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Sample records for reentry risk analysis

  1. Reentry analysis

    International Nuclear Information System (INIS)

    Biehl, F.A.

    1984-05-01

    This paper presents the criteria, previous nuclear experience in space, analysis techniques, and possible breakup enhancement devices applicable to an acceptable SP-100 reentry from space. Reactor operation in nuclear-safe orbit will minimize the radiological risk; the remaining safeguards criteria need to be defined. A simple analytical point mass reentry technique and a more comprehensive analysis method that considers vehicle dynamics and orbit insertion malfunctions are presented. Vehicle trajectory, attitude, and possible breakup enhancement devices will be integrated in the simulation as required to ensure an adequate representation of the reentry process

  2. Comparison of ORSAT and SCARAB Reentry Analysis Tools for a Generic Satellite Test Case

    Science.gov (United States)

    Kelley, Robert L.; Hill, Nicole M.; Rochelle, W. C.; Johnson, Nicholas L.; Lips, T.

    2010-01-01

    Reentry analysis is essential to understanding the consequences of the full life cycle of a spacecraft. Since reentry is a key factor in spacecraft development, NASA and ESA have separately developed tools to assess the survivability of objects during reentry. Criteria such as debris casualty area and impact energy are particularly important to understanding the risks posed to people on Earth. Therefore, NASA and ESA have undertaken a series of comparison studies of their respective reentry codes for verification and improvements in accuracy. The NASA Object Reentry Survival Analysis Tool (ORSAT) and the ESA Spacecraft Atmospheric Reentry and Aerothermal Breakup (SCARAB) reentry analysis tools serve as standard codes for reentry survivability assessment of satellites. These programs predict whether an object will demise during reentry and calculate the debris casualty area of objects determined to survive, establishing the reentry risk posed to the Earth's population by surviving debris. A series of test cases have been studied for comparison and the most recent uses "Testsat," a conceptual satellite composed of generic parts, defined to use numerous simple shapes and various materials for a better comparison of the predictions of these two codes. This study is an improvement on the others in this series because of increased consistency in modeling techniques and variables. The overall comparison demonstrated that the two codes arrive at similar results. Either most objects modeled resulted in close agreement between the two codes, or if the difference was significant, the variance could be explained as a case of semantics in the model definitions. This paper presents the main results of ORSAT and SCARAB for the Testsat case and discusses the sources of any discovered differences. Discussion of the results of previous comparisons is made for a summary of differences between the codes and lessons learned from this series of tests.

  3. Simulation for Prediction of Entry Article Demise (SPEAD): An Analysis Tool for Spacecraft Safety Analysis and Ascent/Reentry Risk Assessment

    Science.gov (United States)

    Ling, Lisa

    2014-01-01

    For the purpose of performing safety analysis and risk assessment for a potential off-nominal atmospheric reentry resulting in vehicle breakup, a synthesis of trajectory propagation coupled with thermal analysis and the evaluation of node failure is required to predict the sequence of events, the timeline, and the progressive demise of spacecraft components. To provide this capability, the Simulation for Prediction of Entry Article Demise (SPEAD) analysis tool was developed. The software and methodology have been validated against actual flights, telemetry data, and validated software, and safety/risk analyses were performed for various programs using SPEAD. This report discusses the capabilities, modeling, validation, and application of the SPEAD analysis tool.

  4. ELECTRA © Launch and Re-Entry Safety Analysis Tool

    Science.gov (United States)

    Lazare, B.; Arnal, M. H.; Aussilhou, C.; Blazquez, A.; Chemama, F.

    2010-09-01

    French Space Operation Act gives as prime objective to National Technical Regulations to protect people, properties, public health and environment. In this frame, an independent technical assessment of French space operation is delegated to CNES. To perform this task and also for his owns operations CNES needs efficient state-of-the-art tools for evaluating risks. The development of the ELECTRA© tool, undertaken in 2007, meets the requirement for precise quantification of the risks involved in launching and re-entry of spacecraft. The ELECTRA© project draws on the proven expertise of CNES technical centers in the field of flight analysis and safety, spaceflight dynamics and the design of spacecraft. The ELECTRA© tool was specifically designed to evaluate the risks involved in the re-entry and return to Earth of all or part of a spacecraft. It will also be used for locating and visualizing nominal or accidental re-entry zones while comparing them with suitable geographic data such as population density, urban areas, and shipping lines, among others. The method chosen for ELECTRA© consists of two main steps: calculating the possible reentry trajectories for each fragment after the spacecraft breaks up; calculating the risks while taking into account the energy of the fragments, the population density and protection afforded by buildings. For launch operations and active re-entry, the risk calculation will be weighted by the probability of instantaneous failure of the spacecraft and integrated for the whole trajectory. ELECTRA©’s development is today at the end of the validation phase, last step before delivery to users. Validation process has been performed in different ways: numerical application way for the risk formulation; benchmarking process for casualty area, level of energy of the fragments entries and level of protection housing module; best practices in space transportation industries concerning dependability evaluation; benchmarking process for

  5. A Study on Re-entry Predictions of Uncontrolled Space Objects for Space Situational Awareness

    Science.gov (United States)

    Choi, Eun-Jung; Cho, Sungki; Lee, Deok-Jin; Kim, Siwoo; Jo, Jung Hyun

    2017-12-01

    The key risk analysis technologies for the re-entry of space objects into Earth’s atmosphere are divided into four categories: cataloguing and databases of the re-entry of space objects, lifetime and re-entry trajectory predictions, break-up models after re-entry and multiple debris distribution predictions, and ground impact probability models. In this study, we focused on re- entry prediction, including orbital lifetime assessments, for space situational awareness systems. Re-entry predictions are very difficult and are affected by various sources of uncertainty. In particular, during uncontrolled re-entry, large spacecraft may break into several pieces of debris, and the surviving fragments can be a significant hazard for persons and properties on the ground. In recent years, specific methods and procedures have been developed to provide clear information for predicting and analyzing the re-entry of space objects and for ground-risk assessments. Representative tools include object reentry survival analysis tool (ORSAT) and debris assessment software (DAS) developed by National Aeronautics and Space Administration (NASA), spacecraft atmospheric re-entry and aerothermal break-up (SCARAB) and debris risk assessment and mitigation analysis (DRAMA) developed by European Space Agency (ESA), and semi-analytic tool for end of life analysis (STELA) developed by Centre National d’Etudes Spatiales (CNES). In this study, various surveys of existing re-entry space objects are reviewed, and an efficient re-entry prediction technique is suggested based on STELA, the life-cycle analysis tool for satellites, and DRAMA, a re-entry analysis tool. To verify the proposed method, the re-entry of the Tiangong-1 Space Lab, which is expected to re-enter Earth’s atmosphere shortly, was simulated. Eventually, these results will provide a basis for space situational awareness risk analyses of the re-entry of space objects.

  6. Risk Assessment During the Final Phase of an Uncontrolled Re-Entry

    Science.gov (United States)

    Gaudel, A.; Hourtolle, C.; Goester, J. F.; Fuentes, N.

    2013-09-01

    As French National Space Agency, CNES is empowered to monitor compliance with technical regulations of the French Space Operation Act, FSOA, and to take all necessary measures to ensure the safety of people, property, public health and environment for all space operations involving French responsibility at international level.Therefore, CNES developed ELECTRA that calculates the risk for ground population involved in three types of events: rocket launching, controlled re-entry and uncontrolled re-entry. For the first two cases, ELECTRA takes into account degraded cases due to a premature stop of propulsion.Major evolutions were implemented recently on ELECTRA to meet new users' requirements, like the risk assessment during the final phase of uncontrolled re-entry, that can be combined with the computed risk for each country involved by impacts.The purpose of this paper is to provide an overview of the ELECTRA method and main functionalities, and then to highlight these recent improvements.

  7. Simulation of the ATV Re-Entry Obsrvations

    Science.gov (United States)

    Bastida Virgili, B.; Krag, H.; Lips, T.; De Pasquale, E.

    2010-09-01

    The first ATV was launched on 9th March 2008 and, after a successful mission, the last phase was a controlled destructive re-entry on 29th September 2008, shortly after 13:30 UTC, in which the remains of the ATV and its load fell into the South Pacific Ocean. In order to better understand the re-entry processes, an insitu optical observation campaign was launched to record and analyze the ATV controlled re-entry with several instruments on board of two airplanes and also from the ISS. This observation campaign was successful and triggered several different still-ongoing studies on the extraction and analysis of data to draw conclusions on the adequacy of the re-entry break-up and explosion models used for the safety analysis of the ATV re-entry. This paper addresses the validation process for ESA’s model for re-entry survivability and on-ground risk assessment for explosive re-entry events using the observation data. The underlying rationale is to improve the models for the benefit of planning and execution of future controlled re-entries and in risk calculation in case of uncontrolled ones. The re-entry trajectory of the ATV, the explosive event and the trajectories of the fragments are simulated with the existing ESA tools and the EVOLVE explosion model. Additional software has been developed to simulate airborne sensor field of view(FOV) crossings based on the aircraft trajectories, attitude profile, sensor mounts and FOVs. Sensor performance and object radiation are modeled in order to generate synthetic images for the different sensors in the ISS and the two airplanes. These synthetic images and synthetic videos are compared with the available reentry observations of the ATV. This paper will present the software and techniques to generate synthetic imagery. It will give results of the comparison between the simulated and the real trajectories and fragmentation and explain the subsequent validation process of the ESA re-entry tools and the potential

  8. Safe Reentry for False Aneurysm Operations in High-Risk Patients.

    Science.gov (United States)

    Martinelli, Gian Luca; Cotroneo, Attilio; Caimmi, Philippe Primo; Musica, Gabriele; Barillà, David; Stelian, Edmond; Romano, Angelo; Novelli, Eugenio; Renzi, Luca; Diena, Marco

    2017-06-01

    In the absence of a standardized safe surgical reentry strategy for high-risk patients with large or anterior postoperative aortic false aneurysm (PAFA), we aimed to describe an effective and safe approach for such patients. We prospectively analyzed patients treated for PAFA between 2006 and 2015. According to the preoperative computed tomography scan examination, patients were divided into two groups according to the anatomy and extension of PAFA: in group A, high-risk PAFA (diameter ≥3 cm) developed in the anterior mediastinum; in group B, low-risk PAFA (diameter <3 cm) was situated posteriorly. For group A, a safe surgical strategy, including continuous cerebral, visceral, and coronary perfusion was adopted before resternotomy; group B patients underwent conventional surgery. We treated 27 patients (safe reentry, n = 13; standard approach, n = 14). Mean age was 60 years (range, 29 to 80); 17 patients were male. Mean interval between the first operation and the last procedure was 4.3 years. Overall 30-day mortality rate was 7.4% (1 patient in each group). No aorta-related mortality was observed at 1 and 5 years in either group. The Kaplan-Meier overall survival estimates at 1 and 5 years were, respectively, 92.3% ± 7.4% and 73.4% ± 13.4% in group A, and 92.9% ± 6.9% and 72.2% ± 13.9% in group B (log rank test, p = 0.830). Freedom from reoperation for recurrent aortic disease was 100% at 1 year and 88% at 5 years. The safe reentry technique with continuous cerebral, visceral, and coronary perfusion for high-risk patients resulted in early and midterm outcomes similar to those observed for low-risk patients undergoing conventional surgery. Copyright © 2017 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.

  9. The efficacy of family reunification practices: reentry rates and correlates of reentry for abused and neglected children reunited with their families.

    Science.gov (United States)

    Terling, T

    1999-12-01

    Since the 1980s Child Protective Services has increasingly relied on family reunification for abused/neglected children rather than long term foster care or adoption. While family reunification practices are controversial, little research is available to inform the debate. This research explores the efficacy of these practices. This study utilizes two CPS data sources and both quantitative and qualitative methodologies to identify reentry rates and correlates of reentry for abused and neglected children returned to their families by CPS. System reentry due to additional maltreatment is considerable. Thirty-seven percent of the children reunited with their families reenter the system within 3 1/2 years. Correlates of reentry are identified as; abuse type, CPS history, parental competency, race, criminal history, substance abuse, and social support. Notably, assessments of risk made by caseworkers are found to be unrelated to reentry. The high reentry rate and the limitations of current risk assessment procedures suggest that CPS family reunification practices have not been entirely successful. The identification of specific risks of reentry, such as those revealed in this study, will be helpful in assessing risk on cases. In addition, future studies should explore the systemic deficiencies that contribute to the additional maltreatment that occurs for a sizable proportion of the children served by the system.

  10. Reentry safety for the Topaz II Space Reactor: Issues and analyses

    International Nuclear Information System (INIS)

    Connell, L.W.; Trost, L.C.

    1994-03-01

    This report documents the reentry safety analyses conducted for the TOPAZ II Nuclear Electric Propulsion Space Test Program (NEPSTP). Scoping calculations were performed on the reentry aerothermal breakup and ground footprint of reactor core debris. The calculations were used to assess the risks associated with radiologically cold reentry accidents and to determine if constraints should be placed on the core configuration for such accidents. Three risk factors were considered: inadvertent criticality upon reentry impact, atmospheric dispersal of U-235 fuel, and the Special Nuclear Material Safeguards risks. Results indicate that the risks associated with cold reentry are very low regardless of the core configuration. Core configuration constraints were therefore not established for radiologically cold reentry accidents

  11. DEBRISK, a Tool for Re-Entry Risk Analysis

    Science.gov (United States)

    Omaly, P.; Spel, M.

    2012-01-01

    An act of French parliament, adopted in 2008, imposes satellite constructors to evaluate the end-of-life operations in order to assure the risk mitigation of their satellites. One important element in this evaluation is the estimation of the mass and impact energy of the satellite debris after atmospheric re-entry. For this purpose, CNES has developed the tool DEBRISK which allows the operator to simulate the re-entry phase and to study the demise altitudes or impact energy of the individual fragments of the original satellite. DEBRISK is based on the so called object based approach. Using this approach, a breakup altitude is assumed where the satellite disintegrates due to the pressure loads. This altitude is typically around 78 km. After breakup, the satellite structure is modelled by a parent-child approach, where each child has its birth criterion. In the simplest approach the child is born after demise of the parent object. This could be the case of an object A containing an object B which is in the interior of object A and thus not exposed to the atmosphere. Each object is defined by: - its shape, attitude and dimensions, - the material along with their physical properties - the state and velocity vectors. The shape, attitude and dimensions define the aerodynamic drag of the object which is input to the 3DOF trajectory modelling. The aerodynamic mass used in the equation of motion is defined as the sum of the object's own mass and the mass of the object's offspring. A new born object inherits the state vector of the parent object. The shape, attitude and dimensions also define the heating rates experienced by the object. The heating rate is integrated in time up to the point where the melting temperature is reached. The mass of melted material is computed from the excess heat and the material properties. After each step the amount of ablated material is determined using the lumped mass approach and is peeled off from the object, updating mass and shape of the

  12. 'What on earth can this possibly mean'? French reentry courts and experts' risk assessment.

    Science.gov (United States)

    Herzog-Evans, Martine

    2016-01-01

    Against the backdrop of ten years of punitive criminal justice policies, the number of cases in which risk assessments by psychiatrist experts are mandatory has considerably increased in France. Because of complex and deeply ingrained cultural factors, most experts and academics oppose the use of actuarial or other structured judgement tools, which they assimilate to these policy changes. Parallel to this, the reentry judges in charge of making release and other community sentence decisions have maintained a strong rehabilitative and desistance-focused culture. Drawing on interviews with these judges and experts, the author wanted to assess the judges' expectations of experts' reports, their opinion on actuarial tools, and how they perceived experts and their aptitude to assess risk. The study showed that French reentry judges manage to keep experts' conclusions at bay when they do not fit with their desistance goals, as they can draw upon their own expertise and that of probation services. They do not have much faith in the professionalism and methodology of experts, and would like them to better demonstrate how they reach their conclusions. Moreover, criminogenic needs assessment would be much more useful to them than static risk assessment, which raises the issue as to why this is not the French probation services' role. Reentry judges who never encountered a report which uses a structured tool are influenced by the French ideological debate; those who have read such reports are unanimously in favour of such tools. It thus seems clear that they would like experts to be more strongly guided by science, but are not yet fully aware of what this entails. Copyright © 2015 Elsevier Ltd. All rights reserved.

  13. Parachute systems for the atmospheric reentry of launcher upper stages

    Directory of Open Access Journals (Sweden)

    Bogdan DOBRESCU

    2017-03-01

    Full Text Available Parachute systems can be used to control the reentry trajectory of launcher upper stages, in order to lower the risks to the population or facilitate the retrieval of the stage. Several types of parachutes deployed at subsonic, supersonic and hypersonic speeds are analyzed, modeled as single and multistage systems. The performance of deceleration parachutes depends on their drag area and deployment conditions, while gliding parachutes are configured to achieve stable flight with a high glide ratio. Gliding parachutes can be autonomously guided to a low risk landing area. Sizing the canopy is shown to be an effective method to reduce parachute sensitivity to wind. The reentry trajectory of a launcher upper stage is simulated for each parachute system configuration and the results are compared to the nominal reentry case.

  14. Analysis of Radio Frequency Blackout for a Blunt-Body Capsule in Atmospheric Reentry Missions

    Directory of Open Access Journals (Sweden)

    Yusuke Takahashi

    2016-01-01

    Full Text Available A numerical analysis of electromagnetic waves around the atmospheric reentry demonstrator (ARD of the European Space Agency (ESA in an atmospheric reentry mission was conducted. During the ARD mission, which involves a 70% scaled-down configuration capsule of the Apollo command module, radio frequency blackout and strong plasma attenuation of radio waves in communications with data relay satellites and air planes were observed. The electromagnetic interference was caused by highly dense plasma derived from a strong shock wave generated in front of the capsule because of orbital speed during reentry. In this study, the physical properties of the plasma flow in the shock layer and wake region of the ESA ARD were obtained using a computational fluid dynamics technique. Then, electromagnetic waves were expressed using a frequency-dependent finite-difference time-domain method using the plasma properties. The analysis model was validated based on experimental flight data. A comparison of the measured and predicted results showed good agreement. The distribution of charged particles around the ESA ARD and the complicated behavior of electromagnetic waves, with attenuation and reflection, are clarified in detail. It is suggested that the analysis model could be an effective tool for investigating radio frequency blackout and plasma attenuation in radio wave communication.

  15. Evaluating and Addressing Potential Hazards of Fuel Tanks Surviving Atmospheric Reentry

    Science.gov (United States)

    Kelley, Robert L.; Johnson, Nicholas L.

    2011-01-01

    In order to ensure reentering spacecraft do not pose an undue risk to the Earth's population it is important to design satellites and rocket bodies with end of life considerations in mind. In addition to considering the possible consequences of deorbiting a vehicle, consideration must also be given to the possible risks associated with a vehicle failing to become operational or reach its intended orbit. Based on recovered space debris and numerous reentry survivability analyses, fuel tanks are of particular concern in both of these considerations. Most spacecraft utilize some type of fuel tank as part of their propulsion system. These fuel tanks are most often constructed using stainless steel or titanium and are filled with potentially hazardous substances such as hydrazine and nitrogen tetroxide. For a vehicle which has reached its scheduled end of mission the contents of the tanks are typically depleted. In this scenario the use of stainless steel and titanium results in the tanks posing a risk to people and property do to the high melting point and large heat of ablation of these materials leading to likely survival of the tank during reentry. If a large portion of the fuel is not depleted prior to reentry, there is the added risk of hazardous substance being released when the tank impact the ground. This paper presents a discussion of proactive methods which have been utilized by NASA satellite projects to address the risks associated with fuel tanks reentering the atmosphere. In particular it will address the design of a demiseable fuel tank as well as the evaluation of off the shelf designs which are selected to burst during reentry.

  16. Reentry Tachycardia in Children: Adenosine Can Make It Worse.

    Science.gov (United States)

    Hien, Maximilian D; Benito Castro, Fernando; Fournier, Philippe; Filleron, Anne; Tran, Tu-Anh

    2016-10-08

    We report on a rare but severe complication of adenosine use in a child with reentry tachycardia. Treatment with adenosine, which is the standard medical therapy of atrioventricular reentry tachycardia, led to the development of an irregular wide complex tachycardia, caused by rapid ventricular response to atrial fibrillation. The girl was finally stabilized with electrical cardioversion. We analyze the pathomechanism and discuss possible treatment options. Atrial fibrillation, as well as its conduction to the ventricles, can be caused by adenosine. Rapid ventricular response in children with Wolff-Parkinson-White syndrome is more frequent than previously believed. A patient history of atrial fibrillation is a contraindication for cardioversion with adenosine and needs to be assessed in children with reentry tachycardia. High-risk patients may potentially profit from prophylactic comedication with antiarrhythmic agents, such as flecainide, ibutilide, or vernakalant, before adenosine administration.

  17. Who Comes Back? A Longitudinal Analysis of the Reentry Behavior of Exiting Teachers

    Science.gov (United States)

    Grissom, Jason A.; Reininger, Michelle

    2012-01-01

    While a large literature examines the factors that lead teachers to leave teaching, few studies have examined what factors affect teachers' decisions to reenter the profession. Drawing on research on the role of family characteristics in predicting teacher work behavior, we examine predictors of reentry. We employ survival analysis of time to…

  18. Optimal Earth's reentry disposal of the Galileo constellation

    Science.gov (United States)

    Armellin, Roberto; San-Juan, Juan F.

    2018-02-01

    Nowadays there is international consensus that space activities must be managed to minimize debris generation and risk. The paper presents a method for the end-of-life (EoL) disposal of spacecraft in Medium Earth Orbit (MEO). The problem is formulated as a multiobjective optimisation one, which is solved with an evolutionary algorithm. An impulsive manoeuvre is optimised to reenter the spacecraft in Earth's atmosphere within 100 years. Pareto optimal solutions are obtained using the manoeuvre Δv and the time-to-reentry as objective functions to be minimised. To explore at the best the search space a semi-analytical orbit propagator, which can propagate an orbit for 100 years in few seconds, is adopted. An in-depth analysis of the results is carried out to understand the conditions leading to a fast reentry with minimum propellant. For this aim a new way of representing the disposal solutions is introduced. With a single 2D plot we are able to fully describe the time evolution of all the relevant orbital parameters as well as identify the conditions that enables the eccentricity build-up. The EoL disposal of the Galileo constellation is used as test case.

  19. Correctional Practitioners on Reentry: A Missed Perspective

    Directory of Open Access Journals (Sweden)

    Elaine Gunnison

    2015-06-01

    Full Text Available Much of the literature on reentry of formerly incarcerated individuals revolves around discussions of failures they incur during reintegration or the identification of needs and challenges that they have during reentry from the perspective of community corrections officers. The present research fills a gap in the reentry literature by examining the needs and challenges of formerly incarcerated individuals and what makes for reentry success from the perspective of correctional practitioners (i.e., wardens and non-wardens. The views of correctional practitioners are important to understand the level of organizational commitment to reentry and the ways in which social distance between correctional professionals and their clients may impact reentry success. This research reports on the results from an email survey distributed to a national sample of correctional officials listed in the American Correctional Association, 2012 Directory. Specifically, correctional officials were asked to report on needs and challenges facing formerly incarcerated individuals, define success, identify factors related to successful reentry, recount success stories, and report what could be done to assist them in successful outcomes. Housing and employment were raised by wardens and corrections officials as important needs for successful reentry. Corrections officials adopted organizational and systems perspectives in their responses and had differing opinions about social distance. Policy implications are presented.

  20. Social Support, Motivation, and the Process of Juvenile Reentry: An Exploratory Analysis of Desistance

    Science.gov (United States)

    Panuccio, Elizabeth A.; Christian, Johnna; Martinez, Damian J.; Sullivan, Mercer L.

    2012-01-01

    Many scholarly works and studies have explored the experience of reentry and desistance for adult offenders, but fewer studies have focused on these processes among juvenile offenders. Using qualitative case studies of juveniles released from secure confinement, this study explores the desistance process during juvenile reentry by examining how…

  1. Potential Dermal Exposure in greenhouses for manual sprayers: Analysis of the mix/load, application and re-entry stages

    Energy Technology Data Exchange (ETDEWEB)

    Ramos, Laura M.; Querejeta, Giselle A.; Flores, Andrea P.; Hughes, Enrique A.; Zalts, Anita [Instituto de Ciencias, Universidad Nacional de General Sarmiento (UNGS), J. M. Gutierrez 1150, (B1613GSX) Los Polvorines, Prov. de Buenos Aires (Argentina); Montserrat, Javier M., E-mail: jmontser@ungs.edu.ar [Instituto de Ciencias, Universidad Nacional de General Sarmiento (UNGS), J. M. Gutierrez 1150, (B1613GSX) Los Polvorines, Prov. de Buenos Aires (Argentina); Instituto de Investigaciones en Ingenieria Genetica y Biologia Molecular (CONICET), Vuelta de Obligado 2490, 2o piso, Buenos Aires (Argentina)

    2010-09-01

    An evaluation of the Potential Dermal Exposure for the mix/load, application and re-entry stages, associated with procymidone and deltamethrin usage, was carried out for tomatoes grown in greenhouses of small production units in Argentina. Eight experiments were done with four different operators, under typical field conditions with a lever operated backpack sprayer. The methodology applied was based on the Whole Body Dosimetry technique, evaluating a set of different data for the mix and load, application and re-entry operations. These results indicated that the Potential Dermal Exposure of the application step was (38 {+-} 17) mL h{sup -1} with the highest proportion on torso, head and arms. When the three stages were compared, re-entry was found to contribute least towards the total Potential Dermal Exposure; meanwhile in all cases, except one, the mix/load operation was the stage with highest exposure. The Margin of Safety for each different operation was also calculated and the proportion of pesticide drift from the greenhouse to the environment is presented. These results emphasize the importance of improving the personal protection measures in the mix and load stage, an operation that is not usually associated with high-risk in small production units.

  2. Potential Dermal Exposure in greenhouses for manual sprayers: Analysis of the mix/load, application and re-entry stages

    International Nuclear Information System (INIS)

    Ramos, Laura M.; Querejeta, Giselle A.; Flores, Andrea P.; Hughes, Enrique A.; Zalts, Anita; Montserrat, Javier M.

    2010-01-01

    An evaluation of the Potential Dermal Exposure for the mix/load, application and re-entry stages, associated with procymidone and deltamethrin usage, was carried out for tomatoes grown in greenhouses of small production units in Argentina. Eight experiments were done with four different operators, under typical field conditions with a lever operated backpack sprayer. The methodology applied was based on the Whole Body Dosimetry technique, evaluating a set of different data for the mix and load, application and re-entry operations. These results indicated that the Potential Dermal Exposure of the application step was (38 ± 17) mL h -1 with the highest proportion on torso, head and arms. When the three stages were compared, re-entry was found to contribute least towards the total Potential Dermal Exposure; meanwhile in all cases, except one, the mix/load operation was the stage with highest exposure. The Margin of Safety for each different operation was also calculated and the proportion of pesticide drift from the greenhouse to the environment is presented. These results emphasize the importance of improving the personal protection measures in the mix and load stage, an operation that is not usually associated with high-risk in small production units.

  3. The reentry catheter: a second chance for endoluminal reentry at difficult lower extremity subintimal arterial recanalizations.

    Science.gov (United States)

    Etezadi, Vahid; Benenati, James F; Patel, Parag J; Patel, Rahul S; Powell, Alex; Katzen, Barry T

    2010-05-01

    From January 2005 to July 2008, a retrospective study was conducted at a single institution to investigate technical success of the use of a reentry device (Outback LTD reentry catheter) in aortoiliac and femoropopliteal artery recanalization in 34 patients (18 men; mean age +/- SD, 72 years +/- 11) in whom the conventional guide wires and catheters failed to reenter the true lumen. True lumen reentry was achieved in 87% (n = 23) and 91% (n = 11) of patients with femoropopliteal and aortoiliac occlusions, respectively. The overall technical success rate with the device was 88% (n = 34). The device success rate in Transatlantic Inter-Society Consensus II class D lesions was significantly lower than in lower lesion classes (71.4% vs 100%; P < .05). No procedure-related complications were encountered. In conclusion, the use of the reentry catheter enhances the likelihood of successful subintimal recanalization of chronic occlusions in femoropopliteal and aortoiliac arteries.

  4. Surface dust criteria for dioxin and dioxin-like compounds for re-entry to buildings

    Energy Technology Data Exchange (ETDEWEB)

    Greene, J.; Brorby, G.; Warmerdam, J. [Exponent, Oakland, CA (United States); Paustenbach, D. [ChemRisk, San Francisco, CA (United States)

    2004-09-15

    Introduction. Building reentry criteria for dioxin TEQ, as measured by surface wipes, vary greatly, from as low as 1 ng/m{sup 2} to as high as 125 ng/m{sup 2}1. Recently, the World Trade Center Indoor Air Taskforce calculated a reentry criterion of 2 ng TEQ/m{sup 2} for a residential exposure. This number was based on the EPA's draft cancer slope factor (CSF) of 1 x 10{sup 6} (mg/kg-day)-1, and various exposure parameters, dermal absorption values, and a cancer risk criterion of 1 x 10{sup -4}. An indoor 'degradation' parameter was also included in the calculations. However, a single criterion based on a single set of assumptions cannot be universally applied to all sites with contaminated surfaces. Reentry criteria that consider a wider range of exposure scenarios, exposure pathways, bioavailability, and behavioral parameters would be very useful to risk managers who may have to address multiple diverse situations in the coming years. This paper describes our recommended reentry ''building surface'' criteria for four exposure scenarios: (1) adult occupational, (2) adult residential, (3) childhood ''occupational'' (i.e., school), and (4) childhood residential.

  5. Can Social Capital Networks Assist Re-entry Felons to Overcome Barriers to Re-entry and Reduce Recidivism?

    Directory of Open Access Journals (Sweden)

    Earl Smith

    2011-05-01

    Full Text Available Based on interviews with 25 reentry felons, this article examines the impact that social capital plays in successful reentry; specifically with securing stable housing and employment. We found that access to social capital allowed those with the lowest probability for success—African American men with felony convictions—to secure both stable employment and housing and thus avoid engaging in illegitimate behavior that leads to recidivism. The findings suggest that even for those individuals reentering society with the most strikes against them (as noted by researchers such as Pager and Travis, access to the resource rich social capital networks provided by reentry programs can allow these individuals to overcome the barriers to reentry and find stable jobs and secure housing. Our findings suggest that more research be done on the impact of social capital embedded in reentry programs and that referrals be made to these types of programs and funding be provided for those that demonstrate the ability to significantly reduce recidivism. As Putman has noted, "Just as a screwdriver (physical capital or a college education (human capital can increase productivity (both individual and collective, so do social contacts affect the productivity of individuals and groups."

  6. Project, Aerodynamic, Thermal and Ballistic Analysis of a Lifting-Body Reentry Vehicle

    Directory of Open Access Journals (Sweden)

    A. N. Eliseev

    2015-01-01

    Full Text Available The objective of this article is to assess the prospects for an increasingly maneuverable reentry vehicle (RV of class "lifting body". In this regard, a project aerodynamic thermal and ballistic analysis has been conducted and the results have been compared with some well-known projects of the RV of the same class, made both in our country and abroad.The project analysis begins with finding a position of the "lifting body" vehicle in the classification system. Said classification distribution allows correct formulation of requirements for the conceptual structure of an aerospace vehicle at the initial stage of design in terms of system positions, since just the initial phase of the design often determines the success of the whole program.Then the paper compares design characteristics of the RV of class "lifting body" with vehicles such as X-15 rocket plane, the orbiter "Space Shuttle», M2-F2, HL-10, SV-5, and NASP "Hermes". It also gives a comparative estimate of the "lifting body" RV mass in a wide range of dimensions. The paper shows the sustainability of various landing complexes with reference to the Russian experience in developing the RV " Soyuz", and the conditions for using the vehicles of class "lifting body" in space programs.The aerodynamic analysis uses method for the approximate Newtonian theory to calculate aerodynamic characteristics of the perspective RV of class "lifting body" in the hypersonic descent phase. To obtain the desired aerodynamic performance and reduce balancing weight is contemplated a possibility to provide balance by introducing additional boards. The ballistic analysis considers four modes of descent:1. zero roll descent;2. maximum cross-range descent without restriction;3. maximum cross-range descent with restriction of maximum overload and maximum temperature;4. ballistic descent.To calculate the RV ballistic characteristics a system of equations of the vehicle motion in the atmosphere is used. The vehicle

  7. 75 FR 75621 - Office of Commercial Space Transportation; Waiver of Autonomous Reentry Restriction for a Reentry...

    Science.gov (United States)

    2010-12-06

    ... Dragon's reentry to Earth is in the public interest and will not jeopardize public health and safety... proposes that the FAA permit the autonomous reentry of a healthy Dragon at the nominal landing location in...; (2) the vehicle has the ability to autonomously guide itself to the same pre-determined landing site...

  8. Reentry challenges facing women with mental health problems.

    Science.gov (United States)

    Visher, Christy A; Bakken, Nicholas W

    2014-01-01

    Women entering the correctional system represent a population at high risk for mental health and the body of research on the mental health needs of women offenders is growing. These mental health problems pose challenges for women at every stage of the criminal justice process, from arrest to incarceration to community reentry and reintegration. In this article, we examined mental health status among a sample of 142 women leaving confinement and the role that mental health problems played in shaping their reentry outcomes using data collected between 2002 and 2005 in Houston, Texas. In the year after leaving prison, women with mental health problems reported poorer health, more hospitalizations, more suicidal thoughts, greater difficulties securing housing and employment, more involvement in criminal behavior, and less financial support from family than women with no indication of mental health problems. However, mental health status did not increase the likelihood of substance use relapse or reincarceration. The article concludes with a discussion of recommendations for improved policy and practice.

  9. NPSAT1: Assessment Of Risk For Human Casualty From Atmospheric Reentry

    Science.gov (United States)

    2016-03-01

    wrapped copper wire, resembling a large solenoid. Between their core and insulations , these wires are approximately 0.370 millimeter in diameter and... insulation is melted. This action would expose the wires to significantly greater stress during atmospheric reentry and would most likely end in their...solid piece of metal to create a hollow void for cables when assembled. Modeling this component requires the operator to reduce the overall structure to

  10. Research on the Frequency Aliasing of Resistance Acceleration Guidance for Reentry Flight

    Directory of Open Access Journals (Sweden)

    Han Pengxin

    2017-01-01

    Full Text Available According to the special response of resistance acceleration during hypersonic reentry flight, different guidance frequency will result to very different flight and control response. The analysis model for the response of resistance acceleration to the attack angle and dynamic press is put forward respectively in this paper. And the frequency aliasing phenomenon of guidance is revealed. The simulation results to the same vehicle sufficiently substantiate the frequency aliasing of resistance acceleration during reentry guidance.

  11. Reentry response of the lightweight radioisotope heater unit resulting from a Cassini Venus-Venus-Earth-Jupiter gravity assist maneuver accident

    International Nuclear Information System (INIS)

    1996-12-01

    Reentry analyses consisting of ablation response, thermal response and thermal stress response have been conducted on the Lightweight Radioisotope Heater Unit (LWRHU) for Cassini/Venus-Venus-Earth-Jupiter-Gravity-Assist (VVEJGA) reentry conditions. Sequential ablation analyses of the LWRHU aeroshell, and the fuel pellet have been conducted in reentry regimes where the aeroshell has been deemed to fail. The failure criterion for ablation is generally assumed to be recession corresponding to 75% and 100% of the wall thickness. The 75% recession failure criteria allows for uncertainties that result mainly because of the high energies involved in the VVEJGA reentries compared to orbital decay reentries. Risk evaluations should consider the fact that for shallow flight paths the unit may disassemble at high-altitude as a result of ablation or may remain intact with a clad that had been molten. Within the limitations of the methodologies and assumptions of the analyses, the results indicate that: (1) For a side-on stable LWRHU reentry, aeroshell ablation failures occur for all reentry angles. (2)For a side-on spinning LWRHU reentry, aeroshell ablation failures are minimal. (3) For the tumbling LWRHU reentry, the aeroshell survives for most angles. (4) For the thermostructural analyses, using both a 1% and 5% allowable strain, all reentry angles and orientations examined resulted in small localized failures, but aeroshell breach is not predicted for any case. The analyses included in this report concentrate on VVEJGA reentry scenarios. Analyses reported previously have demonstrated that the LWRHU has adequate design margin to survive reentry from orbital decay scenarios and most injection scenarios at speeds up to escape speeds. The exception is a narrow range of flight path angles that produce multiple skip trajectories which may have excessive ablation

  12. Development and Validation of Reentry Simulation Using MATLAB

    National Research Council Canada - National Science Library

    Jameson, Jr, Robert E

    2006-01-01

    This research effort develops a program using MATLAB to solve the equations of motion for atmospheric reentry and analyzes the validity of the program for use as a tool to expeditiously predict reentry profiles...

  13. Pico Reentry Probes: Affordable Options for Reentry Measurements and Testing

    Science.gov (United States)

    Ailor, William H.; Kapoor, Vinod B.; Allen, Gay A., Jr.; Venkatapathy, Ethiraj; Arnold, James O.; Rasky, Daniel J.

    2005-01-01

    It is generally very costly to perform in-space and atmospheric entry experiments. This paper presents a new platform - the Pico Reentry Probe (PREP) - that we believe will make targeted flight-tests and planetary atmospheric probe science missions considerably more affordable. Small, lightweight, self-contained, it is designed as a "launch and forget" system, suitable for experiments that require no ongoing communication with the ground. It contains a data recorder, battery, transmitter, and user-customized instrumentation. Data recorded during reentry or space operations is returned at end-of-mission via transmission to Iridium satellites (in the case of earth-based operations) or a similar orbiting communication system for planetary missions. This paper discusses possible applications of this concept for Earth and Martian atmospheric entry science. Two well-known heritage aerodynamic shapes are considered as candidates for PREP: the shape developed for the Planetary Atmospheric Experiment Test (PAET) and that for the Deep Space II Mars Probe.

  14. Flight Performance of the Inflatable Reentry Vehicle Experiment 3

    Science.gov (United States)

    Dillman, Robert; DiNonno, John; Bodkin, Richard; Gsell, Valerie; Miller, Nathanael; Olds, Aaron; Bruce, Walter

    2013-01-01

    The Inflatable Reentry Vehicle Experiment 3 (IRVE-3) launched July 23, 2012, from NASA Wallops Flight Facility (WFF) on a Black Brant XI suborbital sounding rocket and successfully performed its mission, demonstrating the survivability of a hypersonic inflatable aerodynamic decelerator (HIAD) in the reentry heating environment and also illustrating the effect of an offset center of gravity on the HIAD's lift-to-drag ratio. IRVE-3 was a follow-on to 2009's IRVE-II mission, which demonstrated exo-atmospheric inflation, reentry survivability - without significant heating - and the aerodynamic stability of a HIAD down to subsonic flight conditions. NASA Langley Research Center is leading the development of HIAD technology for use on future interplanetary and Earth reentry missions.

  15. Incarcerated women's relationship-based strategies to avoid drug use after community re-entry.

    Science.gov (United States)

    Snell-Rood, Claire; Staton-Tindall, Michele; Victor, Grant

    2016-10-01

    While recent research has stressed the supportive role that family and friends play for incarcerated persons as they re-enter the community, drug-using incarcerated women re-entering the community often have to rely on family, community, and intimate relationships that have played a role in their substance abuse and criminalization. In this study the authors conducted qualitative analysis of clinical sessions with rural, drug-using women (N = 20) in a larger prison-based HIV risk reduction intervention in Kentucky during 2012-2014 to examine incarcerated women's perceptions of the role of their family, community, and intimate relationships in their plans to decrease their substance abuse upon community re-entry. Women stressed the obstacles to receiving support in many of their family and drug-using relationships after community re-entry. Nonetheless, they asserted that changes in their relationships could support their desires to end their substance abuse by setting limits on and using their positive relationships, particularly with their children, to motivate them to change. Interventions to promote incarcerated women's health behavior changes-including substance abuse-must acknowledge the complex social environments in which they live.

  16. Plume-Free Stream Interaction Heating Effects During Orion Crew Module Reentry

    Science.gov (United States)

    Marichalar, J.; Lumpkin, F.; Boyles, K.

    2012-01-01

    During reentry of the Orion Crew Module (CM), vehicle attitude control will be performed by firing reaction control system (RCS) thrusters. Simulation of RCS plumes and their interaction with the oncoming flow has been difficult for the analysis community due to the large scarf angles of the RCS thrusters and the unsteady nature of the Orion capsule backshell environments. The model for the aerothermal database has thus relied on wind tunnel test data to capture the heating effects of thruster plume interactions with the freestream. These data are only valid for the continuum flow regime of the reentry trajectory. A Direct Simulation Monte Carlo (DSMC) analysis was performed to study the vehicle heating effects that result from the RCS thruster plume interaction with the oncoming freestream flow at high altitudes during Orion CM reentry. The study was performed with the DSMC Analysis Code (DAC). The inflow boundary conditions for the jets were obtained from Data Parallel Line Relaxation (DPLR) computational fluid dynamics (CFD) solutions. Simulations were performed for the roll, yaw, pitch-up and pitch-down jets at altitudes of 105 km, 125 km and 160 km as well as vacuum conditions. For comparison purposes (see Figure 1), the freestream conditions were based on previous DAC simulations performed without active RCS to populate the aerodynamic database for the Orion CM. Other inputs to the analysis included a constant Orbital reentry velocity of 7.5 km/s and angle of attack of 160 degrees. The results of the study showed that the interaction effects decrease quickly with increasing altitude. Also, jets with highly scarfed nozzles cause more severe heating compared to the nozzles with lower scarf angles. The difficulty of performing these simulations was based on the maximum number density and the ratio of number densities between the freestream and the plume for each simulation. The lowest altitude solutions required a substantial amount of computational resources

  17. In Depth Analysis of AVCOAT TPS Response to a Reentry Flow

    International Nuclear Information System (INIS)

    Titov, E. V.; Kumar, Rakesh; Levin, D. A.

    2011-01-01

    Modeling of the high altitude portion of reentry vehicle trajectories with DSMC or statistical BGK solvers requires accurate evaluation of the boundary conditions at the ablating TPS surface. Presented in this article is a model which takes into account the complex ablation physics including the production of pyrolysis gases, and chemistry at the TPS surface. Since the ablation process is time dependent the modeling of the material response to the high energy reentry flow starts with the solution of the rarefied flow over the vehicle and then loosely couples with the material response. The objective of the present work is to carry out conjugate thermal analysis by weakly coupling a flow solver to a material thermal response model. The latter model solves the one dimensional heat conduction equation accounting for the pyrolysis process that takes place in the reaction zone of an ablative thermal protection system (TPS) material. An estimate of the temperature range within which the pyrolysis reaction (decomposition and volatilization) takes place is obtained from Ref. [1]. The pyrolysis reaction results in the formation of char and the release of gases through the porous charred material. These gases remove additional amount of heat as they pass through the material, thus cooling the material (the process known as transpiration cooling). In the present work, we incorporate the transpiration cooling model in the material thermal response code in addition to the pyrolysis model. The flow in the boundary layer and in the vicinity of the TPS material is in the transitional flow regime. Therefore, we use a previously validated statistical BGK method to model the flow physics in the vicinity of the micro-cracks, since the BGK method allows simulations of flow at pressures higher than can be computed using DSMC.

  18. Displacements of Metallic Thermal Protection System Panels During Reentry

    Science.gov (United States)

    Daryabeigi, Kamran; Blosser, Max L.; Wurster, Kathryn E.

    2006-01-01

    Bowing of metallic thermal protection systems for reentry of a previously proposed single-stage-to-orbit reusable launch vehicle was studied. The outer layer of current metallic thermal protection system concepts typically consists of a honeycomb panel made of a high temperature nickel alloy. During portions of reentry when the thermal protection system is exposed to rapidly varying heating rates, a significant temperature gradient develops across the honeycomb panel thickness, resulting in bowing of the honeycomb panel. The deformations of the honeycomb panel increase the roughness of the outer mold line of the vehicle, which could possibly result in premature boundary layer transition, resulting in significantly higher downstream heating rates. The aerothermal loads and parameters for three locations on the centerline of the windward side of this vehicle were calculated using an engineering code. The transient temperature distributions through a metallic thermal protection system were obtained using 1-D finite volume thermal analysis, and the resulting displacements of the thermal protection system were calculated. The maximum deflection of the thermal protection system throughout the reentry trajectory was 6.4 mm. The maximum ratio of deflection to boundary layer thickness was 0.032. Based on previously developed distributed roughness correlations, it was concluded that these defections will not result in tripping the hypersonic boundary layer.

  19. Analysis of Electromagnetic Wave Propagation in a Magnetized Re-Entry Plasma Sheath Via the Kinetic Equation

    Science.gov (United States)

    Manning, Robert M.

    2009-01-01

    Based on a theoretical model of the propagation of electromagnetic waves through a hypersonically induced plasma, it has been demonstrated that the classical radiofrequency communications blackout that is experienced during atmospheric reentry can be mitigated through the appropriate control of an external magnetic field of nominal magnitude. The model is based on the kinetic equation treatment of Vlasov and involves an analytical solution for the electric and magnetic fields within the plasma allowing for a description of the attendant transmission, reflection and absorption coefficients. The ability to transmit through the magnetized plasma is due to the magnetic windows that are created within the plasma via the well-known whistler modes of propagation. The case of 2 GHz transmission through a re-entry plasma is considered. The coefficients are found to be highly sensitive to the prevailing electron density and will thus require a dynamic control mechanism to vary the magnetic field as the plasma evolves through the re-entry phase.

  20. Effects of Reentry Plasma Sheath on GPS Patch Antenna Polarization Property

    Directory of Open Access Journals (Sweden)

    L. Zhao

    2013-01-01

    Full Text Available A plasma sheath enveloping a reentry vehicle would affect performances of on-board antenna greatly, especially the navigation antennas. This paper studies the effects of reentry plasma sheath on a GPS right-hand circularly polarized (RHCP patch antenna polarization property during a typical reentry process. Utilizing the algorithm of finite integration technique, the polarization characteristic of a GPS antenna coated by a plasma sheath is obtained. Results show that the GPS RHCP patch antenna radiation pattern distortions as well as polarization deteriorations exist during the entire reentry process, and the worst polarization mismatch loss between a GPS antenna and RHCP GPS signal is nearly 3 dB. This paper also indicates that measures should be taken to alleviate the plasma sheath for maintaining the GPS communication during the reentry process.

  1. Demonstrator of atmospheric reentry system with hyperbolic velocity—DASH

    Science.gov (United States)

    Morita, Yasuhiro; Kawaguchi, Jun'ichiro; Inatani, Yoshifumi; Abe, Takashi

    2003-01-01

    Among a wide variety of challenging projects planned for the coming decade is the MUSES-C mission designed by the ISAS of Japan. Despite huge amount of data collected by the previous interplanetary spacecraft and probes, the origin and evolution of the solar system still remains unveiled due to their limited information. Thus, our concern has been directed toward a sample return to carry sample from an asteroid back to the earth, which will contribute to better understanding of the system. One of the keys to success is considered the reentry technology with hyperbolic velocity, which has not been demonstrated yet. With this as background, the demonstrator of atmospheric reentry system with hyperbolic velocity, DASH, has been given a commitment to demonstrate the high-speed reentry technology, which will be launched in summer of next year by Japan's H-IIA rocket in a piggyback configuration. The spaceship, composed of a reentry capsule and its carrier, will be injected into a geostationary transfer orbit (GTO) and after several revolutions it will deorbit by burn of a solid propellant deorbit motor. The capsule, identical to that of the sample return mission, can experience the targeted level of thermal environment even from the GTO by tracing a specially designed reentry trajectory.

  2. Phase 2 reentry in man

    DEFF Research Database (Denmark)

    Thomsen, P.E.B.; Jørgensen, R.M.; Kanters, J.K.

    2005-01-01

    -wave changes documented in the last sinus beat prior to ventricular extrasystoles are in agreement with phase 2 reentry, suggesting that this may be the responsible mechanism for ventricular extrasystoles and ventricular tachycardia/fibrillation. The phenomenon has been demonstrated in only animal experiments...... phase 2 reentry, demonstrated in animal experiments to initiate ventricular extrasystoles, ventricular tachycardia, and ventricular fibrillation, also plays a role in humans. METHODS We examined 18 patients with ventricular extrasystoles and/or ventricular tachycardia by signal averaging of the ECG...... patients undergoing radiofrequency ablation. Eight of the 11 patients had right ventricular outflow tract extrasystoles. RESULTS In six of the seven patients in group A, we demonstrated significant ST-elevation and/or T-wave changes in the sinus beat preceding ventricular extrasystoles compared...

  3. Application of the FADS system on the Re-entry Module

    Science.gov (United States)

    Zhen, Huang

    2016-07-01

    The aerodynamic model for Flush Air Data Sensing System (FADS) is built based on the surface pressure distribution obtained through the pressure orifices laid on specific positions of the surface,and the flight parameters,such as angle of attack,angle of side-slip,Mach number,free-stream static pressure and dynamic pressure are inferred from the aerodynamic model.The flush air data sensing system (FADS) has been used on several flight tests of aircraft and re-entry vehicle,such as,X-15,space shuttle,F-14,X-33,X-43A and so on. This paper discusses the application of the FADS on the re-entry module with blunt body to obtain high-precision aerodynamic parameters.First of all,a basic theory and operating principle of the FADS is shown.Then,the applications of the FADS on typical aircrafts and re-entry vehicles are described.Thirdly,the application mode on the re-entry module with blunt body is discussed in detail,including aerodynamic simulation,pressure distribution,trajectory reconstruction and the hardware shoule be used,such as flush air data sensing system(FADS),inertial navigation system (INS),data acquisition system,data storage system.Finally,ablunt module re-entry flight test from low earth orbit (LEO) is planned to obtain aerodynamic parameters and amend the aerodynamic model with this FADS system data.The results show that FADS system can be applied widely in re-entry module with blunt bodies.

  4. Reentry Vehicle Flight Controls Design Guidelines: Dynamic Inversion

    Science.gov (United States)

    Ito, Daigoro; Georgie, Jennifer; Valasek, John; Ward, Donald T.

    2002-01-01

    This report addresses issues in developing a flight control design for vehicles operating across a broad flight regime and with highly nonlinear physical descriptions of motion. Specifically it addresses the need for reentry vehicles that could operate through reentry from space to controlled touchdown on Earth. The latter part of controlled descent is achieved by parachute or paraglider - or by all automatic or a human-controlled landing similar to that of the Orbiter. Since this report addresses the specific needs of human-carrying (not necessarily piloted) reentry vehicles, it deals with highly nonlinear equations of motion, and then-generated control systems must be robust across a very wide range of physics. Thus, this report deals almost exclusively with some form of dynamic inversion (DI). Two vital aspects of control theory - noninteracting control laws and the transformation of nonlinear systems into equivalent linear systems - are embodied in DI. Though there is no doubt that the mathematical tools and underlying theory are widely available, there are open issues as to the practicality of using DI as the only or primary design approach for reentry articles. This report provides a set of guidelines that can be used to determine the practical usefulness of the technique.

  5. Reentry Works: The Implementation and Effectiveness of a Serious and Violent Offender Reentry Initiative

    Science.gov (United States)

    Bouffard, Jeffrey A.; Bergeron, Lindsey E.

    2006-01-01

    Spurred by large increases in prison populations and other recent sentencing and correctional trends, the federal government has supported the development and implementation of Serious and Violent Offender Reentry Initiatives (SVORI) nationwide. While existing research demonstrates the effectiveness of the separate components of these programs…

  6. An adaptive reentry guidance method considering the influence of blackout zone

    Science.gov (United States)

    Wu, Yu; Yao, Jianyao; Qu, Xiangju

    2018-01-01

    Reentry guidance has been researched as a popular topic because it is critical for a successful flight. In view that the existing guidance methods do not take into account the accumulated navigation error of Inertial Navigation System (INS) in the blackout zone, in this paper, an adaptive reentry guidance method is proposed to obtain the optimal reentry trajectory quickly with the target of minimum aerodynamic heating rate. The terminal error in position and attitude can be also reduced with the proposed method. In this method, the whole reentry guidance task is divided into two phases, i.e., the trajectory updating phase and the trajectory planning phase. In the first phase, the idea of model predictive control (MPC) is used, and the receding optimization procedure ensures the optimal trajectory in the next few seconds. In the trajectory planning phase, after the vehicle has flown out of the blackout zone, the optimal reentry trajectory is obtained by online planning to adapt to the navigation information. An effective swarm intelligence algorithm, i.e. pigeon inspired optimization (PIO) algorithm, is applied to obtain the optimal reentry trajectory in both of the two phases. Compared to the trajectory updating method, the proposed method can reduce the terminal error by about 30% considering both the position and attitude, especially, the terminal error of height has almost been eliminated. Besides, the PIO algorithm performs better than the particle swarm optimization (PSO) algorithm both in the trajectory updating phase and the trajectory planning phases.

  7. Advanced validation of CFD-FDTD combined method using highly applicable solver for reentry blackout prediction

    International Nuclear Information System (INIS)

    Takahashi, Yusuke

    2016-01-01

    An analysis model of plasma flow and electromagnetic waves around a reentry vehicle for radio frequency blackout prediction during aerodynamic heating was developed in this study. The model was validated based on experimental results from the radio attenuation measurement program. The plasma flow properties, such as electron number density, in the shock layer and wake region were obtained using a newly developed unstructured grid solver that incorporated real gas effect models and could treat thermochemically non-equilibrium flow. To predict the electromagnetic waves in plasma, a frequency-dependent finite-difference time-domain method was used. Moreover, the complicated behaviour of electromagnetic waves in the plasma layer during atmospheric reentry was clarified at several altitudes. The prediction performance of the combined model was evaluated with profiles and peak values of the electron number density in the plasma layer. In addition, to validate the models, the signal losses measured during communication with the reentry vehicle were directly compared with the predicted results. Based on the study, it was suggested that the present analysis model accurately predicts the radio frequency blackout and plasma attenuation of electromagnetic waves in plasma in communication. (paper)

  8. Childhood cancer survivors' school (re)entry: Australian parents' perceptions.

    Science.gov (United States)

    McLoone, J K; Wakefield, C E; Cohn, R J

    2013-07-01

    Starting or returning to school after intense medical treatment can be academically and socially challenging for childhood cancer survivors. This study aimed to evaluate the school (re)entry experience of children who had recently completed cancer treatment. Forty-two semi-structured telephone interviews were conducted to explore parents' perceptions of their child's (re)entry to school after completing treatment (23 mothers, 19 fathers, parent mean age 39.5 years; child mean age 7.76 years). Interviews were analysed using the framework of Miles and Huberman and emergent themes were organised using QSR NVivo8. Parents closely monitored their child's school (re)entry and fostered close relationships with their child's teacher to ensure swift communication of concerns should they arise. The most commonly reported difficulty related to aspects of peer socialisation; survivors either displayed a limited understanding of social rules such as turn taking, or related more to older children or teachers relative to their peers. Additionally, parents placed a strong emphasis on their child's overall personal development, above academic achievement alone. Improved parent, clinician and teacher awareness of the importance of continued peer socialisation during the treatment period is recommended in order to limit the ongoing ramifications this may have on school (re)entry post-treatment completion. © 2013 John Wiley & Sons Ltd.

