors)

  13. Electrical equipment performance under severe accident conditions (BWR/Mark 1 plant analysis): Summary report

    SciTech Connect

    Bennett, P.R.; Kolaczkowski, A.M.; Medford, G.T.

    1986-09-01

    The purpose of the Performance Evaluation of Electrical Equipment during Severe Accident States Program is to determine the performance of electrical equipment, important to safety, under severe accident conditions. In FY85, a method was devised to identify important electrical equipment and the severe accident environments in which the equipment was likely to fail. This method was used to evaluate the equipment and severe accident environments for Browns Ferry Unit 1, a BWR/Mark I. Following this work, a test plan was written in FY86 to experimentally determine the performance of one selected component to two severe accident environments.

  14. The Gulf of Mexico oil rig accident: analysis by different SAR satellite images

    NASA Astrophysics Data System (ADS)

    Del Frate, Fabio; Giacomini, Andrea; Latini, Daniele; Solimini, Domenico; Emery, William J.

    2011-11-01

    The management of the monitoring oil spills over the sea surface is a very important and actual task for international environmental agencies, due to the continuous risks represented by possible accidents involving either rigs or tankers. On the other hand the increase of remote sensing space missions can definitely improve our capabilities in this kind of activity. In this paper we consider the dramatic Gulf of Mexico oil spill event of 2010 to investigate on the types of information that could be provided by the available SAR images collection which included different polarizations and bands. With an eye to the implementation of fully automatic processing chains, an assessment of a novel segmentation technique based on PCNN (Pulse Coupled Neural Networks) was also carried out.

  15. Probabilistic accident consequence uncertainty analysis -- Early health effects uncertainty assessment. Volume 2: Appendices

    SciTech Connect

    Haskin, F.E.; Harper, F.T.; Goossens, L.H.J.; Kraan, B.C.P.

    1997-12-01

    The development of two new probabilistic accident consequence codes, MACCS and COSYMA, was completed in 1990. These codes estimate the consequence from the accidental releases of radiological material from hypothesized accidents at nuclear installations. In 1991, the US Nuclear Regulatory Commission and the Commission of the European Communities began cosponsoring a joint uncertainty analysis of the two codes. The ultimate objective of this joint effort was to systematically develop credible and traceable uncertainty distributions for the respective code input variables. A formal expert judgment elicitation and evaluation process was identified as the best technology available for developing a library of uncertainty distributions for these consequence parameters. This report focuses on the results of the study to develop distribution for variables related to the MACCS and COSYMA early health effects models. This volume contains appendices that include (1) a summary of the MACCS and COSYMA consequence codes, (2) the elicitation questionnaires and case structures, (3) the rationales and results for the panel on early health effects, (4) short biographies of the experts, and (5) the aggregated results of their responses.

  16. Probabilistic accident consequence uncertainty analysis -- Uncertainty assessment for deposited material and external doses. Volume 2: Appendices

    SciTech Connect

    Goossens, L.H.J.; Kraan, B.C.P.; Cooke, R.M.; Boardman, J.; Jones, J.A.; Harper, F.T.; Young, M.L.; Hora, S.C.

    1997-12-01

    The development of two new probabilistic accident consequence codes, MACCS and COSYMA, was completed in 1990. These codes estimate the consequence from the accidental releases of radiological material from hypothesized accidents at nuclear installations. In 1991, the US Nuclear Regulatory Commission and the Commission of the European Communities began cosponsoring a joint uncertainty analysis of the two codes. The ultimate objective of this joint effort was to systematically develop credible and traceable uncertainty distributions for the respective code input variables. A formal expert judgment elicitation and evaluation process was identified as the best technology available for developing a library of uncertainty distributions for these consequence parameters. This report focuses on the results of the study to develop distribution for variables related to the MACCS and COSYMA deposited material and external dose models. This volume contains appendices that include (1) a summary of the MACCS and COSYMA consequence codes, (2) the elicitation questionnaires and case structures, (3) the rationales and results for the panel on deposited material and external doses, (4) short biographies of the experts, and (5) the aggregated results of their responses.

  17. Probabilistic accident consequence uncertainty analysis -- Late health effects uncertain assessment. Volume 2: Appendices

    SciTech Connect

    Little, M.P.; Muirhead, C.R.; Goossens, L.H.J.; Kraan, B.C.P.; Cooke, R.M.; Harper, F.T.; Hora, S.C.

    1997-12-01

    The development of two new probabilistic accident consequence codes, MACCS and COSYMA, was completed in 1990. These codes estimate the consequence from the accidental releases of radiological material from hypothesized accidents at nuclear installations. In 1991, the US Nuclear Regulatory Commission and the Commission of the European Communities began cosponsoring a joint uncertainty analysis of the two codes. The ultimate objective of this joint effort was to systematically develop credible and traceable uncertainty distributions for the respective code input variables. A formal expert judgment elicitation and evaluation process was identified as the best technology available for developing a library of uncertainty distributions for these consequence parameters. This report focuses on the results of the study to develop distribution for variables related to the MACCS and COSYMA late health effects models. This volume contains appendices that include (1) a summary of the MACCS and COSYMA consequence codes, (2) the elicitation questionnaires and case structures, (3) the rationales and results for the expert panel on late health effects, (4) short biographies of the experts, and (5) the aggregated results of their responses.

  18. Learning from the Piper Alpha accident: A postmortem analysis of technical and organizational factors

    SciTech Connect

    Pate-Cornell, M.E. )

    1993-04-01

    The accident that occurred on board the offshore platform Piper Alpha in July 1988 killed 167 people and cost billions of dollars in property damage. It was caused by a massive fire, which was not the result of an unpredictable act of God' but of an accumulation of errors and questionable decisions. Most of them were rooted in the organization, its structure, procedures, and culture. This paper analyzes the accident scenario using the risk analysis framework, determines which human decision and actions influenced the occurrence of the basic events, and then identifies the organizational roots of these decisions and actions. These organizational factors are generalizable to other industries and engineering systems. They include flaws in the design guidelines and design practices (e.g., tight physical couplings or insufficient redundancies), misguided priorities in the management of the tradeoff between productivity and safety, mistakes in the management of the personnel on board, and errors of judgement in the process by which financial pressures are applied on the production sector (i.e., the oil companies' definition of profit centers) resulting in deficiencies in inspection and maintenance operations. This analytical approach allows identification of risk management measures that go beyond the purely technical (e.g., add redundancies to a safety system) and also include improvements of management practices. 18 refs., 4 figs.

  19. Probabilistic accident consequence uncertainty analysis -- Uncertainty assessment for internal dosimetry. Volume 2: Appendices

    SciTech Connect

    Goossens, L.H.J.; Kraan, B.C.P.; Cooke, R.M.; Harrison, J.D.; Harper, F.T.; Hora, S.C.

    1998-04-01

    The development of two new probabilistic accident consequence codes, MACCS and COSYMA, was completed in 1990. These codes estimate the consequence from the accidental releases of radiological material from hypothesized accidents at nuclear installations. In 1991, the US Nuclear Regulatory Commission and the Commission of the European Communities began cosponsoring a joint uncertainty analysis of the two codes. The ultimate objective of this joint effort was to systematically develop credible and traceable uncertainty distributions for the respective code input variables. A formal expert judgment elicitation and evaluation process was identified as the best technology available for developing a library of uncertainty distributions for these consequence parameters. This report focuses on the results of the study to develop distribution for variables related to the MACCS and COSYMA internal dosimetry models. This volume contains appendices that include (1) a summary of the MACCS and COSYMA consequence codes, (2) the elicitation questionnaires and case structures, (3) the rationales and results for the panel on internal dosimetry, (4) short biographies of the experts, and (5) the aggregated results of their responses.

  20. Prefractionation techniques in proteome analysis.

    PubMed

    Righetti, Pier Giorgio; Castagna, Annalisa; Herbert, Ben; Reymond, Frederic; Rossier, Joël S

    2003-08-01

    The present review deals with a number of prefractionation protocols in preparation for two-dimensional map analysis, both in the fields of chromatography and in the field of electrophoresis. In the first case, Fountoulaki's groups has reported just about any chromatographic procedure useful as a prefractionation step, including affinity, ion-exchange, and reversed-phase resins. As a result of the various enrichment steps, several hundred new species, previously undetected in unfractionated samples, could be revealed for the first time. Electrophoretic prefractionation protocols include all those electrokinetic methodologies which are performed in free solution, essentially all relying on isoelectric focusing steps. The devices here reviewed include multichamber apparatus, such as the multicompartment electrolyzer with Immobiline membranes, Off-Gel electrophoresis in a multicup device and the Rotofor, an instrument also based on a multichamber system but exploiting the conventional technique of carrier-ampholyte-focusing. Other instruments of interest are the Octopus, a continuous-flow device for isoelectric focusing in a upward flowing liquid curtain, and the Gradiflow, where different pI cuts are obtained by a multistep passage through two compartments buffered at different pH values. It is felt that this panoply of methods could offer a strong step forward in "mining below the tip of the iceberg" for detecting the "unseen proteome".

  1. Risk assessment of maintenance operations: the analysis of performing task and accident mechanism.

    PubMed

    Carrillo-Castrillo, Jesús A; Rubio-Romero, Juan Carlos; Guadix, Jose; Onieva, Luis

    2015-01-01

    Maintenance operations cover a great number of occupations. Most small and medium-sized enterprises lack the appropriate information to conduct risk assessments of maintenance operations. The objective of this research is to provide a method based on the concepts of task and accident mechanisms for an initial risk assessment by taking into consideration the prevalence and severity of the maintenance accidents reported. Data were gathered from 11,190 reported accidents in maintenance operations in the manufacturing sector of Andalusia from 2003 to 2012. By using a semi-quantitative methodology, likelihood and severity were evaluated based on the actual distribution of accident mechanisms in each of the tasks. Accident mechanisms and tasks were identified by using those variables included in the European Statistics of Accidents at Work methodology. As main results, the estimated risk of the most frequent accident mechanisms identified for each of the analysed tasks is low and the only accident mechanisms with medium risk are accidents when lifting or pushing with physical stress on the musculoskeletal system in tasks involving carrying, and impacts against objects after slipping or stumbling for tasks involving movements. The prioritisation of public preventive actions for the accident mechanisms with a higher estimated risk is highly recommended.

  2. The Analysis of the Contribution of Human Factors to the In-Flight Loss of Control Accidents

    NASA Technical Reports Server (NTRS)

    Ancel, Ersin; Shih, Ann T.

    2012-01-01

    In-flight loss of control (LOC) is currently the leading cause of fatal accidents based on various commercial aircraft accident statistics. As the Next Generation Air Transportation System (NextGen) emerges, new contributing factors leading to LOC are anticipated. The NASA Aviation Safety Program (AvSP), along with other aviation agencies and communities are actively developing safety products to mitigate the LOC risk. This paper discusses the approach used to construct a generic integrated LOC accident framework (LOCAF) model based on a detailed review of LOC accidents over the past two decades. The LOCAF model is comprised of causal factors from the domain of human factors, aircraft system component failures, and atmospheric environment. The multiple interdependent causal factors are expressed in an Object-Oriented Bayesian belief network. In addition to predicting the likelihood of LOC accident occurrence, the system-level integrated LOCAF model is able to evaluate the impact of new safety technology products developed in AvSP. This provides valuable information to decision makers in strategizing NASA's aviation safety technology portfolio. The focus of this paper is on the analysis of human causal factors in the model, including the contributions from flight crew and maintenance workers. The Human Factors Analysis and Classification System (HFACS) taxonomy was used to develop human related causal factors. The preliminary results from the baseline LOCAF model are also presented.

  3. Analysis of traffic accident size for Korean highway using structural equation models.

    PubMed

    Lee, Ju-Yeon; Chung, Jin-Hyuk; Son, Bongsoo

    2008-11-01

    Accident size can be expressed as the number of involved vehicles, the number of damaged vehicles, the number of deaths and/or the number of injured. Accident size is the one of the important indices to measure the level of safety of transportation facilities. Factors such as road geometric condition, driver characteristic and vehicle type may be related to traffic accident size. However, all these factors interact in complicate ways so that the interrelationships among the variables are not easily identified. A structural equation model is adopted to capture the complex relationships among variables because the model can handle complex relationships among endogenous and exogenous variables simultaneously and furthermore it can include latent variables in the model. In this study, we use 2649 accident data occurred on highways in Korea and estimate relationship among exogenous factors and traffic accident size. The model suggests that road factors, driver factors and environment factors are strongly related to the accident size.

  4. System analysis with improved thermo-mechanical fuel rod models for modeling current and advanced LWR materials in accident scenarios

    NASA Astrophysics Data System (ADS)

    Porter, Ian Edward

    A nuclear reactor systems code has the ability to model the system response in an accident scenario based on known initial conditions at the onset of the transient. However, there has been a tendency for these codes to lack the detailed thermo-mechanical fuel rod response models needed for accurate prediction of fuel rod failure. This proposed work will couple today's most widely used steady-state (FRAPCON) and transient (FRAPTRAN) fuel rod models with a systems code TRACE for best-estimate modeling of system response in accident scenarios such as a loss of coolant accident (LOCA). In doing so, code modifications will be made to model gamma heating in LWRs during steady-state and accident conditions and to improve fuel rod thermal/mechanical analysis by allowing axial nodalization of burnup-dependent phenomena such as swelling, cladding creep and oxidation. With the ability to model both burnup-dependent parameters and transient fuel rod response, a fuel dispersal study will be conducted using a hypothetical accident scenario under both PWR and BWR conditions to determine the amount of fuel dispersed under varying conditions. Due to the fuel fragmentation size and internal rod pressure both being dependent on burnup, this analysis will be conducted at beginning, middle and end of cycle to examine the effects that cycle time can play on fuel rod failure and dispersal. Current fuel rod and system codes used by the Nuclear Regulatory Commission (NRC) are compilations of legacy codes with only commonly used light water reactor materials, Uranium Dioxide (UO2), Mixed Oxide (U/PuO 2) and zirconium alloys. However, the events at Fukushima Daiichi and Three Mile Island accident have shown the need for exploration into advanced materials possessing improved accident tolerance. This work looks to further modify the NRC codes to include silicon carbide (SiC), an advanced cladding material proposed by current DOE funded research on accident tolerant fuels (ATF). Several

  5. Multifractal analysis of the 137Cs fallout pattern in Austria resulting from the Chernobyl accident.

    PubMed

    Pausch, G; Bossew, P; Hofmann, W; Steger, F

    1998-06-01

    The cumulative deposition of the 137Cs fallout in Austria resulting from the passage of the Chernobyl cloud has been investigated by applying correlation dimension and hyperbolic frequency distribution methods. For the analysis, a total of 1,881 deposition values were used, which were collected by the Federal Environmental Agency of Austria and the Federal Ministry of Health, representing all available measurements of 137Cs in soil made in Austria after the Chernobyl accident. From these data a hyperbolic exponent for the frequency distribution of 4.0 and a set of fractal correlation dimensions, which decrease from 1.426 +/- 0.022 (for the whole network) to 0.706 +/- 0.047 (for 137Cs values > or = 100 kBq m(-2)), were derived, thus confirming that the fallout pattern can be described as a multifractal.

  6. PTSD symptom severity and psychiatric comorbidity in recent motor vehicle accident victims: a latent class analysis.

    PubMed

    Hruska, Bryce; Irish, Leah A; Pacella, Maria L; Sledjeski, Eve M; Delahanty, Douglas L

    2014-10-01

    We conducted a latent class analysis (LCA) on 249 recent motor vehicle accident (MVA) victims to examine subgroups that differed in posttraumatic stress disorder (PTSD) symptom severity, current major depressive disorder and alcohol/other drug use disorders (MDD/AoDs), gender, and interpersonal trauma history 6-weeks post-MVA. A 4-class model best fit the data with a resilient class displaying asymptomatic PTSD symptom levels/low levels of comorbid disorders; a mild psychopathology class displaying mild PTSD symptom severity and current MDD; a moderate psychopathology class displaying severe PTSD symptom severity and current MDD/AoDs; and a severe psychopathology class displaying extreme PTSD symptom severity and current MDD. Classes also differed with respect to gender composition and history of interpersonal trauma experience. These findings may aid in the development of targeted interventions for recent MVA victims through the identification of subgroups distinguished by different patterns of psychiatric problems experienced 6-weeks post-MVA.

  7. Surgical videos for accident analysis, performance improvement, and complication prevention: time for a surgical black box?

    PubMed

    Gambadauro, Pietro; Magos, Adam

    2012-03-01

    Conventional audit of surgical records through review of surgical results provides useful knowledge but hardly helps identify the technical reasons lying behind specific outcomes or complications. Surgical teams not only need to know that a complication might happen but also how and when it is most likely to happen. Functional awareness is therefore needed to prevent complications, know how to deal with them, and improve overall surgical performance. The authors wish to argue that the systematic recording and reviewing of surgical videos, a "surgical black box," might improve surgical care, help prevent complications, and allow accident analysis. A possible strategy to test this hypothesis is presented and discussed. Recording and reviewing surgical interventions, apart from helping us achieve functional awareness and increasing the safety profile of our performance, allows us also to effectively share our experience with colleagues. The authors believe that those potential implications make this hypothesis worth testing.

  8. Accident safety analysis for 300 Area N Reactor Fuel Fabrication and Storage Facility

    SciTech Connect

    Johnson, D.J.; Brehm, J.R.

    1994-01-01

    The purpose of the accident safety analysis is to identify and analyze a range of credible events, their cause and consequences, and to provide technical justification for the conclusion that uranium billets, fuel assemblies, uranium scrap, and chips and fines drums can be safely stored in the 300 Area N Reactor Fuel Fabrication and Storage Facility, the contaminated equipment, High-Efficiency Air Particulate filters, ductwork, stacks, sewers and sumps can be cleaned (decontaminated) and/or removed, the new concretion process in the 304 Building will be able to operate, without undue risk to the public, employees, or the environment, and limited fuel handling and packaging associated with removal of stored uranium is acceptable.

  9. A comparative analysis of accident risks in fossil, hydro, and nuclear energy chains

    SciTech Connect

    Burgherr, P.; Hirschberg, S.

    2008-07-01

    This study presents a comparative assessment of severe accident risks in the energy sector, based on the historical experience of fossil (coal, oil, natural gas, and LPG (Liquefied Petroleum Gas)) and hydro chains contained in the comprehensive Energy-related Severe Accident Database (ENSAD), as well as Probabilistic Safety Assessment (PSA) for the nuclear chain. Full energy chains were considered because accidents can take place at every stage of the chain. Comparative analyses for the years 1969-2000 included a total of 1870 severe ({>=} 5 fatalities) accidents, amounting to 81,258 fatalities. Although 79.1% of all accidents and 88.9% of associated fatalities occurred in less developed, non-OECD countries, industrialized OECD countries dominated insured losses (78.0%), reflecting their substantially higher insurance density and stricter safety regulations. Aggregated indicators and frequency-consequence (F-N) curves showed that energy-related accident risks in non-OECD countries are distinctly higher than in OECD countries. Hydropower in non-OECD countries and upstream stages within fossil energy chains are most accident-prone. Expected fatality rates are lowest for Western hydropower and nuclear power plants; however, the maximum credible consequences can be very large. Total economic damages due to severe accidents are substantial, but small when compared with natural disasters. Similarly, external costs associated with severe accidents are generally much smaller than monetized damages caused by air pollution.

  10. Final safety analysis report for the Galileo Mission: Volume 2: Book 1, Accident model document

    SciTech Connect

    Not Available

    1988-12-15

    The Accident Model Document (AMD) is the second volume of the three volume Final Safety Analysis Report (FSAR) for the Galileo outer planetary space science mission. This mission employs Radioisotope Thermoelectric Generators (RTGs) as the prime electrical power sources for the spacecraft. Galileo will be launched into Earth orbit using the Space Shuttle and will use the Inertial Upper Stage (IUS) booster to place the spacecraft into an Earth escape trajectory. The RTG's employ silicon-germanium thermoelectric couples to produce electricity from the heat energy that results from the decay of the radioisotope fuel, Plutonium-238, used in the RTG heat source. The heat source configuration used in the RTG's is termed General Purpose Heat Source (GPHS), and the RTG's are designated GPHS-RTGs. The use of radioactive material in these missions necessitates evaluations of the radiological risks that may be encountered by launch complex personnel as well as by the Earth's general population resulting from postulated malfunctions or failures occurring in the mission operations. The FSAR presents the results of a rigorous safety assessment, including substantial analyses and testing, of the launch and deployment of the RTGs for the Galileo mission. This AMD is a summary of the potential accident and failure sequences which might result in fuel release, the analysis and testing methods employed, and the predicted source terms. Each source term consists of a quantity of fuel released, the location of release and the physical characteristics of the fuel released. Each source term has an associated probability of occurrence. 27 figs., 11 tabs.

  11. Probabilistic accident consequence uncertainty analysis: Dispersion and deposition uncertainty assessment, appendices A and B

    SciTech Connect

    Harper, F.T.; Young, M.L.; Miller, L.A.; Hora, S.C.; Lui, C.H.; Goossens, L.H.J.; Cooke, R.M.; Paesler-Sauer, J.; Helton, J.C.

    1995-01-01

    The development of two new probabilistic accident consequence codes, MACCS and COSYMA, completed in 1990, estimate the risks presented by nuclear installations based on postulated frequencies and magnitudes of potential accidents. In 1991, the US Nuclear Regulatory Commission (NRC) and the Commission of the European Communities (CEC) began a joint uncertainty analysis of the two codes. The objective was to develop credible and traceable uncertainty distributions for the input variables of the codes. Expert elicitation, developed independently, was identified as the best technology available for developing a library of uncertainty distributions for the selected consequence parameters. The study was formulated jointly and was limited to the current code models and to physical quantities that could be measured in experiments. To validate the distributions generated for the wet deposition input variables, samples were taken from these distributions and propagated through the wet deposition code model along with the Gaussian plume model (GPM) implemented in the MACCS and COSYMA codes. Resulting distributions closely replicated the aggregated elicited wet deposition distributions. Project teams from the NRC and CEC cooperated successfully to develop and implement a unified process for the elaboration of uncertainty distributions on consequence code input parameters. Formal expert judgment elicitation proved valuable for synthesizing the best available information. Distributions on measurable atmospheric dispersion and deposition parameters were successfully elicited from experts involved in the many phenomenological areas of consequence analysis. This volume is the second of a three-volume document describing the project and contains two appendices describing the rationales for the dispersion and deposition data along with short biographies of the 16 experts who participated in the project.

  12. Probabilistic accident consequence uncertainty analysis: Dispersion and deposition uncertainty assessment, main report

    SciTech Connect

    Harper, F.T.; Young, M.L.; Miller, L.A.; Hora, S.C.; Lui, C.H.; Goossens, L.H.J.; Cooke, R.M.; Paesler-Sauer, J.; Helton, J.C.

    1995-01-01

    The development of two new probabilistic accident consequence codes, MACCS and COSYMA, was completed in 1990. These codes estimate the risks presented by nuclear installations based on postulated frequencies and magnitudes of potential accidents. In 1991, the US Nuclear Regulatory Commission (NRC) and the Commission of the European Communities (CEC) began a joint uncertainty analysis of the two codes. The ultimate objective of the joint effort was to develop credible and traceable uncertainty distributions for the input variables of the codes. Expert elicitation was identified as the best technology available for developing a library of uncertainty distributions for the selected consequence parameters. The study was formulated jointly and was limited to the current code models and to physical quantities that could be measured in experiments. Experts developed their distributions independently. To validate the distributions generated for the wet deposition input variables, samples were taken from these distributions and propagated through the wet deposition code model. Resulting distributions closely replicated the aggregated elicited wet deposition distributions. To validate the distributions generated for the dispersion code input variables, samples from the distributions and propagated through the Gaussian plume model (GPM) implemented in the MACCS and COSYMA codes. Project teams from the NRC and CEC cooperated successfully to develop and implement a unified process for the elaboration of uncertainty distributions on consequence code input parameters. Formal expert judgment elicitation proved valuable for synthesizing the best available information. Distributions on measurable atmospheric dispersion and deposition parameters were successfully elicited from experts involved in the many phenomenological areas of consequence analysis. This volume is the first of a three-volume document describing the project.

  13. Who by accident? The social morphology of car accidents.

    PubMed

    Factor, Roni; Yair, Gad; Mahalel, David

    2010-09-01

    Prior studies in the sociology of accidents have shown that different social groups have different rates of accident involvement. This study extends those studies by implementing Bourdieu's relational perspective of social space to systematically explore the homology between drivers' social characteristics and their involvement in specific types of motor vehicle accident. Using a large database that merges official Israeli road-accident records with socioeconomic data from two censuses, this research maps the social order of road accidents through multiple correspondence analysis. Extending prior studies, the results show that different social groups indeed tend to be involved in motor vehicle accidents of different types and severity. For example, we find that drivers from low socioeconomic backgrounds are overinvolved in severe accidents with fatal outcomes. The new findings reported here shed light on the social regularity of road accidents and expose new facets in the social organization of death.

  14. Defense In-Depth Accident Analysis Evaluation of Tritium Facility Bldgs. 232-H, 233-H, and 234-H

    SciTech Connect

    Blanchard, A.

    1999-05-10

    'The primary purpose of this report is to document a Defense-in-Depth (DID) accident analysis evaluation for Department of Energy (DOE) Savannah River Site (SRS) Tritium Facility Buildings 232-H, 233-H, and 234-H. The purpose of a DID evaluation is to provide a more realistic view of facility radiological risks to the offsite public than the bounding deterministic analysis documented in the Safety Analysis Report, which credits only Safety Class items in the offsite dose evaluation.'

  15. [Analysis of accidents for magnetically induced displacement of the large ferromagnetic material in magnetic resonance systems].

    PubMed

    Yamatani, Yuya; Doi, Tsukasa; Ueyama, Tsuyoshi; Nishiki, Shigeo; Ogura, Akio; Kawamitsu, Hideaki; Tsuchihashi, Toshio; Okuaki, Tomoyuki; Matsuda, Tsuyoshi

    2013-01-01

    To improve magnetic resonance (MR) safety, we surveyed the accidents caused by large ferromagnetic materials brought into MR systems accidentally. We sent a questionnaire to 700 Japanese medical institutions and received 405 valid responses (58%). A total of 97 accidents in 77 institutions were observed and we analyzed them regarding incidental rate, the detail situation and environmental factors. The mean accident rate of each institute was 0.7/100,000 examinations, which was widely distributed (0-25.6/100,000) depending on the institute. In this survey, relatively small institutes with less than 500 beds tend to have these accidents more frequently (p<0.01). The institutes in which daily MR examination counts are more than 10 patients have fewer accidents than those with less than 10 daily examinations. The institutes with 6-10 MR examinations daily have significantly more accidents than that with more than 10 daily MR examinations (p<0.01). The main mental factors of the accidents were considered to be "prejudice" and "carelessness" but some advocate "ignorance." Though we could not find significant reduction in the institutes that have lectures and training for MR safety, we should continue lectures and training for MR safety to reduce accidents due to "ignorance."

  16. Emergency drinking water treatment during source water pollution accidents in China: origin analysis, framework and technologies.

    PubMed

    Zhang, Xiao-Jian; Chen, Chao; Lin, Peng-Fei; Hou, Ai-Xin; Niu, Zhang-Bin; Wang, Jun

    2011-01-01

    China has suffered frequent source water contamination accidents in the past decade, which has resulted in severe consequences to the water supply of millions of residents. The origins of typical cases of contamination are discussed in this paper as well as the emergency response to these accidents. In general, excessive pursuit of rapid industrialization and the unreasonable location of factories are responsible for the increasing frequency of accidental pollution events. Moreover, insufficient attention to environmental protection and rudimentary emergency response capability has exacerbated the consequences of such accidents. These environmental accidents triggered or accelerated the promulgation of stricter environmental protection policy and the shift from economic development mode to a more sustainable direction, which should be regarded as the turning point of environmental protection in China. To guarantee water security, China is trying to establish a rapid and effective emergency response framework, build up the capability of early accident detection, and develop efficient technologies to remove contaminants from water.

  17. A multivariate tobit analysis of highway accident-injury-severity rates.

    PubMed

    Anastasopoulos, Panagiotis Ch; Shankar, Venky N; Haddock, John E; Mannering, Fred L

    2012-03-01

    Relatively recent research has illustrated the potential that tobit regression has in studying factors that affect vehicle accident rates (accidents per distance traveled) on specific roadway segments. Tobit regression has been used because accident rates on specific roadway segments are continuous data that are left-censored at zero (they are censored because accidents may not be observed on all roadway segments during the period over which data are collected). This censoring may arise from a number of sources, one of which being the possibility that less severe crashes may be under-reported and thus may be less likely to appear in crash databases. Traditional tobit-regression analyses have dealt with the overall accident rate (all crashes regardless of injury severity), so the issue of censoring by the severity of crashes has not been addressed. However, a tobit-regression approach that considers accident rates by injury-severity level, such as the rate of no-injury, possible injury and injury accidents per distance traveled (as opposed to all accidents regardless of injury-severity), can potentially provide new insights, and address the possibility that censoring may vary by crash-injury severity. Using five-year data from highways in Washington State, this paper estimates a multivariate tobit model of accident-injury-severity rates that addresses the possibility of differential censoring across injury-severity levels, while also accounting for the possible contemporaneous error correlation resulting from commonly shared unobserved characteristics across roadway segments. The empirical results show that the multivariate tobit model outperforms its univariate counterpart, is practically equivalent to the multivariate negative binomial model, and has the potential to provide a fuller understanding of the factors determining accident-injury-severity rates on specific roadway segments.

  18. Image computing techniques to extrapolate data for dust tracking in case of an experimental accident simulation in a nuclear fusion plant

    NASA Astrophysics Data System (ADS)

    Camplani, M.; Malizia, A.; Gelfusa, M.; Barbato, F.; Antonelli, L.; Poggi, L. A.; Ciparisse, J. F.; Salgado, L.; Richetta, M.; Gaudio, P.

    2016-01-01

    In this paper, a preliminary shadowgraph-based analysis of dust particles re-suspension due to loss of vacuum accident (LOVA) in ITER-like nuclear fusion reactors has been presented. Dust particles are produced through different mechanisms in nuclear fusion devices, one of the main issues is that dust particles are capable of being re-suspended in case of events such as LOVA. Shadowgraph is based on an expanded collimated beam of light emitted by a laser or a lamp that emits light transversely compared to the flow field direction. In the STARDUST facility, the dust moves in the flow, and it causes variations of refractive index that can be detected by using a CCD camera. The STARDUST fast camera setup allows to detect and to track dust particles moving in the vessel and then to obtain information about the velocity field of dust mobilized. In particular, the acquired images are processed such that per each frame the moving dust particles are detected by applying a background subtraction technique based on the mixture of Gaussian algorithm. The obtained foreground masks are eventually filtered with morphological operations. Finally, a multi-object tracking algorithm is used to track the detected particles along the experiment. For each particle, a Kalman filter-based tracker is applied; the particles dynamic is described by taking into account position, velocity, and acceleration as state variable. The results demonstrate that it is possible to obtain dust particles' velocity field during LOVA by automatically processing the data obtained with the shadowgraph approach.

  19. Image computing techniques to extrapolate data for dust tracking in case of an experimental accident simulation in a nuclear fusion plant

    SciTech Connect

    Camplani, M.; Malizia, A.; Gelfusa, M.; Poggi, L. A.; Ciparisse, J. F.; Richetta, M.; Gaudio, P.; Barbato, F.; Antonelli, L.; Salgado, L.

    2016-01-15

    In this paper, a preliminary shadowgraph-based analysis of dust particles re-suspension due to loss of vacuum accident (LOVA) in ITER-like nuclear fusion reactors has been presented. Dust particles are produced through different mechanisms in nuclear fusion devices, one of the main issues is that dust particles are capable of being re-suspended in case of events such as LOVA. Shadowgraph is based on an expanded collimated beam of light emitted by a laser or a lamp that emits light transversely compared to the flow field direction. In the STARDUST facility, the dust moves in the flow, and it causes variations of refractive index that can be detected by using a CCD camera. The STARDUST fast camera setup allows to detect and to track dust particles moving in the vessel and then to obtain information about the velocity field of dust mobilized. In particular, the acquired images are processed such that per each frame the moving dust particles are detected by applying a background subtraction technique based on the mixture of Gaussian algorithm. The obtained foreground masks are eventually filtered with morphological operations. Finally, a multi-object tracking algorithm is used to track the detected particles along the experiment. For each particle, a Kalman filter-based tracker is applied; the particles dynamic is described by taking into account position, velocity, and acceleration as state variable. The results demonstrate that it is possible to obtain dust particles’ velocity field during LOVA by automatically processing the data obtained with the shadowgraph approach.

  20. Image computing techniques to extrapolate data for dust tracking in case of an experimental accident simulation in a nuclear fusion plant.

    PubMed

    Camplani, M; Malizia, A; Gelfusa, M; Barbato, F; Antonelli, L; Poggi, L A; Ciparisse, J F; Salgado, L; Richetta, M; Gaudio, P

    2016-01-01

    In this paper, a preliminary shadowgraph-based analysis of dust particles re-suspension due to loss of vacuum accident (LOVA) in ITER-like nuclear fusion reactors has been presented. Dust particles are produced through different mechanisms in nuclear fusion devices, one of the main issues is that dust particles are capable of being re-suspended in case of events such as LOVA. Shadowgraph is based on an expanded collimated beam of light emitted by a laser or a lamp that emits light transversely compared to the flow field direction. In the STARDUST facility, the dust moves in the flow, and it causes variations of refractive index that can be detected by using a CCD camera. The STARDUST fast camera setup allows to detect and to track dust particles moving in the vessel and then to obtain information about the velocity field of dust mobilized. In particular, the acquired images are processed such that per each frame the moving dust particles are detected by applying a background subtraction technique based on the mixture of Gaussian algorithm. The obtained foreground masks are eventually filtered with morphological operations. Finally, a multi-object tracking algorithm is used to track the detected particles along the experiment. For each particle, a Kalman filter-based tracker is applied; the particles dynamic is described by taking into account position, velocity, and acceleration as state variable. The results demonstrate that it is possible to obtain dust particles' velocity field during LOVA by automatically processing the data obtained with the shadowgraph approach.

  1. LHC Olympics: Advanced Analysis Techniques

    NASA Astrophysics Data System (ADS)

    Armour, Kyle; Larkoski, Andrew; Gray, Amanda; Ventura, Dan; Walsh, Jon; Schabinger, Rob

    2006-05-01

    The LHC Olympics is a series of workshop aimed at encouraging theorists and experimentalists to prepare for the soon-to-be-online Large Hadron Collider in Geneva, Switzerland. One aspect of the LHC Olympics program consists of the study of simulated data sets which represent various possible new physics signals as they would be seen in LHC detectors. Through this exercise, LHC Olympians learn the phenomenology of possible new physics models and gain experience in analyzing LHC data. Additionally, the LHC Olympics encourages discussion between theorists and experimentalists, and through this collaboration new techniques could be developed. The University of Washington LHC Olympics group consists of several first-year graduate and senior undergraduate students, in both theoretical and experimental particle physics. Presented here is a discussion of some of the more advanced techniques used and the recent results of one such LHC Olympics study.

  2. Accident analysis and control options in support of the sludge water system safety analysis

    SciTech Connect

    HEY, B.E.

    2003-01-16

    A hazards analysis was initiated for the SWS in July 2001 (SNF-8626, K Basin Sludge and Water System Preliminary Hazard Analysis) and updated in December 2001 (SNF-10020 Rev. 0, Hazard Evaluation for KE Sludge and Water System - Project A16) based on conceptual design information for the Sludge Retrieval System (SRS) and 60% design information for the cask and container. SNF-10020 was again revised in September 2002 to incorporate new hazards identified from final design information and from a What-if/Checklist evaluation of operational steps. The process hazards, controls, and qualitative consequence and frequency estimates taken from these efforts have been incorporated into Revision 5 of HNF-3960, K Basins Hazards Analysis. The hazards identification process documented in the above referenced reports utilized standard industrial safety techniques (AIChE 1992, Guidelines for Hazard Evaluation Procedures) to systematically guide several interdisciplinary teams through the system using a pre-established set of process parameters (e.g., flow, temperature, pressure) and guide words (e.g., high, low, more, less). The teams generally included representation from the U.S. Department of Energy (DOE), K Basins Nuclear Safety, T Plant Nuclear Safety, K Basin Industrial Safety, fire protection, project engineering, operations, and facility engineering.

  3. Analysis of fission product revaporization in a BWR Reactor Coolant System during a station blackout accident

    SciTech Connect

    Yang, J.W.; Schmidt, E.; Cazzoli, E.; Khatib-Rahbar, M.

    1988-01-01

    This paper presents an analysis of fission product revaporization from the Reactor Coolant System (RCS) following the Reactor Pressure Vessel (RPV) failure. The station blackout accident in a BWR Mark I Power Plant was considered. The TRAPMELT3 models for vaporization, chemisorption, and the decay heating of RCS structures and gases were used and extended beyond the RPV failure in the analysis. The RCS flow models based on the density-difference or pressure-difference between the RCS and containment pedestal region were developed to estimate the RCS outflow which carries the revaporized fission product to the containment. A computer code called REVAP was developed for the analysis. The REVAP code was incorporated with the MARCH, TRAPMELT3 and NAUA codes from the Source Term Code Package (STCP) to estimate the impact of revaporization on environmental release. The results show that the thermal-hydraulic conditions between the RCS and the pedestal region are important factors in determining the magnitude of revaporization and subsequent release of the volatile fission product into the environment. 6 refs., 8 figs.