  9. Hayabusa Re-Entry: Trajectory Analysis and Observation Mission Design

    Science.gov (United States)

    Cassell, Alan M.; Winter, Michael W.; Allen, Gary A.; Grinstead, Jay H.; Antimisiaris, Manny E.; Albers, James; Jenniskens, Peter

    2011-01-01

    On June 13th, 2010, the Hayabusa sample return capsule successfully re-entered Earth s atmosphere over the Woomera Prohibited Area in southern Australia in its quest to return fragments from the asteroid 1998 SF36 Itokawa . The sample return capsule entered at a super-orbital velocity of 12.04 km/sec (inertial), making it the second fastest human-made object to traverse the atmosphere. The NASA DC-8 airborne observatory was utilized as an instrument platform to record the luminous portion of the sample return capsule re-entry (60 sec) with a variety of on-board spectroscopic imaging instruments. The predicted sample return capsule s entry state information at 200 km altitude was propagated through the atmosphere to generate aerothermodynamic and trajectory data used for initial observation flight path design and planning. The DC- 8 flight path was designed by considering safety, optimal sample return capsule viewing geometry and aircraft capabilities in concert with key aerothermodynamic events along the predicted trajectory. Subsequent entry state vector updates provided by the Deep Space Network team at NASA s Jet Propulsion Laboratory were analyzed after the planned trajectory correction maneuvers to further refine the DC-8 observation flight path. Primary and alternate observation flight paths were generated during the mission planning phase which required coordination with Australian authorities for pre-mission approval. The final observation flight path was chosen based upon trade-offs between optimal viewing requirements, ground based observer locations (to facilitate post-flight trajectory reconstruction), predicted weather in the Woomera Prohibited Area and constraints imposed by flight path filing deadlines. To facilitate sample return capsule tracking by the instrument operators, a series of two racetrack flight path patterns were performed prior to the observation leg so the instruments could be pointed towards the region in the star background where

  10. RITD - Re-entry: Inflatable Technology Development in Russian Collaboration

    Science.gov (United States)

    Heilimo, J.; Harri, A.-M.; Aleksashkin, S.; Koryanov, V.; Arruego, I.; Schmidt, W.; Haukka, H.; Finchenko, V.; Martynov, M.; Ostresko, B.; Ponomarenko, A.; Kazakovtsev, V.; Martin, S.; Siili, T.

    2014-04-01

    A new generation of inflatable Entry, Descent and Landing System (EDLS) for Mars has been developed. It is used in both the initial atmospheric entry and atmospheric descent before the semi-hard impact of the penetrator into Martian surface. The EDLS applicability to Earth's atmosphere is studied by the EU/RITD [1] project. Project focuses on the analysis and tests of the transonic behaviour of this compact and light weight payload entry system at the Earth re-entry.

  11. Recovery, Transportation and Acceptance to the Curation Facility of the Hayabusa Re-Entry Capsule

    Science.gov (United States)

    Abe, M.; Fujimura, A.; Yano, H.; Okamoto, C.; Okada, T.; Yada, T.; Ishibashi, Y.; Shirai, K.; Nakamura, T.; Noguchi, T.; hide

    2011-01-01

    The "Hayabusa" re-entry capsule was safely carried into the clean room of Sagamihara Planetary Sample Curation Facility in JAXA on June 18, 2010. After executing computed tomographic (CT) scanning, removal of heat shield, and surface cleaning of sample container, the sample container was enclosed into the clean chamber. After opening the sample container and residual gas sampling in the clean chamber, optical observation, sample recovery, sample separation for initial analysis will be performed. This curation work is continuing for several manths with some selected member of Hayabusa Asteroidal Sample Preliminary Examination Team (HASPET). We report here on the 'Hayabusa' capsule recovery operation, and transportation and acceptance at the curation facility of the Hayabusa re-entry capsule.

  12. IXV re-entry demonstrator: Mission overview, system challenges and flight reward

    Science.gov (United States)

    Angelini, Roberto; Denaro, Angelo

    2016-07-01

    The Intermediate eXperimental Vehicle (IXV) is an advanced re-entry demonstrator vehicle aimed to perform in-flight experimentation of atmospheric re-entry enabling systems and technologies. The IXV integrates key technologies at the system level, with significant advancements on Europe's previous flying test-beds. The project builds on previous achievements at system and technology levels, and provides a unique and concrete way of establishing and consolidating Europe's autonomous position in the strategic field of atmospheric re-entry. The IXV mission and system objectives are the design, development, manufacturing, assembling and on-ground to in-flight verification of an autonomous European lifting and aerodynamically controlled reentry system, integrating critical re-entry technologies at system level. Among such critical technologies of interest, special attention is paid to aerodynamic and aerothermodynamics experimentation, including advanced instrumentation for aerothermodynamics phenomena investigations, thermal protections and hot-structures, guidance, navigation and flight control through combined jets and aerodynamic surfaces (i.e. flaps), in particular focusing on the technologies integration at system level for flight. Following the extensive detailed design, manufacturing, qualification, integration and testing of the flight segment and ground segment elements, IXV has performed a full successful flight on February 11th 2015. After the launch with the VEGA launcher form the CSG spaceport in French Guyana, IXV has performed a full nominal mission ending with a successful splashdown in the Pacific Ocean. During Flight Phase, the IXV space and ground segments worked perfectly, implementing the whole flight program in line with the commanded maneuvers and trajectory prediction, performing an overall flight of 34.400 km including 7.600 km with hot atmospheric re-entry in automatic guidance, concluding with successful precision landing at a distance of ~1

  13. Workforce re-entry for Japanese unemployed dental hygienists.

    Science.gov (United States)

    Usui, Y; Miura, H

    2015-02-01

    The aim of this study was to define the profile of unemployed dental hygienists who could be enticed to re-enter the workforce and the factors that could facilitate their re-entry into the dental field in Japan. The questionnaire was mailed with a postage-paid return envelope to a sample of 3095 licensed dental hygienists. A 50.4% response rate (S = 1477) was observed. The rate of working dental hygienists was 60.3% (n = 891), and of unemployed dental hygienists was 39.7% (n = 586). Of the latter, 31.9% (n = 187) stated intentions of returning to the workplace. The unemployed dental hygienists seeking employment were more often married and had more children, compared with working dental hygienists currently. This group also had significantly fewer total service years. Moreover, only 11.96% of them belonged to the Japan Dental Hygienists' Association, and 41.3% of those attended training workshops. According to their response, they perceived their top three major barriers to re-entry as 'lack sufficient dental hygiene skill', 'child rearing' and 'poor working atmosphere'. 'Flexibility in the work schedule' and 'location' were the most important factors for re-entry from their perspective. There were not many dental hygienists hoping to return to the dental field. The findings suggested that strategies to encourage non-practicing dental hygienists to re-entry should be emphasized in the areas of a flexible working atmosphere, easy access to information on how to return to practice and guidance on how to maintain professionalism during inactivity. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  14. Multiple Re-entry Closures After TEVAR for Ruptured Chronic Post-dissection Thoraco-abdominal Aortic Aneurysm

    Directory of Open Access Journals (Sweden)

    R. Kinoshita

    Full Text Available Introduction: Although thoracic endovascular aortic repair (TEVAR has become a promising treatment for complicated acute type B dissection, its role in treating chronic post-dissection thoraco-abdominal aortic aneurysm (TAA is still limited owing to persistent retrograde flow into the false lumen (FL through abdominal or iliac re-entry tears. Report: A case of chronic post-dissection TAA treatment, in which a dilated descending FL ruptured into the left thorax, is described. The primary entry tear was closed by emergency TEVAR and multiple abdominal re-entries were closed by EVAR. In addition, major re-entries at the detached right renal artery and iliac bifurcation were closed using covered stents. To close re-entries as far as possible, EVAR was carried out using the chimney technique, and additional aortic extenders were placed above the coeliac artery. A few re-entries remained, but complete FL thrombosis of the rupture site was achieved. Follow-up computed tomography showed significant shrinkage of the FL. Discussion: In treating post-dissection TAA, entry closure by TEVAR is sometimes insufficient, owing to persistent retrograde flow into the FL from abdominal or iliac re-entries. Adjunctive techniques are needed to close these distal re-entries to obtain complete FL exclusion, especially in rupture cases. Recently, encouraging results of complete coverage of the thoraco-abdominal aorta with fenestrated or branched endografts have been reported; however, the widespread employment of such techniques appears to be limited owing to technical difficulties. The present method with multiple re-entry closures using off the shelf and immediately available devices is an alternative for the endovascular treatment of post-dissection TAA, especially in the emergency setting. Keywords: Aortic dissection, Ruptured aortic aneurysm, Post-dissection thoracoabdominal aortic aneurysm, Endovascular aortic repair, Reentry closure, Endovascular procedures

  15. 75 FR 22813 - Guidance for Industry: Requalification Method for Reentry of Blood Donors Deferred Because of...

    Science.gov (United States)

    2010-04-30

    ...] Guidance for Industry: Requalification Method for Reentry of Blood Donors Deferred Because of Reactive Test... availability of a document entitled ``Guidance for Industry: Requalification Method for Reentry of Blood Donors... document entitled ``Guidance for Industry: Requalification Method for Reentry of Blood Donors Deferred...

  16. Socio-Economic status of parents as a correlate of re-entry of girls ...

    African Journals Online (AJOL)

    economic status (SES) and re-entry of girls into school in Edo State, Nigeria. One research question and one hypothesis were formulated for the study. Two research instruments, the “Socio-Economic Status of Parents” and the “Reentry into ...

  17. Behavioral health problems, ex-offender reentry policies, and the "Second Chance Act".

    Science.gov (United States)

    Pogorzelski, Wendy; Wolff, Nancy; Pan, Ko-Yu; Blitz, Cynthia L

    2005-10-01

    The federal "Second Chance Act of 2005" calls for expanding reentry services for people leaving prison, yet existing policies restrict access to needed services for those with criminal records. We examined the interaction between individual-level characteristics and policy-level restrictions related to criminal conviction, and the likely effects on access to resources upon reentry, using a sample of prisoners with Axis I mental disorders (n=3073). We identified multiple challenges related to convictions, including restricted access to housing, public assistance, and other resources. Invisible punishments embedded within existing policies were inconsistent with the call for second chances. Without modification of federal and state policies, the ability of reentry services to foster behavioral health and community reintegration is limited.

  18. Neural Dynamic Trajectory Design for Reentry Vehicles (Preprint)

    National Research Council Canada - National Science Library

    Verma, Ajay; Xu, Peng; Vadakkeveedu, Kalyan; Mayer, Rick

    2007-01-01

    The next generation of reentry vehicles is envisioned to have onboard autonomous capability of real-time trajectory planning to provide capability of responsive launch and delivering payload anywhere...

  19. Right Atrial Dual-loop Reentry Tachycardia after Cardiac Surgery: Prevalence, Electrophysiologic Characteristics and Ablation Outcomes.

    Science.gov (United States)

    Yang, Jian-du; Sun, Qi; Guo, Xiao-Gang; Zhou, Gong-Bu; Liu, Xu; Luo, Bin; Wei, Hui-Qiang; Santangeli, Pasquale; Liang, Jackson J; Ma, Jian

    2018-04-03

    Right atrial dual-loop reentry tachycardia has been described in patients with open-heart surgery. However, the prevalence, electrophysiologic substrate and ablation outcomes have been poorly characterized. We aimed to investigate the prevalence, electrophysiologic substrate and ablation outcomes for RA dual-loop reentry tachycardia following cardiac surgery. We identified all patients with atrial tachycardia after cardiac surgery. We compared electrophysiologic findings and outcomes of those with RA dual-loop reentry tachycardia versus a control group of patients with RA macro-reentrant arrhythmias in the setting of linear RA free wall (FW) scar. Out of 127 patients with 152 post-surgical atrial tachycardias (ATs), 28 (18.4%) had diagnosis of RA dual-loop reentry and 24/28 (85.7%) had tricuspid annular (TA) reentry combined with FW incisional reentry. An incision length > 51.5mm along the FW predicted the substrate for a second loop. In 22/23 patients (95.7%) with initial ablation in the cavo-tricuspid isthmus, a change in the interval between Halo d to CS p could be recorded, while 15/23 patients (65.2%) had CS activation pattern change. Complete success was achieved in 25/28 (89.3%) and 64/69 (92.8%) in the dual-loop reentry and control groups, respectively. After mean follow-up of 33.9±24.2 months, 24/28 (85.7%) and 60/69 (86.95%) were free of arrhythmias after initial procedure in two groups. The prevalence of RA dual-loop reentry is 18.4% among ATs with prior atriotomy scar. A long incision should alert physician the possibility of the second loop at the FW. Halo and CS activation pattern are important clues for circuit transformation. Copyright © 2018. Published by Elsevier Inc.

  20. HIAD on ULA (HULA) Orbital Reentry Flight Experiment Concept

    Science.gov (United States)

    Dinonno, J. M.; Cheatwood, F. M.; Hughes, S. J.; Ragab, M. M.; Dillman, R. A.; Bodkin, R. J.; Zumwalt, C. H.; Johnson, R. K.

    2016-01-01

    heritage design compressed gas system to minimize development costs. The data will be captured to both an onboard recorder and a recorder that is jettisoned and recovered separately from the reentry vehicle to mitigate risk. This paper provides an overview, including the architecture and flight concept of operations, for the proposed HULA flight experiment.

  1. Cardiac re-entry dynamics and self-termination in DT-MRI based model of Human Foetal Heart

    Science.gov (United States)

    Biktasheva, Irina V.; Anderson, Richard A.; Holden, Arun V.; Pervolaraki, Eleftheria; Wen, Fen Cai

    2018-02-01

    The effect of human foetal heart geometry and anisotropy on anatomy induced drift and self-termination of cardiac re-entry is studied here in MRI based 2D slice and 3D whole heart computer simulations. Isotropic and anisotropic models of 20 weeks of gestational age human foetal heart obtained from 100μm voxel diffusion tensor MRI data sets were used in the computer simulations. The fiber orientation angles of the heart were obtained from the orientation of the DT-MRI primary eigenvectors. In a spatially homogeneous electrophysiological monodomain model with the DT-MRI based heart geometries, cardiac re-entry was initiated at a prescribed location in a 2D slice, and in the 3D whole heart anatomy models. Excitation was described by simplified FitzHugh-Nagumo kinetics. In a slice of the heart, with propagation velocity twice as fast along the fibres than across the fibers, DT-MRI based fiber anisotropy changes the re-entry dynamics from pinned to an anatomical re-entry. In the 3D whole heart models, the fiber anisotropy changes cardiac re-entry dynamics from a persistent re-entry to the re-entry self-termination. The self-termination time depends on the re-entry’s initial position. In all the simulations with the DT-MRI based cardiac geometry, the anisotropy of the myocardial tissue shortens the time to re-entry self-termination several folds. The numerical simulations depend on the validity of the DT-MRI data set used. The ventricular wall showed the characteristic transmural rotation of the helix angle of the developed mammalian heart, while the fiber orientation in the atria was irregular.

  2. High performance modeling of atmospheric re-entry vehicles

    International Nuclear Information System (INIS)

    Martin, Alexandre; Scalabrin, Leonardo C; Boyd, Iain D

    2012-01-01

    Re-entry vehicles designed for space exploration are usually equipped with thermal protection systems made of ablative material. In order to properly model and predict the aerothermal environment of the vehicle, it is imperative to account for the gases produced by ablation processes. In the case of charring ablators, where an inner resin is pyrolyzed at a relatively low temperature, the composition of the gas expelled into the boundary layer is complex and may lead to thermal chemical reactions that cannot be captured with simple flow chemistry models. In order to obtain better predictions, an appropriate gas flow chemistry model needs to be included in the CFD calculations. Using a recently developed chemistry model for ablating carbon-phenolic-in-air species, a CFD calculation of the Stardust re-entry at 71 km is presented. The code used for that purpose has been designed to take advantage of the nature of the problem and therefore remains very efficient when a high number of chemical species are involved. The CFD result demonstrates the need for such chemistry model when modeling the flow field around an ablative material. Modeling of the nonequilibrium radiation spectra is also presented, and compared to the experimental data obtained during Stardust re-entry by the Echelle instrument. The predicted emission from the CN lines compares quite well with the experimental results, demonstrating the validity of the current approach.

  3. ANNOTATED BIBLIOGRAPHY OF ASTRODYNAMICS AND RE-ENTRY MECHANICS,

    Science.gov (United States)

    A selected list of references in the fields of astronautics and re-entry mechanics is classified and discussed, and a comprehensive subject and author index is included for ease in locating the references. (Author)

  4. Users manual for Aerospace Nuclear Safety Program six-degree-of-freedom reentry simulation (TMAGRA6C)

    International Nuclear Information System (INIS)

    Sharbaugh, R.C.

    1990-02-01

    This report documents the updated six-degree-of-freedom reentry simulation TMAGRA6C used in the Aerospace Nuclear Safety Program, ANSP. The simulation provides for the inclusion of the effects of ablation on the aerodynamic stability and drag of reentry bodies, specifically the General Purpose Heat Source, GPHS. The existing six-degree-of-freedom reentry body simulations (TMAGRA6A and TMAGRA6B) used in the JHU/APL Nuclear Safety Program do not include aerodynamic effects resulting from geometric changes to the configuration due to ablation from reentry flights. A wind tunnel test was conducted in 1989 to obtain the effects of ablation on the hypersonic aerodynamics of the GPHS module. The analyzed data were used to form data sets which are included herein in tabular form. These are used as incremental aerodynamic inputs in the new TMAGRA6C six-degree-of-freedom reentry simulation. 20 refs., 13 figs., 2 tabs

  5. Investigation of plasma–surface interaction effects on pulsed electrostatic manipulation for reentry blackout alleviation

    International Nuclear Information System (INIS)

    Krishnamoorthy, S; Close, S

    2017-01-01

    The reentry blackout phenomenon affects most spacecraft entering a dense planetary atmosphere from space, due to the presence of a plasma layer that surrounds the spacecraft. This plasma layer is created by ionization of ambient air due to shock and frictional heating, and in some cases is further enhanced due to contamination by ablation products. This layer causes a strong attenuation of incoming and outgoing electromagnetic waves including those used for command and control, communication and telemetry over a period referred to as the ‘blackout period’. The blackout period may last up to several minutes and is a major contributor to the landing error ellipse at best, and a serious safety hazard in the worst case, especially in the context of human spaceflight. In this work, we present a possible method for alleviation of reentry blackout using electronegative DC pulses applied from insulated electrodes on the reentry vehicle’s surface. We study the reentry plasma’s interaction with a DC pulse using a particle-in-cell (PIC) model. Detailed models of plasma–insulator interaction are included in our simulations. The absorption and scattering of ions and electrons at the plasma–dielectric interface are taken into account. Secondary emission from the insulating surface is also considered, and its implications on various design issues is studied. Furthermore, we explore the effect of changing the applied voltage and the impact of surface physics on the creation and stabilization of communication windows. The primary aim of this analysis is to examine the possibility of restoring L- and S-band communication from the spacecraft to a ground station. Our results provide insight into the effect of key design variables on the response of the plasma to the applied voltage pulse. Simulations show the creation of pockets where electron density in the plasma layer is reduced three orders of magnitude or more in the vicinity of the electrodes. These pockets extend to

  6. Romance, recovery & community re-entry for criminal justice involved women: Conceptualizing and measuring intimate relationship factors and power.

    Science.gov (United States)

    Walt, Lisa C; Hunter, Bronwyn; Salina, Doreen; Jason, Leonard

    Researchers have suggested that interpersonal relationships, particularly romantic relationships, may influence women's attempts at substance abuse recovery and community re-entry after criminal justice system involvement. The present paper evaluates relational and power theories to conceptualize the influence of romantic partner and romantic relationship qualities on pathways in and out of substance abuse and crime. The paper then combines these conceptualizations with a complementary empirical analysis to describe an ongoing research project that longitudinally investigates these relational and power driven factors on women's substance abuse recovery and community re-entry success among former substance abusing, recently criminally involved women. This paper is designed to encourage the integration of theory and empirical analysis by detailing how each of these concepts are operationalized and measured. Future research and clinical implications are also discussed.

  7. Rio Blanco: nuclear operations and chimney reentry

    International Nuclear Information System (INIS)

    Woodruff, W.R.; Guido, R.S.

    1975-01-01

    Rio Blanco was the third experiment in the U.S. Atomic Energy Commission's Plowshare Program to develop technology to stimulate gas production from geologic formations not conducive to production by conventional means. The project was sponsored by CER Geonuclear Corporation, with the Lawrence Livermore Laboratory providing the explosives and several technical programs, such as spall measurement. Three nuclear explosives specifically designed for this application were detonated simultaneously in a minimum-diameter emplacement well using many commercially available but established-reliability components. The explosive system performed properly under extreme temperature and pressure conditions. Emplacement and stemming operations were designed with the aim of simplifying both the emplacement and reentry and fully containing the detonation products. An integrated command and control system was used with communication to all three explosives through a single coaxial cable. Reentry and the initial production testing are completed. To date 98 million standard ft 3 of chimney gas have been produced. (auth)

  8. Reincarceration Risk Among Men with Mental Illnesses Leaving Prison: A Risk Environment Analysis.

    Science.gov (United States)

    Barrenger, Stacey L; Draine, Jeffrey; Angell, Beth; Herman, Daniel

    2017-11-01

    Reentry interventions for persons with mental illness leaving prison have consisted primarily of linkage to mental health services and have produced mixed results on psychiatric and criminal recidivism. These interventions primarily focus on intra-individual risk factors. However, social and environmental factors may also increase risk of reincarceration by constraining choices and pro-social opportunities for community reintegration upon release from prison. In order to add to the knowledge base on understanding reincarceration risk for men with mental illnesses leaving prison, we examined interpersonal and environmental factors that exposed men to heightened risk for reincarceration. As part of a larger study examining the effectiveness of Critical Time Intervention for men with mental illness leaving prison, in-depth interviews were conducted with 28 men within 6 months of release from prison. Policies and practices at local and state levels, community conditions, and interpersonal obligation and conflict were identified as increasing risk for reincarceration.

  9. Drag De-Orbit Device: A New Standard Re-Entry Actuator for CubeSats

    Science.gov (United States)

    Guglielmo, David; Omar, Sanny R.; Bevilacqua, Riccardo

    2017-01-01

    With the advent of CubeSats, research in Low Earth Orbit (LEO) becomes possible for universities and small research groups. Only a handful of launch sites can be used, due to geographical and political restrictions. As a result, common orbits in LEO are becoming crowded due to the additional launches made possible by low-cost access to space. CubeSat design principles require a maximum of a 25-year orbital lifetime in an effort to reduce the total number of spacecraft in orbit at any time. Additionally, since debris may survive re-entry, it is ideal to de-orbit spacecraft over unpopulated areas to prevent casualties. The Drag Deorbit Device (D3) is a self-contained targeted re-entry subsystem intended for CubeSats. By varying the cross-wind area, the atmospheric drag can be varied in such a way as to produce desired maneuvers. The D3 is intended to be used to remove spacecraft from orbit to reach a desired target interface point. Additionally, attitude stabilization is performed by the D3 prior to deployment and can replace a traditional ADACS on many missions.This paper presents the hardware used in the D3 and operation details. Four stepper-driven, repeatedly retractable booms are used to modify the cross-wind area of the D3 and attached spacecraft. Five magnetorquers (solenoids) over three axes are used to damp rotational velocity. This system is expected to be used to improve mission flexibility and allow additional launches by reducing the orbital lifetime of spacecraft.The D3 can be used to effect a re-entry to any target interface point, with the orbital inclination limiting the maximum latitude. In the chance that the main spacecraft fails, a timer will automatically deploy the booms fully, ensuring the spacecraft will at the minimum reenter the atmosphere in the minimum possible time, although not necessarily at the desired target interface point. Although this does not reduce the risk of casualties, the 25-year lifetime limit is still respected, allowing

  10. "The stress will kill you": prisoner reentry as experienced by family members and the urgent need for support services.

    Science.gov (United States)

    Grieb, Suzanne M; Crawford, Amelia; Fields, Julie; Smith, Horace; Harris, Richard; Matson, Pamela

    2014-08-01

    The role of incarceration and community reentry after incarceration has been studied extensively for individual and community health; however, little attention has been given to the experiences of individuals who provide support to those in reentry. Through a community-academic partnership, seven focus groups were conducted with 39 individuals supporting a family member in reentry in the summer of 2012. The primary objectives of the focus groups were to explore community experiences and perspectives regarding providing support during a family member's reentry from a period of incarceration and any desired support for themselves during this time. Five themes emerged under a metatheme of stress, indicating that family members experience acute stress as a result of family reentry that adds to the chronic stress they already endure. Programs that acknowledge the difficult role of family members as supporters during an individual's reentry and provide support to them are desperately needed.

  11. Re-entry Adjustment and Job Embeddedness: The Mediating Role of Professional Identity in Indonesian Returnees.

    Science.gov (United States)

    Andrianto, Sonny; Jianhong, Ma; Hommey, Confidence; Damayanti, Devi; Wahyuni, Honey

    2018-01-01

    The present study examined the relationship between difficulty in re-entry adjustment and job embeddedness, considering the mediating role of sense of professional identity. The online data on demographic characteristics, difficulty on re-entry adjustment, sense of professional identity, and job embeddedness were collected from 178 Indonesian returnees from multiple organizations. The results showed that difficulty in re-entry adjustment was a significant predictor of a sense of professional identity; a sense of professional identity was a significant predictor of job embeddedness. Furthermore, sense of professional identity is an effective mediating variable, bridging the relationship between post-return conditions to the home country and work atmosphere. Finally, the key finding of this study was that sense of professional identity mediated the effect of difficulty in re-entry adjustment on job embeddedness. The theoretical and practical implications, study limitations, and future research needs of our findings are noted.

  12. Aerothermodynamics of generic re-entry vehicle with a series of aerospikes at nose

    Science.gov (United States)

    Yadav, Rajesh; Velidi, Gurunadh; Guven, Ugur

    2014-03-01

    Re-entry of a blunt nosed vehicle is one of the most intriguing problems in any space programme. Especially in light of various space tourism possibilities, there are many works concerning re-entry of commercial blunt nosed space vehicles. In this paper, a generic blunt body re-entry model represented by a hemisphere-cylinder, fitted axisymmetrically with an aerodisk aerospike at the nose is investigated numerically with commercially available control volume based axisymmetric flow solver. The scaled down re-entry model has a base diameter of 40 mm and an overall length of 100 mm. A 6 mm diameter aerospike fitted axisymmetrically at the nose has a hemispherical cap from which another aerospike of 4 mm diameter protrudes which again has a hemispherical cap. Two dimensional compressible, axisymmetric Navier Stokes Equations are solved for a turbulent hypersonic flow of a 5 species, chemically reacting air in thermal equilibrium with free stream conditions of Mach no., static pressure and temperature of 10.1, 16,066 Pa and 216.65 K, respectively. The results are compared with that of re-entry model without any aerospike. Among the cases investigated, the spiked blunt body having two aerospikes in series with lengths l1 and l2 equal to 30 and 20 respectively and overall length-to-diameter ratio of 1.5 showed a favourable reduction in the peak reattachment heat flux along with high reduction in aerodynamic drag and thus stands as a prospective case for blunt body nose configuration for hypersonic flight.

  13. Reentry Women and Feminist Therapy: A Career Counseling Model.

    Science.gov (United States)

    Christian, Connie; Wilson, Jean

    1985-01-01

    Using the tenets of feminist therapy, presents a career counseling model for reentry women. Describes goals, intervention strategies, and feminist tenets for each of three stages: stabilization; personal growth; and action. (MCF)

  14. 40 CFR 161.390 - Reentry protection data requirements.

    Science.gov (United States)

    2010-07-01

    ... could cause adverse effects on persons entering treated sites. In the last situation, reentry intervals... crop Nonfood Greenhouse Food crop Nonfood Forestry Domestic outdoor Indoor Test substance Data to... oncogenic effects or other adverse effects as evidenced by subchronic, chronic, and reproduction studies...

  15. Seismic Parameters of Mining-Induced Aftershock Sequences for Re-entry Protocol Development

    Science.gov (United States)

    Vallejos, Javier A.; Estay, Rodrigo A.

    2018-03-01

    A common characteristic of deep mines in hard rock is induced seismicity. This results from stress changes and rock failure around mining excavations. Following large seismic events, there is an increase in the levels of seismicity, which gradually decay with time. Restricting access to areas of a mine for enough time to allow this decay of seismic events is the main approach in re-entry strategies. The statistical properties of aftershock sequences can be studied with three scaling relations: (1) Gutenberg-Richter frequency magnitude, (2) the modified Omori's law (MOL) for the temporal decay, and (3) Båth's law for the magnitude of the largest aftershock. In this paper, these three scaling relations, in addition to the stochastic Reasenberg-Jones model are applied to study the characteristic parameters of 11 large magnitude mining-induced aftershock sequences in four mines in Ontario, Canada. To provide guidelines for re-entry protocol development, the dependence of the scaling relation parameters on the magnitude of the main event are studied. Some relations between the parameters and the magnitude of the main event are found. Using these relationships and the scaling relations, a space-time-magnitude re-entry protocol is developed. These findings provide a first approximation to concise and well-justified guidelines for re-entry protocol development applicable to the range of mining conditions found in Ontario, Canada.

  16. A School Reentry Program for Chronically Ill Children.

    Science.gov (United States)

    Worchel-Prevatt, Frances F.; Heffer, Robert W.; Prevatt, Bruce C.; Miner, Jennifer; Young-Saleme, Tammi; Horgan, Daniel; Lopez, Molly A.; Frankel, Lawrence; Rae, William A.

    1998-01-01

    Describes a school reintegration program aimed at overcoming the numerous psychological, physical, environmental, and family-based deterrents to school reentry for chronically ill children. The program uses a systems approach to children's mental health with an emphasis on multiple aspects of the child's environment (i.e., family, medical…

  17. Ischemic stroke associated with radio frequency ablation for nodal reentry

    International Nuclear Information System (INIS)

    Diaz M, Juan C; Duran R, Carlos E; Perafan B, Pablo; Pava M, Luis F

    2010-01-01

    Atrioventricular nodal reentry tachycardia is the most common type of paroxysmal supraventricular tachycardia. In those patients in whom drug therapy is not effective or not desired, radio frequency ablation is an excellent therapeutic method. Although overall these procedures are fast and safe, several complications among which ischemic stroke stands out, have been reported. We present the case of a 41 year old female patient with repetitive episodes of tachycardia due to nodal reentry who was treated with radiofrequency ablation. Immediately after the procedure she presented focal neurologic deficit consistent with ischemic stroke in the right medial cerebral artery territory. Angiography with angioplastia and abxicimab was performed and then tissue plasminogen activator (rtPA) was locally infused, with appropriate clinical and angiographic outcome.

  18. Astronauts McNair and Stewart prepare for reentry

    Science.gov (United States)

    1984-01-01

    Astronauts Ronald E. McNair and Robert L. Stewart prepare for the re-entry phase of the shuttle Challenger near the end of the 41-B mission. The are stationed behind the crew commander and pilot. Stewart is already wearing his helmet. McNair is stowing some of his gear.

  19. Utilizing Weather RADAR for Rapid Location of Meteorite Falls and Space Debris Re-Entry

    Science.gov (United States)

    Fries, Marc D.

    2016-01-01

    This activity utilizes existing NOAA weather RADAR imagery to locate meteorite falls and space debris falls. The near-real-time availability and spatial accuracy of these data allow rapid recovery of material from both meteorite falls and space debris re-entry events. To date, at least 22 meteorite fall recoveries have benefitted from RADAR detection and fall modeling, and multiple debris re-entry events over the United States have been observed in unprecedented detail.

  20. A New Concept for Atmospheric Reentry Optimal Guidance: An Inverse Problem Inspired Approach

    Directory of Open Access Journals (Sweden)

    Davood Abbasi

    2013-01-01

    Full Text Available This paper presents a new concept for atmospheric reentry online optimal guidance and control using a method called MARE G&C that exploits the different time scale featured by reentry dynamics. The new technique reaches a quasi-analytical solution and simplified computations, even considering both lift-to-drag ratio and aerodynamic roll as control variables; in addition, the paper offers a solution for the challenging path constraints issue, getting inspiration from the inverse problem methodology. The final resulting algorithm seems suitable for onboard predictive guidance, a new need for future space missions.

  1. EntrySat: A 3U CubeStat to study the reentry atmospheric environment

    Science.gov (United States)

    Anthony, Sournac; Raphael, Garcia; David, Mimoun; Jeremie, Chaix

    2016-04-01

    ISAE France Entrysat has for main scientific objective the study of uncontrolled atmospheric re-entry. This project, is developed by ISAE in collaboration with ONERA and University of Toulouse, is funded by CNES, in the overall frame of the QB50 project. This nano-satellite is a 3U Cubesat measuring 34*10*10 cm3, similar to secondary debris produced during the break up of a spacecraft. EntrySat will collect the external and internal temperatures, pressure, heat flux, attitude variations and drag force of the satellite between ≈150 and 90 km before its destruction in the atmosphere, and transmit them during the re-entry using the IRIDIUM satellite network. The result will be compared with the computations of MUSIC/FAST, a new 6-degree of freedom code developed by ONERA to predict the trajectory of space debris. In order to fulfil the scientific objectives, the satellite will acquire 18 re-entry sensors signals, convert them and compress them, thanks to an electronic board developed by ISAE students in cooperation with EREMS. In order to transmit these data every second during the re-entry phase, the satellite will use an IRIDIUM connection. In order to keep a stable enough attitudes during this phase, a simple attitude orbit and control system using magnetotorquers and an inertial measurement unit (IMU) is developed at ISAE by students. A commercial GPS board is also integrated in the satellite into Entry Sat to determine its position and velocity which are necessary during the re-entry phase. This GPS will also be used to synchronize the on-board clock with the real-time UTC data. During the orbital phase (≈2 year) EntrySat measurements will be recorded transmitted through a more classical "UHF/VHF" connection. Preference for presentation: Poster Most suitable session: Author for correspondence: Dr Raphael F. Garcia ISAE 10, ave E. Belin, 31400 Toulouse, France Raphael.GARCIA@isae.fr +33 5 61 33 81 14

  2. Automated Re-Entry System using FNPEG

    Science.gov (United States)

    Johnson, Wyatt R.; Lu, Ping; Stachowiak, Susan J.

    2017-01-01

    This paper discusses the implementation and simulated performance of the FNPEG (Fully Numerical Predictor-corrector Entry Guidance) algorithm into GNC FSW (Guidance, Navigation, and Control Flight Software) for use in an autonomous re-entry vehicle. A few modifications to FNPEG are discussed that result in computational savings -- a change to the state propagator, and a modification to cross-range lateral logic. Finally, some Monte Carlo results are presented using a representative vehicle in both a high-fidelity 6-DOF (degree-of-freedom) sim as well as in a 3-DOF sim for independent validation.

  3. 8 CFR 211.3 - Expiration of immigrant visas, reentry permits, refugee travel documents, and Form I-551.

    Science.gov (United States)

    2010-01-01

    ... permits, refugee travel documents, and Form I-551. 211.3 Section 211.3 Aliens and Nationality DEPARTMENT... Expiration of immigrant visas, reentry permits, refugee travel documents, and Form I-551. An immigrant visa, reentry permit, refugee travel document, or Form I-551 shall be regarded as unexpired if the rightful...

  4. Conjugate gradient optimization programs for shuttle reentry

    Science.gov (United States)

    Powers, W. F.; Jacobson, R. A.; Leonard, D. A.

    1972-01-01

    Two computer programs for shuttle reentry trajectory optimization are listed and described. Both programs use the conjugate gradient method as the optimization procedure. The Phase 1 Program is developed in cartesian coordinates for a rotating spherical earth, and crossrange, downrange, maximum deceleration, total heating, and terminal speed, altitude, and flight path angle are included in the performance index. The programs make extensive use of subroutines so that they may be easily adapted to other atmospheric trajectory optimization problems.

  5. Application of Taylor-Series Integration to Reentry Problems with Wind

    NARCIS (Netherlands)

    Bergsma, Michiel; Mooij, E.

    2016-01-01

    Taylor-series integration is a numerical integration technique that computes the Taylor series of state variables using recurrence relations and uses this series to propagate the state in time. A Taylor-series integration reentry integrator is developed and compared with the fifth-order

  6. Aerodynamics of the EXPERT Re-Entry Ballistic Vehicle

    Science.gov (United States)

    Kharitonov, A. M.; Adamov, N. P.; Mazhul, I. I.; Vasenyov, L. G.; Zvegintsev, V. I.; Muylaert, J. M.

    2009-01-01

    Since 2002 till now, experimental studies of the EXPERT reentry capsule have been performed in ITAM SB RAS wind tunnels. These studies have been performed in consecutive ISTC project No. 2109, 3151, and currently ongoing project No. 3550. The results of earlier studies in ITAM wind tunnels can be found in [1-4]. The present paper describes new data obtained for the EXPERT model.

  7. School Reentry for Children with Acquired Central Nervous Systems Injuries

    Science.gov (United States)

    Carney, Joan; Porter, Patricia

    2009-01-01

    Onset of acquired central nervous system (CNS) injury during the normal developmental process of childhood can have impact on cognitive, behavioral, and motor function. This alteration of function often necessitates special education programming, modifications, and accommodations in the education setting for successful school reentry. Special…

  8. The Role of Counselling and Parental Encouragement on Re-Entry of Adolescents into Secondary Schools in Abia State, Nigeria

    Science.gov (United States)

    Alika, Henrietta Ijeoma; Ohanaka, Blessing Ijeoma

    2013-01-01

    This paper examined the role of counselling, and parental encouragement on re-entry of adolescents into secondary school in Abia State, Nigeria. A total of 353 adolescents who re-entered school were selected from six secondary schools in the State through a simple random sampling technique. A validated questionnaire was used for data analysis.…

  9. Passivity analysis for a winged re-entry vehicle

    Energy Technology Data Exchange (ETDEWEB)

    Mooij, E. [Delft University of Technology, Faculty of Aerospace Engineering, Delft (Netherlands)

    2014-12-10

    Application of simple adaptive control (SAC) theory to the design of guidance and control systems for winged re-entry vehicles has been proven successful. To apply SAC to these non-linear and non-stationary systems, it needs to be Almost Strictly Passive (ASP), which is an extension of the Almost Strictly Positive Real (ASPR) condition for linear, time-invariant systems. To fulfill the ASP condition, the controlled, non-linear system has to be minimum-phase (i.e., the zero dynamics is stable), and there is a specific condition for the product of output and input matrix. Earlier studies indicate that even the linearised system is not ASPR. The two problems at hand are: 1) the system is non-minimum phase when flying with zero bank angle, and 2) whenever there is hybrid control, e.g., yaw control is established by combined reaction and aerodynamic control for the major part of flight, the second ASPR condition cannot be met. In this paper we look at both issues, the former related to the guidance system and the latter to the attitude-control system. It is concluded that whenever the nominal bank angle is zero, the passivity conditions can never be met, and guidance should be based on nominal commands and a redefinition of those whenever the error becomes too large. For the remaining part of the trajectory, the passivity conditions are marginally met, but it is proposed to add feedforward compensators to alleviate these conditions. The issue of hybrid control is avoided by redefining the controls with total control moments and adding a so-called control allocator. Deriving the passivity conditions for rotational motion, and evaluating these conditions along the trajectory shows that the (non-linear) winged entry vehicle is ASP. The sufficient conditions to apply SAC for attitude control are thus met.

  10. Advanced Technology and Mitigation (ATDM) SPARC Re-Entry Code Fiscal Year 2017 Progress and Accomplishments for ECP.

    Energy Technology Data Exchange (ETDEWEB)

    Crozier, Paul [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Howard, Micah [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Rider, William J. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Freno, Brian Andrew [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Bova, Steven W. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Carnes, Brian [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2017-09-01

    The SPARC (Sandia Parallel Aerodynamics and Reentry Code) will provide nuclear weapon qualification evidence for the random vibration and thermal environments created by re-entry of a warhead into the earth’s atmosphere. SPARC incorporates the innovative approaches of ATDM projects on several fronts including: effective harnessing of heterogeneous compute nodes using Kokkos, exascale-ready parallel scalability through asynchronous multi-tasking, uncertainty quantification through Sacado integration, implementation of state-of-the-art reentry physics and multiscale models, use of advanced verification and validation methods, and enabling of improved workflows for users. SPARC is being developed primarily for the Department of Energy nuclear weapon program, with additional development and use of the code is being supported by the Department of Defense for conventional weapons programs.

  11. In-Flight Imaging Systems for Hypervelocity and Re-Entry Vehicles, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — It is proposed to create a rugged, reliable, compact, standardized imaging system for hypervelocity and re-entry vehicles using sapphire windows, small imagers, and...

  12. Evaluation of the Positive Re-Entry in Corrections Program: A Positive Psychology Intervention With Prison Inmates.

    Science.gov (United States)

    Huynh, Kim H; Hall, Brittany; Hurst, Mark A; Bikos, Lynette H

    2015-08-01

    Two groups of male inmates (n = 31, n = 31) participated in the Positive Re-Entry in Corrections Program (PRCP). This positive psychology intervention focused on teaching offenders skills that facilitate re-entry into the community. Offenders participated in weekly lectures, discussions, and homework assignments focused on positive psychology principles. The two groups differed in duration of treatment (8 weeks and 12 weeks). Participants completed pre- and post-intervention measures of gratitude, hope, and life satisfaction. Using a 2 × 2 mixed design ANOVA, we hypothesized that the intervention (with two between-subjects levels of 8 and 12 weeks) and duration (with two repeated measures levels of pre and post) of treatment would moderate pre- to post-intervention change. Results indicated significant differences on pre- and post-intervention scores for both groups of offenders on all measures. The analysis did not yield statistically significant differences between groups, demonstrating no additive benefits from the inclusion of four additional sessions, thus saving time and money for correctional programming and funding. This research supports the use of positive psychology in prison interventions. © The Author(s) 2014.

  13. Reentry Orientation and Alumni Networking in U.S. Colleges and Universities with Agriculture and Natural Resources Programs. Survey Report.

    Science.gov (United States)

    Huntsberger, Paul E.

    This report presents results of a survey of U.S. postsecondary institutions with agriculture and natural resources programs, concerning institutional support for reentry orientation and alumni networking programs. Reentry orientation" involves programs that help international students become aware of the adjustment aspects of returning home,…

  14. Re-entry experiences of Black men living with HIV/AIDS after release from prison: Intersectionality and implications for care.

    Science.gov (United States)

    Sun, Shufang; Crooks, Natasha; Kemnitz, Rebecca; Westergaard, Ryan P

    2018-06-12

    Both the HIV epidemic and incarceration disproportionately affect Black men in the United States. A critical period for incarcerated Black men living with HIV/AIDS is re-entry into the community, which is often associated with adverse health outcomes. Additionally, Black men living with HIV/AIDS involved in the criminal justice system are burdened by multiple, intersecting disadvantaged identities and social positions. This study aimed to examine community re-entry experiences among Black men living with HIV/AIDS from an intersectional perspective. In-depth, semi-structured interviews were conducted with 16 incarcerated Black men in Wisconsin, at pre-release from prison and six months after re-entry. Thematic analysis guided by intersectionality theory was used to analyze interview transcripts. Seven emerged themes included Intersectional Identities and Social Positions, Family Support, Neighborhood Violence, Relationship with Law Enforcement, Employment, Mental Health Concerns, and Medical Care and Medication Management. Intersecting identities and social positions interact with factors at multiple levels to inform health and HIV care. A conceptual framework was developed to illustrate relationships among themes. Findings demonstrate the relevance of intersectionality theory in HIV care with Black men involved in criminal justice system. Incorporating a social-ecological perspective into intersectionality framework could be useful in theoretical and empirical research. Disenfranchised communities may particularly benefit from interventions that address community- and systemic-level issues. Copyright © 2018 Elsevier Ltd. All rights reserved.

  15. Maternal Separations During the Reentry Years for 100 Infants Raised in a Prison Nursery

    Science.gov (United States)

    Byrne, Mary W.; Goshin, Lorie; Blanchard-Lewis, Barbara

    2011-01-01

    Prison nurseries prevent maternal separations related to incarceration for the small subset of children whose pregnant mothers are incarcerated in states with such programs. For a cohort of 100 children accepted by corrections into one prison nursery, subsequent separation patterns are analyzed. The largest numbers are caused by corrections’ removal of infants from the nursery and infants reaching a one-year age limit. Criminal recidivism and substance abuse relapse threaten continued mothering during reentry. Focused and coordinated services are needed during prison stay and reentry years to sustain mothering for women and children accepted into prison nursery programs. PMID:22328865

  16. The impact of prison reentry services on short-term outcomes: evidence from a multisite evaluation.

    Science.gov (United States)

    Lattimore, Pamela K; Visher, Christy A

    2013-01-01

    Renewed interest in prisoner rehabilitation to improve postrelease outcomes occurred in the 1990s, as policy makers reacted to burgeoning prison populations with calls to facilitate community reintegration and reduce recidivism. In 2003, the Federal government funded grants to implement locally designed reentry programs. Adult programs in 12 states were studied to determine the effects of the reentry programs on multiple outcomes. A two-stage matching procedure was used to examine the effectiveness of 12 reentry programs for adult males. In the first stage, "intact group matching" was used to identify comparison populations that were similar to program participants. In the second stage, propensity score matching was used to adjust for remaining differences between groups. Propensity score weighted logistic regression was used to examine the impact of reentry program participation on multiple outcomes measured 3 months after release. The study population was 1,697 adult males released from prisons in 2004-2005. Data consisted of interview data gathered 30 days prior to release and approximately 3 months following release, supplemented by administrative data from state departments of correction and the National Crime Information Center. Results suggest programs increased in-prison service receipt and produced modest positive outcomes across multiple domains (employment, housing, and substance use) 3 months after release. Although program participants reported fewer crimes, differences in postrelease arrest and reincarceration were not statistically significant. Incomplete implementation and service receipt by comparison group members may have resulted in insufficient statistical power to identify stronger treatment effects.

  17. Examining the Effects of Intensive Supervision and Aftercare Programs for At-Risk Youth: A Systematic Review and Meta-Analysis.

    Science.gov (United States)

    Bouchard, Jessica; Wong, Jennifer S

    2018-05-01

    Community correctional sentences are administered to more juvenile offenders in North America than any other judicial sentence. Particularly prominent in juvenile corrections is intensive supervision probation and aftercare/reentry, yet the effects of these supervision-oriented interventions on recidivism are mixed. The purpose of this meta-analysis is to determine the effects of intensive supervision probation and aftercare/reentry on juvenile recidivism. An extensive search of the literature and application of strict inclusion criteria resulted in the selection of 27 studies that contributed 55 individual effect sizes. Studies were pooled based on intervention type (intensive supervision probation or aftercare/reentry) and outcome measure (alleged or convicted offenses). The pooled analyses yielded contradictory results with respect to outcome measure; in both cases, supervision had a beneficial effect on alleged offenses and negatively affected convicted offenses. These patterns across intervention type and outcome measure, as well as recommendations for future research, are discussed.

  18. Re-entry simulation chamber for thermo-mechanical characterisation of space materials

    Science.gov (United States)

    Liedtke, Volker

    2003-09-01

    During re-entry, materials and components are subject to very high thermal and mechanical loads. Any failure may cause loss of mission. Therefore, materials and components have to be tested under most rigid conditions to verify the suitability of the material and to verify the design of the components. The Re-Entry Simulation Chamber (RESiC) at ARC Seibersdorf research (ARCS) allows simulating the high thermal loads as well as complex mechanical load profiles that may occur during a re-entry; additionally, the influence of chemical reactions of materials with gaseous components of the atmosphere can be studied. The high vacuum chamber (better than 1×10-6 mbar) has a diameter of 650 mm and allows a sample height of 500 mm, or 1000 mm with extension flange. The gas dosing system is designed to emulate the increasing atmospheric pressure during the re-entry trajectory of a vehicle. Heating is performed by a 30 kW induction generator that allows a sufficiently rapid heating of larger components; electrically conductive materials such as metals or carbon fibre reinforced ceramics are directly heated, while for electrical insulators, susceptor plates or tubes will be employed. The uniaxial servo-hydraulic testing machine has a maximum load of 70 kN, either static or with a frequency of up to 70 Hz, with any given load profile (sinus, rectangular, triangular, ...). Strain measurements will be done by non-contacting laser speckle system for maximum flexibility and minimum instrumentation time effort (currently under application testing), or by strain gauges. All relevant process parameters are controlled and recorded by microcomputer. The highly sophisticated control software allows a convenient and reliable multi-channel data acquisition, e.g. temperatures at various positions of the test piece, pressure, loads, strains, and any other test data according to customer specifications; the data format is suitable for any further data processing. During the set-up and

  19. The Secret of Guided Missile Re-Entry,

    Science.gov (United States)

    1986-06-25

    I RD-PAI169 598 THE SECRET OF GUIDED MISSILE RE-ENTRY(U) FOREIGN / I TECHNOLOGY DIV NRIGHT-PATTERSON RFB OH J CHEN ET AL. I 25 JUN 96 FTD-ID(RS)T...TECHNOLOGY DIVISION THE SECRET OF GUIDED MISSILE RE-ENTRY by Chen Jingzhong, An Sehua J L 0 7 ’:;85’ ’ 0 *Approved for public release; Distribution...unlimite t d. :. 86 7 034.. FTD- ID(RS)T-0459-86 HUMAN TRANSLATION FTD-ID(RS)T-0459-86 25 June 1986 MICROFICHE NR: F - - 0Q 9? THE SECRET OF GUIDED

  20. Measuring the spectral emissivity of thermal protection materials during atmospheric reentry simulation

    Science.gov (United States)

    Marble, Elizabeth

    1996-01-01

    Hypersonic spacecraft reentering the earth's atmosphere encounter extreme heat due to atmospheric friction. Thermal Protection System (TPS) materials shield the craft from this searing heat, which can reach temperatures of 2900 F. Various thermophysical and optical properties of TPS materials are tested at the Johnson Space Center Atmospheric Reentry Materials and Structures Evaluation Facility, which has the capability to simulate critical environmental conditions associated with entry into the earth's atmosphere. Emissivity is an optical property that determines how well a material will reradiate incident heat back into the atmosphere upon reentry, thus protecting the spacecraft from the intense frictional heat. This report describes a method of measuring TPS emissivities using the SR5000 Scanning Spectroradiometer, and includes system characteristics, sample data, and operational procedures developed for arc-jet applications.

  1. Facilitation of school re-entry and peer acceptance of children with cancer

    DEFF Research Database (Denmark)

    Helms, A. S.; Schmiegelow, K.; Brok, J.

    2016-01-01

    Increased survival rates from childhood cancer call for efforts to reintegrate children with cancer back into their academic and social environments. The aims of this study were to: (1) review and analyse the existing literature on school re-entry interventions for children with cancer; and (2......) discuss the importance of peer involvement in the treatment. Relevant databases were searched using equivalent search algorithms and six studies were selected that target children with cancer and/or their classmates. Two authors independently reviewed the literature for data extraction. The articles were...... reviewed using the PRISMA model for reporting reviews. Statistical calculations for the meta-analyses were done using Review Manager 5.2. The metaanalyses showed significant effects of school re-entry programmes in terms of enhancing academic achievement in children with cancer (P = 0.008) and lowering...

  2. Career Reentry Strategies for Highly Educated, Stay-at-Home Mothers

    Science.gov (United States)

    Guc, Cheryl M.

    2017-01-01

    Most stay-at-home mothers wish to return to the workplace; yet, the majority are not successful. There is a looming labor shortage and increasing organizational initiatives to increase female participation at most levels, providing opportunity for this talent pool. The purpose of this descriptive study was to examine the reentry strategies of…

  3. Re-Entry Women Students in Higher Education: A Model for Non-Traditional Support Programs in Counseling and Career Advisement.

    Science.gov (United States)

    Karr-Kidwell, PJ

    A model program of support for non-traditional women students has been developed at Texas Woman's University (TWU). Based on a pilot study, several steps were taken to assist these re-entry students at TWU. For example, in spring semester of 1983, a committee for re-entry students was established, with a student organization--Women in…

  4. Automated scheme to determine design parameters for a recoverable reentry vehicle

    International Nuclear Information System (INIS)

    Williamson, W.E.

    1976-01-01

    The NRV (Nosetip Recovery Vehicle) program at Sandia Laboratories is designed to recover the nose section from a sphere cone reentry vehicle after it has flown a near ICBM reentry trajectory. Both mass jettison and parachutes are used to reduce the velocity of the RV near the end of the trajectory to a sufficiently low level that the vehicle may land intact. The design problem of determining mass jettison time and parachute deployment time in order to ensure that the vehicle does land intact is considered. The problem is formulated as a min-max optimization problem where the design parameters are to be selected to minimize the maximum possible deviation in the design criteria due to uncertainties in the system. The results of the study indicate that the optimal choice of the design parameters ensures that the maximum deviation in the design criteria is within acceptable bounds. This analytically ensures the feasibility of recovery for NRV

  5. From the inside/out: Greene County jail inmates on restorative reentry.

    Science.gov (United States)

    Hass, Aida Y; Saxon, Caryn E

    2012-10-01

    The application of criminal justice sanctions is often misguided by a failure to recognize the need for a comprehensive approach in the transformation of offenders into law-abiding citizens. Restorative justice is a growing movement within criminal justice that recognizes the disconnect between offender rehabilitative measures and the social dynamics within which offender reentry takes place. By using restorative approaches to justice, what one hopes of these alternative processes is that the offenders become reconnected to the community and its values, something rarely seen in retributive models in which punishment is imposed and offenders can often experience further alienation from society. In this study, the authors wish to examine factors that contribute to failed prisoner reentry and reintegration and explore how restorative reintegration processes can address these factors as well as the needs, attitudes, and perceptions that help construct and maintain many of the obstacles and barriers returning inmates face when attempting to reintegrate into society.

  6. Improved MPSP Method-based Cooperative Re-entry Guidance for Hypersonic Gliding Vehicles

    Directory of Open Access Journals (Sweden)

    Chu Haiyan

    2017-01-01

    Full Text Available A computationally sufficient technique is used to solve the 3-D cooperative re-entry guidance problem for hypersonic gliding vehicles. Due to the poor surrounding adaptive ability of the traditional cooperative guidance methods, a novel methodology, named as model predictive static programming (MPSP, is used to solve a class of finite-horizon optimal control problems with hard terminal constraints. The main feature of this guidance law is that it is capable of hitting the target with high accuracy for each one of the cooperative vehicles at the same time. In addition, it accurately satisfies variable constraints. Performance of the proposed MPSP-based guidance is demonstrated in 3-D nonlinear dynamics scenario. The numerical simulation results show that the proposed cooperative re-entry guidance methodology has the advantage of computational efficiency and better robustness against the perturbations.

  7. Psychophysiological assessment and correction of spatial disorientation during simulated Orion spacecraft re-entry.

    Science.gov (United States)

    Cowings, Patricia S; Toscano, William B; Reschke, Millard F; Tsehay, Addis

    2018-03-02

    The National Aeronautics and Space Administration (NASA) has identified a potential risk of spatial disorientation, motion sickness, and degraded performance to astronauts during re-entry and landing of the proposed Orion crew vehicle. The purpose of this study was to determine if a physiological training procedure, Autogenic-Feedback Training Exercise (AFTE), can mitigate these adverse effects. Fourteen men and six women were assigned to two groups (AFTE, no-treatment Control) matched for motion sickness susceptibility and gender. All subjects received a standard rotating chair test to determine motion sickness susceptibility; three training sessions on a manual performance task; and four exposures in the rotating chair (Orion tests) simulating angular accelerations of the crew vehicle during re-entry. AFTE subjects received 2 h of training before Orion tests 2, 3, and 4. Motion sickness symptoms, task performance, and physiological measures were recorded on all subjects. Results showed that the AFTE group had significantly lower symptom scores when compared to Controls on test 2 (p = .05), test 3 (p = .03), and test 4 (p = .02). Although there were no significant group differences on task performance, trends showed that AFTE subjects were less impaired than Controls. Heart rate change scores (20 rpm minus baseline) of AFTE subjects indicated significantly less reactivity on Test 4 compared to Test 1 (10.09 versus 16.59, p = .02), while Controls did not change significantly across tests. Results of this study indicate that AFTE may be an effective countermeasure for mitigating spatial disorientation and motion sickness in astronauts. Copyright © 2018. Published by Elsevier B.V.

  8. Direct Simulation of Reentry Flows with Ionization

    Science.gov (United States)

    Carlson, Ann B.; Hassan, H. A.

    1989-01-01

    The Direct Simulation Monte Carlo (DSMC) method is applied in this paper to the study of rarefied, hypersonic, reentry flows. The assumptions and simplifications involved with the treatment of ionization, free electrons and the electric field are investigated. A new method is presented for the calculation of the electric field and handling of charged particles with DSMC. In addition, a two-step model for electron impact ionization is implemented. The flow field representing a 10 km/sec shock at an altitude of 65 km is calculated. The effects of the new modeling techniques on the calculation results are presented and discussed.

  9. Linear quadratic regulator design for an unpowered, winged re-entry vehicle

    NARCIS (Netherlands)

    Mooij, E.

    1998-01-01

    This report describes the design of an attitude controller for an unpowered, winged re-entry vehicle. The decoupling of the symmetric and asymmetric motion makes it possible to design two separate controllers, one for the pitch mot ion and one for the lateral motion. The design of the controller, a

  10. Reentry planning: The technical basis for offsite recovery following warfare agent contamination

    Energy Technology Data Exchange (ETDEWEB)

    Watson, A.P.; Munro, N.B.

    1990-04-01

    In the event on an unplanned release of chemical agent during any stage of Chemical Stockpile Disposal Program (CSDP), the potential exists for contamination of drinking water, forage crops, grains, garden produce and livestock. Persistent agents, such as VX or sulfur mustard, pose the greatest human health concern for reentry. The purpose of this technical support study is to provide information and analyses that can be used by federal, state and local emergency planners in determining the safety or reentry to, as well as the potential for recovery of, contaminated or suspect areas beyond the installation boundary. Guidelines for disposition of livestock, agricultural crops and personal/real property are summarized. Advisories for ingestion of food crops, water, meat and milk from the affected zones are proposed. This document does not address potential adverse effects to, or agent contamination of, wild species of plants or animals. 80 refs., 4 figs., 29 tabs.

  11. The Reach and Limitation of the ADA and its Integration Mandate: Implications for the Successful Reentry of Individuals with Mental Disabilities in a Correctional Population.

    Science.gov (United States)

    Dlugacz, Henry A; Droubi, Luna

    2017-03-01

    This article argues that the ADA and its integration mandate, informed by international standards, should extend to incarcerated individuals with mental disabilities who reenter society, as they are at highly elevated risk for unnecessary segregation in institutions such as homeless shelters or hospitals or through reincarceration. An understanding of the precise services needed to prevent these strongly related but distinct variants of institutionalization requires a robust and continuing research agenda. In discussing the breadth of the ADA, we explore its history, interpretations of its application in a variety of contexts with respect to vulnerable populations and integration, and enforcement. We also turn to international approaches to integration mandates as they apply to reentry. By interpreting the domestic and international principles that create the context for integration we hope to have provided a resource for future application of the ADA integration in the context of prisoner reentry. Copyright © 2017 John Wiley & Sons, Ltd. Copyright © 2017 John Wiley & Sons, Ltd.

  12. Mitigating reentry radio blackout by using a traveling magnetic field

    Directory of Open Access Journals (Sweden)

    Hui Zhou

    2017-10-01

    Full Text Available A hypersonic flight or a reentry vehicle is surrounded by a plasma layer that prevents electromagnetic wave transmission, which results in radio blackout. The magnetic-window method is considered a promising means to mitigate reentry communication blackout. However, the real application of this method is limited because of the need for strong magnetic fields. To reduce the required magnetic field strength, a novel method that applies a traveling magnetic field (TMF is proposed in this study. A mathematical model based on magneto-hydrodynamic theory is adopted to analyze the effect of TMF on plasma. The mitigating effects of the TMF on the blackout of typical frequency bands, including L-, S-, and C-bands, are demonstrated. Results indicate that a significant reduction of plasma density occurs in the magnetic-window region by applying a TMF, and the reduction ratio is positively correlated with the velocity of the TMF. The required traveling velocities for eliminating the blackout of the Global Positioning System (GPS and the typical telemetry system are also discussed. Compared with the constant magnetic-window method, the TMF method needs lower magnetic field strength and is easier to realize in the engineering field.

  13. Mitigating reentry radio blackout by using a traveling magnetic field

    Science.gov (United States)

    Zhou, Hui; Li, Xiaoping; Xie, Kai; Liu, Yanming; Yu, Yuanyuan

    2017-10-01

    A hypersonic flight or a reentry vehicle is surrounded by a plasma layer that prevents electromagnetic wave transmission, which results in radio blackout. The magnetic-window method is considered a promising means to mitigate reentry communication blackout. However, the real application of this method is limited because of the need for strong magnetic fields. To reduce the required magnetic field strength, a novel method that applies a traveling magnetic field (TMF) is proposed in this study. A mathematical model based on magneto-hydrodynamic theory is adopted to analyze the effect of TMF on plasma. The mitigating effects of the TMF on the blackout of typical frequency bands, including L-, S-, and C-bands, are demonstrated. Results indicate that a significant reduction of plasma density occurs in the magnetic-window region by applying a TMF, and the reduction ratio is positively correlated with the velocity of the TMF. The required traveling velocities for eliminating the blackout of the Global Positioning System (GPS) and the typical telemetry system are also discussed. Compared with the constant magnetic-window method, the TMF method needs lower magnetic field strength and is easier to realize in the engineering field.

  14. Predictors of homeless services re-entry within a sample of adults receiving Homelessness Prevention and Rapid Re-Housing Program (HPRP) assistance.

    Science.gov (United States)

    Brown, Molly; Vaclavik, Danielle; Watson, Dennis P; Wilka, Eric

    2017-05-01

    Local and national evaluations of the federal Homelessness Prevention and Rapid Re-Housing Program (HPRP) have demonstrated a high rate of placement of program participants in permanent housing. However, there is a paucity of research on the long-term outcomes of HPRP, and research on rehousing and prevention interventions for single adults experiencing homelessness is particularly limited. Using Homeless Management Information System data from 2009 to 2015, this study examined risk of return to homeless services among 370 permanently housed and 71 nonpermanently housed single adult HPRP participants in Indianapolis, Indiana. Kaplan-Meier survival curves were conducted to analyze time-to-service re-entry for the full sample, and the homelessness prevention and rapid rehousing participants separately. With an average follow-up of 4.5 years after HPRP exit, 9.5% of the permanently housed HPRP participants and 16.9% of those nonpermanently housed returned to homeless services. By assistance type, 5.4% of permanently housed and 15.8% of nonpermanently housed homelessness prevention recipients re-entered services, and 12.8% of permanently housed and 18.2% of nonpermanently housed rapid rehousing recipients re-entered during the follow-up period. Overall, veterans, individuals receiving rapid rehousing services, and those whose income did not increase during HPRP had significantly greater risk of returning to homeless services. Veterans were at significantly greater risk of re-entry when prevention and rehousing were examined separately. Findings suggest a need for future controlled studies of prevention and rehousing interventions for single adults, aiming to identify unique service needs among veterans and those currently experiencing homelessness in need of rehousing to inform program refinement. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

  15. Autogenic-Feedback Training Exercise (AFTE) Mitigates the Effects of Spatial Disorientation to Simulated Orion Spacecraft Re-Entry: Individual Differences

    Science.gov (United States)

    Cowings, Patricia S.; Toscano, William B.; Reschke, Millard F.; Gebreyesus, Fiyori; Rocha, Christopher

    2017-01-01

    NASA has identified a potential risk of spatial disorientation to future astronauts during re-entry of the proposed Orion spacecraft. The purpose of this study was to determine if a 6-hour physiological training procedure, Autogenic-Feedback Training Exercise (AFTE), can mitigate these effects. Twenty subjects were assigned to two groups (AFTE and Control) matched for motion sickness susceptibility and gender. All subjects received a standard rotating chair test to determine motion sickness susceptibility; three training sessions on a manual performance task; and four exposures to a simulated Orion re-entry test in the rotating chair. Treatment subjects were given two hours of AFTE training before each Orion test. A diagnostic scale was used to evaluate motion sickness symptom severity. Results showed that 2 hours of AFTE significantly reduced motion sickness symptoms during the second Orion test. AFTE subjects were able to maintain lower heart rates and skin conductance levels and other responses than the control group subjects during subsequent tests. Trends show that performance was less degraded for AFTE subjects. The results of this study indicate that astronauts could benefit from receiving at least 2 hours of preflight AFTE. In addition, flight crews could benefit further by practicing physiologic self-regulation using mobile devices.

  16. On-ground casualty risk reduction by structural design for demise

    Science.gov (United States)

    Lemmens, Stijn; Funke, Quirin; Krag, Holger

    2015-06-01

    In recent years, awareness concerning the on-ground risk posed by un-controlled re-entering space systems has increased. On average over the past decade, an object with mass above 800 kg re-enters every week from which only a few, e.g. ESA's GOCE in 2013 and NASA's UARS in 2011, appeared prominent in international media. Space agencies and nations have discussed requirements to limit the on-ground risk for future missions. To meet the requirements, the amount of debris falling back on Earth has to be limited in number, mass and size. Design for demise (D4D) refers to all measures taken in the design of a space object to increase the potential for demise of the object and its components during re-entry. SCARAB (Spacecraft Atmospheric Re-entry and Break-Up) is ESA's high-fidelity tool which analyses the thermal and structural effects of atmospheric re-entry on spacecraft with a finite-element approach. For this study, a model of a representative satellite is developed in SCARAB to serve as test-bed for D4D analyses on a structural level. The model is used as starting point for different D4D approaches based on increasing the exposure of the satellite components to the aero-thermal environment, as a way to speed up the demise. Statistical bootstrapping is applied to the resulting on-ground fragment lists in order to compare the different re-entry scenarios and to determine the uncertainties of the results. Moreover, the bootstrap results can be used to analyse the casualty risk estimator from a theoretical point of view. The risk reductions for the analysed D4D techniques are presented with respect to the reference scenario for the modelled representative satellite.

  17. Phospho-Rb mediating cell cycle reentry induces early apoptosis following oxygen-glucose deprivation in rat cortical neurons.

    Science.gov (United States)

    Yu, Ying; Ren, Qing-Guo; Zhang, Zhao-Hui; Zhou, Ke; Yu, Zhi-Yuan; Luo, Xiang; Wang, Wei

    2012-03-01

    The aim of this study was to investigate the relationship between cell cycle reentry and apoptosis in cultured cortical neurons following oxygen-glucose deprivation (OGD). We found that the percentage of neurons with BrdU uptake, TUNEL staining, and colocalized BrdU uptake and TUNEL staining was increased relative to control 6, 12 and 24 h after 1 h of OGD. The number of neurons with colocalized BrdU and TUNEL staining was decreased relative to the number of TUNEL-positive neurons at 24 h. The expression of phosphorylated retinoblastoma protein (phospho-Rb) was significantly increased 6, 12 and 24 h after OGD, parallel with the changes in BrdU uptake. Phospho-Rb and TUNEL staining were colocalized in neurons 6 and 12 h after OGD. This colocalization was strikingly decreased 24 h after OGD. Treatment with the cyclin-dependent kinase inhibitor roscovitine (100 μM) decreased the expression of phospho-Rb and reduced neuronal apoptosis in vitro. These results demonstrated that attempted cell cycle reentry with phosphorylation of Rb induce early apoptosis in neurons after OGD and there must be other mechanisms involved in the later stages of neuronal apoptosis besides cell cycle reentry. Phosphoralated Rb may be an important factor which closely associates aberrant cell cycle reentry with the early stages of neuronal apoptosis following ischemia/hypoxia in vitro, and pharmacological interventions for neuroprotection may be useful directed at this keypoint.

  18. "I Want a Second Chance": Experiences of African American Fathers in Reentry.

    Science.gov (United States)

    Dill, LeConté J; Mahaffey, Carlos; Mosley, Tracey; Treadwell, Henrie; Barkwell, Fabeain; Barnhill, Sandra

    2016-11-01

    With over 700,000 people on average released from prison each year to communities, greater attention is warranted on the experiences and needs of those who are parents and seeking to develop healthy relationships with their children and families. This study seeks to explore the experiences of African American fathers in reentry. Qualitative data from 16 African American men enrolled in a fellowship program for fathers were collected from a focus group and analyzed for common themes and using standpoint theory. Four themes emerged that focused on fathers' commitment toward healthy and successful reintegration postincarceration: redemption, employment, health care, and social support. Focus group participants actively strive to develop and rebuild healthy relationships with their children through seeking gainful employment and through bonding with like-minded peers. Barriers in accessing health care are also discussed. Research findings may inform future programs and policies related to supporting fathers and their children in reentry. © The Author(s) 2015.

  19. Recording animal vocalizations from a UAV: bat echolocation during roost re-entry.

    Science.gov (United States)

    Kloepper, Laura N; Kinniry, Morgan

    2018-05-17

    Unmanned aerial vehicles (UAVs) are rising in popularity for wildlife monitoring, but direct recordings of animal vocalizations have not yet been accomplished, likely due to the noise generated by the UAV. Echolocating bats, especially Tadarida brasiliensis, are good candidates for UAV recording due to their high-speed, high-altitude flight. Here, we use a UAV to record the signals of bats during morning roost re-entry. We designed a UAV to block the noise of the propellers from the receiving microphone, and report on the characteristics of bioacoustic recordings from a UAV. We report the first published characteristics of echolocation signals from bats during group flight and cave re-entry. We found changes in inter-individual time-frequency shape, suggesting that bats may use differences in call design when sensing in complex groups. Furthermore, our first documented successful recordings of animals in their natural habitat demonstrate that UAVs can be important tools for bioacoustic monitoring, and we discuss the ethical considerations for such monitoring.

  20. Lightweight Ultrahigh Temperature CMC-Encased C/C Structure for Reentry and Hypersonic Applications, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — Future reentry and hypersonic vehicles require advanced lightweight leading edge thermal protection systems that can provide the dual functionality of...

  1. High Fidelity Airborne Imaging System for Remote Observation of Space Launch/Reentry Systems, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — The utility of airborne remote observation of hypersonic reentry vehicles was demonstrated by the NASA Hypersonic Thermodynamic Infrared Measurement (HYTHIRM)...

  2. The effects of bedrest on crew performance during simulated shuttle reentry. Volume 2: Control task performance

    Science.gov (United States)

    Jex, H. R.; Peters, R. A.; Dimarco, R. J.; Allen, R. W.

    1974-01-01

    A simplified space shuttle reentry simulation performed on the NASA Ames Research Center Centrifuge is described. Anticipating potentially deleterious effects of physiological deconditioning from orbital living (simulated here by 10 days of enforced bedrest) upon a shuttle pilot's ability to manually control his aircraft (should that be necessary in an emergency) a comprehensive battery of measurements was made roughly every 1/2 minute on eight military pilot subjects, over two 20-minute reentry Gz vs. time profiles, one peaking at 2 Gz and the other at 3 Gz. Alternate runs were made without and with g-suits to test the help or interference offered by such protective devices to manual control performance. A very demanding two-axis control task was employed, with a subcritical instability in the pitch axis to force a high attentional demand and a severe loss-of-control penalty. The results show that pilots experienced in high Gz flying can easily handle the shuttle manual control task during 2 Gz or 3 Gz reentry profiles, provided the degree of physiological deconditioning is no more than induced by these 10 days of enforced bedrest.

  3. Thermal Response of Whipox-Type All-Oxide Ceramic Matrix Composites during Reentry Simulation in the Dlr-Lbk Arc-Heated Facility

    Science.gov (United States)

    Mechnich, P.; Braue, W.; Schneider, H.; Koch, U.; Esser, B.; Gülhan, A.

    2005-02-01

    All-oxide ceramic matrix composites (CMCs) such as WHIPOXTM (wound highly porous oxide) exhibit excellent damage tolerance and thermal stability up to 1400°C. Due to their low density and thermal conductivity these new ceramic materials are considered promising candidates for thermal protection systems (TPS) of spacecrafts. The performance of WHIPOX-type CMCs was evaluated during reentry simulations in the L2K leg of the arc-heated LBK facility of DLR, Cologne. The application of reaction-bonded alumina (RBAO) coatings provides significant CMC surface protection and decreased gas permeability, which are key issues for reentry applications. Since emittance and catalycity of the RBAO-coatings limit the performance of CMCs in a reentry environment, binary SiC/RBAO coatings providing higher emittance and/or lower catalycity proved to be a promising approach.

  4. Lightweight Ultrahigh Temperature CMC-Encased C/C Structure for Reentry and Hypersonic Applications, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — The reentry spacecraft and hypersonic cruisers of the future will require advanced lightweight thermal protection systems that can provide the dual functionality of...

  5. Hypersonic Cruise and Re-Entry Radio Frequency Blackout Mitigation: Alleviating the Communications Blackout Problem

    Science.gov (United States)

    Manning, Robert M.

    2017-01-01

    The work presented here will be a review of a NASA effort to provide a method to transmit and receive RF communications and telemetry through a re-entry plasma thus alleviating the classical RF blackout phenomenon.

  6. Exploring Efficacy in Negotiating Support: Women Re-Entry Students in Higher Education

    Science.gov (United States)

    Filipponi-Berardinelli, Josephine Oriana

    2013-01-01

    The existing literature on women re-entry students reveals that women students concurrently struggle with family, work, and sometimes health issues. Women students often do not receive adequate support from their partners or from other sources in helping manage the multiple roles that compete for their time, and often face constraints that affect…

  7. A Novel Device for True Lumen Re-Entry After Subintimal Recanalization of Superficial Femoral Arteries: First-in-Man Experience and Technical Description

    International Nuclear Information System (INIS)

    Airoldi, Flavio; Faglia, Ezio; Losa, Sergio; Tavano, Davide; Latib, Azeem; Mantero, Manuela; Lanza, Gaetano; Clerici, Giacomo

    2011-01-01

    Subintimal angioplasty (SAP) is frequently performed for the treatment of critical limb ischemia (CLI) and has been recognized as an effective technique for these patients. Nevertheless, this approach is limited by the lack of controlled re-entry into the true lumen of the target vessel. We describe a novel device for true lumen re-entry after subintimal recanalization of superficial femoral arteries (SFA). We report our experience with six patients treated between April 2009 and January 2010 with a novel system designed to facilitate true lumen re-entry. The device was advanced by ipsilateral antegrade approach through a 6-French sheath. Successful reaccess into the true lumen was obtained in five of six patients without complications. The patient in whom the reaccess to the true lumen was not possible underwent successful bypass surgery. At 30 days follow-up, the SFA was patent in all patients according to echo-Doppler examination. Our preliminary experience indicates that this novel re-entry device increases the success rate of percutaneous revascularization of chronically occluded SFA.

  8. Effects of Personality Correlates on Achievement Motivation in Traditional and Reentry College Women.

    Science.gov (United States)

    Johnson, Carolyn H.

    There is little literature comparing personality differences between traditional (under age 25) and reentry women students (aged 25 and older). The purpose of the present study is to examine these differences. A background questionnaire and five additional scales: (1) the Work and Family Orientation Questionnaire (WOFO-3); (2) the…

  9. Reusable Reentry Satellite (RRS): Propulsion system trade study

    Science.gov (United States)

    1990-01-01

    The purpose of the Reusable Reentry Satellite (RRS) Propulsion System Trade Study described in this summary report was to investigate various propulsion options available for incorporation on the RRS and to select the option best suited for RRS application. The design requirements for the RRS propulsion system were driven by the total impulse requirements necessary to operate within the performance envelope specified in the RRS System Requirements Documents. These requirements were incorporated within the Design Reference Missions (DRM's) identified for use in this and other subsystem trade studies. This study investigated the following propulsion systems: solid rocket, monopropellant, bipropellant (monomethyl hydrazine and nitrogen tetroxide or MMH/NTO), dual-mode bipropellant (hydrazine and nitrogen tetroxide or N2H4/NTO), liquid oxygen and liquid hydrogen (LO2/LH2), and an advanced design propulsion system using SDI-developed components. A liquid monopropellant blowdown propulsion system was found to be best suited for meeting the RRS requirements and is recommended as the baseline system. This system was chosen because it is the simplest of all investigated, has the fewest components, and is the most cost effective. The monopropellant system meets all RRS performance requirements and has the capability to provide a very accurate deorbit burn which minimizes reentry dispersions. In addition, no new hardware qualification is required for a monopropellant system. Although the bipropellant systems offered some weight savings capability for missions requiring large deorbit velocities, the advantage of a lower mass system only applies if the total vehicle design can be reduced to allow a cheaper launch vehicle to be used. At the time of this trade study, the overall RRS weight budget and launch vehicle selection were not being driven by the propulsion system selection. Thus, the added cost and complexity of more advanced systems did not warrant application.

  10. Information security risk analysis

    CERN Document Server

    Peltier, Thomas R

    2001-01-01

    Effective Risk AnalysisQualitative Risk AnalysisValue AnalysisOther Qualitative MethodsFacilitated Risk Analysis Process (FRAP)Other Uses of Qualitative Risk AnalysisCase StudyAppendix A: QuestionnaireAppendix B: Facilitated Risk Analysis Process FormsAppendix C: Business Impact Analysis FormsAppendix D: Sample of ReportAppendix E: Threat DefinitionsAppendix F: Other Risk Analysis OpinionsIndex

  11. Engagement processes in model programs for community reentry from prison for people with serious mental illness.

    Science.gov (United States)

    Angell, Beth; Matthews, Elizabeth; Barrenger, Stacey; Watson, Amy C; Draine, Jeffrey

    2014-01-01

    Linking prisoners with mental illness with treatment following release is critical to preventing recidivism, but little research exists to inform efforts to engage them effectively. This presentation compares the engagement process in two model programs, each representing an evidence-based practice for mental health which has been adapted to the context of prison reentry. One model, Forensic Assertive Community Treatment (FACT), emphasizes a long-term wrap-around approach that seeks to maximize continuity of care by concentrating all services within one interdisciplinary team; the other, Critical Time Intervention (CTI), is a time-limited intervention that promotes linkages to outside services and bolsters natural support systems. To compare engagement practices, we analyze data from two qualitative studies, each conducted in a newly developed treatment program serving prisoners with mental illness being discharged from prisons to urban communities. Findings show that the working relationship in reentry services exhibits unique features and is furthered in both programs by the use of practitioner strategies of engagement, including tangible assistance, methods of interacting with consumers, and encouragement of service use via third parties such as families and parole officers. Nevertheless, each program exhibited distinct cultures and rituals of reentry that were associated with fundamental differences in philosophy and differences in resources available to each program. Copyright © 2014 Elsevier Ltd. All rights reserved.

  12. Observer-based attitude controller for lifting re-entry vehicle with non-minimum phase property

    Directory of Open Access Journals (Sweden)

    Wenming Nie

    2017-05-01

    Full Text Available This article concentrates on the attitude control problem for the lifting re-entry vehicle with non-minimum phase property. A novel attitude control method is proposed for this kind of lifting re-entry vehicle without assuming the internal dynamics to be measurable. First, an internal dynamics extended state observer is developed to deal with the unmeasurable problem of the internal dynamics. And then, the control scheme which adopts output feedback method is proposed by modifying the traditional output redefinition technique with internal dynamics extended state observer. This control scheme only requires the system output to be measurable, and it can still stabilize the unstable internal dynamics and track attitude commands. Besides, because of the inherent property of extended state observer in rejecting uncertainties and disturbances, the control precision of the proposed controller is higher than the controller designed with traditional output redefinition technique. Finally, the effectiveness and robustness of the proposed attitude controller are demonstrated by the simulation results.

  13. Using the Design for Demise Philosophy to Reduce Casualty Risk Due to Reentering Spacecraft

    Science.gov (United States)

    Kelley, R. L.

    2012-01-01

    Recently the reentry of a number of vehicles has garnered public attention due to their risk of human casualty due to fragments surviving reentry. In order to minimize this risk for their vehicles, a number of NASA programs have actively sought to minimize the number of components likely to survive reentry at the end of their spacecraft's life in order to meet and/or exceed NASA safety standards for controlled and uncontrolled reentering vehicles. This philosophy, referred to as "Design for Demise" or D4D, has steadily been adopted, to at least some degree, by numerous programs. The result is that many programs are requesting evaluations of components at the early stages of vehicle design, as they strive to find ways to reduce the number surviving components while ensuring that the components meet the performance requirements of their mission. This paper will discuss some of the methods that have been employed to ensure that the consequences of the vehicle s end-of-life are considered at the beginning of the design process. In addition this paper will discuss the technical challenges overcome, as well as some of the more creative solutions which have been utilized to reduce casualty risk.

  14. Ceramic Adhesive and Methods for On-Orbit Repair of Re-Entry Vehicles

    Science.gov (United States)

    Riedell, James A.; Easler, Timothy E.

    2013-01-01

    This adhesive is capable of repairing damaged leading edge components of reentry vehicles while in space, and is novel with regard to its ability to be applied in the vacuum of space, and in a microgravity environment. Once applied, the adhesive provides thermal and oxidation protection to the substrate (in this case, reinforced carbon/carbon composites, RCCs) during re-entry of a space vehicle. Although there may be many formulations for repair adhesives, at the time of this reporting, this is the first known adhesive capable of an on-orbit repair. The adhesive is an engineered ceramic material composed of a pre-ceramic polymer and refractory powders in the form of a paste or putty that can be applied to a scratched, cracked, or fractured composite surface, covering and protecting the damaged area. The adhesive is then "cured" with a heat cycle, thereby cross-linking the polymer into a hardened material and bonding it to the substrate. During the heat of reentry, the material is converted to a ceramic coating that provides thermal and oxidative stability to the repaired area, thus allowing the vehicle to pass safely from space into the upper atmosphere. Ceramic powders such as SiC, ZrB2 and Y2O3 are combined with allylhydridopolycarbosilane (AHPCS) resin, and are mixed to form a paste adhesive. The material is then applied to the damaged area by brush, spatula, trowel, or other means to fill cracks, gaps, and holes, or used to bond patches onto the damaged area. The material is then cured, in a vacuum, preferably at 250F (approximately equal to 121C) for two hours. The re-entry heating of the vehicle at temperatures in excess of 3,000F (approximately equal to 1,650C) then converts this material into a ceramic coating. This invention has demonstrated advantages in resistance to high temperatures, as was demonstrated in more than 100 arc-jet tests in representative environments at NASA. Extensive testing verified oxidation protection for the repaired substrate (RCC

  15. Application of a Near Infrared Imaging System for Thermographic Imaging of the Space Shuttle during Hypersonic Re-Entry

    Science.gov (United States)

    Zalameda, Joseph N.; Tietjen, Alan B.; Horvath, Thomas J.; Tomek, Deborah M.; Gibson, David M.; Taylor, Jeff C.; Tack, Steve; Bush, Brett C.; Mercer, C. David; Shea, Edward J.

    2010-01-01

    High resolution calibrated near infrared (NIR) imagery was obtained of the Space Shuttle s reentry during STS-119, STS-125, and STS-128 missions. The infrared imagery was collected using a US Navy NP-3D Orion aircraft using a long-range infrared optical package referred to as Cast Glance. The slant ranges between the Space Shuttle and Cast Glance were approximately 26-41 nautical miles at point of closest approach. The Hypersonic Thermodynamic Infrared Measurements (HYTHIRM) project was a NASA Langley led endeavor sponsored by the NASA Engineering Safety Center, the Space Shuttle Program Office and the NASA Aeronautics Research Mission Directorate to demonstrate a quantitative thermal imaging capability. HYTHIRM required several mission tools to acquire the imagery. These tools include pre-mission acquisition simulations of the Shuttle trajectory in relationship to the Cast Glance aircraft flight path, radiance modeling to predict the infrared response of the Shuttle, and post mission analysis tools to process the infrared imagery to quantitative temperature maps. The spatially resolved global thermal measurements made during the Shuttle s hypersonic reentry provides valuable flight data for reducing the uncertainty associated with present day ground-to-flight extrapolation techniques and current state-of-the-art empirical boundary-layer transition or turbulent heating prediction methods. Laminar and turbulent flight data is considered critical for the development of turbulence models supporting NASA s next-generation spacecraft. This paper will provide the motivation and details behind the use of an upgraded NIR imaging system used onboard a Navy Cast Glance aircraft and describe the characterizations and procedures performed to obtain quantitative temperature maps. A brief description and assessment will be provided of the previously used analog NIR camera along with image examples from Shuttle missions STS-121, STS-115, and solar tower test. These thermal

  16. Entrainment and high-density three-dimensional mapping in right atrial macroreentry provide critical complementary information: Entrainment may unmask "visual reentry" as passive.

    Science.gov (United States)

    Pathik, Bhupesh; Lee, Geoffrey; Nalliah, Chrishan; Joseph, Stephen; Morton, Joseph B; Sparks, Paul B; Sanders, Prashanthan; Kistler, Peter M; Kalman, Jonathan M

    2017-10-01

    With the recent advent of high-density (HD) 3-dimensional (3D) mapping, the utility of entrainment is uncertain. However, the limitations of visual representation and interpretation of these high-resolution 3D maps are unclear. The purpose of this study was to determine the strengths and limitations of both HD 3D mapping and entrainment mapping during mapping of right atrial macroreentry. Fifteen patients were studied. The number and type of circuits accounting for ≥90% of the tachycardia cycle length using HD 3D mapping were verified using systematic entrainment mapping. Entrainment sites with an unexpectedly long postpacing interval despite proximity to the active circuit were evaluated. Based on HD 3D mapping, 27 circuits were observed: 12 peritricuspid, 2 upper loop reentry, 10 lower loop reentry, and 3 lateral wall circuits. With entrainment, 17 of the 27 circuits were active: all 12 peritricuspid and 2 upper loop reentry. However, lower loop reentry was confirmed in only 3 of 10, and none of the 3 lateral wall circuits were present. Mean percentage of tachycardia cycle length covered by active circuits was 98% ± 1% vs 97% ± 2% for passive circuits (P = .09). None of the 345 entrainment runs terminated tachycardia or changed tachycardia mechanism. In 8 of 15 patients, 13 examples of unexpectedly long postpacing interval were observed at entrainment sites located distal to localized zones of slow conduction seen on HD 3D mapping. Using HD 3D mapping, "visual reentry" may be due to passive circuitous propagation rather than a critical reentrant circuit. HD 3D mapping provides new insights into regional conduction and helps explain unusual entrainment phenomena. Copyright © 2017 Heart Rhythm Society. Published by Elsevier Inc. All rights reserved.

  17. Behavior of HfB2-SiC Materials in Simulated Re-Entry Environments

    Science.gov (United States)

    Ellerby, Don; Beckman, Sarah; Irby, Edward; Johnson, Sylvia M.; Gunsman, Michael; Gasch, Matthew; Ridge, Jerry; Martinez, Ed; Squire, Tom; Olejniczak, Joe

    2003-01-01

    The objectives of this research are to: 1) Investigate the oxidation/ablation behavior of HfB2/SiC materials in simulated re-entry environments; 2) Use the arc jet test results to define appropriate use environments for these materials for use in vehicle design. The parameters to be investigated include: surface temperature, stagnation pressure, duration, number of cycles, and thermal stresses.

  18. 78 FR 72011 - Interpretation Concerning Involvement of NASA Astronauts During a Licensed Launch or Reentry

    Science.gov (United States)

    2013-12-02

    ..., from engaging in operational functions during an FAA-licensed launch or reentry. NASA noted that all... environmental controls and life support systems.'' NASA also asked the FAA whether NASA's astronauts could... an off-nominal or emergency situation, the NASA astronaut would, much of the time, be using...

  19. Input shaping control with reentry commands of prescribed duration

    Directory of Open Access Journals (Sweden)

    Valášek M.

    2008-12-01

    Full Text Available Control of flexible mechanical structures often deals with the problem of unwanted vibration. The input shaping is a feedforward method based on modification of the input signal so that the output performs the demanded behaviour. The presented approach is based on a finite-time Laplace transform. It leads to no-vibration control signal without any limitations on its time duration because it is not strictly connected to the system resonant frequency. This idea used for synthesis of control input is extended to design of dynamical shaper with reentry property that transform an arbitrary input signal to the signal that cause no vibration. All these theoretical tasks are supported by the results of simulation experiments.

  20. Comparative risk analysis

    International Nuclear Information System (INIS)

    Niehaus, F.

    1988-01-01

    In this paper, the risks of various energy systems are discussed considering severe accidents analysis, particularly the probabilistic safety analysis, and probabilistic safety criteria, and the applications of these criteria and analysis. The comparative risk analysis has demonstrated that the largest source of risk in every society is from daily small accidents. Nevertheless, we have to be more concerned about severe accidents. The comparative risk analysis of five different energy systems (coal, oil, gas, LWR and STEC (Solar)) for the public has shown that the main sources of risks are coal and oil. The latest comparative risk study of various energy has been conducted in the USA and has revealed that the number of victims from coal is 42 as many than victims from nuclear. A study for severe accidents from hydro-dams in United States has estimated the probability of dam failures at 1 in 10,000 years and the number of victims between 11,000 and 260,000. The average occupational risk from coal is one fatal accident in 1,000 workers/year. The probabilistic safety analysis is a method that can be used to assess nuclear energy risks, and to analyze the severe accidents, and to model all possible accident sequences and consequences. The 'Fault tree' analysis is used to know the probability of failure of the different systems at each point of accident sequences and to calculate the probability of risks. After calculating the probability of failure, the criteria for judging the numerical results have to be developed, that is the quantitative and qualitative goals. To achieve these goals, several systems have been devised by various countries members of AIEA. The probabilistic safety ana-lysis method has been developed by establishing a computer program permit-ting to know different categories of safety related information. 19 tabs. (author)

  1. Foundations of Risk Analysis

    CERN Document Server

    Aven, Terje

    2012-01-01

    Foundations of Risk Analysis presents the issues core to risk analysis - understanding what risk means, expressing risk, building risk models, addressing uncertainty, and applying probability models to real problems. The author provides the readers with the knowledge and basic thinking they require to successfully manage risk and uncertainty to support decision making. This updated edition reflects recent developments on risk and uncertainty concepts, representations and treatment. New material in Foundations of Risk Analysis includes:An up to date presentation of how to understand, define and

  2. Probabilistic risk analysis and terrorism risk.

    Science.gov (United States)

    Ezell, Barry Charles; Bennett, Steven P; von Winterfeldt, Detlof; Sokolowski, John; Collins, Andrew J

    2010-04-01

    Since the terrorist attacks of September 11, 2001, and the subsequent establishment of the U.S. Department of Homeland Security (DHS), considerable efforts have been made to estimate the risks of terrorism and the cost effectiveness of security policies to reduce these risks. DHS, industry, and the academic risk analysis communities have all invested heavily in the development of tools and approaches that can assist decisionmakers in effectively allocating limited resources across the vast array of potential investments that could mitigate risks from terrorism and other threats to the homeland. Decisionmakers demand models, analyses, and decision support that are useful for this task and based on the state of the art. Since terrorism risk analysis is new, no single method is likely to meet this challenge. In this article we explore a number of existing and potential approaches for terrorism risk analysis, focusing particularly on recent discussions regarding the applicability of probabilistic and decision analytic approaches to bioterrorism risks and the Bioterrorism Risk Assessment methodology used by the DHS and criticized by the National Academies and others.

  3. MATHEMATICAL RISK ANALYSIS: VIA NICHOLAS RISK MODEL AND BAYESIAN ANALYSIS

    Directory of Open Access Journals (Sweden)

    Anass BAYAGA

    2010-07-01

    Full Text Available The objective of this second part of a two-phased study was to explorethe predictive power of quantitative risk analysis (QRA method andprocess within Higher Education Institution (HEI. The method and process investigated the use impact analysis via Nicholas risk model and Bayesian analysis, with a sample of hundred (100 risk analysts in a historically black South African University in the greater Eastern Cape Province.The first findings supported and confirmed previous literature (KingIII report, 2009: Nicholas and Steyn, 2008: Stoney, 2007: COSA, 2004 that there was a direct relationship between risk factor, its likelihood and impact, certiris paribus. The second finding in relation to either controlling the likelihood or the impact of occurrence of risk (Nicholas risk model was that to have a brighter risk reward, it was important to control the likelihood ofoccurrence of risks as compared with its impact so to have a direct effect on entire University. On the Bayesian analysis, thus third finding, the impact of risk should be predicted along three aspects. These aspects included the human impact (decisions made, the property impact (students and infrastructural based and the business impact. Lastly, the study revealed that although in most business cases, where as business cycles considerably vary dependingon the industry and or the institution, this study revealed that, most impacts in HEI (University was within the period of one academic.The recommendation was that application of quantitative risk analysisshould be related to current legislative framework that affects HEI.

  4. Effects of a reentry plasma sheath on the beam pointing properties of an array antenna

    Directory of Open Access Journals (Sweden)

    Bowen Bai

    2018-03-01

    Full Text Available The reduction in the gain of an on-board antenna caused by a reentry plasma sheath is an important effect that contributes to the reentry “blackout” problem. Using phased array antenna and beamforming technology could provide higher gain and an increase in the communication signal intensity. The attenuation and phase delay of the electromagnetic (EM waves transmitting through the plasma sheath are direction-dependent, and the radiation pattern of the phased array antenna is affected, leading to a deviation in the beam pointing. In this paper, the far-field pattern of a planar array antenna covered by a plasma sheath is deduced analytically by considering both refraction and mutual coupling effects. A comparison between the analytic results and the results from an electromagnetic simulation is carried out. The effect of the plasma sheath on the radiation pattern and the beam pointing errors of the phased array antenna is studied systematically, and the derived results could provide useful information for the correction of pointing errors.

  5. Comparing Black and White Drug Offenders: Implications for Racial Disparities in Criminal Justice and Reentry Policy and Programming.

    Science.gov (United States)

    Rosenberg, Alana; Groves, Allison K; Blankenship, Kim M

    2017-01-01

    Despite knowledge of racial bias for drug-related criminal justice involvement and its collateral consequences, we know less about differences between Black and White drug offenders. We compare 243 Blacks and White non-violent drug offenders in New Haven, CT for demographic characteristics, substance use, and re-entry services accessed. Blacks were significantly more likely to have sales and possession charges, significantly more likely to prefer marijuana, a less addictive drug, and significantly less likely to report having severe drug problems. For both races, drug treatment was the most common service accessed through supervision. These comparisons suggest different reasons for committing drug-related crimes and thus, different reentry programming needs. While drug treatment is critical for all who need it, for racial justice, we must also intervene to address other needs of offenders, such as poverty alleviation and employment opportunities.

  6. Nonlinear Transient Thermal Analysis by the Force-Derivative Method

    Science.gov (United States)

    Balakrishnan, Narayani V.; Hou, Gene

    1997-01-01

    High-speed vehicles such as the Space Shuttle Orbiter must withstand severe aerodynamic heating during reentry through the atmosphere. The Shuttle skin and substructure are constructed primarily of aluminum, which must be protected during reentry with a thermal protection system (TPS) from being overheated beyond the allowable temperature limit, so that the structural integrity is maintained for subsequent flights. High-temperature reusable surface insulation (HRSI), a popular choice of passive insulation system, typically absorbs the incoming radiative or convective heat at its surface and then re-radiates most of it to the atmosphere while conducting the smallest amount possible to the structure by virtue of its low diffusivity. In order to ensure a successful thermal performance of the Shuttle under a prescribed reentry flight profile, a preflight reentry heating thermal analysis of the Shuttle must be done. The surface temperature profile, the transient response of the HRSI interior, and the structural temperatures are all required to evaluate the functioning of the HRSI. Transient temperature distributions which identify the regions of high temperature gradients, are also required to compute the thermal loads for a structural thermal stress analysis. Furthermore, a nonlinear analysis is necessary to account for the temperature-dependent thermal properties of the HRSI as well as to model radiation losses.

  7. Active disturbance rejection attitude control for a hypersonic reentry vehicle with actuator saturation

    Directory of Open Access Journals (Sweden)

    Hongjiu Yang

    2017-05-01

    Full Text Available In this article, nonlinear uncertainty has been investigated for a hypersonic reentry vehicle subject to actuator saturation via active disturbance rejection control technology. A nonlinear extended state observer is designed to estimate “total disturbances,” which is compensated with a linear controller. Both convergence of the nonlinear extended state observer and stabilization of the closed-loop system are studied in this article. Some simulation results are given to illustrate the effectiveness of the proposed method.

  8. Is risk analysis scientific?

    Science.gov (United States)

    Hansson, Sven Ove; Aven, Terje

    2014-07-01

    This article discusses to what extent risk analysis is scientific in view of a set of commonly used definitions and criteria. We consider scientific knowledge to be characterized by its subject matter, its success in developing the best available knowledge in its fields of study, and the epistemic norms and values that guide scientific investigations. We proceed to assess the field of risk analysis according to these criteria. For this purpose, we use a model for risk analysis in which science is used as a base for decision making on risks, which covers the five elements evidence, knowledge base, broad risk evaluation, managerial review and judgment, and the decision; and that relates these elements to the domains experts and decisionmakers, and to the domains fact-based or value-based. We conclude that risk analysis is a scientific field of study, when understood as consisting primarily of (i) knowledge about risk-related phenomena, processes, events, etc., and (ii) concepts, theories, frameworks, approaches, principles, methods and models to understand, assess, characterize, communicate, and manage risk, in general and for specific applications (the instrumental part). © 2014 Society for Risk Analysis.

  9. Focal and Reentrant Mechanisms of Torsades de Pointes: EAD, Reentry, or Chimera?

    Directory of Open Access Journals (Sweden)

    Yuji Murakawa, MD

    2011-01-01

    Full Text Available Torsades de pointes (TdP. is characterized not only by its electrocardiographic morphology but also by a tendency to spontaneously terminate. Although clinical and experimental studies suggested that TdP is triggered exclusively by early afterdepolarization, the reentrant mechanism seems to play a certain role in its maintenance. In this article, I review the studies that investigated the origin and activation sequences of the twisting QRS complexes of TdP, and discuss whether it is fortunate or unfortunate for us if TdP has something to do with reentry.

  10. Environmental modeling and health risk analysis (ACTS/RISK)

    National Research Council Canada - National Science Library

    Aral, M. M

    2010-01-01

    ... presents a review of the topics of exposure and health risk analysis. The Analytical Contaminant Transport Analysis System (ACTS) and Health RISK Analysis (RISK) software tools are an integral part of the book and provide computational platforms for all the models discussed herein. The most recent versions of these two softwa...

  11. ARV Re-Entry Module Aerodynmics And Aerothermodynamics

    Science.gov (United States)

    Scheer, Heloise; Tran, Philippe; Berthe, Philippe

    2011-05-01

    Astrium-ST is the prime contractor of ARV phase A and is especially in charge of designing the Reentry Module (RM). The RM aeroshape has been defined following a trade-off. High level system requirements were derived with particular attention paid on minimum lift-over-drag ratio, trim incidence, centre-of-gravity lateral off-set and box size, volumetric efficiency, attitude at parachute deployment, flight heritage and aeroheating. Since moderate cross-range and thus L/D ratio were required, the aeroshape trade-off has been performed among blunt capsule candidates. Two front- shield families were considered: spherical (Apollo/ARD/Soyuz type) and sphero-conical (CTV type) segment front-shield. The rear-cone angle was set to 20° for internal pressurized volume and accommodation purposes. Figures of merit were assessed and a spherical front- shield of ARD type with a 20° rear-cone section was selected and proposed for further investigations. Maximum benefits will be taken from ARD flight heritage. CFD and WTT campaigns plans will be presented including preliminary results.

  12. Reentry Program and Social Work Education: Training the Next Generation of Criminal Justice Social Workers.

    Science.gov (United States)

    Franke, Nancy D; Treglia, Dan; Cnaan, Ram A

    2017-01-01

    Social work plays a marginal role in opposing the trend of mass incarceration and high rates of recidivism, and social work education offers limited opportunities for students to specialize in working with people who are currently or were previously incarcerated. How to train students of social work to work against mass-incarceration is still challenging. The authors devised and implemented an in-school social service agency devoted to working with people pre and post release from a prison system. The agency is a field practicum setting where interested students study and practice reentry work. In this article, the authors describe and assess the educational merit of this in-school agency. Findings from surveys of students and alumni suggest that the program attained its educational goals of connecting classroom education to practice experience and training students for careers in the criminal justice system. The authors also discuss pending challenges. The experience of the Goldring Reentry Initiative suggests that by developing their own social work agencies, the authors may be able to heighten their students educational experience and expand their contribution to social work practice broadly.

  13. Application of light-initiated explosive for simulating x-ray blowoff impulse effects on a full scale reentry vehicle

    International Nuclear Information System (INIS)

    Benham, R.A.; Mathews, F.H.; Higgins, P.B.

    1976-01-01

    Laboratory nuclear effects testing allows the study of reentry vehicle response to simulated exoatmospheric x-ray encounters. Light-initiated explosive produces the nearly simultaneous impulse loading of a structure by using a spray painted coating of explosive which is detonated by an intense flash of light. A lateral impulse test on a full scale reentry vehicle is described which demonstrates that the light-initiated explosive technique can be extended to the lateral loading of very large systems involving load discontinuities. This experiment required the development of a diagnostic method for verifying the applied impulse, and development of a large light source for simultaneously initiating the explosive over the surface of the vehicle. Acceptable comparison between measured strain response and code predictions is obtained. The structural capability and internal response of a vehicle subjected to an x-ray environment was determined from a light-initiated explosive test

  14. Uncontrolled re-entry of satellite parts after finishing their mission in LEO: Titanium alloy degradation by thermite reaction energy

    Science.gov (United States)

    Monogarov, K. A.; Pivkina, A. N.; Grishin, L. I.; Frolov, Yu. V.; Dilhan, D.

    2017-06-01

    Analytical and experimental studies conducted at Semenov Institute of Chemical Physics for investigating the use of pyrotechnic compositions, i.e., thermites, to reduce the risk of the fall of thermally stable parts of deorbiting end-of-life LEO satellites on the Earth are described. The main idea was the use of passive heating during uncontrolled re-entry to ignite thermite composition, fixed on the titanium surface, with the subsequent combustion energy release to be sufficient to perforate the titanium cover. It is supposed, that thus destructed satellite parts will lose their streamline shape, and will burn out being aerodynamically heated during further descending in atmosphere (patent FR2975080). On the base of thermodynamic calculations the most promising thermite compositions have been selected for the experimental phase. The unique test facilities have been developed for the testing of the efficiency of thermite charges to perforate the titanium TA6V cover of 0.8 mm thickness under temperature/pressure conditions duplicated the uncontrolled re-entry of titanium tank after its mission on LEO. Experiments with the programmed laser heating inside the vacuum chamber revealed the only efficient thermite composition among preliminary selected ones to be Al/Co3O4. Experimental searching of the optimal aluminum powder between spherical and flaked nano- and micron-sized ones revealed the possibility to adjust the necessary ignition delay time, according to the titanium cover temperature dependency on deorbiting time. For the titanium tank the maximum temperature is 1100 °C at altitude 68 km and pressure 60 Pa. Under these conditions Al/Co3O4 formulations with nano-Al spherical particles provide the ignition time to be 13.3 s, and ignition temperature as low as 592±5 °C, whereas compositions with the micron-sized spherical Al powder reveal these values to be much higher, i.e., 26.3 s and 869±5 °C, respectively. The analytical and experimental studies described

  15. ProRisk : risk analysis instrument : developed for William properties

    NARCIS (Netherlands)

    van Doorn, W.H.W.; Egeberg, Ingrid; Hendrickx, Kristoff; Kahramaner, Y.; Masseur, B.; Waijers, Koen; Weglicka, K.A.

    2005-01-01

    This report presents a Risk Analysis Instrument developed for William Properties. Based on the analysis, it appears that the practice of Risk Analysis exists within the organization, yet rather implicit. The Risk Analysis Instrument comes with a package of four components: an activity diagram, a

  16. Observations on risk analysis

    International Nuclear Information System (INIS)

    Thompson, W.A. Jr.

    1979-11-01

    This paper briefly describes WASH 1400 and the Lewis report. It attempts to define basic concepts such as risk and risk analysis, common mode failure, and rare event. Several probabilistic models which go beyond the WASH 1400 methodology are introduced; the common characteristic of these models is that they recognize explicitly that risk analysis is time dependent whereas WASH 1400 takes a per demand failure rate approach which obscures the important fact that accidents are time related. Further, the presentation of a realistic risk analysis should recognize that there are various risks which compete with one another for the lives of the individuals at risk. A way of doing this is suggested

  17. Space Flight and Re-Entry Trajectories : International Symposium

    CERN Document Server

    Libby, Paul A

    1962-01-01

    In this and a following issue (Vol. VIII, 1962, Fasc. 2-3) of "Astronautica Acta" there will appear the papers presented at the first international symposium sponsored by the International Academy of Astronautics of the International Astronautical Federation. The theme of the meeting was "Space Flight and Re-Entry Trajectories." It was held at Louveciennes outside of Paris on June 19-21, 1961. Sixteen papers by authors from nine countries were presented; attendees numbered from 80 to 100. The organizing committee for the symposium was as follows: Prof. PAUL A. LIBBY, Polytechnic Institute of Brooklyn, U.S.A., Chairman; Prof. LuiGI BROGLIO, University of Rome, Italy; Prof. B. FRAEIJS DE VEUBEKE, University of Liege, Belgium; Dr. D. G. KING-HELE, Royal Aircraft Establishment, Farnborough, Rants, United Kingdom; Prof. J. M. J. KooY, Royal Military School, Breda, Netherlands; Prof. JEAN KovALEVSKY, Bureau des Longitudes, Paris, France; Prof. RuDOLF PESEK, Academy of Sciences, Prague, Czechoslovakia. The detailed ...

  18. Atrial fibrillation driven by micro-anatomic intramural re-entry revealed by simultaneous sub-epicardial and sub-endocardial optical mapping in explanted human hearts.

    Science.gov (United States)

    Hansen, Brian J; Zhao, Jichao; Csepe, Thomas A; Moore, Brandon T; Li, Ning; Jayne, Laura A; Kalyanasundaram, Anuradha; Lim, Praise; Bratasz, Anna; Powell, Kimerly A; Simonetti, Orlando P; Higgins, Robert S D; Kilic, Ahmet; Mohler, Peter J; Janssen, Paul M L; Weiss, Raul; Hummel, John D; Fedorov, Vadim V

    2015-09-14

    The complex architecture of the human atria may create physical substrates for sustained re-entry to drive atrial fibrillation (AF). The existence of sustained, anatomically defined AF drivers in humans has been challenged partly due to the lack of simultaneous endocardial-epicardial (Endo-Epi) mapping coupled with high-resolution 3D structural imaging. Coronary-perfused human right atria from explanted diseased hearts (n = 8, 43-72 years old) were optically mapped simultaneously by three high-resolution CMOS cameras (two aligned Endo-Epi views (330 µm2 resolution) and one panoramic view). 3D gadolinium-enhanced magnetic resonance imaging (GE-MRI, 80 µm3 resolution) revealed the atrial wall structure varied in thickness (1.0 ± 0.7-6.8 ± 2.4 mm), transmural fiber angle differences, and interstitial fibrosis causing transmural activation delay from 23 ± 11 to 43 ± 22 ms at increased pacing rates. Sustained AF (>90 min) was induced by burst pacing during pinacidil (30-100 µM) perfusion. Dual-sided sub-Endo-sub-Epi optical mapping revealed that AF was driven by spatially and temporally stable intramural re-entry with 107 ± 50 ms cycle length and transmural activation delay of 67 ± 31 ms. Intramural re-entrant drivers were captured primarily by sub-Endo mapping, while sub-Epi mapping visualized re-entry or 'breakthrough' patterns. Re-entrant drivers were anchored on 3D micro-anatomic tracks (15.4 ± 2.2 × 6.0 ± 2.3 mm2, 2.9 ± 0.9 mm depth) formed by atrial musculature characterized by increased transmural fiber angle differences and interstitial fibrosis. Targeted radiofrequency ablation of the tracks verified these re-entries as drivers of AF. Integrated 3D structural-functional mapping of diseased human right atria ex vivo revealed that the complex atrial microstructure caused significant differences between Endo vs. Epi activation during pacing and sustained AF driven by intramural re-entry anchored to fibrosis-insulated atrial bundles. Published on

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

    Science.gov (United States)

    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.

  20. Unsharpness-risk analysis

    International Nuclear Information System (INIS)

    Preyssl, C.

    1986-01-01

    Safety analysis provides the only tool for evaluation and quantification of rare or hypothetical events leading to system failure. So far probability theory has been used for the fault- and event-tree methodology. The phenomenon of uncertainties constitutes an important aspect in risk analysis. Uncertainties can be classified as originating from 'randomness' or 'fuzziness'. Probability theory addresses randomness only. The use of 'fuzzy set theory' makes it possible to include both types of uncertainty in the mathematical model of risk analysis. Thus the 'fuzzy fault tree' is expressed in 'possibilistic' terms implying a range of simplifications and improvements. 'Human failure' and 'conditionality' can be treated correctly. Only minimum-maximum relations are used to combine the possibility distributions of events. Various event-classifications facilitate the interpretation of the results. The method is demonstrated by application to a TRIGA-research reactor. Uncertainty as an implicit part of 'fuzzy risk' can be quantified explicitly using an 'uncertainty measure'. Based on this the 'degree of relative compliance' with a quantizative safety goal can be defined for a particular risk. The introduction of 'weighting functionals' guarantees the consideration of the importances attached to different parts of the risk exceeding or complying with the standard. The comparison of two reference systems is demonstrated in a case study. It is concluded that any application of the 'fuzzy risk analysis' has to be free of any hypostatization when reducing subjective to objective information. (Author)

  1. A Qualitative Investigation of the College Choice Experiences and Reentry Expectations of U.S. American Third Culture Kids

    Science.gov (United States)

    Thurston-Gonzalez, Sara J.

    2009-01-01

    The focus of this qualitative study is on U.S. third culture kids (TCKs), youth who have grown up abroad because of their parent's work, and their college choice experiences and reentry expectations. Through a background questionnaire and personal interviews with eleven students transitioning from two international secondary schools in a…

  2. RAMS (Risk Analysis - Modular System) methodology

    Energy Technology Data Exchange (ETDEWEB)

    Stenner, R.D.; Strenge, D.L.; Buck, J.W. [and others

    1996-10-01

    The Risk Analysis - Modular System (RAMS) was developed to serve as a broad scope risk analysis tool for the Risk Assessment of the Hanford Mission (RAHM) studies. The RAHM element provides risk analysis support for Hanford Strategic Analysis and Mission Planning activities. The RAHM also provides risk analysis support for the Hanford 10-Year Plan development activities. The RAMS tool draws from a collection of specifically designed databases and modular risk analysis methodologies and models. RAMS is a flexible modular system that can be focused on targeted risk analysis needs. It is specifically designed to address risks associated with overall strategy, technical alternative, and `what if` questions regarding the Hanford cleanup mission. RAMS is set up to address both near-term and long-term risk issues. Consistency is very important for any comparative risk analysis, and RAMS is designed to efficiently and consistently compare risks and produce risk reduction estimates. There is a wide range of output information that can be generated by RAMS. These outputs can be detailed by individual contaminants, waste forms, transport pathways, exposure scenarios, individuals, populations, etc. However, they can also be in rolled-up form to support high-level strategy decisions.

  3. Risk analysis

    International Nuclear Information System (INIS)

    Baron, J.H.; Nunez McLeod, J.; Rivera, S.S.

    1997-01-01

    This book contains a selection of research works performed in the CEDIAC Institute (Cuyo National University) in the area of Risk Analysis, with specific orientations to the subjects of uncertainty and sensitivity studies, software reliability, severe accident modeling, etc. This volume presents important material for all those researches who want to have an insight in the risk analysis field, as a tool to solution several problems frequently found in the engineering and applied sciences field, as well as for the academic teachers who want to keep up to date, including the new developments and improvements continuously arising in this field [es

  4. A background risk analysis. Vol. 1

    International Nuclear Information System (INIS)

    Taylor, J.R.