  4. Analysis of the Loss of Forced Reactor Coolant Flow Accident in SMART using RETRAN-03/INT

    SciTech Connect

    Kim, Tae-Wan; Suh, Kune-Yull; Lee, Un-Chul; Park, Goon-Cherl; Kim, Jae-Hak

    2002-07-01

    Small and medium integral type nuclear reactors are getting much attention for the peaceful use of nuclear energy in non-electric area such as district heating, seawater desalination and ship propulsion. An integral type nuclear co-generation reactor, SMART(System-integrated Modular Advanced ReacTor, 330 MWt), has been developed by KAERI (Korea Atomic Energy Research Institute) since 1996. In this study, the safety analysis for SMART using modified RETRAN-03 code whose name is RETRAN-03/INT is performed to examine the applicability of RETRAN-03/INT code. For the safety analysis of integral reactor with helical-coiled steam generators, RETRAN-03 code has been modified and verified using experimental results. New heat transfer coefficients are added for helical-coiled steam generator. And, the heat transfer model for steam generator is modified due to the different primary and secondary side heat flow from U-tube type steam generator. The loss of forced reactor coolant flow accident is selected for safety analysis in this study. Also it is considered as a single failure that one of three trains of passive residual heat removal system is failed. The results from MARS/SMR code and RETRAN-03/INT code are compared. (authors)

  5. TRACE/PARCS Core Modeling of a BWR/5 for Accident Analysis of ATWS Events

    SciTech Connect

    Cuadra A.; Baek J.; Cheng, L.; Aronson, A.; Diamond, D.; Yarsky, P.

    2013-11-10

    The TRACE/PARCS computational package [1, 2] isdesigned to be applicable to the analysis of light water reactor operational transients and accidents where the coupling between the neutron kinetics (PARCS) and the thermal-hydraulics and thermal-mechanics (TRACE) is important. TRACE/PARCS has been assessed for itsapplicability to anticipated transients without scram(ATWS) [3]. The challenge, addressed in this study, is to develop a sufficiently rigorous input model that would be acceptable for use in ATWS analysis. Two types of ATWS events were of interest, a turbine trip and a closure of main steam isolation valves (MSIVs). In the first type, initiated by turbine trip, the concern is that the core will become unstable and large power oscillations will occur. In the second type,initiated by MSIV closure,, the concern is the amount of energy being placed into containment and the resulting emergency depressurization. Two separate TRACE/PARCS models of a BWR/5 were developed to analyze these ATWS events at MELLLA+ (maximum extended load line limit plus)operating conditions. One model [4] was used for analysis of ATWS events leading to instability (ATWS-I);the other [5] for ATWS events leading to emergency depressurization (ATWS-ED). Both models included a large portion of the nuclear steam supply system and controls, and a detailed core model, presented henceforth.

  6. Analysis of Surface Water Pollution Accidents in China: Characteristics and Lessons for Risk Management

    NASA Astrophysics Data System (ADS)

    Yao, Hong; Zhang, Tongzhu; Liu, Bo; Lu, Feng; Fang, Shurong; You, Zhen

    2016-04-01

    Understanding historical accidents is important for accident prevention and risk mitigation; however, there are no public databases of pollution accidents in China, and no detailed information regarding such incidents is readily available. Thus, 653 representative cases of surface water pollution accidents in China were identified and described as a function of time, location, materials involved, origin, and causes. The severity and other features of the accidents, frequency and quantities of chemicals involved, frequency and number of people poisoned, frequency and number of people affected, frequency and time for which pollution lasted, and frequency and length of pollution zone were effectively used to value and estimate the accumulated probabilities. The probabilities of occurrences of various types based on origin and causes were also summarized based on these observations. The following conclusions can be drawn from these analyses: (1) There was a high proportion of accidents involving multi-district boundary regions and drinking water crises, indicating that more attention should be paid to environmental risk prevention and the mitigation of such incidents. (2) A high proportion of accidents originated from small-sized chemical plants, indicating that these types of enterprises should be considered during policy making. (3) The most common cause (49.8 % of the total) was intentional acts (illegal discharge); accordingly, efforts to increase environmental consciousness in China should be enhanced.

  7. Analysis of Surface Water Pollution Accidents in China: Characteristics and Lessons for Risk Management.

    PubMed

    Yao, Hong; Zhang, Tongzhu; Liu, Bo; Lu, Feng; Fang, Shurong; You, Zhen

    2016-04-01

    Understanding historical accidents is important for accident prevention and risk mitigation; however, there are no public databases of pollution accidents in China, and no detailed information regarding such incidents is readily available. Thus, 653 representative cases of surface water pollution accidents in China were identified and described as a function of time, location, materials involved, origin, and causes. The severity and other features of the accidents, frequency and quantities of chemicals involved, frequency and number of people poisoned, frequency and number of people affected, frequency and time for which pollution lasted, and frequency and length of pollution zone were effectively used to value and estimate the accumulated probabilities. The probabilities of occurrences of various types based on origin and causes were also summarized based on these observations. The following conclusions can be drawn from these analyses: (1) There was a high proportion of accidents involving multi-district boundary regions and drinking water crises, indicating that more attention should be paid to environmental risk prevention and the mitigation of such incidents. (2) A high proportion of accidents originated from small-sized chemical plants, indicating that these types of enterprises should be considered during policy making. (3) The most common cause (49.8% of the total) was intentional acts (illegal discharge); accordingly, efforts to increase environmental consciousness in China should be enhanced.

  8. The effect of gamma-ray transport on afterheat calculations for accident analysis

    SciTech Connect

    Reyes, S.; Latkowski, J.F.; Sanz, J.

    2000-05-01

    Radioactive afterheat is an important source term for the release of radionuclides in fusion systems under accident conditions. Heat transfer calculations are used to determine time-temperature histories in regions of interest, but the true source term needs to be the effective afterheat, which considers the transport of penetrating gamma rays. Without consideration of photon transport, accident temperatures may be overestimated in others. The importance of this effect is demonstrated for a simple, one-dimensional problem. The significance of this effect depends strongly on the accident scenario being analyzed.

  9. Digital techniques for ULF wave polarization analysis

    NASA Technical Reports Server (NTRS)

    Arthur, C. W.

    1979-01-01

    Digital power spectral and wave polarization analysis are powerful techniques for studying ULF waves in the earth's magnetosphere. Four different techniques for using the spectral matrix to perform such an analysis have been presented in the literature. Three of these techniques are similar in that they require transformation of the spectral matrix to the principal axis system prior to performing the polarization analysis. The differences in the three techniques lie in the manner in which determine this transformation. A comparative study of these three techniques using both simulated and real data has shown them to be approximately equal in quality of performance. The fourth technique does not require transformation of the spectral matrix. Rather, it uses the measured spectral matrix and state vectors for a desired wave type to design a polarization detector function in the frequency domain. The design of various detector functions and their application to both simulated and real data will be presented.

  10. Overview of the Aerothermodynamics Analysis Conducted in Support of the STS-107 Accident Investigation

    NASA Technical Reports Server (NTRS)

    Campbell, Charles H.

    2004-01-01

    A graphic presentation of the aerothermodynamics analysis conducted in support of the STS-107 accident investigation. Investigation efforts were conducted as part of an integrated AATS team (Aero, Aerothermal, Thermal, Stress) directed by OVEWG. Graphics presented are: STS-107 Entry trajectory and timeline (1st off-nominal event to Post-LOS); Indications from OI telemetry data; Aero/aerothermo/thermal analysis process; Selected STS-107 side fuselage/OMS pod off-nominal temperatures; Leading edge structural subsystem; Relevant forensics evidence; External aerothermal environments; STS-107 Pre-entry EOM3 heating profile; Surface heating and temperatures; Orbiter wing leading edge damage survey; Internal aerothermal environments; Orbiter wing CAD model; Aerodynamic flight reconstruction; Chronology of aerodynamic/aerothermoydynamic contributions; Acreage TPS tile damage; Larger OML perturbations; Missing RCC panel(s); Localized damage to RCC panel/missing T-seal; RCC breach with flow ingestion; and Aero-aerothermal closure. NAIT served as the interface between the CAIB and NASA investigation teams; and CAIB requests for study were addressed.

  11. Development of NASA's Accident Precursor Analysis Process Through Application on the Space Shuttle Orbiter

    NASA Technical Reports Server (NTRS)

    Maggio, Gaspare; Groen, Frank; Hamlin, Teri; Youngblood, Robert

    2010-01-01

    Accident Precursor Analysis (APA) serves as the bridge between existing risk modeling activities, which are often based on historical or generic failure statistics, and system anomalies, which provide crucial information about the failure mechanisms that are actually operative in the system. APA docs more than simply track experience: it systematically evaluates experience, looking for under-appreciated risks that may warrant changes to design or operational practice. This paper presents the pilot application of the NASA APA process to Space Shuttle Orbiter systems. In this effort, the working sessions conducted at Johnson Space Center (JSC) piloted the APA process developed by Information Systems Laboratories (ISL) over the last two years under the auspices of NASA's Office of Safety & Mission Assurance, with the assistance of the Safety & Mission Assurance (S&MA) Shuttle & Exploration Analysis Branch. This process is built around facilitated working sessions involving diverse system experts. One important aspect of this particular APA process is its focus on understanding the physical mechanism responsible for an operational anomaly, followed by evaluation of the risk significance of the observed anomaly as well as consideration of generalizations of the underlying mechanism to other contexts. Model completeness will probably always be an issue, but this process tries to leverage operating experience to the extent possible in order to address completeness issues before a catastrophe occurs.

  12. Homicide or accident off the coast of Florida: trauma analysis of mutilated human remains.

    PubMed

    Stubblefield, P R

    1999-07-01

    In the many years Dr. William R. Maples served as a forensic anthropologist, he saw diverse sources of trauma presented in the victims of violent crime, accident and suicide in the state of Florida. In 1996 the District 18 Medical Examiner's Office of Florida requested the assistance of Dr. Maples in the analysis of human remains recovered by the U.S. Coast Guard. The deceased was in an advanced state of decomposition characterized by skin slippage and discoloration. The torso bore multiple lacerations, including nearly parallel lacerations in the skin of the back. Specimens were carefully macerated and the fractures reconstructed. The skeletal trauma was caused by a device capable of delivering robust cuts and blunt trauma in linear paths, as is consistent with propeller trauma. Unusual in this case were blows to the ventral and dorsal surfaces of the body. Based on the anthropological analysis and interviews with the family of the deceased, the F.B.I. proceeded with the case as a homicide investigation.

  13. Data analysis techniques: Spectral processing

    NASA Technical Reports Server (NTRS)

    Strauch, R. G.

    1983-01-01

    The individual steps in the data processing scheme applied to most radars used for wind sounding are analyzed. This processing method uses spectral analysis and assumes a pulse Doppler radar. Improvement in the signal to noise ratio of some radars is discussed.

  14. Injury Prevention in Aircraft Crashes: Investigative Techniques and Applications (la Prevention des lesions lors des accidents d’ avions: les techniques d’investigation et leurs applications)

    DTIC Science & Technology

    1998-02-01

    approximately parallel to the long axis of the spine. Similarly, a typical finding in light-aircraft accidents involves blunt trauma applied to...produce minor superficial trauma such as bruises and abrasions which do not incapacitate, injurious forces result in moderate to severe trauma ...spleen can occur from blunt trauma to any part of the abdomen. Studies to delineate tolerance levels to non-penetrating abdominal trauma are limited

  15. Alternate Spectrometric Oil Analysis Techniques

    DTIC Science & Technology

    1992-04-01

    Spectrometric Analysis 75 V. CONCLUSIONS 81 VI. RECOMMENDAT IONS 85 APPENDIX A MICROFILTRATION TEST RIG DATA 87 APPENDIX B MEMBRANE FILTRATION TEST DATA 135...SPECTROETERS 9 2. DESCRIPTION OF MICROFILTRATION TEST RIG FLUIDS 12 3. DESCRIPTION OF SAMPLES USED FOR 3 MICRON PORE SIZE MEMBRANE FILTRATION 15 4... microfiltration , 10-20 ml portions of the used oil samples were passed through a 3 Pm Nucleopore membrane filter. 14 TABLE 3 DESCRIPTION OF SAMPLES USED

  16. Lower head creep rupture failure analysis associated with alternative accident sequences of the Three Mile Island Unit 2

    SciTech Connect

    Sang Lung, Chan

    2004-07-01

    The objective of this lower head creep rupture analysis is to assess the current version of MELCOR 1.8.5-RG against SCDAP/RELAP5 MOD 3.3kz. The purpose of this assessment is to investigate the current MELCOR in-vessel core damage progression phenomena including the model for the formation of a molten pool. The model for stratified molten pool natural heat transfer will be included in the next MELCOR release. Presently, MELCOR excludes the gap heat-transfer model for the cooling associated with the narrow gap between the debris and the lower head vessel wall. All these phenomenological models are already treated in SCDAP/RELAP5 using the COUPLE code to model the heat transfer of the relocated debris with the lower head based on a two-dimensional finite-element-method. The assessment should determine if current MELCOR capabilities adequately cover core degradation phenomena appropriate for the consolidated MELCOR code. Inclusion of these features should bring MELCOR much closer to a state of parity with SCDAP/RELAP5 and is a currently underway element in the MELCOR code consolidation effort. This assessment deals with the following analysis of the Three Mile Island Unit 2 (TMI-2) alternative accident sequences. The TMI-2 alternative accident sequence-1 includes the continuation of the base case of the TMI-2 accident with the Reactor Coolant Pumps (RCP) tripped, and the High Pressure Injection System (HPIS) throttled after approximately 6000 s accident time, while in the TMI-2 alternative accident sequence-2, the reactor coolant pumps is tripped after 6000 s and the HPIS is activated after 12,012 s. The lower head temperature distributions calculated with SCDAP/RELAP5 are visualized and animated with open source visualization freeware 'OpenDX'. (author)

  17. Analysis of criticality accident alarm system coverage in the X-700, X-705, and X-720 facilities at the Portsmouth Gaseous Diffusion plant

    SciTech Connect

    Skapik, C.W.; Dobelbower, M.C.; Woollard, J.E.

    1995-12-01

    Additional services for the uranium enrichment cascade process, such as maintenance and decontamination operations, are provided by several ancillary facilities at the PORTS site. These facilities include the X-700 Maintenance Facility, the X-705 Decontamination Facility, and the X-720 Maintenance and Stores Facility. As uranium operations are performed within these facilities, the potential for a criticality accident exists. In the event of a criticality accident within one of these facilities at PORTS, a Criticality Accident Alarm System (CAAS) is in place to detect the criticality accident and sound an alarm. In this report, an analysis was performed to provide verification that the existing CAAS at PORTS provides complete criticality accident coverage in the X-700, X-705, and X-720 facilities. The analysis has determined that the X-705 and X-720 facilities have complete CAAS coverage; the X-700 facility has not been shown to have complete CAAS coverage at this time.

  18. Analysis of labour accidents in tunnel construction and introduction of prevention measures

    PubMed Central

    KIKKAWA, Naotaka; ITOH, Kazuya; HORI, Tomohito; TOYOSAWA, Yasuo; ORENSE, Rolando P.

    2015-01-01

    At present, almost all mountain tunnels in Japan are excavated and constructed utilizing the New Austrian Tunneling Method (NATM), which was advocated by Prof. Rabcewicz of Austria in 1964. In Japan, this method has been applied to tunnel construction since around 1978, after which there has been a subsequent decrease in the number of casualties during tunnel construction. However, there is still a relatively high incidence of labour accidents during tunnel construction when compared to incidence rates in the construction industry in general. During tunnel construction, rock fall events at the cutting face are a particularly characteristic of the type of accident that occurs. In this study, we analysed labour accidents that possess the characteristics of a rock fall event at a work site. We also introduced accident prevention measures against rock fall events. PMID:26027707

  19. Traffic Analysis and Road Accidents: A Case Study of Hyderabad using GIS

    NASA Astrophysics Data System (ADS)

    Bhagyaiah, M.; Shrinagesh, B.

    2014-06-01

    Globalization has impacted many developing countries across the world. India is one such country, which benefited the most. Increased, economic activity raised the consumption levels of the people across the country. This created scope for increase in travel and transportation. The increase in the vehicles since last 10 years has put lot of pressure on the existing roads and ultimately resulting in road accidents. It is estimated that since 2001 there is an increase of 202 percent of two wheeler and 286 percent of four wheeler vehicles with no road expansion. Motor vehicle crashes are a common cause of death, disability and demand for emergency medical care. Globally, more than 1 million people die each year from traffic crashes and about 20-50 million are injured or permanently disabled. There has been increasing trend in road accidents in Hyderabad over a few years. GIS helps in locating the accident hotspots and also in analyzing the trend of road accidents in Hyderabad.

  20. Real Time Data Analysis Techniques

    NASA Astrophysics Data System (ADS)

    Silberberg, George G.

    1983-03-01

    By the early 1970s, classical photo-optical range instrumentation technology (as a means of gathering weapons' system performance data) had become a costly and inefficient process. Film costs were increasing due to soaring silver prices. Time required to process, read, and produce optical data was becoming unacceptable as a means of supporting weapon system development programs. NWC investigated the feasibility of utilizing Closed Circuit Television (CCTV) technology as an alternative solution for providing optical data. In 1978 a program entitled Metric Video (measurements from video images) was formulated at the Naval Weapons Center, China Lake, California. The purpose of this program was to provide timely data, to reduce the number of operating personnel, and to lower data acquisition costs. Some of the task elements for this program included a near real-time vector miss-distance system, a weapons scoring system, a velocity measuring system, a time-space position system, and a system to replace film cameras for gathering real-time engineering sequential data. These task elements and the development of special hardware and techniques to achieve real-time data will be discussed briefly in this paper.

  1. GIS based analysis of Intercity Fatal Road Traffic Accidents in Iran.

    PubMed

    Alizadeh, A; Zare, M; Darparesh, M; Mohseni, S; Soleimani-Ahmadi, M

    2015-01-01

    Road traffic accidents including intercity car traffic accidents (ICTAs) are among the most important causes of morbidity and mortality due to the growing number of vehicles, risky behaviors, and changes in lifestyle of the general population. A sound knowledge of the geographical distribution of car traffic accidents can be considered as an approach towards the accident causation and it can be used as an administrative tool in allocating the sources for traffic accidents prevention. This study was conducted to investigate the geographical distribution and the time trend of fatal intercity car traffic accidents in Iran. To conduct this descriptive study, all Iranian intercity road traffic mortality data were obtained from the Police reports in the Statistical Yearbook of the Governor's Budget and Planning. The obtained data were for 17 complete Iranian calendar years from March 1997 to March 2012. The incidence rate (IR) of fatal ICTAs for each year was calculated as the total number of fatal ICTAs in every 100000 population in specified time intervals. Figures and maps indicating the trends and geographical distribution of fatal ICTAs were prepared while using Microsoft Excel and ArcGis9.2 software. The number of fatal car accidents showed a general increasing trend from 3000 in 1996 to 13500 in 2012. The incidence of fatal intercity car accidents has changed from six in 100000 population in 1996 to 18 in 100000 population in 2012. GIS based data showed that the incidence rate of ICTAs in different provinces of Iran was very divergent. The highest incidence of fatal ICTAs was in Semnan province (IR= 35.2), followed by North Khorasan (IR=22.7), and South Khorasan (IR=22). The least incidence of fatal ICTAs was in Tehran province (IR=2.4) followed by Khozestan (IR=6.5), and Eastern Azarbayejan (IR=6.6). The compensation cost of fatal ICTAs also showed an increasing trend during the studied period. Since an increasing amount of money was being paid yearly for the car

  2. GIS based analysis of Intercity Fatal Road Traffic Accidents in Iran

    PubMed Central

    Alizadeh, A; Zare, M; Darparesh, M; Mohseni, S; Soleimani-Ahmadi, M

    2015-01-01

    Road traffic accidents including intercity car traffic accidents (ICTAs) are among the most important causes of morbidity and mortality due to the growing number of vehicles, risky behaviors, and changes in lifestyle of the general population. A sound knowledge of the geographical distribution of car traffic accidents can be considered as an approach towards the accident causation and it can be used as an administrative tool in allocating the sources for traffic accidents prevention. This study was conducted to investigate the geographical distribution and the time trend of fatal intercity car traffic accidents in Iran. To conduct this descriptive study, all Iranian intercity road traffic mortality data were obtained from the Police reports in the Statistical Yearbook of the Governor’s Budget and Planning. The obtained data were for 17 complete Iranian calendar years from March 1997 to March 2012. The incidence rate (IR) of fatal ICTAs for each year was calculated as the total number of fatal ICTAs in every 100000 population in specified time intervals. Figures and maps indicating the trends and geographical distribution of fatal ICTAs were prepared while using Microsoft Excel and ArcGis9.2 software. The number of fatal car accidents showed a general increasing trend from 3000 in 1996 to 13500 in 2012. The incidence of fatal intercity car accidents has changed from six in 100000 population in 1996 to 18 in 100000 population in 2012. GIS based data showed that the incidence rate of ICTAs in different provinces of Iran was very divergent. The highest incidence of fatal ICTAs was in Semnan province (IR= 35.2), followed by North Khorasan (IR=22.7), and South Khorasan (IR=22). The least incidence of fatal ICTAs was in Tehran province (IR=2.4) followed by Khozestan (IR=6.5), and Eastern Azarbayejan (IR=6.6). The compensation cost of fatal ICTAs also showed an increasing trend during the studied period. Since an increasing amount of money was being paid yearly for the

  3. Innovative Techniques Simplify Vibration Analysis

    NASA Technical Reports Server (NTRS)

    2010-01-01

    In the early years of development, Marshall Space Flight Center engineers encountered challenges related to components in the space shuttle main engine. To assess the problems, they evaluated the effects of vibration and oscillation. To enhance the method of vibration signal analysis, Marshall awarded Small Business Innovation Research (SBIR) contracts to AI Signal Research, Inc. (ASRI), in Huntsville, Alabama. ASRI developed a software package called PC-SIGNAL that NASA now employs on a daily basis, and in 2009, the PKP-Module won Marshall s Software of the Year award. The technology is also used in many industries: aircraft and helicopter, rocket engine manufacturing, transportation, and nuclear power."

  4. Highway accident severities and the mixed logit model: an exploratory empirical analysis.

    PubMed

    Milton, John C; Shankar, Venky N; Mannering, Fred L

    2008-01-01

    Many transportation agencies use accident frequencies, and statistical models of accidents frequencies, as a basis for prioritizing highway safety improvements. However, the use of accident severities in safety programming has been often been limited to the locational assessment of accident fatalities, with little or no emphasis being placed on the full severity distribution of accidents (property damage only, possible injury, injury)-which is needed to fully assess the benefits of competing safety-improvement projects. In this paper we demonstrate a modeling approach that can be used to better understand the injury-severity distributions of accidents on highway segments, and the effect that traffic, highway and weather characteristics have on these distributions. The approach we use allows for the possibility that estimated model parameters can vary randomly across roadway segments to account for unobserved effects potentially relating to roadway characteristics, environmental factors, and driver behavior. Using highway-injury data from Washington State, a mixed (random parameters) logit model is estimated. Estimation findings indicate that volume-related variables such as average daily traffic per lane, average daily truck traffic, truck percentage, interchanges per mile and weather effects such as snowfall are best modeled as random-parameters-while roadway characteristics such as the number of horizontal curves, number of grade breaks per mile and pavement friction are best modeled as fixed parameters. Our results show that the mixed logit model has considerable promise as a methodological tool in highway safety programming.

  5. Biomechanical analysis of occupant kinematics in rollover motor vehicle accidents: dynamic spit test.

    PubMed

    Sances, Anthony; Kumaresan, Srirangam; Clarke, Richard; Herbst, Brian; Meyer, Steve

    2005-01-01

    A better understanding of occupant kinematics in rollover accidents helps to advance biomechanical knowledge and to enhance the safety features of motor vehicles. While many rollover accident simulation studies have adopted the static approach to delineate the occupant kinematics in rollover accidents, very few studies have attempted the dynamic approach. The present work was designed to study the biomechanics of restrained occupants during rollover accidents using the steady-state dynamic spit test and to address the importance of keeping the lap belt fastened. Experimental tests were conducted using an anthropometric 50% Hybrid III dummy in a vehicle. The vehicle was rotated at 180 degrees/second and the dummy was restrained using a standard three-point restraint system. The lap belt of the dummy was fastened either by using the cinching latch plate or by locking the retractor. Three configurations of shoulder belt harness were simulated: shoulder belt loose on chest with cinch plate, shoulder belt under the left arm and shoulder belt behind the chest. In all tests, the dummy stayed within the confinement of the vehicle indicating that the securely fastened lap belt holds the dummy with dynamic movement of 3 1/2" to 4". The results show that occupant movement in rollover accidents is least affected by various shoulder harness positions with a securely fastened lap belt. The present study forms a first step in delineating the biomechanics of occupants in rollover accidents.

  6. Comparing Techniques for Certified Static Analysis

    NASA Technical Reports Server (NTRS)

    Cachera, David; Pichardie, David

    2009-01-01

    A certified static analysis is an analysis whose semantic validity has been formally proved correct with a proof assistant. The recent increasing interest in using proof assistants for mechanizing programming language metatheory has given rise to several approaches for certification of static analysis. We propose a panorama of these techniques and compare their respective strengths and weaknesses.

  7. Identification of Behavior Based Safety by Using Traffic Light Analysis to Reduce Accidents

    NASA Astrophysics Data System (ADS)

    Mansur, A.; Nasution, M. I.

    2016-01-01

    This work present the safety assessment of a case study and describes an important area within the field production in oil and gas industry, namely behavior based safety (BBS). The company set a rigorous BBS and its intervention program that implemented and deployed continually. In this case, observers requested to have discussion and spread a number of determined questions related with work behavior to the workers during observation. Appraisal of Traffic Light Analysis (TLA) as one tools of risk assessment used to determine the estimated score of BBS questionnaire. Standardization of TLA appraisal in this study are based on Regulation of Minister of Labor and Occupational Safety and Health No:PER.05/MEN/1996. The result shown that there are some points under 84%, which categorized in yellow category and should corrected immediately by company to prevent existing bad behavior of workers. The application of BBS expected to increase the safety performance at work time-by-time and effective in reducing accidents.

  8. THERMAL ANALYSIS OF A 9975 PACKAGE IN A FACILITY FIRE ACCIDENT

    SciTech Connect

    Gupta, N.

    2011-02-14

    Surplus plutonium bearing materials in the U.S. Department of Energy (DOE) complex are stored in the 3013 containers that are designed to meet the requirements of the DOE standard DOE-STD-3013. The 3013 containers are in turn packaged inside 9975 packages that are designed to meet the NRC 10 CFR Part 71 regulatory requirements for transporting the Type B fissile materials across the DOE complex. The design requirements for the hypothetical accident conditions (HAC) involving a fire are given in 10 CFR 71.73. The 9975 packages are stored at the DOE Savannah River Site in the K-Area Material Storage (KAMS) facility for long term of up to 50 years. The design requirements for safe storage in KAMS facility containing multiple sources of combustible materials are far more challenging than the HAC requirements in 10 CFR 71.73. While the 10 CFR 71.73 postulates an HAC fire of 1475 F and 30 minutes duration, the facility fire calls for a fire of 1500 F and 86 duration. This paper describes a methodology and the analysis results that meet the design limits of the 9975 component and demonstrate the robustness of the 9975 package.

  9. Sensitivity analysis of a ship accident at a deep-ocean site in the northwest Atlantic

    SciTech Connect

    Kaplan, M.F.

    1985-04-01

    This report presents the results of a sensitivity analysis for an HLW ship accident occurring in the Nares Abyssal Plain in the northwestern Atlantic. Waste form release rate, canister lifetime and sorption in the water column (partition coefficients) were varied. Also investigated were the relative importance of the dose from the food chain and from seaweed in the diet. Peak individual doses and integrated collective doses for populations were the units of comparison. In accordance with international guidelines on radiological protection, the comparisons of different options were carried out over ''all time''; the study uses a million-year time frame. Partition coefficients have the most pronounced effect on collective dose of the parameters studied. Variations in partition coefficients affect the shape of the collective dose curve over the entire time frame. Peak individual doses decrease markedly when the value for the sorption of americium is increased, but show no increase when less sorption is assumed. Waste form release rates and canister lifetimes affect collective doses only in periods prior to 20,000 years. Hence, comparisons of these options need not be carried out beyond 20,000 years. Waste from release rates below 10/sup -3//yr (nominal value) affect individual doses in a linear manner, i.e., an order-of-magnitude reduction in release rate leads to an order-of-magnitude reduction in peak individual dose. Little reduction in peak individual doses is seen with canister lifetimes extended beyond the nominal 100 years. 32 refs., 14 figs., 16 tabs.

  10. Routes to failure: analysis of 41 civil aviation accidents from the Republic of China using the human factors analysis and classification system.

    PubMed

    Li, Wen-Chin; Harris, Don; Yu, Chung-San

    2008-03-01

    The human factors analysis and classification system (HFACS) is based upon Reason's organizational model of human error. HFACS was developed as an analytical framework for the investigation of the role of human error in aviation accidents, however, there is little empirical work formally describing the relationship between the components in the model. This research analyses 41 civil aviation accidents occurring to aircraft registered in the Republic of China (ROC) between 1999 and 2006 using the HFACS framework. The results show statistically significant relationships between errors at the operational level and organizational inadequacies at both the immediately adjacent level (preconditions for unsafe acts) and higher levels in the organization (unsafe supervision and organizational influences). The pattern of the 'routes to failure' observed in the data from this analysis of civil aircraft accidents show great similarities to that observed in the analysis of military accidents. This research lends further support to Reason's model that suggests that active failures are promoted by latent conditions in the organization. Statistical relationships linking fallible decisions in upper management levels were found to directly affect supervisory practices, thereby creating the psychological preconditions for unsafe acts and hence indirectly impairing the performance of pilots, ultimately leading to accidents.

  11. Revealing the association between cerebrovascular accidents and ambient temperature: a meta-analysis

    NASA Astrophysics Data System (ADS)

    Zorrilla-Vaca, Andrés; Healy, Ryan Jacob; Silva-Medina, Melissa M.

    2016-10-01

    The association between cerebrovascular accidents (CVA) and weather has been described across several studies showing multiple conflicting results. In this paper, we aim to conduct a meta-analysis to further clarify this association, as well as to find the potential sources of heterogeneity. PubMed, EMBASE, and Google Scholar were searched from inception through 2015, for articles analyzing the correlation between the incidence of CVA and temperature. A pooled effect size (ES) was estimated using random effects model and expressed as absolute values. Subgroup analyses by type of CVA were also performed. Heterogeneity and influence of covariates—including geographic latitude of the study site, male percentage, average temperature, and time interval—were assessed by meta-regression analysis. Twenty-six articles underwent full data extraction and scoring. A total of 19,736 subjects with CVA from 12 different countries were included and grouped as ischemic strokes (IS; n = 14,199), intracerebral hemorrhages (ICH; n = 3798), and subarachnoid hemorrhages (SAH; n = 1739). Lower ambient temperature was significantly associated with increase in incidence of overall CVA when using unadjusted (pooled ES = 0.23, P < 0.001) and adjusted data (pooled ES = 0.03, P = 0.003). Subgroup analyses showed that lower temperature has higher impact on the incidence of ICH (pooled ES = 0.34, P < 0.001), than that of IS (pooled ES = 0.22, P < 0.001) and SAH (pooled ES = 0.11, P = 0.012). In meta-regression analysis, the geographic latitude of the study site was the most influencing factor on this association (Z-score = 8.68). Synthesis of the existing data provides evidence supporting that a lower ambient temperature increases the incidence of CVA. Further population-based studies conducted at negative latitudes are needed to clarify the influence of this factor.

  12. Ion beam analysis techniques in interdisciplinary applications

    SciTech Connect

    Respaldiza, Miguel A.; Ager, Francisco J.

    1999-11-16

    The ion beam analysis techniques emerge in the last years as one of the main applications of electrostatic accelerators. A short summary of the most used IBA techniques will be given as well as some examples of applications in interdisciplinary sciences.

  13. Ion Beam Analysis Techniques in Interdisciplinary Applications

    SciTech Connect

    Respaldiza, Miguel A.; Ager, Francisco J.

    1999-12-31

    The ion beam analysis techniques emerge in the last years as one of the main applications of electrostatic accelerators. A short summary of the most used IBA techniques will be given as well as some examples of applications in interdisciplinary sciences.

  14. Safety Analysis of Small Break Loss of Coolant Accident for 1200 MWe Simplified Boiling Water Reactor (SBWR-1200 BDLB)

    SciTech Connect

    Xu, Y.; Revankar, S.T.; Ishii, M.

    2002-07-01

    The objective of this research is to assess the performance of the safety systems during small break loss of coolant accident (SBLOCA) transient in the full size SBWR. RELAP5/MOD3 was used to simulate the blow-down and long-term cooling responses of the various safety systems during the accident transient. An integral test for long-term cooling under low pressure was conducted in a scaled facility with the initial conditions given by the code simulation. The code applicability and the facility scalability were evaluated by the comparison between the test data and the code simulations. The scaling analysis has been done by the comparison of the prototype code predictions and the scaled-up test data with the proper scaling multiplications and time shifting. The good agreement between the major safety parameters has shown the applicability of the RELAP5/MOD3 code and the scalability of the facility for SBWR-1200 safety analysis applications. (authors)

  15. SCAP: a new methodology for safety management based on feedback from credible accident-probabilistic fault tree analysis system.

    PubMed

    Khan, F I; Iqbal, A; Ramesh, N; Abbasi, S A

    2001-10-12

    As it is conventionally done, strategies for incorporating accident--prevention measures in any hazardous chemical process industry are developed on the basis of input from risk assessment. However, the two steps-- risk assessment and hazard reduction (or safety) measures--are not linked interactively in the existing methodologies. This prevents a quantitative assessment of the impacts of safety measures on risk control. We have made an attempt to develop a methodology in which risk assessment steps are interactively linked with implementation of safety measures. The resultant system tells us the extent of reduction of risk by each successive safety measure. It also tells based on sophisticated maximum credible accident analysis (MCAA) and probabilistic fault tree analysis (PFTA) whether a given unit can ever be made 'safe'. The application of the methodology has been illustrated with a case study.

  16. A New Microcell Technique for NMR Analysis.

    ERIC Educational Resources Information Center

    Yu, Sophia J.

    1987-01-01

    Describes a new laboratory technique for working with small samples of compounds used in nuclear magnetic resonance (NMR) analysis. Demonstrates how microcells can be constructed for each experiment and samples can be recycled. (TW)

  17. Statistical Evaluation of Time Series Analysis Techniques

    NASA Technical Reports Server (NTRS)

    Benignus, V. A.

    1973-01-01

    The performance of a modified version of NASA's multivariate spectrum analysis program is discussed. A multiple regression model was used to make the revisions. Performance improvements were documented and compared to the standard fast Fourier transform by Monte Carlo techniques.

  18. Statistical evaluation of vibration analysis techniques

    NASA Technical Reports Server (NTRS)

    Milner, G. Martin; Miller, Patrice S.

    1987-01-01

    An evaluation methodology is presented for a selection of candidate vibration analysis techniques applicable to machinery representative of the environmental control and life support system of advanced spacecraft; illustrative results are given. Attention is given to the statistical analysis of small sample experiments, the quantification of detection performance for diverse techniques through the computation of probability of detection versus probability of false alarm, and the quantification of diagnostic performance.

  19. The epidemiology and cost analysis of patients presented to Emergency Department following traffic accidents

    PubMed Central

    Karadana, Gökçe Akgül; Aksu, Nalan Metin; Akkaş, Meltem; Akman, Canan; Üzümcügil, Akın; Özmen, M. Mahir

    2013-01-01

    Background Traffic accidents are ranked first as the cause of personal injury throughout the world. The high number of traffic accidents yielding injuries and fatalities makes them of great importance to Emergency Departments. Material/Methods Patients admitted to Hacettepe University Faculty of Medicine Adult Emergency Department due to traffic accidents were investigated epidemiologically. Differences between groups were evaluated by Kruskall-Wallis, Mann-Whitney, and Wilcoxon tests. A value of p<0.05 was accepted as statistically significant. Results We included 2003 patients over 16 years of age. The mean age was 39.6±16.1 and 55% were males. Admissions by ambulance and due to motor vehicle accidents were the most common. In 2004 the rate of traffic accidents (15.3%) was higher than the other years, the most common month was May (10.8%), and the most common time period was 6 pm to 12 am (midnight). About half of the patients (51.5%) were admitted in the first 30 minutes. Life-threatening condition was present in 9.6% of the patients. Head trauma was the most common type of trauma, with the rate of 18.3%. Mortality rate was 81.8%. The average length of hospital stay was 403 minutes (6.7 hours) and the average cost per patient was 983±4364 TL. Conclusions Further studies are needed to compare the cost found in this study with the mean cost for Turkey. However, the most important step to reduce the direct and indirect costs due to traffic accidents is the prevention of these accidents. PMID:24316815

  20. Advanced neutron source reactor conceptual safety analysis report, three-element-core design: Chapter 15, accident analysis

    SciTech Connect

    Chen, N.C.J.; Wendel, M.W.; Yoder, G.L.; Harrington, R.M.

    1996-02-01

    In order to utilize reduced enrichment fuel, the three-element-core design for the Advanced Neutron Source has been proposed. The proposed core configuration consists of inner, middle, and outer elements, with the middle element offset axially beneath the inner and outer elements, which are axially aligned. The three-element-core RELAP5 model assumes that the reactor hardware is changed only within the core region, so that the loop piping, heat exchangers, and pumps remain as assumed for the two-element-core configuration. To assess the impact of changes in the core region configuration and the thermal-hydraulic steady-state conditions, the safety analysis has been updated. This report gives the safety margins for the loss-of-off-site power and pressure-boundary fault accidents based on the RELAP5 results. AU margins are greater for the three-element-core simulations than those calculated for the two-element core.