    1979-01-01

    This 4-volumes report gives a background of ideas, principles, and examples which might be of use in developing practical methods for risk analysis. Some of the risk analysis techniques, described are somewhat experimental. The report is written in an introductory style, but where some point needs further justification or evaluation, this is given in the form of a chapter appendix. In this way, it is hoped that the report can serve two purposes, - as a basis for starting risk analysis work and as a basis for discussing effectiveness of risk analysis procedures. The report should be seen as a preliminary stage, prior to a program of industrial trials of risk analysis methods. Vol. 1 contains a short history of risk analysis, and chapters on risk, failures, errors and accidents, and general procedures for risk analysis. (BP)

  5. International Conference on Risk Analysis

    CERN Document Server

    Oliveira, Teresa; Rigas, Alexandros; Gulati, Sneh

    2015-01-01

    This book covers the latest results in the field of risk analysis. Presented topics include probabilistic models in cancer research, models and methods in longevity, epidemiology of cancer risk, engineering reliability and economical risk problems. The contributions of this volume originate from the 5th International Conference on Risk Analysis (ICRA 5). The conference brought together researchers and practitioners working in the field of risk analysis in order to present new theoretical and computational methods with applications in biology, environmental sciences, public health, economics and finance.

  6. Re-entry of the Soyuz MS-08 carrier rocket 25 March 2018

    Science.gov (United States)

    Stomeo, Enrico

    2018-03-01

    The re-entry of the Soyuz MS-08 carrier rocket on 2018 March 25 could be observed from a large part of the central Mediterranean Sea. The radio station of the Planetarium in Venice was able to record the return into the atmosphere. The radio signal was perceived in Venice from 01h23m52,5s UTC with a frequency of 1431,363 Hz until 01h24m02,0s with a frequency of 805,487 Hz. Considering the recorded frequency variations due to the Doppler effect, it can be deduced that the object was drastically decelerating in those last moments by about 1.3 km/s.

  7. Community reentry challenges after release from prison among people who inject drugs in St. Petersburg, Russia.

    Science.gov (United States)

    Cepeda, Javier A; Vetrova, Marina V; Lyubimova, Alexandra I; Levina, Olga S; Heimer, Robert; Niccolai, Linda M

    2015-01-01

    Little is known about the context of the post-release risk environment among formerly incarcerated people who inject drugs (PWID) in Russia. The purpose of this paper is to explore these challenges as they relate to reentry, relapse to injection opioid use, and overdose. The authors conducted 25 in-depth semi-structured interviews among PWID living in St Petersburg, Russia who had been incarcerated within the past two years. Participants were recruited from street outreach (n=20) and a drug treatment center (n=5). Emergent themes related to the post-release environment included financial instability, negative interactions with police, return to a drug using community, and reuniting with drug using peers. Many respondents relapsed to opioid use immediately after release. Those whose relapse occurred weeks or months after their release expressed more motivation to resist. Alcohol or stimulant use often preceded the opioid relapse episode. Among those who overdosed, alcohol use was often reported prior to overdosing on opioids. Future post-release interventions in Russia should effectively link PWID to social, medical, and harm reduction services. Particular attention should be focussed on helping former inmates find employment and overdose prevention training prior to leaving prison that should also cover the heightened risk of concomitant alcohol use. In addition to describing a syndemic involving the intersection of incarceration, injection drug use, poverty, and alcohol abuse, the findings can inform future interventions to address these interrelated public health challenges within the Russian setting.

  8. Does Offender Gambling on the inside Continue on the outside? Insights from Correctional Professionals on Gambling and Re-Entry

    Science.gov (United States)

    Williams, D. J.; Walker, Gordon J.

    2009-01-01

    This study brings to light a neglected topic of particular importance--offender gambling issues within the context of re-entry into the community. Fifteen correctional professionals from Nevada (high gambling availability) and Utah (no legalized gambling) participated in semi-structured interviews to provide insights into how gambling may impact…

  9. Risk analysis: opening the process

    International Nuclear Information System (INIS)

    Hubert, Ph.; Mays, C.

    1998-01-01

    This conference on risk analysis took place in Paris, 11-14 october 1999. Over 200 paper where presented in the seven following sessions: perception; environment and health; persuasive risks; objects and products; personal and collective involvement; assessment and valuation; management. A rational approach to risk analysis has been developed in the three last decades. Techniques for risk assessment have been thoroughly enhanced, risk management approaches have been developed, decision making processes have been clarified, the social dimensions of risk perception and management have been investigated. Nevertheless this construction is being challenged by recent events which reveal how deficits in stakeholder involvement, openness and democratic procedures can undermine risk management actions. Indeed, the global process most components of risk analysis may be radically called into question. Food safety has lately been a prominent issue, but now debates appear, or old debates are revisited in the domains of public health, consumer products safety, waste management, environmental risks, nuclear installations, automobile safety and pollution. To meet the growing pressures for efficiency, openness, accountability, and multi-partner communication in risk analysis, institutional changes are underway in many European countries. However, the need for stakeholders to develop better insight into the process may lead to an evolution of all the components of risks analysis, even in its most (technical' steps. For stakeholders of different professional background, political projects, and responsibilities, risk identification procedures must be rendered understandable, quantitative risk assessment must be intelligible and accommodated in action proposals, ranging from countermeasures to educational programs to insurance mechanisms. Management formats must be open to local and political input and other types of operational feedback. (authors)

  10. Adversarial risk analysis

    CERN Document Server

    Banks, David L; Rios Insua, David

    2015-01-01

    Flexible Models to Analyze Opponent Behavior A relatively new area of research, adversarial risk analysis (ARA) informs decision making when there are intelligent opponents and uncertain outcomes. Adversarial Risk Analysis develops methods for allocating defensive or offensive resources against intelligent adversaries. Many examples throughout illustrate the application of the ARA approach to a variety of games and strategic situations. The book shows decision makers how to build Bayesian models for the strategic calculation of their opponents, enabling decision makers to maximize their expected utility or minimize their expected loss. This new approach to risk analysis asserts that analysts should use Bayesian thinking to describe their beliefs about an opponent's goals, resources, optimism, and type of strategic calculation, such as minimax and level-k thinking. Within that framework, analysts then solve the problem from the perspective of the opponent while placing subjective probability distributions on a...

  11. Vocational Interest as a Correlate of Re-Entry of Girls into School in Edo State, Nigeria: Implications for Counselling

    Science.gov (United States)

    Alika, Ijeoma Henrietta; Egbochuku, Elizabeth Omotunde

    2012-01-01

    The study investigated the relationship between vocational interest socio-economic status and re-entry of girls into school in Edo State. The research design adopted was correlational because it sought to establish the relationship between the independent variable and the dependent variable. A sample size of 306 girls who re-enrolled in institutes…

  12. An Exploration of Factors Reducing Recidivism Rates of Formerly Incarcerated Youth with Disabilities Participating in a Re-Entry Intervention

    Science.gov (United States)

    Unruh, Deanne K.; Gau, Jeff M.; Waintrup, Miriam G.

    2009-01-01

    Juvenile offenders are costly to our society in terms of the monetary and social expenditures from the legal system, victims' person costs, and incarceration. The re-entry and community reintegration outcomes for formerly incarcerated youth with a disabling condition are bleak compared to peers without disabilities. In this study, we examined the…

  13. A FMM-FFT accelerated hybrid volume surface integral equation solver for electromagnetic analysis of re-entry space vehicles

    KAUST Repository

    Yücel, Abdulkadir C.

    2014-07-01

    Space vehicles that re-enter the atmosphere often experience communication blackout. The blackout occurs when the vehicle becomes engulfed in plasma produced by interactions between the vehicle surface and the atmosphere. The plasma often is concentrated in a relatively thin shell around the vehicle, with higher densities near its nose than rear. A less structured, sometimes turbulent plasma wake often trails the vehicle. The plasma shell severely affects the performance of side-mounted antennas as it alters their characteristics (frequency response, gain patterns, axial ratio, and impedance) away from nominal, free-space values, sometimes entirely shielding the antenna from the outside world. The plasma plume/turbulent wake similarly affect the performance of antennas mounted at the back of the vehicle. The electromagnetic characteristics of the thin plasma shell and plume/turbulent wake heavily depend on the type of re-entry trajectory, the vehicle\\'s speed, angles of attack, and chemical composition, as well as environmental conditions. To analyze the antennas\\' performance during blackout and to design robust communication antennas, efficient and accurate simulation tools for charactering the antennas\\' performance along the trajectory are called for.

  14. Factors associated with dropout among patients in opioid maintenance treatment (OMT) and predictors of re-entry. A national registry-based study.

    Science.gov (United States)

    Bukten, Anne; Skurtveit, Svetlana; Waal, Helge; Clausen, Thomas

    2014-10-01

    Retention in treatment is often highlighted as one of the key indicators of success in opioid maintenance treatment (OMT). To identify factors associated with long-term retention in opioid maintenance treatment and to analyse predictors of subsequent treatment episodes. Treatment retention and re-entry were examined for a national cohort of patients admitted to OMT in Norway in the period 1997-2003. Multivariate Cox regression models were used to investigate factors associated with treatment dropout 18months after treatment entry. The 18month retention rate among patients admitted to OMT in Norway (n=2431) was 65.8% (n=1599). Dropout from OMT within 18months was associated with younger age (HR 0.97 [0.96-0.98]), high levels of general pre-treatment criminal offences (HR 1.66 [1.32-2.09]) and having drug-related offences during the 30days prior to dropout (HR 1.80 [1.36-2.38]). Of the patients who dropped out (n=832), 42.7% (n=355) were re-engaged in subsequent treatment episodes. Pre-treatment criminal offences were associated with increased odds for treatment re-entry, whereas being younger and having drug-related offences during the first OMT episode were associated with lower odds for re-engagement in OMT. Gender was not associated with treatment dropout and re-entry. High levels of pre-treatment criminal offences and drug offences during the 30days prior to dropout were associated with treatment dropout. Efforts to increase support services to these patients may contribute to higher rates of retention in OMT. Copyright © 2014 Elsevier Ltd. All rights reserved.

  15. A background to risk analysis. Vol. 3

    International Nuclear Information System (INIS)

    Taylor, J.R.

    1979-01-01

    This 4-volumes report gives a background of ideas, principles, and examples which might be of use in developing practical methods for risk analysis. Some of the risk analysis techniques described are somewhat experimental. The report is written in an introductory style, but where some point needs further justifi- cation or evaluation, this is given in the form of a chapter appenix. In this way, it is hoped that the report can serve two purposes, - as a basis for starting risk analysis work and as a basis for discussing effectiveness of risk analysis procedures. The report should be seen as a preliminary stage, prior to a program of industrial trials of risk analysis methods. Vol. 3 contains chapters on quantification of risk, failure and accident probability, risk analysis and design, and examles of risk analysis for process plant. (BP)

  16. Retrograde transdorsal-to-plantar or transplantar-to-dorsal intraluminal re-entry treatment following unsuccessful subintimal angioplasty for below-the-ankle arterial occlusion

    International Nuclear Information System (INIS)

    Zhu Yueqi; Zhao Jungong; Li Minghua; Tan Huaqiao; Wang Jianbo; Liu Fang; Cheng Yingsheng; Wang Jue; Cheng Yongde

    2011-01-01

    Objective: To assess the technical feasibility and efficacy of transdorsal-to-plantar (TDP) or transplantar-to-dorsal (TPD) intraluminal re-entry procedure following unsuccessful subintimal angioplasty for the treatment of arterial occlusion below the ankle. Methods: TDP or TPD retrograde intraluminal re-entry angioplasty was carried out in 8 diseased limbs of 8 diabetic patients (5 males and 3 females, aged 62∼81 years with a mean age of 75±8 years), who were accompanied with chronic below-the-ankle arterial occlusive disease, after the standard transtibial subintimal angioplasty had failed. Both before and after the procedure the clinical symptoms, dorsal or plantar arterial pulse volume scores and ankle-brachial indexes (ABI) were determined in all patients, the results were compared and statistically analysed. During the follow-up period, the degree of pain relief, the healing of the wound, the salvage of the diseased limb and the restenosis occurrence of the target vessels were evaluated. Results: Of the total 8 patients, TDP or TPD retrograde intraluminal re-entry angioplasty was successfully performed in 5(62.5%). After the treatment the foot pain was markedly relieved, the median pulse volume scores and ankle-brachial indexes were increased from 0.60±0.55 and 0.32±0.20 before the procedure to 2.40±0.55 and 0.75±0.12 after the procedure, respectively (P<0.01 for both). At the end of the follow-up lasting for twelve months, the visual analogue scale was apparently improved, the scores decreased from preoperative 7.40±1.14 to 2.20±1.48 (P=0.002). Of two cases with intractable skin ulcer, the skin lesion was completely healed in one and was significantly decreased in size in another. No amputation surgery was needed in all successfully treated patients. Magnetic resonance angiography revealed that one target vessel developed re-stenosis. Conclusion: TDP and TDP retrograde intraluminal re-entry techniques are clinically feasible and effective for the

  17. Environmental risk analysis

    International Nuclear Information System (INIS)

    Lima-e-Silva, Pedro Paulo de

    1996-01-01

    The conventional Risk Analysis (RA) relates usually a certain undesired event frequency with its consequences. Such technique is used nowadays in Brazil to analyze accidents and their consequences strictly under the human approach, valuing loss of human equipment, human structures and human lives, without considering the damage caused to natural resources that keep life possible on Earth. This paradigm was developed primarily because of the Homo sapiens' lack of perception upon the natural web needed to sustain his own life. In reality, the Brazilian professionals responsible today for licensing, auditing and inspecting environmental aspects of human activities face huge difficulties in making technical specifications and procedures leading to acceptable levels of impact, furthermore considering the intrinsic difficulties to define those levels. Therefore, in Brazil the RA technique is a weak tool for licensing for many reasons, and of them are its short scope (only accident considerations) and wrong a paradigm (only human direct damages). A paper from the author about the former was already proposed to the 7th International Conference on Environmetrics, past July'96, USP-SP. This one discusses the extension of the risk analysis concept to take into account environmental consequences, transforming the conventional analysis into a broader methodology named here as Environmental Risk Analysis. (author)

  18. INTERMITTENT ANTIARYTHMIC THERAPY OF ARIOVENTICULAR NODAL REENTRY TACHYCARDIA IN CHILDREN

    Directory of Open Access Journals (Sweden)

    Boris Djindjic

    2008-04-01

    Full Text Available Until recent advances in pharmacology and clinical cardiology regarding farmacodynamics of antiarrhythmic drugs and their efficiency in patients with refractory paroxysmal supraventricular tachycardia, chronic prophylactic therapy was the only treatment option for patients refusing catheter ablation. Another treatment option, also known by eponym “pill in pocket” have been shown to be equally useful and efficacious.The aim of our study was prospective examination of children with refractory atrioventricular nodal reentry tachycardia (AVNRT who were withdrawn from chronic antiarrhythmic prophylactic therapy and started with intermittent oral beta blocker treatment (propranolol at dosage 1 mg/kg - max 80 mg.Twelve children (8 boys and 4 girls with AVNRT were included in the study. Four children did not have arrhythmia during first six months after withdrawal and 7 were successfully treated without complication.Intermittent antiarrhythmic therapy in children with AVNRT could be very efficacious and useful treatment option which significantly improves their quality of life.

  19. Pre-flight physical simulation test of HIMES reentry test vehicle

    Science.gov (United States)

    Kawaguchi, Jun'ichiro; Inatani, Yoshifumi; Yonemoto, Koichi; Hosokawa, Shigeru

    ISAS is now developing a small reentry test vehicle, which is 2m long with a 1.5m wing span and weighs about 170 kg, for the purpose of exploring high angle-of-attack aerodynamic attitude control issue in supersonic and hypersonic speed. The flight test, employing 'Rockoon' launch system, is planned as a preliminary design verification for a fully reusable winged rocket named HIMES (Highly Maneuverable Experimental Space) vehicle. This paper describes the results of preflight ground test using a motion table system. This ground system test is called 'physical simulation' aimed at: (1) functional verification of side-jet system, aerodynamic surface actuators, battery and onboard avionics; and (2) guidance and control law evaluation, in total hardware-in-the-loop system. The pressure of side-jet nozzles was measured to provide exact thrust characteristics of reaction control. The dynamics of vehicle motion was calculated in real-time by the ground simulation computer.

  20. Component of the risk analysis

    International Nuclear Information System (INIS)

    Martinez, I.; Campon, G.

    2013-01-01

    The power point presentation reviews issues like analysis of risk (Codex), management risk, preliminary activities manager, relationship between government and industries, microbiological danger and communication of risk

  1. Credit Risk Evaluation : Modeling - Analysis - Management

    OpenAIRE

    Wehrspohn, Uwe

    2002-01-01

    An analysis and further development of the building blocks of modern credit risk management: -Definitions of default -Estimation of default probabilities -Exposures -Recovery Rates -Pricing -Concepts of portfolio dependence -Time horizons for risk calculations -Quantification of portfolio risk -Estimation of risk measures -Portfolio analysis and portfolio improvement -Evaluation and comparison of credit risk models -Analytic portfolio loss distributions The thesis contributes to the evaluatio...

  2. A nuclear source term analysis for spacecraft power systems

    International Nuclear Information System (INIS)

    McCulloch, W.H.

    1998-01-01

    All US space missions involving on board nuclear material must be approved by the Office of the President. To be approved the mission and the hardware systems must undergo evaluations of the associated nuclear health and safety risk. One part of these evaluations is the characterization of the source terms, i.e., the estimate of the amount, physical form, and location of nuclear material, which might be released into the environment in the event of credible accidents. This paper presents a brief overview of the source term analysis by the Interagency Nuclear Safety Review Panel for the NASA Cassini Space Mission launched in October 1997. Included is a description of the Energy Interaction Model, an innovative approach to the analysis of potential releases from high velocity impacts resulting from launch aborts and reentries

  3. Risk Analysis in Road Tunnels – Most Important Risk Indicators

    DEFF Research Database (Denmark)

    Berchtold, Florian; Knaust, Christian; Thöns, Sebastian

    2016-01-01

    Methodologies on fire risk analysis in road tunnels consider numerous factors affecting risks (risk indicators) and express the results by risk measures. But only few comprehensive studies on effects of risk indicators on risk measures are available. For this reason, this study quantifies...... the effects and highlights the most important risk indicators with the aim to support further developments in risk analysis. Therefore, a system model of a road tunnel was developed to determine the risk measures. The system model can be divided into three parts: the fire part connected to the fire model Fire...... Dynamics Simulator (FDS); the evacuation part connected to the evacuation model FDS+Evac; and the frequency part connected to a model to calculate the frequency of fires. This study shows that the parts of the system model (and their most important risk indicators) affect the risk measures in the following...

  4. Risk analysis in radiosurgery treatments using risk matrices

    International Nuclear Information System (INIS)

    Delgado, J. M.; Sanchez Cayela, C.; Ramirez, M. L.; Perez, A.

    2011-01-01

    The aim of this study is the risk analysis process stereotactic single-dose radiotherapy and evaluation of those initiating events that lead to increased risk and a possible solution in the design of barriers.

  5. Risk analysis of Odelouca cofferdam

    OpenAIRE

    Pimenta, L.; Caldeira, L.; Maranha das Neves, E.

    2009-01-01

    In this paper we present the risk analysis of Odelouca Cofferdam, using an event tree analysis. The initializing events, failure modes and analysed limit states are discussed based on an influence diagram. The constructed event trees and their interpretation are presented. The obtained risk values are represented in an FN plot superimposed to the acceptability and tolerability risk limits proposed for Portuguese dams. Initially, particular emphasis is placed on the main characteristic...

  6. 14 CFR 431.35 - Acceptable reusable launch vehicle mission risk.

    Science.gov (United States)

    2010-01-01

    ... applicable, and reentry or descent flight, and concludes upon landing on Earth of the RLV. (b) Acceptable... reentry or descent of the vehicle through landing, including its three-sigma dispersion. [Docket No. FAA...

  7. Generalized indices for radiation risk analysis

    International Nuclear Information System (INIS)

    Bykov, A.A.; Demin, V.F.

    1989-01-01

    A new approach to ensuring nuclear safety has begun forming since the early eighties. The approach based on the probabilistic safety analysis, the principles of acceptable risk, the optimization of safety measures, etc. has forced a complex of adequate quantitative methods of assessment, safety analysis and risk management to be developed. The method of radiation risk assessment and analysis hold a prominent place in the complex. National and international research and regulatory organizations ICRP, IAEA, WHO, UNSCEAR, OECD/NEA have given much attention to the development of the conceptual and methodological basis of those methods. Some resolutions of the National Commission of Radiological Protection (NCRP) and the Problem Commission on Radiation Hygiene of the USSR Ministry of Health should be also noted. Both CBA (cost benefit analysis) and other methods of radiation risk analysis and safety management use a system of natural and socio-economic indices characterizing the radiation risk or damage. There exist a number of problems associated with the introduction, justification and use of these indices. For example, the price, a, of radiation damage, or collective dose unit, is a noteworthy index. The difficulties in its qualitative and quantitative determination are still an obstacle for a wide application of CBA to the radiation risk analysis and management. During recent 10-15 years these problems have been a subject of consideration for many authors. The present paper also considers the issues of the qualitative and quantitative justification of the indices of radiation risk analysis

  8. A Novel Fenestration Technique for Abdominal Aortic Dissection Membranes Using a Combination of a Needle Re-entry Catheter and the “Cheese-wire” Technique

    International Nuclear Information System (INIS)

    Kos, Sebastian; Gürke, Lorenz; Jacob, Augustinus L.

    2011-01-01

    Purpose: This study was designed to demonstrate the applicability of a combined needle-based re-entry catheter and “cheese-wire” technique for fenestration of abdominal aortic dissection membranes. Methods: Four male patients (mean age: 65 years) with acute complicated aortic type B dissections were treated at our institution by fenestrating the abdominal aortic dissection membrane using a hybrid technique. This technique combined an initial membrane puncture with a needle-based re-entry catheter using a transfemoral approach. A guidewire was passed through the re-entry catheter and across the membrane. Using a contralateral transfemoral access, this guidewire was then snared, creating a through-and-through wire access. The membrane was then fenestrated using the cheese-wire maneuver. Results: We successfully performed: (a) membrane puncture; (b) guidewire passage; (c) guidewire snaring; and (d) cheese-wire maneuver in all four cases. After this maneuver, decompression of the false lumen and acceptable arterial inflow into the true lumen was observed in all cases. The dependent visceral arteries were reperfused. In one case, portions of the fenestrated membrane occluded the common iliac artery, which was immediately and successfully stented. In another case, long-standing intestinal hypoperfusion before the fenestration resulted in reperfusion-related shock and intraoperative death of the patient. Conclusions: The described hybrid approach for fenestration of dissection membranes is technically feasible and may be established as a therapeutic method in cases with a complicated type B dissection.

  9. Reliability and validity of risk analysis

    International Nuclear Information System (INIS)

    Aven, Terje; Heide, Bjornar

    2009-01-01

    In this paper we investigate to what extent risk analysis meets the scientific quality requirements of reliability and validity. We distinguish between two types of approaches within risk analysis, relative frequency-based approaches and Bayesian approaches. The former category includes both traditional statistical inference methods and the so-called probability of frequency approach. Depending on the risk analysis approach, the aim of the analysis is different, the results are presented in different ways and consequently the meaning of the concepts reliability and validity are not the same.

  10. Safety analysis, risk assessment, and risk acceptance criteria

    International Nuclear Information System (INIS)

    Jamali, K.

    1997-01-01

    This paper discusses a number of topics that relate safety analysis as documented in the Department of Energy (DOE) safety analysis reports (SARs), probabilistic risk assessments (PRA) as characterized primarily in the context of the techniques that have assumed some level of formality in commercial nuclear power plant applications, and risk acceptance criteria as an outgrowth of PRA applications. DOE SARs of interest are those that are prepared for DOE facilities under DOE Order 5480.23 and the implementing guidance in DOE STD-3009-94. It must be noted that the primary area of application for DOE STD-3009 is existing DOE facilities and that certain modifications of the STD-3009 approach are necessary in SARs for new facilities. Moreover, it is the hazard analysis (HA) and accident analysis (AA) portions of these SARs that are relevant to the present discussions. Although PRAs can be qualitative in nature, PRA as used in this paper refers more generally to all quantitative risk assessments and their underlying methods. HA as used in this paper refers more generally to all qualitative risk assessments and their underlying methods that have been in use in hazardous facilities other than nuclear power plants. This discussion includes both quantitative and qualitative risk assessment methods. PRA has been used, improved, developed, and refined since the Reactor Safety Study (WASH-1400) was published in 1975 by the Nuclear Regulatory Commission (NRC). Much debate has ensued since WASH-1400 on exactly what the role of PRA should be in plant design, reactor licensing, 'ensuring' plant and process safety, and a large number of other decisions that must be made for potentially hazardous activities. Of particular interest in this area is whether the risks quantified using PRA should be compared with numerical risk acceptance criteria (RACs) to determine whether a facility is 'safe.' Use of RACs requires quantitative estimates of consequence frequency and magnitude

  11. A background to risk analysis. Vol. 2

    International Nuclear Information System (INIS)

    Taylor, J.R.

    1979-01-01

    This 4-volumes report gives a background of ideas, principles and examples which might be of use in developing practical methods for risk analysis. Some of the risk analysis techniques described are somewhat experimental. The report is written in an introductory style, but where some point needs further justification or evaluation, this is given in the form of a chapter appendix. In this way, it is hoped that the report can serve two purposes, - as a basis for starting risk analysis work and as a basis for discussing effectiveness of risk analysis procedures. The report should be seen as a preliminary stage, prior to a program of industrial trials of risk analysis methods. Vol. 2 treats generic methods of qualitative failure analysis. (BP)

  12. Information Security Risk Analysis

    CERN Document Server

    Peltier, Thomas R

    2010-01-01

    Offers readers with the knowledge and the skill-set needed to achieve a highly effective risk analysis assessment. This title demonstrates how to identify threats and then determine if those threats pose a real risk. It is suitable for industry and academia professionals.

  13. Bias in risk-benefit analysis

    International Nuclear Information System (INIS)

    Mazur, A.

    1985-01-01

    Risk-benefit analysis has become popular in the past decade as a means of improving decision making, especially in the area of technology policy. Here risk-benefit analysis is compared to other (equally defensible) approaches to decision making, showing how it favors some political interests more than others, and suggesting why it has recently come to the fore as a tool of political analysis. A considerable portion of the discussion concerns nuclear power. 6 references

  14. A background to risk analysis. Vol. 4

    International Nuclear Information System (INIS)

    Taylor, J.R.

    1979-01-01

    This 4-volumes report gives a background of ideas, principles, and examples which might be of use in developing practical methods for risk analysis. Some of the risk analysis techniques described are somewhat experimental. The report is written in an introductory style, but where some point needs further justification or evaluation, this is given in the form of a chapter appendix. In this way, it is hoped that the report can serve two purposes, - as a basis for starting risk analysis work and as a basis for discussing effectiveness of risk analysis procedures. The report should be seen as a preliminary stage, prior to a program of industrial trials of risk analysis methods. Vol. 4 treats human error in plant operation. (BP)

  15. Advances in probabilistic risk analysis

    International Nuclear Information System (INIS)

    Hardung von Hardung, H.

    1982-01-01

    Probabilistic risk analysis can now look back upon almost a quarter century of intensive development. The early studies, whose methods and results are still referred to occasionally, however, only permitted rough estimates to be made of the probabilities of recognizable accident scenarios, failing to provide a method which could have served as a reference base in calculating the overall risk associated with nuclear power plants. The first truly solid attempt was the Rasmussen Study and, partly based on it, the German Risk Study. In those studies, probabilistic risk analysis has been given a much more precise basis. However, new methodologies have been developed in the meantime, which allow much more informative risk studies to be carried out. They have been found to be valuable tools for management decisions with respect to backfitting, reinforcement and risk limitation. Today they are mainly applied by specialized private consultants and have already found widespread application especially in the USA. (orig.) [de

  16. WIPP fire hazards and risk analysis

    International Nuclear Information System (INIS)

    1991-05-01

    The purpose of this analysis was to conduct a fire hazards risk analysis of the Transuranic (TRU) contact-handled waste receipt, emplacement, and disposal activities at the Waste Isolation Pilot Plant (WIPP). The technical bases and safety envelope for these operations are defined in the approved WIPP Final Safety Analysis Report (FSAR). Although the safety documentation for the initial phase of the Test Program, the dry bin scale tests, has not yet been approved by the Department of Energy (DOE), reviews of the draft to date, including those by the Advisory Committee on Nuclear Facility Safety (ACNFS), have concluded that the dry bin scale tests present no significant risks in excess of those estimated in the approved WIPP FSAR. It is the opinion of the authors and reviewers of this analysis, based on sound engineering judgment and knowledge of the WIPP operations, that a Fire Hazards and Risk Analysis specific to the dry bin scale test program is not warranted prior to first waste receipt. This conclusion is further supported by the risk analysis presented in this document which demonstrates the level of risk to WIPP operations posed by fire to be extremely low. 15 refs., 41 figs., 48 tabs

  17. The latent rationality of risky decisions

    Energy Technology Data Exchange (ETDEWEB)

    Japp, K.P. [Bielefeld Univ. (Germany). Faculty for Sociology

    1999-12-01

    The general question of rationality has changed from the old-fashioned difference of means and ends to the modern difference of system and environment. Organizations as social systems producing and reproducing decisions translate this difference into the difference of stability and variety. The question then is: In which way can the difference between stability and variety express rationality? - In the temporal dimension of risk-taking, re-entries may be expressed as 'present futures' or 'future presences'. These expressions indicate both: The irresolvable uncertainty of any risk-taking, indicated by open futures, and its boundedness by self-application of distinctions, e.g. projected futures from the background of a known past. - In the material dimension of risk-taking, re-entries may be expressed as 'stable flexibility' or 'flexible stability'. Again, these expressions indicate both: The irresolvable uncertainty of any risk-taking, indicted by open flexibilities, and its boundedness by self-application of distinctions, e.g. flexibility and stability after learning the respective costs of the single options. In the social dimension of risk-taking, re-entries may be expressed as 'pragmatic dissent' or 'controversial pragmatism'. Again, these expressions indicate both: The irresolvable uncertainty of any risk-taking, indicated by open dissent or controversies, and its boundedness by self-application of distinctions, e.g. pragmatic agreements and irresolvable dissent. Again, all three asymmetries represent re-entries. The built-in preferences simply do not work without the subtleties of re-entries, at least when these processes are described by sociologically informed observers. Who else should know that he or she is operating on the basis of something called re-entries? In everyday life communication, no one sees a thing like that since every observation has an in-built bias for one side of a distinction

  18. The latent rationality of risky decisions

    International Nuclear Information System (INIS)

    Japp, K.P.

    1999-01-01

    The general question of rationality has changed from the old-fashioned difference of means and ends to the modern difference of system and environment. Organizations as social systems producing and reproducing decisions translate this difference into the difference of stability and variety. The question then is: In which way can the difference between stability and variety express rationality? - In the temporal dimension of risk-taking, re-entries may be expressed as 'present futures' or 'future presences'. These expressions indicate both: The irresolvable uncertainty of any risk-taking, indicated by open futures, and its boundedness by self-application of distinctions, e.g. projected futures from the background of a known past. - In the material dimension of risk-taking, re-entries may be expressed as 'stable flexibility' or 'flexible stability'. Again, these expressions indicate both: The irresolvable uncertainty of any risk-taking, indicted by open flexibilities, and its boundedness by self-application of distinctions, e.g. flexibility and stability after learning the respective costs of the single options. In the social dimension of risk-taking, re-entries may be expressed as 'pragmatic dissent' or 'controversial pragmatism'. Again, these expressions indicate both: The irresolvable uncertainty of any risk-taking, indicated by open dissent or controversies, and its boundedness by self-application of distinctions, e.g. pragmatic agreements and irresolvable dissent. Again, all three asymmetries represent re-entries. The built-in preferences simply do not work without the subtleties of re-entries, at least when these processes are described by sociologically informed observers. Who else should know that he or she is operating on the basis of something called re-entries? In everyday life communication, no one sees a thing like that since every observation has an in-built bias for one side of a distinction. So rationality will stay latent as the operation of re-entry

  19. Risk Characterization uncertainties associated description, sensitivity analysis

    International Nuclear Information System (INIS)

    Carrillo, M.; Tovar, M.; Alvarez, J.; Arraez, M.; Hordziejewicz, I.; Loreto, I.

    2013-01-01

    The power point presentation is about risks to the estimated levels of exposure, uncertainty and variability in the analysis, sensitivity analysis, risks from exposure to multiple substances, formulation of guidelines for carcinogenic and genotoxic compounds and risk subpopulations

  20. Advances in Risk Analysis with Big Data.

    Science.gov (United States)

    Choi, Tsan-Ming; Lambert, James H

    2017-08-01

    With cloud computing, Internet-of-things, wireless sensors, social media, fast storage and retrieval, etc., organizations and enterprises have access to unprecedented amounts and varieties of data. Current risk analysis methodology and applications are experiencing related advances and breakthroughs. For example, highway operations data are readily available, and making use of them reduces risks of traffic crashes and travel delays. Massive data of financial and enterprise systems support decision making under risk by individuals, industries, regulators, etc. In this introductory article, we first discuss the meaning of big data for risk analysis. We then examine recent advances in risk analysis with big data in several topic areas. For each area, we identify and introduce the relevant articles that are featured in the special issue. We conclude with a discussion on future research opportunities. © 2017 Society for Risk Analysis.

  1. Overcoming barriers to integrating economic analysis into risk assessment.

    Science.gov (United States)

    Hoffmann, Sandra

    2011-09-01

    Regulatory risk analysis is designed to provide decisionmakers with a clearer understanding of how policies are likely to affect risk. The systems that produce risk are biological, physical, and social and economic. As a result, risk analysis is an inherently interdisciplinary task. Yet in practice, risk analysis has been interdisciplinary in only limited ways. Risk analysis could provide more accurate assessments of risk if there were better integration of economics and other social sciences into risk assessment itself. This essay examines how discussions about risk analysis policy have influenced the roles of various disciplines in risk analysis. It explores ways in which integrated bio/physical-economic modeling could contribute to more accurate assessments of risk. It reviews examples of the kind of integrated economics-bio/physical modeling that could be used to enhance risk assessment. The essay ends with a discussion of institutional barriers to greater integration of economic modeling into risk assessment and provides suggestions on how these might be overcome. © 2011 Society for Risk Analysis.

  2. Maritime transportation risk analysis: Review and analysis in light of some foundational issues

    International Nuclear Information System (INIS)

    Goerlandt, Floris; Montewka, Jakub

    2015-01-01

    Many methods and applications for maritime transportation risk analysis have been presented in the literature. In parallel, there is a recent focus on foundational issues in risk analysis, with calls for intensified research on fundamental concepts and principles underlying the scientific field. This paper presents a review and analysis of risk definitions, perspectives and scientific approaches to risk analysis found in the maritime transportation application area, focusing on applications addressing accidental risk of shipping in a sea area. For this purpose, a classification of risk definitions, an overview of elements in risk perspectives and a classification of approaches to risk analysis science are applied. Results reveal that in the application area, risk is strongly tied to probability, both in definitions and perspectives, while alternative views exist. A diffuse situation is also found concerning the scientific approach to risk analysis, with realist, proceduralist and constructivist foundations co-existing. Realist approaches dominate the application area. Very few applications systematically account for uncertainty, neither concerning the evidence base nor in relation to the limitations of the risk model in relation to the space of possible outcomes. Some suggestions are made to improve the current situation, aiming to strengthen the scientific basis for risk analysis. - Highlights: • Risk analyses in maritime transportation analysed in light of foundational issues. • Focus on definitions, perspectives and scientific approaches to risk analysis. • Probability-based definitions and realist approaches dominate the field. • Findings support calls for increased focus on foundational issues in risk research. • Some suggestions are made to improve the current situation

  3. STOCHASTIC METHODS IN RISK ANALYSIS

    Directory of Open Access Journals (Sweden)

    Vladimíra OSADSKÁ

    2017-06-01

    Full Text Available In this paper, we review basic stochastic methods which can be used to extend state-of-the-art deterministic analytical methods for risk analysis. We can conclude that the standard deterministic analytical methods highly depend on the practical experience and knowledge of the evaluator and therefore, the stochastic methods should be introduced. The new risk analysis methods should consider the uncertainties in input values. We present how large is the impact on the results of the analysis solving practical example of FMECA with uncertainties modelled using Monte Carlo sampling.

  4. Risk Analysis of Telecom Enterprise Financing

    Institute of Scientific and Technical Information of China (English)

    YU Hua; SHU Hua-ying

    2005-01-01

    The main research objects in this paper are the causes searching and risk estimating method for telecom enterprises' financial risks. The multi-mode financing for telecom enterprises makes it flexible to induce the capital and obtain the profit by corresponding projects. But there are also potential risks going with these financing modes. After making analysis of categories and causes of telecom enterprises' financing risk, a method by Analytic Hierarchy Process (AHP) is put forward to estimating the financing risk. And the author makes her suggestion and opinion by example analysis, in order to provide some ideas and basis for telecom enterprise's financing decision-making.

  5. Probabilistic risk analysis for nuclear power plants

    International Nuclear Information System (INIS)

    Hauptmanns, U.

    1988-01-01

    Risk analysis is applied if the calculation of risk from observed failures is not possible, because events contributing substantially to risk are too seldom, as in the case of nuclear reactors. The process of analysis provides a number of benefits. Some of them are listed. After this by no means complete enumeration of possible benefits to be derived from a risk analysis. An outline of risk studiesd for PWR's with some comments on the models used are given. The presentation is indebted to the detailed treatment of the subject given in the PRA Procedures Guide. Thereafter some results of the German Risk Study, Phase B, which is under way are communicated. The paper concludes with some remarks on probabilistic considerations in licensing procedures. (orig./DG)

  6. Single-shell tank interim stabilization risk analysis

    International Nuclear Information System (INIS)

    Basche, A.D.

    1998-01-01

    The purpose of the Single-Shell Tank (SST) Interim Stabilization Risk Analysis is to provide a cost and schedule risk analysis of HNF-2358, Rev. 1, Single-Shell Tank Interim Stabilization Project Plan (Project Plan) (Ross et al. 1998). The analysis compares the required cost profile by fiscal year (Section 4.2) and revised schedule completion date (Section 4.5) to the Project Plan. The analysis also evaluates the executability of the Project Plan and recommends a path forward for risk mitigation

  7. Multiple Sclerosis Increases Fracture Risk: A Meta-Analysis

    Directory of Open Access Journals (Sweden)

    Guixian Dong

    2015-01-01

    Full Text Available Purpose. The association between multiple sclerosis (MS and fracture risk has been reported, but results of previous studies remain controversial and ambiguous. To assess the association between MS and fracture risk, a meta-analysis was performed. Method. Based on comprehensive searches of the PubMed, Embase, and Web of Science, we identified outcome data from all articles estimating the association between MS and fracture risk. The pooled risk ratios (RRs with 95% confidence intervals (CIs were calculated. Results. A significant association between MS and fracture risk was found. This result remained statistically significant when the adjusted RRs were combined. Subgroup analysis stratified by the site of fracture suggested significant associations between MS and tibia fracture risk, femur fracture risk, hip fracture risk, pelvis fracture risk, vertebrae fracture risk, and humerus fracture risk. In the subgroup analysis by gender, female MS patients had increased fracture risk. When stratified by history of drug use, use of antidepressants, hypnotics/anxiolytics, anticonvulsants, and glucocorticoids increased the risk of fracture risk in MS patients. Conclusions. This meta-analysis demonstrated that MS was significantly associated with fracture risk.

  8. 38 CFR 75.115 - Risk analysis.

    Science.gov (United States)

    2010-07-01

    ... 38 Pensions, Bonuses, and Veterans' Relief 2 2010-07-01 2010-07-01 false Risk analysis. 75.115 Section 75.115 Pensions, Bonuses, and Veterans' Relief DEPARTMENT OF VETERANS AFFAIRS (CONTINUED) INFORMATION SECURITY MATTERS Data Breaches § 75.115 Risk analysis. If a data breach involving sensitive personal information that is processed or...

  9. An electromagnetic method for removing the communication blackout with a space vehicle upon re-entry into the atmosphere

    Science.gov (United States)

    Cheng, Jianjun; Jin, Ke; Kou, Yong; Hu, Ruifeng; Zheng, Xiaojing

    2017-03-01

    When a hypersonic vehicle travels in the Earth and Mars atmosphere, the surface of the vehicle is surrounded by a plasma layer, which is an envelope of ionized air, created from the compression and heat of the atmosphere by the shock wave. The vehicles will lose contact with ground stations known as the reentry communication blackout. Based on the magnetohydrodynamic framework and electromagnetic wave propagation theory, an analytical model is proposed to describe the effect of the effectiveness of electromagnetic mitigation scheme on removing the reentry communication blackout. C and Global Positioning System (GPS) bands, two commonly used radio bands for communication, are taken as the cases to discuss the effectiveness of the electromagnetic field mitigation scheme. The results show that the electron density near the antenna of vehicles can be reduced by the electromagnetic field, and the required external magnetic field strength is far below the one in the magnetic window method. The directions of the external electric field and magnetic field have a significant impact on the effectiveness of the mitigation scheme. Furthermore, the effect of electron collisions on the required applied electromagnetic field is discussed, and the result indicates that electron collisions are a key factor to analyze the electromagnetic mitigation scheme. Finally, the feasible regions of the applied electromagnetic field for eliminating blackout are given. These investigations could have a significant benefit on the design and optimization of electromagnetic mitigation scheme for the blackout problem.

  10. Baseline ecological risk assessment Salmon Site, Lamar County, Mississippi

    International Nuclear Information System (INIS)

    1995-04-01

    The Salmon Site (SS), formerly the Tatum Dome Test Site, located in Mississippi was the site of two nuclear and two gas explosion tests conducted between 1964 and 1970. A consequence of these testing activities is that radionuclides were released into the salt dome, where they are presently contained. During reentry drilling and other site activities, incidental liquid and solid wastes that contained radioactivity were generated, resulting in some soil, ground water and equipment contamination. As part of the remedial investigation effort, a Baseline Ecological Risk Assessment was conducted at the SS. The purpose is to gauge ecological and other environmental impacts attributable to past activities at the former test facility. The results of this facility-specific baseline risk assessment are presented in this document

  11. Baseline ecological risk assessment Salmon Site, Lamar County, Mississippi

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-04-01

    The Salmon Site (SS), formerly the Tatum Dome Test Site, located in Mississippi was the site of two nuclear and two gas explosion tests conducted between 1964 and 1970. A consequence of these testing activities is that radionuclides were released into the salt dome, where they are presently contained. During reentry drilling and other site activities, incidental liquid and solid wastes that contained radioactivity were generated, resulting in some soil, ground water and equipment contamination. As part of the remedial investigation effort, a Baseline Ecological Risk Assessment was conducted at the SS. The purpose is to gauge ecological and other environmental impacts attributable to past activities at the former test facility. The results of this facility-specific baseline risk assessment are presented in this document.

  12. Common approach of risks analysis

    International Nuclear Information System (INIS)

    Noviello, L.; Naviglio, A.

    1996-01-01

    Although, following the resolutions of the High German Court, the protection level of the human beings is an objective which can change in time, it is obvious that it is an important point when there is a risk for the population. This is true more particularly for the industrial plants whose possible accidents could affect the population. The accidents risk analysis indicates that there is no conceptual difference between the risks of a nuclear power plant and those of the other industrial plants as chemical plants, the gas distribution system and the hydraulic dams. A legislation analysis induced by the Seveso Directive for the industrial risks give some important indications which should always be followed. This work analyses more particularly the legislative situation in different European countries and identifies some of the most important characteristics. Indeed, for most of the countries, the situation is different and it is a later difficulties source for nuclear power plants. In order to strengthen this reasoning, this paper presents some preliminary results of an analysis of a nuclear power plant following the approach of other industrial plants. In conclusion, it will be necessary to analyse again the risks assessment approach for nuclear power plants because the real protection level of human beings in a country is determined by the less regulated of the dangerous industrial plants existing at the surroundings. (O.M.)

  13. Standardised risk analysis as a communication tool

    International Nuclear Information System (INIS)

    Pluess, Ch.; Montanarini, M.; Bernauer, M.

    1998-01-01

    Full text of publication follows: several European countries require a risk analysis for the production, storage or transport a dangerous goods. This requirement imposes considerable administrative effort for some sectors of the industry. In order to minimize the effort of such studies, a generic risk analysis for an industrial sector proved to help. Standardised procedures can consequently be derived for efficient performance of the risk investigations. This procedure was successfully established in Switzerland for natural gas transmission lines and fossil fuel storage plants. The development process of the generic risk analysis involved an intense discussion between industry and authorities about methodology of assessment and the criteria of acceptance. This process finally led to scientific consistent modelling tools for risk analysis and to an improved communication from the industry to the authorities and the public. As a recent example, the Holland-Italy natural gas transmission pipeline is demonstrated, where this method was successfully employed. Although this pipeline traverses densely populated areas in Switzerland, using this established communication method, the risk problems could be solved without delaying the planning process. (authors)

  14. Introduction of the risk analysis

    International Nuclear Information System (INIS)

    Campon, G.; Martinez, I.

    2013-01-01

    An introduction of risks analysis was given in the exposition which main issues were: food innocuousness, world, regional and national food context,change of paradigms, health definition, risk, codex, standardization, food chain role, trade agreement, codex alimentarius, food transmission diseases cost impact

  15. Anatomical and spiral wave reentry in a simplified model for atrial electrophysiology.

    Science.gov (United States)

    Richter, Yvonne; Lind, Pedro G; Seemann, Gunnar; Maass, Philipp

    2017-04-21

    For modeling the propagation of action potentials in the human atria, various models have been developed in the past, which take into account in detail the influence of the numerous ionic currents flowing through the cell membrane. Aiming at a simplified description, the Bueno-Orovio-Cherry-Fenton (BOCF) model for electric wave propagation in the ventricle has been adapted recently to atrial physiology. Here, we study this adapted BOCF (aBOCF) model with respect to its capability to accurately generate spatio-temporal excitation patterns found in anatomical and spiral wave reentry. To this end, we compare results of the aBOCF model with the more detailed one proposed by Courtemanche, Ramirez and Nattel (CRN model). We find that characteristic features of the reentrant excitation patterns seen in the CRN model are well captured by the aBOCF model. This opens the possibility to study origins of atrial fibrillation based on a simplified but still reliable description. Copyright © 2017 Elsevier Ltd. All rights reserved.

  16. Risk Analysis Group annual progress report 1984

    International Nuclear Information System (INIS)

    1985-06-01

    The activities of the Risk Analysis Group at Risoe during 1984 are presented. These include descriptions in some detail of work on general development topics and risk analysis performed as contractor. (author)

  17. Electrophysiological markers predicting impeding AV-block during ablation of atrioventricular nodal reentry tachycardia.

    Science.gov (United States)

    Fragakis, Nikolaos; Krexi, Lydia; Kyriakou, Panagiota; Sotiriadou, Melani; Lazaridis, Charalambos; Karamanolis, Athanasios; Dalampyras, Panagiotis; Tsakiroglou, Stelios; Skeberis, Vassilios; Tsalikakis, Dimitrios; Vassilikos, Vassilios

    2018-01-01

    Radiofrequency (RF) ablation of the slow pathway (SP) in atrioventricular nodal reentry tachycardia (AVNRT) is occasionally complicated with atrioventricular block (AVB) often predicted by junctional beats (JB) with loss of ventriculo-atrial (VA) conduction. We analyzed retrospectively 153 patients undergoing ablation of SP for typical AVNRT. Patients were divided into two age groups: 127 ≤ 70 years and 26 > 70 years. We analyzed the interval between the atrial electrogram in the His-bundle position and the distal ablation catheter [A(H)-A(RFd)] and between the distal ablation catheter and the proximal coronary sinus catheter [A(RFd)-A(CS)] before RF applications with and without JB. We evaluated if these intervals can be used as predictors of JB incidence and also of JB with loss of VA conduction. We also assessed if age influences the risk of loss of VA conduction. The A(H)-A(RFd) and A(RFd)-A(CS) intervals were significantly shorter in RF applications causing JB than those without JB (33 ± 11 ms vs 39 ± 9 ms, P JB with VA block than those with VA conduction (29 ± 11 ms vs 35 ± 11 ms, P  70 years had shorter intervals (36 ± 11 ms vs 29 ± 8 ms, P  =  0.012, 17 ± 8 ms vs 13 ± 7 ms, P  =  0.027, respectively), while VA block was more common in this age group. The A(H)-A(RFd) and A(RFd)-A(CS) intervals can be used as markers for predicting JB occurrence as well as impending AVB. JB with loss of VA conduction occur more often in older patients possibly due to a higher position of SP. © 2017 Wiley Periodicals, Inc.

  18. Study of the Use of a Terminal Controller Technique for Reentry Guidance of a Capsule-Type Vehicle

    Science.gov (United States)

    Foudriat, Edwin C.

    1961-01-01

    A study has been made of the use o f a terminal controller technique i n the guidance of a high-drag, variable-lift reentry vehicle to a desired landing point. The technique uses linearized equations of motion attained by the perturbation of the dependent variables from those of a reference trajectory. The guidance system continuously predicts the terminal range error and uses this error to control the angle of attack of the vehicle in an on-off manner until the predicted range error is within +-O.1 degrees of the required arc or +-6.9 miles.

  19. Risk-based decision analysis for groundwater operable units

    International Nuclear Information System (INIS)

    Chiaramonte, G.R.

    1995-01-01

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

  20. How to Perform an Ethical Risk Analysis (eRA).

    Science.gov (United States)

    Hansson, Sven Ove

    2018-02-26

    Ethical analysis is often needed in the preparation of policy decisions on risk. A three-step method is proposed for performing an ethical risk analysis (eRA). In the first step, the people concerned are identified and categorized in terms of the distinct but compatible roles of being risk-exposed, a beneficiary, or a decisionmaker. In the second step, a more detailed classification of roles and role combinations is performed, and ethically problematic role combinations are identified. In the third step, further ethical deliberation takes place, with an emphasis on individual risk-benefit weighing, distributional analysis, rights analysis, and power analysis. Ethical issues pertaining to subsidiary risk roles, such as those of experts and journalists, are also treated in this phase. An eRA should supplement, not replace, a traditional risk analysis that puts emphasis on the probabilities and severities of undesirable events but does not cover ethical issues such as agency, interpersonal relationships, and justice. © 2018 Society for Risk Analysis.

  1. RISK ANALYSIS IN INFORMATION TECHNOLOGY AND COMMUNICATION OUTSOURCING

    Directory of Open Access Journals (Sweden)

    Edmir Parada Vasques Prado

    2011-12-01

    Full Text Available This research aims at evaluating the risk analysis process in Information Technology and Communication (ICT outsourcing conducted by organizations of the private sector. The research is characterized by being a descriptive, quantitative and transversal type study, which was used the survey method. Data were collected through questionnaire, the sample is not random and we used a convenience sampling process. The research made contributions to understanding the risk analysis process in ICT services outsourcing, and identified statistically significant relationships between risk analysis, organization's size and its industry, and between risk analysis and diversity of outsourced services

  2. A complex dissected chronic occlusion: targeted balloon dilatation of false lumen to access true lumen, combined localized subintimal tracking and reentry, parallel wire, contralateral injection and a useful antegrade lumen re-entry technique

    Directory of Open Access Journals (Sweden)

    James W. Tam

    2012-02-01

    Full Text Available Chronic total occlusion (CTO angioplasty is one of the most challenging procedures remaining for the interventional operator. Recanalizing CTOs can improve exercise capacity, symptoms, left ventricular function and possibly reduce mortality. Multiple strategies such as escalating wire, parallel wire, seesaw, contralateral injection, subintimal tracking and re-entry (STAR, retrograde wire techniques (controlled antegrade retrograde subintimal tracking, CART, reverse CART, confluent balloon, rendezvous in coronary, and other techniques have all been described. Selection of the most appropriate approach is based on assessment of vessel course, length of occluded segment, presence of bridging collaterals, presence of bifurcating side branches at the occlusion site, and other variables. Today, with significant operator expertise and the use of available techniques, the literature reports a 50-95% success rate for recanalizing CTOs.

  3. Risk-benefit analysis and public policy: a bibliography

    Energy Technology Data Exchange (ETDEWEB)

    Clark, E.M.; Van Horn, A.J.

    1976-11-01

    Risk-benefit analysis has been implicitly practiced whenever decision-makers are confronted with decisions involving risks to life, health, or to the environment. Various methodologies have been developed to evaluate relevant criteria and to aid in assessing the impacts of alternative projects. Among these have been cost-benefit analysis, which has been widely used for project evaluation. However, in many cases it has been difficult to assign dollar costs to those criteria involving risks and benefits which are not now assigned explicit monetary values in our economic system. Hence, risk-benefit analysis has evolved to become more than merely an extension of cost-benefit analysis, and many methods have been applied to examine the trade-offs between risks and benefits. In addition, new scientific and statistical techniques have been developed for assessing current and future risks. The 950 references included in this bibliography are meant to suggest the breadth of those methodologies which have been applied to decisions involving risk.

  4. Risk-benefit analysis and public policy: a bibliography

    International Nuclear Information System (INIS)

    Clark, E.M.; Van Horn, A.J.

    1976-11-01

    Risk-benefit analysis has been implicitly practiced whenever decision-makers are confronted with decisions involving risks to life, health, or to the environment. Various methodologies have been developed to evaluate relevant criteria and to aid in assessing the impacts of alternative projects. Among these have been cost-benefit analysis, which has been widely used for project evaluation. However, in many cases it has been difficult to assign dollar costs to those criteria involving risks and benefits which are not now assigned explicit monetary values in our economic system. Hence, risk-benefit analysis has evolved to become more than merely an extension of cost-benefit analysis, and many methods have been applied to examine the trade-offs between risks and benefits. In addition, new scientific and statistical techniques have been developed for assessing current and future risks. The 950 references included in this bibliography are meant to suggest the breadth of those methodologies which have been applied to decisions involving risk

  5. Methods for Risk Analysis

    International Nuclear Information System (INIS)

    Alverbro, Karin

    2010-01-01

    Many decision-making situations today affect humans and the environment. In practice, many such decisions are made without an overall view and prioritise one or other of the two areas. Now and then these two areas of regulation come into conflict, e.g. the best alternative as regards environmental considerations is not always the best from a human safety perspective and vice versa. This report was prepared within a major project with the aim of developing a framework in which both the environmental aspects and the human safety aspects are integrated, and decisions can be made taking both fields into consideration. The safety risks have to be analysed in order to be successfully avoided and one way of doing this is to use different kinds of risk analysis methods. There is an abundance of existing methods to choose from and new methods are constantly being developed. This report describes some of the risk analysis methods currently available for analysing safety and examines the relationships between them. The focus here is mainly on human safety aspects

  6. Flood Risk Assessment Based On Security Deficit Analysis

    Science.gov (United States)

    Beck, J.; Metzger, R.; Hingray, B.; Musy, A.