  1. Retrospection of Chernobyl nuclear accident for decision analysis concerning remedial actions in Ukraine

    SciTech Connect

    Georgievskiy, Vladimir

    2007-07-01

    It is considered the efficacy of decisions concerning remedial actions when of-site radiological monitoring in the early and (or) in the intermediate phases was absent or was not informative. There are examples of such situations in the former Soviet Union where many people have been exposed: releases of radioactive materials from 'Krasnoyarsk-26' into Enisey River, releases of radioactive materials from 'Chelabinsk-65' (the Kishtim accident), nuclear tests at the Semipalatinsk Test Site, the Chernobyl nuclear accident etc. If monitoring in the early and (or) in the intermediate phases is absent the decisions concerning remedial actions are usually developed on the base of permanent monitoring. However decisions of this kind may be essentially erroneous. For these cases it is proposed to make retrospection of radiological data of the early and intermediate phases of nuclear accident and to project decisions concerning remedial actions on the base of both retrospective data and permanent monitoring data. In this Report the indicated problem is considered by the example of the Chernobyl accident for Ukraine. Their of-site radiological monitoring in the early and intermediate phases was unsatisfactory. In particular, the pasture-cow-milk monitoring had not been made. All official decisions concerning dose estimations had been made on the base of measurements of {sup 137}Cs in body (40 measurements in 135 days and 55 measurements in 229 days after the Chernobyl accident). For the retrospection of radiological data of the Chernobyl accident dynamic model has been developed. This model has structure similar to the structure of Pathway model and Farmland model. Parameters of the developed model have been identified for agricultural conditions of Russia and Ukraine. By means of this model dynamics of 20 radionuclides in pathways and dynamics of doses have been estimated for the early, intermediate and late phases of the Chernobyl accident. The main results are following

  2. Analysis of 121 fatal passenger car-adult pedestrian accidents in China.

    PubMed

    Zhao, Hui; Yin, Zhiyong; Yang, Guangyu; Che, Xingping; Xie, Jingru; Huang, Wei; Wang, Zhengguo

    2014-10-01

    To study the characteristics of fatal vehicle-pedestrian accidents in China,a team was established and passenger car-pedestrian crash cases occurring between 2006 and 2011 in Beijing and Chongqing, China were collected. A total of 121 fatal passenger car-adult pedestrian collisions were sampled and analyzed. The pedestrian injuries were scored according to Abbreviated Injury Scale (AIS) and Injury Severity Score (ISS). The demographical distributions of fatal pedestrian accidents differed from other pedestrian accidents. Among the victims, no significant discrepancy in the distribution of ISS and AIS in head, thorax, abdomen, and extremities by pedestrian age was found, while pedestrian behaviors prior to the crashes may affect the ISS. The distributions of AIS in head, thorax, and abdomen among the fatalities did not show any association with impact speeds or vehicle types, whereas there was a strong relationship between the ISS and impact speeds. Whether pedestrians died in the accident field or not was not associated with the ISS or AIS. The present results may be useful for not only forensic experts but also vehicle safety researchers. More investigations regarding fatal pedestrian accidents need be conducted in great detail.

  3. APT Blanket System Loss-of-Coolant Accident (LOCA) Analysis Based on Initial Conceptual Design - Case 3: External HR Break at Pump Outlet without Pump Trip

    SciTech Connect

    Hamm, L.L.

    1998-10-07

    This report is one of a series of reports that document normal operation and accident simulations for the Accelerator Production of Tritium (APT) blanket heat removal (HR) system. These simulations were performed for the Preliminary Safety Analysis Report.

  4. Nuclear accidents

    SciTech Connect

    Mobley, J.A.

    1982-05-01

    A nuclear accident with radioactive contamination can happen anywhere in the world. Because expert nuclear emergency teams may take several hours to arrive at the scene, local authorities must have a plan of action for the hours immediately following an accident. The site should be left untouched except to remove casualties. Treatment of victims includes decontamination and meticulous wound debridement. Acute radiation syndrome may be an overwhelming sequela.

  5. What can the drivers' own description from combined sources provide in an analysis of driver distraction and low vigilance in accident situations?

    PubMed

    Tivesten, Emma; Wiberg, Henrik

    2013-03-01

    Accident data play an important role in vehicle safety development. Accident data sources are generally limited in terms of how much information is provided on driver states and behaviour prior to an accident. However, the precise limitations vary between databases, due to differences in analysis focus and data collection procedures between organisations. If information about a specific accident can be retrieved from more than one data source it should be possible to combine the available information sets to facilitate data from one source to compensate for limitations in the other(s). To investigate the viability of such compensation, this study identified a set of accidents recorded in two different data sources. The first data source investigated was an accident mail survey and the second data source insurance claims documents consisting predominantly of insurance claims completed by the involved road users. An analysis of survey variables was compared to a case analysis including word data derived from the same survey and filed insurance claims documents. For each accident, the added value of having access to more than one source of information was assessed. To limit the scope of this study, three particular topics were investigated: available information on low vigilance (e.g., being drowsy, ill); secondary task distraction (e.g., talking with passengers, mobile phone use); and distraction related to the driving task (e.g., looking for approaching vehicles). Results suggest that for low vigilance and secondary task distraction, a combination of the mail survey and insurance claims documents provide more reliable and detailed pre-crash information than survey variables alone. However, driving related distraction appears to be more difficult to capture. In order to gain a better understanding of the above issues and how frequently they occur in accidents, the data sources and analysis methods suggested here may be combined with other investigation methods such

  6. Analysis of hospitalization occurred due to motorcycles accidents in São Paulo city

    PubMed Central

    Gorios, Carlos; Armond, Jane de Eston; Rodrigues, Cintia Leci; Pernambuco, Henrique; Iporre, Ramiro Ortiz; Colombo-Souza, Patrícia

    2015-01-01

    OBJECTIVE: To characterize the motorcycle accidents occurred in the city of São Paulo, SP, Brazil in the year 2013, with emphasis on information about hospital admissions from SIH/SUS. METHODS: This is a retrospective cross-sectional study. The study covered 5,597 motorcyclists traumatized in traffic accident during the year 2013 occurred in the city of São Paulo. A survey was conducted using secondary data from the Information System of Hospitalization Health System (SIH/SUS). RESULTS: In 2013, in the city of São Paulo there were 5,597 admissions of motorcyclists traumatized in traffic accidents, of which 89.8% were male. The admission diagnosis were: leg fracture, femur fracture, and intracranial injury. CONCLUSION: This study confirms other preliminary studies on several points, among which stands out the highest prevalence of male young adults. Level of Evidence II, Retrospective Study. PMID:26327804

  7. A Comprehensive Analysis of the X-15 Flight 3-65 Accident

    NASA Technical Reports Server (NTRS)

    Dennehy, Cornelius J.; Orr, Jeb S.; Barshi, Immanuel; Statler, Irving C.

    2014-01-01

    The November 15, 1967, loss of X-15 Flight 3-65-97 (hereafter referred to as Flight 3-65) was a unique incident in that it was the first and only aerospace flight accident involving loss of crew on a vehicle with an adaptive flight control system (AFCS). In addition, Flight 3-65 remains the only incidence of a single-pilot departure from controlled flight of a manned entry vehicle in a hypersonic flight regime. To mitigate risk to emerging aerospace systems, the NASA Engineering and Safety Center (NESC) proposed a comprehensive review of this accident. The goal of the assessment was to resolve lingering questions regarding the failure modes of the aircraft systems (including the AFCS) and thoroughly analyze the interactions among the human agents and autonomous systems that contributed to the loss of the pilot and aircraft. This document contains the outcome of the accident review.

  8. Development of the simulation system {open_quotes}IMPACT{close_quotes} for analysis of nuclear power plant severe accidents

    SciTech Connect

    Naitoh, Masanori; Ujita, Hiroshi; Nagumo, Hiroichi

    1997-07-01

    The Nuclear Power Engineering Corporation (NUPEC) has initiated a long-term program to develop the simulation system {open_quotes}IMPACT{close_quotes} for analysis of hypothetical severe accidents in nuclear power plants. IMPACT employs advanced methods of physical modeling and numerical computation, and can simulate a wide spectrum of senarios ranging from normal operation to hypothetical, beyond-design-basis-accident events. Designed as a large-scale system of interconnected, hierarchical modules, IMPACT`s distinguishing features include mechanistic models based on first principles and high speed simulation on parallel processing computers. The present plan is a ten-year program starting from 1993, consisting of the initial one-year of preparatory work followed by three technical phases: Phase-1 for development of a prototype system; Phase-2 for completion of the simulation system, incorporating new achievements from basic studies; and Phase-3 for refinement through extensive verification and validation against test results and available real plant data.

  9. Environmental risk management for radiological accidents: integrating risk assessment and decision analysis for remediation at different spatial scales.

    PubMed

    Yatsalo, Boris; Sullivan, Terrence; Didenko, Vladimir; Linkov, Igor

    2011-07-01

    The consequences of the Tohuku earthquake and subsequent tsunami in March 2011 caused a loss of power at the Fukushima Daiichi nuclear power plant, in Japan, and led to the release of radioactive materials into the environment. Although the full extent of the contamination is not currently known, the highly complex nature of the environmental contamination (radionuclides in water, soil, and agricultural produce) typical of nuclear accidents requires a detailed geospatial analysis of information with the ability to extrapolate across different scales with applications to risk assessment models and decision making support. This article briefly summarizes the approach used to inform risk-based land management and remediation decision making after the Chernobyl, Soviet Ukraine, accident in 1986.

  10. Probabilistic accident consequence uncertainty analysis -- Uncertainty assessment for deposited material and external doses. Volume 1: Main report

    SciTech Connect

    Goossens, L.H.J.; Kraan, B.C.P.; Cooke, R.M.; Boardman, J.; Jones, J.A.; Harper, F.T.; Young, M.L.; Hora, S.C.

    1997-12-01

    The development of two new probabilistic accident consequence codes, MACCS and COSYMA, was completed in 1990. These codes estimate the consequence from the accidental releases of radiological material from hypothesized accidents at nuclear installations. In 1991, the US Nuclear Regulatory Commission and the Commission of the European Communities began cosponsoring a joint uncertainty analysis of the two codes. The ultimate objective of this joint effort was to systematically develop credible and traceable uncertainty distributions for the respective code input variables. A formal expert judgment elicitation and evaluation process was identified as the best technology available for developing a library of uncertainty distributions for these consequence parameters. This report focuses on the results of the study to develop distribution for variables related to the MACCS and COSYMA deposited material and external dose models.

  11. Estimating Loss-of-Coolant Accident Frequencies for the Standardized Plant Analysis Risk Models

    SciTech Connect

    S. A. Eide; D. M. Rasmuson; C. L. Atwood

    2008-09-01

    The U.S. Nuclear Regulatory Commission maintains a set of risk models covering the U.S. commercial nuclear power plants. These standardized plant analysis risk (SPAR) models include several loss-of-coolant accident (LOCA) initiating events such as small (SLOCA), medium (MLOCA), and large (LLOCA). All of these events involve a loss of coolant inventory from the reactor coolant system. In order to maintain a level of consistency across these models, initiating event frequencies generally are based on plant-type average performance, where the plant types are boiling water reactors and pressurized water reactors. For certain risk analyses, these plant-type initiating event frequencies may be replaced by plant-specific estimates. Frequencies for SPAR LOCA initiating events previously were based on results presented in NUREG/CR-5750, but the newest models use results documented in NUREG/CR-6928. The estimates in NUREG/CR-6928 are based on historical data from the initiating events database for pressurized water reactor SLOCA or an interpretation of results presented in the draft version of NUREG-1829. The information in NUREG-1829 can be used several ways, resulting in different estimates for the various LOCA frequencies. Various ways NUREG-1829 information can be used to estimate LOCA frequencies were investigated and this paper presents two methods for the SPAR model standard inputs, which differ from the method used in NUREG/CR-6928. In addition, results obtained from NUREG-1829 are compared with actual operating experience as contained in the initiating events database.

  12. The effects of aircraft certification rules on general aviation accidents

    NASA Astrophysics Data System (ADS)

    Anderson, Carolina Lenz

    The purpose of this study was to analyze the frequency of general aviation airplane accidents and accident rates on the basis of aircraft certification to determine whether or not differences in aircraft certification rules had an influence on accidents. In addition, the narrative cause descriptions contained within the accident reports were analyzed to determine whether there were differences in the qualitative data for the different certification categories. The certification categories examined were: Federal Aviation Regulations Part 23, Civil Air Regulations 3, Light Sport Aircraft, and Experimental-Amateur Built. The accident causes examined were those classified as: Loss of Control, Controlled Flight into Terrain, Engine Failure, and Structural Failure. Airworthiness certification categories represent a wide diversity of government oversight. Part 23 rules have evolved from the initial set of simpler design standards and have progressed into a comprehensive and strict set of rules to address the safety issues of the more complex airplanes within the category. Experimental-Amateur Built airplanes have the least amount of government oversight and are the fastest growing segment. The Light Sport Aircraft category is a more recent certification category that utilizes consensus standards in the approval process. Civil Air Regulations 3 airplanes were designed and manufactured under simpler rules but modifying these airplanes has become lengthy and expensive. The study was conducted using a mixed methods methodology which involves both quantitative and qualitative elements. A Chi-Square test was used for a quantitative analysis of the accident frequency among aircraft certification categories. Accident rate analysis of the accidents among aircraft certification categories involved an ANCOVA test. The qualitative component involved the use of text mining techniques for the analysis of the narrative cause descriptions contained within the accident reports. The Chi

  13. Multiattribute Decision Modeling Techniques: A Comparative Analysis

    DTIC Science & Technology

    1988-08-01

    Rating Technique (SMART) as a direct response to Raiffa’s (1969) article on multiattribute utility theory , which Edwards found extremcy stimulating but...approaches such as multiattribute utility /value assessment and hierarchical analysis and have applied these techniques to a number of non-military... multiattributed ) outcomes O(l)...O(k), and if the utility function is denoted by u and the probabilities of the k events are p(l)...p(k), then the

  14. Risk Analysis for Public Consumption: Media Coverage of the Ginna Nuclear Reactor Accident.

    ERIC Educational Resources Information Center

    Dunwoody, Sharon; And Others

    Researchers have determined that the lay public makes risk judgments in ways that are very different from those advocated by scientists. Noting that these differences have caused considerable concern among those who promote and regulate health and safety, a study examined media coverage of the accident at the Robert E. Ginna nuclear power plant…

  15. An Analysis of Incident/Accident Reports from the Texas Secondary School Science Safety Survey, 2001

    ERIC Educational Resources Information Center

    Stephenson, Amanda L.; West, Sandra S.; Westerlund, Julie F.; Nelson, Nancy C.

    2003-01-01

    This study investigated safety in Texas secondary school science laboratory, classroom, and field settings. The Texas Education Agency (TEA) drew a random representative sample consisting of 199 secondary public schools in Texas. Eighty-one teachers completed Incident/Accident Reports. The reports were optional, anonymous, and open-ended; thus,…

  16. Spontaneous abortions after the Three Mile Island nuclear accident: a life table analysis

    SciTech Connect

    Goldhaber, M.K.; Staub, S.L.; Tokuhata, G.K.

    1983-07-01

    A study was conducted to determine whether the incidence of spontaneous abortion was greater than expected near the Three Mile Island (TMI) nuclear power plant during the months following the March 28, 1979 accident. All persons living within five miles of TMI were registered shortly after the accident, and information on pregnancy at the time of the accident was collected. After one year, all pregnancy cases were followed up and outcomes ascertained. Using the life table method, it was found that, given pregnancies after four completed weeks of gestation counting from the first day of the last menstrual period, the estimated incidence of spontaneous abortion (miscarriage before completion of 16 weeks of gestation) was 15.1 per cent for women pregnant at the time of the TMI accident. Combining spontaneous abortions and stillbirths (delivery of a dead fetus after 16 weeks of gestation), the estimated incidence was 16.1 per cent for pregnancies after four completed weeks of gestation. Both incidences are comparable to baseline studies of fetal loss.

  17. [Accident analysis in ex ASL FG/2 Cerignola (FG) related to the period 2001-2001].

    PubMed

    Gadela, Nicola

    2009-01-01

    The purpose of this study was to quantify and qualify the accidents that occurred in the FG/2 local health authority structures (Southern Italy) during the 5-year period 2001-2006, in order to identify their characteristics and to plan the possible preventive strategies that would allow the health workers to operate in a safer environment.

  18. Spontaneous abortions after the Three Mile Island nuclear accident: a life table analysis.

    PubMed Central

    Goldhaber, M K; Staub, S L; Tokuhata, G K

    1983-01-01

    A study was conducted to determine whether the incidence of spontaneous abortion was greater than expected near the Three Mile Island (TMI) nuclear power plant during the months following the March 28, 1979 accident. All persons living within five miles of TMI were registered shortly after the accident, and information on pregnancy at the time of the accident was collected. After one year, all pregnancy cases were followed up and outcomes ascertained. Using the life table method, it was found that, given pregnancies after four completed weeks of gestation counting from the first day of the last menstrual period, the estimated incidence of spontaneous abortion (miscarriage before completion of 16 weeks of gestation) was 15.1 per cent for women pregnant at the time of the TMI accident. Combining spontaneous abortions and stillbirths (delivery of a dead fetus after 16 weeks of gestation), the estimated incidence was 16.1 per cent for pregnancies after four completed weeks of gestation. Both incidences are comparable to baseline studies of fetal loss. PMID:6859357

  19. A Longitudinal Analysis of the Causal Factors in Major Maritime Accidents in the USA and Canada (1996-2006)

    NASA Technical Reports Server (NTRS)

    Johnson, C. W.; Holloway, C, M.

    2007-01-01

    Accident reports provide important insights into the causes and contributory factors leading to particular adverse events. In contrast, this paper provides an analysis that extends across the findings presented over ten years investigations into maritime accidents by both the US National Transportation Safety Board (NTSB) and Canadian Transportation Safety Board (TSB). The purpose of the study was to assess the comparative frequency of a range of causal factors in the reporting of adverse events. In order to communicate our findings, we introduce J-H graphs as a means of representing the proportion of causes and contributory factors associated with human error, equipment failure and other high level classifications in longitudinal studies of accident reports. Our results suggest the proportion of causal and contributory factors attributable to direct human error may be very much smaller than has been suggested elsewhere in the human factors literature. In contrast, more attention should be paid to wider systemic issues, including the managerial and regulatory context of maritime operations.

  20. Analysis and application of relationship between post-braking-distance and throw distance in vehicle-pedestrian accident reconstruction.

    PubMed

    Zou, Tiefang; Yu, Zhi; Cai, Ming; Liu, Jike

    2011-04-15

    Through theoretical analysis and introduction of some empirical parameters, the relationship between post-braking-distance and throw distance was studied concentratedly. Here, the post-braking-distance is the distance a vehicle will travel from the impact position to when it comes to a complete stop. Two useful formulas which are meaningful in vehicle-pedestrian accident reconstruction were finally obtained. The first one can be used to calculate impact speed according to throw distance, while the other one can describe the relationship between post-braking-distance and throw distance. Their feasibility has been validated by comparing with other scholars' empirical formulas and simulation results of software Pc-Crash, respectively. The relationship between post-braking-distance and throw distance has very bright application perspective in vehicle-pedestrian accident reconstruction such as helping policemen obtain more useful evidences, validating credibility of the throw distance, judging whether the vehicle is fully braked or not, determining the impact position etc. Finally its application was demonstrated by three cases, in which the impact speed was also calculated. All results until now have shown that conclusions obtained in this article are feasible and helpful in vehicle-pedestrian accident reconstruction.

  1. Validation and verification of RELAP5 for Advanced Neutron Source accident analysis: Part I, comparisons to ANSDM and PRSDYN codes

    SciTech Connect

    Chen, N.C.J.; Ibn-Khayat, M.; March-Leuba, J.A.; Wendel, M.W.

    1993-12-01

    As part of verification and validation, the Advanced Neutron Source reactor RELAP5 system model was benchmarked by the Advanced Neutron Source dynamic model (ANSDM) and PRSDYN models. RELAP5 is a one-dimensional, two-phase transient code, developed by the Idaho National Engineering Laboratory for reactor safety analysis. Both the ANSDM and PRSDYN models use a simplified single-phase equation set to predict transient thermal-hydraulic performance. Brief descriptions of each of the codes, models, and model limitations were included. Even though comparisons were limited to single-phase conditions, a broad spectrum of accidents was benchmarked: a small loss-of-coolant-accident (LOCA), a large LOCA, a station blackout, and a reactivity insertion accident. The overall conclusion is that the three models yield similar results if the input parameters are the same. However, ANSDM does not capture pressure wave propagation through the coolant system. This difference is significant in very rapid pipe break events. Recommendations are provided for further model improvements.

  2. Fukushima Daiichi Unit 1 Accident Progression Uncertainty Analysis and Implications for Decommissioning of Fukushima Reactors - Volume I.

    SciTech Connect

    Gauntt, Randall O.; Mattie, Patrick D.

    2016-01-01

    Sandia National Laboratories (SNL) has conducted an uncertainty analysis (UA) on the Fukushima Daiichi unit (1F1) accident progression with the MELCOR code. The model used was developed for a previous accident reconstruction investigation jointly sponsored by the US Department of Energy (DOE) and Nuclear Regulatory Commission (NRC). That study focused on reconstructing the accident progressions, as postulated by the limited plant data. This work was focused evaluation of uncertainty in core damage progression behavior and its effect on key figures-of-merit (e.g., hydrogen production, reactor damage state, fraction of intact fuel, vessel lower head failure). The primary intent of this study was to characterize the range of predicted damage states in the 1F1 reactor considering state of knowledge uncertainties associated with MELCOR modeling of core damage progression and to generate information that may be useful in informing the decommissioning activities that will be employed to defuel the damaged reactors at the Fukushima Daiichi Nuclear Power Plant. Additionally, core damage progression variability inherent in MELCOR modeling numerics is investigated.

  3. Launch Vehicle Fire Accident Preliminary Analysis of a Liquid-Metal Cooled Thermionic Nuclear Reactor: TOPAZ-II

    NASA Astrophysics Data System (ADS)

    Hu, G.; Zhao, S.; Ruan, K.

    2012-01-01

    In this paper, launch vehicle propellant fire accident analysis of TOPAZ-II reactor has been done by a thermionic reactor core analytic code-TATRHG(A) developed by author. When a rocket explodes on a launch pad, its payload-TOPAZ-II can be subjected to a severe thermal environment from the resulting fireball. The extreme temperatures associated with propellant fires can create a destructive environment in or near the fireball. Different kind of propellants - liquid propellant and solid propellant which will lead to different fire temperature are considered. Preliminary analysis shows that the solid propellant fires can melt the whole toxic beryllium radial reflector.

  4. DIANA: A multi-phase, multi-component hydrodynamic model for the analysis of severe accidents in heavy water reactors with multiple-tube assemblies

    SciTech Connect

    Tentner, A.M.

    1994-03-01

    A detailed hydrodynamic fuel relocation model has been developed for the analysis of severe accidents in Heavy Water Reactors with multiple-tube Assemblies. This model describes the Fuel Disruption and Relocation inside a nuclear fuel assembly and is designated by the acronym DIANA. DIANA solves the transient hydrodynamic equations for all the moving materials in the core and treats all the relevant flow regimes. The numerical solution techniques and some of the physical models included in DIANA have been developed taking advantage of the extensive experience accumulated in the development and validation of the LEVITATE (1) fuel relocation model of SAS4A [2, 3]. The model is designed to handle the fuel and cladding relocation in both voided and partially voided channels. It is able to treat a wide range of thermal/ hydraulic/neutronic conditions and the presence of various flow regimes at different axial locations within the same hydrodynamic channel.

  5. A review of sensitivity analysis techniques

    SciTech Connect

    Hamby, D.M.

    1993-12-31

    Mathematical models are utilized to approximate various highly complex engineering, physical, environmental, social, and economic phenomena. Model parameters exerting the most influence on model results are identified through a {open_quotes}sensitivity analysis.{close_quotes} A comprehensive review is presented of more than a dozen sensitivity analysis methods. The most fundamental of sensitivity techniques utilizes partial differentiation whereas the simplest approach requires varying parameter values one-at-a-time. Correlation analysis is used to determine relationships between independent and dependent variables. Regression analysis provides the most comprehensive sensitivity measure and is commonly utilized to build response surfaces that approximate complex models.

  6. Techniques for the Analysis of Human Movement.

    ERIC Educational Resources Information Center

    Grieve, D. W.; And Others

    This book presents the major analytical techniques that may be used in the appraisal of human movement. Chapter 1 is devoted to the photopgraphic analysis of movement with particular emphasis on cine filming. Cine film may be taken with little or no restriction on the performer's range of movement; information on the film is permanent and…

  7. Analysis of the effect of car size on accident injury probability using automobile insurance data.

    PubMed

    Krishnan, K S; Carnahan, J V

    1985-04-01

    The Highway Loss Data Institute (HLDI) compiles injury and collision claim information from major insurance companies. These data have indicated that a disproportionately large number of injury claims are made for small cars. As a result, it might be concluded that small cars increase injury risk to their occupants. Recent advertisements by a major automobile manufacturer suggest a similar conclusion should be drawn from these data. In this paper it is shown that the apparent higher injury risk attributed to small cars can reflect the behavior of persons driving small cars. The number of injury claim accidents per collision claim accident is examined as an alternative measure of injury risk. Possible problems in interpretation are discussed.

  8. Analysis of potential for jet-impingement erosion from leaking steam generator tubes during severe accidents.

    SciTech Connect

    Majumdar, S.; Diercks, D. R.; Shack, W. J.; Energy Technology

    2002-05-01

    This report summarizes analytical evaluation of crack-opening areas and leak rates of superheated steam through flaws in steam generator tubes and erosion of neighboring tubes due to jet impingement of superheated steam with entrained particles from core debris created during severe accidents. An analytical model for calculating crack-opening area as a function of time and temperature was validated with tests on tubes with machined flaws. A three-dimensional computational fluid dynamics code was used to calculate the jet velocity impinging on neighboring tubes as a function of tube spacing and crack-opening area. Erosion tests were conducted in a high-temperature, high-velocity erosion rig at the University of Cincinnati, using micrometer-sized nickel particles mixed in with high-temperature gas from a burner. The erosion results, together with analytical models, were used to estimate the erosive effects of superheated steam with entrained aerosols from the core during severe accidents.

  9. Accident simulation and consequence analysis in support of MHTGR safety evaluations

    SciTech Connect

    Ball, S.J.; Wichner, R.P.; Smith, O.L.; Conklin, J.C. ); Barthold, W.P. )

    1991-01-01

    This paper summarizes research performed at Oak Ridge National Laboratory (ORNL) to assist the Nuclear Regulatory Commission (NRC) in preliminary determinations of licensability of the US Department of Energy (DOE) reference design of a standard modular high-temperature gas-cooled reactor (MHTGR). The work described includes independent analyses of core heatup and steam ingress accidents, and the reviews and analyses of fuel performance and fission product transport technology.

  10. Third annual Warren K. Sinclair keynote address: retrospective analysis of impacts of the Chernobyl accident.

    PubMed

    Balonov, Mikhail

    2007-11-01

    The accident at the Chernobyl Nuclear Power Plant in 1986 was the most severe in the history of the nuclear industry, causing a huge release of radionuclides over large areas of Europe. The recently completed Chernobyl Forum concluded that after a number of years, along with reduction of radiation levels and accumulation of humanitarian consequences, severe social and economic depression of the affected regions and associated psychological problems of the general public and the workers had become the most significant problem to be addressed by the authorities. The majority of the >600,000 emergency and recovery operation workers and five million residents of the contaminated areas in Belarus, Russia, and Ukraine received relatively minor radiation doses which are comparable with the natural background levels. An exception is a cohort of several hundred emergency workers who received high radiation doses and of whom 28 persons died in 1986 due to acute radiation sickness. Apart from the dramatic increase in thyroid cancer incidence among those exposed to radioiodine at a young age and some increase of leukemia in the most exposed workers, there is no clearly demonstrated increase in the somatic diseases due to radiation. There was, however, an increase in psychological problems among the affected population, compounded by the social disruption that followed the break-up of the Soviet Union. Despite the unprecedented scale of the Chernobyl accident, its consequences on the health of people are far less severe than those of the atomic bombings of the cities of Hiroshima and Nagasaki. Studying the consequences of the Chernobyl accident has made an invaluable scientific contribution to the development of nuclear safety, radioecology, radiation medicine and protection, and also the social sciences. The Chernobyl accident initiated the global nuclear and radiation safety regime.

  11. Review of Cytogenetic analysis of restoration workers for Fukushima Daiichi nuclear power station accident.

    PubMed

    Suto, Yumiko

    2016-09-01

    Japan faced with the nuclear accident of the Fukushima Daiichi Nuclear Power Station (NPS) caused by the combined disaster of the Great East Japan Earthquake and the subsequent tsunamis on 11 March 2011. National Institute of Radiological Sciences received all nuclear workers who were engaged in emergency response tasks at the NPS and suspected of being overexposed to acute radiation. Biological dosimetry by dicentric chromosome assay was helpful for medical triage and management of the workers.

  12. An Analysis of Human Causal Factors in Unmanned Aerial Vehicle (UAV) Accidents

    DTIC Science & Technology

    2014-12-01

    PC 306 • Fatigue ( sleep deprivation ) PC 307 • Circadian rhythm de-synchronization (e.g., jet lag or shift work) PC 308 • Motion sickness PC...AERIAL VEHICLE (UAV) ACCIDENTS 5. FUNDING NUMBERS 6. AUTHOR(S) Mehmet Oncu and Suleyman Yildiz 7. PERFORMING ORGANIZATION NAME(S) AND ADDRESS(ES...Naval Postgraduate School Monterey, CA 93943-5000 8. PERFORMING ORGANIZATION REPORT NUMBER 9. SPONSORING /MONITORING AGENCY NAME(S) AND

  13. 3D analysis of the reactivity insertion accident in VVER-1000

    SciTech Connect

    Abdullayev, A. M.; Zhukov, A. I.; Slyeptsov, S. M.

    2012-07-01

    Fuel parameters such as peak enthalpy and temperature during rod ejection accident are calculated. The calculations are performed by 3D neutron kinetics code NESTLE and 3D thermal-hydraulic code VIPRE-W. Both hot zero power and hot full power cases were studied for an equilibrium cycle with Westinghouse hex fuel in VVER-1000. It is shown that the use of 3D methodology can significantly increase safety margins for current criteria and met future criteria. (authors)

  14. Microextraction sample preparation techniques in biomedical analysis.

    PubMed

    Szultka, Malgorzata; Pomastowski, Pawel; Railean-Plugaru, Viorica; Buszewski, Boguslaw

    2014-11-01

    Biologically active compounds are found in biological samples at relatively low concentration levels. The sample preparation of target compounds from biological, pharmaceutical, environmental, and food matrices is one of the most time-consuming steps in the analytical procedure. The microextraction techniques are dominant. Metabolomic studies also require application of proper analytical technique for the determination of endogenic metabolites present in biological matrix on trace concentration levels. Due to the reproducibility of data, precision, relatively low cost of the appropriate analysis, simplicity of the determination, and the possibility of direct combination of those techniques with other methods (combination types on-line and off-line), they have become the most widespread in routine determinations. Additionally, sample pretreatment procedures have to be more selective, cheap, quick, and environmentally friendly. This review summarizes the current achievements and applications of microextraction techniques. The main aim is to deal with the utilization of different types of sorbents for microextraction and emphasize the use of new synthesized sorbents as well as to bring together studies concerning the systematic approach to method development. This review is dedicated to the description of microextraction techniques and their application in biomedical analysis.

  15. SiC MODIFICATIONS TO MELCOR FOR SEVERE ACCIDENT ANALYSIS APPLICATIONS

    SciTech Connect

    Brad J. Merrill; Shannon M Bragg-Sitton

    2013-09-01

    The Department of Energy (DOE) Office of Nuclear Energy (NE) Light Water Reactor (LWR) Sustainability Program encompasses strategic research focused on improving reactor core economics and safety margins through the development of an advanced fuel cladding system. The Fuels Pathway within this program focuses on fuel system components outside of the fuel pellet, allowing for alteration of the existing zirconium-based clad system through coatings, addition of ceramic sleeves, or complete replacement (e.g. fully ceramic cladding). The DOE-NE Fuel Cycle Research & Development (FCRD) Advanced Fuels Campaign (AFC) is also conducting research on materials for advanced, accident tolerant fuels and cladding for application in operating LWRs. To aide in this assessment, a silicon carbide (SiC) version of the MELCOR code was developed by substituting SiC in place of Zircaloy in MELCOR’s reactor core oxidation and material property routines. The purpose of this development effort is to provide a numerical capability for estimating the safety advantages of replacing Zr-alloy components in LWRs with SiC components. This modified version of the MELCOR code was applied to the Three Mile Island (TMI-2) plant accident. While the results are considered preliminary, SiC cladding showed a dramatic safety advantage over Zircaloy cladding during this accident.

  16. Analysis of Radionuclide Releases from the Fukushima Dai-ichi Nuclear Power Plant Accident Part II

    NASA Astrophysics Data System (ADS)

    Achim, Pascal; Monfort, Marguerite; Le Petit, Gilbert; Gross, Philippe; Douysset, Guilhem; Taffary, Thomas; Blanchard, Xavier; Moulin, Christophe

    2014-03-01

    The present part of the publication (Part II) deals with long range dispersion of radionuclides emitted into the atmosphere during the Fukushima Dai-ichi accident that occurred after the March 11, 2011 tsunami. The first part (Part I) is dedicated to the accident features relying on radionuclide detections performed by monitoring stations of the Comprehensive Nuclear Test Ban Treaty Organization network. In this study, the emissions of the three fission products Cs-137, I-131 and Xe-133 are investigated. Regarding Xe-133, the total release is estimated to be of the order of 6 × 1018 Bq emitted during the explosions of units 1, 2 and 3. The total source term estimated gives a fraction of core inventory of about 8 × 1018 Bq at the time of reactors shutdown. This result suggests that at least 80 % of the core inventory has been released into the atmosphere and indicates a broad meltdown of reactor cores. Total atmospheric releases of Cs-137 and I-131 aerosols are estimated to be 1016 and 1017 Bq, respectively. By neglecting gas/particulate conversion phenomena, the total release of I-131 (gas + aerosol) could be estimated to be 4 × 1017 Bq. Atmospheric transport simulations suggest that the main air emissions have occurred during the events of March 14, 2011 (UTC) and that no major release occurred after March 23. The radioactivity emitted into the atmosphere could represent 10 % of the Chernobyl accident releases for I-131 and Cs-137.

  17. Probabilistic accident consequence uncertainty analysis: Food chain uncertainty assessment. Volume 1: Main report

    SciTech Connect

    Brown, J.; Goossens, L.H.J.; Kraan, B.C.P.

    1997-06-01

    This volume is the first of a two-volume document that summarizes a joint project conducted by the US Nuclear Regulatory Commission and the European Commission to assess uncertainties in the MACCS and COSYMA probabilistic accident consequence codes. These codes were developed primarily for estimating the risks presented by nuclear reactors based on postulated frequencies and magnitudes of potential accidents. This document reports on an ongoing project to assess uncertainty in the MACCS and COSYMA calculations for the offsite consequences of radionuclide releases by hypothetical nuclear power plant accidents. A panel of sixteen experts was formed to compile credible and traceable uncertainty distributions for food chain variables that affect calculations of offsite consequences. The expert judgment elicitation procedure and its outcomes are described in these volumes. Other panels were formed to consider uncertainty in other aspects of the codes. Their results are described in companion reports. Volume 1 contains background information and a complete description of the joint consequence uncertainty study. Volume 2 contains appendices that include (1) a summary of the MACCS and COSYMA consequence codes, (2) the elicitation questionnaires and case structures for both panels, (3) the rationales and results for the panels on soil and plant transfer and animal transfer, (4) short biographies of the experts, and (5) the aggregated results of their responses.

  18. An analysis of thermionic space nuclear reactor power system: I. Effect of disassembling radial reflector, following a reactivity initiated accident

    SciTech Connect

    El-Genk, M.S.; Paramonov, D. )

    1993-01-10

    An analysis is performed to determine the effect of disassembling the radial reflector of the TOPAZ-II reactor, following a hypothetical severe Reactivity Initiated Accident (RIA). Such an RIA is assumed to occur during the system start-up in orbit due to a malfunction of the drive mechanism of the control drums, causing the drums to rotate the full 180[degree] outward at their maximum speed of 1.4[degree]/s. Results indicate that disassembling only three of twelve radial reflector panels would successfully shutdown the reactor, with little overheating of the fuel and the moderator.

  19. Photogrammetric Techniques for Road Surface Analysis

    NASA Astrophysics Data System (ADS)

    Knyaz, V. A.; Chibunichev, A. G.

    2016-06-01

    The quality and condition of a road surface is of great importance for convenience and safety of driving. So the investigations of the behaviour of road materials in laboratory conditions and monitoring of existing roads are widely fulfilled for controlling a geometric parameters and detecting defects in the road surface. Photogrammetry as accurate non-contact measuring method provides powerful means for solving different tasks in road surface reconstruction and analysis. The range of dimensions concerned in road surface analysis can have great variation from tenths of millimetre to hundreds meters and more. So a set of techniques is needed to meet all requirements of road parameters estimation. Two photogrammetric techniques for road surface analysis are presented: for accurate measuring of road pavement and for road surface reconstruction based on imagery obtained from unmanned aerial vehicle. The first technique uses photogrammetric system based on structured light for fast and accurate surface 3D reconstruction and it allows analysing the characteristics of road texture and monitoring the pavement behaviour. The second technique provides dense 3D model road suitable for road macro parameters estimation.