    Risk is a human perception: a given risk may be considered as acceptable or unac- ceptable depending on the group that has to face that risk. Flood risk analysis of- ten estimates economic losses from damages, but neglects the question of accept- able/unacceptable risk. With input from land use managers, politicians and other stakeholders, risk assessment based on security deficit analysis determines objects with unacceptable risk and their degree of security deficit. Such a risk assessment methodology, initially developed by the Swiss federal authorities, is illustrated by its application on a reach of the Alzette River (Luxembourg) in the framework of the IRMA-SPONGE FRHYMAP project. Flood risk assessment always involves a flood hazard analysis, an exposed object vulnerability analysis, and an analysis combing the results of these two previous analyses. The flood hazard analysis was done with the quasi-2D hydraulic model FldPln to produce flood intensity maps. Flood intensity was determined by the water height and velocity. Object data for the vulnerability analysis, provided by the Luxembourg government, were classified according to their potential damage. Potential damage is expressed in terms of direct, human life and secondary losses. A thematic map was produced to show the object classification. Protection goals were then attributed to the object classes. Protection goals are assigned in terms of an acceptable flood intensity for a certain flood frequency. This is where input from land use managers and politicians comes into play. The perception of risk in the re- gion or country influences the protection goal assignment. Protection goals as used in Switzerland were used in this project. Thematic maps showing the protection goals of each object in the case study area for a given flood frequency were produced. Com- parison between an object's protection goal and the intensity of the flood that touched the object determine the acceptability of the risk and the

  7. Analysis and management of risks experienced in tunnel construction

    Directory of Open Access Journals (Sweden)

    Cagatay Pamukcu

    2015-12-01

    Full Text Available In this study, first of all, the definitions of "risk", "risk analysis", "risk assessment" and "risk management" were made to avoid any confusions about these terms and significance of risk analysis and management in engineering projects was emphasized. Then, both qualitative and quantitative risk analysis techniques were mentioned and within the scope of the study, Event Tree Analysis method was selected in order to analyze the risks regarding TBM (Tunnel Boring Machine operations in tunnel construction. After all hazards that would be encountered during tunnel construction by TBM method had been investigated, those hazards were undergoing a Preliminary Hazard Analysis to sort out and prioritize the risks with high scores. When the risk scores were taken into consideration, it was seen that the hazards with high risk scores could be classified into 4 groups which are excavation + support induced accidents, accidents stemming from geologic conditions, auxiliary works, and project contract. According to these four classified groups of initiating events, Event Tree Analysis was conducted by taking into care 4 countermeasures apart from each other. Finally, the quantitative and qualitative consequences of Event Tree Analyses, which were undertaken for all initiating events, were investigated and interpreted together by making comparisons and referring to previous studies.

  8. 49 CFR 260.17 - Credit risk premium analysis.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false Credit risk premium analysis. 260.17 Section 260... Financial Assistance § 260.17 Credit risk premium analysis. (a) When Federal appropriations are not available to cover the total subsidy cost, the Administrator will determine the Credit Risk Premium...

  9. Computational Aspects of Dam Risk Analysis: Findings and Challenges

    Directory of Open Access Journals (Sweden)

    Ignacio Escuder-Bueno

    2016-09-01

    Full Text Available In recent years, risk analysis techniques have proved to be a useful tool to inform dam safety management. This paper summarizes the outcomes of three themes related to dam risk analysis discussed in the Benchmark Workshops organized by the International Commission on Large Dams Technical Committee on “Computational Aspects of Analysis and Design of Dams.” In the 2011 Benchmark Workshop, estimation of the probability of failure of a gravity dam for the sliding failure mode was discussed. Next, in 2013, the discussion focused on the computational challenges of the estimation of consequences in dam risk analysis. Finally, in 2015, the probability of sliding and overtopping in an embankment was analyzed. These Benchmark Workshops have allowed a complete review of numerical aspects for dam risk analysis, showing that risk analysis methods are a very useful tool to analyze the risk of dam systems, including downstream consequence assessments and the uncertainty of structural models.

  10. Integrating Household Risk Mitigation Behavior in Flood Risk Analysis: An Agent-Based Model Approach.

    Science.gov (United States)

    Haer, Toon; Botzen, W J Wouter; de Moel, Hans; Aerts, Jeroen C J H

    2017-10-01

    Recent studies showed that climate change and socioeconomic trends are expected to increase flood risks in many regions. However, in these studies, human behavior is commonly assumed to be constant, which neglects interaction and feedback loops between human and environmental systems. This neglect of human adaptation leads to a misrepresentation of flood risk. This article presents an agent-based model that incorporates human decision making in flood risk analysis. In particular, household investments in loss-reducing measures are examined under three economic decision models: (1) expected utility theory, which is the traditional economic model of rational agents; (2) prospect theory, which takes account of bounded rationality; and (3) a prospect theory model, which accounts for changing risk perceptions and social interactions through a process of Bayesian updating. We show that neglecting human behavior in flood risk assessment studies can result in a considerable misestimation of future flood risk, which is in our case study an overestimation of a factor two. Furthermore, we show how behavior models can support flood risk analysis under different behavioral assumptions, illustrating the need to include the dynamic adaptive human behavior of, for instance, households, insurers, and governments. The method presented here provides a solid basis for exploring human behavior and the resulting flood risk with respect to low-probability/high-impact risks. © 2016 The Authors Risk Analysis published by Wiley Periodicals, Inc. on behalf of Society for Risk Analysis.

  11. Effects of Reentry Plasma Sheath on Mutual-Coupling Property of Array Antenna

    Directory of Open Access Journals (Sweden)

    B. W. Bai

    2015-01-01

    Full Text Available A plasma sheath enveloping a reentry vehicle would cause the failure of on-board antennas, which is an important effect that contributes to the “blackout” problem. The method of replacing the on-board single antenna with the array antennas and using beamforming technology has been proposed to mitigate “blackout” problem by many other researchers. Because the plasma sheath is a reflective medium, plasma will alter the mutual coupling between array elements and degrade the beamforming performance of array antenna. In this paper, the effects of the plasma sheath on the mutual coupling properties between adjacent array elements are studied utilizing the algorithm of finite integration technique. Results show that mutual coupling coefficients of array elements are deteriorating more seriously with the decrease of collision frequency. Moreover, when electron density and collision frequency are both large, plasma sheath improves the mutual coupling property of array elements; this conclusion suggests that replacing the on-board single antenna with the array antennas and using beamforming technology can be adopted to mitigate the blackout problem in this condition.

  12. Putting problem formulation at the forefront of GMO risk analysis.

    Science.gov (United States)

    Tepfer, Mark; Racovita, Monica; Craig, Wendy

    2013-01-01

    When applying risk assessment and the broader process of risk analysis to decisions regarding the dissemination of genetically modified organisms (GMOs), the process has a tendency to become remarkably complex. Further, as greater numbers of countries consider authorising the large-scale dissemination of GMOs, and as GMOs with more complex traits reach late stages of development, there has been increasing concern about the burden posed by the complexity of risk analysis. We present here an improved approach for GMO risk analysis that gives a central role to problem formulation. Further, the risk analysis strategy has been clarified and simplified in order to make rigorously scientific risk assessment and risk analysis more broadly accessible to diverse stakeholder groups.

  13. Streamlining project delivery through risk analysis.

    Science.gov (United States)

    2015-08-01

    Project delivery is a significant area of concern and is subject to several risks throughout Plan Development : Process (PDP). These risks are attributed to major areas of project development, such as environmental : analysis, right-of-way (ROW) acqu...

  14. Reliability and risk analysis methods research plan

    International Nuclear Information System (INIS)

    1984-10-01

    This document presents a plan for reliability and risk analysis methods research to be performed mainly by the Reactor Risk Branch (RRB), Division of Risk Analysis and Operations (DRAO), Office of Nuclear Regulatory Research. It includes those activities of other DRAO branches which are very closely related to those of the RRB. Related or interfacing programs of other divisions, offices and organizations are merely indicated. The primary use of this document is envisioned as an NRC working document, covering about a 3-year period, to foster better coordination in reliability and risk analysis methods development between the offices of Nuclear Regulatory Research and Nuclear Reactor Regulation. It will also serve as an information source for contractors and others to more clearly understand the objectives, needs, programmatic activities and interfaces together with the overall logical structure of the program

  15. Multi-hazard risk analysis for management strategies

    Science.gov (United States)

    Kappes, M.; Keiler, M.; Bell, R.; Glade, T.

    2009-04-01

    Risk management is very often operating in a reactive way, responding to an event, instead of proactive starting with risk analysis and building up the whole process of risk evaluation, prevention, event management and regeneration. Since damage and losses from natural hazards raise continuously more and more studies, concepts (e.g. Switzerland or South Tyrol-Bolozano) and software packages (e.g. ARMAGEDOM, HAZUS or RiskScape) are developed to guide, standardize and facilitate the risk analysis. But these approaches focus on different aspects and are mostly closely adapted to the situation (legislation, organization of the administration, specific processes etc.) of the specific country or region. We propose in this study the development of a flexible methodology for multi-hazard risk analysis, identifying the stakeholders and their needs, processes and their characteristics, modeling approaches as well as incoherencies occurring by combining all these different aspects. Based on this concept a flexible software package will be established consisting of ArcGIS as central base and being complemented by various modules for hazard modeling, vulnerability assessment and risk calculation. Not all modules will be developed newly but taken from the current state-of-the-art and connected or integrated into ArcGIS. For this purpose two study sites, Valtellina in Italy and Bacelonnette in France, were chosen and the hazards types debris flows, rockfalls, landslides, avalanches and floods are planned to be included in the tool for a regional multi-hazard risk analysis. Since the central idea of this tool is its flexibility this will only be a first step, in the future further processes and scales can be included and the instrument thus adapted to any study site.

  16. Environmental risk analysis of hazardous material rail transportation

    Energy Technology Data Exchange (ETDEWEB)

    Saat, Mohd Rapik, E-mail: mohdsaat@illinois.edu [Department of Civil and Environmental Engineering, University of Illinois at Urbana-Champaign, 1243 Newmark Civil Engineering Laboratory, 205 North Mathews Avenue, Urbana, IL 61801 (United States); Werth, Charles J.; Schaeffer, David [Department of Civil and Environmental Engineering, University of Illinois at Urbana-Champaign, 1243 Newmark Civil Engineering Laboratory, 205 North Mathews Avenue, Urbana, IL 61801 (United States); Yoon, Hongkyu [Sandia National Laboratories, Albuquerque, NM 87123 (United States); Barkan, Christopher P.L. [Department of Civil and Environmental Engineering, University of Illinois at Urbana-Champaign, 1243 Newmark Civil Engineering Laboratory, 205 North Mathews Avenue, Urbana, IL 61801 (United States)

    2014-01-15

    Highlights: • Comprehensive, nationwide risk assessment of hazardous material rail transportation. • Application of a novel environmental (i.e. soil and groundwater) consequence model. • Cleanup cost and total shipment distance are the most significant risk factors. • Annual risk varies from $20,000 to $560,000 for different products. • Provides information on the risk cost associated with specific product shipments. -- Abstract: An important aspect of railroad environmental risk management involves tank car transportation of hazardous materials. This paper describes a quantitative, environmental risk analysis of rail transportation of a group of light, non-aqueous-phase liquid (LNAPL) chemicals commonly transported by rail in North America. The Hazardous Materials Transportation Environmental Consequence Model (HMTECM) was used in conjunction with a geographic information system (GIS) analysis of environmental characteristics to develop probabilistic estimates of exposure to different spill scenarios along the North American rail network. The risk analysis incorporated the estimated clean-up cost developed using the HMTECM, route-specific probability distributions of soil type and depth to groundwater, annual traffic volume, railcar accident rate, and tank car safety features, to estimate the nationwide annual risk of transporting each product. The annual risk per car-mile (car-km) and per ton-mile (ton-km) was also calculated to enable comparison between chemicals and to provide information on the risk cost associated with shipments of these products. The analysis and the methodology provide a quantitative approach that will enable more effective management of the environmental risk of transporting hazardous materials.

  17. Environmental risk analysis of hazardous material rail transportation

    International Nuclear Information System (INIS)

    Saat, Mohd Rapik; Werth, Charles J.; Schaeffer, David; Yoon, Hongkyu; Barkan, Christopher P.L.

    2014-01-01

    Highlights: • Comprehensive, nationwide risk assessment of hazardous material rail transportation. • Application of a novel environmental (i.e. soil and groundwater) consequence model. • Cleanup cost and total shipment distance are the most significant risk factors. • Annual risk varies from $20,000 to $560,000 for different products. • Provides information on the risk cost associated with specific product shipments. -- Abstract: An important aspect of railroad environmental risk management involves tank car transportation of hazardous materials. This paper describes a quantitative, environmental risk analysis of rail transportation of a group of light, non-aqueous-phase liquid (LNAPL) chemicals commonly transported by rail in North America. The Hazardous Materials Transportation Environmental Consequence Model (HMTECM) was used in conjunction with a geographic information system (GIS) analysis of environmental characteristics to develop probabilistic estimates of exposure to different spill scenarios along the North American rail network. The risk analysis incorporated the estimated clean-up cost developed using the HMTECM, route-specific probability distributions of soil type and depth to groundwater, annual traffic volume, railcar accident rate, and tank car safety features, to estimate the nationwide annual risk of transporting each product. The annual risk per car-mile (car-km) and per ton-mile (ton-km) was also calculated to enable comparison between chemicals and to provide information on the risk cost associated with shipments of these products. The analysis and the methodology provide a quantitative approach that will enable more effective management of the environmental risk of transporting hazardous materials

  18. RISK ANALYSIS APPLIED IN OIL EXPLORATION AND PRODUCTION

    African Journals Online (AJOL)

    ES Obe

    aDepartment of Civil Engineering, University of Nigeria, Nsukka, Enugu State, Nigeria. ... The analysis in this work is ... risk analysis, oil field, risk management, projects, investment opportunity. 1. .... own merit but since the company has limited.

  19. Risks of nuclear waste disposal in space. III - Long-term orbital evolution of small particle distribution

    Science.gov (United States)

    Friedlander, A. L.; Wells, W. C.

    1980-01-01

    A study of long term risks is presented that treats an additional pathway that could result in earth reentry, namely, small radioactive particles released in solar orbit due to payload fragmentation by accidental explosion or meteoroid impact. A characterization of such an event and of the initial mass size distribution of particles is given for two extremes of waste form strength. Attention is given to numerical results showing the mass-time distribution of material and the fraction of initial mass intercepted by earth. It is concluded that it appears that program planners need not be to concerned about the risks of this particular failure mechanism and return pathway.

  20. Cyber Risk Management for Critical Infrastructure: A Risk Analysis Model and Three Case Studies.

    Science.gov (United States)

    Paté-Cornell, M-Elisabeth; Kuypers, Marshall; Smith, Matthew; Keller, Philip

    2018-02-01

    Managing cyber security in an organization involves allocating the protection budget across a spectrum of possible options. This requires assessing the benefits and the costs of these options. The risk analyses presented here are statistical when relevant data are available, and system-based for high-consequence events that have not happened yet. This article presents, first, a general probabilistic risk analysis framework for cyber security in an organization to be specified. It then describes three examples of forward-looking analyses motivated by recent cyber attacks. The first one is the statistical analysis of an actual database, extended at the upper end of the loss distribution by a Bayesian analysis of possible, high-consequence attack scenarios that may happen in the future. The second is a systems analysis of cyber risks for a smart, connected electric grid, showing that there is an optimal level of connectivity. The third is an analysis of sequential decisions to upgrade the software of an existing cyber security system or to adopt a new one to stay ahead of adversaries trying to find their way in. The results are distributions of losses to cyber attacks, with and without some considered countermeasures in support of risk management decisions based both on past data and anticipated incidents. © 2017 Society for Risk Analysis.

  1. E2F-dependent induction of p14ARF during cell cycle re-entry in human T cells

    DEFF Research Database (Denmark)

    del Arroyo, Ana Gutierrez; El Messaoudi, Selma; Clark, Paula A

    2007-01-01

    The ARF protein, encoded by alternate exon usage within the CDKN2A locus, provides a link between the retinoblastoma (pRb) and p53 tumor suppressor pathways. Agents that disable pRb or otherwise impinge on the E2F family of transcription factors induce expression of ARF, resulting in stabilization...... of p53 and activation of p53-regulated genes. However, in some cell types ARF is not induced upon cell cycle re-entry, as expected of a conventional E2F target gene, leading to the suggestion that the ARF promoter only responds to supra-physiological or aberrant levels of E2F. These properties have...

  2. Urban flooding and health risk analysis by use of quantitative microbial risk assessment

    DEFF Research Database (Denmark)

    Andersen, Signe Tanja

    D thesis is to identify the limitations and possibilities for optimising microbial risk assessments of urban flooding through more evidence-based solutions, including quantitative microbial data and hydrodynamic water quality models. The focus falls especially on the problem of data needs and the causes......, but also when wading through a flooded area. The results in this thesis have brought microbial risk assessments one step closer to more uniform and repeatable risk analysis by using actual and relevant measured data and hydrodynamic water quality models to estimate the risk from flooding caused...... are expected to increase in the future. To ensure public health during extreme rainfall, solutions are needed, but limited knowledge on microbial water quality, and related health risks, makes it difficult to implement microbial risk analysis as a part of the basis for decision making. The main aim of this Ph...

  3. Probabilistic risk analysis in chemical engineering

    International Nuclear Information System (INIS)

    Schmalz, F.

    1991-01-01

    In risk analysis in the chemical industry, recognising potential risks is considered more important than assessing their quantitative extent. Even in assessing risks, emphasis is not on the probability involved but on the possible extent. Qualitative assessment has proved valuable here. Probabilistic methods are used in individual cases where the wide implications make it essential to be able to assess the reliability of safety precautions. In this case, assessment therefore centres on the reliability of technical systems and not on the extent of a chemical risk. 7 figs

  4. Method for environmental risk analysis (MIRA) revision 2007

    International Nuclear Information System (INIS)

    2007-04-01

    OLF's instruction manual for carrying out environmental risk analyses provides a united approach and a common framework for environmental risk assessments. This is based on the best information available. The manual implies standardizations of a series of parameters, input data and partial analyses that are included in the environmental risk analysis. Environmental risk analyses carried out according to the MIRA method will thus be comparable between fields and between companies. In this revision an update of the text in accordance with today's practice for environmental risk analyses and prevailing regulations is emphasized. Moreover, method adjustments for especially protected beach habitats have been introduced, as well as a general method for estimating environmental risk concerning fish. Emphasis has also been put on improving environmental risk analysis' possibilities to contribute to a better management of environmental risk in the companies (ml)

  5. Evaluating the risks of clinical research: direct comparative analysis.

    Science.gov (United States)

    Rid, Annette; Abdoler, Emily; Roberson-Nay, Roxann; Pine, Daniel S; Wendler, David

    2014-09-01

    Many guidelines and regulations allow children and adolescents to be enrolled in research without the prospect of clinical benefit when it poses minimal risk. However, few systematic methods exist to determine when research risks are minimal. This situation has led to significant variation in minimal risk judgments, raising concern that some children are not being adequately protected. To address this concern, we describe a new method for implementing the widely endorsed "risks of daily life" standard for minimal risk. This standard defines research risks as minimal when they do not exceed the risks posed by daily life activities or routine examinations. This study employed a conceptual and normative analysis, and use of an illustrative example. Different risks are composed of the same basic elements: Type, likelihood, and magnitude of harm. Hence, one can compare the risks of research and the risks of daily life by comparing the respective basic elements with each other. We use this insight to develop a systematic method, direct comparative analysis, for implementing the "risks of daily life" standard for minimal risk. The method offers a way of evaluating research procedures that pose the same types of risk as daily life activities, such as the risk of experiencing anxiety, stress, or other psychological harm. We thus illustrate how direct comparative analysis can be applied in practice by using it to evaluate whether the anxiety induced by a respiratory CO2 challenge poses minimal or greater than minimal risks in children and adolescents. Direct comparative analysis is a systematic method for applying the "risks of daily life" standard for minimal risk to research procedures that pose the same types of risk as daily life activities. It thereby offers a method to protect children and adolescents in research, while ensuring that important studies are not blocked because of unwarranted concerns about research risks.

  6. From the ideal to the real world: a phenomenological inquiry into student sojourners' reentry adaptation.

    Science.gov (United States)

    Hsiao, Feilin

    2011-01-01

    This phenomenological study examines the thematic structure of reentry transition for international music therapy graduates who have returned home after studying in the United States. Emphasis is placed upon career development. Standardized open-ended interviews were used to obtain rich and in-depth descriptions of the participants' experiences. Ten music therapists from six countries participated in the study. The themes that emerged from the data include moving from the ideal to the real world, shifting from the role of student to professional, confronting reality and working through challenges, and achieving personal growth and self-transformation. The dynamics of cross-cultural comparison, confronting the home culture, and redefining music therapy and professional identities within the local cultural context are illustrated via quotations from the participants. Implications and recommendations for music therapy education and career preparation for international graduates are discussed.

  7. Risk Analysis for Unintentional Slide Deployment During Airline Operations.

    Science.gov (United States)

    Ayra, Eduardo S; Insua, David Ríos; Castellanos, María Eugenia; Larbi, Lydia

    2015-09-01

    We present a risk analysis undertaken to mitigate problems in relation to the unintended deployment of slides under normal operations within a commercial airline. This type of incident entails relevant costs for the airline industry. After assessing the likelihood and severity of its consequences, we conclude that such risks need to be managed. We then evaluate the effectiveness of various countermeasures, describing and justifying the chosen ones. We also discuss several issues faced when implementing and communicating the proposed measures, thus fully illustrating the risk analysis process. © 2015 Society for Risk Analysis.

  8. Mare Risk Analysis monitor

    International Nuclear Information System (INIS)

    Fuente Prieto, I.; Alonso, P.; Carretero Fernandino, J. A.

    2000-01-01

    The Nuclear Safety Council's requirement that Spanish power plants comply with the requirements of the Maintenance Rule associated with plant risk assessment during power operation, arising from the partial unavailability of systems due to the maintenance activities, has led to need for additional tools to facilitate compliance with said requirements. While the impact on risk produced by individual equipment unavailabilities can easily be evaluated, either qualitatively or quantitatively, the process becomes more complicated when un programmed unavailabilities simultaneously occur in various systems, making it necessary to evaluate their functional impact. It is especially complex in the case of support systems that can affect the functionality of multiple systems. In view of the above, a computer application has been developed that is capable of providing the operator with quick answers based on the specific plant model in order to allow fast risk assessment using the information compiled as part of the Probabilistic Safety Analysis. The paper describes the most important characteristics of this application and the basic design requirements of the MARE Risk Monitor. (Author)

  9. Bayesian-network-based safety risk analysis in construction projects

    International Nuclear Information System (INIS)

    Zhang, Limao; Wu, Xianguo; Skibniewski, Miroslaw J.; Zhong, Jingbing; Lu, Yujie

    2014-01-01

    This paper presents a systemic decision support approach for safety risk analysis under uncertainty in tunnel construction. Fuzzy Bayesian Networks (FBN) is used to investigate causal relationships between tunnel-induced damage and its influential variables based upon the risk/hazard mechanism analysis. Aiming to overcome limitations on the current probability estimation, an expert confidence indicator is proposed to ensure the reliability of the surveyed data for fuzzy probability assessment of basic risk factors. A detailed fuzzy-based inference procedure is developed, which has a capacity of implementing deductive reasoning, sensitivity analysis and abductive reasoning. The “3σ criterion” is adopted to calculate the characteristic values of a triangular fuzzy number in the probability fuzzification process, and the α-weighted valuation method is adopted for defuzzification. The construction safety analysis progress is extended to the entire life cycle of risk-prone events, including the pre-accident, during-construction continuous and post-accident control. A typical hazard concerning the tunnel leakage in the construction of Wuhan Yangtze Metro Tunnel in China is presented as a case study, in order to verify the applicability of the proposed approach. The results demonstrate the feasibility of the proposed approach and its application potential. A comparison of advantages and disadvantages between FBN and fuzzy fault tree analysis (FFTA) as risk analysis tools is also conducted. The proposed approach can be used to provide guidelines for safety analysis and management in construction projects, and thus increase the likelihood of a successful project in a complex environment. - Highlights: • A systemic Bayesian network based approach for safety risk analysis is developed. • An expert confidence indicator for probability fuzzification is proposed. • Safety risk analysis progress is extended to entire life cycle of risk-prone events. • A typical

  10. On the validation of risk analysis-A commentary

    International Nuclear Information System (INIS)

    Rosqvist, Tony

    2010-01-01

    Aven and Heide (2009) [1] provided interesting views on the reliability and validation of risk analysis. The four validation criteria presented are contrasted with modelling features related to the relative frequency-based and Bayesian approaches to risk analysis. In this commentary I would like to bring forth some issues on validation that partly confirm and partly suggest changes in the interpretation of the introduced validation criteria-especially, in the context of low probability-high consequence systems. The mental model of an expert in assessing probabilities is argued to be a key notion in understanding the validation of a risk analysis.

  11. Quantitative risk assessment using the capacity-demand analysis

    International Nuclear Information System (INIS)

    Morgenroth, M.; Donnelly, C.R.; Westermann, G.D.; Huang, J.H.S.; Lam, T.M.

    1999-01-01

    The hydroelectric industry's recognition of the importance of avoiding unexpected failure, or forced outages, led to the development of probabilistic, or risk-based, methods in order to attempt to quantify exposures. Traditionally, such analysis has been carried out by qualitative assessments, relying on experience and sound engineering judgment to determine the optimum time to maintain, repair or replace a part or system. Depending on the nature of the problem, however, and the level of experience of those included in the decision making process, it is difficult to find a balance between acting proactively and accepting some amount of risk. The development of a practical means for establishing the probability of failure of any part or system, based on the determination of the statistical distribution of engineering properties such as acting stresses, is discussed. The capacity-demand analysis methodology, coupled with probablistic, risk-based analysis, permits all the factors associated with a decision to rehabilitate or replace a part, including the risks associated with the timing of the decision, to be assessed in a transparent and defendable manner. The methodology does not eliminate judgment altogether, but does move it from the level of estimating the risk of failure to the lower level of estimating variability in material properties, uncertainty in loading, and the uncertainties inherent in any engineering analysis. The method was successfully used in 1998 to carry out a comprehensive, economic risk analysis for the entire water conveyance system of a 90 year old hydropower station. The analysis included a number of diverse parts ranging from rock slopes and aging steel and concrete conduits, and the method allowed a rational assessment of the risks associated with reach of these varied parts to be determined, permitting the essential remedial works to be prioritized. 14 refs., 4 figs

  12. Low-cost development of the Algyoefield in Hungary by means of horizontal re-entry boreholes; Die kostenguenstige Entwicklung des Algyoe-West-Feldes in Ungarn durch horizontale Re-Entry-Bohrungen

    Energy Technology Data Exchange (ETDEWEB)

    Kinzel, H. [Weatherford Oil Tool GmbH, Langenhagen (Germany); Osz, A. [Magyar Olaj (MOL), Budapest (Hungary); Kerk, T. [Becfield Drilling Services, Edemissen-Berkhoepen (Germany)

    1998-12-31

    Planning and implementation of a typical re-entry borehole in southern Hungary are described. The cost is about half that of a new borehole, and the available infrastructure can be used. The production index of a typical Algyoehorizontal borehole is higher by a factor of 12 than for a vertical borehole in the same field. (orig.) [Deutsch] Anhand einer Beispielbohrung (Algyoe488) wird die Planung und Durchfuehrung einer typischen Re-Entry Bohrung in Suedungarn beschrieben. Durch die weitgehende Verwendung von standardisierten Komponenten und Verfahren sowie durch die enge Zusammenarbeit zweier deutscher Service Unternehmen mit dem Auftraggeber wurde bei insgesamt 35 Horizontalbohrungen in Ungarn der Effekt der Lernkurve zur optimierten Erstellung der Bohrung und damit zur Kostensenkung effektiv eingesetzt. Die so aufgearbeiteten Bohrungen werden im Vergleich zu einer neuen Bohrung fuer etwa die Haelfte der Kosten erstellt. Die vorhandene Infrastruktur des Feldes kann weiter verwendet werden. Der Produktionsindex einer typischen AlgyoeHorizontalbohrung liegt um den Faktor 12 hoeher als eine Vertikalbohrung im gleichen Feld. (orig.)

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

    International Nuclear Information System (INIS)

    Luo, Pengcheng; Hu, Yang

    2013-01-01

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

  14. Instability risk analysis and risk assessment system establishment of underground storage caverns in bedded salt rock

    Science.gov (United States)

    Jing, Wenjun; Zhao, Yan

    2018-02-01

    Stability is an important part of geotechnical engineering research. The operating experiences of underground storage caverns in salt rock all around the world show that the stability of the caverns is the key problem of safe operation. Currently, the combination of theoretical analysis and numerical simulation are the mainly adopts method of reserve stability analysis. This paper introduces the concept of risk into the stability analysis of underground geotechnical structure, and studies the instability of underground storage cavern in salt rock from the perspective of risk analysis. Firstly, the definition and classification of cavern instability risk is proposed, and the damage mechanism is analyzed from the mechanical angle. Then the main stability evaluating indicators of cavern instability risk are proposed, and an evaluation method of cavern instability risk is put forward. Finally, the established cavern instability risk assessment system is applied to the analysis and prediction of cavern instability risk after 30 years of operation in a proposed storage cavern group in the Huai’an salt mine. This research can provide a useful theoretical base for the safe operation and management of underground storage caverns in salt rock.

  15. Analysis of risk factors and risk assessment for ischemic stroke recurrence

    Directory of Open Access Journals (Sweden)

    Xiu-ying LONG

    2016-08-01

    Full Text Available Objective To screen the risk factors for recurrence of ischemic stroke and to assess the risk of recurrence. Methods Essen Stroke Risk Score (ESRS was used to evaluate the risk of recurrence in 176 patients with ischemic stroke (96 cases of first onset and 80 cases of recurrence. Univariate and multivariate stepwise Logistic regression analysis was used to screen risk factors for recurrence of ischemic stroke.  Results There were significant differences between first onset group and recurrence group on age, the proportion of > 75 years old, hypertension, diabetes, coronary heart disease, peripheral angiopathy, transient ischemic attack (TIA or ischemic stroke, drinking and ESRS score (P < 0.05, for all. First onset group included one case of ESRS 0 (1.04%, 8 cases of 1 (8.33%, 39 cases of 2 (40.63%, 44 cases of 3 (45.83%, 4 cases of 4 (4.17%. Recurrence group included 2 cases of ESRS 3 (2.50%, 20 cases of 4 (25% , 37 cases of 5 (46.25% , 18 cases of 6 (22.50% , 3 cases of 7 (3.75% . There was significant difference between 2 groups (Z = -11.376, P = 0.000. Logistic regression analysis showed ESRS > 3 score was independent risk factor for recurrence of ischemic stroke (OR = 31.324, 95%CI: 3.934-249.430; P = 0.001.  Conclusions ESRS > 3 score is the independent risk factor for recurrence of ischemic stroke. It is important to strengthen risk assessment of recurrence of ischemic stroke. To screen and control risk factors is the key to secondary prevention of ischemic stroke. DOI: 10.3969/j.issn.1672-6731.2016.07.011

  16. Risk analysis of industrial plants operation

    International Nuclear Information System (INIS)

    Hubert, Philippe

    1989-12-01

    This study examines the possibilities of systematic technology risk analysis in view of territorial management (city, urban community, region), including chronic and accidental risks. The objective was to relate this evaluation with those done for permanent water and air pollution. Risk management for pollution are done for a long time. A number of studies were done in urban communities and regions both for air and water pollution. The second objective is related to management of industrial risks: nuclear, petrochemical, transport of hazardous material, pipelines, etc. At the beginning, three possibilities of effects are taken into account: human health, economic aspect and water, and possibilities of evaluation are identified. Elements of risk identification are presented for quantification of results [fr

  17. It's Deja Vu All over Again: Using Multiple-Spell Discrete-Time Survival Analysis.

    Science.gov (United States)

    Willett, John B.; Singer, Judith D.

    1995-01-01

    The multiple-spell discrete-time survival analysis method is introduced and illustrated using longitudinal data on exit from and reentry into the teaching profession. The method is applicable to many educational problems involving the sequential occurrence of disparate events or episodes. (SLD)

  18. [Survival analysis with competing risks: estimating failure probability].

    Science.gov (United States)

    Llorca, Javier; Delgado-Rodríguez, Miguel

    2004-01-01

    To show the impact of competing risks of death on survival analysis. We provide an example of survival time without chronic rejection after heart transplantation, where death before rejection acts as a competing risk. Using a computer simulation, we compare the Kaplan-Meier estimator and the multiple decrement model. The Kaplan-Meier method overestimated the probability of rejection. Next, we illustrate the use of the multiple decrement model to analyze secondary end points (in our example: death after rejection). Finally, we discuss Kaplan-Meier assumptions and why they fail in the presence of competing risks. Survival analysis should be adjusted for competing risks of death to avoid overestimation of the risk of rejection produced with the Kaplan-Meier method.

  19. Quantitative risk analysis of a space shuttle subsystem

    International Nuclear Information System (INIS)

    Frank, M.V.

    1989-01-01

    This paper reports that in an attempt to investigate methods for risk management other than qualitative analysis techniques, NASA has funded pilot study quantitative risk analyses for space shuttle subsystems. The authors performed one such study of two shuttle subsystems with McDonnell Douglas Astronautics Company. The subsystems were the auxiliary power units (APU) on the orbiter, and the hydraulic power units on the solid rocket booster. The technology and results of the APU study are presented in this paper. Drawing from a rich in-flight database as well as from a wealth of tests and analyses, the study quantitatively assessed the risk of APU-initiated scenarios on the shuttle during all phases of a flight mission. Damage states of interest were loss of crew/vehicle, aborted mission, and launch scrub. A quantitative risk analysis approach to deciding on important items for risk management was contrasted with the current NASA failure mode and effects analysis/critical item list approach

  20. Finite-Time Reentry Attitude Control Using Time-Varying Sliding Mode and Disturbance Observer

    Directory of Open Access Journals (Sweden)

    Xuzhong Wu

    2015-01-01

    Full Text Available This paper presents the finite-time attitude control problem for reentry vehicle with redundant actuators in consideration of planet uncertainties and external disturbances. Firstly, feedback linearization technique is used to cancel the nonlinearities of equations of motion to construct a basic mode for attitude controller. Secondly, two kinds of time-varying sliding mode control methods with disturbance observer are integrated with the basic mode in order to enhance the control performance and system robustness. One method is designed based on boundary layer technique and the other is a novel second-order sliding model control method. The finite-time stability analyses of both resultant closed-loop systems are carried out. Furthermore, after attitude controller produces the torque commands, an optimization control allocation approach is introduced to allocate them into aerodynamic surface deflections and on-off reaction control system thrusts. Finally, the numerical simulation results demonstrate that both of the time-varying sliding mode control methods are robust to uncertainties and disturbances without chattering phenomenon. Moreover, the proposed second-order sliding mode control method possesses better control accuracy.

  1. U1 snRNP Alteration and Neuronal Cell Cycle Reentry in Alzheimer Disease

    Directory of Open Access Journals (Sweden)

    Bing Bai

    2018-03-01

    Full Text Available The aberrancy of U1 small nuclear ribonucleoprotein (snRNP complex and RNA splicing has been demonstrated in Alzheimer’s disease (AD. Importantly, the U1 proteopathy is AD-specific, widespread and early-occurring, thus providing a very unique clue to the AD pathogenesis. The prominent feature of U1 histopathology is its nuclear depletion and redistribution in the neuronal cytoplasm. According to the preliminary data, the initial U1 cytoplasmic distribution pattern is similar to the subcellular translocation of the spliceosome in cells undergoing mitosis. This implies that the U1 mislocalization might reflect the neuronal cell cycle-reentry (CCR which has been extensively evidenced in AD brains. The CCR phenomenon explains the major molecular and cellular events in AD brains, such as Tau and amyloid precursor protein (APP phosphorylation, and the possible neuronal death through mitotic catastrophe (MC. Furthermore, the CCR might be mechanistically linked to inflammation, a critical factor in the AD etiology according to the genetic evidence. Therefore, the discovery of U1 aberrancy might strengthen the involvement of CCR in the AD neuronal degeneration.

  2. New algorithm for risk analysis in radiotherapy

    International Nuclear Information System (INIS)

    Torres, Antonio; Montes de Oca, Joe

    2015-01-01

    Risk analyses applied to radiotherapy treatments have become an undeniable necessity, considering the dangers generated by the combination of using powerful radiation fields on patients and the occurrence of human errors and equipment failures during these treatments. The technique par excellence to execute these analyses has been the risk matrix. This paper presents the development of a new algorithm to execute the task with wide graphic and analytic potentialities, thus transforming it into a very useful option for risk monitoring and the optimization of quality assurance. The system SECURE- MR, which is the basic software of this algorithm, has been successfully used in risk analysis regarding different kinds of radiotherapies. Compared to previous methods, It offers new possibilities of analysis considering risk controlling factors as the robustness of reducers of initiators frequency and its consequences. Their analytic capacities and graphs allow novel developments to classify risk contributing factors, to represent information processes as well as accidental sequences. The paper shows the application of the proposed system to a generic process of radiotherapy treatment using a lineal accelerator. (author)

  3. Modeling issues in nuclear plant fire risk analysis

    International Nuclear Information System (INIS)

    Siu, N.

    1989-01-01

    This paper discusses various issues associated with current models for analyzing the risk due to fires in nuclear power plants. Particular emphasis is placed on the fire growth and suppression models, these being unique to the fire portion of the overall risk analysis. Potentially significant modeling improvements are identified; also discussed are a variety of modeling issues where improvements will help the credibility of the analysis, without necessarily changing the computed risk significantly. The mechanistic modeling of fire initiation is identified as a particularly promising improvement for reducing the uncertainties in the predicted risk. 17 refs., 5 figs. 2 tabs

  4. Comparative risk analysis for the Rocky Flats Plant integrated project planning

    International Nuclear Information System (INIS)

    Jones, M.E.; Shain, D.I.

    1994-01-01

    The Rocky Flats Plant is developing, with active stakeholder participation, a comprehensive planning strategy that will support transition of the Rocky Flats Plant from a nuclear weapons production facility to site cleanup and final disposition. Consideration of the interrelated nature of sitewide problems, such as material movement and disposition, facility and land use endstates, costs, relative risks to workers and the public, and waste disposition are all needed. Comparative Risk Analysis employs both incremental risk and cumulative risk evaluations to compare risks from postulated options or endstates and is an analytical tool for the Rocky Flats Plant Integrated Project Planning which can assist a decision-maker in evaluating relative risks among proposed remediation activity. However, risks from all of the remediation activities, decontamination and decommissioning activities, and normal ongoing operations are imposed upon the Rocky Flats workers, the surrounding public, and the environment. Comparative Risk Analysis will provide risk information, both human health and ecological, to aid in reducing unnecessary resource and monetary expenditures by focusing these resources on the largest risks first. Comparative Risk Analysis has been developed to aggregate various incremental risk estimates to develop a site cumulative risk estimate. The Comparative Risk Analysis methodology Group, consisting of community stakeholders, was established. Early stakeholder involvement in the risk analysis methodology development provides an opportunity for stakeholders to influence the risk information delivered to a decision-maker. This paper discusses development of the Comparative Risk Analysis methodology, stakeholder participation and lessons learned from these challenges

  5. A Second Chance to Dream: Initiating ODeL in Secondary School Re-Entry Programs for Young Adult Secondary School Dropouts the Case of Mumias District, Western Kenya

    Science.gov (United States)

    Musita, Richard; Ogange, Betty O.; Lugendo, Dorine

    2018-01-01

    The Kenyan education system has very limited re-entry options for learners who drop out before attaining secondary school certificate. It is very difficult to access training and or secure a job that requires at least secondary school education. This study examined the prospects of initiating Open and Distance e-Learning(ODeL) in re-entry…

  6. Risk analysis as a decision tool

    International Nuclear Information System (INIS)

    Yadigaroglu, G.; Chakraborty, S.

    1985-01-01

    From 1983 - 1985 a lecture series entitled ''Risk-benefit analysis'' was held at the Swiss Federal Institute of Technology (ETH), Zurich, in cooperation with the Central Department for the Safety of Nuclear Installations of the Swiss Federal Agency of Energy Economy. In that setting the value of risk-oriented evaluation models as a decision tool in safety questions was discussed on a broad basis. Experts of international reputation from the Federal Republic of Germany, France, Canada, the United States and Switzerland have contributed to report in this joint volume on the uses of such models. Following an introductory synopsis on risk analysis and risk assessment the book deals with practical examples in the fields of medicine, nuclear power, chemistry, transport and civil engineering. Particular attention is paid to the dialogue between analysts and decision makers taking into account the economic-technical aspects and social values. The recent chemical disaster in the Indian city of Bhopal again signals the necessity of such analyses. All the lectures were recorded individually. (orig./HP) [de

  7. Network theory-based analysis of risk interactions in large engineering projects

    International Nuclear Information System (INIS)

    Fang, Chao; Marle, Franck; Zio, Enrico; Bocquet, Jean-Claude

    2012-01-01

    This paper presents an approach based on network theory to deal with risk interactions in large engineering projects. Indeed, such projects are exposed to numerous and interdependent risks of various nature, which makes their management more difficult. In this paper, a topological analysis based on network theory is presented, which aims at identifying key elements in the structure of interrelated risks potentially affecting a large engineering project. This analysis serves as a powerful complement to classical project risk analysis. Its originality lies in the application of some network theory indicators to the project risk management field. The construction of the risk network requires the involvement of the project manager and other team members assigned to the risk management process. Its interpretation improves their understanding of risks and their potential interactions. The outcomes of the analysis provide a support for decision-making regarding project risk management. An example of application to a real large engineering project is presented. The conclusion is that some new insights can be found about risks, about their interactions and about the global potential behavior of the project. - Highlights: ► The method addresses the modeling of complexity in project risk analysis. ► Network theory indicators enable other risks than classical criticality analysis to be highlighted. ► This topological analysis improves project manager's understanding of risks and risk interactions. ► This helps project manager to make decisions considering the position in the risk network. ► An application to a real tramway implementation project in a city is provided.

  8. Risk analysis methodologies for the transportation of radioactive materials

    International Nuclear Information System (INIS)

    Geffen, C.A.

    1983-05-01

    Different methodologies have evolved for consideration of each of the many steps required in performing a transportation risk analysis. Although there are techniques that attempt to consider the entire scope of the analysis in depth, most applications of risk assessment to the transportation of nuclear fuel cycle materials develop specific methodologies for only one or two parts of the analysis. The remaining steps are simplified for the analyst by narrowing the scope of the effort (such as evaluating risks for only one material, or a particular set of accident scenarios, or movement over a specific route); performing a qualitative rather than a quantitative analysis (probabilities may be simply ranked as high, medium or low, for instance); or assuming some generic, conservative conditions for potential release fractions and consequences. This paper presents a discussion of the history and present state-of-the-art of transportation risk analysis methodologies. Many reports in this area were reviewed as background for this presentation. The literature review, while not exhaustive, did result in a complete representation of the major methods used today in transportation risk analysis. These methodologies primarily include the use of severity categories based on historical accident data, the analysis of specifically assumed accident sequences for the transportation activity of interest, and the use of fault or event tree analysis. Although the focus of this work has generally been on potential impacts to public groups, some effort has been expended in the estimation of risks to occupational groups in transportation activities

  9. Bayesian Inference for NASA Probabilistic Risk and Reliability Analysis

    Science.gov (United States)

    Dezfuli, Homayoon; Kelly, Dana; Smith, Curtis; Vedros, Kurt; Galyean, William

    2009-01-01

    This document, Bayesian Inference for NASA Probabilistic Risk and Reliability Analysis, is intended to provide guidelines for the collection and evaluation of risk and reliability-related data. It is aimed at scientists and engineers familiar with risk and reliability methods and provides a hands-on approach to the investigation and application of a variety of risk and reliability data assessment methods, tools, and techniques. This document provides both: A broad perspective on data analysis collection and evaluation issues. A narrow focus on the methods to implement a comprehensive information repository. The topics addressed herein cover the fundamentals of how data and information are to be used in risk and reliability analysis models and their potential role in decision making. Understanding these topics is essential to attaining a risk informed decision making environment that is being sought by NASA requirements and procedures such as 8000.4 (Agency Risk Management Procedural Requirements), NPR 8705.05 (Probabilistic Risk Assessment Procedures for NASA Programs and Projects), and the System Safety requirements of NPR 8715.3 (NASA General Safety Program Requirements).

  10. Advanced uncertainty modelling for container port risk analysis.

    Science.gov (United States)

    Alyami, Hani; Yang, Zaili; Riahi, Ramin; Bonsall, Stephen; Wang, Jin

    2016-08-13

    Globalization has led to a rapid increase of container movements in seaports. Risks in seaports need to be appropriately addressed to ensure economic wealth, operational efficiency, and personnel safety. As a result, the safety performance of a Container Terminal Operational System (CTOS) plays a growing role in improving the efficiency of international trade. This paper proposes a novel method to facilitate the application of Failure Mode and Effects Analysis (FMEA) in assessing the safety performance of CTOS. The new approach is developed through incorporating a Fuzzy Rule-Based Bayesian Network (FRBN) with Evidential Reasoning (ER) in a complementary manner. The former provides a realistic and flexible method to describe input failure information for risk estimates of individual hazardous events (HEs) at the bottom level of a risk analysis hierarchy. The latter is used to aggregate HEs safety estimates collectively, allowing dynamic risk-based decision support in CTOS from a systematic perspective. The novel feature of the proposed method, compared to those in traditional port risk analysis lies in a dynamic model capable of dealing with continually changing operational conditions in ports. More importantly, a new sensitivity analysis method is developed and carried out to rank the HEs by taking into account their specific risk estimations (locally) and their Risk Influence (RI) to a port's safety system (globally). Due to its generality, the new approach can be tailored for a wide range of applications in different safety and reliability engineering and management systems, particularly when real time risk ranking is required to measure, predict, and improve the associated system safety performance. Copyright © 2016 Elsevier Ltd. All rights reserved.

  11. Multivariate survival analysis and competing risks

    CERN Document Server

    Crowder, Martin J

    2012-01-01

    Multivariate Survival Analysis and Competing Risks introduces univariate survival analysis and extends it to the multivariate case. It covers competing risks and counting processes and provides many real-world examples, exercises, and R code. The text discusses survival data, survival distributions, frailty models, parametric methods, multivariate data and distributions, copulas, continuous failure, parametric likelihood inference, and non- and semi-parametric methods. There are many books covering survival analysis, but very few that cover the multivariate case in any depth. Written for a graduate-level audience in statistics/biostatistics, this book includes practical exercises and R code for the examples. The author is renowned for his clear writing style, and this book continues that trend. It is an excellent reference for graduate students and researchers looking for grounding in this burgeoning field of research.

  12. Flood risk analysis procedure for nuclear power plants

    International Nuclear Information System (INIS)

    Wagner, D.P.

    1982-01-01

    This paper describes a methodology and procedure for determining the impact of floods on nuclear power plant risk. The procedures are based on techniques of fault tree and event tree analysis and use the logic of these techniques to determine the effects of a flood on system failure probability and accident sequence occurrence frequency. The methodology can be applied independently or as an add-on analysis for an existing risk assessment. Each stage of the analysis yields useful results such as the critical flood level, failure flood level, and the flood's contribution to accident sequence occurrence frequency. The results of applications show the effects of floods on the risk from nuclear power plants analyzed in the Reactor Safety Study

  13. Ontological Analysis of the Project Risk Management Concept ‘Risk’

    Directory of Open Access Journals (Sweden)

    Uzulāns Juris

    2018-02-01

    Full Text Available The aim of the current research series is to examine the definitions of the concept ‘risk’ and analyze the concepts used in the definitions of ‘risk’ in the sources of these definitions in order to perform the ontological analysis of the concept of ‘risk’. Ontological and epistemological analysis of the concepts in the definition of the concept ‘risk’ was used to answer the question what ‘risk’ means in project management. This investigation represents a part of the research series where the ontological, epistemological and methodological analysis of project risk is performed with the aim to improve risk registers and risk management as a whole. In the previous studies the author analyzed the concept of ‘event’ that defines the content of the concept ‘risk’. The use of ‘event’ was analyzed in different sources to find out how the concept should be used. The ontological, epistemological and methodological analysis of the definitions of the concept ‘risk’ is the theoretical foundation for risk register creation because it is possible to create complete and understandable register for the participants of the project risk management process. The author believes that the conducted research helps establish confidence that ontological analysis is the method that together with the epistemological and methodological analysis provides opportunity to perform analysis of risk management sources aimed at improving risk management. The results of the study cannot be considered sufficient for deriving valid conclusions about project risk management and developing recommendations for improving risk management with regard to the content of the risk register. For valid conclusions and recommendations, a deeper research is needed which, first of all, would analyze a larger number of sources.

  14. Risk analysis of alternative energy sources

    International Nuclear Information System (INIS)

    Kazmer, D.R.

    1982-01-01

    The author explores two points raised by Miller Spangler in a January 1981 issue: public perception of risks involving nuclear power plants relative to those of conventional plants and criteria for evaluating the way risk analyses are made. On the first point, he concludes that translating public attitudes into the experts' language of probability and risk could provide better information and understanding of both the attitudes and the risks. Viewing risk analysis methodologies as filters which help to test historical change, he suggests that the lack of information favors a lay jury approach for energy decisions. Spangler responds that Congress is an example of lay decision making, but that a lay jury, given public disinterest and polarization, would probably not improve social justice on the nuclear issue. 5 references, 4 figures

  15. The watchdog role of risk analysis

    International Nuclear Information System (INIS)

    Reijen, G. van; Vinck, W.

    1983-01-01

    The reason why the risks of large-scale technology attract more attention lies in the fact that accidents would have more disastrous results and in the fact that it is probably more attractive to study the risks of some large projects than to do the same for a greater number of smaller projects. Within this presentation there will be some opening remarks on the Role of the Commission of the European Community with regard to accident prevention. The development of the concept of quantitative risks is dealt with. This development leads to a combinded of deterministic and probabilistic methods. The presentation concludes with some critical remarks on quantitative risk analysis and its use. (orig./HP) [de

  16. The use of current risk analysis tools evaluated towards preventing external domino accidents

    NARCIS (Netherlands)

    Reniers, Genserik L L; Dullaert, W.; Ale, B. J.M.; Soudan, K.

    Risk analysis is an essential tool for company safety policy. Risk analysis consists of identifying and evaluating all possible risks. The efficiency of risk analysis tools depends on the rigueur of identifying and evaluating all possible risks. The diversity in risk analysis procedures is such that

  17. Dietary patterns and depression risk: A meta-analysis.

    Science.gov (United States)

    Li, Ye; Lv, Mei-Rong; Wei, Yan-Jin; Sun, Ling; Zhang, Ji-Xiang; Zhang, Huai-Guo; Li, Bin

    2017-07-01

    Although some studies have reported potential associations of dietary patterns with depression risk, a consistent perspective hasn't been estimated to date. Therefore, we conducted this meta-analysis to evaluate the relation between dietary patterns and the risk of depression. A literature research was conducted searching MEDLINE and EMBASE databases up to September 2016. In total, 21 studies from ten countries met the inclusion criteria and were included in the present meta-analysis. A dietary pattern characterized by a high intakes of fruit, vegetables, whole grain, fish, olive oil, low-fat dairy and antioxidants and low intakes of animal foods was apparently associated with a decreased risk of depression. A dietary pattern characterized by a high consumption of red and/or processed meat, refined grains, sweets, high-fat dairy products, butter, potatoes and high-fat gravy, and low intakes of fruits and vegetables is associated with an increased risk of depression. The results of this meta-analysis suggest that healthy pattern may decrease the risk of depression, whereas western-style may increase the risk of depression. However, more randomized controlled trails and cohort studies are urgently required to confirm this findings. Copyright © 2017 Elsevier Ireland Ltd. All rights reserved.

  18. Benefit-Risk Analysis for Decision-Making: An Approach.

    Science.gov (United States)

    Raju, G K; Gurumurthi, K; Domike, R

    2016-12-01

    The analysis of benefit and risk is an important aspect of decision-making throughout the drug lifecycle. In this work, the use of a benefit-risk analysis approach to support decision-making was explored. The proposed approach builds on the qualitative US Food and Drug Administration (FDA) approach to include a more explicit analysis based on international standards and guidance that enables aggregation and comparison of benefit and risk on a common basis and a lifecycle focus. The approach is demonstrated on six decisions over the lifecycle (e.g., accelerated approval, withdrawal, and traditional approval) using two case studies: natalizumab for multiple sclerosis (MS) and bedaquiline for multidrug-resistant tuberculosis (MDR-TB). © 2016 American Society for Clinical Pharmacology and Therapeutics.

  19. Methodology for risk-based analysis of technical specifications

    International Nuclear Information System (INIS)

    Vesely, W.E.; Gaertner, J.P.; Wagner, D.P.

    1985-01-01

    Part of the effort by EPRI to apply probabilistic risk assessment methods and results to the solution of utility problems involves the investigation of methods for risk-based analysis of technical specifications. The culmination of this investigation is the SOCRATES computer code developed by Battelle's Columbus Laboratories to assist in the evaluation of technical specifications of nuclear power plants. The program is designed to use information found in PRAs to re-evaluate risk for changes in component allowed outage times (AOTs) and surveillance test intervals (STIs). The SOCRATES program is a unique and important tool for technical specification evaluations. The detailed component unavailability model allows a detailed analysis of AOT and STI contributions to risk. Explicit equations allow fast and inexpensive calculations. Because the code is designed to accept ranges of parameters and to save results of calculations that do not change during the analysis, sensitivity studies are efficiently performed and results are clearly displayed

  20. Implementing the Bayesian paradigm in risk analysis

    International Nuclear Information System (INIS)

    Aven, T.; Kvaloey, J.T.

    2002-01-01

    The Bayesian paradigm comprises a unified and consistent framework for analyzing and expressing risk. Yet, we see rather few examples of applications where the full Bayesian setting has been adopted with specifications of priors of unknown parameters. In this paper, we discuss some of the practical challenges of implementing Bayesian thinking and methods in risk analysis, emphasizing the introduction of probability models and parameters and associated uncertainty assessments. We conclude that there is a need for a pragmatic view in order to 'successfully' apply the Bayesian approach, such that we can do the assignments of some of the probabilities without adopting the somewhat sophisticated procedure of specifying prior distributions of parameters. A simple risk analysis example is presented to illustrate ideas

  1. Estimated general population control limits for unitary agents in drinking water, milk, soil, and unprocessed food items. For use in reentry decision-making

    Energy Technology Data Exchange (ETDEWEB)

    Watson, A.P.; Adams, J.D.; Cerar, R.J.; Hess, T.L.; Kistner, S.L.; Leffingwell, S.S.; MacIntosh, R.G.; Ward, J.R.

    1992-01-01

    In the event of an unplanned release of chemical agent during any stage of the Chemical Stockpile Disposal Program (CSDP), the potential exists for contamination of drinking water, forage crops, grains, garden produce, and livestock. Persistent agents such as VX or sulfur mustard pose the greatest human health concern for reentry. This White Paper has been prepared to provide technical bases for these decisions by developing working estimates of agent control limits in selected environmental media considered principal sources of potential human exposure. To date, control limits for public exposure to unitary agents have been established for atmospheric concentrations only. The current analysis builds on previous work to calculate working estimates of control limits for ingestion and dermal exposure to potentially contaminated drinking water, milk, soil, and unprocessed food items such as garden produce. Information characterizing agent desorption from, and detection on or in, contaminated porous media are presently too developed to permit reasonable estimation of dermal exposure from this source. Thus, dermal contact with potentially contaminated porous surfaces is not considered in this document.