  20. Alternative method of highway traffic safety analysis for developing countries using delphi technique and Bayesian network.

    PubMed

    Mbakwe, Anthony C; Saka, Anthony A; Choi, Keechoo; Lee, Young-Jae

    2016-08-01

    Highway traffic accidents all over the world result in more than 1.3 million fatalities annually. An alarming number of these fatalities occurs in developing countries. There are many risk factors that are associated with frequent accidents, heavy loss of lives, and property damage in developing countries. Unfortunately, poor record keeping practices are very difficult obstacle to overcome in striving to obtain a near accurate casualty and safety data. In light of the fact that there are numerous accident causes, any attempts to curb the escalating death and injury rates in developing countries must include the identification of the primary accident causes. This paper, therefore, seeks to show that the Delphi Technique is a suitable alternative method that can be exploited in generating highway traffic accident data through which the major accident causes can be identified. In order to authenticate the technique used, Korea, a country that underwent similar problems when it was in its early stages of development in addition to the availability of excellent highway safety records in its database, is chosen and utilized for this purpose. Validation of the methodology confirms the technique is suitable for application in developing countries. Furthermore, the Delphi Technique, in combination with the Bayesian Network Model, is utilized in modeling highway traffic accidents and forecasting accident rates in the countries of research.

  1. Solution Techniques in Finite Element Analysis.

    DTIC Science & Technology

    1983-05-01

    CR 83.027 NAVAL CIVIL ENGINEERING LABORATORY Port Hueneme, California Sponsored by NAVAL FACILITIES ENGINEERING COMMAND ___ SOLUTION TECHNIQUES IN...CATALOG NUMBER CR 83.027 A bA/Z3 SZ *4 TITLE fori SoobIt, S TYPE F REP RT II PERIOD COVERED SOLUTION TECHNIQUES IN FINITE ELEMENT Not 192in Jna98 ANALYSIS...elements; nonlinear algebraic equations; numierical solution methods 20 ABSTRACT (Contlinue mI e.se mde It nc..Ac.. Wd ordonhifI, by block .- abe,) ,A

  2. Of Disasters and Dragon Kings: A Statistical Analysis of Nuclear Power Incidents and Accidents.

    PubMed

    Wheatley, Spencer; Sovacool, Benjamin; Sornette, Didier

    2017-01-01

    We perform a statistical study of risk in nuclear energy systems. This study provides and analyzes a data set that is twice the size of the previous best data set on nuclear incidents and accidents, comparing three measures of severity: the industry standard International Nuclear Event Scale, the Nuclear Accident Magnitude Scale of radiation release, and cost in U.S. dollars. The rate of nuclear accidents with cost above 20 MM 2013 USD, per reactor per year, has decreased from the 1970s until the present time. Along the way, the rate dropped significantly after Chernobyl (April 1986) and is expected to be roughly stable around a level of 0.003, suggesting an average of just over one event per year across the current global fleet. The distribution of costs appears to have changed following the Three Mile Island major accident (March 1979). The median cost became approximately 3.5 times smaller, but an extremely heavy tail emerged, being well described by a Pareto distribution with parameter α = 0.5-0.6. For instance, the cost of the two largest events, Chernobyl and Fukushima (March 2011), is equal to nearly five times the sum of the 173 other events. We also document a significant runaway disaster regime in both radiation release and cost data, which we associate with the "dragon-king" phenomenon. Since the major accident at Fukushima (March 2011) occurred recently, we are unable to quantify an impact of the industry response to this disaster. Excluding such improvements, in terms of costs, our range of models suggests that there is presently a 50% chance that (i) a Fukushima event (or larger) occurs every 60-150 years, and (ii) that a Three Mile Island event (or larger) occurs every 10-20 years. Further-even assuming that it is no longer possible to suffer an event more costly than Chernobyl or Fukushima-the expected annual cost and its standard error bracket the cost of a new plant. This highlights the importance of improvements not only immediately following

  3. An epidemiological analysis of drunk driving accidents in Kagawa Prefecture - comparison of 1997-2000 and 2003-2006.

    PubMed

    Fujita, Yoshitsugu; Inoue, Ken; Sakuta, Akira; Seki, Nobuhiko; Miyazawa, Teruomi; Eguchi, Kenji

    2008-10-01

    In this study, we examined the number of drunk driving accidents and drunk driving accident toll in 1997-2000 and 2003-2006 for Kagawa Prefecture, which had Japan's highest number of traffic accident fatalities per 100,000 population.

  4. Signal Analysis Techniques for Interpreting Electroencephalograms

    DTIC Science & Technology

    1980-12-01

    et al. Near-orthogonal basis functions: A real time fetal ECG technique. IEEE Trans Biomed Eng BME-24:39-43 (1971. 66. MacKay, D. M., and D. A...multivariate and nonlinear time series analysis of fetal heart rate. Ph.D. Dissertation, Carnegie-wellon Univ., Pittsburgh, Pa., 1979. Jarisch, W...of fetal heart rate variability. IEEE Trans Biomed Eng (Submitted, 1979). Johnson, A. S. Automated detection of petit mal seizures in the human EEG

  5. Finite element analysis of head-neck kinematics during motor vehicle accidents: analysis in multiple planes.

    PubMed

    Teo, Ee Chon; Zhang, Qing Hang; Huang, Russel C

    2007-01-01

    In this study, a detailed three-dimensional head-neck (C0-C7) finite element (FE) model developed previously based on the actual geometry of a human cadaver specimen was used. Five simulation analyses were performed to investigate the kinematic responses of the head-neck complex under rear-end, front, side, rear- and front-side impacts. Under rear-end and front impacts, it was predicted that the global and intervertebral rotations of the head-neck in the sagittal plane displayed nearly symmetric curvatures about the frontal plane. The primary sagittal rotational angles of the neck under direct front and rear-end impact conditions were higher than the primary frontal rotational angles under other side impact conditions. The analysis predicted early S-shaped and subsequent C-shaped curvatures of the head-neck complex in the sagittal plane under front and rear-end impact, and in the frontal plane under side impact. The head-neck complex flexed laterally in one direction with peak magnitude of larger than 22 degrees and a duration of about 130 ms before flexing in the opposite direction under both side and rear-side impact, compared to the corresponding values of about 15 degrees and 105 ms under front-side impact. The C0-C7 FE model has reasonably predicted the effects of impact direction in the primary sagittal and frontal segmental motion and curvatures of the head-neck complex under various impact conditions.

  6. Infusing Reliability Techniques into Software Safety Analysis

    NASA Technical Reports Server (NTRS)

    Shi, Ying

    2015-01-01

    Software safety analysis for a large software intensive system is always a challenge. Software safety practitioners need to ensure that software related hazards are completely identified, controlled, and tracked. This paper discusses in detail how to incorporate the traditional reliability techniques into the entire software safety analysis process. In addition, this paper addresses how information can be effectively shared between the various practitioners involved in the software safety analyses. The author has successfully applied the approach to several aerospace applications. Examples are provided to illustrate the key steps of the proposed approach.

  7. Accelerometer Data Analysis and Presentation Techniques

    NASA Technical Reports Server (NTRS)

    Rogers, Melissa J. B.; Hrovat, Kenneth; McPherson, Kevin; Moskowitz, Milton E.; Reckart, Timothy

    1997-01-01

    The NASA Lewis Research Center's Principal Investigator Microgravity Services project analyzes Orbital Acceleration Research Experiment and Space Acceleration Measurement System data for principal investigators of microgravity experiments. Principal investigators need a thorough understanding of data analysis techniques so that they can request appropriate analyses to best interpret accelerometer data. Accelerometer data sampling and filtering is introduced along with the related topics of resolution and aliasing. Specific information about the Orbital Acceleration Research Experiment and Space Acceleration Measurement System data sampling and filtering is given. Time domain data analysis techniques are discussed and example environment interpretations are made using plots of acceleration versus time, interval average acceleration versus time, interval root-mean-square acceleration versus time, trimmean acceleration versus time, quasi-steady three dimensional histograms, and prediction of quasi-steady levels at different locations. An introduction to Fourier transform theory and windowing is provided along with specific analysis techniques and data interpretations. The frequency domain analyses discussed are power spectral density versus frequency, cumulative root-mean-square acceleration versus frequency, root-mean-square acceleration versus frequency, one-third octave band root-mean-square acceleration versus frequency, and power spectral density versus frequency versus time (spectrogram). Instructions for accessing NASA Lewis Research Center accelerometer data and related information using the internet are provided.

  8. Analysis techniques for residual acceleration data

    NASA Technical Reports Server (NTRS)

    Rogers, Melissa J. B.; Alexander, J. Iwan D.; Snyder, Robert S.

    1990-01-01

    Various aspects of residual acceleration data are of interest to low-gravity experimenters. Maximum and mean values and various other statistics can be obtained from data as collected in the time domain. Additional information may be obtained through manipulation of the data. Fourier analysis is discussed as a means of obtaining information about dominant frequency components of a given data window. Transformation of data into different coordinate axes is useful in the analysis of experiments with different orientations and can be achieved by the use of a transformation matrix. Application of such analysis techniques to residual acceleration data provides additional information than what is provided in a time history and increases the effectiveness of post-flight analysis of low-gravity experiments.

  9. Analysis of Japanese Radionuclide Monitoring Data of Food Before and After the Fukushima Nuclear Accident

    PubMed Central

    2015-01-01

    In an unprecedented food monitoring campaign for radionuclides, the Japanese government took action to secure food safety after the Fukushima nuclear accident (Mar. 11, 2011). In this work we analyze a part of the immense data set, in particular radiocesium contaminations in food from the first year after the accident. Activity concentrations in vegetables peaked immediately after the campaign had commenced, but they decreased quickly, so that by early summer 2011 only a few samples exceeded the regulatory limits. Later, accumulating mushrooms and dried produce led to several exceedances of the limits again. Monitoring of meat started with significant delay, especially outside Fukushima prefecture. After a buildup period, contamination levels of meat peaked by July 2011 (beef). Levels then decreased quickly, but peaked again in September 2011, which was primarily due to boar meat (a known accumulator of radiocesium). Tap water was less contaminated; any restrictions for tap water were canceled by April 1, 2011. Pre-Fukushima 137Cs and 90Sr levels (resulting from atmospheric nuclear explosions) in food were typically lower than 0.5 Bq/kg, whereby meat was typically higher in 137Cs and vegetarian produce was usually higher in 90Sr. The correlation of background radiostrontium and radiocesium indicated that the regulatory assumption after the Fukushima accident of a maximum activity of 90Sr being 10% of the respective 137Cs concentrations may soon be at risk, as the 90Sr/137Cs ratio increases with time. This should be taken into account for the current Japanese food policy as the current regulation will soon underestimate the 90Sr content of Japanese foods. PMID:25621976

  10. Analysis of Japanese radionuclide monitoring data of food before and after the Fukushima nuclear accident.

    PubMed

    Merz, Stefan; Shozugawa, Katsumi; Steinhauser, Georg

    2015-03-03

    In an unprecedented food monitoring campaign for radionuclides, the Japanese government took action to secure food safety after the Fukushima nuclear accident (Mar. 11, 2011). In this work we analyze a part of the immense data set, in particular radiocesium contaminations in food from the first year after the accident. Activity concentrations in vegetables peaked immediately after the campaign had commenced, but they decreased quickly, so that by early summer 2011 only a few samples exceeded the regulatory limits. Later, accumulating mushrooms and dried produce led to several exceedances of the limits again. Monitoring of meat started with significant delay, especially outside Fukushima prefecture. After a buildup period, contamination levels of meat peaked by July 2011 (beef). Levels then decreased quickly, but peaked again in September 2011, which was primarily due to boar meat (a known accumulator of radiocesium). Tap water was less contaminated; any restrictions for tap water were canceled by April 1, 2011. Pre-Fukushima (137)Cs and (90)Sr levels (resulting from atmospheric nuclear explosions) in food were typically lower than 0.5 Bq/kg, whereby meat was typically higher in (137)Cs and vegetarian produce was usually higher in (90)Sr. The correlation of background radiostrontium and radiocesium indicated that the regulatory assumption after the Fukushima accident of a maximum activity of (90)Sr being 10% of the respective (137)Cs concentrations may soon be at risk, as the (90)Sr/(137)Cs ratio increases with time. This should be taken into account for the current Japanese food policy as the current regulation will soon underestimate the (90)Sr content of Japanese foods.

  11. SACO-1: a fast-running LMFBR accident-analysis code

    SciTech Connect

    Mueller, C.J.; Cahalan, J.E.; Vaurio, J.K.

    1980-01-01

    SACO is a fast-running computer code that simulates hypothetical accidents in liquid-metal fast breeder reactors to the point of permanent subcriticality or to the initiation of a prompt-critical excursion. In the tradition of the SAS codes, each subassembly is modeled by a representative fuel pin with three distinct axial regions to simulate the blanket and core regions. However, analytic and integral models are used wherever possible to cut down the computing time and storage requirements. The physical models and basic equations are described in detail. Comparisons of SACO results to analogous SAS3D results comprise the qualifications of SACO and are illustrated and discussed.

  12. Analysis of a small break loss-of-coolant accident of pressurized water reactor by APROS

    SciTech Connect

    Al-Falahi, A.; Haennine, M.; Porkholm, K.

    1995-09-01

    The purpose of this paper is to study the capability of APROS (Advanced PROcess Simulator) code to simulate the real plant thermal-hydraulic transient of a Small Break Loss-Of-Coolant Accident (SBLOCA) of Loss-Of-Fluid Test (LOFT) facility. The LOFT is a scaled model of a Pressurized Water Reactor (PWR). This work is a part of a larger validation of the APROS thermal-hydraulic models. The results of SBLOCA transient calculated by APROS showed a reasonable agreement with the measured data.

  13. Resolve! Version 2.5: Flammable Gas Accident Analysis Tool Acceptance Test Plan and Test Results

    SciTech Connect

    LAVENDER, J.C.

    2000-10-17

    RESOLVE! Version 2 .5 is designed to quantify the risk and uncertainty of combustion accidents in double-shell tanks (DSTs) and single-shell tanks (SSTs). The purpose of the acceptance testing is to ensure that all of the options and features of the computer code run; to verify that the calculated results are consistent with each other; and to evaluate the effects of the changes to the parameter values on the frequency and consequence trends associated with flammable gas deflagrations or detonations.

  14. [Analysis of the implantation of the healthcare network for victims of accidents and violence following the guidelines of the National Policy for the Reduction of Morbidity and Mortality from Violence and Accidents].

    PubMed

    Minayo, Maria Cecília de Souza; Deslandes, Suely Ferreira

    2009-01-01

    In this article we problematize the results of an investigation entitled 'Diagnostic Analysis of the National Policy for Reduction of Morbidity and Mortality from Accidents and Violence (PNRMVA)' and present some thoughts for discussion. Based on a quantitative and qualitative analysis of the implantation of this policy in five Brazilian state capitals--Recife, Rio de Janeiro, Manaus, Curitiba and Brasília and vicinities--along with the participation of local academic institutions we performed a diagnosis of the situation. The article presents evaluative information regarding: the profile of morbidity and mortality from accidents and violence; the adequacy of mobile and fixed pre-hospital emergency services, hospital services and rehabilitation services to preventing the described epidemiological profile; the training of the professionals dealing with these traumas; surveillance and monitoring of violence and accidents as well as support for studies and investigations into the issue. Aimed at proposing a debate, the article concludes raising questions about the advances made in the implementation of the policy, about the fragilities of the system and about the possibilities for an efficient implementation of the PNRMVA guidelines.

  15. Electrical Load Profile Analysis Using Clustering Techniques

    NASA Astrophysics Data System (ADS)

    Damayanti, R.; Abdullah, A. G.; Purnama, W.; Nandiyanto, A. B. D.

    2017-03-01

    Data mining is one of the data processing techniques to collect information from a set of stored data. Every day the consumption of electricity load is recorded by Electrical Company, usually at intervals of 15 or 30 minutes. This paper uses a clustering technique, which is one of data mining techniques to analyse the electrical load profiles during 2014. The three methods of clustering techniques were compared, namely K-Means (KM), Fuzzy C-Means (FCM), and K-Means Harmonics (KHM). The result shows that KHM is the most appropriate method to classify the electrical load profile. The optimum number of clusters is determined using the Davies-Bouldin Index. By grouping the load profile, the demand of variation analysis and estimation of energy loss from the group of load profile with similar pattern can be done. From the group of electric load profile, it can be known cluster load factor and a range of cluster loss factor that can help to find the range of values of coefficients for the estimated loss of energy without performing load flow studies.

  16. Forensic Analysis using Geological and Geochemical Techniques

    NASA Astrophysics Data System (ADS)

    Hoogewerff, J.

    2009-04-01

    Due to the globalisation of legal (and illegal) trade there is an increasing demand for techniques which can verify the geographical origin and transfer routes of many legal and illegal commodities and products. Although geological techniques have been used in forensic investigations since the emergence of forensics as a science in the late eighteen hundreds, the last decade has seen a marked increase in geo-scientists initiating concept studies using the latest analytical techniques, including studying natural abundance isotope variations, micro analysis with laser ablation ICPMS and geochemical mapping. Most of the concept studies have shown a good potential but uptake by the law enforcement and legal community has been limited due to concerns about the admissibility of the new methods. As an introduction to the UGU2009 session "Forensic Provenancing using Geological and Geochemical Techniques" I will give an overview of the state of the art of forensic geology and the issues that concern the admissibility of geological forensic evidence. I will use examples from the NITECRIME and FIRMS networks, the EU TRACE project and other projects and literature to illustrate the important issues at hand.

  17. UPLC: a preeminent technique in pharmaceutical analysis.

    PubMed

    Kumar, Ashok; Saini, Gautam; Nair, Anroop; Sharma, Rishbha

    2012-01-01

    The pharmaceutical companies today are driven to create novel and more efficient tools to discover, develop, deliver and monitor the drugs. In this contest the development of rapid chromatographic method is crucial for the analytical laboratories. In precedent decade, substantial technological advances have been done in enhancing particle chemistry performance, improving detector design and in optimizing the system, data processors and various controls of chromatographic techniques. When all was blended together, it resulted in the outstanding performance via ultra-high performance liquid chromatography (UPLC), which holds back the principle of HPLC technique. UPLC shows a dramatic enhancement in speed, resolution as well as the sensitivity of analysis by using particle size less than 2 pm and the system is operational at higher pressure, while the mobile phase could be able to run at greater linear velocities as compared to HPLC. This technique is considered as a new focal point in field of liquid chromatographic studies. This review focuses on the basic principle, instrumentation of UPLC and its advantages over HPLC, furthermore, this article emphasizes various pharmaceutical applications of this technique.

  18. Sudden Water Pollution Accidents and Reservoir Emergency Operations: Impact Analysis at Danjiangkou Reservoir.

    PubMed

    Zheng, Hezhen; Shang, Yizi; Duan, Yang; Lei, Xiaohui; Kong, Lingzhong; Wang, Hao

    2017-03-29

    Danjiangkou Reservoir is the source reservoir of the Middle Route of the South-to-North Water Diversion Project (MRP). Any sudden water pollution accident in the reservoir would threaten the water supply of the MRP. We established a 3-D hydrodynamic and water quality model for Danjiangkou Reservoir, and proposed scientific suggestions on the prevention and emergency management for sudden water pollution accidents based on simulated results. Simulations were performed on 20 hypothetical pollutant discharge locations and 3 assumed amounts, in order to model the effect of pollutant spreading under different reservoir operation types. The results showed that both the location and mass of pollution affected water quality; however, different reservoir operation types had little effect. Five joint regulation scenarios, which altered the hydrodynamic processes of water conveyance for the Danjiangkou and Taocha Dams, were considered for controlling pollution dispersion. The results showed that the spread of a pollutant could be effectively controlled through the joint regulation of the two dams and that the collaborative operation of the Danjiangkou and Taocha Dams is critical for ensuring the security of water quality along the MRP.

  19. Analysis of an AP600 intermediate-size loss-of-coolant accident

    SciTech Connect

    Boyack, B.E.; Lime, J.F.

    1995-09-01

    A postulated double-ended guillotine break of an AP600 direct-vessel-injection line has been analyzed. This event is characterized as an intermediate-break loss-of-coolant accident. Most of the insights regarding the response of the AP600 safety systems to the postulated accident are derived from calculations preformed with the TRAC-PF1/MOD2 code. However, complementary insights derived from a scaled experiment conducted in the ROSA facility, as well as insights based upon calculations by other codes, are also presented. Based upon the calculated and experimental results, the AP600 will not experience a core heat up and will reach a safe shutdown state using only safety-class equipment. Only the early part of the long-term cooling period initiated by In-containment Refueling Water Storage Tank injection was evaluated. Thus, the observation that the core is continuously cooled should be verified for the later phase of the long-term cooling period when sump injection and containment cooling processes are important.

  20. Flash Infrared Thermography Contrast Data Analysis Technique

    NASA Technical Reports Server (NTRS)

    Koshti, Ajay

    2014-01-01

    This paper provides information on an IR Contrast technique that involves extracting normalized contrast versus time evolutions from the flash thermography inspection infrared video data. The analysis calculates thermal measurement features from the contrast evolution. In addition, simulation of the contrast evolution is achieved through calibration on measured contrast evolutions from many flat-bottom holes in the subject material. The measurement features and the contrast simulation are used to evaluate flash thermography data in order to characterize delamination-like anomalies. The thermal measurement features relate to the anomaly characteristics. The contrast evolution simulation is matched to the measured contrast evolution over an anomaly to provide an assessment of the anomaly depth and width which correspond to the depth and diameter of the equivalent flat-bottom hole (EFBH) similar to that used as input to the simulation. A similar analysis, in terms of diameter and depth of an equivalent uniform gap (EUG) providing a best match with the measured contrast evolution, is also provided. An edge detection technique called the half-max is used to measure width and length of the anomaly. Results of the half-max width and the EFBH/EUG diameter are compared to evaluate the anomaly. The information provided here is geared towards explaining the IR Contrast technique. Results from a limited amount of validation data on reinforced carbon-carbon (RCC) hardware are included in this paper.

  1. Health effects models for nuclear power plant accident consequence analysis. Part 1, Introduction, integration, and summary: Revision 2

    SciTech Connect

    Evans, J.S.; Abrahmson, S.; Bender, M.A.; Boecker, B.B.; Scott, B.R.; Gilbert, E.S.

    1993-10-01

    This report is a revision of NUREG/CR-4214, Rev. 1, Part 1 (1990), Health Effects Models for Nuclear Power Plant Accident Consequence Analysis. This revision has been made to incorporate changes to the Health Effects Models recommended in two addenda to the NUREG/CR-4214, Rev. 1, Part 11, 1989 report. The first of these addenda provided recommended changes to the health effects models for low-LET radiations based on recent reports from UNSCEAR, ICRP and NAS/NRC (BEIR V). The second addendum presented changes needed to incorporate alpha-emitting radionuclides into the accident exposure source term. As in the earlier version of this report, models are provided for early and continuing effects, cancers and thyroid nodules, and genetic effects. Weibull dose-response functions are recommended for evaluating the risks of early and continuing health effects. Three potentially lethal early effects -- the hematopoietic, pulmonary, and gastrointestinal syndromes are considered. Linear and linear-quadratic models are recommended for estimating the risks of seven types of cancer in adults - leukemia, bone, lung, breast, gastrointestinal, thyroid, and ``other``. For most cancers, both incidence and mortality are addressed. Five classes of genetic diseases -- dominant, x-linked, aneuploidy, unbalanced translocations, and multifactorial diseases are also considered. Data are provided that should enable analysts to consider the timing and severity of each type of health risk.

  2. Weather types and traffic accidents.

    PubMed

    Klaić, Z B

    2001-06-01

    Traffic accident data for the Zagreb area for the 1981-1982 period were analyzed to investigate possible relationships between the daily number of accidents and the weather conditions that occurred for the 5 consecutive days, starting two days before the particular day. In the statistical analysis of low accident days weather type classification developed by Poje was used. For the high accident days a detailed analyses of surface and radiosonde data were performed in order to identify possible front passages. A test for independence by contingency table confirmed that conditional probability of the day with small number of accidents is the highest, provided that one day after it "N" or "NW" weather types occur, while it is the smallest for "N1" and "Bc" types. For the remaining 4 days of the examined periods dependence was not statistically confirmed. However, northern ("N", "NE" and "NW") and anticyclonic ("Vc", "V4", "V3", "V2" and "mv") weather types predominated during 5-days intervals related to the days with small number of accidents. On the contrary, the weather types with cyclonic characteristics ("N1", "N2", "N3", "Bc", "Dol1" and "Dol"), that are generally accompanied by fronts, were the rarest. For 85% days with large number of accidents, which had not been caused by objective circumstances (such as poor visibility, damaged or slippery road etc.), at least one front passage was recorded during the 3-days period, starting one day before the day with large number of accidents.

  3. ROC Analysis of IR Segmentation Techniques.

    DTIC Science & Technology

    1994-12-01

    WrOChtAnattysisoRSgetton Ti’oc aechnique Gpro edo g’bia K lay e;ru Dseciutond LiutnanUA AFIT/GE/ENG/94D-15 ROC Analysis of IR Segmentation Techniques THESIS...classification systems was measured by the percentage of correct decisions, but that "percent correct" does not account for the false-positive and...false-negative errors involved [13]. For example, if 5% of people have a particular disease, then a system can be 95% accurate by calling everyone

  4. An aftermath analysis of the 2014 coal mine accident in Soma, Turkey: Use of risk performance indicators based on historical experience.

    PubMed

    Spada, Matteo; Burgherr, Peter

    2016-02-01

    On the 13th of May 2014 a fire related incident in the Soma coal mine in Turkey caused 301 fatalities and more than 80 injuries. This has been the largest coal mine accident in Turkey, and in the OECD country group, so far. This study investigated if such a disastrous event should be expected, in a statistical sense, based on historical observations. For this purpose, PSI's ENSAD database is used to extract accident data for the period 1970-2014. Four different cases are analyzed, i.e., OECD, OECD w/o Turkey, Turkey and USA. Analysis of temporal trends for annual numbers of accidents and fatalities indicated a non-significant decreasing tendency for OECD and OECD w/o Turkey and a significant one for USA, whereas for Turkey both measures showed an increase over time. The expectation analysis revealed clearly that an event with the consequences of the Soma accident is rather unlikely for OECD, OECD w/o Turkey and USA. In contrast, such a severe accident has a substantially higher expectation for Turkey, i.e. it cannot be considered an extremely rare event, based on historical experience. This indicates a need for improved safety measures and stricter regulations in the Turkish coal mining sector in order to get closer to the rest of OECD.

  5. Supplementary documentation for an Environmental Impact Statement regarding the Pantex Plant: dispersion analysis for postulated accidents

    SciTech Connect

    Dewart, J.M.; Bowen, B.M.; Elder, J.C.

    1982-12-01

    This report documents work performed in support of preparation of an Environmental Impact Statement (EIS) regarding the Department of Energy (DOE) Pantex Plant near Amarillo, Texas. The report covers the calculation of atmospheric dispersion and deposition of plutonium following postulated nonnuclear detonations of nuclear weapons. Downwind total integrated air concentrations and ground deposition values for each postulated accident are presented. The model used to perform these calculations is the DIFOUT model, developed at Sandia National Laboratories in conjunction with Operation Roller Coaster, a field experiment involving sampling and measurements of nuclear material dispersed by four detonations. The DIFOUT model is described along with the detonation cloud sizes, aerosol parameters, and meteorological data used as input data. A verification study of the DIFOUT model has also been performed; the results are presented.

  6. Uncertainty analysis of preclosure accident doses for the Yucca Mountain repository

    SciTech Connect

    Ma, C.W.; Miller, D.D.; Zavoshy, S.J.; Jardine, L.J.

    1990-12-31

    This study presents a generic methodology that can be used to evaluate the uncertainty in the calculated accidental offsite doses at the Yucca Mountain repository during the preclosure period. For demonstration purposes, this methodology is applied to two specific accident scenarios: the first involves a crane dropping an open container with consolidated fuel rods, the second involves container failure during emplacement or removal operations. The uncertainties of thirteen parameters are quantified by various types of probability distributions. The Latin Hypercube Sampling method is used to evaluate the uncertainty of the offsite dose. For the crane-drop scenario with concurrent filter failure, the doses due to the release of airborne fuel particles are calculated to be 0.019, 0.32, and 2.8 rem at confidence levels of 10%, 50%, and 90%, respectively. For the container failure scenario with concurrent filter failure, the 90% confidence-level dose is 0.21 rem. 20 refs., 4 figs., 3 tabs.

  7. Application of Electromigration Techniques in Environmental Analysis

    NASA Astrophysics Data System (ADS)

    Bald, Edward; Kubalczyk, Paweł; Studzińska, Sylwia; Dziubakiewicz, Ewelina; Buszewski, Bogusław

    Inherently trace-level concentration of pollutants in the environment, together with the complexity of sample matrices, place a strong demand on the detection capabilities of electromigration methods. Significant progress is continually being made, widening the applicability of these techniques, mostly capillary zone electrophoresis, micellar electrokinetic chromatography, and capillary electrochromatography, to the analysis of real-world environmental samples, including the concentration sensitivity and robustness of the developed analytical procedures. This chapter covers the recent major developments in the domain of capillary electrophoresis analysis of environmental samples for pesticides, polycyclic aromatic hydrocarbons, phenols, amines, carboxylic acids, explosives, pharmaceuticals, and ionic liquids. Emphasis is made on pre-capillary and on-capillary chromatography and electrophoresis-based concentration of analytes and detection improvement.

  8. TRANSIENT ACCIDENT ANALYSIS OF THE GLOVEBOX SYSTEM IN A LARGE PROCESS ROOM

    SciTech Connect

    Lee, S

    2008-01-11

    Local transient hydrogen concentrations were evaluated inside a large process room when the hydrogen gas was released by three postulated accident scenarios associated with the process tank leakage and fire leading to a loss of gas confinement. The three cases considered in this work were fire in a room, loss of confinement from a process tank, and loss of confinement coupled with fire event. Based on these accident scenarios in a large and unventilated process room, the modeling calculations of the hydrogen migration were performed to estimate local transient concentrations of hydrogen due to the sudden leakage and release from a glovebox system associated with the process tank. The modeling domain represented the major features of the process room including the principal release or leakage source of gas storage system. The model was benchmarked against the literature results for key phenomena such as natural convection, turbulent behavior, gas mixing due to jet entrainment, and radiation cooling because these phenomena are closely related to the gas driving mechanisms within a large air space of the process room. The modeling results showed that at the corner of the process room, the gas concentrations migrated by the Case 2 and Case 3 scenarios reached the set-point value of high activity alarm in about 13 seconds, while the Case 1 scenario takes about 90 seconds to reach the concentration. The modeling results were used to estimate transient radioactive gas migrations in an enclosed process room installed with high activity alarm monitor when the postulated leakage scenarios are initiated without room ventilation.

  9. Biomechanical analysis of protective countermeasures in underride motor vehicle accidents - biomed 2009.

    PubMed

    Kumar, Sri; Enz, Bruce; Ponder, Perry L; Anderson, Bob

    2009-01-01

    Traffic safety has been significantly improved over the past several decades reducing injury and fatality rates. However, there is a paucity of research effort to address the safety issues in underride accidents, specifically the side underride crashes. It is well known that the compromise of occupant space in the vehicle leads to a higher probability of serious or fatal injuries. A better understanding of occupant protection and mechanism of injuries involved in side underride accidents assists in the advancement of safety measures. The present work evaluates the injury potential to occupants during side underride crashes using the car-to-trailer crash methodology. Four crash tests were conducted into the side of a stationary trailer fitted with the side underride guard system (SURG). The SURG used in these tests is 25% lighter than the previous design. A 5th percentile hybrid III female dummy was placed in the driver seat and restrained with the three-point lap and shoulder harness. The anthropometric dummy was instrumented with a head triaxial accelerometer, a chest triaxal accelerometer, a load cell to measure neck force and moment, and a load cell to measure the femur force. The vehicle acceleration was measured using a traxial accelerometer in the rear center tunnel. High speed, standard video and still photos were taken. In all tests, the intrusion was limited to the front structure of the vehicle without any significant compromise to the occupant space. Results indicate that the resultant head and chest accelerations, head injury criterion (HIC), neck force and moment, and femur force were well below the injury tolerance. The present findings support the hypothesis that the SURG not only limits or eliminates the intrusion into the occupant space but also results in biomechanical injury values well below the tolerance limit in motor vehicle crashes.

  10. Analysis of sertraline in postmortem fluids and tissues in 11 aviation accident victims.

    PubMed

    Lewis, Russell J; Angier, Mike K; Williamson, Kelly S; Johnson, Robert D

    2013-05-01

    Sertraline (Zoloft) is a selective serotonin reuptake inhibitor that is a commonly prescribed drug for the treatment of depression, obsessive-compulsive disorder, panic disorder, social anxiety disorder, premenstrual dysphoric disorder and post-traumatic stress disorder. Although the use of sertraline is relatively safe, certain side effects may negatively affect a pilot's performance and become a factor in an aviation accident. The authors' laboratory investigated the distribution of sertraline and its primary metabolite, desmethylsertraline, in various postmortem tissues and fluids obtained from 11 fatal aviation accident cases between 2001 and 2004. Eleven specimen types were analyzed for each case, including blood, urine, vitreous humor, liver, lung, kidney, spleen, muscle, brain, heart and bile. Human specimens were processed utilizing solid-phase extraction, followed by characterization and quantitation employing gas chromatography-mass spectrometry. Whole blood sertraline concentrations obtained from these 11 cases ranged from 0.005 to 0.392 µg/mL. The distribution coefficients of sertraline, expressed as specimen/blood ratio, were as follows: urine, 0.47 ± 0.39 (n = 6); vitreous humor, 0.02 ± 0.01 (n = 4); liver, 74 ± 59 (n = 11); lung, 67 ± 45 (n = 11); kidney, 7.4 ± 5 (n = 11); spleen, 46 ± 45 (n = 10); muscle, 2.1 ± 1.3 (n = 8); brain, 22 ± 14 (n = 10); heart, 9 ± 7 (n = 11); and bile, 36 ± 26 (n = 8). Postmortem distribution coefficients obtained for sertraline had coefficients of variation ranging from 47-99%. This study suggests that sertraline likely undergoes significant postmortem redistribution.

  11. Probabilistic accident consequence uncertainty analysis: Food chain uncertainty assessment. Volume 2: Appendices

    SciTech Connect

    Brown, J.; Goossens, L.H.J.; Kraan, B.C.P.

    1997-06-01

    This volume is the second of a two-volume document that summarizes a joint project by the US Nuclear Regulatory and the Commission of European Communities to assess uncertainties in the MACCS and COSYMA probabilistic accident consequence codes. These codes were developed primarily for estimating the risks presented by nuclear reactors based on postulated frequencies and magnitudes of potential accidents. This two-volume report, which examines mechanisms and uncertainties of transfer through the food chain, is the first in a series of five such reports. A panel of sixteen experts was formed to compile credible and traceable uncertainty distributions for food chain transfer that affect calculations of offsite radiological consequences. Seven of the experts reported on transfer into the food chain through soil and plants, nine reported on transfer via food products from animals, and two reported on both. The expert judgment elicitation procedure and its outcomes are described in these volumes. This volume contains seven appendices. Appendix A presents a brief discussion of the MAACS and COSYMA model codes. Appendix B is the structure document and elicitation questionnaire for the expert panel on soils and plants. Appendix C presents the rationales and responses of each of the members of the soils and plants expert panel. Appendix D is the structure document and elicitation questionnaire for the expert panel on animal transfer. The rationales and responses of each of the experts on animal transfer are given in Appendix E. Brief biographies of the food chain expert panel members are provided in Appendix F. Aggregated results of expert responses are presented in graph format in Appendix G.

  12. Advanced techniques in current signature analysis

    NASA Astrophysics Data System (ADS)

    Smith, S. F.; Castleberry, K. N.

    1992-02-01

    In general, both ac and dc motors can be characterized as weakly nonlinear systems, in which both linear and nonlinear effects occur simultaneously. Fortunately, the nonlinearities are generally well behaved and understood and can be handled via several standard mathematical techniques already well developed in the systems modeling area; examples are piecewise linear approximations and Volterra series representations. Field measurements of numerous motors and motor-driven systems confirm the rather complex nature of motor current spectra and illustrate both linear and nonlinear effects (including line harmonics and modulation components). Although previous current signature analysis (CSA) work at Oak Ridge and other sites has principally focused on the modulation mechanisms and detection methods (AM, PM, and FM), more recent studies have been conducted on linear spectral components (those appearing in the electric current at their actual frequencies and not as modulation sidebands). For example, large axial-flow compressors (approximately 3300 hp) in the US gaseous diffusion uranium enrichment plants exhibit running-speed (approximately 20 Hz) and high-frequency vibrational information (greater than 1 kHz) in their motor current spectra. Several signal-processing techniques developed to facilitate analysis of these components, including specialized filtering schemes, are presented. Finally, concepts for the designs of advanced digitally based CSA units are offered, which should serve to foster the development of much more computationally capable 'smart' CSA instrumentation in the next several years.

  13. Tools for improving safety management in the Norwegian Fishing Fleet occupational accidents analysis period of 1998-2006.