  2. Quantitative Risk Analysis: Method And Process

    Directory of Open Access Journals (Sweden)

    Anass BAYAGA

    2010-03-01

    Full Text Available Recent and past studies (King III report, 2009: 73-75; Stoney 2007;Committee of Sponsoring Organisation-COSO, 2004, Bartell, 2003; Liebenberg and Hoyt, 2003; Reason, 2000; Markowitz 1957 lament that although, the introduction of quantifying risk to enhance degree of objectivity in finance for instance was quite parallel to its development in the manufacturing industry, it is not the same in Higher Education Institution (HEI. In this regard, the objective of the paper was to demonstrate the methods and process of Quantitative Risk Analysis (QRA through likelihood of occurrence of risk (phase I. This paper serves as first of a two-phased study, which sampled hundred (100 risk analysts in a University in the greater Eastern Cape Province of South Africa.The analysis of likelihood of occurrence of risk by logistic regression and percentages were conducted to investigate whether there were a significant difference or not between groups (analyst in respect of QRA.The Hosmer and Lemeshow test was non-significant with a chi-square(X2 =8.181; p = 0.300, which indicated that there was a good model fit, since the data did not significantly deviate from the model. The study concluded that to derive an overall likelihood rating that indicated the probability that a potential risk may be exercised within the construct of an associated threat environment, the following governing factors must be considered: (1 threat source motivation and capability (2 nature of the vulnerability (3 existence and effectiveness of current controls (methods and process.

  3. Risk Analysis for Performance Improvement in a Romanian Pharmaceutical Company

    Directory of Open Access Journals (Sweden)

    Dana Corina Deselnicu

    2018-05-01

    Full Text Available The paper presents risk management analysis carried out to investigate the operations of a Romanian company dealing with the distribution of pharmaceutical products. The main risks challenging the company were identified, described and classified, providing a scientific base for further analysis. Then, the identified inherent risks were evaluated using tools as the risk index method and the risk matrix in order to emphasize their tolerance level. According to the results of the evaluation, risk mitigation strategies and measures were advanced for the management of the analysed risks. Relevant conclusions were drawn from the experience.

  4. Risk analysis and reliability

    International Nuclear Information System (INIS)

    Uppuluri, V.R.R.

    1979-01-01

    Mathematical foundations of risk analysis are addressed. The importance of having the same probability space in order to compare different experiments is pointed out. Then the following topics are discussed: consequences as random variables with infinite expectations; the phenomenon of rare events; series-parallel systems and different kinds of randomness that could be imposed on such systems; and the problem of consensus of estimates of expert opinion

  5. Assessment report on NRP sub-theme 'Risk Analysis'

    International Nuclear Information System (INIS)

    Biesiot, W.; Hendrickx, L.; Olsthoorn, A.A.

    1995-01-01

    An overview and assessment are presented of the three research projects carried out under NRP funding that concern risk-related topics: (1) The risks of nonlinear climate changes, (2) Socio-economic and policy aspects of changes in incidence and intensity of extreme (weather) events, and (3) Characterizing the risks: a comparative analysis of the risks of global warming and of relevant policy strategies. 1 tab., 6 refs

  6. Applications of probabilistic risk analysis in nuclear criticality safety design

    International Nuclear Information System (INIS)

    Chang, J.K.

    1992-01-01

    Many documents have been prepared that try to define the scope of the criticality analysis and that suggest adding probabilistic risk analysis (PRA) to the deterministic safety analysis. The report of the US Department of Energy (DOE) AL 5481.1B suggested that an accident is credible if the occurrence probability is >1 x 10 -6 /yr. The draft DOE 5480 safety analysis report suggested that safety analyses should include the application of methods such as deterministic safety analysis, risk assessment, reliability engineering, common-cause failure analysis, human reliability analysis, and human factor safety analysis techniques. The US Nuclear Regulatory Commission (NRC) report NRC SG830.110 suggested that major safety analysis methods should include but not be limited to risk assessment, reliability engineering, and human factor safety analysis. All of these suggestions have recommended including PRA in the traditional criticality analysis

  7. GIS risk analysis of hazardous materials transport

    International Nuclear Information System (INIS)

    Anders, C.; Olsten, J.

    1991-01-01

    The Geographic Information System (GIS) was used to assess the risks and vulnerability of transporting hazardous materials and wastes (such as gasoline, explosives, poisons, etc) on the Arizona highway system. This paper discusses the methodology that was utilized, and the application of GIS systems to risk analysis problems

  8. APPROPRIATE ALLOCATION OF CONTINGENCY USING RISK ANALYSIS METHODOLOGY

    Directory of Open Access Journals (Sweden)

    Andi Andi

    2004-01-01

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

  9. The integration methods of fuzzy fault mode and effect analysis and fault tree analysis for risk analysis of yogurt production

    Science.gov (United States)

    Aprilia, Ayu Rizky; Santoso, Imam; Ekasari, Dhita Murita

    2017-05-01

    Yogurt is a product based on milk, which has beneficial effects for health. The process for the production of yogurt is very susceptible to failure because it involves bacteria and fermentation. For an industry, the risks may cause harm and have a negative impact. In order for a product to be successful and profitable, it requires the analysis of risks that may occur during the production process. Risk analysis can identify the risks in detail and prevent as well as determine its handling, so that the risks can be minimized. Therefore, this study will analyze the risks of the production process with a case study in CV.XYZ. The method used in this research is the Fuzzy Failure Mode and Effect Analysis (fuzzy FMEA) and Fault Tree Analysis (FTA). The results showed that there are 6 risks from equipment variables, raw material variables, and process variables. Those risks include the critical risk, which is the risk of a lack of an aseptic process, more specifically if starter yogurt is damaged due to contamination by fungus or other bacteria and a lack of sanitation equipment. The results of quantitative analysis of FTA showed that the highest probability is the probability of the lack of an aseptic process, with a risk of 3.902%. The recommendations for improvement include establishing SOPs (Standard Operating Procedures), which include the process, workers, and environment, controlling the starter of yogurt and improving the production planning and sanitation equipment using hot water immersion.

  10. Analysis of risk factors for persistent infection of asymptomatic women with high-risk human papilloma virus.

    Science.gov (United States)

    Shi, Nianmin; Lu, Qiang; Zhang, Jiao; Li, Li; Zhang, Junnan; Zhang, Fanglei; Dong, Yanhong; Zhang, Xinyue; Zhang, Zheng; Gao, Wenhui

    2017-06-03

    This study aims to prevent persistentinfection, reduce the incidence of cervical cancer, and improve women's health by understanding the theoretical basis of the risk factors for continuous infection of asymptomatic women with high-risk human papilloma virus (HPV) strains via information collected, which includes the persistent infection rate and the most prevalent HPV strain types of high risk to asymptomatic women in the high-risk area of cervical cancer in Linfen, Shanxi Province. Based on the method of cluster sampling, locations were chosen from the industrial county and agricultural county of Linfen, Shanxi Province, namely the Xiangfen and Quwo counties. Use of the convenience sampling (CS) method enables the identification of women who have sex but without symptoms of abnormal cervix for analyzing risk factors of HPV-DNA detection and performing a retrospective questionnaire survey in these 2 counties. Firstly, cervical exfoliated cell samples were collected for thin-layer liquid-based cytology test (TCT), and simultaneously testing high-risk type HPV DNA, then samples with positive testing results were retested to identify the infected HPV types. The 6-month period of testing was done to derive the 6-month persistent infection rate. The retrospective survey included concepts addressed in the questionnaire: basic situation of the research objects, menstrual history, marital status, pregnancy history, sexual habits and other aspects. The questionnaire was divided into a case group and a comparison group, which are based on the high-risk HPV-DNA testing result to ascertain whether or not there is persistent infection. Statistical analysis employed Epidate3.1 software for date entry, SPSS17.0 for date statistical analysis. Select statistic charts, Chi-Square Analysis, single-factor analysis and multivariate Logistic regression analysis to analyze the protective factors and risk factors of high-risk HPV infection. Risk factors are predicted by using the

  11. Fault-tolerant control with mixed aerodynamic surfaces and RCS jets for hypersonic reentry vehicles

    Directory of Open Access Journals (Sweden)

    Jingjing He

    2017-04-01

    Full Text Available This paper proposes a fault-tolerant strategy for hypersonic reentry vehicles with mixed aerodynamic surfaces and reaction control systems (RCS under external disturbances and subject to actuator faults. Aerodynamic surfaces are treated as the primary actuator in normal situations, and they are driven by a continuous quadratic programming (QP allocator to generate torque commanded by a nonlinear adaptive feedback control law. When aerodynamic surfaces encounter faults, they may not be able to provide sufficient torque as commanded, and RCS jets are activated to augment the aerodynamic surfaces to compensate for insufficient torque. Partial loss of effectiveness and stuck faults are considered in this paper, and observers are designed to detect and identify the faults. Based on the fault identification results, an RCS control allocator using integer linear programming (ILP techniques is designed to determine the optimal combination of activated RCS jets. By treating the RCS control allocator as a quantization element, closed-loop stability with both continuous and quantized inputs is analyzed. Simulation results verify the effectiveness of the proposed method.

  12. Active disturbance rejection based trajectory linearization control for hypersonic reentry vehicle with bounded uncertainties.

    Science.gov (United States)

    Shao, Xingling; Wang, Honglun

    2015-01-01

    This paper investigates a novel compound control scheme combined with the advantages of trajectory linearization control (TLC) and alternative active disturbance rejection control (ADRC) for hypersonic reentry vehicle (HRV) attitude tracking system with bounded uncertainties. Firstly, in order to overcome actuator saturation problem, nonlinear tracking differentiator (TD) is applied in the attitude loop to achieve fewer control consumption. Then, linear extended state observers (LESO) are constructed to estimate the uncertainties acting on the LTV system in the attitude and angular rate loop. In addition, feedback linearization (FL) based controllers are designed using estimates of uncertainties generated by LESO in each loop, which enable the tracking error for closed-loop system in the presence of large uncertainties to converge to the residual set of the origin asymptotically. Finally, the compound controllers are derived by integrating with the nominal controller for open-loop nonlinear system and FL based controller. Also, comparisons and simulation results are presented to illustrate the effectiveness of the control strategy. Copyright © 2014 ISA. Published by Elsevier Ltd. All rights reserved.

  13. The application of CFD to hydrogen risk analysis in nuclear power plants

    International Nuclear Information System (INIS)

    Wang Hui; Han Xu; Chang Meng; Wang Xiaofeng; Wang Shuguo; Lu Xinhua; Wu Lin

    2013-01-01

    Status of the hydrogen risk analysis method is systemically summarized in this paper and the advantages and limits of CFD (Computational Fluid Dynamic) in hydrogen risk analysis is discussed. The international experimental programs on the CFD hydrogen risk analysis are introduced in this paper. The application of CFD to nuclear power plant (NPP) hydrogen risk analysis is introduced in detail by taking EPR and Ling'ao NPP for example. In these bases, the CFD development prospect of hydrogen risk analysis is also summarized in this paper. (authors)

  14. A free and open source QGIS plugin for flood risk analysis: FloodRisk

    Science.gov (United States)

    Albano, Raffaele; Sole, Aurelia; Mancusi, Leonardo

    2016-04-01

    An analysis of global statistics shows a substantial increase in flood damage over the past few decades. Moreover, it is expected that flood risk will continue to rise due to the combined effect of increasing numbers of people and economic assets in risk-prone areas and the effects of climate change. In order to increase the resilience of European economies and societies, the improvement of risk assessment and management has been pursued in the last years. This results in a wide range of flood analysis models of different complexities with substantial differences in underlying components needed for its implementation, as geographical, hydrological and social differences demand specific approaches in the different countries. At present, it is emerging the need of promote the creation of open, transparent, reliable and extensible tools for a comprehensive, context-specific and applicable flood risk analysis. In this context, the free and open-source Quantum GIS (QGIS) plugin "FloodRisk" is a good starting point to address this objective. The vision of the developers of this free and open source software (FOSS) is to combine the main features of state-of-the-art science, collaboration, transparency and interoperability in an initiative to assess and communicate flood risk worldwide and to assist authorities to facilitate the quality and fairness of flood risk management at multiple scales. Among the scientific community, this type of activity can be labelled as "participatory research", intended as adopting a set of techniques that "are interactive and collaborative" and reproducible, "providing a meaningful research experience that both promotes learning and generates knowledge and research data through a process of guided discovery"' (Albano et al., 2015). Moreover, this FOSS geospatial approach can lowering the financial barriers to understanding risks at national and sub-national levels through a spatio-temporal domain and can provide better and more complete

  15. Chemical risk evaluation, importance of the risk analysis framework uses: Latin America development restrictions

    International Nuclear Information System (INIS)

    Carrillo, M.

    2013-01-01

    The power point presentation is about reach and results of the risk analysis in Venezuela, chemical dangers in food, human damage, injuries , technologies news in fodd development, toxicity, microbiological risk, technical recommendations

  16. Spent fuel pool risk analysis for the Dukovany NPP

    Energy Technology Data Exchange (ETDEWEB)

    Hust' ak, S.; Jaros, M.; Kubicek, J. [UJV Rez, a.s., Husinec-Rez (Czech Republic)

    2013-07-01

    UJV Rez, a.s. maintains a Living Probabilistic Safety Assessment (Living PSA) program for Dukovany Nuclear Power Plant (NPP) in the Czech Republic. This project has been established as a framework for activities related to risk assessment and to support for risk-informed decision making at this plant. The most extensively used PSA application at Dukovany NPP is risk monitoring of instantaneous (point-in-time) risk during plant operation, especially for the purpose of configuration risk management during plant scheduled outages to avoid risk significant configurations. The scope of PSA for Dukovany NPP includes also determination of a risk contribution from spent fuel pool (SFP) operation to provide recommendations for the prevention and mitigation of SFP accidents and to be applicable for configuration risk management. This paper describes the analysis of internal initiating events (IEs) in PSA for Dukovany NPP, which can contribute to the risk from SFP operation. The analysis of those IEs was done more thoroughly in the PSA for Dukovany NPP in order to be used in instantaneous risk monitoring. (orig.)

  17. New risk metrics and mathematical tools for risk analysis: Current and future challenges

    International Nuclear Information System (INIS)

    Skandamis, Panagiotis N.; Andritsos, Nikolaos; Psomas, Antonios; Paramythiotis, Spyridon

    2015-01-01

    The current status of the food safety supply world wide, has led Food and Agriculture Organization (FAO) and World Health Organization (WHO) to establishing Risk Analysis as the single framework for building food safety control programs. A series of guidelines and reports that detail out the various steps in Risk Analysis, namely Risk Management, Risk Assessment and Risk Communication is available. The Risk Analysis approach enables integration between operational food management systems, such as Hazard Analysis Critical Control Points, public health and governmental decisions. To do that, a series of new Risk Metrics has been established as follows: i) the Appropriate Level of Protection (ALOP), which indicates the maximum numbers of illnesses in a population per annum, defined by quantitative risk assessments, and used to establish; ii) Food Safety Objective (FSO), which sets the maximum frequency and/or concentration of a hazard in a food at the time of consumption that provides or contributes to the ALOP. Given that ALOP is rather a metric of the public health tolerable burden (it addresses the total ‘failure’ that may be handled at a national level), it is difficult to be interpreted into control measures applied at the manufacturing level. Thus, a series of specific objectives and criteria for performance of individual processes and products have been established, all of them assisting in the achievement of FSO and hence, ALOP. In order to achieve FSO, tools quantifying the effect of processes and intrinsic properties of foods on survival and growth of pathogens are essential. In this context, predictive microbiology and risk assessment have offered an important assistance to Food Safety Management. Predictive modelling is the basis of exposure assessment and the development of stochastic and kinetic models, which are also available in the form of Web-based applications, e.g., COMBASE and Microbial Responses Viewer), or introduced into user

  18. New risk metrics and mathematical tools for risk analysis: Current and future challenges

    Energy Technology Data Exchange (ETDEWEB)

    Skandamis, Panagiotis N., E-mail: pskan@aua.gr; Andritsos, Nikolaos, E-mail: pskan@aua.gr; Psomas, Antonios, E-mail: pskan@aua.gr; Paramythiotis, Spyridon, E-mail: pskan@aua.gr [Laboratory of Food Quality Control and Hygiene, Department of Food Science and Technology, Agricultural University of Athens, Iera Odos 75, 118 55, Athens (Greece)

    2015-01-22

    The current status of the food safety supply world wide, has led Food and Agriculture Organization (FAO) and World Health Organization (WHO) to establishing Risk Analysis as the single framework for building food safety control programs. A series of guidelines and reports that detail out the various steps in Risk Analysis, namely Risk Management, Risk Assessment and Risk Communication is available. The Risk Analysis approach enables integration between operational food management systems, such as Hazard Analysis Critical Control Points, public health and governmental decisions. To do that, a series of new Risk Metrics has been established as follows: i) the Appropriate Level of Protection (ALOP), which indicates the maximum numbers of illnesses in a population per annum, defined by quantitative risk assessments, and used to establish; ii) Food Safety Objective (FSO), which sets the maximum frequency and/or concentration of a hazard in a food at the time of consumption that provides or contributes to the ALOP. Given that ALOP is rather a metric of the public health tolerable burden (it addresses the total ‘failure’ that may be handled at a national level), it is difficult to be interpreted into control measures applied at the manufacturing level. Thus, a series of specific objectives and criteria for performance of individual processes and products have been established, all of them assisting in the achievement of FSO and hence, ALOP. In order to achieve FSO, tools quantifying the effect of processes and intrinsic properties of foods on survival and growth of pathogens are essential. In this context, predictive microbiology and risk assessment have offered an important assistance to Food Safety Management. Predictive modelling is the basis of exposure assessment and the development of stochastic and kinetic models, which are also available in the form of Web-based applications, e.g., COMBASE and Microbial Responses Viewer), or introduced into user

  19. New risk metrics and mathematical tools for risk analysis: Current and future challenges

    Science.gov (United States)

    Skandamis, Panagiotis N.; Andritsos, Nikolaos; Psomas, Antonios; Paramythiotis, Spyridon

    2015-01-01

    The current status of the food safety supply world wide, has led Food and Agriculture Organization (FAO) and World Health Organization (WHO) to establishing Risk Analysis as the single framework for building food safety control programs. A series of guidelines and reports that detail out the various steps in Risk Analysis, namely Risk Management, Risk Assessment and Risk Communication is available. The Risk Analysis approach enables integration between operational food management systems, such as Hazard Analysis Critical Control Points, public health and governmental decisions. To do that, a series of new Risk Metrics has been established as follows: i) the Appropriate Level of Protection (ALOP), which indicates the maximum numbers of illnesses in a population per annum, defined by quantitative risk assessments, and used to establish; ii) Food Safety Objective (FSO), which sets the maximum frequency and/or concentration of a hazard in a food at the time of consumption that provides or contributes to the ALOP. Given that ALOP is rather a metric of the public health tolerable burden (it addresses the total `failure' that may be handled at a national level), it is difficult to be interpreted into control measures applied at the manufacturing level. Thus, a series of specific objectives and criteria for performance of individual processes and products have been established, all of them assisting in the achievement of FSO and hence, ALOP. In order to achieve FSO, tools quantifying the effect of processes and intrinsic properties of foods on survival and growth of pathogens are essential. In this context, predictive microbiology and risk assessment have offered an important assistance to Food Safety Management. Predictive modelling is the basis of exposure assessment and the development of stochastic and kinetic models, which are also available in the form of Web-based applications, e.g., COMBASE and Microbial Responses Viewer), or introduced into user-friendly softwares

  20. Risk analysis for decision support in electricity distribution system asset management: methods and frameworks for analysing intangible risks

    Energy Technology Data Exchange (ETDEWEB)

    Nordgaard, Dag Eirik

    2010-04-15

    During the last 10 to 15 years electricity distribution companies throughout the world have been ever more focused on asset management as the guiding principle for their activities. Within asset management, risk is a key issue for distribution companies, together with handling of cost and performance. There is now an increased awareness of the need to include risk analyses into the companies' decision making processes. Much of the work on risk in electricity distribution systems has focused on aspects of reliability. This is understandable, since it is surely an important feature of the product delivered by the electricity distribution infrastructure, and it is high on the agenda for regulatory authorities in many countries. However, electricity distribution companies are also concerned with other risks relevant for their decision making. This typically involves intangible risks, such as safety, environmental impacts and company reputation. In contrast to the numerous methodologies developed for reliability risk analysis, there are relatively few applications of structured analyses to support decisions concerning intangible risks, even though they represent an important motivation for decisions taken in electricity distribution companies. The overall objective of this PhD work has been to explore risk analysis methods that can be used to improve and support decision making in electricity distribution system asset management, with an emphasis on the analysis of intangible risks. The main contributions of this thesis can be summarised as: An exploration and testing of quantitative risk analysis (QRA) methods to support decisions concerning intangible risks; The development of a procedure for using life curve models to provide input to QRA models; The development of a framework for risk-informed decision making where QRA are used to analyse selected problems; In addition, the results contribute to clarify the basic concepts of risk, and highlight challenges

  1. 再突入飛行体まわりの空力加熱のCFD解析と実験

    OpenAIRE

    Yamamoto, Yukimitsu; 山本 行光

    1997-01-01

    Recent comparisons of hypersonic CFD (Computational Fluid Dynamics) analysis with hypersonic wind tunnel experiments, including NAL M10 HWT (Hypersonic Wind Tunnel), ONERA S4MA HWT, Calspan's shock tunnel and Caltech T-5 high enthalpy shock tunnel, are introduced. Also, hypersonic reentry flight analysis, such as OREX (Orbital Reentry Experiment) and HYFLEX (Hypersonic Flight Experiment) are made. Through these studies, aerothermodynamic heating characteristics of reentry vehicle are investig...

  2. [Reliability theory based on quality risk network analysis for Chinese medicine injection].

    Science.gov (United States)

    Li, Zheng; Kang, Li-Yuan; Fan, Xiao-Hui

    2014-08-01

    A new risk analysis method based upon reliability theory was introduced in this paper for the quality risk management of Chinese medicine injection manufacturing plants. The risk events including both cause and effect ones were derived in the framework as nodes with a Bayesian network analysis approach. It thus transforms the risk analysis results from failure mode and effect analysis (FMEA) into a Bayesian network platform. With its structure and parameters determined, the network can be used to evaluate the system reliability quantitatively with probabilistic analytical appraoches. Using network analysis tools such as GeNie and AgenaRisk, we are able to find the nodes that are most critical to influence the system reliability. The importance of each node to the system can be quantitatively evaluated by calculating the effect of the node on the overall risk, and minimization plan can be determined accordingly to reduce their influences and improve the system reliability. Using the Shengmai injection manufacturing plant of SZYY Ltd as a user case, we analyzed the quality risk with both static FMEA analysis and dynamic Bayesian Network analysis. The potential risk factors for the quality of Shengmai injection manufacturing were identified with the network analysis platform. Quality assurance actions were further defined to reduce the risk and improve the product quality.

  3. Crime, violence, and behavioral health: collaborative community strategies for risk mitigation.

    Science.gov (United States)

    Pinals, Debra A

    2015-06-01

    Criminal conduct is not always violent, and violence does not always lead to criminal charges. Moreover, crime and violence have multifaceted etiologies. Most violence in society is not attributable to mental illness. Where there is a small relationship between violence and mental illness, the risk of violence increases for individuals with substance use histories. Underlying trauma can also play a role. Antisocial attitudes, behaviors, and peer groups further increase the risk that individuals, including those with mental illness, will find themselves at risk of criminal recidivism. Criminal histories among public mental health populations, and mental health and substance use disorders among criminal populations are each higher than general population comparisons. Care within behavioral health settings should therefore target decreased criminal recidivism and decreased violence as part of recovery for those individuals at risk, using trauma-informed approaches and peer supports. Interventions that show promise bring criminal justice and behavioral health systems together, and include police-based diversion, specialty courts, court-based alternatives to incarceration, and coordinated re-entry programs. This article reviews these options along with specific risk management strategies, such as using risk, needs, and responsivity factors as a means of improving overall outcomes for persons with mental illness, while minimizing their risk of further criminalization and victimization.

  4. Dietary patterns and colorectal cancer risk: a meta-analysis.

    Science.gov (United States)

    Feng, Yu-Liang; Shu, Long; Zheng, Pei-Fen; Zhang, Xiao-Yan; Si, Cai-Juan; Yu, Xiao-Long; Gao, Wei; Zhang, Lun

    2017-05-01

    The analysis of dietary patterns has recently drawn considerable attention as a method of investigating the association between the overall whole diet and the risk of colorectal cancer. However, the results have yielded conflicting findings. Here, we carried out a meta-analysis to identify the association between dietary patterns and the risk of colorectal cancer. A total of 40 studies fulfilled the inclusion criteria and were included in this meta-analysis. The highest category of 'healthy' dietary pattern compared with the lowest category was apparently associated with a decreased risk for colorectal cancer [odds ratio (OR)=0.75; confidence interval (CI): 0.68-0.83; Pcolorectal cancer was shown for the highest compared with the lowest category of a 'western-style' dietary pattern (OR=1.40; CI: 1.26-1.56; Pcolorectal cancer in the highest compared with the lowest category of 'alcohol-consumption' pattern (OR=1.44; CI: 1.13-1.82; P=0.003). The results of this meta-analysis indicate that a 'healthy' dietary pattern may decrease the risk of colorectal cancer, whereas 'western-style' and 'alcohol-consumption' patterns may increase the risk of colorectal cancer.

  5. Sensitivity Analysis of Launch Vehicle Debris Risk Model

    Science.gov (United States)

    Gee, Ken; Lawrence, Scott L.

    2010-01-01

    As part of an analysis of the loss of crew risk associated with an ascent abort system for a manned launch vehicle, a model was developed to predict the impact risk of the debris resulting from an explosion of the launch vehicle on the crew module. The model consisted of a debris catalog describing the number, size and imparted velocity of each piece of debris, a method to compute the trajectories of the debris and a method to calculate the impact risk given the abort trajectory of the crew module. The model provided a point estimate of the strike probability as a function of the debris catalog, the time of abort and the delay time between the abort and destruction of the launch vehicle. A study was conducted to determine the sensitivity of the strike probability to the various model input parameters and to develop a response surface model for use in the sensitivity analysis of the overall ascent abort risk model. The results of the sensitivity analysis and the response surface model are presented in this paper.

  6. Supplemental Hazard Analysis and Risk Assessment - Hydrotreater

    Energy Technology Data Exchange (ETDEWEB)

    Lowry, Peter P. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Wagner, Katie A. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2015-04-01

    A supplemental hazard analysis was conducted and quantitative risk assessment performed in response to an independent review comment received by the Pacific Northwest National Laboratory (PNNL) from the U.S. Department of Energy Pacific Northwest Field Office (PNSO) against the Hydrotreater/Distillation Column Hazard Analysis Report issued in April 2013. The supplemental analysis used the hazardous conditions documented by the previous April 2013 report as a basis. The conditions were screened and grouped for the purpose of identifying whether additional prudent, practical hazard controls could be identified, using a quantitative risk evaluation to assess the adequacy of the controls and establish a lower level of concern for the likelihood of potential serious accidents. Calculations were performed to support conclusions where necessary.

  7. Revealing the underlying drivers of disaster risk: a global analysis

    Science.gov (United States)

    Peduzzi, Pascal

    2017-04-01

    Disasters events are perfect examples of compound events. Disaster risk lies at the intersection of several independent components such as hazard, exposure and vulnerability. Understanding the weight of each component requires extensive standardisation. Here, I show how footprints of past disastrous events were generated using GIS modelling techniques and used for extracting population and economic exposures based on distribution models. Using past event losses, it was possible to identify and quantify a wide range of socio-politico-economic drivers associated with human vulnerability. The analysis was applied to about nine thousand individual past disastrous events covering earthquakes, floods and tropical cyclones. Using a multiple regression analysis on these individual events it was possible to quantify each risk component and assess how vulnerability is influenced by various hazard intensities. The results show that hazard intensity, exposure, poverty, governance as well as other underlying factors (e.g. remoteness) can explain the magnitude of past disasters. Analysis was also performed to highlight the role of future trends in population and climate change and how this may impacts exposure to tropical cyclones in the future. GIS models combined with statistical multiple regression analysis provided a powerful methodology to identify, quantify and model disaster risk taking into account its various components. The same methodology can be applied to various types of risk at local to global scale. This method was applied and developed for the Global Risk Analysis of the Global Assessment Report on Disaster Risk Reduction (GAR). It was first applied on mortality risk in GAR 2009 and GAR 2011. New models ranging from global assets exposure and global flood hazard models were also recently developed to improve the resolution of the risk analysis and applied through CAPRA software to provide probabilistic economic risk assessments such as Average Annual Losses (AAL

  8. Risk analysis of heat recovery steam generator with semi quantitative risk based inspection API 581

    Science.gov (United States)

    Prayogo, Galang Sandy; Haryadi, Gunawan Dwi; Ismail, Rifky; Kim, Seon Jin

    2016-04-01

    Corrosion is a major problem that most often occurs in the power plant. Heat recovery steam generator (HRSG) is an equipment that has a high risk to the power plant. The impact of corrosion damage causing HRSG power plant stops operating. Furthermore, it could be threaten the safety of employees. The Risk Based Inspection (RBI) guidelines by the American Petroleum Institute (API) 58 has been used to risk analysis in the HRSG 1. By using this methodology, the risk that caused by unexpected failure as a function of the probability and consequence of failure can be estimated. This paper presented a case study relating to the risk analysis in the HRSG, starting with a summary of the basic principles and procedures of risk assessment and applying corrosion RBI for process industries. The risk level of each HRSG equipment were analyzed: HP superheater has a medium high risk (4C), HP evaporator has a medium-high risk (4C), and the HP economizer has a medium risk (3C). The results of the risk assessment using semi-quantitative method of standard API 581 based on the existing equipment at medium risk. In the fact, there is no critical problem in the equipment components. Damage mechanisms were prominent throughout the equipment is thinning mechanism. The evaluation of the risk approach was done with the aim of reducing risk by optimizing the risk assessment activities.

  9. Risk analysis of heat recovery steam generator with semi quantitative risk based inspection API 581

    International Nuclear Information System (INIS)

    Prayogo, Galang Sandy; Haryadi, Gunawan Dwi; Ismail, Rifky; Kim, Seon Jin

    2016-01-01

    Corrosion is a major problem that most often occurs in the power plant. Heat recovery steam generator (HRSG) is an equipment that has a high risk to the power plant. The impact of corrosion damage causing HRSG power plant stops operating. Furthermore, it could be threaten the safety of employees. The Risk Based Inspection (RBI) guidelines by the American Petroleum Institute (API) 58 has been used to risk analysis in the HRSG 1. By using this methodology, the risk that caused by unexpected failure as a function of the probability and consequence of failure can be estimated. This paper presented a case study relating to the risk analysis in the HRSG, starting with a summary of the basic principles and procedures of risk assessment and applying corrosion RBI for process industries. The risk level of each HRSG equipment were analyzed: HP superheater has a medium high risk (4C), HP evaporator has a medium-high risk (4C), and the HP economizer has a medium risk (3C). The results of the risk assessment using semi-quantitative method of standard API 581 based on the existing equipment at medium risk. In the fact, there is no critical problem in the equipment components. Damage mechanisms were prominent throughout the equipment is thinning mechanism. The evaluation of the risk approach was done with the aim of reducing risk by optimizing the risk assessment activities.

  10. Risk analysis of heat recovery steam generator with semi quantitative risk based inspection API 581

    Energy Technology Data Exchange (ETDEWEB)

    Prayogo, Galang Sandy, E-mail: gasandylang@live.com; Haryadi, Gunawan Dwi; Ismail, Rifky [Department of Mechanical Engineering, Diponegoro University, Semarang (Indonesia); Kim, Seon Jin [Department of Mechanical & Automotive Engineering of Pukyong National University (Korea, Republic of)

    2016-04-19

    Corrosion is a major problem that most often occurs in the power plant. Heat recovery steam generator (HRSG) is an equipment that has a high risk to the power plant. The impact of corrosion damage causing HRSG power plant stops operating. Furthermore, it could be threaten the safety of employees. The Risk Based Inspection (RBI) guidelines by the American Petroleum Institute (API) 58 has been used to risk analysis in the HRSG 1. By using this methodology, the risk that caused by unexpected failure as a function of the probability and consequence of failure can be estimated. This paper presented a case study relating to the risk analysis in the HRSG, starting with a summary of the basic principles and procedures of risk assessment and applying corrosion RBI for process industries. The risk level of each HRSG equipment were analyzed: HP superheater has a medium high risk (4C), HP evaporator has a medium-high risk (4C), and the HP economizer has a medium risk (3C). The results of the risk assessment using semi-quantitative method of standard API 581 based on the existing equipment at medium risk. In the fact, there is no critical problem in the equipment components. Damage mechanisms were prominent throughout the equipment is thinning mechanism. The evaluation of the risk approach was done with the aim of reducing risk by optimizing the risk assessment activities.

  11. The development of a 3D risk analysis method.

    Science.gov (United States)

    I, Yet-Pole; Cheng, Te-Lung

    2008-05-01

    Much attention has been paid to the quantitative risk analysis (QRA) research in recent years due to more and more severe disasters that have happened in the process industries. Owing to its calculation complexity, very few software, such as SAFETI, can really make the risk presentation meet the practice requirements. However, the traditional risk presentation method, like the individual risk contour in SAFETI, is mainly based on the consequence analysis results of dispersion modeling, which usually assumes that the vapor cloud disperses over a constant ground roughness on a flat terrain with no obstructions and concentration fluctuations, which is quite different from the real situations of a chemical process plant. All these models usually over-predict the hazardous regions in order to maintain their conservativeness, which also increases the uncertainty of the simulation results. On the other hand, a more rigorous model such as the computational fluid dynamics (CFD) model can resolve the previous limitations; however, it cannot resolve the complexity of risk calculations. In this research, a conceptual three-dimensional (3D) risk calculation method was proposed via the combination of results of a series of CFD simulations with some post-processing procedures to obtain the 3D individual risk iso-surfaces. It is believed that such technique will not only be limited to risk analysis at ground level, but also be extended into aerial, submarine, or space risk analyses in the near future.

  12. Analysis of Alternatives for Risk Assessment Methodologies and Tools

    Energy Technology Data Exchange (ETDEWEB)

    Nachtigal, Noel M. [Sandia National Lab. (SNL-CA), Livermore, CA (United States). System Analytics; Fruetel, Julia A. [Sandia National Lab. (SNL-CA), Livermore, CA (United States). Systems Research and Analysis; Gleason, Nathaniel J. [Sandia National Lab. (SNL-CA), Livermore, CA (United States). Systems Research and Analysis; Helms, Jovana [Sandia National Lab. (SNL-CA), Livermore, CA (United States). Systems Research and Analysis; Imbro, Dennis Raymond [Sandia National Lab. (SNL-CA), Livermore, CA (United States). Systems Research and Analysis; Sumner, Matthew C. [Sandia National Lab. (SNL-CA), Livermore, CA (United States). Systems Research and Analysis

    2013-10-01

    The purpose of this document is to provide a basic overview and understanding of risk assessment methodologies and tools from the literature and to assess the suitability of these methodologies and tools for cyber risk assessment. Sandia National Laboratories (SNL) performed this review in support of risk modeling activities performed for the Stakeholder Engagement and Cyber Infrastructure Resilience (SECIR) division of the Department of Homeland Security (DHS) Office of Cybersecurity and Communications (CS&C). The set of methodologies and tools covered in this document is not intended to be exhaustive; instead, it focuses on those that are commonly used in the risk assessment community. The classification of methodologies and tools was performed by a group of analysts with experience in risk analysis and cybersecurity, and the resulting analysis of alternatives has been tailored to address the needs of a cyber risk assessment.

  13. Comparative risk analysis for the Rocky Flats Plant integrated project planning

    International Nuclear Information System (INIS)

    Jones, M.E.; Shain, D.I.

    1994-01-01

    The Rocky Flats Plant is developing, with active stakeholder a comprehensive planning strategy that will support transition of the Rocky Flats Plant from a nuclear weapons production facility to site cleanup and final disposition. Final disposition of the Rocky Flats Plant materials and contaminants requires consideration of the interrelated nature of sitewide problems, such as material movement and disposition, facility and land use endstates, costs relative risks to workers and the public, and waste disposition. Comparative Risk Analysis employs both incremental risk and cumulative risk evaluations to compare risks from postulated options or endstates. These postulated options or endstates can be various remedial alternatives, or future endstate uses of federal agency land. Currently, there does not exist any approved methodology that aggregates various incremental risk estimates. Comparative Risk Analysis has been developed to aggregate various incremental risk estimates to develop a site cumulative risk estimate. This paper discusses development of the Comparative Risk Analysis methodology, stakeholder participation and lessons learned from these challenges

  14. POPSCAN: A CNES Geo-Information Study for Re-Entry Risk Assessment

    Science.gov (United States)

    Fuentes, N.; Tholey, N.; Battiston, S.; Montabord, M.; Studer, M.

    2013-09-01

    Within the framework of the FSOA, French Space Operations Act (referred to as the "Loi relative aux Opérations Spatiales" or LOS in French), including in particular the monitoring of safety requirements for people and property, one major parameter to consider is Geographic Information (GI) on population distribution, human activity, and land occupation.This article gives an overview of the set of geographic and demographic data examined for CNES control offices, outlining the advantages and limits of each one : coverage, precision, update frequency, availability, distribution, ...It focuses on the two major available global population databases: GPW-GRUMP from CIESIN of COLUMBIA University and LandScan from ORNL. The work engaged on POPSCAN integrates digital analysis about these two world population grids and also comparisons on other databases such as GLOBAL- INSIGHT, VMAP0, ESRI, DMSP-ISA, GLOBCOVER, OpenFlights, ... for urban areas, communication networks, sensitive human activities and land use.

  15. Source modelling in seismic risk analysis for nuclear power plants

    International Nuclear Information System (INIS)

    Yucemen, M.S.

    1978-12-01

    The proposed probabilistic procedure provides a consistent method for the modelling, analysis and updating of uncertainties that are involved in the seismic risk analysis for nuclear power plants. The potential earthquake activity zones are idealized as point, line or area sources. For these seismic source types, expressions to evaluate their contribution to seismic risk are derived, considering all the possible site-source configurations. The seismic risk at a site is found to depend not only on the inherent randomness of the earthquake occurrences with respect to magnitude, time and space, but also on the uncertainties associated with the predicted values of the seismic and geometric parameters, as well as the uncertainty in the attenuation model. The uncertainty due to the attenuation equation is incorporated into the analysis through the use of random correction factors. The influence of the uncertainty resulting from the insufficient information on the seismic parameters and source geometry is introduced into the analysis by computing a mean risk curve averaged over the various alternative assumptions on the parameters and source geometry. Seismic risk analysis is carried for the city of Denizli, which is located in the seismically most active zone of Turkey. The second analysis is for Akkuyu

  16. The Total Risk Analysis of Large Dams under Flood Hazards

    Directory of Open Access Journals (Sweden)

    Yu Chen

    2018-02-01

    Full Text Available Dams and reservoirs are useful systems in water conservancy projects; however, they also pose a high-risk potential for large downstream areas. Flood, as the driving force of dam overtopping, is the main cause of dam failure. Dam floods and their risks are of interest to researchers and managers. In hydraulic engineering, there is a growing tendency to evaluate dam flood risk based on statistical and probabilistic methods that are unsuitable for the situations with rare historical data or low flood probability, so a more reasonable dam flood risk analysis method with fewer application restrictions is needed. Therefore, different from previous studies, this study develops a flood risk analysis method for large dams based on the concept of total risk factor (TRF used initially in dam seismic risk analysis. The proposed method is not affected by the adequacy of historical data or the low probability of flood and is capable of analyzing the dam structure influence, the flood vulnerability of the dam site, and downstream risk as well as estimating the TRF of each dam and assigning corresponding risk classes to each dam. Application to large dams in the Dadu River Basin, Southwestern China, demonstrates that the proposed method provides quick risk estimation and comparison, which can help local management officials perform more detailed dam safety evaluations for useful risk management information.

  17. Methodology for flood risk analysis for nuclear power plants

    International Nuclear Information System (INIS)

    Wagner, D.P.; Casada, M.L.; Fussell, J.B.

    1984-01-01

    The methodology for flood risk analysis described here addresses the effects of a flood on nuclear power plant safety systems. Combining the results of this method with the probability of a flood allows the effects of flooding to be included in a probabilistic risk assessment. The five-step methodology includes accident sequence screening to focus the detailed analysis efforts on the accident sequences that are significantly affected by a flood event. The quantitative results include the flood's contribution to system failure probability, accident sequence occurrence frequency and consequence category occurrence frequency. The analysis can be added to existing risk assessments without a significant loss in efficiency. The results of two example applications show the usefulness of the methodology. Both examples rely on the Reactor Safety Study for the required risk assessment inputs and present changes in the Reactor Safety Study results as a function of flood probability

  18. Investment appraisal using quantitative risk analysis.

    Science.gov (United States)

    Johansson, Henrik

    2002-07-01

    Investment appraisal concerned with investments in fire safety systems is discussed. Particular attention is directed at evaluating, in terms of the Bayesian decision theory, the risk reduction that investment in a fire safety system involves. It is shown how the monetary value of the change from a building design without any specific fire protection system to one including such a system can be estimated by use of quantitative risk analysis, the results of which are expressed in terms of a Risk-adjusted net present value. This represents the intrinsic monetary value of investing in the fire safety system. The method suggested is exemplified by a case study performed in an Avesta Sheffield factory.

  19. Gender Analysis of Risk in Innovation System

    DEFF Research Database (Denmark)

    Ayinde, Ope; Muchie, Mammo; Abaniyan, E. O.

    2011-01-01

    the new maize variety. The analytical tools used include descriptive statistics, regression model; risk utility functions and risk parameter analysis. The result showed that invasion by animals, disease and pest, lack of access to credit wind and price fluctuation were the major risk facing the maize......This study analyzed risk by gender in innovation in Kwara state, Nigeria, using downy mildew resistant maize production as case study. The study employed primary and secondary data. The primary data were collected from well-structured questionnaires administered to both male and female producing...... producers in the area in the usage of the new innovation. The study also revealed that male producers were willing to take risk in the new maize variety production than the female, while the females were more indifferent to the risk involved in the new maize production variety than males. None...

  20. Multi-Disaster Risk Analysis of Klaten Regency, Central Java, Indonesia

    Directory of Open Access Journals (Sweden)

    Candra Dian Lukita Tauhid

    2017-09-01

    Full Text Available Klaten Regency is located in Central Java Province, Indonesia, ranked as 19th most susceptible area in Indonesia. Among of many disasters those take place in Klaten are floods, landslides, and earthquake, which cause damages and loss of lives. Unfortunately, some areas in Klaten Regency are also very vulnerable to the disasters that often contribute severe damage and loss. This paper presents result of risk analysis due to floods, landslides and earthquake disaster at Klaten Regency. Several parameters or criteria are utilized to describe the level of the disaster intensities. The flood susceptibility parameters are the Topographic Wet Index (TWI, Normalized Difference Vegetation Index (NDVI, permeability and roughness, as proposed by Kafira, et al. (2015. The landslide susceptibility are the geology, slope, elevation, distance from fault, distance from rivers, rainfall and land use, as suggested by Thearith (2009 whereas the earthquake susceptibility was referred to FEMA P-154 by using the Ss and S1. The vulnerability and risk analysis are carried out by referring to the parameters as stipulated by the Chief Regulation of the National Board of Disaster Management No.2 Year 2012 (Perka Badan Nasional Penanggulangan Bencana- BNPB, concerning the parameters being used for the vulnerability analysis, i.e. population density, poverty ratio, land use, and level of Gross Regional Domestic Product. Further spatial analysis of the risk performs the multi-disaster risk map as a combination between the floods, landslides and earthquake disaster risk in Klaten Regency. The established multi-disaster risk map shows the risk level in the Klaten Regency, i.e., 16.31% at very low risk, 33.01% at low risk, 34.49% at medium risk, at 14.22% high risk and 1.97% at very high risk.

  1. Key attributes of the SAPHIRE risk and reliability analysis software for risk-informed probabilistic applications

    International Nuclear Information System (INIS)

    Smith, Curtis; Knudsen, James; Kvarfordt, Kellie; Wood, Ted

    2008-01-01

    The Idaho National Laboratory is a primary developer of probabilistic risk and reliability analysis (PRRA) tools, dating back over 35 years. Evolving from mainframe-based software, the current state-of-the-practice has led to the creation of the SAPHIRE software. Currently, agencies such as the Nuclear Regulatory Commission, the National Aeronautics and Aerospace Agency, the Department of Energy, and the Department of Defense use version 7 of the SAPHIRE software for many of their risk-informed activities. In order to better understand and appreciate the power of software as part of risk-informed applications, we need to recall that our current analysis methods and solution methods have built upon pioneering work done 30-40 years ago. We contrast this work with the current capabilities in the SAPHIRE analysis package. As part of this discussion, we provide information for both the typical features and special analysis capabilities, which are available. We also present the application and results typically found with state-of-the-practice PRRA models. By providing both a high-level and detailed look at the SAPHIRE software, we give a snapshot in time for the current use of software tools in a risk-informed decision arena

  2. A scenario-based procedure for seismic risk analysis

    International Nuclear Information System (INIS)

    Kluegel, J.-U.; Mualchin, L.; Panza, G.F.

    2006-12-01

    A new methodology for seismic risk analysis based on probabilistic interpretation of deterministic or scenario-based hazard analysis, in full compliance with the likelihood principle and therefore meeting the requirements of modern risk analysis, has been developed. The proposed methodology can easily be adjusted to deliver its output in a format required for safety analysts and civil engineers. The scenario-based approach allows the incorporation of all available information collected in a geological, seismotectonic and geotechnical database of the site of interest as well as advanced physical modelling techniques to provide a reliable and robust deterministic design basis for civil infrastructures. The robustness of this approach is of special importance for critical infrastructures. At the same time a scenario-based seismic hazard analysis allows the development of the required input for probabilistic risk assessment (PRA) as required by safety analysts and insurance companies. The scenario-based approach removes the ambiguity in the results of probabilistic seismic hazard analysis (PSHA) which relies on the projections of Gutenberg-Richter (G-R) equation. The problems in the validity of G-R projections, because of incomplete to total absence of data for making the projections, are still unresolved. Consequently, the information from G-R must not be used in decisions for design of critical structures or critical elements in a structure. The scenario-based methodology is strictly based on observable facts and data and complemented by physical modelling techniques, which can be submitted to a formalised validation process. By means of sensitivity analysis, knowledge gaps related to lack of data can be dealt with easily, due to the limited amount of scenarios to be investigated. The proposed seismic risk analysis can be used with confidence for planning, insurance and engineering applications. (author)

  3. Ontology-based specification, identification and analysis of perioperative risks.

    Science.gov (United States)

    Uciteli, Alexandr; Neumann, Juliane; Tahar, Kais; Saleh, Kutaiba; Stucke, Stephan; Faulbrück-Röhr, Sebastian; Kaeding, André; Specht, Martin; Schmidt, Tobias; Neumuth, Thomas; Besting, Andreas; Stegemann, Dominik; Portheine, Frank; Herre, Heinrich

    2017-09-06

    Medical personnel in hospitals often works under great physical and mental strain. In medical decision-making, errors can never be completely ruled out. Several studies have shown that between 50 and 60% of adverse events could have been avoided through better organization, more attention or more effective security procedures. Critical situations especially arise during interdisciplinary collaboration and the use of complex medical technology, for example during surgical interventions and in perioperative settings (the period of time before, during and after surgical intervention). In this paper, we present an ontology and an ontology-based software system, which can identify risks across medical processes and supports the avoidance of errors in particular in the perioperative setting. We developed a practicable definition of the risk notion, which is easily understandable by the medical staff and is usable for the software tools. Based on this definition, we developed a Risk Identification Ontology (RIO) and used it for the specification and the identification of perioperative risks. An agent system was developed, which gathers risk-relevant data during the whole perioperative treatment process from various sources and provides it for risk identification and analysis in a centralized fashion. The results of such an analysis are provided to the medical personnel in form of context-sensitive hints and alerts. For the identification of the ontologically specified risks, we developed an ontology-based software module, called Ontology-based Risk Detector (OntoRiDe). About 20 risks relating to cochlear implantation (CI) have already been implemented. Comprehensive testing has indicated the correctness of the data acquisition, risk identification and analysis components, as well as the web-based visualization of results.

  4. Safety analysis and risk assessment handbook

    International Nuclear Information System (INIS)

    Peterson, V.L.; Colwell, R.G.; Dickey, R.L.

    1997-01-01

    This Safety Analysis and Risk Assessment Handbook (SARAH) provides guidance to the safety analyst at the Rocky Flats Environmental Technology Site (RFETS) in the preparation of safety analyses and risk assessments. Although the older guidance (the Rocky Flats Risk Assessment Guide) continues to be used for updating the Final Safety Analysis Reports developed in the mid-1980s, this new guidance is used with all new authorization basis documents. With the mission change at RFETS came the need to establish new authorization basis documents for its facilities, whose functions had changed. The methodology and databases for performing the evaluations that support the new authorization basis documents had to be standardized, to avoid the use of different approaches and/or databases for similar accidents in different facilities. This handbook presents this new standardized approach. The handbook begins with a discussion of the requirements of the different types of authorization basis documents and how to choose the one appropriate for the facility to be evaluated. It then walks the analyst through the process of identifying all the potential hazards in the facility, classifying them, and choosing the ones that need to be analyzed further. It then discusses the methods for evaluating accident initiation and progression and covers the basic steps in a safety analysis, including consequence and frequency binning and risk ranking. The handbook lays out standardized approaches for determining the source terms of the various accidents (including airborne release fractions, leakpath factors, etc.), the atmospheric dispersion factors appropriate for Rocky Flats, and the methods for radiological and chemical consequence assessments. The radiological assessments use a radiological open-quotes templateclose quotes, a spreadsheet that incorporates the standard values of parameters, whereas the chemical assessments use the standard codes ARCHIE and ALOHA

  5. Adaptive twisting sliding mode algorithm for hypersonic reentry vehicle attitude control based on finite-time observer.

    Science.gov (United States)

    Guo, Zongyi; Chang, Jing; Guo, Jianguo; Zhou, Jun

    2018-06-01

    This paper focuses on the adaptive twisting sliding mode control for the Hypersonic Reentry Vehicles (HRVs) attitude tracking issue. The HRV attitude tracking model is transformed into the error dynamics in matched structure, whereas an unmeasurable state is redefined by lumping the existing unmatched disturbance with the angular rate. Hence, an adaptive finite-time observer is used to estimate the unknown state. Then, an adaptive twisting algorithm is proposed for systems subject to disturbances with unknown bounds. The stability of the proposed observer-based adaptive twisting approach is guaranteed, and the case of noisy measurement is analyzed. Also, the developed control law avoids the aggressive chattering phenomenon of the existing adaptive twisting approaches because the adaptive gains decrease close to the disturbance once the trajectories reach the sliding surface. Finally, numerical simulations on the attitude control of the HRV are conducted to verify the effectiveness and benefit of the proposed approach. Copyright © 2018 ISA. Published by Elsevier Ltd. All rights reserved.

  6. Integrated Risk-Capability Analysis under Deep Uncertainty : An ESDMA Approach

    NARCIS (Netherlands)

    Pruyt, E.; Kwakkel, J.H.

    2012-01-01

    Integrated risk-capability analysis methodologies for dealing with increasing degrees of complexity and deep uncertainty are urgently needed in an ever more complex and uncertain world. Although scenario approaches, risk assessment methods, and capability analysis methods are used, few organizations

  7. Risk analysis for nuclear power plants

    International Nuclear Information System (INIS)

    Koelzer, W.

    1983-01-01

    The German risk analysis program for nuclear power plants aiming at the man and the environment is presented. An accident consequence model to calculate the radiological impact and the potential health effects is described. (E.G.) [pt

  8. Risk factors for radiation-induced hypothyroidism: A Literature-Based Meta-Analysis

    DEFF Research Database (Denmark)

    Vogelius, Ivan R; Bentzen, Søren; Maraldo, Maja V

    2011-01-01

    BACKGROUND: A systematic overview and meta-analysis of studies reporting data on hypothyroidism (HT) after radiation therapy was conducted to identify risk factors for development of HT. METHODS: Published studies were identified from the PubMed and Embase databases and by hand-searching published...... reviews. Studies allowing the extraction of odds ratios (OR) for HT in 1 or more of several candidate clinical risk groups were included. A meta-analysis of the OR for development of HT with or without each of the candidate risk factors was performed. Furthermore, studies allowing the extraction......% risk of HT at a dose of 45 Gy but with considerable variation in the dose response between studies. Chemotherapy and age were not associated with risk of HT in this analysis. CONCLUSIONS: Several clinical risk factors for HT were identified. The risk of HT increases with increasing radiation dose...

  9. Approach to uncertainty in risk analysis

    Energy Technology Data Exchange (ETDEWEB)

    Rish, W.R.

    1988-08-01

    In the Fall of 1985 EPA's Office of Radiation Programs (ORP) initiated a project to develop a formal approach to dealing with uncertainties encountered when estimating and evaluating risks to human health and the environment. Based on a literature review of modeling uncertainty, interviews with ORP technical and management staff, and input from experts on uncertainty analysis, a comprehensive approach was developed. This approach recognizes by design the constraints on budget, time, manpower, expertise, and availability of information often encountered in ''real world'' modeling. It is based on the observation that in practice risk modeling is usually done to support a decision process. As such, the approach focuses on how to frame a given risk modeling problem, how to use that framing to select an appropriate mixture of uncertainty analyses techniques, and how to integrate the techniques into an uncertainty assessment that effectively communicates important information and insight to decision-makers. The approach is presented in this report. Practical guidance on characterizing and analyzing uncertainties about model form and quantities and on effectively communicating uncertainty analysis results is included. Examples from actual applications are presented.

  10. Approach to uncertainty in risk analysis

    International Nuclear Information System (INIS)

    Rish, W.R.

    1988-08-01

    In the Fall of 1985 EPA's Office of Radiation Programs (ORP) initiated a project to develop a formal approach to dealing with uncertainties encountered when estimating and evaluating risks to human health and the environment. Based on a literature review of modeling uncertainty, interviews with ORP technical and management staff, and input from experts on uncertainty analysis, a comprehensive approach was developed. This approach recognizes by design the constraints on budget, time, manpower, expertise, and availability of information often encountered in ''real world'' modeling. It is based on the observation that in practice risk modeling is usually done to support a decision process. As such, the approach focuses on how to frame a given risk modeling problem, how to use that framing to select an appropriate mixture of uncertainty analyses techniques, and how to integrate the techniques into an uncertainty assessment that effectively communicates important information and insight to decision-makers. The approach is presented in this report. Practical guidance on characterizing and analyzing uncertainties about model form and quantities and on effectively communicating uncertainty analysis results is included. Examples from actual applications are presented

  11. Failure mode effect analysis and fault tree analysis as a combined methodology in risk management

    Science.gov (United States)

    Wessiani, N. A.; Yoshio, F.

    2018-04-01

    There have been many studies reported the implementation of Failure Mode Effect Analysis (FMEA) and Fault Tree Analysis (FTA) as a method in risk management. However, most of the studies usually only choose one of these two methods in their risk management methodology. On the other side, combining these two methods will reduce the drawbacks of each methods when implemented separately. This paper aims to combine the methodology of FMEA and FTA in assessing risk. A case study in the metal company will illustrate how this methodology can be implemented. In the case study, this combined methodology will assess the internal risks that occur in the production process. Further, those internal risks should be mitigated based on their level of risks.

  12. Meta-analysis: Risk of dry mouth with second generation antidepressants.

    Science.gov (United States)

    Cappetta, Kiley; Beyer, Chad; Johnson, Jessica A; Bloch, Michael H

    2018-06-08

    The goal of this meta-analysis was to quantify the risk of dry mouth associated with commonly prescribed antidepressant agents and examine the potential implications of medication class, dose, and pharmacodynamics and dose on risk of treatment-induced dry mouth. A PubMed search was conducted to identify double-blind, randomized, placebo-controlled trials examining the efficacy and tolerability of second generation antidepressant medications for adults with depressive disorders, anxiety disorders, and OCD. A random-effects meta-analysis was used to quantify the pooled risk ratio of treatment-emergent dry mouth with second generation antidepressants compared to placebo. Stratified subgroup analysis and meta-regression was utilized to further examine the effects antidepressant agent, class, dosage, indication, and receptor affinity profile on the measured risk of dry mouth. 99 trials involving 20,868 adults. SNRIs (Relative Risk (RR)=2.24, 95% Confidence Interval (CI): 1.95-2.58, z=11.2, pz=5.8, pz=10.32, pz=5.85, pz=3.26, p=0.001) and Alpha-2 (PE=0.49, 95% CI: 0.22-0.75, z=3.64, pz=2.10, p<0.05) was significantly associated with increased risk of dry mouth. The current meta-analysis suggests that SSRIs, SNRIs, and atypical antidepressants are all associated with varying degrees of increased risk of dry mouth. SNRIs were associated with a significantly greater risk of dry mouth compared to SSRIs. Copyright © 2017 Elsevier Inc. All rights reserved.