    PubMed

    Aasjord, Halvard L

    2006-01-01

    Reporting of human accidents in the Norwegian Fishing Fleet has always been very difficult because there has been no tradition in making reports on all types of working accidents among fishermen, if the accident does not seem to be very serious or there is no economical incentive to report. Therefore reports are only written when the accidents are serious or if the fisherman is reported sick. Reports about an accident are sent to the insurance company, but another report should also be sent to the Norwegian Maritime Directorate (NMD). Comparing of data from one former insurance company and NMD shows that the real numbers of injuries or serious accidents among Norwegian fishermen could be up to two times more than the numbers reported to NMD. Special analyses of 1690 accidents from the so called PUS-database (NMD) for the period 1998-2002, show that the calculated risk was 23.6 accidents per 1000 man-years. This is quite a high risk level, and most of the accidents in the fishing fleet were rather serious. The calculated risks are highest for fishermen on board the deep sea fleet of trawlers (28.6 accidents per 1000 man-years) and also on the deep sea fleet of purse seiners (28.9 accidents per 1000 man-years). Fatal accidents over a longer period of 51.5 years from 1955 to 2006 are also roughly analysed. These data from SINTEF's own database show that the numbers of fatal accidents have been decreasing over this long period, except for the two periods 1980-84 and 1990-94 where we had some casualties with total losses of larger vessels with the loss of most of the crew, but also many others typical work accidents on smaller vessels. The total numbers of registered Norwegian fishermen and also the numbers of man-years have been drastically reduced over the 51.5 years from 1955 to 2006. The risks of fatal accidents have been very steady over time at a high level, although there has been a marked risk reduction since 1990-94. For the last 8.5-year period of January 1998

  14. Failure Analysis Techniques for the Evaluation of Electrical and Electronic Components in Aircraft Accident Investigations

    DTIC Science & Technology

    1990-08-01

    thick. A widely used plating solution is a high concentration fluoboric acid-peptone system. Other processes use low- fluoboric , nonpetone and a...nonfluoboric organic aryl sulfonic acid process [7.1]. The fluoboric acid processes use lead, tin as Sn2+, fluoboric acid, boric acid and additives...elements such as hydrogen, lithium , boron, cadmium and some of the rare earth elements produce a shadow in a neutron image and are easier to image with

  15. Radiation accidents

    SciTech Connect

    Saenger, E.L.

    1986-09-01

    It is essential that emergency physicians understand ways to manage patients contaminated by radioactive materials and/or exposed to external radiation sources. Contamination accidents require careful surveys to identify the metabolic pathway of the radionuclides to guide prognosis and treatment. The level of treatment required will depend on careful surveys and meticulous decontamination. There is no specific therapy for the acute radiation syndrome. Prophylactic antibodies are desirable. For severely exposed patients treatment is similar to the supportive care given to patients undergoing organ transplantation. For high-dose extremity injury, no methods have been developed to reverse the fibrosing endarteritis that eventually leads to tissue death so frequently found with this type of injury. Although the Three Mile Island episode of March 1979 created tremendous public concern, there were no radiation injuries. The contamination outside the reactor building and the release of radioiodine were negligible. The accidental fuel element meltdown at Chernobyl, USSR, resulted in many cases of acute radiation syndrome. More than 100,000 people were exposed to high levels of radioactive fallout. The general principles outlined here are applicable to accidents of that degree of severity.

  16. Fault tree analysis of fire and explosion accidents for dual fuel (diesel/natural gas) ship engine rooms

    NASA Astrophysics Data System (ADS)

    Guan, Yifeng; Zhao, Jie; Shi, Tengfei; Zhu, Peipei

    2016-09-01

    In recent years, China's increased interest in environmental protection has led to a promotion of energy-efficient dual fuel (diesel/natural gas) ships in Chinese inland rivers. A natural gas as ship fuel may pose dangers of fire and explosion if a gas leak occurs. If explosions or fires occur in the engine rooms of a ship, heavy damage and losses will be incurred. In this paper, a fault tree model is presented that considers both fires and explosions in a dual fuel ship; in this model, dual fuel engine rooms are the top events. All the basic events along with the minimum cut sets are obtained through the analysis. The primary factors that affect accidents involving fires and explosions are determined by calculating the degree of structure importance of the basic events. According to these results, corresponding measures are proposed to ensure and improve the safety and reliability of Chinese inland dual fuel ships.

  17. DEFORM-4: fuel pin characterization and transient response in the SAS4A accident analysis code system

    SciTech Connect

    Miles, K.J.; Hill, D.J.

    1986-01-01

    The DEFORM-4 module is the segment of the SAS4A Accident Analysis Code System that calculates the fuel pin characterization in response to a steady state irradiation history, thereby providing the initial conditions for the transient calculation. The various phenomena considered include fuel porosity migration, fission gas bubble induced swelling, fuel cracking and healing, fission gas release, cladding swelling, and the thermal-mechanical state of the fuel and cladding. In the transient state, the module continues the thermal-mechanical response calculation, including fuel melting and central cavity pressurization, until cladding failure is predicted and one of the failed fuel modules is initiated. Comparisons with experimental data have demonstrated the validity of the modeling approach.

  18. Determination of the end state of the Three Mile Island Unit 2 accident using neutron transport analysis

    SciTech Connect

    Bandini, B.R.; Baratta, A.J. ); Fricke, V.R. )

    1988-06-01

    Since the March 1979 accident, the source range monitors (SRMs) at Three Mile Island Unit 2 (TMI-2) have been reading several orders of magnitude higher than would be expected in a normal shutdown core. A study in which these anomalous SRM readings are analyzed and the cause determined is reported. Here, the DOT 4.3 two-dimensional transport code was used to simulate the SRM response and the response of an axial string of solid-state track recorders by modeling the neutronics of the damaged TMI-2 core. This modeling has indicated the presence of -- 10 tonnes of fuel material in the lower vessel plenum, a condition that was subsequently verified by direct observation. The computational model, the method of cross-section preparation, and an analysis of the various core neutron sources are described, as well as the results obtained from this effort.

  19. Hang-gliding accidents.

    PubMed Central

    Margreiter, R; Lugger, L J

    1978-01-01

    Seventy-five known hang-gliding accidents causing injury to the pilot occurred in the Tyrol during 1973-6. Most occurred in May, June, or September and between 11 am and 3 pm, when unfavourable thermic conditions are most likely. Thirty-four accidents happened during launching, 13 during flight, and 28 during landing, and most were caused by human errors--especially deficient launching technique; incorrect estimation of wind conditions, altitude, and speed; and choice of unfavourable launching and landing sites. Eight pilots were moderately injured, 60 severely (multiply in 24 cases), and seven fatally; fractures of the spine and arms predominated. Six of the 21 skull injuries were fatal. The risk of hang-gliding seems unjustifiably high, and safety precautions and regulations should be adopted to ensure certain standards of training and equipment and to limit flying to favourable sites and times. Images p401-a PMID:624028

  20. Analysis of accident sequences and source terms at treatment and storage facilities for waste generated by US Department of Energy waste management operations

    SciTech Connect

    Mueller, C.; Nabelssi, B.; Roglans-Ribas, J.; Folga, S.; Policastro, A.; Freeman, W.; Jackson, R.; Mishima, J.; Turner, S.

    1996-12-01

    This report documents the methodology, computational framework, and results of facility accident analyses performed for the US Department of Energy (DOE) Waste Management Programmatic Environmental Impact Statement (WM PEIS). The accident sequences potentially important to human health risk are specified, their frequencies assessed, and the resultant radiological and chemical source terms evaluated. A personal-computer-based computational framework and database have been developed that provide these results as input to the WM PEIS for the calculation of human health risk impacts. The WM PEIS addresses management of five waste streams in the DOE complex: low-level waste (LLW), hazardous waste (HW), high-level waste (HLW), low-level mixed waste (LLMW), and transuranic waste (TRUW). Currently projected waste generation rates, storage inventories, and treatment process throughputs have been calculated for each of the waste streams. This report summarizes the accident analyses and aggregates the key results for each of the waste streams. Source terms are estimated, and results are presented for each of the major DOE sites and facilities by WM PEIS alternative for each waste stream. Key assumptions in the development of the source terms are identified. The appendices identify the potential atmospheric release of each toxic chemical or radionuclide for each accident scenario studied. They also discuss specific accident analysis data and guidance used or consulted in this report.

  1. Probabilistic accident consequence uncertainty analysis: Dispersion and deposition uncertainty assessment. Volume 3, Appendices C, D, E, F, and G

    SciTech Connect

    Harper, F.T.; Young, M.L.; Miller, L.A.

    1995-01-01

    The development of two new probabilistic accident consequence codes, MACCS and COSYMA, completed in 1990, estimate the risks presented by nuclear installations based on postulated frequencies and magnitudes of potential accidents. In 1991, the US Nuclear Regulatory Commission (NRC) and the Commission of the European Communities (CEC) began a joint uncertainty analysis of the two codes. The objective was to develop credible and traceable uncertainty distributions for the input variables of the codes. Expert elicitation, developed independently, was identified as the best technology available for developing a library of uncertainty distributions for the selected consequence parameters. The study was formulated jointly and was limited to the current code models and to physical quantities that could be measured in experiments. To validate the distributions generated for the wet deposition input variables, samples were taken from these distributions and propagated through the wet deposition code model along with the Gaussian plume model (GPM) implemented in the MACCS and COSYMA codes. Resulting distributions closely replicated the aggregated elicited wet deposition distributions. Project teams from the NRC and CEC cooperated successfully to develop and implement a unified process for the elaboration of uncertainty distributions on consequence code input parameters. Formal expert judgment elicitation proved valuable for synthesizing the best available information. Distributions on measurable atmospheric dispersion and deposition parameters were successfully elicited from experts involved in the many phenomenological areas of consequence analysis. This volume is the third of a three-volume document describing the project and contains descriptions of the probability assessment principles; the expert identification and selection process; the weighting methods used; the inverse modeling methods; case structures; and summaries of the consequence codes.

  2. Analysis of miners job attendence behavior and its relationship to miners accidents and injuries. Final report. Open file report, 21 September 1982-21 December 1985

    SciTech Connect

    Goodman, P.S.

    1985-10-01

    The report examines coal-miner absenteeism and its relationship to accidents and injuries at underground mines. A total of 19 mines participated in various phases of this 3-year project. Miners at the participating mines ranged in number from 185 to 776. The data consisted of the mines' daily attendance records and detailed interviews with approximately 50 miners from each mine. The interviews contained questions about the miners' satisfaction with various on-the-job and off-the-job factors, their perceptions of the mines' absenteeism policies, the reasons or causes for their own absences, and the miners' demographic characteristics. Accident and injury data from six mines were used in parametric and multiple regression analysis of the absenteeism-accident relationship. The data represented activity during approximately 80,000 miner-days worked. Strategies for reducing absenteeism are discussed.

  3. Advanced analysis techniques for uranium assay

    SciTech Connect

    Geist, W. H.; Ensslin, Norbert; Carrillo, L. A.; Beard, C. A.

    2001-01-01

    Uranium has a negligible passive neutron emission rate making its assay practicable only with an active interrogation method. The active interrogation uses external neutron sources to induce fission events in the uranium in order to determine the mass. This technique requires careful calibration with standards that are representative of the items to be assayed. The samples to be measured are not always well represented by the available standards which often leads to large biases. A technique of active multiplicity counting is being developed to reduce some of these assay difficulties. Active multiplicity counting uses the measured doubles and triples count rates to determine the neutron multiplication (f4) and the product of the source-sample coupling ( C ) and the 235U mass (m). Since the 35U mass always appears in the multiplicity equations as the product of Cm, the coupling needs to be determined before the mass can be known. A relationship has been developed that relates the coupling to the neutron multiplication. The relationship is based on both an analytical derivation and also on empirical observations. To determine a scaling constant present in this relationship, known standards must be used. Evaluation of experimental data revealed an improvement over the traditional calibration curve analysis method of fitting the doubles count rate to the 235Um ass. Active multiplicity assay appears to relax the requirement that the calibration standards and unknown items have the same chemical form and geometry.

  4. Alternative Analysis Techniques for Needs and Needs Documentation Techniques,

    DTIC Science & Technology

    1980-06-20

    economic if business planning *s to Forecasting in the seventies, if it is to be be effective in the seventies.’ Little is report- effective, must include...The strategic business planning and related perspective-tree approach to the identification research and development planning. of threats and...the Seventies: a Trend Analysis for Business Planning (New York: McGraw-Hi Book Com- from either business or technical planning. peny. 1970). FEBRUARY

  5. Episode analysis of deposition of radiocesium from the Fukushima Daiichi nuclear power plant accident.

    PubMed

    Morino, Yu; Ohara, Toshimasa; Watanabe, Mirai; Hayashi, Seiji; Nishizawa, Masato

    2013-03-05

    Chemical transport models played key roles in understanding the atmospheric behaviors and deposition patterns of radioactive materials emitted from the Fukushima Daiichi nuclear power plant after the nuclear accident that accompanied the great Tohoku earthquake and tsunami on 11 March 2011. However, model results could not be sufficiently evaluated because of limited observational data. We assess the model performance to simulate the deposition patterns of radiocesium ((137)Cs) by making use of airborne monitoring survey data for the first time. We conducted ten sensitivity simulations to evaluate the atmospheric model uncertainties associated with key model settings including emission data and wet deposition modules. We found that simulation using emissions estimated with a regional-scale (∼ 500 km) model better reproduced the observed (137)Cs deposition pattern in eastern Japan than simulation using emissions estimated with local-scale (∼ 50 km) or global-scale models. In addition, simulation using a process-based wet deposition module reproduced the observations well, whereas simulation using scavenging coefficients showed large uncertainties associated with empirical parameters. The best-available simulation reproduced the observed (137)Cs deposition rates in high-deposition areas (≥ 10 kBq m(-2)) within 1 order of magnitude and showed that deposition of radiocesium over land occurred predominantly during 15-16, 20-23, and 30-31 March 2011.

  6. Health effects models for nuclear power plant accident consequence analysis: Low LET radiation

    SciTech Connect

    Evans, J.S. . School of Public Health)

    1990-01-01

    This report describes dose-response models intended to be used in estimating the radiological health effects of nuclear power plant accidents. Models of early and continuing effects, cancers and thyroid nodules, and genetic effects are provided. Weibull dose-response functions are recommended for evaluating the risks of early and continuing health effects. Three potentially lethal early effects -- the hematopoietic, pulmonary, and gastrointestinal syndromes -- are considered. In addition, models are included for assessing the risks of several nonlethal early and continuing effects -- including prodromal vomiting and diarrhea, hypothyroidism and radiation thyroiditis, skin burns, reproductive effects, and pregnancy losses. Linear and linear-quadratic models are recommended for estimating cancer risks. Parameters are given for analyzing the risks of seven types of cancer in adults -- leukemia, bone, lung, breast, gastrointestinal, thyroid, and other.'' The category, other'' cancers, is intended to reflect the combined risks of multiple myeloma, lymphoma, and cancers of the bladder, kidney, brain, ovary, uterus and cervix. Models of childhood cancers due to in utero exposure are also developed. For most cancers, both incidence and mortality are addressed. The models of cancer risk are derived largely from information summarized in BEIR III -- with some adjustment to reflect more recent studies. 64 refs., 18 figs., 46 tabs.

  7. "Murder-suicide" or "murder-accident"? Difficulties with the analysis of cases.

    PubMed

    Byard, Roger W; Veldhoen, David; Kobus, Hilton; Heath, Karen

    2010-09-01

    Homicide where a perpetrator is found dead adjacent to the victim usually represents murder-suicide. Two incidents are reported to demonstrate characteristic features in one, and alternative features in the other, that indicate differences in the manner of death. (i) A 37-year-old mother was found dead in a burnt out house with her two young sons in an adjacent bedroom. Deaths were due to incineration and inhalation of products of combustion. (ii) A 39-year-old woman was found stabbed to death in a burnt out house with her 39-year-old de facto partner deceased from the combined effects of incineration and inhalation of products of combustion. The first incident represented a typical murder-suicide, however, in the second incident, the perpetrator had tried to escape through a window and had then sought refuge in a bathroom under a running shower. Murder-accident rather than murder-suicide may therefore be a more accurate designation for such cases.

  8. Spatiotemporal Analysis for Wildlife-Vehicle Based on Accident Statistics of the County Straubing-Bogen in Lower Bavaria

    NASA Astrophysics Data System (ADS)

    Pagany, R.; Dorner, W.

    2016-06-01

    During the last years the numbers of wildlife-vehicle-collisions (WVC) in Bavaria increased considerably. Despite the statistical registration of WVC and preventive measures at areas of risk along the roads, the number of such accidents could not be contained. Using geospatial analysis on WVC data of the last five years for county Straubing-Bogen, Bavaria, a small-scale methodology was found to analyse the risk of WVC along the roads in the investigated area. Various indicators were examined, which may be related to WVC. The risk depends on the time of the day and year which shows correlations in turn to the traffic density and wildlife population. Additionally the location of the collision depends on the species and on different environmental parameters. Accidents seem to correlate with the land use left and right of the street. Land use data and current vegetation were derived from remote sensing data, providing information of the general land use, also considering the vegetation period. For this a number of hot spots was selected to identify potential dependencies between land use, vegetation and season. First results from these hotspots show, that WVCs do not only depend on land use, but may show a correlation with the vegetation period. With regard to agriculture and seasonal as well as annual changes this indicates that warnings will fail due to their static character in contrast to the dynamic situation of land use and resulting risk for WVCs. This shows that there is a demand for remote sensing data with a high spatial and temporal resolution as well as a methodology to derive WVC warnings considering land use and vegetation. With remote sensing data, it could become possible to classify land use and calculate risk levels for WVC. Additional parameters, derived from remote sensed data that could be considered are relief and crops as well as other parameters such as ponds, natural and infrastructural barriers that could be related to animal behaviour and

  9. Supplemental analysis of accident sequences and source terms for waste treatment and storage operations and related facilities for the US Department of Energy waste management programmatic environmental impact statement

    SciTech Connect

    Folga, S.; Mueller, C.; Nabelssi, B.; Kohout, E.; Mishima, J.

    1996-12-01

    This report presents supplemental information for the document Analysis of Accident Sequences and Source Terms at Waste Treatment, Storage, and Disposal Facilities for Waste Generated by US Department of Energy Waste Management Operations. Additional technical support information is supplied concerning treatment of transuranic waste by incineration and considering the Alternative Organic Treatment option for low-level mixed waste. The latest respirable airborne release fraction values published by the US Department of Energy for use in accident analysis have been used and are included as Appendix D, where respirable airborne release fraction is defined as the fraction of material exposed to accident stresses that could become airborne as a result of the accident. A set of dominant waste treatment processes and accident scenarios was selected for a screening-process analysis. A subset of results (release source terms) from this analysis is presented.

  10. Commuting accidents in the German chemical industry.

    PubMed

    Zepf, Kirsten Isabel; Letzel, Stephan; Voelter-Mahlknecht, Susanne; Wriede, Ulrich; Husemann, Britta; Escobar Pinzón, Luis Carlos

    2010-01-01

    Due to accident severity and the extent of claim payments commuting accidents are a significant expense factor in the German industry. Therefore the aim of the present study was the identification of risk factors for commuting accidents in a German chemical company. A retrospective analysis of commuting accidents recorded between 1990 and 2003 was conducted in a major chemical company in Germany. A logistic regression-model was calculated in order to determine factors influencing the duration of work inability as a result of commuting accidents. The analysed data included 5,484 employees with commuting accidents. Cars (33.1%) and bicycles (30.5%) were the most common types of vehicles used by commuters who had an accident. The highest number of commuting accidents was observed in the age group under 26 yr. Accidents on the route from the work site to the worker's residence were less frequently observed, but they caused longer periods of work inability than accidents on the way to the work site. The longest periods of work inability were found in the groups of motorcyclists and older employees. The present study identifies specific groups at risk for commuting accidents. The data of the present investigation also underline the need for developing group specific prevention strategies.

  11. Comparing the Identification of Recommendations by Different Accident Investigators Using a Common Methodology

    NASA Technical Reports Server (NTRS)

    Johnson, Chris W.; Oltedal, H. A.; Holloway, C. M.

    2012-01-01

    Accident reports play a key role in the safety of complex systems. These reports present the recommendations that are intended to help avoid any recurrence of past failures. However, the value of these findings depends upon the causal analysis that helps to identify the reasons why an accident occurred. Various techniques have been developed to help investigators distinguish root causes from contributory factors and contextual information. This paper presents the results from a study into the individual differences that can arise when a group of investigators independently apply the same technique to identify the causes of an accident. This work is important if we are to increase the consistency and coherence of investigations following major accidents.

  12. Health effects model for nuclear power plant accident consequence analysis. Part I. Introduction, integration, and summary. Part II. Scientific basis for health effects models

    SciTech Connect

    Evans, J.S.; Moeller, D.W.; Cooper, D.W.

    1985-07-01

    Analysis of the radiological health effects of nuclear power plant accidents requires models for predicting early health effects, cancers and benign thyroid nodules, and genetic effects. Since the publication of the Reactor Safety Study, additional information on radiological health effects has become available. This report summarizes the efforts of a program designed to provide revised health effects models for nuclear power plant accident consequence modeling. The new models for early effects address four causes of mortality and nine categories of morbidity. The models for early effects are based upon two parameter Weibull functions. They permit evaluation of the influence of dose protraction and address the issue of variation in radiosensitivity among the population. The piecewise-linear dose-response models used in the Reactor Safety Study to predict cancers and thyroid nodules have been replaced by linear and linear-quadratic models. The new models reflect the most recently reported results of the follow-up of the survivors of the bombings of Hiroshima and Nagasaki and permit analysis of both morbidity and mortality. The new models for genetic effects allow prediction of genetic risks in each of the first five generations after an accident and include information on the relative severity of various classes of genetic effects. The uncertainty in modeloling radiological health risks is addressed by providing central, upper, and lower estimates of risks. An approach is outlined for summarizing the health consequences of nuclear power plant accidents. 298 refs., 9 figs., 49 tabs.

  13. Source term and radiological consequences of the Chernobyl accident

    SciTech Connect

    Mourad, R.; Snell, V.

    1987-01-01

    The objective of this work is to assess the source term and to evaluate the maximum hypothetical individual doses in European countries (including the Soviet Union) from the Chernobyl accident through the analyses of measurements of meteorological data, radiation fields, and airborne and deposited activity in these countries. Applying this information to deduce the source term involves a reversal of the techniques of nuclear accident analysis, which estimate the off-site consequences of postulated accidents. In this study the authors predict the quantities of radionuclides that, if released at Chernobyl and following the calculated trajectories, would explain and unify the observed radiation levels and radionuclide concentrations as measured by European countries and the Soviet Union. The simulation uses the PEAR microcomputer program following the methodology described in Canadian Standards Association standard N288.2. The study was performed before the Soviets published their estimate of the source term and the two results are compared.

  14. Laser-based flow cytometric analysis of genotoxicity of humans exposed to ionizing radiation during the Chernobyl accident

    SciTech Connect

    Jensen, R.H.; Bigbee, W.L.; Langlois, R.G.; Grant, S.G. ); Pleshanov, P.G. ); Chirkov, A.A. ); Pilinskaya, M.A. )

    1990-09-12

    An analytical technique has been developed that allows laser-based flow cytometric measurement of the frequency of red blood cells that have lost allele-specific expression of a cell surface antigen due to genetic toxicity in bone marrow precursor cells. Previous studies demonstrated a correlation of such effects with the exposure of each individual to mutagenic phenomena, such as ionizing radiation, and the effects can persist for the lifetime of each individual. During the emergency response to the nuclear power plant accident at Chernobyl, Ukraine, USSR, a number of people were exposed to whole body doses of ionizing radiation. Some of these individuals were tested with this laser-based assay and found to express a dose-dependent increase in the frequency of variant red blood cells that appears to be a persistent biological effect. All data indicate that this assay might well be used as a biodosimeter to estimate radiation dose and also as an element to be used for estimating the risk of each individual to develop cancer due to radiation exposure. 17 refs., 5 figs.

  15. Numerical modeling techniques for flood analysis

    NASA Astrophysics Data System (ADS)

    Anees, Mohd Talha; Abdullah, K.; Nawawi, M. N. M.; Ab Rahman, Nik Norulaini Nik; Piah, Abd. Rahni Mt.; Zakaria, Nor Azazi; Syakir, M. I.; Mohd. Omar, A. K.

    2016-12-01

    Topographic and climatic changes are the main causes of abrupt flooding in tropical areas. It is the need to find out exact causes and effects of these changes. Numerical modeling techniques plays a vital role for such studies due to their use of hydrological parameters which are strongly linked with topographic changes. In this review, some of the widely used models utilizing hydrological and river modeling parameters and their estimation in data sparse region are discussed. Shortcomings of 1D and 2D numerical models and the possible improvements over these models through 3D modeling are also discussed. It is found that the HEC-RAS and FLO 2D model are best in terms of economical and accurate flood analysis for river and floodplain modeling respectively. Limitations of FLO 2D in floodplain modeling mainly such as floodplain elevation differences and its vertical roughness in grids were found which can be improve through 3D model. Therefore, 3D model was found to be more suitable than 1D and 2D models in terms of vertical accuracy in grid cells. It was also found that 3D models for open channel flows already developed recently but not for floodplain. Hence, it was suggested that a 3D model for floodplain should be developed by considering all hydrological and high resolution topographic parameter's models, discussed in this review, to enhance the findings of causes and effects of flooding.

  16. Magnetic Analysis Techniques Applied to Desert Varnish

    NASA Technical Reports Server (NTRS)

    Schmidgall, E. R.; Moskowitz, B. M.; Dahlberg, E. D.; Kuhlman, K. R.

    2003-01-01

    Desert varnish is a black or reddish coating commonly found on rock samples from arid regions. Typically, the coating is very thin, less than half a millimeter thick. Previous research has shown that the primary components of desert varnish are silicon oxide clay minerals (60%), manganese and iron oxides (20-30%), and trace amounts of other compounds [1]. Desert varnish is thought to originate when windborne particles containing iron and manganese oxides are deposited onto rock surfaces where manganese oxidizing bacteria concentrate the manganese and form the varnish [4,5]. If desert varnish is indeed biogenic, then the presence of desert varnish on rock surfaces could serve as a biomarker, indicating the presence of microorganisms. This idea has considerable appeal, especially for Martian exploration [6]. Magnetic analysis techniques have not been extensively applied to desert varnish. The only previous magnetic study reported that based on room temperature demagnetization experiments, there were noticeable differences in magnetic properties between a sample of desert varnish and the substrate sandstone [7]. Based upon the results of the demagnetization experiments, the authors concluded that the primary magnetic component of desert varnish was either magnetite (Fe3O4) or maghemite ( Fe2O3).

  17. Injury Severity and Mortality of Adult Zebra Crosswalk and Non-Zebra Crosswalk Road Crossing Accidents: A Cross-Sectional Analysis

    PubMed Central

    Pfortmueller, Carmen A.; Marti, Mariana; Kunz, Mirco; Lindner, Gregor; Exadaktylos, Aristomenis K.

    2014-01-01

    Principals Over a million people worldwide die each year from road traffic injuries and more than 10 million sustain permanent disabilities. Many of these victims are pedestrians. The present retrospective study analyzes the severity and mortality of injuries suffered by adult pedestrians, depending on whether they used a zebra crosswalk. Methods Our retrospective data analysis covered adult patients admitted to our emergency department (ED) between 1 January 2000 and 31 December 2012 after being hit by a vehicle while crossing the road as a pedestrian. Patients were identified by using a string term. Medical, police and ambulance records were reviewed for data extraction. Results A total of 347 patients were eligible for study inclusion. Two hundred and three (203; 58.5%) patients were on a zebra crosswalk and 144 (41.5%) were not. The mean ISS (injury Severity Score) was 12.1 (SD 14.7, range 1-75). The vehicles were faster in non-zebra crosswalk accidents (47.7 km/n, versus 41.4 km/h, p<0.027). The mean ISS score was higher in patients with non-zebra crosswalk accidents; 14.4 (SD 16.5, range 1–75) versus 10.5 (SD13.14, range 1–75) (p<0.019). Zebra crosswalk accidents were associated with less risk of severe injury (OR 0.61, 95% CI 0.38–0.98, p<0.042). Accidents involving a truck were associated with increased risk of severe injury (OR 3.53, 95%CI 1.21–10.26, p<0.02). Conclusion Accidents on zebra crosswalks are more common than those not on zebra crosswalks. The injury severity of non-zebra crosswalk accidents is significantly higher than in patients with zebra crosswalk accidents. Accidents involving large vehicles are associated with increased risk of severe injury. Further prospective studies are needed, with detailed assessment of motor vehicle types and speed. PMID:24595100

  18. Function Analysis and Decomposistion using Function Analysis Systems Technique

    SciTech Connect

    J. R. Wixson

    1999-06-01

    The "Father of Value Analysis", Lawrence D. Miles, was a design engineer for General Electric in Schenectady, New York. Miles developed the concept of function analysis to address difficulties in satisfying the requirements to fill shortages of high demand manufactured parts and electrical components during World War II. His concept of function analysis was further developed in the 1960s by Charles W. Bytheway, a design engineer at Sperry Univac in Salt Lake City, Utah. Charles Bytheway extended Mile's function analysis concepts and introduced the methodology called Function Analysis Systems Techniques (FAST) to the Society of American Value Engineers (SAVE) at their International Convention in 1965 (Bytheway 1965). FAST uses intuitive logic to decompose a high level, or objective function into secondary and lower level functions that are displayed in a logic diagram called a FAST model. Other techniques can then be applied to allocate functions to components, individuals, processes, or other entities that accomplish the functions. FAST is best applied in a team setting and proves to be an effective methodology for functional decomposition, allocation, and alternative development.

  19. Function Analysis and Decomposistion using Function Analysis Systems Technique

    SciTech Connect

    Wixson, James Robert

    1999-06-01

    The "Father of Value Analysis", Lawrence D. Miles, was a design engineer for General Electric in Schenectady, New York. Miles developed the concept of function analysis to address difficulties in satisfying the requirements to fill shortages of high demand manufactured parts and electrical components during World War II. His concept of function analysis was further developed in the 1960s by Charles W. Bytheway, a design engineer at Sperry Univac in Salt Lake City, Utah. Charles Bytheway extended Mile's function analysis concepts and introduced the methodology called Function Analysis Systems Technique (FAST) to the Society of American Value Engineers (SAVE) at their International Convention in 1965 (Bytheway 1965). FAST uses intuitive logic to decompose a high level, or objective function into secondary and lower level functions that are displayed in a logic diagram called a FAST model. Other techniques can then be applied to allocate functions to components, individuals, processes, or other entities that accomplish the functions. FAST is best applied in a team setting and proves to be an effective methodology for functional decomposition, allocation, and alternative development.

  20. Underreporting of maritime accidents to vessel accident databases.

    PubMed

    Hassel, Martin; Asbjørnslett, Bjørn Egil; Hole, Lars Petter

    2011-11-01

    Underreporting of maritime accidents is a problem not only for authorities trying to improve maritime safety through legislation, but also to risk management companies and other entities using maritime casualty statistics in risk and accident analysis. This study collected and compared casualty data from 01.01.2005 to 31.12.2009, from IHS Fairplay and the maritime authorities from a set of nations. The data was compared to find common records, and estimation of the true number of occurred accidents was performed using conditional probability given positive dependency between data sources, several variations of the capture-recapture method, calculation of best case scenario assuming perfect reporting, and scaling up a subset of casualty information from a marine insurance statistics database. The estimated upper limit reporting performance for the selected flag states ranged from 14% to 74%, while the corresponding estimated coverage of IHS Fairplay ranges from 4% to 62%. On average the study results document that the number of unreported accidents makes up roughly 50% of all occurred accidents. Even in a best case scenario, only a few flag states come close to perfect reporting (94%). The considerable scope of underreporting uncovered in the study, indicates that users of statistical vessel accident data should assume a certain degree of underreporting, and adjust their analyses accordingly. Whether to use correction factors, a safety margin, or rely on expert judgment, should be decided on a case by case basis.

  1. 48 CFR 15.404-1 - Proposal analysis techniques.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... are: I Price Analysis, II Quantitative Techniques for Contract Pricing, III Cost Analysis, IV Advanced... obtained through market research for the same or similar items. (vii) Analysis of data other than...

  2. 48 CFR 15.404-1 - Proposal analysis techniques.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... are: I Price Analysis, II Quantitative Techniques for Contract Pricing, III Cost Analysis, IV Advanced... obtained through market research for the same or similar items. (vii) Analysis of data other than...

  3. A review of monitoring, sampling and analysis of reactor coolant, reactor containment atmosphere and airborne reactor effluents in post accident concentrations

    SciTech Connect

    Hull, A.P.; White, J.R.; Knox, W.H.

    1986-01-01

    A post-implementation review has been made in NRC Region I of the post-accident sampling systems (PASS), the gaseous effluent monitors, and the provisions for sampling effluent particulates and radioiodines which were required by the NRC subsequent to the TMI-2 accident (NUREG-0737). Prefabricated PASS systems were predominant. Problems included insufficient purge times, inadequate separation of dissolved gases, excessive dilution and the accuracy of analytical techniques in the presence of interferences. Microprocessor-controlled high-range gas monitors with integral provisions for sampling particulates and radioiodines in high concentrations were widely used. Calibration information was generally insufficient for the unambiguous conversion of monitor readings to release rates for a varying postaccident mixture of radiogases. The referenced sampling guidance (ANSI-N 13.1-1969) was inappropriate for the long sampling lines customarily used. Generic research is needed to establish the behavior of particulates and radioiodines in these lines.

  4. Paragliding accidents in remote areas.

    PubMed

    Fasching, G; Schippinger, G; Pretscher, R

    1997-08-01

    Paragliding is an increasingly popular hobby, as people try to find new and more adventurous activities. However, there is an increased and inherent danger with this sport. For this reason, as well as the inexperience of many operators, injuries occur frequently. This retrospective study centers on the helicopter rescue of 70 individuals in paragliding accidents. All histories were examined, and 43 patients answered a questionnaire. Nineteen (42%) pilots were injured when taking off, 20 (44%) during the flight, and six (13%) when landing. Routine and experience did not affect the prevalence of accident. Analysis of the causes of accident revealed pilot errors in all but three cases. In 34 rescue operations a landing of the helicopter near the site of the accident was possible. Half of the patients had to be rescued by a cable winch or a long rope fixed to the helicopter. Seven (10%) of the pilots suffered multiple trauma, 38 (54%) had injuries of the lower extremities, and 32 (84%) of them sustained fractures. Injuries to the spine were diagnosed in 34 cases with a fracture rate of 85%. One patient had an incomplete paraplegia. Injuries to the head occurred in 17 patients. No paraglider pilot died. The average hospitalization was 22 days, and average time of working inability was 14 weeks. Fourteen (34%) patients suffered from a permanent damage to their nerves or joints. Forty-three percent of the paragliders continued their sport despite the accident; two of them had another accident. An improved training program is necessary to lower the incidence of paragliding accidents. Optimal equipment to reduce injuries in case of accidents is mandatory. The helicopter emergency physician must perform a careful examination, provide stabilization of airways and circulation, give analgesics, splint fractured extremities, and transport the victim on a vacuum mattress to the appropriate hospital.

  5. Characteristic variation and original analysis of emergent water source pollution accidents in China between 1985 and 2013.

    PubMed

    Qu, Jianhua; Meng, Xianlin; Ye, Xiuqing; You, Hong

    2016-10-01

    China has suffered various water source pollution incidents in the past decades, which have resulted in severe threats to the safety of the water supply for millions of residents. From the aspects of quantity fluctuation, temporal volatility, regional inequality, pollutant category variation, and accident type differences, this study first characterizes the current status of water source contaminations in China by analyzing 340 pollution events for the period spanning from 1985 to 2013. The results show a general increase in the number of accidents during the period 1985-2006 and then a rapid decline starting in 2007. Spring and summer are high-incidence seasons for pollution, and the accident rate in developed southeastern coastal areas is far higher than that in the northwestern regions. Hazardous chemicals and petroleum are the most frequently occurring pollutants, whereas heavy metals and tailings are becoming emerging contaminants during occasional pollutions. Most of the accidents that occurred before 2005 were blamed on illegal emissions or traffic accidents; however, leakage in production has gradually become a major accident type in the past decade. Then, in combination with government actions and policy constraints, this paper explores the deep inducements and offers valuable insight into measures that should be taken to ensure future prevention and mitigation of emergent source water pollution.

  6. Temporal uncertainty analysis of human errors based on interrelationships among multiple factors: a case of Minuteman III missile accident.

    PubMed

    Rong, Hao; Tian, Jin; Zhao, Tingdi

    2016-01-01

    In traditional approaches of human reliability assessment (HRA), the definition of the error producing conditions (EPCs) and the supporting guidance are such that some of the conditions (especially organizational or managerial conditions) can hardly be included, and thus the analysis is burdened with incomprehensiveness without reflecting the temporal trend of human reliability. A method based on system dynamics (SD), which highlights interrelationships among technical and organizational aspects that may contribute to human errors, is presented to facilitate quantitatively estimating the human error probability (HEP) and its related variables changing over time in a long period. Taking the Minuteman III missile accident in 2008 as a case, the proposed HRA method is applied to assess HEP during missile operations over 50 years by analyzing the interactions among the variables involved in human-related risks; also the critical factors are determined in terms of impact that the variables have on risks in different time periods. It is indicated that both technical and organizational aspects should be focused on to minimize human errors in a long run.

  7. Analysis of Sodium Fire in the Containment Building of Prototype Fast Breeder Reactor Under the Scenario of Core Disruptive Accident

    SciTech Connect

    Rao, P.M.; Kasinathan, N.; Kannan, S.E.