  13. RISK ANALYSIS IN MILK PROCESSING

    Directory of Open Access Journals (Sweden)

    I. PIRVUTOIU

    2008-05-01

    Full Text Available This paper aimed to evaluate Risk bankruptcy using “Score Method” based on Canon and Holder’s Model. The data were collected from the Balance Sheet and Profit and Loss Account for the period 2005-2007, recorded by a Meat processing Plant (Rador Commercial Company .The study has put in evidence the financial situation of the company,the level of the main financial ratios fundamenting the calculation of Z score function value in the three years The low values of Z score function recorded every year reflects that the company is still facing backruptcy. However , the worst situation was recorded in the years 2005 and 2006, when baknruptcy risk was ranging between 70 – 80 % . In the year 2007, the risk bankruptcy was lower, ranging between 50-70 % , as Z function recorded a value lower than 4 .For Meat processing companies such an analysis is compulsory at present as long as business environment is very risky in our country.

  14. Quantitative risk analysis preoperational of gas pipeline

    Energy Technology Data Exchange (ETDEWEB)

    Manfredi, Carlos; Bispo, Gustavo G.; Esteves, Alvaro [Gie S.A., Buenos Aires (Argentina)

    2009-07-01

    The purpose of this analysis is to predict how it can be affected the individual risk and the public's general security due to the operation of a gas pipeline. In case that the single or social risks are considered intolerable, compared with the international standards, to be recommended measures of mitigation of the risk associated to the operation until levels that can be considered compatible with the best practices in the industry. The quantitative risk analysis calculates the probability of occurrence of an event based on the frequency of occurrence of the same one and it requires a complex mathematical treatment. The present work has as objective to develop a calculation methodology based on the previously mentioned publication. This calculation methodology is centered in defining the frequencies of occurrence of events, according to representative database of each case in study. Besides, it settles down the consequences particularly according to the considerations of each area and the different possibilities of interferences with the gas pipeline in study. For each one of the interferences a typical curve of ignition probabilities is developed in function from the distance to the pipe. (author)

  15. Risk and Interdependencies in Critical Infrastructures A Guideline for Analysis

    CERN Document Server

    Utne, Ingrid; Vatn, Jørn

    2012-01-01

    Today’s society is completely dependent on critical networks such as  water supply, sewage, electricity, ICT and transportation. Risk and vulnerability analyses are needed to grasp the impact of threats and hazards. However, these become quite complex as there are strong interdependencies both within and between infrastructure systems. Risk and Interdependencies in Critical Infrastructures: A  guideline for analysis provides methods for analyzing risks and interdependencies of critical infrastructures.  A number of analysis approaches are described and are adapted to each of these infrastructures. Various approaches are also revised, and all are supported by several examples and illustrations. Particular emphasis is given to the analysis of various interdependencies that often exist between the infrastructures.  Risk and Interdependencies in Critical Infrastructures: A  guideline for analysis provides a good tool to identify the hazards that are threatening your infrastructures, and will enhance the un...

  16. WE-B-BRC-02: Risk Analysis and Incident Learning

    International Nuclear Information System (INIS)

    Fraass, B.

    2016-01-01

    Prospective quality management techniques, long used by engineering and industry, have become a growing aspect of efforts to improve quality management and safety in healthcare. These techniques are of particular interest to medical physics as scope and complexity of clinical practice continue to grow, thus making the prescriptive methods we have used harder to apply and potentially less effective for our interconnected and highly complex healthcare enterprise, especially in imaging and radiation oncology. An essential part of most prospective methods is the need to assess the various risks associated with problems, failures, errors, and design flaws in our systems. We therefore begin with an overview of risk assessment methodologies used in healthcare and industry and discuss their strengths and weaknesses. The rationale for use of process mapping, failure modes and effects analysis (FMEA) and fault tree analysis (FTA) by TG-100 will be described, as well as suggestions for the way forward. This is followed by discussion of radiation oncology specific risk assessment strategies and issues, including the TG-100 effort to evaluate IMRT and other ways to think about risk in the context of radiotherapy. Incident learning systems, local as well as the ASTRO/AAPM ROILS system, can also be useful in the risk assessment process. Finally, risk in the context of medical imaging will be discussed. Radiation (and other) safety considerations, as well as lack of quality and certainty all contribute to the potential risks associated with suboptimal imaging. The goal of this session is to summarize a wide variety of risk analysis methods and issues to give the medical physicist access to tools which can better define risks (and their importance) which we work to mitigate with both prescriptive and prospective risk-based quality management methods. Learning Objectives: Description of risk assessment methodologies used in healthcare and industry Discussion of radiation oncology

  17. WE-B-BRC-02: Risk Analysis and Incident Learning

    Energy Technology Data Exchange (ETDEWEB)

    Fraass, B. [Cedars Sinai Medical Center (United States)

    2016-06-15

    Prospective quality management techniques, long used by engineering and industry, have become a growing aspect of efforts to improve quality management and safety in healthcare. These techniques are of particular interest to medical physics as scope and complexity of clinical practice continue to grow, thus making the prescriptive methods we have used harder to apply and potentially less effective for our interconnected and highly complex healthcare enterprise, especially in imaging and radiation oncology. An essential part of most prospective methods is the need to assess the various risks associated with problems, failures, errors, and design flaws in our systems. We therefore begin with an overview of risk assessment methodologies used in healthcare and industry and discuss their strengths and weaknesses. The rationale for use of process mapping, failure modes and effects analysis (FMEA) and fault tree analysis (FTA) by TG-100 will be described, as well as suggestions for the way forward. This is followed by discussion of radiation oncology specific risk assessment strategies and issues, including the TG-100 effort to evaluate IMRT and other ways to think about risk in the context of radiotherapy. Incident learning systems, local as well as the ASTRO/AAPM ROILS system, can also be useful in the risk assessment process. Finally, risk in the context of medical imaging will be discussed. Radiation (and other) safety considerations, as well as lack of quality and certainty all contribute to the potential risks associated with suboptimal imaging. The goal of this session is to summarize a wide variety of risk analysis methods and issues to give the medical physicist access to tools which can better define risks (and their importance) which we work to mitigate with both prescriptive and prospective risk-based quality management methods. Learning Objectives: Description of risk assessment methodologies used in healthcare and industry Discussion of radiation oncology

  18. Analysis of interactions among barriers in project risk management

    Science.gov (United States)

    Dandage, Rahul V.; Mantha, Shankar S.; Rane, Santosh B.; Bhoola, Vanita

    2018-03-01

    In the context of the scope, time, cost, and quality constraints, failure is not uncommon in project management. While small projects have 70% chances of success, large projects virtually have no chance of meeting the quadruple constraints. While there is no dearth of research on project risk management, the manifestation of barriers to project risk management is a less dwelt topic. The success of project management is oftentimes based on the understanding of barriers to effective risk management, application of appropriate risk management methodology, proactive leadership to avoid barriers, workers' attitude, adequate resources, organizational culture, and involvement of top management. This paper represents various risk categories and barriers to risk management in domestic and international projects through literature survey and feedback from project professionals. After analysing the various modelling methods used in project risk management literature, interpretive structural modelling (ISM) and MICMAC analysis have been used to analyse interactions among the barriers and prioritize them. The analysis indicates that lack of top management support, lack of formal training, and lack of addressing cultural differences are the high priority barriers, among many others.

  19. Risk analysis for earth dam overtopping

    Directory of Open Access Journals (Sweden)

    Mo Chongxun

    2008-06-01

    Full Text Available In this paper, a model of overtopping risk under the joint effects of floods and wind waves, which is based on risk analysis theory and takes into account the uncertainties of floods, wind waves, reservoir capacity and discharge capacity of the spillway, is proposed and applied to the Chengbihe Reservoir in Baise City in Guangxi Zhuang Autonomous Region. The simulated results indicate that the flood control limiting level can be raised by 0.40 m under the condition that the reservoir overtopping risk is controlled within a mean variance of 5×10−6. As a result, the reservoir storage will increase to 16 million m3 and electrical energy generation and other functions of the reservoir will also increase greatly.

  20. Essays on Systemic Risk : An analysis from multiple perspectives

    NARCIS (Netherlands)

    S. Muns (Sander)

    2016-01-01

    markdownabstractThis thesis is about systemic risk in the financial sector. It considers several aspects of systemic risk. It is a building block for an analysis of the impact of systemic risk on the real economy. It appears that stocks in the financial industry show a strong interdependence

  1. Quantitative risk analysis as a basis for emergency planning

    Energy Technology Data Exchange (ETDEWEB)

    Yogui, Regiane Tiemi Teruya [Bureau Veritas do Brasil, Rio de Janeiro, RJ (Brazil); Macedo, Eduardo Soares de [Instituto de Pesquisas Tecnologicas (IPT), Sao Paulo, SP (Brazil)

    2009-07-01

    Several environmental accidents happened in Brazil and in the world during the 70's and 80's. This strongly motivated the preparation for emergencies in the chemical and petrochemical industries. Environmental accidents affect the environment and the communities that are neighbor to the industrial facilities. The present study aims at subsidizing and providing orientation to develop Emergency Planning from the data obtained on Quantitative Risk Analysis, elaborated according to the Technical Standard P4.261/03 from CETESB (Sao Paulo Environmental Agency). It was observed, during the development of the research, that the data generated on these studies need a complementation and a deeper analysis, so that it is possible to use them on the Emergency Plans. The main issues that were analyzed and discussed on this study were the reevaluation of hazard identification for the emergency plans, the consequences and vulnerability analysis for the response planning, the risk communication, and the preparation to respond to the emergencies of the communities exposed to manageable risks. As a result, the study intends to improve the interpretation and use of the data deriving from the Quantitative Risk Analysis to develop the emergency plans. (author)

  2. Risk analysis of radioactive waste management systems in Germany

    International Nuclear Information System (INIS)

    Wingender, H.J.

    1978-01-01

    Within the scope of a system study, ''Radioactive wastes in the Federal Republic of Germany,'' performed from 1974 through 1976, the questions of risk assessment were investigated. A risk analysis of a high-level waste (HLW) management system was performed. The results of the HLW tank storage are that the risk expectation value is 700 nJ/kg x RBE (7 x 10 -5 rem) per year for atmospheric release. The discussion of the main contributing accidents shows the possibility of reducing the risk by a technical means. A qualitative comparison on the release basis with the results of the WASH-1400 report shows significant differences that can be explained by the different methodologies applied. The risk analysis activities have led to a comprehensive risk assessment project, which was recently started. The projected includes research and development tasks concerning nuclide migration and transport to the ecosphere, nuclide mobilization by various mechanisms, methodology problems, data collection, computer code development, as well as risk analyses of waste management facilities. It is intended to round off the project with risk analyses of spent fuel element transport, storage, and reprocessing

  3. Sliding mode based trajectory linearization control for hypersonic reentry vehicle via extended disturbance observer.

    Science.gov (United States)

    Xingling, Shao; Honglun, Wang

    2014-11-01

    This paper proposes a novel hybrid control framework by combing observer-based sliding mode control (SMC) with trajectory linearization control (TLC) for hypersonic reentry vehicle (HRV) attitude tracking problem. First, fewer control consumption is achieved using nonlinear tracking differentiator (TD) in the attitude loop. Second, a novel SMC that employs extended disturbance observer (EDO) to counteract the effect of uncertainties using a new sliding surface which includes the estimation error is integrated to address the tracking error stabilization issues in the attitude and angular rate loop, respectively. In addition, new results associated with EDO are examined in terms of dynamic response and noise-tolerant performance, as well as estimation accuracy. The key feature of the proposed compound control approach is that chattering free tracking performance with high accuracy can be ensured for HRV in the presence of multiple uncertainties under control constraints. Based on finite time convergence stability theory, the stability of the resulting closed-loop system is well established. Also, comparisons and extensive simulation results are presented to demonstrate the effectiveness of the control strategy. Copyright © 2014 ISA. Published by Elsevier Ltd. All rights reserved.

  4. Risk analysis tools for force protection and infrastructure/asset protection

    International Nuclear Information System (INIS)

    Jaeger, C.D.; Duggan, R.A.; Paulus, W.K.

    1998-01-01

    The Security Systems and Technology Center at Sandia National Laboratories has for many years been involved in the development and use of vulnerability assessment and risk analysis tools. In particular, two of these tools, ASSESS and JTS, have been used extensively for Department of Energy facilities. Increasingly, Sandia has been called upon to evaluate critical assets and infrastructures, support DoD force protection activities and assist in the protection of facilities from terrorist attacks using weapons of mass destruction. Sandia is involved in many different activities related to security and force protection and is expanding its capabilities by developing new risk analysis tools to support a variety of users. One tool, in the very early stages of development, is EnSURE, Engineered Surety Using the Risk Equation. EnSURE addresses all of the risk equation and integrates the many components into a single, tool-supported process to help determine the most cost-effective ways to reduce risk. This paper will briefly discuss some of these risk analysis tools within the EnSURE framework

  5. Operational Risk Management A Practical Approach to Intelligent Data Analysis

    CERN Document Server

    Kenett, Ron

    2010-01-01

    The book will introduce modern Operational Risk (OpR) Management and illustrates the various sources of OpR assessment and OpR mitigation. This book discusses how various data sources can be integrated and analyzed and how OpR is synergetic to other risk management activities such as Financial Risk Management and Internationalization. The topics will include state of the art technology such as semantic analysis, ontology engineering, data mining and statistical analysis.

  6. Intentional risk management through complex networks analysis

    CERN Document Server

    Chapela, Victor; Moral, Santiago; Romance, Miguel

    2015-01-01

    This book combines game theory and complex networks to examine intentional technological risk through modeling. As information security risks are in constant evolution,  the methodologies and tools to manage them must evolve to an ever-changing environment. A formal global methodology is explained  in this book, which is able to analyze risks in cyber security based on complex network models and ideas extracted from the Nash equilibrium. A risk management methodology for IT critical infrastructures is introduced which provides guidance and analysis on decision making models and real situations. This model manages the risk of succumbing to a digital attack and assesses an attack from the following three variables: income obtained, expense needed to carry out an attack, and the potential consequences for an attack. Graduate students and researchers interested in cyber security, complex network applications and intentional risk will find this book useful as it is filled with a number of models, methodologies a...

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

    Science.gov (United States)

    Meloy, Anthony F.

    2006-09-01

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

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

    International Nuclear Information System (INIS)

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

    2004-01-01

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

  9. Analysis of risk assessment methods for goods trucking

    Directory of Open Access Journals (Sweden)

    Yunyazova A.O.

    2018-04-01

    Full Text Available the article considers models of risk assessment that can be applied to cargo transportation, for forecasting possible damage in the form of financial and material costs in order to reduce the percentage of probability of their occurrence. The analysis of risk by the method «Criterion. Event. Rule" is represented. This method is based on the collection of information by various methods, assigning an assessment to the identified risks, ranking and formulating a report on the analysis. It can be carried out as a fully manual mechanical method of information collecting and performing calculations or can be brought to an automated level from data collection to the delivery of finished results (but in this case some nuances that could significantly influence the outcome of the analysis can be ignored. The expert method is of particular importance, since it relies directly on human experience. In this case, a special role is played by the human factor. The collection of information and the assigned assessments to risk groups depend on the extent to which experts agree on this issue. The smaller the fluctuations in the values ​​of the estimates of the experts, the more accurate and optimal the results will be.

  10. Cable Hot Shorts and Circuit Analysis in Fire Risk Assessment

    International Nuclear Information System (INIS)

    LaChance, Jeffrey; Nowlen, Steven P.; Wyant, Frank

    1999-01-01

    Under existing methods of probabilistic risk assessment (PRA), the analysis of fire-induced circuit faults has typically been conducted on a simplistic basis. In particular, those hot-short methodologies that have been applied remain controversial in regards to the scope of the assessments, the underlying methods, and the assumptions employed. To address weaknesses in fire PRA methodologies, the USNRC has initiated a fire risk analysis research program that includes a task for improving the tools for performing circuit analysis. The objective of this task is to obtain a better understanding of the mechanisms linking fire-induced cable damage to potentially risk-significant failure modes of power, control, and instrumentation cables. This paper discusses the current status of the circuit analysis task

  11. Impact Analysis for Risks in Informatics Systems

    OpenAIRE

    Baicu, Floarea; Baches, Maria Alexandra

    2013-01-01

    In this paper are presented methods of impact analysis on informatics system security accidents, qualitative and quantitative methods, starting with risk and informational system security definitions. It is presented the relationship between the risks of exploiting vulnerabilities of security system, security level of these informatics systems, probability of exploiting the weak points subject to financial losses of a company, respectively impact of a security accident on the company. Herewit...

  12. Risk D and D Rapid Prototype: Scenario Documentation and Analysis Tool

    International Nuclear Information System (INIS)

    Unwin, Stephen D.; Seiple, Timothy E.

    2009-01-01

    Report describes process and methodology associated with a rapid prototype tool for integrating project risk analysis and health and safety risk analysis for decontamination and decommissioning projects. The objective of the Decontamination and Decommissioning (D and D) Risk Management Evaluation and Work Sequencing Standardization Project under DOE EM-23 is to recommend or develop practical risk-management tools for decommissioning of nuclear facilities. PNNL has responsibility under this project for recommending or developing computer-based tools that facilitate the evaluation of risks in order to optimize the sequencing of D and D work. PNNL's approach is to adapt, augment, and integrate existing resources rather than to develop a new suite of tools. Methods for the evaluation of H and S risks associated with work in potentially hazardous environments are well-established. Several approaches exist which, collectively, are referred to as process hazard analysis (PHA). A PHA generally involves the systematic identification of accidents, exposures, and other adverse events associated with a given process or work flow. This identification process is usually achieved in a brainstorming environment or by other means of eliciting informed opinion. The likelihoods of adverse events (scenarios) and their associated consequence severities are estimated against pre-defined scales, based on which risk indices are then calculated. A similar process is encoded in various project risk software products that facilitate the quantification of schedule and cost risks associated with adverse scenarios. However, risk models do not generally capture both project risk and H and S risk. The intent of the project reported here is to produce a tool that facilitates the elicitation, characterization, and documentation of both project risk and H and S risk based on defined sequences of D and D activities. By considering alternative D and D sequences, comparison of the predicted risks can

  13. HCN Production via Impact Ejecta Reentry During the Late Heavy Bombardment

    Science.gov (United States)

    Parkos, Devon; Pikus, Aaron; Alexeenko, Alina; Melosh, H. Jay

    2018-04-01

    Major impact events have shaped the Earth as we know it. The Late Heavy Bombardment is of particular interest because it immediately precedes the first evidence of life. The reentry of impact ejecta creates numerous chemical by-products, including biotic precursors such as HCN. This work examines the production of HCN during the Late Heavy Bombardment in more detail. We stochastically simulate the range of impacts on the early Earth and use models developed from existing studies to predict the corresponding ejecta properties. Using multiphase flow methods and finite-rate equilibrium chemistry, we then find the HCN production due to the resulting atmospheric heating. We use Direct Simulation Monte Carlo to develop a correction factor to account for increased yields due to thermochemical nonequilibrium. We then model 1-D atmospheric turbulent diffusion to find the time accurate transport of HCN to lower altitudes and ultimately surface water. Existing works estimate the necessary HCN molarity threshold to promote polymerization that is 0.01 M. For a mixing depth of 100 m, we find that the Late Heavy Bombardment will produce at least one impact event above this threshold with probability 24.1% for an oxidized atmosphere and 56.3% for a partially reduced atmosphere. For a mixing depth of 10 m, the probability is 79.5% for an oxidized atmosphere and 96.9% for a partially reduced atmosphere. Therefore, Late Heavy Bombardment impact ejecta is likely an HCN source sufficient for polymerization in shallow bodies of water, particularly if the atmosphere were in a partially reduced state.

  14. A risk-informed perspective on deterministic safety analysis of nuclear power plants

    International Nuclear Information System (INIS)

    Wan, P.T.

    2009-01-01

    In this work, the deterministic safety analysis (DSA) approach to nuclear safety is examined from a risk-informed perspective. One objective of safety analysis of a nuclear power plant is to demonstrate via analysis that the risks to the public from events or accidents that are within the design basis of the power plant are within acceptable levels with a high degree of assurance. This nuclear safety analysis objective can be translated into two requirements on the risk estimates of design basis events or accidents: the nominal risk estimate to the public must be shown to be within acceptable levels, and the uncertainty in the risk estimates must be shown to be small on an absolute or relative basis. The DSA approach combined with the defense-in-depth (DID) principle is a simplified safety analysis approach that attempts to achieve the above safety analysis objective in the face of potentially large uncertainties in the risk estimates of a nuclear power plant by treating the various uncertainty contributors using a stylized conservative binary (yes-no) approach, and applying multiple overlapping physical barriers and defense levels to protect against the release of radioactivity from the reactor. It is shown that by focusing on the consequence aspect of risk, the previous two nuclear safety analysis requirements on risk can be satisfied with the DSA-DID approach to nuclear safety. It is also shown the use of multiple overlapping physical barriers and defense levels in the traditional DSA-DID approach to nuclear safety is risk-informed in the sense that it provides a consistently high level of confidence in the validity of the safety analysis results for various design basis events or accidents with a wide range of frequency of occurrence. It is hoped that by providing a linkage between the consequence analysis approach in DSA with a risk-informed perspective, greater understanding of the limitation and capability of the DSA approach is obtained. (author)

  15. Risk factor analysis of equine strongyle resistance to anthelmintics

    Directory of Open Access Journals (Sweden)

    G. Sallé

    2017-12-01

    Full Text Available Intestinal strongyles are the most problematic endoparasites of equids as a result of their wide distribution and the spread of resistant isolates throughout the world. While abundant literature can be found on the extent of anthelmintic resistance across continents, empirical knowledge about associated risk factors is missing. This study brought together results from anthelmintic efficacy testing and risk factor analysis to provide evidence-based guidelines in the field. It involved 688 horses from 39 French horse farms and riding schools to both estimate Faecal Egg Count Reduction (FECR after anthelmintic treatment and to interview farm and riding school managers about their practices. Risk factors associated with reduced anthelmintic efficacy in equine strongyles were estimated across drugs using a marginal modelling approach. Results demonstrated ivermectin efficacy (96.3% ± 14.5% FECR, the inefficacy of fenbendazole (42.8% ± 33.4% FECR and an intermediate profile for pyrantel (90.3% ± 19.6% FECR. Risk factor analysis provided support to advocate for FEC-based treatment regimens combined with individual anthelmintic dosage and the enforcement of tighter biosecurity around horse introduction. The combination of these measures resulted in a decreased risk of drug resistance (relative risk of 0.57, p = 0.02. Premises falling under this typology also relied more on their veterinarians suggesting practitionners play an important role in the sustainability of anthelmintic usage. Similarly, drug resistance risk was halved in premises with frequent pasture rotation and with stocking rate below five horses/ha (relative risk of 0.53, p < 0.01. This is the first empirical risk factor analysis for anthelmintic resistance in equids. Our findings should guide the implementation of more sustained strongyle management in the field. Keywords: Horse, Nematode, Anthelmintic resistance, Strongyle, Cyathostomin

  16. Stress Analysis in Managing the Region’s Budget Risks

    Directory of Open Access Journals (Sweden)

    Natalya Pavlovna Pazdnikova

    2014-09-01

    Full Text Available The article addresses the implementation of budget risk management methods into the practices of governmental authorities. Drawing on the example of a particular region the article aims to demonstrate the possible methods of budget risk management. The authors refine the existing approaches to the notion of risk in its relation to budget system by introducing the notion of “budget risk.” Here the focus is the risk of default of budget spending in full which causes underfunding of territories and decrease in quality of life in the region. The authors have particularized the classification of budget risks and grouped together the criteria and factors which significantly influence the assessment and choice of method to manage budget risks. They hypothesize that budget risk is a financial risk. Therefore, the methods of financial risks management can be applied to budget risks management. The authors suggest a methodological approach to risk assessment based on correlation and regression analysis of program financing. The application of Kendall rank correlation coefficient allowed to assess the efficiency of budget spending on the implementation of state programs in Perm Krai. Two clusters — “Nature management and infrastructure” and “Public security” — turned out to be in the zone of high budget risk. The method of stress analysis, which consists in calculating Value at Risk (VaR, was applied to budget risks that in terms of probability are classified as critical. In order to assess risk as probability rate, the amount of Perm Krai deficit budget was calculated as induced variable from budget revenues and spending. The results demonstrate that contemporary management of public resources in the regions calls for the implementation of new management tools of higher quality and budget risk management is one of them.

  17. Explaining HIV Risk Multiplexity: A Social Network Analysis.

    Science.gov (United States)

    Felsher, Marisa; Koku, Emmanuel

    2018-04-21

    Risk multiplexity (i.e., overlap in drug-use, needle exchange and sexual relations) is a known risk factor for HIV. However, little is known about predictors of multiplexity. This study uses egocentric data from the Colorado Springs study to examine how individual, behavioral and social network factors influence engagement in multiplex risk behavior. Analyses revealed that compared to Whites, Hispanics were significantly more likely to engage in risk multiplexity and Blacks less so. Respondents who were similar to each other (e.g., in terms of race) had significantly higher odds of being in risk multiplex relationships, and respondents' risk perceptions and network size were significantly associated with engaging in multiplex risk behaviors. Findings from interaction analysis showed the effect of knowing someone with HIV on the odds of multiplexity depends partly on whether respondents' know their HIV status. Findings suggest that demographics, HIV behaviors and network factors impact engagement in multiplex risk behaviors, highlighting the need for multi-level interventions aimed at reducing HIV risk behavior.

  18. Dynamic risk analysis using bow-tie approach

    International Nuclear Information System (INIS)

    Khakzad, Nima; Khan, Faisal; Amyotte, Paul

    2012-01-01

    Accident probability estimation is a common and central step to all quantitative risk assessment methods. Among many techniques available, bow-tie model (BT) is very popular because it represent the accident scenario altogether including causes and consequences. However, it suffers a static structure limiting its application in real-time monitoring and probability updating which are key factors in dynamic risk analysis. The present work is focused on using BT approach in a dynamic environment in which the occurrence probability of accident consequences changes. In this method, on one hand, failure probability of primary events of BT, leading to the top event, are developed using physical reliability models, and constantly revised as physical parameters (e.g., pressure, velocity, dimension, etc) change. And, on the other hand, the failure probability of safety barriers of the BT are periodically updated using Bayes’ theorem as new information becomes available over time. Finally, the resulting, updated BT is used to estimate the posterior probability of the consequences which in turn results in an updated risk profile. - Highlights: ► A methodology is proposed to make bow-tie method adapted for dynamic risk analysis. ► Physical reliability models are used to revise the top event. ► Bayes’ theorem is used to update the probability of safety barriers. ► The number of accidents in sequential time intervals is used to form likelihood function. ► The risk profile is updated for varying physical parameters and for different times.

  19. Project Portfolio Risk Identification and Analysis, Considering Project Risk Interactions and Using Bayesian Networks

    Directory of Open Access Journals (Sweden)

    Foroogh Ghasemi

    2018-05-01

    Full Text Available An organization’s strategic objectives are accomplished through portfolios. However, the materialization of portfolio risks may affect a portfolio’s sustainable success and the achievement of those objectives. Moreover, project interdependencies and cause–effect relationships between risks create complexity for portfolio risk analysis. This paper presents a model using Bayesian network (BN methodology for modeling and analyzing portfolio risks. To develop this model, first, portfolio-level risks and risks caused by project interdependencies are identified. Then, based on their cause–effect relationships all portfolio risks are organized in a BN. Conditional probability distributions for this network are specified and the Bayesian networks method is used to estimate the probability of portfolio risk. This model was applied to a portfolio of a construction company located in Iran and proved effective in analyzing portfolio risk probability. Furthermore, the model provided valuable information for selecting a portfolio’s projects and making strategic decisions.

  20. The prostate cancer risk stratification (ProCaRS) project: Recursive partitioning risk stratification analysis

    International Nuclear Information System (INIS)

    Rodrigues, George; Lukka, Himu; Warde, Padraig; Brundage, Michael; Souhami, Luis; Crook, Juanita; Cury, Fabio; Catton, Charles; Mok, Gary; Martin, Andre-Guy; Vigneault, Eric; Morris, Jim; Warner, Andrew; Gonzalez Maldonado, Sandra; Pickles, Tom

    2013-01-01

    Background: The Genitourinary Radiation Oncologists of Canada (GUROC) published a three-group risk stratification (RS) system to assist prostate cancer decision-making in 2001. The objective of this project is to use the ProCaRS database to statistically model the predictive accuracy and clinical utility of a proposed new multi-group RS schema. Methods: The RS analyses utilized the ProCaRS database that consists of 7974 patients from four Canadian institutions. Recursive partitioning analysis (RPA) was utilized to explore the sub-stratification of groups defined by the existing three-group GUROC scheme. 10-fold cross-validated C-indices and the Net Reclassification Index were both used to assess multivariable models and compare the predictive accuracy of existing and proposed RS systems, respectively. Results: The recursive partitioning analysis has suggested that the existing GUROC classification system could be altered to accommodate as many as six separate and statistical unique groups based on differences in BFFS (C-index 0.67 and AUC 0.70). GUROC low-risk patients would be divided into new favorable-low and low-risk groups based on PSA ⩽6 and PSA >6. GUROC intermediate-risk patients can be subclassified into low-intermediate and high-intermediate groups. GUROC high-intermediate-risk is defined as existing GUROC intermediate-risk with PSA >=10 AND either T2b/c disease or T1T2a disease with Gleason 7. GUROC high-risk patients would be subclassified into an additional extreme-risk group (GUROC high-risk AND (positive cores ⩾87.5% OR PSA >30). Conclusions: Proposed RS subcategories have been identified by a RPA of the ProCaRS database

  1. THE ANALYSIS OF RISK MANAGEMENT PROCESS WITHIN MANAGEMENT

    Directory of Open Access Journals (Sweden)

    ROMANESCU MARCEL LAURENTIU

    2016-10-01

    Full Text Available This article highlights the risk analysis within management, focusing on how a company could practicaly integrate the risks management in the existing leading process. Subsequently, it is exemplified the way of manage risk effectively, which gives numerous advantages to all firms, including improving their decision-making process. All these lead to the conclusion that the degree of risk specific to companies is very high, but if managers make the best decisions then it can diminish it and all business activitiy and its income are not influenced by factors that could disturb in a negative way .

  2. Use-related risk analysis for medical devices based on improved FMEA.

    Science.gov (United States)

    Liu, Long; Shuai, Ma; Wang, Zhu; Li, Ping

    2012-01-01

    In order to effectively analyze and control use-related risk of medical devices, quantitative methodologies must be applied. Failure Mode and Effects Analysis (FMEA) is a proactive technique for error detection and risk reduction. In this article, an improved FMEA based on Fuzzy Mathematics and Grey Relational Theory is developed to better carry out user-related risk analysis for medical devices. As an example, the analysis process using this improved FMEA method for a certain medical device (C-arm X-ray machine) is described.

  3. Synthesis of Enterprise and Value-Based Methods for Multiattribute Risk Analysis

    International Nuclear Information System (INIS)

    Kenley, C. Robert; Collins, John W.; Beck, John M.; Heydt, Harold J.; Garcia, Chad B.

    2001-01-01

    This paper describes a method for performing multiattribute decision analysis to prioritize ap-proaches to handling risks during the development and operation of complex socio-technical systems. The method combines risk categorization based on enterprise views, risk prioritization of the categories based on the Analytic Hierarchy Process (AHP), and more standard probability-consequence ratings schemes. We also apply value-based testing me-thods used in software development to prioritize risk-handling approaches. We describe a tool that synthesizes the methods and performs a multiattribute analysis of the technical and pro-grammatic risks on the Next Generation Nuclear Plant (NGNP) enterprise.

  4. 75 FR 75619 - Waiver of Acceptable Mission Risk Restriction for Reentry and a Reentry Vehicle

    Science.gov (United States)

    2010-12-06

    ... the International Space Station. 10. Dragon has redundant drogue parachutes and dual redundant main... waiver ``in a timely fashion.'' As such, the FAA has found that SpaceX had good cause for submitting its...

  5. Serum Proteases Potentiate BMP-Induced Cell Cycle Re-entry of Dedifferentiating Muscle Cells during Newt Limb Regeneration.

    Science.gov (United States)

    Wagner, Ines; Wang, Heng; Weissert, Philipp M; Straube, Werner L; Shevchenko, Anna; Gentzel, Marc; Brito, Goncalo; Tazaki, Akira; Oliveira, Catarina; Sugiura, Takuji; Shevchenko, Andrej; Simon, András; Drechsel, David N; Tanaka, Elly M

    2017-03-27

    Limb amputation in the newt induces myofibers to dedifferentiate and re-enter the cell cycle to generate proliferative myogenic precursors in the regeneration blastema. Here we show that bone morphogenetic proteins (BMPs) and mature BMPs that have been further cleaved by serum proteases induce cell cycle entry by dedifferentiating newt muscle cells. Protease-activated BMP4/7 heterodimers that are present in serum strongly induced myotube cell cycle re-entry with protease cleavage yielding a 30-fold potency increase of BMP4/7 compared with canonical BMP4/7. Inhibition of BMP signaling via muscle-specific dominant-negative receptor expression reduced cell cycle entry in vitro and in vivo. In vivo inhibition of serine protease activity depressed cell cycle re-entry, which in turn was rescued by cleaved-mimic BMP. This work identifies a mechanism of BMP activation that generates blastema cells from differentiated muscle. Copyright © 2017 Elsevier Inc. All rights reserved.

  6. Risk analysis

    International Nuclear Information System (INIS)

    Correa Lizarazu, X.

    2013-01-01

    The power point presentation Colombia risk evaluation experiences, sanitarian regulations evolution, chemical dangers food, biological dangers food, codex alimentarius, trade, industrial effects, dangers identification, data collection and risk profile

  7. The approach to risk analysis in three industries

    International Nuclear Information System (INIS)

    Garrick, B.J.

    1991-01-01

    It is the purpose of this paper to review how risk and safety analysis is performed in the three major industries of nuclear power, space flight, and chemical and petroleum processes. The underlying reason for such a review is the belief that efficiencies and safety enhancements may result from a greater exchange of risk assessment technology between these industries. The thrust of this discussion related to the engineered systems involved in the three industries. The industries are very different. The chemical industry epitomizes the highly competitive private sector and its bottom-line emphasis; the nuclear power industry is unique by the degree to which it is regulated; and the space industry is essentially a government business just beginning to have commercial implications. Institutional differences are extreme; however, from a societal needs, and their safety implications have a far reaching impact on public opinion and support. In reviewing the risk and safety analysis activities, particular attention is given to the use of such quantitative approaches as probabilistic risk assessment (PRA) as it has evolved in the nuclear power industry

  8. Risk analysis and priority setting for environmental policy

    International Nuclear Information System (INIS)

    Travis, C.C.

    1991-01-01

    There is a growing realization that the demand for funding to correct our nation's environmental problems will soon outstrip available resources. In the hazardous waste area alone, the estimated cost of remediating Superfund sites ranges from $32 billion to $80 billion. Numerous other areas of competing for these same financial resources. These include ozone depletion, global warming, the protection of endangered species and wetlands, toxic air pollution, carcinogenic pesticides, and urban smog. In response to this imbalance in the supply and demand for national funds, several political constituencies are calling for the use of risk assessment as a tool in the prioritization of research and budget needs. Comparative risk analysis offers a logical framework in which to organize information about complex environmental problems. Risk analysis allows policy analysts to make resource allocation decisions on the basis of scientific judgement rather than political expediency

  9. Body mass index and risk of BPH: a meta-analysis.

    Science.gov (United States)

    Wang, S; Mao, Q; Lin, Y; Wu, J; Wang, X; Zheng, X; Xie, L

    2012-09-01

    Epidemiological studies have reported conflicting results relating obesity to BPH. A meta-analysis of cohort and case-control studies was conducted to pool the risk estimates of the association between obesity and BPH. Eligible studies were retrieved by both computer searches and review of references. We analyzed abstracted data with random effects models to obtain the summary risk estimates. Dose-response meta-analysis was performed for studies reporting categorical risk estimates for a series of exposure levels. A total of 19 studies met the inclusion criteria of the meta-analysis. Positive association with body mass index (BMI) was observed in BPH and lower urinary tract symptoms (LUTS) combined group (odds ratio=1.27, 95% confidence intervals 1.05-1.53). In subgroup analysis, BMI exhibited a positive dose-response relationship with BPH/LUTS in population-based case-control studies and a marginal positive association was observed between risk of BPH and increased BMI. However, no association between BPH/LUTS and BMI was observed in other subgroups stratified by study design, geographical region or primary outcome. The overall current literatures suggested that BMI was associated with increased risk of BPH. Further efforts should be made to confirm these findings and clarify the underlying biological mechanisms.

  10. Adversarial risk analysis with incomplete information: a level-k approach.

    Science.gov (United States)

    Rothschild, Casey; McLay, Laura; Guikema, Seth

    2012-07-01

    This article proposes, develops, and illustrates the application of level-k game theory to adversarial risk analysis. Level-k reasoning, which assumes that players play strategically but have bounded rationality, is useful for operationalizing a Bayesian approach to adversarial risk analysis. It can be applied in a broad class of settings, including settings with asynchronous play and partial but incomplete revelation of early moves. Its computational and elicitation requirements are modest. We illustrate the approach with an application to a simple defend-attack model in which the defender's countermeasures are revealed with a probability less than one to the attacker before he decides on how or whether to attack. © 2011 Society for Risk Analysis.

  11. Structural reliability analysis applied to pipeline risk analysis

    Energy Technology Data Exchange (ETDEWEB)

    Gardiner, M. [GL Industrial Services, Loughborough (United Kingdom); Mendes, Renato F.; Donato, Guilherme V.P. [PETROBRAS S.A., Rio de Janeiro, RJ (Brazil)

    2009-07-01

    Quantitative Risk Assessment (QRA) of pipelines requires two main components to be provided. These are models of the consequences that follow from some loss of containment incident, and models for the likelihood of such incidents occurring. This paper describes how PETROBRAS have used Structural Reliability Analysis for the second of these, to provide pipeline- and location-specific predictions of failure frequency for a number of pipeline assets. This paper presents an approach to estimating failure rates for liquid and gas pipelines, using Structural Reliability Analysis (SRA) to analyze the credible basic mechanisms of failure such as corrosion and mechanical damage. SRA is a probabilistic limit state method: for a given failure mechanism it quantifies the uncertainty in parameters to mathematical models of the load-resistance state of a structure and then evaluates the probability of load exceeding resistance. SRA can be used to benefit the pipeline risk management process by optimizing in-line inspection schedules, and as part of the design process for new construction in pipeline rights of way that already contain multiple lines. A case study is presented to show how the SRA approach has recently been used on PETROBRAS pipelines and the benefits obtained from it. (author)

  12. Dealing with phenomenological uncertainty in risk analysis

    International Nuclear Information System (INIS)

    Theofanous, T.G.

    1994-01-01

    The Risk-Oriented Accident Analysis Methodology (ROAAM) is summarized and developed further towards a formal definition. The key ideas behind the methodology and these more formal aspects are also presented and discussed

  13. Risk and safety analysis of nuclear systems

    National Research Council Canada - National Science Library

    Lee, John C; McCormick, Norman J

    2011-01-01

    .... The first half of the book covers the principles of risk analysis, the techniques used to develop and update a reliability data base, the reliability of multi-component systems, Markov methods used...

  14. Physiological responses of astronaut candidates to simulated +Gx orbital emergency re-entry.

    Science.gov (United States)

    Wu, Bin; Xue, Yueying; Wu, Ping; Gu, Zhiming; Wang, Yue; Jing, Xiaolu

    2012-08-01

    We investigated astronaut candidates' physiological and pathological responses to +Gx exposure during simulated emergency return from a running orbit to advance astronaut +Gx tolerance training and medical support in manned spaceflight. There were 13 male astronaut candidates who were exposed to a simulated high +Gx acceleration profile in a spacecraft during an emergency return lasting for 230 s. The peak value was 8.5 G. Subjective feelings and symptoms, cardiovascular and respiratory responses, and changes in urine component before, during, and after +Gx exposure were investigated. Under high +Gx exposure, 15.4% of subjects exhibited arrhythmia. Heart rate (HR) increased significantly and four different types of HR response curves were distinguished. The ratio of QT to RR interval on the electrocardiograms was significantly increased. Arterial oxygen saturation (SaO2) declined with increasing G value and then returned gradually. SaO2 reached a minimum (87.7%) at 3 G during the decline phase of the +Gx curve. Respiratory rate increased significantly with increasing G value, while the amplitude and area of the respiratory waves were significantly reduced. The overshoot appeared immediately after +Gx exposure. A few subjects suffered from slight injuries, including positive urine protein (1/13), positive urinary occult blood (1/13), and a large area of petechiae on the back (1/13). Astronaut candidates have relatively good tolerance to the +Gx profile during a simulation of spacecraft emergent ballistic re-entry. However, a few subjects exhibited adverse physiological responses and slight reversible pathological injuries.

  15. Approach for seismic risk analysis for CANDU plants in Korea

    Energy Technology Data Exchange (ETDEWEB)

    Lee, B-S; Kim, T; Kang, S-K [Korea Power Engineering Co., Seoul (Korea, Republic of); Hong, S-Y; Roh, S-R [Korea Electric Power Corp., Taejon (Korea, Republic of). Research Centre

    1996-12-31

    A seismic risk analysis for CANDU type plants has never been performed. The study presented here suggested that the approach generally applied to LWR type plants could lead to unacceptable result, if directly applied to CANDU plants. This paper presents a modified approach for the seismic risk analysis of CANDU plants. (author). 5 refs., 2 tabs., 2 figs.

  16. LANDSAFE: LANDING SITE RISK ANALYSIS SOFTWARE FRAMEWORK

    Directory of Open Access Journals (Sweden)

    R. Schmidt

    2012-08-01

    Full Text Available The European Space Agency (ESA is planning a Lunar Lander mission in the 2018 timeframe that will demonstrate precise soft landing at the polar regions of the Moon. To ensure a safe and successful landing a careful risk analysis has to be carried out. This is comprised of identifying favorable target areas and evaluating the surface conditions in these areas. Features like craters, boulders, steep slopes, rough surfaces and shadow areas have to be identified in order to assess the risk associated to a landing site in terms of a successful touchdown and subsequent surface operation of the lander. In addition, global illumination conditions at the landing site have to be simulated and analyzed. The Landing Site Risk Analysis software framework (LandSAfe is a system for the analysis, selection and certification of safe landing sites on the lunar surface. LandSAfe generates several data products including high resolution digital terrain models (DTMs, hazard maps, illumination maps, temperature maps and surface reflectance maps which assist the user in evaluating potential landing site candidates. This paper presents the LandSAfe system and describes the methods and products of the different modules. For one candidate landing site on the rim of Shackleton crater at the south pole of the Moon a high resolution DTM is showcased.

  17. Risk analysis of analytical validations by probabilistic modification of FMEA

    DEFF Research Database (Denmark)

    Barends, D.M.; Oldenhof, M.T.; Vredenbregt, M.J.

    2012-01-01

    Risk analysis is a valuable addition to validation of an analytical chemistry process, enabling not only detecting technical risks, but also risks related to human failures. Failure Mode and Effect Analysis (FMEA) can be applied, using a categorical risk scoring of the occurrence, detection...... and severity of failure modes, and calculating the Risk Priority Number (RPN) to select failure modes for correction. We propose a probabilistic modification of FMEA, replacing the categorical scoring of occurrence and detection by their estimated relative frequency and maintaining the categorical scoring...... of severity. In an example, the results of traditional FMEA of a Near Infrared (NIR) analytical procedure used for the screening of suspected counterfeited tablets are re-interpretated by this probabilistic modification of FMEA. Using this probabilistic modification of FMEA, the frequency of occurrence...

  18. A Benefit-Risk Analysis Approach to Capture Regulatory Decision-Making: Multiple Myeloma.

    Science.gov (United States)

    Raju, G K; Gurumurthi, Karthik; Domike, Reuben; Kazandjian, Dickran; Landgren, Ola; Blumenthal, Gideon M; Farrell, Ann; Pazdur, Richard; Woodcock, Janet

    2018-01-01

    Drug regulators around the world make decisions about drug approvability based on qualitative benefit-risk analysis. In this work, a quantitative benefit-risk analysis approach captures regulatory decision-making about new drugs to treat multiple myeloma (MM). MM assessments have been based on endpoints such as time to progression (TTP), progression-free survival (PFS), and objective response rate (ORR) which are different than benefit-risk analysis based on overall survival (OS). Twenty-three FDA decisions on MM drugs submitted to FDA between 2003 and 2016 were identified and analyzed. The benefits and risks were quantified relative to comparators (typically the control arm of the clinical trial) to estimate whether the median benefit-risk was positive or negative. A sensitivity analysis was demonstrated using ixazomib to explore the magnitude of uncertainty. FDA approval decision outcomes were consistent and logical using this benefit-risk framework. © 2017 American Society for Clinical Pharmacology and Therapeutics.

  19. Hierarchic Analysis Method to Evaluate Rock Burst Risk

    Directory of Open Access Journals (Sweden)

    Ming Ji

    2015-01-01

    Full Text Available In order to reasonably evaluate the risk of rock bursts in mines, the factors impacting rock bursts and the existing grading criterion on the risk of rock bursts were studied. By building a model of hierarchic analysis method, the natural factors, technology factors, and management factors that influence rock bursts were analyzed and researched, which determined the degree of each factor’s influence (i.e., weight and comprehensive index. Then the grade of rock burst risk was assessed. The results showed that the assessment level generated by the model accurately reflected the actual risk degree of rock bursts in mines. The model improved the maneuverability and practicability of existing evaluation criteria and also enhanced the accuracy and science of rock burst risk assessment.

  20. Analysis of labour risks in the Spanish industrial aerospace sector

    Directory of Open Access Journals (Sweden)

    JUAN LAGUARDIA

    Full Text Available ABSTRACT Labour risk prevention is an activity integrated within Safety and Hygiene at Work in Spain. In 2003, the Electronic Declaration for Accidents at Work, Delt@ (DELTA was introduced. The industrial aerospace sector is subject to various risks. Our objective is to analyse the Spanish Industrial Aerospace Sector (SIAS using the ACSOM methodology to assess its labour risks and to prioritise preventive actions. The SIAS and the Services Subsector (SS were created and the relevant accident rate data were obtained. The ACSOM method was applied through double contrast (deviation and translocation of the SIAS or SS risk polygon with the considered pattern, accidents from all sectors (ACSOM G or the SIAS. A list of risks was obtained, ordered by action phases. In the SIAS vs. ACSOM G analysis, radiation risks were the worst, followed by overstrains. Accidents caused by living beings were also significant in the SS vs. SIAE, which will be able to be used to improve Risk Prevention. Radiation is the most significant risk in the SIAS and the SS. Preventive actions will be primary and secondary. ACSOM has shown itself to be a valid tool for the analysis of labour risks.

  1. Analysis of labour risks in the Spanish industrial aerospace sector.

    Science.gov (United States)

    Laguardia, Juan; Rubio, Emilio; Garcia, Ana; Garcia-Foncillas, Rafael

    2016-01-01

    Labour risk prevention is an activity integrated within Safety and Hygiene at Work in Spain. In 2003, the Electronic Declaration for Accidents at Work, Delt@ (DELTA) was introduced. The industrial aerospace sector is subject to various risks. Our objective is to analyse the Spanish Industrial Aerospace Sector (SIAS) using the ACSOM methodology to assess its labour risks and to prioritise preventive actions. The SIAS and the Services Subsector (SS) were created and the relevant accident rate data were obtained. The ACSOM method was applied through double contrast (deviation and translocation) of the SIAS or SS risk polygon with the considered pattern, accidents from all sectors (ACSOM G) or the SIAS. A list of risks was obtained, ordered by action phases. In the SIAS vs. ACSOM G analysis, radiation risks were the worst, followed by overstrains. Accidents caused by living beings were also significant in the SS vs. SIAE, which will be able to be used to improve Risk Prevention. Radiation is the most significant risk in the SIAS and the SS. Preventive actions will be primary and secondary. ACSOM has shown itself to be a valid tool for the analysis of labour risks.

  2. A Roadmap of Risk Diagnostic Methods: Developing an Integrated View of Risk Identification and Analysis Techniques

    National Research Council Canada - National Science Library

    Williams, Ray; Ambrose, Kate; Bentrem, Laura

    2004-01-01

    ...), which is envisioned to be a comprehensive reference tool for risk identification and analysis (RI AND A) techniques. Program Managers (PMs) responsible for developing or acquiring software-intensive systems typically identify risks in different ways...

  3. Is adaptation or transformation needed? Active nanomaterials and risk analysis

    Science.gov (United States)

    Kuzma, Jennifer; Roberts, John Patrick

    2016-07-01

    Nanotechnology has been a key area of funding and policy for the United States and globally for the past two decades. Since nanotechnology research and development became a focus and nanoproducts began to permeate the market, scholars and scientists have been concerned about how to assess the risks that they may pose to human health and the environment. The newest generation of nanomaterials includes biomolecules that can respond to and influence their environments, and there is a need to explore whether and how existing risk-analysis frameworks are challenged by such novelty. To fill this niche, we used a modified approach of upstream oversight assessment (UOA), a subset of anticipatory governance. We first selected case studies of "active nanomaterials," that are early in research and development and designed for use in multiple sectors, and then considered them under several, key risk-analysis frameworks. We found two ways in which the cases challenge the frameworks. The first category relates to how to assess risk under a narrow framing of the term (direct health and environmental harm), and the second involves the definition of what constitutes a "risk" worthy of assessment and consideration in decision making. In light of these challenges, we propose some changes for risk analysis in the face of active nanostructures in order to improve risk governance.

  4. SU-F-T-243: Major Risks in Radiotherapy. A Review Based On Risk Analysis Literature

    Energy Technology Data Exchange (ETDEWEB)

    López-Tarjuelo, J; Guasp-Tortajada, M; Iglesias-Montenegro, N; Monasor-Denia, P [Servicio de Radiofísica y Protección Radiológica, Consorcio Hospitalario Provincial de Castellón, Castellón de la Plana, España/Spain (Spain); Bouché-Babiloni, A; Morillo-Macías, V; Ferrer-Albiach, C [Servicio de Oncología Radioterápica, Consorcio Hospitalario Provincial de Castellón, Castellón de la Plana, España/Spain (Spain)

    2016-06-15

    Purpose: We present a literature review of risk analyses in radiotherapy to highlight the most reported risks and facilitate the spread of this valuable information so that professionals can be aware of these major threats before performing their own studies. Methods: We considered studies with at least an estimation of the probability of occurrence of an adverse event (O) and its associated severity (S). They cover external beam radiotherapy, brachytherapy, intraoperative radiotherapy, and stereotactic techniques. We selected only the works containing a detailed ranked series of elements or failure modes and focused on the first fully reported quartile as much. Afterward, we sorted the risk elements according to a regular radiotherapy procedure so that the resulting groups were cited in several works and be ranked in this way. Results: 29 references published between 2007 and February 2016 were studied. Publication trend has been generally rising. The most employed analysis has been the Failure mode and effect analysis (FMEA). Among references, we selected 20 works listing 258 ranked risk elements. They were sorted into 31 groups appearing at least in two different works. 11 groups appeared in at least 5 references and 5 groups did it in 7 or more papers. These last sets of risks where choosing another set of images or plan for planning or treating, errors related with contours, errors in patient positioning for treatment, human mistakes when programming treatments, and planning errors. Conclusion: There is a sufficient amount and variety of references for identifying which failure modes or elements should be addressed in a radiotherapy department before attempting a specific analysis. FMEA prevailed, but other studies such as “risk matrix” or “occurrence × severity” analyses can also lead professionals’ efforts. Risk associated with human actions ranks very high; therefore, they should be automated or at least peer-reviewed.

  5. SU-F-T-243: Major Risks in Radiotherapy. A Review Based On Risk Analysis Literature

    International Nuclear Information System (INIS)

    López-Tarjuelo, J; Guasp-Tortajada, M; Iglesias-Montenegro, N; Monasor-Denia, P; Bouché-Babiloni, A; Morillo-Macías, V; Ferrer-Albiach, C

    2016-01-01

    Purpose: We present a literature review of risk analyses in radiotherapy to highlight the most reported risks and facilitate the spread of this valuable information so that professionals can be aware of these major threats before performing their own studies. Methods: We considered studies with at least an estimation of the probability of occurrence of an adverse event (O) and its associated severity (S). They cover external beam radiotherapy, brachytherapy, intraoperative radiotherapy, and stereotactic techniques. We selected only the works containing a detailed ranked series of elements or failure modes and focused on the first fully reported quartile as much. Afterward, we sorted the risk elements according to a regular radiotherapy procedure so that the resulting groups were cited in several works and be ranked in this way. Results: 29 references published between 2007 and February 2016 were studied. Publication trend has been generally rising. The most employed analysis has been the Failure mode and effect analysis (FMEA). Among references, we selected 20 works listing 258 ranked risk elements. They were sorted into 31 groups appearing at least in two different works. 11 groups appeared in at least 5 references and 5 groups did it in 7 or more papers. These last sets of risks where choosing another set of images or plan for planning or treating, errors related with contours, errors in patient positioning for treatment, human mistakes when programming treatments, and planning errors. Conclusion: There is a sufficient amount and variety of references for identifying which failure modes or elements should be addressed in a radiotherapy department before attempting a specific analysis. FMEA prevailed, but other studies such as “risk matrix” or “occurrence × severity” analyses can also lead professionals’ efforts. Risk associated with human actions ranks very high; therefore, they should be automated or at least peer-reviewed.

  6. Zero risk fuel fabrication: a systems analysis

    International Nuclear Information System (INIS)

    1979-01-01

    Zero risk is a concept used to ensure that system requirements are developed through a systems approach such that the choice(s) among alternatives represents the balanced viewpoints of performance, achievability and risk. Requirements to ensure characteristics such as stringent accountability, low personnel exposure and etc. are needed to guide the development of component and subsystems for future LMFBR fuel supply systems. To establish a consistent and objective set of requirements, RF and M-TMC has initiated a systems requirements analysis activity. This activity pivots on judgement and experience provided by a Task Force representing industrial companies engaged in fuel fabrication in licensed facilities. The Task Force members are listed in Appendix A. Input developed by this group is presented as a starting point for the systems requirements analysis

  7. NASA's Agency-Wide Strategy for Environmental Regulatory Risk Analysis and Communication

    Science.gov (United States)

    Scroggins, Sharon; Duda, Kristen

    2008-01-01

    This viewgraph presentation gives an overview of NASA's risk analysis communication programs associated with changing environmental policies. The topics include: 1) NASA Program Transition; 2) Principal Center for Regulatory Risk Analysis and Communication (RRAC PC); and 3) Regulatory Tracking and Communication Process.