    2006-07-01

    The potential for sodium release to reactor containment building from reactor assembly during Core Disruptive Accident (CDA) in Fast Breeder Reactors (FBR) is an important safety issue with reference to the structural integrity of Reactor Containment Building (RCB). For Prototype Fast Breeder Reactor (PFBR), the estimated sodium release under a CDA of 100 MJ energy release is 350 kg. The ejected sodium reacts easily with air in RCB and causes temperature and pressure rise in the RCB. For estimating the severe thermal consequences in RCB, different modes of sodium fires like pool and spray fires were analyzed by using SOFIRE -- II and NACOM sodium fire computer codes. Effects of important parameters like amount of sodium, area of pool, containment air volume and oxygen concentration have been investigated. A peak pressure rise of 7.32 kPa is predicted by SOFIRE II code for 350 kg sodium pool fire in 86,000 m{sup 3} RCB volume. Under sodium release as spray followed by unburnt sodium as pool fire mode analysis, the estimated pressure rise is 5.85 kPa in the RCB. In the mode of instantaneous combustion of sodium, the estimated peak pressure rise is 13 kPa. (authors)

  8. TRUMP-BD: A computer code for the analysis of nuclear fuel assemblies under severe accident conditions

    SciTech Connect

    Lombardo, N.J.; Marseille, T.J.; White, M.D.; Lowery, P.S.

    1990-06-01

    TRUMP-BD (Boil Down) is an extension of the TRUMP (Edwards 1972) computer program for the analysis of nuclear fuel assemblies under severe accident conditions. This extension allows prediction of the heat transfer rates, metal-water oxidation rates, fission product release rates, steam generation and consumption rates, and temperature distributions for nuclear fuel assemblies under core uncovery conditions. The heat transfer processes include conduction in solid structures, convection across fluid-solid boundaries, and radiation between interacting surfaces. Metal-water reaction kinetics are modeled with empirical relationships to predict the oxidation rates of steam-exposed Zircaloy and uranium metal. The metal-water oxidation models are parabolic in form with an Arrhenius temperature dependence. Uranium oxidation begins when fuel cladding failure occurs; Zircaloy oxidation occurs continuously at temperatures above 13000{degree}F when metal and steam are available. From the metal-water reactions, the hydrogen generation rate, total hydrogen release, and temporal and spatial distribution of oxide formations are computed. Consumption of steam from the oxidation reactions and the effect of hydrogen on the coolant properties is modeled for independent coolant flow channels. Fission product release from exposed uranium metal Zircaloy-clad fuel is modeled using empirical time and temperature relationships that consider the release to be subject to oxidation and volitization/diffusion ( bake-out'') release mechanisms. Release of the volatile species of iodine (I), tellurium (Te), cesium (Ce), ruthenium (Ru), strontium (Sr), zirconium (Zr), cerium (Cr), and barium (Ba) from uranium metal fuel may be modeled.

  9. Cochlear implant simulator for surgical technique analysis

    NASA Astrophysics Data System (ADS)

    Turok, Rebecca L.; Labadie, Robert F.; Wanna, George B.; Dawant, Benoit M.; Noble, Jack H.

    2014-03-01

    Cochlear Implant (CI) surgery is a procedure in which an electrode array is inserted into the cochlea. The electrode array is used to stimulate auditory nerve fibers and restore hearing for people with severe to profound hearing loss. The primary goals when placing the electrode array are to fully insert the array into the cochlea while minimizing trauma to the cochlea. Studying the relationship between surgical outcome and various surgical techniques has been difficult since trauma and electrode placement are generally unknown without histology. Our group has created a CI placement simulator that combines an interactive 3D visualization environment with a haptic-feedback-enabled controller. Surgical techniques and patient anatomy can be varied between simulations so that outcomes can be studied under varied conditions. With this system, we envision that through numerous trials we will be able to statistically analyze how outcomes relate to surgical techniques. As a first test of this system, in this work, we have designed an experiment in which we compare the spatial distribution of forces imparted to the cochlea in the array insertion procedure when using two different but commonly used surgical techniques for cochlear access, called round window and cochleostomy access. Our results suggest that CIs implanted using round window access may cause less trauma to deeper intracochlear structures than cochleostomy techniques. This result is of interest because it challenges traditional thinking in the otological community but might offer an explanation for recent anecdotal evidence that suggests that round window access techniques lead to better outcomes.

  10. [Accidents in travellers - the hidden epidemic].

    PubMed

    Walz, Alexander; Hatz, Christoph

    2013-06-01

    The risk of malaria and other communicable diseases is well addressed in pre-travel advice. Accidents are usually less discussed. Thus, we aimed at assessing accident figures for the Swiss population, based on data of the register from 2004 to 2008 of the largest Swiss accident insurance organization (SUVA). More than 139'000 accidents over 5 years showed that 65 % of the accidents overseas are injuries, and 24 % are caused by poisoning or harm by cold, heat or air pressure. Most accidents happened during leisure activities or sports. More than one third of the non-lethal and more than 50 % of the fatal accidents happened in Asia. More than three-quarters of non-lethal accidents take place in people between 25 and 54 years. One out of 74 insured persons has an accident abroad per year. Despite of many analysis short-comings of the data set with regard to overseas travel, the figures document the underestimated burden of disease caused by accidents abroad and should affect the given pre-health advice.

  11. A working man`s analysis of incidents and accidents with explosives at the Los Alamos National Laboratory, 1946--1997

    SciTech Connect

    Ramsay, J.B.; Goldie, R.H.

    1998-12-31

    At the inception of the Laboratory hectic and intense work was the norm during the development of the atomic bombs. After the war the development of other weapons for the Cold War again contributed to an intense work environment. Formal Standard Operating Procedures (SOPs) were not required at that time. However, the occurrence of six fatalities in 1959 during the development of a new high-energy plastic bonded explosive (94% HMX) forced the introduction SOPs. After an accident at the Department of Energy (DOE) plant at Amarillo, TX in 1977, the DOE promulgated the Department wide DOE Explosives Safety Manual. Table 1 outlines the history of the introduction of SOPs and the DOE Explosives Safety Manual. Many of the rules and guidelines presented in these documents were developed and introduced as the result of an incident or accident. However, many of the current staff are not familiar with the background of the development. To preserve as much of this knowledge as possible, they are collecting documentation on incidents and accidents involving energetic materials at Los Alamos. Formal investigations of serious accidents elucidate the multiple causes that contributed to accidents. These reports are generally buried in a file and, and are not read by more recent workers. Reports involving fatalities at Los Alamos before 1974 were withheld from the general employee. Also, these documents contain much detail and analysis that is not of interest to the field worker. The authors have collected the documents describing 116 incidents and have analyzed the contributing factors as viewed from the standpoint of the individual operator. All the incidents occurred at the Los Alamos National Laboratory and involved energetic materials in some manner, though not all occurred within the explosive handling groups. Most accidents are caused by multiple contributing factors. They have attempted to select the one or two factors that they consider as the most important relative to the

  12. Kinetics Parameters of VVER-1000 Core with 3 MOX Lead Test Assemblies To Be Used for Accident Analysis Codes

    SciTech Connect

    Pavlovitchev, A.M.

    2000-03-08

    The present work is a part of Joint U.S./Russian Project with Weapons-Grade Plutonium Disposition in VVER Reactor and presents the neutronics calculations of kinetics parameters of VVER-1000 core with 3 introduced MOX LTAs. MOX LTA design has been studied in [1] for two options of MOX LTA: 100% plutonium and of ''island'' type. As a result, zoning i.e. fissile plutonium enrichments in different plutonium zones, has been defined. VVER-1000 core with 3 introduced MOX LTAs of chosen design has been calculated in [2]. In present work, the neutronics data for transient analysis codes (RELAP [3]) has been obtained using the codes chain of RRC ''Kurchatov Institute'' [5] that is to be used for exploitation neutronics calculations of VVER. Nowadays the 3D assembly-by-assembly code BIPR-7A and 2D pin-by-pin code PERMAK-A, both with the neutronics constants prepared by the cell code TVS-M, are the base elements of this chain. It should be reminded that in [6] TVS-M was used only for the constants calculations of MOX FAs. In current calculations the code TVS-M has been used both for UOX and MOX fuel constants. Besides, the volume of presented information has been increased and additional explications have been included. The results for the reference uranium core [4] are presented in Chapter 2. The results for the core with 3 MOX LTAs are presented in Chapter 3. The conservatism that is connected with neutronics parameters and that must be taken into account during transient analysis calculations, is discussed in Chapter 4. The conservative parameters values are considered to be used in 1-point core kinetics models of accident analysis codes.

  13. Analysis of avalanche risk factors in backcountry terrain based on usage frequency and accident data in Switzerland

    NASA Astrophysics Data System (ADS)

    Techel, F.; Zweifel, B.; Winkler, K.

    2015-09-01

    Recreational activities in snow-covered mountainous terrain in the backcountry account for the vast majority of avalanche accidents. Studies analyzing avalanche risk mostly rely on accident statistics without considering exposure (or the elements at risk), i.e., how many, when and where people are recreating, as data on recreational activity in the winter mountains are scarce. To fill this gap, we explored volunteered geographic information on two social media mountaineering websites - bergportal.ch and camptocamp.org. Based on these data, we present a spatiotemporal pattern of winter backcountry touring activity in the Swiss Alps and compare this with accident statistics. Geographically, activity was concentrated in Alpine regions relatively close to the main Swiss population centers in the west and north. In contrast, accidents occurred equally often in the less-frequented inner-alpine regions. Weekends, weather and avalanche conditions influenced the number of recreationists, while the odds to be involved in a severe avalanche accident did not depend on weekends or weather conditions. However, the likelihood of being involved in an accident increased with increasing avalanche danger level, but also with a more unfavorable snowpack containing persistent weak layers (also referred to as an old snow problem). In fact, the most critical situation for backcountry recreationists and professionals occurred on days and in regions when both the avalanche danger was critical and when the snowpack contained persistent weak layers. The frequently occurring geographical pattern of a more unfavorable snowpack structure also explains the relatively high proportion of accidents in the less-frequented inner-alpine regions. These results have practical implications: avalanche forecasters should clearly communicate the avalanche danger and the avalanche problem to the backcountry user, particularly if persistent weak layers are of concern. Professionals and recreationists, on the

  14. Preliminary Accident Analysis for Construction and Operation of the Chornobyl New Safety Confinement

    SciTech Connect

    Batiy, Valeriy; Rubezhansky, Yruiy; Rudko, Vladimir; shcherbin, vladimir; Yegorov, V; Schmieman, Eric A.; Timmins, Douglas C.

    2005-08-08

    Analysis of potential exposure of personal and population during construction and exploitation of the New Safe Confinement was made. Scenarios of hazard event development were ranked. It is shown, that as a whole construction and exploitation of the NSC are in accordance with actual radiation safety norms of Ukraine.

  15. Identification of victims of the 1998 Taoyuan Airbus crash accident using DNA analysis.

    PubMed

    Hsu, C M; Huang, N E; Tsai, L C; Kao, L G; Chao, C H; Linacre, A; Lee, J C

    1999-01-01

    In February 1998 a civilian aeroplane carrying 196 individuals crashed in Taiwan and killed another 6 people on the ground. Although there were dental and medical records, fingerprints, photographic evidence and personal effects to identify some of the victims, DNA analysis was required to further identify severely damaged remains. From the 202 people known to have perished in the plane crash, a total of 685 fragments of human remains were subjected to DNA analysis. The analysis was carried out using nine microsatellite loci, plus amelogenin to cluster the 685 fragments into 202 groups, accounting for all the victims. To establish genetic relatedness of the victims to other victims and living relatives, additional DNA loci were used. In this case the paternity index was increased by using HLA DQA1 plus Polymarker. The same 16 DNA loci were used to test blood samples from 201 relatives to establish parent/child and sibling relationships. With the exception of 19 victims identified by non-genetic evidence, 183 victims were successfully identified by DNA typing with relatively high values of paternity index by the direct or indirect comparison of relatives. The 202 victims were from 37 different families, ranging in size from 2 to 13 members and 74 individuals known to be unrelated to any other victim. The DNA from living relatives was used to identify one member of a family group, from which other victims of the family could be identified. ABO blood group information was further used to confirm genetic relatedness within families. A comparison of the DNA profiling results to the ABO blood group of the victims showed no discrepancies with the exception of two mutations in the FGA locus. In cases of severely damaged victims from a plane crash, DNA analysis proved to be the best choice to identify victims.

  16. EEG source analysis using space mapping techniques

    NASA Astrophysics Data System (ADS)

    Crevecoeur, G.; Hallez, H.; van Hese, P.; D'Asseler, Y.; Dupre, L.; van de Walle, R.

    2008-06-01

    The electroencephalogram (EEG) measures potential differences, generated by electrical activity in brain tissue, between scalp electrodes. The EEG potentials can be calculated by the quasi-static Poisson equation in a certain head model. It is well known that the electrical dipole (source) which best fits the measured EEG potentials is obtained by an inverse problem. The dipole parameters are obtained by finding the global minimum of the relative residual energy (RRE). For the first time, the space mapping technique (SM technique) is used for minimizing the RRE. The SM technique aims at aligning two different simulation models: a fine model, accurate but CPU-time expensive, and a coarse model, computationally fast but less accurate than the fine one. The coarse model is a semi-analytical model, the so-called three-shell concentric sphere model. The fine model numerically solves the Poisson equation in a realistic head model. If we use the aggressive space mapping (ASM) algorithm, the errors on the dipole location are too large. The hybrid aggressive space mapping (HASM) on the other hand has better convergence properties, yielding a reduction in dipole location errors. The computational effort of HASM is greater than ASM but smaller than using direct optimization techniques.

  17. Recent trends in particle size analysis techniques

    NASA Technical Reports Server (NTRS)

    Kang, S. H.

    1984-01-01

    Recent advances and developments in the particle-sizing technologies are briefly reviewed in accordance with three operating principles including particle size and shape descriptions. Significant trends of the particle size analysing equipment recently developed show that compact electronic circuitry and rapid data processing systems were mainly adopted in the instrument design. Some newly developed techniques characterizing the particulate system were also introduced.

  18. Classification Techniques for Multivariate Data Analysis.

    DTIC Science & Technology

    1980-03-28

    analysis among biologists, botanists, and ecologists, while some social scientists may refer "typology". Other frequently encountered terms are pattern...the determinantal equation: lB -XW 0 (42) 49 The solutions X. are the eigenvalues of the matrix W-1 B 1 as in discriminant analysis. There are t non...Statistical Package for Social Sciences (SPSS) (14) subprogram FACTOR was used for the principal components analysis. It is designed both for the factor

  19. 48 CFR 15.404-1 - Proposal analysis techniques.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... are: I Price Analysis, II Quantitative Techniques for Contract Pricing, III Cost Analysis, IV Advanced... estimates. (vi) Comparison of proposed prices with prices obtained through market research for the same...

  20. 48 CFR 15.404-1 - Proposal analysis techniques.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... are: I Price Analysis, II Quantitative Techniques for Contract Pricing, III Cost Analysis, IV Advanced... estimates. (vi) Comparison of proposed prices with prices obtained through market research for the same...

  1. Three Techniques for Task Analysis: Examples from the Nuclear Utilities.

    ERIC Educational Resources Information Center

    Carlisle, Kenneth E.

    1984-01-01

    Discusses three task analysis techniques utilized at the Palo Verde Nuclear Generating Station to review training programs: analysis of (1) job positions, (2) procedures, and (3) instructional presentations. All of these include task breakdown, relationship determination, and task restructuring. (MBR)

  2. A Dimensionality Reduction Technique for Efficient Time Series Similarity Analysis

    PubMed Central

    Wang, Qiang; Megalooikonomou, Vasileios

    2008-01-01

    We propose a dimensionality reduction technique for time series analysis that significantly improves the efficiency and accuracy of similarity searches. In contrast to piecewise constant approximation (PCA) techniques that approximate each time series with constant value segments, the proposed method--Piecewise Vector Quantized Approximation--uses the closest (based on a distance measure) codeword from a codebook of key-sequences to represent each segment. The new representation is symbolic and it allows for the application of text-based retrieval techniques into time series similarity analysis. Experiments on real and simulated datasets show that the proposed technique generally outperforms PCA techniques in clustering and similarity searches. PMID:18496587

  3. Multi-Variable Analysis and Design Techniques.

    DTIC Science & Technology

    1981-09-01

    by A.G.J.MacFarlane 2 MULTIVARIABLE DESIGN TECHNIQUES BASED ON SINGULAR VALUE GENERALIZATIONS OF CLASSICAL CONTROL by J.C. Doyle 3 LIMITATIONS ON...prototypes to complex mathematical representations. All of these assemblages of information or information generators can loosely be termed "models...non linearities (e.g., control saturation) I neglect of high frequency dynamics. T hese approximations are well understood and in general their impact

  4. Objective Analysis and Prediction Techniques - 1985

    DTIC Science & Technology

    1985-11-30

    Automatic Kesocyclone Detection 162 3. Kesocyclone Discriminators 163 7 :. . . . .. . . -,, . . . . . ..... - . . . . . ... ,, . ’ TABLE OF CONTENTS...1975: High order accurate difference solutions of fluid- mechanics problems by a compact differencing technique. J. Comut. Physics, 1j, 383-390. 22...160 ft . f ft f ft f ft t f ft ft ft** fftf ftt ~~ :,.--:.*’ 8 2t 12-. . .. .f -- t. S ~ ~ ~ ~ - 7’ - -10 - - - . .. - - 12 16 00 (;M a’ 4 /v r ai i

  5. Bayesian Analysis of the Pattern Informatics Technique

    NASA Astrophysics Data System (ADS)

    Cho, N.; Tiampo, K.; Klein, W.; Rundle, J.

    2007-12-01

    The pattern informatics (PI) [Rundle et al., 2000; Tiampo et al., 2002; Holliday et al., 2005] is a technique that uses phase dynamics in order to quantify temporal variations in seismicity patterns. This technique has shown interesting results for forecasting earthquakes with magnitude greater than or equal to 5 in southern California from 2000 to 2010 [Rundle et al., 2002]. In this work, a Bayesian approach is used to obtain a modified updated version of the PI called Bayesian pattern informatics (BPI). This alternative method uses the PI result as a prior probability and models such as ETAS [Ogata, 1988, 2004; Helmstetter and Sornette, 2002] or BASS [Turcotte et al., 2007] in order to obtain the likelihood. Its result is similar to the one obtained by the PI: the determination of regions, known as hotspots, that are most susceptible to the occurrence of events with M=5 and larger during the forecast period. As an initial test, retrospective forecasts for the southern California region from 1990 to 2000 were made with both the BPI and the PI techniques, and the results are discussed in this work.

  6. [Food contamination by PCBs/dioxins in Belgium: analysis of an accident with improbable health consequences].

    PubMed

    Bernard, A

    2000-01-01

    In 1999, a food crisis broke out in Belgium as a result of the accidental contamination of animal feed by PCBs (polychlorobiphenyls) and dioxins (mainly furans). The analysis of the database from the PCB food monitoring program implemented after the discovery of incident confirms that the contamination has been very limited, both in time (peak at the end of January) and in the food chain (affecting less than 0.5% of the farms in the whole country). The extreme scenario of a doubling of the PCB and dioxin body burden as envisaged in "Nature" (401: 231-232, 1999) could have been conceivable only in the case of farmers who would have consumed their own products. But even in such an extreme case, this would mean going back to the levels of PCB and dioxin body burden of subjects living in the 1980s or of those regularly eating contaminated seafood.

  7. A probabilistic analysis of a catastrophic transuranic waste hoist accident at the WIPP

    SciTech Connect

    Greenfield, M.A. |; Sargent, T.J. |

    1993-06-01

    This report builds upon the extensive and careful analyses made by the DOE of the probability of failure of the waste hoist, and more particularly on the probability of failure of a major component, the hydraulic brake system. The extensive fault tree analysis prepared by the DOE was the starting point of the present report. A key element of this work is the use of probability distributions rather than so-called point estimates to describe the probability of failure of an element. One of the authors (MAG) developed the expressions for the probability of failure of the brake system. The second author (TJS) executed the calculations of the final expressions for failure probabilities. The authors hope that this work will be of use to the DOE in its evaluation of the safety of the waste hoist, a key element at the WIPP.

  8. Factors Associated with Fatal Occupational Accidents among Mexican Workers: A National Analysis

    PubMed Central

    Gonzalez-Delgado, Mery; Gómez-Dantés, Héctor; Fernández-Niño, Julián Alfredo; Robles, Eduardo; Borja, Víctor H.; Aguilar, Miriam

    2015-01-01

    Objective To identify the factors associated with fatal occupational injuries in Mexico in 2012 among workers affiliated with the Mexican Social Security Institute. Methods Analysis of secondary data using information from the National Occupational Risk Information System, with the consequence of the occupational injury (fatal versus non-fatal) as the response variable. The analysis included 406,222 non-fatal and 1,140 fatal injuries from 2012. The factors associated with the lethality of the injury were identified using a logistic regression model with the Firth approach. Results Being male (OR=5.86; CI95%: 4.22-8.14), age (OR=1.04; CI95%: 1.03-1.06), employed in the position for 1 to 10 years (versus less than 1 year) (OR=1.37; CI95%: 1.15-1.63), working as a facilities or machine operator or assembler (OR: 3.28; CI95%: 2.12- 5.07) and being a worker without qualifications (OR=1.96; CI95%: 1.18-3.24) (versus an office worker) were associated with fatality in the event of an injury. Additionally, companies classified as maximum risk (OR=1.90; CI 95%: 1.38-2.62), workplace conditions (OR=7.15; CI95%: 3.63-14.10) and factors related to the work environment (OR=9.18; CI95%:4.36-19.33) were identified as risk factors for fatality in the event of an occupational injury. Conclusions Fatality in the event of an occupational injury is associated with factors related to sociodemographics (age, sex and occupation), the work environment and workplace conditions. Worker protection policies should be created for groups with a higher risk of fatal occupational injuries in Mexico. PMID:25790063

  9. Soil Analysis using the semi-parametric NAA technique

    SciTech Connect

    Zamboni, C. B.; Silveira, M. A. G.; Medina, N. H.

    2007-10-26

    The semi-parametric Neutron Activation Analysis technique, using Au as a flux monitor, was applied to measure element concentrations of Br, Ca, Cl, K, Mn and Na for soil characterization. The results were compared with those using the Instrumental Neutron Activation Analysis technique and they found to be compatible. The viability, advantages, and limitations of using these two analytic methodologies are discussed.

  10. Assembly, checkout, and operation optimization analysis technique for complex systems

    NASA Technical Reports Server (NTRS)

    1968-01-01

    Computerized simulation model of a launch vehicle/ground support equipment system optimizes assembly, checkout, and operation of the system. The model is used to determine performance parameters in three phases or modes - /1/ systems optimization techniques, /2/ operation analysis methodology, and /3/ systems effectiveness analysis technique.

  11. 77 FR 40552 - Federal Acquisition Regulation; Price Analysis Techniques

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-07-10

    ...)(1), which sets forth the requirements of adequate price competition. However, only FAR 15.403-1(c)(1... Federal Acquisition Regulation; Price Analysis Techniques AGENCY: Department of Defense (DoD), General... clarify the use of a price analysis technique in order to establish a fair and reasonable price....

  12. Accident prevention in radiotherapy

    PubMed Central

    Holmberg, O

    2007-01-01

    In order to prevent accidents in radiotherapy, it is important to learn from accidents that have occurred previously. Lessons learned from a number of accidents are summarised and underlying patterns are looked for in this paper. Accidents can be prevented by applying several safety layers of preventive actions. Categories of these preventive actions are discussed together with specific actions belonging to each category of safety layer. PMID:21614274

  13. GAS CURTAIN EXPERIMENTAL TECHNIQUE AND ANALYSIS METHODOLOGIES

    SciTech Connect

    J. R. KAMM; ET AL

    2001-01-01

    The qualitative and quantitative relationship of numerical simulation to the physical phenomena being modeled is of paramount importance in computational physics. If the phenomena are dominated by irregular (i. e., nonsmooth or disordered) behavior, then pointwise comparisons cannot be made and statistical measures are required. The problem we consider is the gas curtain Richtmyer-Meshkov (RM) instability experiments of Rightley et al. (13), which exhibit complicated, disordered motion. We examine four spectral analysis methods for quantifying the experimental data and computed results: Fourier analysis, structure functions, fractal analysis, and continuous wavelet transforms. We investigate the applicability of these methods for quantifying the details of fluid mixing.

  14. GAS CURTAIN EXPERIMENTAL TECHNIQUE AND ANALYSIS METHODOLOGIES.

    SciTech Connect

    Kamm, J. R.; Rider, William; Rightley, P. M.; Prestridge, K. P.; Benjamin, R. F.; Vorobieff, P. V.

    2001-01-01

    The qualitative and quantitative relationship of numerical simulation to the physical phenomena being modeled is of paramount importance in computational physics. If the phenomena are dominated by irregular (i.e., nonsmooth or disordered) behavior, then pointwise comparisons cannot be made and statistical measures are required. The problem we consider is the gas curtain Richtmyer-Meshkov (RM) instability experiments of Rightley et al. [13], which exhibit complicated, disordered motion. We examine four spectral analysis methods for quantifying the experimental data and computed results: Fourier analysis, structure functions, fractal analysis, and continuous wavelet transforms. We investigate the applicability of these methods for quantifying the details of fluid mixing.

  15. Statistical Analysis Techniques for Small Sample Sizes

    NASA Technical Reports Server (NTRS)

    Navard, S. E.

    1984-01-01

    The small sample sizes problem which is encountered when dealing with analysis of space-flight data is examined. Because of such a amount of data available, careful analyses are essential to extract the maximum amount of information with acceptable accuracy. Statistical analysis of small samples is described. The background material necessary for understanding statistical hypothesis testing is outlined and the various tests which can be done on small samples are explained. Emphasis is on the underlying assumptions of each test and on considerations needed to choose the most appropriate test for a given type of analysis.

  16. Overview on techniques in cluster analysis.

    PubMed

    Frades, Itziar; Matthiesen, Rune

    2010-01-01

    Clustering is the unsupervised, semisupervised, and supervised classification of patterns into groups. The clustering problem has been addressed in many contexts and disciplines. Cluster analysis encompasses different methods and algorithms for grouping objects of similar kinds into respective categories. In this chapter, we describe a number of methods and algorithms for cluster analysis in a stepwise framework. The steps of a typical clustering analysis process include sequentially pattern representation, the choice of the similarity measure, the choice of the clustering algorithm, the assessment of the output, and the representation of the clusters.

  17. In-Containment Thermal-hydraulic and Aerosol Behaviour during Severe Accidents: Analysis of the PHEBUS-FPT2 Experiment

    SciTech Connect

    Herranz, Luis E.; Fontanet, Joan; Vela-Garcia, Monica

    2006-07-01

    Ongoing work in the area of development and validation of severe accident computer codes, is and will be highly valuable when dealing with safety analysis of some designs of Generation III, III+ and, even, Generation IV. In the experiment PHEBUS-FPT2 a realistic source of nuclear aerosols was generated in the core and transported through a mock-up of the primary circuit up to a containment vessel where weak condensing conditions were imposed in a largely unsaturated atmosphere. By using CONTAIN 2.0, MELCOR 1.8.5 and ASTEC 1.1, the experimental scenario has been modeled. All the codes share similar characteristics and approached the experimental scenario in a quite simple way. The same assumptions have been made and the only major difference has been the three-cell nodalization of the vessel in the case of ASTEC 1.1 (a single cell was used in CONTAIN and MELCOR). No major code-to-code differences have stemmed from the different meshing schemes used in the vessel modeling. However, some minor differences have been observed between ASTEC and the American codes in variables like gas temperature or settled mass. The agreement of code estimates with available data can be said to be acceptable. Slight discrepancies found in steam partial pressure seem to indicate that codes over-estimated steam condensation rate during the first 2000 s. Potential uncertainties in surface temperature could well explain this. Overall evolution of airborne aerosols has been satisfactorily predicted. However, all the codes noticeably overestimate sedimentation. Sensitivity studies carried out on particles size, shape and density have indicated that uncertainties on those variables cannot justify the magnitude of the deviation found. (authors)

  18. Emulation and Sobol' sensitivity analysis of an atmospheric dispersion model applied to the Fukushima nuclear accident

    NASA Astrophysics Data System (ADS)

    Girard, Sylvain; Mallet, Vivien; Korsakissok, Irène; Mathieu, Anne

    2016-04-01

    Simulations of the atmospheric dispersion of radionuclides involve large uncertainties originating from the limited knowledge of meteorological input data, composition, amount and timing of emissions, and some model parameters. The estimation of these uncertainties is an essential complement to modeling for decision making in case of an accidental release. We have studied the relative influence of a set of uncertain inputs on several outputs from the Eulerian model Polyphemus/Polair3D on the Fukushima case. We chose to use the variance-based sensitivity analysis method of Sobol'. This method requires a large number of model evaluations which was not achievable directly due to the high computational cost of Polyphemus/Polair3D. To circumvent this issue, we built a mathematical approximation of the model using Gaussian process emulation. We observed that aggregated outputs are mainly driven by the amount of emitted radionuclides, while local outputs are mostly sensitive to wind perturbations. The release height is notably influential, but only in the vicinity of the source. Finally, averaging either spatially or temporally tends to cancel out interactions between uncertain inputs.

  19. Effect of alternative aging and accident simulations on polymer properties

    SciTech Connect

    Bustard, L.D.; Chenion, J.; Carlin, F.; Alba, C.; Gaussens, G.; LeMeur, M.

    1984-01-01

    The response of eighteen US and French polymer materials to variations in aging and accident simulation techniques has been determined by this experimental program. This information will provide a partial data base by which to judge appropriate simulation practices. The overall research goal was to determine whether some aging and accident simulation techniques are better suited for qualification activities than other alternative simulation techniques.

  20. PF-4 simulated fire accident analysis: Filter-spray cool-down system reevaluation implications

    SciTech Connect

    White, B.W.; Gregory, W.S.

    1990-10-01

    The Los Alamos National Laboratory PF-4 facility was designed with spray cool down systems within the building's ventilation systems. The Engineering and Safety Analysis Group was asked, in cooperation with ENG-8 and MST-8, to evaluate whether the spray cool-down system still need to be classified as safety class'' systems. The study was performed using the FIRAC computer code. Given the fire source terms (hypothetical fire energy or time-temperature history), FIRAC can predict the pertinent transient flow parameters (pressures, flows, and temperatures) throughout a previously defined and selected fire zone. A computer model for the study that had all of the main ventilation systems in the south half of the PF-4 facility was used. Because the most hazardous room is located in the 400 Section, all ventilation systems but the 400 Section's one were simplified. The impetus for simplification was to keep the computer model tractable, and this was possible with the following assumptions: the fire cannot spread from one room to another, all corridor connecting doors are closed and will not fail under the pressures generated by the fire, and the principal pathway for potential release is the ventilation system. All of the blowers continue to operate, and all fire retardant systems fail to operate during the fire. The ASTM time-temperature curve was the source for the burn-room temperature, and smoke injection was used as input as well. Five different computer runs were made using different combinations of source terms and heat transfer. A connection from the burn room to the glovebox ventilation system was created by burning the glovebox plastic shielding; it was modeled by a branch having an initial flow 75 ft{sup 3}/min. 7 refs., 35 refs., 15 tabs.

  1. 48 CFR 215.404-1 - Proposal analysis techniques.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 48 Federal Acquisition Regulations System 3 2014-10-01 2014-10-01 false Proposal analysis... Contract Pricing 215.404-1 Proposal analysis techniques. (1) Follow the procedures at PGI 215.404-1 for proposal analysis. (2) For spare parts or support equipment, perform an analysis of— (i) Those line...

  2. Does periodic vehicle inspection prevent accidents?

    PubMed

    White, W T

    1986-02-01

    The hypothesis that periodic motor vehicle inspection (PMVI) has no safety effect was tested using accident involvement rates analysed by "vehicle age" and "time since the most recent inspection." The alternative of interest was that the probability of accident is lowest (ceteris paribus) immediately after an inspection, and subsequently increases over time. Two types of adjustment for exposure variations by time since last inspection were made, yielding two kinds of accident involvement rate. The first accident rate was the proportion of accident-involved vehicles having "preventable" defects which could possibly have helped to cause the accident. The second accident rate was the number of accident-involved vehicles divided by the number of inspected vehicles, and amounted to an adjustment for premature re-inspection. The observed probability of accident involvement (as measured by either rate) was found to increase with time since last inspection. This result supports the alternative hypothesis that a mandatory safety inspection has an immediate safety benefit which decreases over time. In neither analysis was there an interaction between vehicle age group and "week since inspection."

  3. Bayes classifiers for imbalanced traffic accidents datasets.

    PubMed

    Mujalli, Randa Oqab; López, Griselda; Garach, Laura

    2016-03-01

    Traffic accidents data sets are usually imbalanced, where the number of instances classified under the killed or severe injuries class (minority) is much lower than those classified under the slight injuries class (majority). This, however, supposes a challenging problem for classification algorithms and may cause obtaining a model that well cover the slight injuries instances whereas the killed or severe injuries instances are misclassified frequently. Based on traffic accidents data collected on urban and suburban roads in Jordan for three years (2009-2011); three different data balancing techniques were used: under-sampling which removes some instances of the majority class, oversampling which creates new instances of the minority class and a mix technique that combines both. In addition, different Bayes classifiers were compared for the different imbalanced and balanced data sets: Averaged One-Dependence Estimators, Weightily Average One-Dependence Estimators, and Bayesian networks in order to identify factors that affect the severity of an accident. The results indicated that using the balanced data sets, especially those created using oversampling techniques, with Bayesian networks improved classifying a traffic accident according to its severity and reduced the misclassification of killed and severe injuries instances. On the other hand, the following variables were found to contribute to the occurrence of a killed causality or a severe injury in a traffic accident: number of vehicles involved, accident pattern, number of directions, accident type, lighting, surface condition, and speed limit. This work, to the knowledge of the authors, is the first that aims at analyzing historical data records for traffic accidents occurring in Jordan and the first to apply balancing techniques to analyze injury severity of traffic accidents.

  4. Uncertainty analysis technique for OMEGA Dante measurementsa)

    NASA Astrophysics Data System (ADS)

    May, M. J.; Widmann, K.; Sorce, C.; Park, H.-S.; Schneider, M.

    2010-10-01

    The Dante is an 18 channel x-ray filtered diode array which records the spectrally and temporally resolved radiation flux from various targets (e.g., hohlraums, etc.) at x-ray energies between 50 eV and 10 keV. It is a main diagnostic installed on the OMEGA laser facility at the Laboratory for Laser Energetics, University of Rochester. The absolute flux is determined from the photometric calibration of the x-ray diodes, filters and mirrors, and an unfold algorithm. Understanding the errors on this absolute measurement is critical for understanding hohlraum energetic physics. We present a new method for quantifying the uncertainties on the determined flux using a Monte Carlo parameter variation technique. This technique combines the uncertainties in both the unfold algorithm and the error from the absolute calibration of each channel into a one sigma Gaussian error function. One thousand test voltage sets are created using these error functions and processed by the unfold algorithm to produce individual spectra and fluxes. Statistical methods are applied to the resultant set of fluxes to estimate error bars on the measurements.

  5. Uncertainty analysis technique for OMEGA Dante measurements.

    PubMed

    May, M J; Widmann, K; Sorce, C; Park, H-S; Schneider, M

    2010-10-01

    The Dante is an 18 channel x-ray filtered diode array which records the spectrally and temporally resolved radiation flux from various targets (e.g., hohlraums, etc.) at x-ray energies between 50 eV and 10 keV. It is a main diagnostic installed on the OMEGA laser facility at the Laboratory for Laser Energetics, University of Rochester. The absolute flux is determined from the photometric calibration of the x-ray diodes, filters and mirrors, and an unfold algorithm. Understanding the errors on this absolute measurement is critical for understanding hohlraum energetic physics. We present a new method for quantifying the uncertainties on the determined flux using a Monte Carlo parameter variation technique. This technique combines the uncertainties in both the unfold algorithm and the error from the absolute calibration of each channel into a one sigma Gaussian error function. One thousand test voltage sets are created using these error functions and processed by the unfold algorithm to produce individual spectra and fluxes. Statistical methods are applied to the resultant set of fluxes to estimate error bars on the measurements.

  6. Injection Locking Techniques for Spectrum Analysis

    NASA Astrophysics Data System (ADS)

    Gathma, Timothy D.; Buckwalter, James F.

    2011-04-01

    Wideband spectrum analysis supports future communication systems that reconfigure and adapt to the capacity of the spectral environment. While test equipment manufacturers offer wideband spectrum analyzers with excellent sensitivity and resolution, these spectrum analyzers typically cannot offer acceptable size, weight, and power (SWAP). CMOS integrated circuits offer the potential to fully integrate spectrum analysis capability with analog front-end circuitry and digital signal processing on a single chip. Unfortunately, CMOS lacks high-Q passives and wideband resonator tunability that is necessary for heterodyne implementations of spectrum analyzers. As an alternative to the heterodyne receiver architectures, two nonlinear methods for performing wideband, low-power spectrum analysis are presented. The first method involves injecting the spectrum of interest into an array of injection-locked oscillators. The second method employs the closed loop dynamics of both injection locking and phase locking to independently estimate the injected frequency and power.

  7. Injection Locking Techniques for Spectrum Analysis

    SciTech Connect

    Gathma, Timothy D.; Buckwalter, James F.

    2011-04-19

    Wideband spectrum analysis supports future communication systems that reconfigure and adapt to the capacity of the spectral environment. While test equipment manufacturers offer wideband spectrum analyzers with excellent sensitivity and resolution, these spectrum analyzers typically cannot offer acceptable size, weight, and power (SWAP). CMOS integrated circuits offer the potential to fully integrate spectrum analysis capability with analog front-end circuitry and digital signal processing on a single chip. Unfortunately, CMOS lacks high-Q passives and wideband resonator tunability that is necessary for heterodyne implementations of spectrum analyzers. As an alternative to the heterodyne receiver architectures, two nonlinear methods for performing wideband, low-power spectrum analysis are presented. The first method involves injecting the spectrum of interest into an array of injection-locked oscillators. The second method employs the closed loop dynamics of both injection locking and phase locking to independently estimate the injected frequency and power.

  8. Automated fluid analysis apparatus and techniques

    DOEpatents

    Szecsody, James E.

    2004-03-16

    An automated device that couples a pair of differently sized sample loops with a syringe pump and a source of degassed water. A fluid sample is mounted at an inlet port and delivered to the sample loops. A selected sample from the sample loops is diluted in the syringe pump with the degassed water and fed to a flow through detector for analysis. The sample inlet is also directly connected to the syringe pump to selectively perform analysis without dilution. The device is airtight and used to detect oxygen-sensitive species, such as dithionite in groundwater following a remedial injection to treat soil contamination.

  9. Comparison of Hydrogen Sulfide Analysis Techniques

    ERIC Educational Resources Information Center

    Bethea, Robert M.

    1973-01-01

    A summary and critique of common methods of hydrogen sulfide analysis is presented. Procedures described are: reflectance from silver plates and lead acetate-coated tiles, lead acetate and mercuric chloride paper tapes, sodium nitroprusside and methylene blue wet chemical methods, infrared spectrophotometry, and gas chromatography. (BL)

  10. Permethylation Linkage Analysis Techniques for Residual Carbohydrates

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Permethylation analysis is the classic approach to establishing the position of glycosidic linkages between sugar residues. Typically, the carbohydrate is derivatized to form acid-stable methyl ethers, hydrolyzed, peracetylated, and analyzed by gas chromatography-mass spectrometry (GC-MS). The pos...

  11. HELCATS - Heliospheric Cataloguing, Analysis and Techniques Service

    NASA Astrophysics Data System (ADS)

    Harrison, Richard; Davies, Jackie; Perry, Chris; Moestl, Christian; Rouillard, Alexis; Bothmer, Volker; Rodriguez, Luciano; Eastwood, Jonathan; Kilpua, Emilia; Gallagher, Peter

    2016-04-01

    Understanding the evolution of the solar wind is fundamental to advancing our knowledge of energy and mass transport in the solar system, rendering it crucial to space weather and its prediction. The advent of truly wide-angle heliospheric imaging has revolutionised the study of both transient (CMEs) and background (SIRs/CIRs) solar wind plasma structures, by enabling their direct and continuous observation out to 1 AU and beyond. The EU-funded FP7 HELCATS project combines European expertise in heliospheric imaging, built up in particular through lead involvement in NASA's STEREO mission, with expertise in solar and coronal imaging as well as in-situ and radio measurements of solar wind phenomena, in a programme of work that will enable a much wider exploitation and understanding of heliospheric imaging observations. With HELCATS, we are (1.) cataloguing transient and background solar wind structures imaged in the heliosphere by STEREO/HI, since launch in late October 2006 to date, including estimates of their kinematic properties based on a variety of established techniques and more speculative, approaches; (2.) evaluating these kinematic properties, and thereby the validity of these techniques, through comparison with solar source observations and in-situ measurements made at multiple points throughout the heliosphere; (3.) appraising the potential for initialising advanced numerical models based on these kinematic properties; (4.) assessing the complementarity of radio observations (in particular of Type II radio bursts and interplanetary scintillation) in combination with heliospheric imagery. We will, in this presentation, provide an overview of progress from the first 18 months of the HELCATS project.

  12. Analysis of 129I in the soils of Fukushima Prefecture: preliminary reconstruction of 131I deposition related to the accident at Fukushima Daiichi Nuclear Power Plant (FDNPP).

    PubMed

    Muramatsu, Yasuyuki; Matsuzaki, Hiroyuki; Toyama, Chiaki; Ohno, Takeshi

    2015-01-01

    Iodine-131 is one of the most critical radionuclides to be monitored after release from reactor accidents due to the tendency for this nuclide to accumulate in the human thyroid gland. However, there are not enough data related to the reactor accident in Fukushima, Japan to provide regional information on the deposition of this short-lived nuclide (half-life = 8.02 d). In this study we have focused on the long-lived iodine isotope, (129)I (half-life of 1.57 × 10(7) y), and analyzed it by accelerator mass spectrometry (AMS) for surface soil samples collected at various locations in Fukushima Prefecture. In order to obtain information on the (131)I/(129)I ratio released from the accident, we have determined (129)I concentrations in 82 soil samples in which (131)I concentrations were previously determined. There was a strong correlation (R(2) = 0.84) between the two nuclides, suggesting that the (131)I levels in soil samples following the accident can be estimated through the analysis of (129)I. We have also examined the possible influence from (129m)Te on (129)I, and found no significant effect. In order to construct a deposition map of (131)I, we determined the (129)I concentrations (Bq/kg) in 388 soil samples collected from different locations in Fukushima Prefecture and the deposition densities (Bq/m(2)) of (131)I were reconstructed from the results.

  13. Vertebral fractures in motor vehicle accidents - a medical and technical analysis of 33,015 injured front-seat occupants.

    PubMed

    Müller, Christian W; Otte, Dietmar; Decker, Sebastian; Stübig, Timo; Panzica, Martin; Krettek, Christian; Brand, Stephan

    2014-05-01

    Spinal injuries pose a considerable risk to life and quality of life. In spite of improvements in active and passive safety of motor vehicles, car accidents are regarded as a major cause for vertebral fractures. The purpose of this study was to evaluate the current incidence of vertebral fractures among front-seat occupants in motor vehicle accidents, and to identify specific risk factors for sustaining vertebral fractures in motor vehicle accidents. Data from an accident research unit were accessed to collect collision details, preclinical data, and clinical data. We included all data on front-seat occupants. Hospital records were retrieved, and radiological images were evaluated. We analysed 33,015 front-seat occupants involved in motor vehicle accidents over a 24-year period. We identified 126 subjects (0.38%) with cervical spine fractures, 78 (0.24%) with thoracic fractures, and 99 (0.30%) with lumbar fractures. The mean relative collision speeds were 48, 39, and 40 kph in subjects with cervical, thoracic, and lumbar spine fractures, respectively, while it was 17.3 kph in the whole cohort. Contrary to the overall cohort, these patients typically sustained multiple hits rather than simple front collisions. Occupants with vertebral fractures frequently showed numerous concomitant injuries; for example, additional vertebral fractures. The incidence of vertebral fractures corresponded with collision speed. Safety belts were highly effective in the prevention of vertebral fractures. Apart from high speed, complex injury mechanisms as multiple collisions or rollovers were associated with vertebral fractures. Additional preventive measures should focus on these collision mechanisms.

  14. A comparison of wavelet analysis techniques in digital holograms

    NASA Astrophysics Data System (ADS)

    Molony, Karen M.; Maycock, Jonathan; McDonald, John B.; Hennelly, Bryan M.; Naughton, Thomas J.

    2008-04-01

    This study explores the effectiveness of wavelet analysis techniques on digital holograms of real-world 3D objects. Stationary and discrete wavelet transform techniques have been applied for noise reduction and compared. Noise is a common problem in image analysis and successful reduction of noise without degradation of content is difficult to achieve. These wavelet transform denoising techniques are contrasted with traditional noise reduction techniques; mean filtering, median filtering, Fourier filtering. The different approaches are compared in terms of speckle reduction, edge preservation and resolution preservation.

  15. Autoregressive and bispectral analysis techniques: EEG applications.

    PubMed

    Ning, T; Bronzino, J D

    1990-01-01

    Some basic properties of autoregressive (AR) modeling and bispectral analysis are reviewed, and examples of their application in electroencephalography (EEG) research are provided. A second-order AR model was used to score cortical EEGs in order. In tests performed on five adult rats to distinguish between different vigilance states such a quiet-waking (QW), rapid-eye-movement (REM), and slow-wave sleep (SWS), SWS activity was correctly identified over 96% of the time, and a 95% agreement rate was achieved in recognizing the REM sleep stage. In a bispectral analysis of the rat EEG, third-order cumulant (TOC) sequences of 32 epochs belonging to the same vigilance state were estimated and then averaged. Preliminary results have shown that bispectra of hippocampal EEGs during REM Sleep exhibit significant quadratic phase couplings between frequencies in the 6-8-Hz range, associated with the theta rhythm.

  16. Whitewater River Accident Analysis.

    ERIC Educational Resources Information Center

    Watters, Ron

    Critical decision making on a whitewater trip goes beyond simply having knowledge of safety practices. Rather, prudent decisions are arrived at through a complex interplay of diverse factors. The question is: how can outdoor educators prepare themselves and their staff to make the "right" decision when faced with a potentially dangerous…

  17. Bibliography for nuclear criticality accident experience, alarm systems, and emergency management

    SciTech Connect

    Putman, V.L.

    1995-09-01

    The characteristics, detection, and emergency management of nuclear criticality accidents outside reactors has been an important component of criticality safety for as long as the need for this specialized safety discipline has been recognized. The general interest and importance of such topics receives special emphasis because of the potentially lethal, albeit highly localized, effects of criticality accidents and because of heightened public and regulatory concerns for any undesirable event in nuclear and radiological fields. This bibliography lists references which are potentially applicable to or interesting for criticality alarm, detection, and warning systems; criticality accident emergency management; and their associated programs. The lists are annotated to assist bibliography users in identifying applicable: industry and regulatory guidance and requirements, with historical development information and comments; criticality accident characteristics, consequences, experiences, and responses; hazard-, risk-, or safety-analysis criteria; CAS design and qualification criteria; CAS calibration, maintenance, repair, and testing criteria; experiences of CAS designers and maintainers; criticality accident emergency management (planning, preparedness, response, and recovery) requirements and guidance; criticality accident emergency management experience, plans, and techniques; methods and tools for analysis; and additional bibliographies.

  18. A technique for human error analysis (ATHEANA)

    SciTech Connect

    Cooper, S.E.; Ramey-Smith, A.M.; Wreathall, J.; Parry, G.W.

    1996-05-01

    Probabilistic risk assessment (PRA) has become an important tool in the nuclear power industry, both for the Nuclear Regulatory Commission (NRC) and the operating utilities. Human reliability analysis (HRA) is a critical element of PRA; however, limitations in the analysis of human actions in PRAs have long been recognized as a constraint when using PRA. A multidisciplinary HRA framework has been developed with the objective of providing a structured approach for analyzing operating experience and understanding nuclear plant safety, human error, and the underlying factors that affect them. The concepts of the framework have matured into a rudimentary working HRA method. A trial application of the method has demonstrated that it is possible to identify potentially significant human failure events from actual operating experience which are not generally included in current PRAs, as well as to identify associated performance shaping factors and plant conditions that have an observable impact on the frequency of core damage. A general process was developed, albeit in preliminary form, that addresses the iterative steps of defining human failure events and estimating their probabilities using search schemes. Additionally, a knowledge- base was developed which describes the links between performance shaping factors and resulting unsafe actions.

  19. Speckle-adaptive VISAR fringe analysis technique

    NASA Astrophysics Data System (ADS)

    Erskine, David

    2017-01-01

    A line-VISAR (velocity interferometer) is an important diagnostic in shock physics, simultaneously measuring many fringe histories of adjacent portions of a target splayed along a line on a target, with fringes recorded vs time and space by a streak camera. Due to laser speckle the reflected intensity may be uneven spatially, and due to irregularities in the streak camera electron optics the phase along the slit may be slightly nonlinear. Conventional fringe analysis algorithms which do not properly model these variations can suffer from inferred velocity errors. A speckle-adaptive algorithm has been developed which senses the interferometer and illumination parameters for each individual row (spatial position Y) of the 2d interferogram, so that the interferogram can be compensated for Y-dependent nonfringing intensity, fringe visibility, and nonlinear phase distribution. In numerical simulations and on actual data we have found this individual row-by-row modeling improves the accuracy of the result, compared to a conventional column-by-column analysis approach.

  20. Improvement of Rocket Engine Plume Analysis Techniques

    NASA Technical Reports Server (NTRS)

    Smith, S. D.

    1982-01-01

    A nozzle plume flow field code was developed. The RAMP code which was chosen as the basic code is of modular construction and has the following capabilities: two phase with two phase transonic solution; a two phase, reacting gas (chemical equilibrium reaction kinetics), supersonic inviscid nozzle/plume solution; and is operational for inviscid solutions at both high and low altitudes. The following capabilities were added to the code: a direct interface with JANNAF SPF code; shock capturing finite difference numerical operator; two phase, equilibrium/frozen, boundary layer analysis; a variable oxidizer to fuel ratio transonic solution; an improved two phase transonic solution; and a two phase real gas semiempirical nozzle boundary layer expansion.

  1. Investigation of electroforming techniques, literature analysis report

    NASA Technical Reports Server (NTRS)

    Malone, G. A.

    1975-01-01

    A literature analysis is presented of reports, specifications, and documented experiences with the use of electroforming to produce copper and nickel structures for aerospace and other engineering applications. The literature period covered is from 1948 to 1974. Specific effort was made to correlate mechanical property data for the electrodeposited material with known electroforming solution compositions and operating conditions. From this survey, electrolytes are suggested for selection to electroform copper and nickel outer shells on regeneratively cooled thrust chamber liners, and other devices subject to thermal and pressure exposure, based on mechanical properties obtainable, performance under various thermal environments, and ease of process control for product reproducibility. Processes of potential value in obtaining sound bonds between electrodeposited copper and nickel and copper alloy substrates are also discussed.

  2. Near Real Time Quantitative Gas Analysis Techniques

    NASA Astrophysics Data System (ADS)

    Herget, William F.; Tromp, Marianne L.; Anderson, Charles R.

    1985-12-01

    A Fourier transform infrared (FT-IR) - based system has been developed and is undergoing evaluation for near real time multicomponent quantitative analysis of undiluted gaseous automotive exhaust emissions. The total system includes: (1) a gas conditioning system (GCS) for tracer gas injection, gas mixing, and temperature stabilization; and (2) an exhaust gas analyzer (EGA) consisting of a sample cell, an FT-IR system, and a computerized data processing system. Tests have shown that the system can monitor about 20 individual species (concentrations down to the 1-20 ppm range) with a time resolution of one second. Tests have been conducted on a chassis dynamometer system utilizing different autos, different fuels, and different driving cycles. Results were compared with those obtained using a standard constant volume sampling (CVS) system.

  3. Type A Accident Investigation Board report on the January 17, 1996, electrical accident with injury in Technical Area 21 Tritium Science and Fabrication Facility Los Alamos National Laboratory. Final report

    SciTech Connect

    1996-04-01

    An electrical accident was investigated in which a crafts person received serious injuries as a result of coming into contact with a 13.2 kilovolt (kV) electrical cable in the basement of Building 209 in Technical Area 21 (TA-21-209) in the Tritium Science and Fabrication Facility (TSFF) at Los Alamos National Laboratory (LANL). In conducting its investigation, the Accident Investigation Board used various analytical techniques, including events and causal factor analysis, barrier analysis, change analysis, fault tree analysis, materials analysis, and root cause analysis. The board inspected the accident site, reviewed events surrounding the accident, conducted extensive interviews and document reviews, and performed causation analyses to determine the factors that contributed to the accident, including any management system deficiencies. Relevant management systems and factors that could have contributed to the accident were evaluated in accordance with the guiding principles of safety management identified by the Secretary of Energy in an October 1994 letter to the Defense Nuclear Facilities Safety Board and subsequently to Congress.

  4. Energy minimization versus pseudo force technique for nonlinear structural analysis

    NASA Technical Reports Server (NTRS)

    Kamat, M. P.; Hayduk, R. J.

    1980-01-01

    The effectiveness of using minimization techniques for the solution of nonlinear structural analysis problems is discussed and demonstrated by comparison with the conventional pseudo force technique. The comparison involves nonlinear problems with a relatively few degrees of freedom. A survey of the state-of-the-art of algorithms for unconstrained minimization reveals that extension of the technique to large scale nonlinear systems is possible.

  5. Fatal traffic accidents among trailer truck drivers and accident causes as viewed by other truck drivers.

    PubMed

    Häkkänen, H; Summala, H

    2001-03-01

    Causality factors, the responsibility of the driver and driver fatigue-related factors were studied in fatal two-vehicle accidents where a trailer truck driver was involved during the period of 1991-1997 (n = 337). In addition, 251 long-haul truck drivers were surveyed in order to study their views regarding contributing factors in accidents involving trucks and the development of possible countermeasure against driver fatigue. Trailer truck drivers were principally responsible for 16% of all the accidents. Younger driver age and driving during evening hours were significant predictors of being principally responsible. In addition, the probability of being principally responsible for the accident increased by a factor of over three if the driver had a chronic illness. Prolonged driving preceding the accident, accident history or traffic offence history did not have a significant effect. Only 2% of the drivers were estimated to have fallen asleep while driving just prior to the accident, and altogether 4% of the drivers had been tired prior to the accident. Of the drivers 13% had however, been driving over 10 h preceding the accident (which has been criminally punishably in Finland since 1995 under the EC regulation) but no individual factors had a significant effect in predicting prolonged driving. The surveyed views regarding causes of truck accidents correspond well with the accident analysis. Accidents were viewed as being most often caused by other road users and driver fatigue was viewed to be no more than the fifth (out of eight) common cause of accidents. The probability of viewing fatigue as a more common cause increased significantly if the driver had experienced fatigue-related problems while driving. However, nearly half of the surveyed truck drivers expressed a negative view towards developing a technological countermeasure against driver fatigue. The negative view was not related to personal experiences of fatigue-related problems while driving.

  6. Analysis and calibration techniques for superconducting resonators.

    PubMed

    Cataldo, Giuseppe; Wollack, Edward J; Barrentine, Emily M; Brown, Ari D; Moseley, S Harvey; U-Yen, Kongpop

    2015-01-01

    A method is proposed and experimentally explored for in-situ calibration of complex transmission data for superconducting microwave resonators. This cryogenic calibration method accounts for the instrumental transmission response between the vector network analyzer reference plane and the device calibration plane. Once calibrated, the observed resonator response is analyzed in detail by two approaches. The first, a phenomenological model based on physically realizable rational functions, enables the extraction of multiple resonance frequencies and widths for coupled resonators without explicit specification of the circuit network. In the second, an ABCD-matrix representation for the distributed transmission line circuit is used to model the observed response from the characteristic impedance and propagation constant. When used in conjunction with electromagnetic simulations, the kinetic inductance fraction can be determined with this method with an accuracy of 2%. Datasets for superconducting microstrip and coplanar-waveguide resonator devices were investigated and a recovery within 1% of the observed complex transmission amplitude was achieved with both analysis approaches. The experimental configuration used in microwave characterization of the devices and self-consistent constraints for the electromagnetic constitutive relations for parameter extraction are also presented.

  7. A procedural analysis of correspondence training techniques

    PubMed Central

    Paniagua, Freddy A.

    1990-01-01

    A variety of names have been given to procedures used in correspondence training, some more descriptive than others. In this article I argue that a terminology more accurately describing actual procedures, rather than the conceptual function that those procedures are assumed to serve, would benefit the area of correspondence training. I identify two documented procedures during the reinforcement of verbalization phase and five procedures during the reinforcement of correspondence phase and suggest that those procedures can be classified, or grouped into nonoverlapping categories, by specifying the critical dimensions of those procedures belonging to a single category. I suggest that the names of such nonoverlapping categories should clearly specify the dimensions on which the classification is based in order to facilitate experimental comparison of procedures, and to be able to recognize when a new procedure (as opposed to a variant of one already in existence) is developed. Future research involving comparative analysis across and within procedures is discussed within the framework of the proposed classification. PMID:22478059

  8. 48 CFR 215.404-1 - Proposal analysis techniques.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... techniques. 215.404-1 Section 215.404-1 Federal Acquisition Regulations System DEFENSE ACQUISITION REGULATIONS SYSTEM, DEPARTMENT OF DEFENSE CONTRACTING METHODS AND CONTRACT TYPES CONTRACTING BY NEGOTIATION Contract Pricing 215.404-1 Proposal analysis techniques. (1) Follow the procedures at PGI 215.404-1...

  9. Road Traffic Accidents in Kazakhstan

    PubMed Central

    AUBAKIROVA, Alma; KOSSUMOV, Alibek; IGISSINOV, Nurbek

    2013-01-01

    Background: The article provides the analysis of death rates in road traffic accidents in Kazakhstan from 2004 to 2010 and explores the use of sanitary aviation. Methods: Data of fatalities caused by road traffic accidents were collected and analysed. Descriptive and analytical methods of epidemiology and biomedical statistics were applied. Results: Totaly 27,003 people died as a result of road traffic accidents in this period. The death rate for the total population due to road traffic accidents was 25.0±2.10/0000. The death rate for men was (38.3±3.20/0000), which was higher (P<0.05) than that for women (12.6±1.10/0000). High death rates in the entire male population were identified among men of 30–39 years old, whereas the highest rates for women were attributed to the groups of 50–59 years old and 70–79 years old. In time dynamics, death rates tended to decrease: the total population (Tdec=−2.4%), men (Tdec=−2.3%) and women (Tdec=−1.4%). When researching territorial relevance, the rates were established as low (to 18.30/0000), average (between 18.3 and 24.00/0000) and high (from 24.00/0000 and above). Thus, the regions with high rates included Akmola region (24.30/0000), Mangistau region (25.90/0000), Zhambyl region (27.30/0000), Almaty region (29.30/0000) and South Kazakhstan region (32.40/0000). Conclusion: The identified epidemiological characteristics of the population deaths rates from road traffic accidents should be used in integrated and targeted interventions to enhance prevention of injuries in accidents. PMID:23641400

  10. The Fukushima Daiichi Accident Study Information Portal

    SciTech Connect

    Shawn St. Germain; Curtis Smith; David Schwieder; Cherie Phelan

    2012-11-01

    This paper presents a description of The Fukushima Daiichi Accident Study Information Portal. The Information Portal was created by the Idaho National Laboratory as part of joint NRC and DOE project to assess the severe accident modeling capability of the MELCOR analysis code. The Fukushima Daiichi Accident Study Information Portal was created to collect, store, retrieve and validate information and data for use in reconstructing the Fukushima Daiichi accident. In addition to supporting the MELCOR simulations, the Portal will be the main DOE repository for all data, studies and reports related to the accident at the Fukushima Daiichi nuclear power station. The data is stored in a secured (password protected and encrypted) repository that is searchable and accessible to researchers at diverse locations.

  11. Candu 6 severe core damage accident consequence analysis for steam generator tube rupture scenario using MAAP4-CANDU V4.0.5A: preliminary results

    SciTech Connect

    Petoukhov, S.M.; Awadh, B.; Mathew, P.M.

    2006-07-01

    This paper describes the preliminary results of the consequence analysis for a generic AECL CANDU 6 station, when it undergoes a postulated, low probability Steam Generator multiple Tube Rupture (SGTR) severe accident with assumed unavailability of several critical plant safety systems. The Modular Accident Analysis Program for CANDU (MAAP4-CANDU) code was used for this analysis. The SGTR accident is assumed to begin with the guillotine rupture of 10 steam generator tubes in one steam generator in Primary Heat Transport System (PHTS) loop 1. For the reference case, the following systems were assumed unavailable: moderator and shield cooling, emergency core cooling, crash cool-down, and main and auxiliary feed water. Two additional cases were analyzed, one with the crash cool-down system available, and another with the crash cool-down and the auxiliary feed water systems available. The three scenarios considered in this study show that most of the initial fission product inventory would be retained within the containment by various fission product retention mechanisms. For the case where the crash cool-down system was credited but the auxiliary feed water systems were not credited, the total mass of volatile fission products released to the environment including stable and radioactive isotopes was about four times more than in the reference case, because fission products could be released directly from the PHTS to the environment through the Main Steam Safety Valves (MSSVs), bypassing the containment. For the case where the crash cool-down and auxiliary feed water systems were credited, the volatile fission product release to the environment was insignificant, because the fission product release was substantially mitigated by scrubbing in the water pool in the secondary side of the steam generator (SG). (authors)

  12. Analysis of the reasons for accidents and of protective measures against induced voltage on aerial electrical transmission lines

    SciTech Connect

    Misrikhanov, M. Sh.; Mirzaabdullaev, A. O.

    2009-01-15

    The problem of safety during work on aerial transmission lines under an induced voltage is examined. Results are presented from a study of the causes of accidents over the last 20 years in electrical grids in this country. A determination of different levels of induced voltage on disconnected aerial transmission lines as a function of their grounding scheme is proposed. The order of magnitudes for each level are given, along with approximate expressions for calculating them.

  13. [Emergency care for traffic accidents in Bavaria: current process analysis depending on hospital and emergency service structures].

    PubMed

    Lackner, C K; Bielmeier, S; Burghofer, K

    2010-03-01

    A change is emerging in the hospital landscape due to health political measures, which in consequence also influences the prehospital medical care in emergencies. The main focus of this study was to gather information about emergency medical care after traffic accidents on the basis of data from Bavarian emergency medical services. In 2006 there were 14,261 traffic accidents in Bavaria where an emergency doctor attended the scene. The patients were primarily cared for by land-based rescue services and air rescue services were only used in 19.1% of the cases. Of the patients involved in a traffic accident 47.6% were transported to a primary health care hospital. A prehospital interval of more than 60 min occurred in 20% of the missions. Of the patients 96.2% were transported to tertiary or maximum care hospital by air rescue services but emergency facilities were, however restricted to daylight hours. There was a further limitation due to the routine duty hours in hospitals as only 36.7% of accidents occurred during this time intervall. An increase of admission post trauma in maximum care clinics occurred from 2002 until 2006 while simultaneously the prehospital period was extended. In order to assure sufficient trauma care for seriously injured persons a continuous 24 h availability of emergency trauma facilities is necessary. For this purpose it is necessary to establish regional trauma networks between receiving hospitals as well as air rescue services at night time. Furthermore, a cost-efficient compensation of the structural, personnel and logistic expenses for the treatment of the severely injured has to be assured.

  14. Pipeline accident effects for hazardous liquid pipelines. Final report

    SciTech Connect

    Greenfeld, J.; Golub, E.; Dresnack, R.; Griffis, F.H.; Pignataro, L.J.

    1996-08-01

    The project team identified the factors that cause pipeline failures and the factors that effect accidents on hazardous liquid pipelines. Since the normalizing of the data was not possible, the authors of this report used indirect and inferential approaches in the analysis. The databases used for this analysis are LIQUID (accident data for 1968-1985) and LIQLCK (accident data for 1985-present). The main finding of this complete data on hazardous liquid accidents should be collected. Other conclusions are that prevention programs should be more effective, and pipe components such as valves, O-rings, gaskets and nipples are a significant source of potentially reducible accidents.

  15. Structural assessment of accident loads

    SciTech Connect

    Wagenblast, G.R., Westinghouse Hanford

    1996-05-28

    Structural assessments were made for specific accident loads for specific catch, receiver, and storage tanks. The evaluation herein represents level-of-effort order-of-magnitude estimates of limiting loads that would lead to collapse or rupture of the tank and unmitigated loss of confinement for the waste. Structural capacities were established using failure criteria. Compliance with codes such as ACI, ASCE, ASME, RCRA, UBC, WAC, and DOE Orders was `NOT` maintained. Normal code practice is to prevent failure with margins consistent with expected variations in loads and strengths and confidence in analysis techniques. The evaluation herein represent estimates of code limits without code load factors or code strength reduction factors, and loading beyond such a limit is considered as an onset of some failure mode. The exact nature of the failure mode and its relation to a safe condition is a judgment of the analyst. Consequently, these `RESULTS SHALL NOT BE USED TO ESTABLISH OPERATING OR SAFETY LOAD LIMITS FOR THESE TANKS`.

  16. A Scoping Analysis Of The Impact Of SiC Cladding On Late-Phase Accident Progression Involving Core–Concrete Interaction

    SciTech Connect

    Farmer, M. T.

    2015-11-01

    The overall objective of the current work is to carry out a scoping analysis to determine the impact of ATF on late phase accident progression; in particular, the molten core-concrete interaction portion of the sequence that occurs after the core debris fails the reactor vessel and relocates into containment. This additional study augments previous work by including kinetic effects that govern chemical reaction rates during core-concrete interaction. The specific ATF considered as part of this study is SiC-clad UO2.

  17. Evaluation of potential severe accidents during low power and shutdown operations at Surry, Unit 1: Analysis of core damage frequency from internal events during mid-loop operations. Appendix E (Sections E.9-E.16), Volume 2, Part 3B

    SciTech Connect

    Chu, T.L.; Musicki, Z.; Kohut, P.; Yang, J.; Bozoki, G.; Hsu, C.J.; Diamond, D.J.; Wong, S.M.; Bley, D.; Johnson, D.

    1994-06-01

    Traditionally, probabilistic risk assessments (PRA) of severe accidents in nuclear power plants have considered initiating events potentially occurring only during full power operation. Some previous screening analyses that were performed for other modes of operation suggested that risks during those modes were small relative to full power operation. However, more recent studies and operational experience have implied that accidents during low power and shutdown could be significant contributors to risk. Two plants, Surry (pressurized water reactor) and Grand Gulf (boiling water reactor), were selected as the plants to be studied. The objectives of the program are to assess the risks of severe accidents initiated during plant operational states other than full power operation and to compare the estimated core damage frequencies, important accident sequences and other qualitative and quantitative results with those accidents initiated during full power operation as assessed in NUREG-1150. The scope of the program includes that of a level-3 PRA. In phase 2, mid-loop operation was selected as the plant configuration to be analyzed based on the results of the phase 1 study. The objective of the phase 2 study is to perform a detailed analysis of the potential accident scenarios that may occur during mid-loop operation, and compare the results with those of NUREG-1150. The scope of the level-1 study includes plant damage state analysis, and uncertainty analysis. Volume 1 summarizes the results of the study. Internal events analysis is documented in Volume 2. It also contains an appendix that documents the part of the phase 1 study that has to do with POSs other than mid-loop operation. Internal fire and internal flood analyses are documented in Volumes 3 and 4. A separate study on seismic analysis, documented in Volume 5, was performed for the NRC by Future Resources Associates, Inc. Volume 6 documents the accident progression, source terms, and consequence analysis.

  18. Evaluation of potential severe accidents during low power and shutdown operations at Surry, Unit-1: Analysis of core damage frequency from internal events during mid-loop operations. Appendices F-H, Volume 2, Part 4

    SciTech Connect

    Chu, T.L.; Musicki, Z.; Kohut, P.; Yang, J.; Bozoki, G.; Hsu, C.J.; Diamond, D.J.; Bley, D.; Johnson, D.; Holmes, B.

    1994-06-01

    Traditionally, probabilistic risk assessments (PRA) of severe accidents in nuclear power plants have considered initiating events potentially occurring only during full power operation. Some previous screening analyses that were performed for other modes of operation suggested that risks during those modes were small relative to full power operation. However, more recent studies and operational experience have implied that accidents during low power and shutdown could be significant contributors to risk. Two plants, Surry (pressurized water reactor) and Grand Gulf (boiling water reactor), were selected as the plants to be studied. The objectives of the program are to assess the risks of severe accidents initiated during plant operational states other than full power operation and to compare the estimated core damage frequencies, important accident sequences and other qualitative and quantitative results with those accidents initiated during full power operation as assessed in NUREG-1150. The scope of the program includes that of a level-3 PRA. In phase 2, mid-loop operation was selected as the plant configuration to be analyzed based on the results of the phase 1 study. The objective of the phase 2 study is to perform a detailed analysis of the potential accident scenarios that may occur during mid-loop operation, and compare the results with those of NUREG-1150. The scope of the level-1 study includes plant damage state analysis, and uncertainty analysis. Volume 1 summarizes the results of the study. Internal events analysis is documented in Volume 2. It also contains an appendix that documents the part of the phase 1 study that has to do with POSs other than mid-loop operation. Internal fire and internal flood analyses are documented in Volumes 3 and 4. A separate study on seismic analysis, documented in Volume 5, was performed for the NRC by Future Resources Associates, Inc. Volume 6 documents the accident progression, source terms, and consequence analysis.

  19. Comparison of laser transit anemometry data analysis techniques

    NASA Technical Reports Server (NTRS)

    Humphreys, William M., Jr.; Gartrell, Luther R.

    1991-01-01

    Two techniques for the extraction of two-dimensional flow information from laser transit anemometry (LTA) data sets are presented and compared via a simulation study and experimental investigation. The methods are a probability density function (PDF) estimation technique and a marginal distribution analysis technique. The simulation study builds on the results of previous work and provides a quantification of the accuracy of both techniques for various LTA data acquisition scenarios. The experimental comparison consists of using an LTA system to survey the flow downstream of a turbulence generator in a small low-speed wind tunnel. The collected data sets are analyzed and compared.

  20. Repository preclosure accident scenarios

    SciTech Connect

    Yook, H.R.; Arbital, J.G.; Keeton, J.M.; Mosier, J.E.; Weaver, B.S.

    1984-09-01

    Waste-handling operations at a spent-fuel repository were investigated to identify operational accidents that could occur. The facility was subdivided, through systems engineering procedures, into individual operations that involve the waste and one specific component of the waste package, in one specific area of the handling facility. From this subdivision approximately 600 potential accidents involving waste package components were identified and then discussed. Supporting descriptive data included for each accident scenario are distance of drop, speed of collision, weight of package component, and weight of equipment involved. The energy of impact associated with each potential accident is calculated to provide a basis for comparison of the relative severities of all the accidents. The results and conclusions suggest approaches to accident consequence mitigation through waste package and facility design. 35 figures, 9 tables.

  1. Analysis of accident sequences and source terms at waste treatment and storage facilities for waste generated by U.S. Department of Energy Waste Management Operations, Volume 3: Appendixes C-H

    SciTech Connect

    Mueller, C.; Nabelssi, B.; Roglans-Ribas, J.

    1995-04-01

    This report contains the Appendices for the Analysis of Accident Sequences and Source Terms at Waste Treatment and Storage Facilities for Waste Generated by the U.S. Department of Energy Waste Management Operations. The main report documents the methodology, computational framework, and results of facility accident analyses performed as a part of the U.S. Department of Energy (DOE) Waste Management Programmatic Environmental Impact Statement (WM PEIS). The accident sequences potentially important to human health risk are specified, their frequencies are assessed, and the resultant radiological and chemical source terms are evaluated. A personal computer-based computational framework and database have been developed that provide these results as input to the WM PEIS for calculation of human health risk impacts. This report summarizes the accident analyses and aggregates the key results for each of the waste streams. Source terms are estimated and results are presented for each of the major DOE sites and facilities by WM PEIS alternative for each waste stream. The appendices identify the potential atmospheric release of each toxic chemical or radionuclide for each accident scenario studied. They also provide discussion of specific accident analysis data and guidance used or consulted in this report.

  2. Laser accidents: Being Prepared

    SciTech Connect

    Barat, K

    2003-01-24

    The goal of the Laser Safety Officer and any laser safety program is to prevent a laser accident from occurring, in particular an injury to a person's eyes. Most laser safety courses talk about laser accidents, causes, and types of injury. The purpose of this presentation is to present a plan for safety offices and users to follow in case of accident or injury from laser radiation.

  3. Transport aircraft accident dynamics

    NASA Technical Reports Server (NTRS)

    Cominsky, A.

    1982-01-01

    A study was carried out of 112 impact survivable jet transport aircraft accidents (world wide) of 27,700 kg (60,000 lb.) aircraft and up extending over the last 20 years. This study centered on the effect of impact and the follow-on events on aircraft structures and was confined to the approach, landing and takeoff segments of the flight. The significant characteristics, frequency of occurrence and the effect on the occupants of the above data base were studied and categorized with a view to establishing typical impact scenarios for use as a basis of verifying the effectiveness of potential safety concepts. Studies were also carried out of related subjects such as: (1) assessment of advanced materials; (2) human tolerance to impact; (3) merit functions for safety concepts; and (4) impact analysis and test methods.

  4. Fuel handling accident analysis for the University of Missouri Research Reactor's High Enriched Uranium to Low Enriched Uranium fuel conversion initiative

    NASA Astrophysics Data System (ADS)

    Rickman, Benjamin

    In accordance with the 1986 amendment concerning licenses for research and test reactors, the MU Research Reactor (MURR) is planning to convert from using High-Enriched Uranium (HEU) fuel to the use of Low-Enriched Uranium (LEU) fuel. Since the approval of a new LEU fuel that could meet the MURR's performance demands, the next phase of action for the fuel conversion process is to create a new Safety Analysis Report (SAR) with respect to the LEU fuel. A component of the SAR includes the Maximum Hypothetical Accident (MHA) and accidents that qualify under the class of Fuel Handling Accidents (FHA). In this work, the dose to occupational staff at the MURR is calculated for the FHAs. The radionuclide inventory for the proposed LEU fuel was calculated using the ORIGEN2 point-depletion code linked to the MURR neutron spectrum. The MURR spectrum was generated from a Monte Carlo Neutron transPort (MCNP) simulation. The coupling of these codes create MONTEBURNS, a time-dependent burnup code. The release fraction from each FHA within this analysis was established by the methodology of the 2006 HEU SAR, which was accepted by the NRC. The actual dose methodology was not recorded in the HEU SAR, so a conservative path was chosen. In compliance to NUREG 1537, when new methodology is used in a HEU to LEU analysis, it is necessary to re-evaluate the HEU accident. The Total Effective Dose Equivalent (TEDE) values were calculated in addition to the whole body dose and thyroid dose to operation personnel. The LEU FHA occupational TEDE dose was 349 mrem which is under the NRC regulatory occupational dose limit of 5 rem TEDE, and under the LEU MHA limit of 403 mrem. The re-evaluated HEU FHA occupational TEDE dose was 235 mrem, which is above the HEU MHA TEDE dose of 132 mrem. Since the new methodology produces a dose that is larger than the HEU MHA, we can safely assume that it is more conservative than the previous, unspecified dose.

  5. [Accidents with the "paraglider"].

    PubMed

    Lang, T H; Dengg, C; Gabl, M

    1988-09-01

    With a collective of 46 patients we show the details and kinds of accidents caused by paragliding. The base for the casuistry of the accidents was a questionnaire which was answered by most of the injured persons. These were questions about the theoretical and practical training, the course of the flight during the different phases, and the subjective point of view of the course of the accident. The patterns of the injuries showed a high incidence of injuries of the spinal column and high risks for the ankles. At the end, we give some advice how to prevent these accidents.

  6. Accident mortality among children

    PubMed Central

    Swaroop, S.; Albrecht, R. M.; Grab, B.

    1956-01-01

    The authors present statistics on mortality from accidents, with special reference to those relating to the age-group 1-19 years. For a number of countries figures are given for the proportional mortality from accidents (the number of accident deaths expressed as a percentage of the number of deaths from all causes) and for the specific death-rates, per 100 000 population, from all causes of death, from selected causes, from all causes of accidents, and from various types of accident. From these figures it appears that, in most countries, accidents are becoming relatively increasingly prominent as a cause of death in childhood, primarily because of the conquest of other causes of death—such as infectious and parasitic diseases, which formerly took a heavy toll of children and adolescents—but also to some extent because the death-rate from motor-vehicle accidents is rising and cancelling out the reduction in the rate for other causes of accidental death. In the authors' opinion, further epidemiological investigations into accident causation are required for the purpose of devising quicker and more effective methods of accident prevention. PMID:13383361

  7. Road accidents and business cycles in Spain.

    PubMed

    Rodríguez-López, Jesús; Marrero, Gustavo A; González, Rosa Marina; Leal-Linares, Teresa

    2016-11-01

    This paper explores the causes behind the downturn in road accidents in Spain across the last decade. Possible causes are grouped into three categories: Institutional factors (a Penalty Point System, PPS, dating from 2006), technological factors (active safety and passive safety of vehicles), and macroeconomic factors (the Great recession starting in 2008, and an increase in fuel prices during the spring of 2008). The PPS has been blessed by incumbent authorities as responsible for the decline of road fatalities in Spain. Using cointegration techniques, the GDP growth rate, the fuel price, the PPS, and technological items embedded in motor vehicles appear to be statistically significantly related with accidents. Importantly, PPS is found to be significant in reducing fatal accidents. However, PPS is not significant for non-fatal accidents. In view of these results, we conclude that road accidents in Spain are very sensitive to the business cycle, and that the PPS influenced the severity (fatality) rather than the quantity of accidents in Spain. Importantly, technological items help explain a sizable fraction in accidents downturn, their effects dating back from the end of the nineties.

  8. Basic Sequence Analysis Techniques for Use with Audit Trail Data

    ERIC Educational Resources Information Center

    Judd, Terry; Kennedy, Gregor

    2008-01-01

    Audit trail analysis can provide valuable insights to researchers and evaluators interested in comparing and contrasting designers' expectations of use and students' actual patterns of use of educational technology environments (ETEs). Sequence analysis techniques are particularly effective but have been neglected to some extent because of real…

  9. Regional environmental analysis and management: New techniques for current problems

    NASA Technical Reports Server (NTRS)

    Honea, R. B.; Paludan, C. T. N.

    1974-01-01

    Advances in data acquisition and processing procedures for regional environmental analysis are discussed. Automated and semi-automated techniques employing Earth Resources Technology Satellite data and conventional data sources are presented. Experiences are summarized. The ERTS computer compatible tapes provide a very complete and flexible record of earth resources data and represent a viable medium to enhance regional environmental analysis research.

  10. Considerations and Techniques for the Analysis of NAEP Data.

    ERIC Educational Resources Information Center

    Johnson, Eugene G.

    1989-01-01

    The effects of certain characteristics (e.g., sample design) of National Assessment of Educational Progress (NAEP) data on statistical analysis techniques are considered. Ignoring special features of NAEP data and proceeding with a standard analysis can produce inferences that underestimate the true variability and overestimate the true degrees of…

  11. Considerations and Techniques for the Analysis of NAEP Data.

    ERIC Educational Resources Information Center

    Johnson, Eugene

    The special characteristics of the data from the National Assessment of Educational Progress (NAEP) that affect the validity of conventional techniques of statistical analysis are considered. In contrast to the assumptions underlying standard methods of statistical analysis, the NAEP samples are obtained via a stratified multi-stage probability…

  12. New Flutter Analysis Technique for CFD-based Unsteady Aeroelasticity

    NASA Technical Reports Server (NTRS)

    Pak, Chan-gi; Jutte, Christine V.

    2009-01-01

    This paper presents a flutter analysis technique for the transonic flight regime. The technique uses an iterative approach to determine the critical dynamic pressure for a given mach number. Unlike other CFD-based flutter analysis methods, each iteration solves for the critical dynamic pressure and uses this value in subsequent iterations until the value converges. This process reduces the iterations required to determine the critical dynamic pressure. To improve the accuracy of the analysis, the technique employs a known structural model, leaving only the aerodynamic model as the unknown. The aerodynamic model is estimated using unsteady aeroelastic CFD analysis combined with a parameter estimation routine. The technique executes as follows. The known structural model is represented as a finite element model. Modal analysis determines the frequencies and mode shapes for the structural model. At a given mach number and dynamic pressure, the unsteady CFD analysis is performed. The output time history of the surface pressure is converted to a nodal aerodynamic force vector. The forces are then normalized by the given dynamic pressure. A multi-input multi-output parameter estimation software, ERA, estimates the aerodynamic model through the use of time histories of nodal aerodynamic forces and structural deformations. The critical dynamic pressure is then calculated using the known structural model and the estimated aerodynamic model. This output is used as the dynamic pressure in subsequent iterations until the critical dynamic pressure is determined. This technique is demonstrated on the Aerostructures Test Wing-2 model at NASA's Dryden Flight Research Center.

  13. Learning lessons from Natech accidents - the eNATECH accident database

    NASA Astrophysics Data System (ADS)

    Krausmann, Elisabeth; Girgin, Serkan

    2016-04-01

    When natural hazards impact industrial facilities that house or process hazardous materials, fires, explosions and toxic releases can occur. This type of accident is commonly referred to as Natech accident. In order to prevent the recurrence of accidents or to better mitigate their consequences, lessons-learned type studies using available accident data are usually carried out. Through post-accident analysis, conclusions can be drawn on the most common damage and failure modes and hazmat release paths, particularly vulnerable storage and process equipment, and the hazardous materials most commonly involved in these types of accidents. These analyses also lend themselves to identifying technical and organisational risk-reduction measures that require improvement or are missing. Industrial accident databases are commonly used for retrieving sets of Natech accident case histories for further analysis. These databases contain accident data from the open literature, government authorities or in-company sources. The quality of reported information is not uniform and exhibits different levels of detail and accuracy. This is due to the difficulty of finding qualified information sources, especially in situations where accident reporting by the industry or by authorities is not compulsory, e.g. when spill quantities are below the reporting threshold. Data collection has then to rely on voluntary record keeping often by non-experts. The level of detail is particularly non-uniform for Natech accident data depending on whether the consequences of the Natech event were major or minor, and whether comprehensive information was available for reporting. In addition to the reporting bias towards high-consequence events, industrial accident databases frequently lack information on the severity of the triggering natural hazard, as well as on failure modes that led to the hazmat release. This makes it difficult to reconstruct the dynamics of the accident and renders the development of

  14. United States Department of Energy severe accident research following the Fukushima Daiichi accidents

    SciTech Connect

    Farmer, M. T.; Corradini, M.; Rempe, J.; Reister, R.; Peko, D.

    2016-11-02

    The U.S. Department of Energy (DOE) has played a major role in the U.S. response to the events at Fukushima Daiichi. During the first several weeks following the accident, U.S. assistance efforts were guided by results from a significant and diverse set of analyses. In the months that followed, a coordinated analysis activity aimed at gaining a more thorough understanding of the accident sequence was completed using laboratory-developed, system-level best-estimate accident analysis codes, while a parallel analysis was conducted by U.S. industry. A comparison of predictions for Unit 1 from these two studies indicated significant differences between MAAP and MELCOR results for key plant parameters, such as in-core hydrogen production. On that basis, a crosswalk was completed to determine the key modeling variations that led to these differences. In parallel with these activities, it became clear that there was a need to perform a technology gap evaluation on accident-tolerant components and severe accident analysis methodologies with the goal of identifying any data and/or knowledge gaps that may exist given the current state of light water reactor (LWR) severe accident research and augmented by insights from Fukushima. In addition, there is growing international recognition that data from Fukushima could significantly reduce uncertainties related to severe accident progression, particularly for boiling water reactors. On these bases, a group of U. S. experts in LWR safety and plant operations was convened by the DOE Office of Nuclear Energy (DOE-NE) to complete technology gap analysis and Fukushima forensics data needs identification activities. The results from these activities were used as the basis for refining DOE-NE's severe accident research and development (R&D) plan. Finally, this paper provides a high-level review of DOE-sponsored R&D efforts in these areas, including planned activities on accident-tolerant components and accident analysis methods.

  15. United States Department of Energy severe accident research following the Fukushima Daiichi accidents

    DOE PAGES

    Farmer, M. T.; Corradini, M.; Rempe, J.; ...

    2016-11-02

    The U.S. Department of Energy (DOE) has played a major role in the U.S. response to the events at Fukushima Daiichi. During the first several weeks following the accident, U.S. assistance efforts were guided by results from a significant and diverse set of analyses. In the months that followed, a coordinated analysis activity aimed at gaining a more thorough understanding of the accident sequence was completed using laboratory-developed, system-level best-estimate accident analysis codes, while a parallel analysis was conducted by U.S. industry. A comparison of predictions for Unit 1 from these two studies indicated significant differences between MAAP and MELCORmore » results for key plant parameters, such as in-core hydrogen production. On that basis, a crosswalk was completed to determine the key modeling variations that led to these differences. In parallel with these activities, it became clear that there was a need to perform a technology gap evaluation on accident-tolerant components and severe accident analysis methodologies with the goal of identifying any data and/or knowledge gaps that may exist given the current state of light water reactor (LWR) severe accident research and augmented by insights from Fukushima. In addition, there is growing international recognition that data from Fukushima could significantly reduce uncertainties related to severe accident progression, particularly for boiling water reactors. On these bases, a group of U. S. experts in LWR safety and plant operations was convened by the DOE Office of Nuclear Energy (DOE-NE) to complete technology gap analysis and Fukushima forensics data needs identification activities. The results from these activities were used as the basis for refining DOE-NE's severe accident research and development (R&D) plan. Finally, this paper provides a high-level review of DOE-sponsored R&D efforts in these areas, including planned activities on accident-tolerant components and accident analysis methods.« less

  16. Probabilistic methods for identification of significant accident sequences in loop-type LMFBRs

    SciTech Connect

    Jamali, K M.A.

    1983-06-01

    The aim of the Probabilistic Accident Progression Analysis (PAPA) described herein is to establish a framework for better use of the probability measure; first, as a basis for deterministic calculations, and second, as a part of a comprehensive method for risk assessment in its own right. The achievement of this goal rests on: (1) improvements in the existing approaches for acquisition and analysis of accident sequences; (2) defining a new measure of probabilistic importance that aids in the ranking of sequences of highly uncertain events; and (3) implementation of new techniques for quantification of dependent failures of similar components. The existing techniques related to the above three topics are discussed and the state of the art is reviewed. The PAPA approach is described. The techniques of PAPA are applied to a class of Protected Transients (transients in which the reactor is successfully shutdown) in the Clinch River Breeder Reactor Plant (CRBRP). The results of the application of these techniques are described.

  17. Analysis of main steam isolation valve leakage in design basis accidents using MELCOR 1.8.6 and RADTRAD.

    SciTech Connect

    Salay, Michael; Kalinich, Donald A.; Gauntt, Randall O.; Radel, Tracy E.

    2008-10-01

    Analyses were performed using MELCOR and RADTRAD to investigate main steam isolation valve (MSIV) leakage behavior under design basis accident (DBA) loss-of-coolant (LOCA) conditions that are presumed to have led to a significant core melt accident. Dose to the control room, site boundary and LPZ are examined using both approaches described in current regulatory guidelines as well as analyses based on best estimate source term and system response. At issue is the current practice of using containment airborne aerosol concentrations as a surrogate for the in-vessel aerosol concentration that exists in the near vicinity of the MSIVs. This study finds current practice using the AST-based containment aerosol concentrations for assessing MSIV leakage is non-conservative and conceptually in error. A methodology is proposed that scales the containment aerosol concentration to the expected vessel concentration in order to preserve the simplified use of the AST in assessing containment performance under assumed DBA conditions. This correction is required during the first two hours of the accident while the gap and early in-vessel source terms are present. It is general practice to assume that at {approx}2hrs, recovery actions to reflood the core will have been successful and that further core damage can be avoided. The analyses performed in this study determine that, after two hours, assuming vessel reflooding has taken place, the containment aerosol concentration can then conservatively be used as the effective source to the leaking MSIV's. Recommendations are provided concerning typical aerosol removal coefficients that can be used in the RADTRAD code to predict source attenuation in the steam lines, and on robust methods of predicting MSIV leakage flows based on measured MSIV leakage performance.

  18. [The comparative analysis of gene and structural somatic mutations in inhabitants of Orel district areas contaminated with radionuclides as a result of Chernobyl accident].

    PubMed

    Sevan'kaev, A V; Zamulaeva, I A; Mikhaĭlova, G F; Potetnia, O I; Tsepenko, V V; Khvostunov, I K; Golub, E V; Piatenko, V S; Pozdyshkina, O V; Vereshchagina, A O; Smirnova, S G; Orlova, N V; Saenko, A S; Parshin, V S

    2006-01-01

    The results of comparative analysis of gene and structural mutations found in peripheral blood lymphocytes of inhabitants of Orel district areas contaminated with radionuclides as a result of Chernobyl accident are presented. The average level of 137Cs contamination in those areas ranged about 22-113 kBq/m2. In the study group was found the enhanced frequency of somatic cells with gene and structural mutations compared with laboratory control level by synchronous applying a T-cell receptor (TCR) loci mutation assay and cytogenetic analysis of unstable aberrations. The case-control comparison was carried out using the measured mutation frequencies and cases of various thyroid gland sickness recognized by ultrasonic examination. The cytogenetic assay did not show the statistical difference between healthy group and subjects with thyroid gland sickness. The average frequency of TCR loci mutation cells in the subjects with thyroid gland sickness was found to be statistically higher comparing with healthy persons. This finding was true for each study region and for Orel district in total. The subgroup of subject exposed in utero in 1986, soon after accident was analyzed. Both cytogenetic and TCR loci mutation assays shown enhancement of average mutation frequency in somatic cells in the subjects of this subgroup with thyroid gland sickness comparing with healthy persons.

  19. Comparative analysis of PA-31-350 Chieftain (N44LV) accident and NASA crash test data

    NASA Technical Reports Server (NTRS)

    Hayduk, R. J.

    1979-01-01

    A full scale, controlled crash test to simulate the crash of a Piper PA-31-350 Chieftain airplane is described. Comparisons were performed between the simulated crash and the actual crash in order to assess seat and floor behavior, and to estimate the acceleration levels experienced in the craft at the time of impact. Photographs, acceleration histories, and the tested airplane crash data is used to augment the accident information to better define the crash conditions. Measured impact parameters are presented along with flight path velocity and angle in relation to the impact surface.

  20. S-192 analysis: Conventional and special data processing techniques. [Michigan

    NASA Technical Reports Server (NTRS)

    Nalepka, R. F. (Principal Investigator); Morganstern, J.; Cicone, R.; Sarno, J.; Lambeck, P.; Malila, W.

    1975-01-01

    The author has identified the following significant results. Multispectral scanner data gathered over test sites in southeast Michigan were analyzed. This analysis showed the data to be somewhat deficient especially in terms of the limited signal range in most SDOs and also in regard to SDO-SDO misregistration. Further analysis showed that the scan line straightening algorithm increased the misregistration of the data. Data were processed using the conic format. The effects of such misregistration on classification accuracy was analyzed via simulation and found to be significant. Results of employing conventional as well as special, unresolved object, processing techniques were disappointing due, at least in part, to the limited signal range and noise content of the data. Application of a second class of special processing techniques, signature extension techniques, yielded better results. Two of the more basic signature extension techniques seemed to be useful in spite of the difficulties.

  1. Equations for determining aircraft motions for accident data

    NASA Technical Reports Server (NTRS)

    Bach, R. E., Jr.; Wingrove, R. C.

    1980-01-01

    Procedures for determining a comprehensive accident scenario from a limited data set are reported. The analysis techniques accept and process data from either an Air Traffic Control radar tracking system or a foil flight data recorder. Local meteorological information at the time of the accident and aircraft performance data are also utilized. Equations for the desired aircraft motions and forces are given in terms of elements of the measurement set and certain of their time derivatives. The principal assumption made is that aircraft side force and side-slip angle are negligible. An estimation procedure is outlined for use with each data source. For the foil case, a discussion of exploiting measurement redundancy is given. Since either formulation requires estimates of measurement time derivatives, an algorithm for least squares smoothing is provided.

  2. Analysis techniques used on field degraded photovoltaic modules

    SciTech Connect

    Hund, T.D.; King, D.L.

    1995-09-01

    Sandia National Laboratory`s PV System Components Department performs comprehensive failure analysis of photovoltaic modules after extended field exposure at various sites around the world. A full spectrum of analytical techniques are used to help identify the causes of degradation. The techniques are used to make solder fatigue life predictions for PV concentrator modules, identify cell damage or current mismatch, and measure the adhesive strength of the module encapsulant.

  3. Applications of Electromigration Techniques: Applications of Electromigration Techniques in Food Analysis

    NASA Astrophysics Data System (ADS)

    Wieczorek, Piotr; Ligor, Magdalena; Buszewski, Bogusław

    Electromigration techniques, including capillary electrophoresis (CE), are widely used for separation and identification of compounds present in food products. These techniques may also be considered as alternate and complementary with respect to commonly used analytical techniques, such as high-performance liquid chromatography (HPLC), or gas chromatography (GC). Applications of CE concern the determination of high-molecular compounds, like polyphenols, including flavonoids, pigments, vitamins, food additives (preservatives, antioxidants, sweeteners, artificial pigments) are presented. Also, the method developed for the determination of proteins and peptides composed of amino acids, which are basic components of food products, are studied. Other substances such as carbohydrates, nucleic acids, biogenic amines, natural toxins, and other contaminations including pesticides and antibiotics are discussed. The possibility of CE application in food control laboratories, where analysis of the composition of food and food products are conducted, is of great importance. CE technique may be used during the control of technological processes in the food industry and for the identification of numerous compounds present in food. Due to the numerous advantages of the CE technique it is successfully used in routine food analysis.

  4. Current controversies in child accident prevention. An analysis of some areas of dispute in the prevention of child trauma.

    PubMed

    Pearn, J H

    1985-12-01

    The rate of serious child trauma has not been significantly reduced in the last two decades. During this time, both infant mortality rates and the total child death rate have fallen by 30%. Child trauma, as a relative contributor to child mortality in general, continues to increase. Effective prevention depends on a detailed understanding of causes, an appraisal of options, and cost-benefit audit of intervention programmes. Controversial themes are common in accident prevention work; controversies relating to child safety result from both an absence of data about detailed causes, and from philosophical conflicts about whose responsibility it is to prevent child trauma, and who will bear the cost. Five controversial areas have been selected and are discussed to illustrate these current problems. These are the inevitability of accidents, the loss of personal freedom that occurs in the regulation of a safe environment, "drownproofing" of infants, questions of sporting injuries involving children and the progressive upgrading of rules to make sports safer, and problems relating to the assessment of true exposure risks.

  5. Comparison of perceived and modelled geographical access to accident and emergency departments: a cross-sectional analysis from the Caerphilly Health and Social Needs Study

    PubMed Central

    Fone, David L; Christie, Stephen; Lester, Nathan

    2006-01-01

    Background Assessment of the spatial accessibility of hospital accident and emergency departments as perceived by local residents has not previously been investigated. Perceived accessibility may affect where, when, and whether potential patients attend for treatment. Using data on 11,853 respondents to a population survey in Caerphilly county borough, Wales, UK, we present an analysis comparing the accessibility of accident and emergency departments as reported by local residents and drive-time to the nearest accident and emergency department modelled using a geographical information system (GIS). Results Median drive-times were significantly shorter in the lowest perceived access category and longer in the best perceived access category (p < 0.001). The perceived access and GIS modelled drive-time variables were positively correlated (Spearman's rank correlation coefficient, r = 0.38, p < 0.01). The strongest correlation was found for respondents living in areas in which nearly all households had a car or van (r = 0.47, p < 0.01). Correlations were stronger among respondents reporting good access to public transport and among those reporting a recent accident and emergency attendance for injury treatment compared to other respondents. Correlation coefficients did not vary substantially by levels of household income. Drive-time, road distance and straight-line distance were highly inter-correlated and substituting road distance or straight-line distance as the GIS modelled spatial accessibility measure only marginally decreased the magnitude of the correlations between perceived and GIS modelled access. Conclusion This study provides evidence that the accessibility of hospital-based health care services as perceived by local residents is related to measures of spatial accessibility modelled using GIS. For studies that aim to model geographical separation in a way that correlates well with the perception of local residents, there may be minimal advantage in using

  6. Behavior of an heterogeneous annular FBR core during an unprotected loss of flow accident: Analysis of the primary phase with SAS-SFR

    SciTech Connect

    Massara, S.; Schmitt, D.; Bretault, A.; Lemasson, D.; Darmet, G.; Verwaerde, D.; Struwe, D.; Pfrang, W.; Ponomarev, A.

    2012-07-01

    In the framework of a substantial improvement on FBR core safety connected to the development of a new Gen IV reactor type, heterogeneous core with innovative features are being carefully analyzed in France since 2009. At EDF R and D, the main goal is to understand whether a strong reduction of the Na-void worth - possibly attempting a negative value - allows a significant improvement of the core behavior during an unprotected loss of flow accident. Also, the physical behavior of such a core is of interest, before and beyond the (possible) onset of Na boiling. Hence, a cutting-edge heterogeneous design, featuring an annular shape, a Na-plena with a B{sub 4}C plate and a stepwise modulation of fissile core heights, was developed at EDF by means of the SDDS methodology, with a total Na-void worth of -1 $. The behavior of such a core during the primary phase of a severe accident, initiated by an unprotected loss of flow, is analyzed by means of the SAS-SFR code. This study is carried-out at KIT and EDF, in the framework of a scientific collaboration on innovative FBR severe accident analyses. The results show that the reduction of the Na-void worth is very effective, but is not sufficient alone to avoid Na-boiling and, hence, to prevent the core from entering into the primary phase of a severe accident. Nevertheless, the grace time up to boiling onset is greatly enhanced in comparison to a more traditional homogeneous core design, and only an extremely low fraction of the fuel (<0.1%) enters into melting at the end of this phase. A sensitivity analysis shows that, due to the inherent neutronic characteristics of such a core, the gagging scheme plays a major role on the core behavior: indeed, an improved 4-zones gagging scheme, associated with an enhanced control rod drive line expansion feed-back effect, finally prevents the core from entering into sodium boiling. This major conclusion highlights both the progress already accomplished and the need for more detailed

  7. Review and classification of variability analysis techniques with clinical applications.

    PubMed

    Bravi, Andrea; Longtin, André; Seely, Andrew J E

    2011-10-10

    Analysis of patterns of variation of time-series, termed variability analysis, represents a rapidly evolving discipline with increasing applications in different fields of science. In medicine and in particular critical care, efforts have focussed on evaluating the clinical utility of variability. However, the growth and complexity of techniques applicable to this field have made interpretation and understanding of variability more challenging. Our objective is to provide an updated review of variability analysis techniques suitable for clinical applications. We review more than 70 variability techniques, providing for each technique a brief description of the underlying theory and assumptions, together with a summary of clinical applications. We propose a revised classification for the domains of variability techniques, which include statistical, geometric, energetic, informational, and invariant. We discuss the process of calculation, often necessitating a mathematical transform of the time-series. Our aims are to summarize a broad literature, promote a shared vocabulary that would improve the exchange of ideas, and the analyses of the results between different studies. We conclude with challenges for the evolving science of variability analysis.

  8. Review and classification of variability analysis techniques with clinical applications

    PubMed Central

    2011-01-01

    Analysis of patterns of variation of time-series, termed variability analysis, represents a rapidly evolving discipline with increasing applications in different fields of science. In medicine and in particular critical care, efforts have focussed on evaluating the clinical utility of variability. However, the growth and complexity of techniques applicable to this field have made interpretation and understanding of variability more challenging. Our objective is to provide an updated review of variability analysis techniques suitable for clinical applications. We review more than 70 variability techniques, providing for each technique a brief description of the underlying theory and assumptions, together with a summary of clinical applications. We propose a revised classification for the domains of variability techniques, which include statistical, geometric, energetic, informational, and invariant. We discuss the process of calculation, often necessitating a mathematical transform of the time-series. Our aims are to summarize a broad literature, promote a shared vocabulary that would improve the exchange of ideas, and the analyses of the results between different studies. We conclude with challenges for the evolving science of variability analysis. PMID:21985357

  9. [Accidents and injuries at work].

    PubMed

    Standke, W

    2014-06-01

    In the case of an accident at work, the person concerned is insured by law according to the guidelines of the Sozialgesetzbuch VII as far as the injuries have been caused by this accident. The most important source of information on the incident in question is the accident report that has to be sent to the responsible institution for statutory accident insurance and prevention by the employer, if the accident of the injured person is fatal or leads to an incapacity to work for more than 3 days (= reportable accident). Data concerning accidents like these are sent to the Deutsche Gesetzliche Unfallversicherung (DGUV) as part of a random sample survey by the institutions for statutory accident insurance and prevention and are analyzed statistically. Thus the key issues of accidents can be established and used for effective prevention. Although the success of effective accident prevention is undisputed, there were still 919,025 occupational accidents in 2011, with clear gender-related differences. Most occupational accidents involve the upper and lower extremities. Accidents are analyzed comprehensively and the results are published and made available to all interested parties in an effort to improve public awareness of possible accidents. Apart from reportable accidents, data on the new occupational accident pensions are also gathered and analyzed statistically. Thus, additional information is gained on accidents with extremely serious consequences and partly permanent injuries for the accident victims.

  10. Analysis automation with paving: A new quadrilateral meshing technique

    SciTech Connect

    Blacker, T.D. ); Stephenson, M.B.; Canann, S. )

    1990-01-01

    This paper describes the impact of paving, a new automatic mesh generation algorithm, on the analysis portion of the design process. Paving generates an all-quadrilateral mesh in arbitrary 2D geometries. The paving technique significantly impacts the analysis process by drastically reducing the time and expertise requirements of traditional mesh generation. Paving produces a high quality mesh based on geometric boundary definitions and user specified element sizing constraints. In this paper we describe the paving algorithm, discuss varying aspects of the impact of the technique on design automation, and elaborate on current research into 3D all-hexahedral mesh generation. 11 refs., 10 figs.

  11. Evaluation of potential severe accidents during low power and shutdown operations at Surry, Unit-1: Analysis of core damage frequency from internal events during mid-loop operations. Appendix I, Volume 2, Part 5

    SciTech Connect

    Chu, T.L.; Musicki, Z.; Kohut, P.; Yang, J.; Bozoki, G.; Hsu, C.J.; Diamond, D.J.; Bley, D.; Johnson, D.; Holmes, B.

    1994-06-01

    Traditionally, probabilistic risk assessments (PRA) of severe accidents in nuclear power plants have considered initiating events potentially occurring only during full power operation. Some previous screening analyses that were performed for other modes of operation suggested that risks during those modes were small relative to full power operation. However, more recent studies and operational experience have implied that accidents during low power and shutdown could be significant contributors to risk. During 1989, the Nuclear Regulatory Commission (NRC) initiated an extensive program to carefully examine the potential risks during low power and shutdown operations. The program includes two parallel projects being performed by Brookhaven National Lab. (BNL) and Sandia National Labs. (SNL). Two plants, Surry (pressurized water reactor) and Grand Gulf (boiling water reactor), were selected as the plants to be studied. The objectives of the program are to assess the risks of severe accidents initiated during plant operational states other than full power operation and to compare the estimated core damage frequencies, important accident sequences and other qualitative and quantitative results with those accidents initiated during full power operation as assessed in NUREG-1150. The objective of this volume of the report is to document the approach utilized in the level-1 internal events PRA for the Surry plant, and discuss the results obtained. A phased approach was used in the level-1 program. In phase 1, which was completed in Fall 1991, a coarse screening analysis examining accidents initiated by internal events (including internal fire and flood) was performed for all plant operational states (POSs). The objective of the phase 1 study was to identify potential vulnerable plant configurations, to characterize (on a high, medium, or low basis) the potential core damage accident scenarios, and to provide a foundation for a detailed phase 2 analysis.

  12. iWitness pollution map: crowdsourcing petrochemical accident research.

    PubMed

    Bera, Risha; Hrybyk, Anna

    2013-01-01

    Community members living near any one of Louisiana's 160 chemical plants or refineries have always said that accidents occurring in these petrochemical facilities significantly impact their health and safety. This article reviews the iWitness Pollution Map tool and Rapid Response Team (RRT) approach led by the Louisiana Bucket Brigade, an environmental nonprofit group, and their effectiveness in documenting these health and safety impacts during petrochemical accidents. Analysis of a January 2013 RRT deployment in Chalmette, LA, showed increased documentation of current petrochemical accidents and suggested increased preparedness to report future accidents. The RRT model encourages government response and enforcement agencies to integrate with organized community groups to fully document the impacts during ongoing accidents, lead a more timely response to the accident, and prevent future accidents from occurring.

  13. Photomorphic analysis techniques: An interim spatial analysis using satellite remote sensor imagery and historical data

    NASA Technical Reports Server (NTRS)

    Keuper, H. R.; Peplies, R. W.; Gillooly, R. P.

    1977-01-01

    The use of machine scanning and/or computer-based techniques to provide greater objectivity in the photomorphic approach was investigated. Photomorphic analysis and its application in regional planning are discussed. Topics included: delineation of photomorphic regions; inadequacies of existing classification systems; tonal and textural characteristics and signature analysis techniques; pattern recognition and Fourier transform analysis; and optical experiments. A bibliography is included.

  14. Performance analysis of multiple PRF technique for ambiguity resolution

    NASA Technical Reports Server (NTRS)

    Chang, C. Y.; Curlander, J. C.

    1992-01-01

    For short wavelength spaceborne synthetic aperture radar (SAR), ambiguity in Doppler centroid estimation occurs when the azimuth squint angle uncertainty is larger than the azimuth antenna beamwidth. Multiple pulse recurrence frequency (PRF) hopping is a technique developed to resolve the ambiguity by operating the radar in different PRF's in the pre-imaging sequence. Performance analysis results of the multiple PRF technique are presented, given the constraints of the attitude bound, the drift rate uncertainty, and the arbitrary numerical values of PRF's. The algorithm performance is derived in terms of the probability of correct ambiguity resolution. Examples, using the Shuttle Imaging Radar-C (SIR-C) and X-SAR parameters, demonstrate that the probability of correct ambiguity resolution obtained by the multiple PRF technique is greater than 95 percent and 80 percent for the SIR-C and X-SAR applications, respectively. The success rate is significantly higher than that achieved by the range cross correlation technique.

  15. A comparative analysis of soft computing techniques for gene prediction.

    PubMed

    Goel, Neelam; Singh, Shailendra; Aseri, Trilok Chand

    2013-07-01

    The rapid growth of genomic sequence data for both human and nonhuman species has made analyzing these sequences, especially predicting genes in them, very important and is currently the focus of many research efforts. Beside its scientific interest in the molecular biology and genomics community, gene prediction is of considerable importance in human health and medicine. A variety of gene prediction techniques have been developed for eukaryotes over the past few years. This article reviews and analyzes the application of certain soft computing techniques in gene prediction. First, the problem of gene prediction and its challenges are described. These are followed by different soft computing techniques along with their application to gene prediction. In addition, a comparative analysis of different soft computing techniques for gene prediction is given. Finally some limitations of the current research activities and future research directions are provided.

  16. Analysis of criticality accident alarm system coverage of the X-744G, X-744H, X-342/344A and X-343 facilities at the Portsmouth Gaseous Diffusion Plant

    SciTech Connect

    Dobelbower, M.C.; Woollard, J.; Lee, B.L. Jr.; Tayloe, R.W. Jr.

    1995-09-01

    Additional services for the uranium enrichment cascade process, such as UF{sub 6} feed, sampling, and material storage are provided by several ancillary Uranium Material Handling (UMH) facilities at the PORTS site. These facilities include the X-343 Feed Vaporization and Sampling Facility, the X-744G Bulk Non-Uranium Enrichment Service Activity (UESA) Storage Building, the X-744H Waste Separation and Storage Facility, the X-344A Toll Enrichment Services Facility and the X-342A Feed Vaporization and Fluorine Generation Facility. As uranium operations are performed within these facilities, the potential for a criticality accident exists. In the event of a criticality accident within a process facility at PORTS, a Criticality Accident Alarm System (CAAS) is in place to detect the criticality accident and sound an alarm. In this report, an analysis was performed to provide verification that the existing CAAS at PORTS provides complete criticality accident coverage in the X-343, X-744G. X-744H. X-344A and X-342A facilities. The analysis has determined that all of the above-mentioned facilities have complete CAAS coverage.

  17. LOFT Debriefings: An Analysis of Instructor Techniques and Crew Participation

    NASA Technical Reports Server (NTRS)

    Dismukes, R. Key; Jobe, Kimberly K.; McDonnell, Lori K.

    1997-01-01

    This study analyzes techniques instructors use to facilitate crew analysis and evaluation of their Line-Oriented Flight Training (LOFT) performance. A rating instrument called the Debriefing Assessment Battery (DAB) was developed which enables raters to reliably assess instructor facilitation techniques and characterize crew participation. Thirty-six debriefing sessions conducted at five U.S. airlines were analyzed to determine the nature of instructor facilitation and crew participation. Ratings obtained using the DAB corresponded closely with descriptive measures of instructor and crew performance. The data provide empirical evidence that facilitation can be an effective tool for increasing the depth of crew participation and self-analysis of CRM performance. Instructor facilitation skill varied dramatically, suggesting a need for more concrete hands-on training in facilitation techniques. Crews were responsive but fell short of actively leading their own debriefings. Ways to improve debriefing effectiveness are suggested.

  18. Evaluation of Analysis Techniques for Fluted-Core Sandwich Cylinders

    NASA Technical Reports Server (NTRS)

    Lovejoy, Andrew E.; Schultz, Marc R.

    2012-01-01

    Buckling-critical launch-vehicle structures require structural concepts that have high bending stiffness and low mass. Fluted-core, also known as truss-core, sandwich construction is one such concept. In an effort to identify an analysis method appropriate for the preliminary design of fluted-core cylinders, the current paper presents and compares results from several analysis techniques applied to a specific composite fluted-core test article. The analysis techniques are evaluated in terms of their ease of use and for their appropriateness at certain stages throughout a design analysis cycle (DAC). Current analysis techniques that provide accurate determination of the global buckling load are not readily applicable early in the DAC, such as during preliminary design, because they are too costly to run. An analytical approach that neglects transverse-shear deformation is easily applied during preliminary design, but the lack of transverse-shear deformation results in global buckling load predictions that are significantly higher than those from more detailed analysis methods. The current state of the art is either too complex to be applied for preliminary design, or is incapable of the accuracy required to determine global buckling loads for fluted-core cylinders. Therefore, it is necessary to develop an analytical method for calculating global buckling loads of fluted-core cylinders that includes transverse-shear deformations, and that can be easily incorporated in preliminary design.

  19. Chromosome aberration analysis in persons exposed to low-level radiation from the JCO criticality accident in Tokai-mura.

    PubMed

    Sasaki, M S; Hayata, I; Kamada, N; Kodama, Y; Kodama, S

    2001-09-01

    Chromosome aberrations were studied in peripheral blood lymphocytes of 43 persons who were exposed to low-level radiation of mixed neutrons and gamma-rays resulting from the JCO criticality accident. When the age-adjusted frequencies of dicentric and ring chromosomes were compared with the dose calibration curve established in vitro for 60Co gamma-rays as a reference radiation, a significant correlation was observed between the chromosomally estimated doses and the documented doses evaluated by physical means. The regression coefficient of the chromosomal doses against the documented doses, 1.47 +/- 0.33, indicates that the relative biological effectiveness of fission neutrons at low doses is considerably higher than that currently adopted in the radiation protection standard.

  20. Fabrication and microstructural analysis of UN-U3Si2 composites for accident tolerant fuel applications

    NASA Astrophysics Data System (ADS)

    Johnson, Kyle D.; Raftery, Alicia M.; Lopes, Denise Adorno; Wallenius, Janne

    2016-08-01

    In this study, U3Si2 was synthesized via the use of arc-melting and mixed with UN powders, which together were sintered using the SPS method. The study revealed a number of interesting conclusions regarding the stability of the system - namely the formation of a probable but as yet unidentified ternary phase coupled with the reduction of the stoichiometry in the nitride phase - as well as some insights into the mechanics of the sintering process itself. By milling the silicide powders and reducing its particle size ratio compared to UN, it was possible to form a high density UN-U3Si2 composite, with desirable microstructural characteristics for accident tolerant fuel applications.