  8. Dynamic Positioning System (DPS) Risk Analysis Using Probabilistic Risk Assessment (PRA)

    Science.gov (United States)

    Thigpen, Eric B.; Boyer, Roger L.; Stewart, Michael A.; Fougere, Pete

    2017-01-01

    The National Aeronautics and Space Administration (NASA) Safety & Mission Assurance (S&MA) directorate at the Johnson Space Center (JSC) has applied its knowledge and experience with Probabilistic Risk Assessment (PRA) to projects in industries ranging from spacecraft to nuclear power plants. PRA is a comprehensive and structured process for analyzing risk in complex engineered systems and/or processes. The PRA process enables the user to identify potential risk contributors such as, hardware and software failure, human error, and external events. Recent developments in the oil and gas industry have presented opportunities for NASA to lend their PRA expertise to both ongoing and developmental projects within the industry. This paper provides an overview of the PRA process and demonstrates how this process was applied in estimating the probability that a Mobile Offshore Drilling Unit (MODU) operating in the Gulf of Mexico and equipped with a generically configured Dynamic Positioning System (DPS) loses location and needs to initiate an emergency disconnect. The PRA described in this paper is intended to be generic such that the vessel meets the general requirements of an International Maritime Organization (IMO) Maritime Safety Committee (MSC)/Circ. 645 Class 3 dynamically positioned vessel. The results of this analysis are not intended to be applied to any specific drilling vessel, although provisions were made to allow the analysis to be configured to a specific vessel if required.

  9. Work program analysis - defining the capability/risk plan

    International Nuclear Information System (INIS)

    Hrinivich, W.A.

    2004-01-01

    Bruce Power has developed and implemented an analysis methodology (Work Program Analysis) to assess and address corporate business risk associated with work group capability. Work Program Analysis is proving to be an excellent tool for identifying and supporting key business decisions facing the line and senior management at Bruce Power. The following describes the methodology, its application and the results achieved. (author)

  10. Challenges in the vulnerability and risk analysis of critical infrastructures

    International Nuclear Information System (INIS)

    Zio, Enrico

    2016-01-01

    The objective of this paper is to provide a systematic view on the problem of vulnerability and risk analysis of critical infrastructures. Reflections are made on the inherent complexities of these systems, related challenges are identified and possible ways forward for their analysis and management are indicated. Specifically: the framework of vulnerability and risk analysis is examined in relation to its application for the protection and resilience of critical infrastructures; it is argued that the complexity of these systems is a challenging characteristic, which calls for the integration of different modeling perspectives and new approaches of analysis; examples of are given in relation to the Internet and, particularly, the electric power grid, as representative of critical infrastructures and the associated complexity; the integration of different types of analyses and methods of system modeling is put forward for capturing the inherent structural and dynamic complexities of critical infrastructures and eventually evaluating their vulnerability and risk characteristics, so that decisions on protections and resilience actions can be taken with the required confidence. - Highlights: • The problem of the protection and resilience of CIs is the focus of the work. • The vulnerability and risk analysis framework for this is critically examined. • The complexity of CIs is presented as a challenge for system modeling and analysis. • The integration of different modeling perspectives of analysis is put forward as a solution. • The extension of the analysis framework to new methods for dealing with surprises and black swans is advocated.

  11. Analysis of coastal protection under rising flood risk

    Directory of Open Access Journals (Sweden)

    Megan J. Lickley

    2014-01-01

    Full Text Available Infrastructure located along the U.S. Atlantic and Gulf coasts is exposed to rising risk of flooding from sea level rise, increasing storm surge, and subsidence. In these circumstances coastal management commonly based on 100-year flood maps assuming current climatology is no longer adequate. A dynamic programming cost–benefit analysis is applied to the adaptation decision, illustrated by application to an energy facility in Galveston Bay. Projections of several global climate models provide inputs to estimates of the change in hurricane and storm surge activity as well as the increase in sea level. The projected rise in physical flood risk is combined with estimates of flood damage and protection costs in an analysis of the multi-period nature of adaptation choice. The result is a planning method, using dynamic programming, which is appropriate for investment and abandonment decisions under rising coastal risk.

  12. Risk analysis; Analisis de riesgos

    Energy Technology Data Exchange (ETDEWEB)

    Baron, J H; Nunez McLeod, J; Rivera, S S [Universidad Nacional de Cuyo, Mendoza (Argentina). Instituto de Capacitacion Especial y Desarrollo de Ingenieria Asistida por Computadora (CEDIAC)

    1997-07-01

    This book contains a selection of research works performed in the CEDIAC Institute (Cuyo National University) in the area of Risk Analysis, with specific orientations to the subjects of uncertainty and sensitivity studies, software reliability, severe accident modeling, etc. This volume presents important material for all those researches who want to have an insight in the risk analysis field, as a tool to solution several problems frequently found in the engineering and applied sciences field, as well as for the academic teachers who want to keep up to date, including the new developments and improvements continuously arising in this field. [Spanish] Este libro contiene una seleccion de trabajos de investigacion realizados dentro del Instituto de Capacitacion Especial y Desarrollo de la Ingenieria Asistida por Computadora en el area del analisis de riesgos, con una orientacion hacia el estudio de incertidumbres y sensibilidad, confiabilidad de software, modelacion de accidentes severos, etc. Este volumen recoge un material de indudable importancia e interes para todos aquellos investigadores y profesionales que desean incursionar en este campo del analisis de riesgos como herramienta para la solucion de problemas frecuentemente encontrados en la ingenieria y las ciencias aplicadas, asi como para los academicos que desean mantenerse al dia, conociendo los nuevos desarrollos y tecnicas que constantemente aparecen en su area.

  13. LANDSAFE: LANDING SITE RISK ANALYSIS SOFTWARE FRAMEWORK

    OpenAIRE

    Schmidt, Ralph; Bostelmann, Jonas; Cornet, Yves; Heipke, Christian; Philippe, Christian; Poncelet, Nadia; de Rosa, Diego; Vandeloise, Yannick

    2012-01-01

    The European Space Agency (ESA) is planning a Lunar Lander mission in the 2018 timeframe that will demonstrate precise soft landing at the polar regions of the Moon. To ensure a safe and successful landing a careful risk analysis has to be carried out. This is comprised of identifying favorable target areas and evaluating the surface conditions in these areas. Features like craters, boulders, steep slopes, rough surfaces and shadow areas have to be identified in order to assess the risk assoc...

  14. Neuronal injury external to the retina rapidly activates retinal glia, followed by elevation of markers for cell cycle re-entry and death in retinal ganglion cells.

    Directory of Open Access Journals (Sweden)

    Alba Galan

    Full Text Available Retinal ganglion cells (RGCs are neurons that relay visual signals from the retina to the brain. The RGC cell bodies reside in the retina and their fibers form the optic nerve. Full transection (axotomy of the optic nerve is an extra-retinal injury model of RGC degeneration. Optic nerve transection permits time-kinetic studies of neurodegenerative mechanisms in neurons and resident glia of the retina, the early events of which are reported here. One day after injury, and before atrophy of RGC cell bodies was apparent, glia had increased levels of phospho-Akt, phospho-S6, and phospho-ERK1/2; however, these signals were not detected in injured RGCs. Three days after injury there were increased levels of phospho-Rb and cyclin A proteins detected in RGCs, whereas these signals were not detected in glia. DNA hyperploidy was also detected in RGCs, indicative of cell cycle re-entry by these post-mitotic neurons. These events culminated in RGC death, which is delayed by pharmacological inhibition of the MAPK/ERK pathway. Our data show that a remote injury to RGC axons rapidly conveys a signal that activates retinal glia, followed by RGC cell cycle re-entry, DNA hyperploidy, and neuronal death that is delayed by preventing glial MAPK/ERK activation. These results demonstrate that complex and variable neuro-glia interactions regulate healthy and injured states in the adult mammalian retina.

  15. Risk analysis by FMEA as an element of analytical validation.

    Science.gov (United States)

    van Leeuwen, J F; Nauta, M J; de Kaste, D; Odekerken-Rombouts, Y M C F; Oldenhof, M T; Vredenbregt, M J; Barends, D M

    2009-12-05

    We subjected a Near-Infrared (NIR) analytical procedure used for screening drugs on authenticity to a Failure Mode and Effects Analysis (FMEA), including technical risks as well as risks related to human failure. An FMEA team broke down the NIR analytical method into process steps and identified possible failure modes for each step. Each failure mode was ranked on estimated frequency of occurrence (O), probability that the failure would remain undetected later in the process (D) and severity (S), each on a scale of 1-10. Human errors turned out to be the most common cause of failure modes. Failure risks were calculated by Risk Priority Numbers (RPNs)=O x D x S. Failure modes with the highest RPN scores were subjected to corrective actions and the FMEA was repeated, showing reductions in RPN scores and resulting in improvement indices up to 5.0. We recommend risk analysis as an addition to the usual analytical validation, as the FMEA enabled us to detect previously unidentified risks.

  16. A new tool for risk analysis and assessment in petrochemical plants

    Directory of Open Access Journals (Sweden)

    El-Arkam Mechhoud

    2016-09-01

    Full Text Available The aim of our work was the implementation of a new automated tool dedicated to risk analysis and assessment in petrochemical plants, based on a combination of two analysis methods: HAZOP (HAZard and OPerability and FMEA (Failure Mode and Effect Analysis. Assessment of accident scenarios is also considered. The principal advantage of the two analysis methods is to speed-up hazard identification and risk assessment and forecast the nature and impact of such accidents. Plant parameters are analyzed under a graphical interface to facilitate the exploitation of our developed approach. This automated analysis brings out the different deviations of the operating parameters of any system in the plant. Possible causes of these deviations, their consequences and preventive actions are identified. The result is risk minimization and dependability enhancement of the considered system.

  17. Management of Microbiologically Influenced Corrosion in Risk-Based Inspection Analysis

    DEFF Research Database (Denmark)

    Skovhus, Torben Lund; Andersen, Erlend S.; Hillier, Elisabeth

    2018-01-01

    Operating offshore oil and gas production facilities is often associated with high risk. To manage the risk, operators commonly use aids to support decision making in the establishment of a maintenance and inspection strategy. Risk-based inspection (RBI) analysis is widely used in the offshore...... industry as a means to justify the inspection strategy adopted. The RBI analysis is a decision-making technique that enables asset managers to identify the risk related to failure of their most critical systems and components, with an effect on safety, environmental, and business-related issues. Risk...... influenced corrosion (MIC) is a degradation mechanism that has received increased attention from corrosion engineers and asset operators in the past decades. In this paper, the most recent models that have been developed to assess the impact of MIC on asset integrity will be presented and discussed. From...

  18. Lagrangian Particle Tracking in a Discontinuous Galerkin Method for Hypersonic Reentry Flows in Dusty Environments

    Science.gov (United States)

    Ching, Eric; Lv, Yu; Ihme, Matthias

    2017-11-01

    Recent interest in human-scale missions to Mars has sparked active research into high-fidelity simulations of reentry flows. A key feature of the Mars atmosphere is the high levels of suspended dust particles, which can not only enhance erosion of thermal protection systems but also transfer energy and momentum to the shock layer, increasing surface heat fluxes. Second-order finite-volume schemes are typically employed for hypersonic flow simulations, but such schemes suffer from a number of limitations. An attractive alternative is discontinuous Galerkin methods, which benefit from arbitrarily high spatial order of accuracy, geometric flexibility, and other advantages. As such, a Lagrangian particle method is developed in a discontinuous Galerkin framework to enable the computation of particle-laden hypersonic flows. Two-way coupling between the carrier and disperse phases is considered, and an efficient particle search algorithm compatible with unstructured curved meshes is proposed. In addition, variable thermodynamic properties are considered to accommodate high-temperature gases. The performance of the particle method is demonstrated in several test cases, with focus on the accurate prediction of particle trajectories and heating augmentation. Financial support from a Stanford Graduate Fellowship and the NASA Early Career Faculty program are gratefully acknowledged.

  19. Slow [Na+]i dynamics impacts arrhythmogenesis and spiral wave reentry in cardiac myocyte ionic model.

    Science.gov (United States)

    Krogh-Madsen, Trine; Christini, David J

    2017-09-01

    Accumulation of intracellular Na + is gaining recognition as an important regulator of cardiac myocyte electrophysiology. The intracellular Na + concentration can be an important determinant of the cardiac action potential duration, can modulate the tissue-level conduction of excitation waves, and can alter vulnerability to arrhythmias. Mathematical models of cardiac electrophysiology often incorporate a dynamic intracellular Na + concentration, which changes much more slowly than the remaining variables. We investigated the dependence of several arrhythmogenesis-related factors on [Na + ] i in a mathematical model of the human atrial action potential. In cell simulations, we found that [Na + ] i accumulation stabilizes the action potential duration to variations in several conductances and that the slow dynamics of [Na + ] i impacts bifurcations to pro-arrhythmic afterdepolarizations, causing intermittency between different rhythms. In long-lasting tissue simulations of spiral wave reentry, [Na + ] i becomes spatially heterogeneous with a decreased area around the spiral wave rotation center. This heterogeneous region forms a functional anchor, resulting in diminished meandering of the spiral wave. Our findings suggest that slow, physiological, rate-dependent variations in [Na + ] i may play complex roles in cellular and tissue-level cardiac dynamics.

  20. Changes in Classes of Injury-Related Risks and Consequences of Risk-Level Drinking: a Latent Transition Analysis.

    Science.gov (United States)

    Cochran, Gerald; Field, Craig; Caetano, Raul

    2015-07-01

    Risk-level drinking, drinking and driving, and alcohol-related violence are risk factors that result in injuries. The current study sought to identify which subgroups of patients experience the most behavioral change following a brief intervention. A secondary analysis of data from a brief alcohol intervention study was conducted. The sample (N = 664) includes at-risk drinkers who experienced an injury and were admitted for care to a Level 1 trauma center. Injury-related items from the Short Inventory of Problems+6 were used to perform a latent transition analysis to describe class transitions participants experienced following discharge. Four classes emerged for the year before and after the current injury. Most individuals transitioned from higher-risk classes into those with lower risk. Some participants maintained risky profiles, and others increased risks and consequences. Drinking and driving remained a persistent problem among the study participants. Although a large portion of intervention recipients improved risks and consequences of alcohol use following discharge, more intensive intervention services may be needed for a subset of patients who showed little or no improvement.

  1. Critical asset and portfolio risk analysis: an all-hazards framework.

    Science.gov (United States)

    Ayyub, Bilal M; McGill, William L; Kaminskiy, Mark

    2007-08-01

    This article develops a quantitative all-hazards framework for critical asset and portfolio risk analysis (CAPRA) that considers both natural and human-caused hazards. Following a discussion on the nature of security threats, the need for actionable risk assessments, and the distinction between asset and portfolio-level analysis, a general formula for all-hazards risk analysis is obtained that resembles the traditional model based on the notional product of consequence, vulnerability, and threat, though with clear meanings assigned to each parameter. Furthermore, a simple portfolio consequence model is presented that yields first-order estimates of interdependency effects following a successful attack on an asset. Moreover, depending on the needs of the decisions being made and available analytical resources, values for the parameters in this model can be obtained at a high level or through detailed systems analysis. Several illustrative examples of the CAPRA methodology are provided.

  2. The role of uncertainty analysis in dose reconstruction and risk assessment

    International Nuclear Information System (INIS)

    Hoffman, F.O.; Simon, S.L.; Thiessen. K.M.

    1996-01-01

    Dose reconstruction and risk assessment rely heavily on the use of mathematical models to extrapolate information beyond the realm of direct observation. Because models are merely approximations of real systems, their predictions are inherently uncertain. As a result, full disclosure of uncertainty in dose and risk estimates is essential to achieve scientific credibility and to build public trust. The need for formal analysis of uncertainty in model predictions was presented during the nineteenth annual meeting of the NCRP. At that time, quantitative uncertainty analysis was considered a relatively new and difficult subject practiced by only a few investigators. Today, uncertainty analysis has become synonymous with the assessment process itself. When an uncertainty analysis is used iteratively within the assessment process, it can guide experimental research to refine dose and risk estimates, deferring potentially high cost or high consequence decisions until uncertainty is either acceptable or irreducible. Uncertainty analysis is now mandated for all ongoing dose reconstruction projects within the United States, a fact that distinguishes dose reconstruction from other types of exposure and risk assessments. 64 refs., 6 figs., 1 tab

  3. Atmosphere Re-Entry Simulation Using Direct Simulation Monte Carlo (DSMC Method

    Directory of Open Access Journals (Sweden)

    Francesco Pellicani

    2016-05-01

    Full Text Available Hypersonic re-entry vehicles aerothermodynamic investigations provide fundamental information to other important disciplines like materials and structures, assisting the development of thermal protection systems (TPS efficient and with a low weight. In the transitional flow regime, where thermal and chemical equilibrium is almost absent, a new numerical method for such studies has been introduced, the direct simulation Monte Carlo (DSMC numerical technique. The acceptance and applicability of the DSMC method have increased significantly in the 50 years since its invention thanks to the increase in computer speed and to the parallel computing. Anyway, further verification and validation efforts are needed to lead to its greater acceptance. In this study, the Monte Carlo simulator OpenFOAM and Sparta have been studied and benchmarked against numerical and theoretical data for inert and chemically reactive flows and the same will be done against experimental data in the near future. The results show the validity of the data found with the DSMC. The best setting of the fundamental parameters used by a DSMC simulator are presented for each software and they are compared with the guidelines deriving from the theory behind the Monte Carlo method. In particular, the number of particles per cell was found to be the most relevant parameter to achieve valid and optimized results. It is shown how a simulation with a mean value of one particle per cell gives sufficiently good results with very low computational resources. This achievement aims to reconsider the correct investigation method in the transitional regime where both the direct simulation Monte Carlo (DSMC and the computational fluid-dynamics (CFD can work, but with a different computational effort.

  4. Risk analysis of underground infrastructures in urban areas

    International Nuclear Information System (INIS)

    Cagno, Enrico; De Ambroggi, Massimiliano; Grande, Ottavio; Trucco, Paolo

    2011-01-01

    The paper presents an integrated approach for vulnerability and resilience analysis for underground infrastructures, i.e. a societal risk analysis of the failures of underground services for an urban area. The approach is based on the detailed study of (1) domino-effects for the components of a single infrastructure and for a given set of infrastructures interoperated and/or belonging to the same area; (2) risk and vulnerability analysis of a given area; (3) identification of a set of intervention guidelines, in order to improve the overall system resilience. The use of an integrated (interoperability and area) approach, breaking down the analysis area extent into sub-areas and assessing the dependencies among sub-areas both in terms of interoperability and damage propagation of critical infrastructures, demonstrates a useful advantage in terms of resilience analysis, more consistent with the 'zoned' nature of failures of the underground infrastructures. An applied case, describing the interoperability and damage propagation analysis with the evaluation of time-dependency for the infrastructures and targets and of different kinds of interventions of the underground infrastructures of a town, is presented for this purpose.

  5. Perception and acceptance of technological risk sources. Volume 2. Empirical analysis of risk perception and acceptance

    Energy Technology Data Exchange (ETDEWEB)

    Renn, O

    1981-01-01

    Volume 2 presents a comparative investigation of risk perception and acceptance. It contains the evaluations of the two experiments in social psychology and the analysis of two intensive inquiries concerning risk perception with a view to 12 different risk sources. The data of the two inquiries were acquired from a total of 200 interview partners in two cities in North-Rhine Westphalia.

  6. A Thermorisk framework for the analysis of energy systems by combining risk and exergy analysis

    International Nuclear Information System (INIS)

    Cassetti, G.; Colombo, E.; Zio, E.

    2016-01-01

    Highlights: • An exergy based analysis for improving efficiency and safety of energy systems is presented. • The relation between thermodynamic parameters and the safety characteristics is identified. • Possible modifications in the process are indicated to improve the safety of the system. - Abstract: The impact of energy production, transformation and use on the environmental resources encourage to understand the mechanisms of resource degradation and to develop proper analyses to reduce the impact of the energy systems on the environment. At the technical level, most attempts for reducing the environmental impact of energy systems focus on the improvement of process efficiency. One way toward an integrated approach is that of adopting exergy analysis for assessing efficiency and test improving design and operation solutions. The paper presents an exergy based analysis for improving efficiency and safety of energy systems, named Thermorisk analysis. The purpose of the Thermorisk analysis is to supply information to control, and eventually reduce, the risk of the systems (i.e. risk of accidents) by acting on the thermodynamic parameters and safety characteristics in the same frame. The proper combination of exergy and risk analysis allows monitoring the effects of efficiency improvement on the safety of the systems analyzed. A case study is presented, showing the potential of the analysis to identify the relation between the exergy efficiency and the risk of the system analyzed, and the contribution of inefficiencies on the safety of the process. Possible modifications in the process are indicated to improve the safety of the system.

  7. Debris Flow Risk Management Framework and Risk Analysis in Taiwan, A Preliminary Study

    Science.gov (United States)

    Tsao, Ting-Chi; Hsu, Wen-Ko; Chiou, Lin-Bin; Cheng, Chin-Tung; Lo, Wen-Chun; Chen, Chen-Yu; Lai, Cheng-Nong; Ju, Jiun-Ping

    2010-05-01

    Taiwan is located on a seismically active mountain belt between the Philippine Sea plate and Eurasian plate. After 1999's Chi-Chi earthquake (Mw=7.6), landslide and debris flow occurred frequently. In Aug. 2009, Typhoon Morakot struck Taiwan and numerous landslides and debris flow events, some with tremendous fatalities, were observed. With limited resources, authorities should establish a disaster management system to cope with slope disaster risks more effectively. Since 2006, Taiwan's authority in charge of debris flow management, the Soil and Water Conservation Bureau (SWCB), completed the basic investigation and data collection of 1,503 potential debris flow creeks around Taiwan. During 2008 and 2009, a debris flow quantitative risk analysis (QRA) framework, based on landslide risk management framework of Australia, was proposed and conducted on 106 creeks of the 30 villages with debris flow hazard history. Information and value of several types of elements at risk (bridge, road, building and crop) were gathered and integrated into a GIS layer, with the vulnerability model of each elements at risk applied. Through studying the historical hazard events of the 30 villages, numerical simulations of debris flow hazards with different magnitudes (5, 10, 25, 50, 100 and 200 years return period) were conducted, the economic losses and fatalities of each scenario were calculated for each creek. When taking annual exceeding probability into account, the annual total risk of each creek was calculated, and the results displayed on a debris flow risk map. The number of fatalities and frequency were calculated, and the F-N curves of 106 creeks were provided. For F-N curves, the individual risk to life per year of 1.0E-04 and slope of 1, which matched with international standards, were considered to be an acceptable risk. Applying the results of the 106 creeks onto the F-N curve, they were divided into 3 categories: Unacceptable, ALARP (As Low As Reasonable Practicable) and

  8. HVAC fault tree analysis for WIPP integrated risk assessment

    International Nuclear Information System (INIS)

    Kirby, P.; Iacovino, J.

    1990-01-01

    In order to evaluate the public health risk from operation of the Waste Isolation Pilot Plant (WIPP) due to potential radioactive releases, a probabilistic risk assessment of waste handling operations was conducted. One major aspect of this risk assessment involved fault tree analysis of the plant heating, ventilation, and air conditioning (HVAC) systems, which comprise the final barrier between waste handling operations and the environment. 1 refs., 1 tab

  9. Nuclear risk analysis of the Ulysses mission

    International Nuclear Information System (INIS)

    Bartram, B.W.; Vaughan, F.R.; Englehart, D.R.W.

    1991-01-01

    The use of a radioisotope thermoelectric generator fueled with plutonium-238 dioxide on the Space Shuttle-launched Ulysses mission implies some level of risk due to potential accidents. This paper describes the method used to quantify risks in the Ulysses mission Final Safety Analysis Report prepared for the U.S. Department of Energy. The starting point for the analysis described herein is following input of source term probability distributions from the General Electric Company. A Monte Carlo technique is used to develop probability distributions of radiological consequences for a range of accident scenarios thoughout the mission. Factors affecting radiological consequences are identified, the probability distribution of the effect of each factor determined, and the functional relationship among all the factors established. The probability distributions of all the factor effects are then combined using a Monte Carlo technique. The results of the analysis are presented in terms of complementary cumulative distribution functions (CCDF) by mission sub-phase, phase, and the overall mission. The CCDFs show the total probability that consequences (calculated health effects) would be equal to or greater than a given value

  10. A Graphical Adversarial Risk Analysis Model for Oil and Gas Drilling Cybersecurity

    OpenAIRE

    Vieira, Aitor Couce; Houmb, Siv Hilde; Insua, David Rios

    2014-01-01

    Oil and gas drilling is based, increasingly, on operational technology, whose cybersecurity is complicated by several challenges. We propose a graphical model for cybersecurity risk assessment based on Adversarial Risk Analysis to face those challenges. We also provide an example of the model in the context of an offshore drilling rig. The proposed model provides a more formal and comprehensive analysis of risks, still using the standard business language based on decisions, risks, and value.

  11. Terminological Ontologies for Risk and Vulnerability Analysis

    DEFF Research Database (Denmark)

    Madsen, Bodil Nistrup; Erdman Thomsen, Hanne

    2014-01-01

    Risk and vulnerability analyses are an important preliminary stage in civil contingency planning. The Danish Emergency Management Agency has developed a generic model and a set of tools that may be used in the preparedness planning, i.e. for identifying and describing society’s critical functions......, for formulating threat scenarios and for assessing consequences. Terminological ontologies, which are systems of domain specific concepts comprising concept relations and characteristics, are useful, both when describing the central concepts of risk and vulnerability analysis (meta concepts), and for further...

  12. Tutorial: Parallel Computing of Simulation Models for Risk Analysis.

    Science.gov (United States)

    Reilly, Allison C; Staid, Andrea; Gao, Michael; Guikema, Seth D

    2016-10-01

    Simulation models are widely used in risk analysis to study the effects of uncertainties on outcomes of interest in complex problems. Often, these models are computationally complex and time consuming to run. This latter point may be at odds with time-sensitive evaluations or may limit the number of parameters that are considered. In this article, we give an introductory tutorial focused on parallelizing simulation code to better leverage modern computing hardware, enabling risk analysts to better utilize simulation-based methods for quantifying uncertainty in practice. This article is aimed primarily at risk analysts who use simulation methods but do not yet utilize parallelization to decrease the computational burden of these models. The discussion is focused on conceptual aspects of embarrassingly parallel computer code and software considerations. Two complementary examples are shown using the languages MATLAB and R. A brief discussion of hardware considerations is located in the Appendix. © 2016 Society for Risk Analysis.

  13. AGROFOREST SYSTEM INVESTMENT ANALYSIS UNDER RISK

    Directory of Open Access Journals (Sweden)

    Luiz Moreira Coelho Junior

    2008-12-01

    Full Text Available Agroforestry System is the ecological and economical interaction of the use of the land, with the combination ofagriculture, livestock and forest production, in temporary sequence and in a simultaneous way. The studies of investments in projectsassume the existence of risks and uncertainties. An alternative to reduce the risk in the forest investment is the association with theagricultural. This work analyzed the situations of risk of a system agroflorestal. Monte Carlo s method comes from the theory ofsimulations and stands out as a powerful and useful tool to provide a distribution of probabilities for the analysis of decision. A totalof 10,000 interactions of the Net Present Value (VPL, of Internal Rate of Return (TIR and of the Equivalent Periodic Benefit (BPEwere made in order to establish the probability distribution. The results presented 78.65% of chance of VPL being US$ 1,410.00;77.56% of chance of TIR being 36.36%, and; 75.39% of chance of BPE being US$ 309.70; the agroforestry system presented lowinvestment risk; and the livestock is the main product of the agrossilvopastoril system, followed by charcoal.

  14. Kaplan-Meier Survival Analysis Overestimates the Risk of Revision Arthroplasty: A Meta-analysis.

    Science.gov (United States)

    Lacny, Sarah; Wilson, Todd; Clement, Fiona; Roberts, Derek J; Faris, Peter D; Ghali, William A; Marshall, Deborah A

    2015-11-01

    Although Kaplan-Meier survival analysis is commonly used to estimate the cumulative incidence of revision after joint arthroplasty, it theoretically overestimates the risk of revision in the presence of competing risks (such as death). Because the magnitude of overestimation is not well documented, the potential associated impact on clinical and policy decision-making remains unknown. We performed a meta-analysis to answer the following questions: (1) To what extent does the Kaplan-Meier method overestimate the cumulative incidence of revision after joint replacement compared with alternative competing-risks methods? (2) Is the extent of overestimation influenced by followup time or rate of competing risks? We searched Ovid MEDLINE, EMBASE, BIOSIS Previews, and Web of Science (1946, 1980, 1980, and 1899, respectively, to October 26, 2013) and included article bibliographies for studies comparing estimated cumulative incidence of revision after hip or knee arthroplasty obtained using both Kaplan-Meier and competing-risks methods. We excluded conference abstracts, unpublished studies, or studies using simulated data sets. Two reviewers independently extracted data and evaluated the quality of reporting of the included studies. Among 1160 abstracts identified, six studies were included in our meta-analysis. The principal reason for the steep attrition (1160 to six) was that the initial search was for studies in any clinical area that compared the cumulative incidence estimated using the Kaplan-Meier versus competing-risks methods for any event (not just the cumulative incidence of hip or knee revision); we did this to minimize the likelihood of missing any relevant studies. We calculated risk ratios (RRs) comparing the cumulative incidence estimated using the Kaplan-Meier method with the competing-risks method for each study and used DerSimonian and Laird random effects models to pool these RRs. Heterogeneity was explored using stratified meta-analyses and

  15. The health risk of the agricultural production in potentially contaminated sites: an environmental-health risk analysis

    Directory of Open Access Journals (Sweden)

    Giovanni Russo

    2012-12-01

    Full Text Available Rural areas are often interested by pollution phenomena generated by agricultural activities with a high use of pesticides and/or by anthropic activities, such as industrial plants or illegal waste disposal sites, which may cause even long-range contamination. The risk for human health from the pollutants present in the environment can be quantitatively evaluated by the environmental health risk analysis set out in the Italian Legislative Decree no. 152/2006 (Italian Regulation, 2006. This analysis is the best technical-normative tool to estimate the health risks linked to the pollutants present in the environment but it does not consider the specificity of agricultural soils or the contamination of agricultural products. This study aims to provide this missing technical-normative data by identifying and applying a suitable methodology to evaluate the health risk caused by the ingestion of agricultural products grown in contaminated soils. The risk analysis was applied to two contaminated areas in southern Italy using an innovative methodology based on widely accepted parameters for the determination of polycyclic aromatic hydrocarbons (PAHs soil-plant bio-transfer factor in the case of horticultural crops. In addition, some concentration limits of PAHs in agricultural soils are proposed that may be of help to the competent authorities (health agencies, local authorities in delineating the areas requiring strict health surveillance of the food products cultivated.

  16. Aspects of the risk analysis in the process engineering industry

    International Nuclear Information System (INIS)

    Hennings, W.; Madjar, M.; Mock, R.; Reer, B.

    1996-01-01

    This document is the result of a multi-discipline working group of a portion of a project called Risk analysis for chemical plants. Within the framework of the project, only selected methods and tools of risk analysis, thus, aspects of method, were able to be discussed and developed further. Case examples from the chemical industry are dealt with in order to discuss the application of a computer assisted quantitative error analysis in this industrial sector. Included is also a comprehensive documentation of the data and results utilised in the examples. figs., tabs., refs

  17. Is adaptation or transformation needed? Active nanomaterials and risk analysis

    International Nuclear Information System (INIS)

    Kuzma, Jennifer; Roberts, John Patrick

    2016-01-01

    Nanotechnology has been a key area of funding and policy for the United States and globally for the past two decades. Since nanotechnology research and development became a focus and nanoproducts began to permeate the market, scholars and scientists have been concerned about how to assess the risks that they may pose to human health and the environment. The newest generation of nanomaterials includes biomolecules that can respond to and influence their environments, and there is a need to explore whether and how existing risk-analysis frameworks are challenged by such novelty. To fill this niche, we used a modified approach of upstream oversight assessment (UOA), a subset of anticipatory governance. We first selected case studies of “active nanomaterials,” that are early in research and development and designed for use in multiple sectors, and then considered them under several, key risk-analysis frameworks. We found two ways in which the cases challenge the frameworks. The first category relates to how to assess risk under a narrow framing of the term (direct health and environmental harm), and the second involves the definition of what constitutes a “risk” worthy of assessment and consideration in decision making. In light of these challenges, we propose some changes for risk analysis in the face of active nanostructures in order to improve risk governance.

  18. Is adaptation or transformation needed? Active nanomaterials and risk analysis

    Energy Technology Data Exchange (ETDEWEB)

    Kuzma, Jennifer, E-mail: jkuzma@ncsu.edu [North Carolina State University, School of Public and International Affairs and Genetic Engineering and Society Center (United States); Roberts, John Patrick [North Carolina State University, School of Public and International Affairs (United States)

    2016-07-15

    Nanotechnology has been a key area of funding and policy for the United States and globally for the past two decades. Since nanotechnology research and development became a focus and nanoproducts began to permeate the market, scholars and scientists have been concerned about how to assess the risks that they may pose to human health and the environment. The newest generation of nanomaterials includes biomolecules that can respond to and influence their environments, and there is a need to explore whether and how existing risk-analysis frameworks are challenged by such novelty. To fill this niche, we used a modified approach of upstream oversight assessment (UOA), a subset of anticipatory governance. We first selected case studies of “active nanomaterials,” that are early in research and development and designed for use in multiple sectors, and then considered them under several, key risk-analysis frameworks. We found two ways in which the cases challenge the frameworks. The first category relates to how to assess risk under a narrow framing of the term (direct health and environmental harm), and the second involves the definition of what constitutes a “risk” worthy of assessment and consideration in decision making. In light of these challenges, we propose some changes for risk analysis in the face of active nanostructures in order to improve risk governance.

  19. Country risk analysis

    International Nuclear Information System (INIS)

    David, A.

    1992-01-01

    This paper reports that the oil industry has been an internationally based industry that has been heavily dependent on outside financing sources. Historically, financing came from investment houses that, in most cases, participated in the projects as equity investors. However, investment companies can no longer satisfy the capital requirements of the current high level of exploration and development activities. The current trend is to involve commercial banks on a purely lending basis. Commercial banks, by their nature, are risk averse. In the case of oil and gas exploration and production they are asked to take not only technical risk and price risk but geopolitical risk as well. Methods have been developed by commercial banks to reduce technical and price risks to point which enables them to be comfortable with a loan. However, geopolitical risks are more difficult to assess. The risk associated with many countries are the nationalization of the investment, new tax restrictions, restriction of currency movements, and/or revisions to the production sharing agreements

  20. A Graphical Adversarial Risk Analysis Model for Oil and Gas Drilling Cybersecurity

    Directory of Open Access Journals (Sweden)

    Aitor Couce Vieira

    2014-04-01

    Full Text Available Oil and gas drilling is based, increasingly, on operational technology, whose cybersecurity is complicated by several challenges. We propose a graphical model for cybersecurity risk assessment based on Adversarial Risk Analysis to face those challenges. We also provide an example of the model in the context of an offshore drilling rig. The proposed model provides a more formal and comprehensive analysis of risks, still using the standard business language based on decisions, risks, and value.

  1. Surplus analysis of Sparre Andersen insurance risk processes

    CERN Document Server

    Willmot, Gordon E

    2017-01-01

    This carefully written monograph covers the Sparre Andersen process in an actuarial context using the renewal process as the model for claim counts. A unified reference on Sparre Andersen (renewal risk) processes is included, often missing from existing literature. The authors explore recent results and analyse various risk theoretic quantities associated with the event of ruin, including the time of ruin and the deficit of ruin. Particular attention is given to the explicit identification of defective renewal equation components, which are needed to analyse various risk theoretic quantities and are also relevant in other subject areas of applied probability such as dams and storage processes, as well as queuing theory. Aimed at researchers interested in risk/ruin theory and related areas, this work will also appeal to graduate students in classical and modern risk theory and Gerber-Shiu analysis.

  2. Case studies: Risk-based analysis of technical specifications

    International Nuclear Information System (INIS)

    Wagner, D.P.; Minton, L.A.; Gaertner, J.P.

    1987-01-01

    The SOCRATES computer program uses the results of a Probabilistic Risk Assessment (PRA) or a system level risk analysis to calculate changes in risk due to changes in the surveillance test interval and/or the allowed outage time stated in the technical specification. The computer program can accommodate various testing strategies (such as staggered or simultaneous testing) to allow modeling of component testing as it is carried out at a plant. The methods and computer program are an integral part of a larger decision process aimed at determining benefits from technical specification changes. These benefits can include cost savings to the utilities by reducing forced shutdowns with no adverse impacts on risk. Three summaries of case study applications are included to demonstrate the types of results that can be achieved through risk-based evaluation of technical specifications. (orig.)

  3. Automated procedure for performing computer security risk analysis

    International Nuclear Information System (INIS)

    Smith, S.T.; Lim, J.J.

    1984-05-01

    Computers, the invisible backbone of nuclear safeguards, monitor and control plant operations and support many materials accounting systems. Our automated procedure to assess computer security effectiveness differs from traditional risk analysis methods. The system is modeled as an interactive questionnaire, fully automated on a portable microcomputer. A set of modular event trees links the questionnaire to the risk assessment. Qualitative scores are obtained for target vulnerability, and qualitative impact measures are evaluated for a spectrum of threat-target pairs. These are then combined by a linguistic algebra to provide an accurate and meaningful risk measure. 12 references, 7 figures

  4. Conflicting Incentives Risk Analysis: A Case Study of the Normative Peer Review Process

    Directory of Open Access Journals (Sweden)

    Gaute Wangen

    2015-07-01

    Full Text Available This paper presents an approach to conduct risk assessments of complex incentive systems, using a case study of the normative Peer Review Process (PRP. This research centers on appliances and adaptations of the Conflicting Incentives Risk Analysis (CIRA. First as an approach to Root Cause Analysis of a known incident, and then for a full assessment of the incentives in the PRP together with possible risk treatments. CIRA uses an alternative notion of risk, where risk modeling is in terms of conflicting incentives between the risk owner and the stakeholders concerning the execution of actions. Compared to traditional risk assessment approaches, CIRA provides an insight into the underlying incentives behind a risk, and not just the technical vulnerability, likelihood and consequence. The main contributions of this work are an approach to obtain insight into incentives as root causes, and an approach to detecting and analyzing risks from incentives in the normative PRP. This paper also discusses risk treatments in terms of incentives to make the PRP more robust, together with a discussion of how to approach risk analysis of incentives.

  5. Risk as analysis and risk as feelings: some thoughts about affect, reason, risk, and rationality.

    Science.gov (United States)

    Slovic, Paul; Finucane, Melissa L; Peters, Ellen; MacGregor, Donald G

    2004-04-01

    Modern theories in cognitive psychology and neuroscience indicate that there are two fundamental ways in which human beings comprehend risk. The "analytic system" uses algorithms and normative rules, such as probability calculus, formal logic, and risk assessment. It is relatively slow, effortful, and requires conscious control. The "experiential system" is intuitive, fast, mostly automatic, and not very accessible to conscious awareness. The experiential system enabled human beings to survive during their long period of evolution and remains today the most natural and most common way to respond to risk. It relies on images and associations, linked by experience to emotion and affect (a feeling that something is good or bad). This system represents risk as a feeling that tells us whether it is safe to walk down this dark street or drink this strange-smelling water. Proponents of formal risk analysis tend to view affective responses to risk as irrational. Current wisdom disputes this view. The rational and the experiential systems operate in parallel and each seems to depend on the other for guidance. Studies have demonstrated that analytic reasoning cannot be effective unless it is guided by emotion and affect. Rational decision making requires proper integration of both modes of thought. Both systems have their advantages, biases, and limitations. Now that we are beginning to understand the complex interplay between emotion and reason that is essential to rational behavior, the challenge before us is to think creatively about what this means for managing risk. On the one hand, how do we apply reason to temper the strong emotions engendered by some risk events? On the other hand, how do we infuse needed "doses of feeling" into circumstances where lack of experience may otherwise leave us too "coldly rational"? This article addresses these important questions.

  6. ANALYSIS METHODS OF BANKRUPTCY RISK IN ROMANIAN ENERGY MINING INDUSTRY

    Directory of Open Access Journals (Sweden)

    CORICI MARIAN CATALIN

    2016-12-01

    Full Text Available The study is an analysis of bankruptcy risk and assessing the economic performance of the entity in charge of energy mining industry from southwest region. The scientific activity assesses the risk of bankruptcy using score’s method and some indicators witch reflecting the results obtained and elements from organization balance sheet involved in mining and energy which contributes to the stability of the national energy system. Analysis undertaken is focused on the application of the business organization models that allow a comprehensive assessment of the risk of bankruptcy and be an instrument of its forecast. In this study will be highlighted developments bankruptcy risk within the organization through the Altman model and Conan-Holder model in order to show a versatile image on the organization's ability to ensure business continuity

  7. The Financial Analysis with Focus of Risks in the Banking System

    Directory of Open Access Journals (Sweden)

    Aleisky González-Duany

    2017-06-01

    Full Text Available The article consists in exposes the importance, need and convenience to develop a financial analysis with focus of risks in the banking activity to avoid damages and to take exactly and opportunity decisions. This analysis linked with bank risks will allow to the banking system measuring the efficiency in the different services that you render, detecting the different inherent risks to the financial activity with a former focus before, for the sake of giving fulfillment to the organizational goals

  8. Risk analysis of geothermal power plants using Failure Modes and Effects Analysis (FMEA) technique

    International Nuclear Information System (INIS)

    Feili, Hamid Reza; Akar, Navid; Lotfizadeh, Hossein; Bairampour, Mohammad; Nasiri, Sina

    2013-01-01

    Highlights: • Using Failure Modes and Effects Analysis (FMEA) to find potential failures in geothermal power plants. • We considered 5 major parts of geothermal power plants for risk analysis. • Risk Priority Number (RPN) is calculated for all failure modes. • Corrective actions are recommended to eliminate or decrease the risk of failure modes. - Abstract: Renewable energy plays a key role in the transition toward a low carbon economy and the provision of a secure supply of energy. Geothermal energy is a versatile source as a form of renewable energy that meets popular demand. Since some Geothermal Power Plants (GPPs) face various failures, the requirement of a technique for team engineering to eliminate or decrease potential failures is considerable. Because no specific published record of considering an FMEA applied to GPPs with common failure modes have been found already, in this paper, the utilization of Failure Modes and Effects Analysis (FMEA) as a convenient technique for determining, classifying and analyzing common failures in typical GPPs is considered. As a result, an appropriate risk scoring of occurrence, detection and severity of failure modes and computing the Risk Priority Number (RPN) for detecting high potential failures is achieved. In order to expedite accuracy and ability to analyze the process, XFMEA software is utilized. Moreover, 5 major parts of a GPP is studied to propose a suitable approach for developing GPPs and increasing reliability by recommending corrective actions for each failure mode

  9. A Flood Risk Assessment of Quang Nam, Vietnam Using Spatial Multicriteria Decision Analysis

    Directory of Open Access Journals (Sweden)

    Chinh Luu

    2018-04-01

    Full Text Available Vietnam is highly vulnerable to flood and storm impacts. Holistic flood risk assessment maps that adequately consider flood risk factors of hazard, exposure, and vulnerability are not available. These are vital for flood risk preparedness and disaster mitigation measures at the local scale. Unfortunately, there is a lack of knowledge about spatial multicriteria decision analysis and flood risk analysis more broadly in Vietnam. In response to this need, we identify and quantify flood risk components in Quang Nam province through spatial multicriteria decision analysis. The study presents a new approach to local flood risk assessment mapping, which combines historical flood marks with exposure and vulnerability data. The flood risk map output could assist and empower decision-makers in undertaking flood risk management activities in the province. Our study demonstrates a methodology to build flood risk assessment maps using flood mark, exposure and vulnerability data, which could be applied in other provinces in Vietnam.

  10. Multi-hazard risk analysis using the FP7 RASOR Platform

    Science.gov (United States)

    Koudogbo, Fifamè N.; Duro, Javier; Rossi, Lauro; Rudari, Roberto; Eddy, Andrew

    2014-10-01

    Climate change challenges our understanding of risk by modifying hazards and their interactions. Sudden increases in population and rapid urbanization are changing exposure to risk around the globe, making impacts harder to predict. Despite the availability of operational mapping products, there is no single tool to integrate diverse data and products across hazards, update exposure data quickly and make scenario-based predictions to support both short and long-term risk-related decisions. RASOR (Rapid Analysis and Spatialization Of Risk) will develop a platform to perform multi-hazard risk analysis for the full cycle of disaster management, including targeted support to critical infrastructure monitoring and climate change impact assessment. A scenario-driven query system simulates future scenarios based on existing or assumed conditions and compares them with historical scenarios. RASOR will thus offer a single work environment that generates new risk information across hazards, across data types (satellite EO, in-situ), across user communities (global, local, climate, civil protection, insurance, etc.) and across the world. Five case study areas are considered within the project, located in Haiti, Indonesia, Netherlands, Italy and Greece. Initially available over those demonstration areas, RASOR will ultimately offer global services to support in-depth risk assessment and full-cycle risk management.

  11. Risk analysis of analytical validations by probabilistic modification of FMEA.

    Science.gov (United States)

    Barends, D M; Oldenhof, M T; Vredenbregt, M J; Nauta, M J

    2012-05-01

    Risk analysis is a valuable addition to validation of an analytical chemistry process, enabling not only detecting technical risks, but also risks related to human failures. Failure Mode and Effect Analysis (FMEA) can be applied, using a categorical risk scoring of the occurrence, detection and severity of failure modes, and calculating the Risk Priority Number (RPN) to select failure modes for correction. We propose a probabilistic modification of FMEA, replacing the categorical scoring of occurrence and detection by their estimated relative frequency and maintaining the categorical scoring of severity. In an example, the results of traditional FMEA of a Near Infrared (NIR) analytical procedure used for the screening of suspected counterfeited tablets are re-interpretated by this probabilistic modification of FMEA. Using this probabilistic modification of FMEA, the frequency of occurrence of undetected failure mode(s) can be estimated quantitatively, for each individual failure mode, for a set of failure modes, and the full analytical procedure. Copyright © 2012 Elsevier B.V. All rights reserved.

  12. Rocky Flats Plant Live-Fire Range Risk Analysis Report

    Energy Technology Data Exchange (ETDEWEB)

    Nicolosi, S.L.; Rodriguez, M.A.

    1994-04-01

    The objective of the Live-Fire Range Risk Analysis Report (RAR) is to provide an authorization basis for operation as required by DOE 5480.16. The existing Live-Fire Range does not have a safety analysis-related authorization basis. EG&G Rocky Flats, Inc. has worked with DOE and its representatives to develop a format and content description for development of an RAR for the Live-Fire Range. Development of the RAR is closely aligned with development of the design for a baffle system to control risks from errant projectiles. DOE 5480.16 requires either an RAR or a safety analysis report (SAR) for live-fire ranges. An RAR rather than a SAR was selected in order to gain flexibility to more closely address the safety analysis and conduct of operation needs for a live-fire range in a cost-effective manner.

  13. Economic impact assessment in pest risk analysis

    NARCIS (Netherlands)

    Soliman, T.A.A.; Mourits, M.C.M.; Oude Lansink, A.G.J.M.; Werf, van der W.

    2010-01-01

    According to international treaties, phytosanitary measures against introduction and spread of invasive plant pests must be justified by a science-based pest risk analysis (PRA). Part of the PRA consists of an assessment of potential economic consequences. This paper evaluates the main available

  14. Migraine Headache and Ischemic Stroke Risk: An Updated Meta-analysis

    Science.gov (United States)

    Spector, June T.; Kahn, Susan R.; Jones, Miranda R.; Jayakumar, Monisha; Dalal, Deepan; Nazarian, Saman

    2010-01-01

    Background Observational studies, including recent large cohort studies which were unavailable for prior meta-analysis, have suggested an association between migraine headache and ischemic stroke. We performed an updated meta-analysis to quantitatively summarize the strength of association between migraine and ischemic stroke risk. Methods We systematically searched electronic databases, including MEDLINE and EMBASE, through February 2009 for studies of human subjects in the English language. Study selection using a priori selection criteria, data extraction, and assessment of study quality were conducted independently by reviewer pairs using standardized forms. Results Twenty-one (60%) of 35 studies met the selection criteria, for a total of 622,381 participants (13 case-control, 8 cohort studies) included in the meta-analysis. The pooled adjusted odds ratio of ischemic stroke comparing migraineurs to non-migraineurs using a random effects model was 2.30 (95% confidence interval [CI], 1.91-2.76). The pooled adjusted effect estimates for studies that reported relative risks and hazard ratios, respectively, were 2.41 (95% CI, 1.81-3.20) and 1.52 (95% CI, 0.99-2.35). The overall pooled effect estimate was 2.04 (95% CI, 1.72-2.43). Results were robust to sensitivity analyses excluding lower quality studies. Conclusions Migraine is associated with increased ischemic stroke risk. These findings underscore the importance of identifying high-risk migraineurs with other modifiable stroke risk factors. Future studies of the effect of migraine treatment and modifiable risk factor reduction on stroke risk in migraineurs are warranted. PMID:20493462

  15. A two-state comparative implementation of peer-support intervention to link veterans to health-related services after incarceration: a study protocol.

    Science.gov (United States)

    Simmons, Molly M; Fincke, Benjamin G; Drainoni, Mari-Lynn; Kim, Bo; Byrne, Tom; Smelson, David; Casey, Kevin; Ellison, Marsha L; Visher, Christy; Blue-Howells, Jessica; McInnes, D Keith

    2017-09-12

    Approximately 600,000 persons are released from prison annually in the United States. Relatively few receive sufficient re-entry services and are at risk for unemployment, homelessness, poverty, substance abuse relapse and recidivism. Persons leaving prison who have a mental illness and/or a substance use disorder are particularly challenged. This project aims to create a peer mentor program to extend the reach and effectiveness of reentry services provided by the Department of Veterans' Affairs (VA). We will implement a peer support for reentry veterans sequentially in two states. Our outcome measures are 1) fidelity of the intervention, 2) linkage to VA health care and, 3) continued engagement in health care. The aims for this project are as follows: (1) Conduct contextual analysis to identify VA and community reentry resources, and describe how reentry veterans use them. (2) Implement peer-support, in one state, to link reentry veterans to Veterans' Health Administration (VHA) primary care, mental health, and SUD services. (3) Port the peer-support intervention to another, geographically, and contextually different state. This intervention involves a 2-state sequential implementation study (Massachusetts, followed by Pennsylvania) using a Facilitation Implementation strategy. We will conduct formative and summative analyses, including assessment of fidelity, and a matched comparison group to evaluate the intervention's outcomes of veteran linkage and engagement in VHA health care (using health care utilization measures). The study proceeds in 3 phases. We anticipate that a peer support program will be effective at improving the reentry process for veterans, particularly in linking them to health, mental health, and SUD services and helping them to stay engaged in those services. It will fill a gap by providing veterans with access to a trusted individual, who understands their experience as a veteran and who has experienced justice involvement. The outputs from

  16. Risk analysis in oil spill response planning

    International Nuclear Information System (INIS)

    Chernoplekov, A.N.; Alexandrov, A.A.

    2005-01-01

    Tiered response is a basic approach to emergency plans, including oil spill response (OSR). This paper delineates a huge set of accidental scenarios within a certain tier of response generated by a computer during risk assessment. Parameters such as the amount of oil spilled, duration of discharge and types of losses should be provided in OSR scenarios. Examples of applications include offshore installations, sub sea or onshore pipelines, and localized onshore facilities. The paper demonstrates how to use risk analysis results for delineating all likely spills into groups that need a specific tier response. The best world practices and Russian regulatory approaches were outlined and compared. Corresponding algorithms were developed and their application in pipelines was presented. The algorithm combines expert's skills and spill trajectory modeling with the net environmental benefit analysis principle into the incident specific emergency response planning. 9 refs., 13 tabs., 2 figs

  17. State of the art in benefit-risk analysis: introduction.

    Science.gov (United States)

    Verhagen, H; Tijhuis, M J; Gunnlaugsdóttir, H; Kalogeras, N; Leino, O; Luteijn, J M; Magnússon, S H; Odekerken, G; Pohjola, M V; Tuomisto, J T; Ueland, Ø; White, B C; Holm, F

    2012-01-01

    Risk-taking is normal in everyday life if there are associated (perceived) benefits. Benefit-Risk Analysis (BRA) compares the risk of a situation to its related benefits and addresses the acceptability of the risk. Over the past years BRA in relation to food and food ingredients has gained attention. Food, and even the same food ingredient, may confer both beneficial and adverse effects. Measures directed at food safety may lead to suboptimal or insufficient levels of ingredients from a benefit perspective. In BRA, benefits and risks of food (ingredients) are assessed in one go and may conditionally be expressed into one currency. This allows the comparison of adverse and beneficial effects to be qualitative and quantitative. A BRA should help policy-makers to make more informed and balanced benefit-risk management decisions. Not allowing food benefits to occur in order to guarantee food safety is a risk management decision much the same as accepting some risk in order to achieve more benefits. BRA in food and nutrition is making progress, but difficulties remain. The field may benefit from looking across its borders to learn from other research areas. The BEPRARIBEAN project (Best Practices for Risk-Benefit Analysis: experience from out of food into food; http://en.opasnet.org/w/Bepraribean) aims to do so, by working together with Medicines, Food Microbiology, Environmental Health, Economics & Marketing-Finance and Consumer Perception. All perspectives are reviewed and subsequently integrated to identify opportunities for further development of BRA for food and food ingredients. Interesting issues that emerge are the varying degrees of risk that are deemed acceptable within the areas and the trend towards more open and participatory BRA processes. A set of 6 'state of the art' papers covering the above areas and a paper integrating the separate (re)views are published in this volume. Copyright © 2011 Elsevier Ltd. All rights reserved.

  18. Risk analysis of releases from accidents during mid-loop operation at Surry

    International Nuclear Information System (INIS)

    Jo, J.; Lin, C.C.; Nimnual, S.; Mubayi, V.; Neymotin, L.

    1992-11-01

    Studies and operating experience suggest that the risk of severe accidents during low power operation and/or shutdown (LP/S) conditions could be a significant fraction of the risk at full power operation. Two studies have begun at the Nuclear Regulatory Commission (NRC) to evaluate the severe accident progression from a risk perspective during these conditions: One at the Brookhaven National Laboratory for the Surry plant, a pressurized water reactor (PWR), and the other at the Sandia National Laboratories for the Grand Gulf plant, a boiling water reactor (BWR). Each of the studies consists of three linked, but distinct, components: a Level I probabilistic risk analysis (PRA) of the initiating events, systems analysis, and accident sequences leading to core damage; a Level 2/3 analysis of accident progression, fuel damage, releases, containment performance, source term and consequences-off-site and on-site; and a detailed Human Reliability Analysis (HRA) of actions relevant to plant conditions during LP/S operations. This paper summarizes the approach taken for the Level 2/3 analysis at Surry and provides preliminary results on the risk of releases and consequences for one plant operating state, mid-loop operation, during shutdown

  19. Applying Multi-Criteria Analysis Methods for Fire Risk Assessment

    Directory of Open Access Journals (Sweden)

    Pushkina Julia

    2015-11-01

    Full Text Available The aim of this paper is to prove the application of multi-criteria analysis methods for optimisation of fire risk identification and assessment process. The object of this research is fire risk and risk assessment. The subject of the research is studying the application of analytic hierarchy process for modelling and influence assessment of various fire risk factors. Results of research conducted by the authors can be used by insurance companies to perform the detailed assessment of fire risks on the object and to calculate a risk extra charge to an insurance premium; by the state supervisory institutions to determine the compliance of a condition of object with requirements of regulations; by real state owners and investors to carry out actions for decrease in degree of fire risks and minimisation of possible losses.

  20. Transmission risk assessment of invasive fluke Fascioloides magna using GIS-modelling and multicriteria analysis methods

    Directory of Open Access Journals (Sweden)

    Juhásová L.

    2017-06-01

    Full Text Available The combination of multicriteria analysis (MCA, particularly analytic hierarchy process (AHP and geographic information system (GIS were applied for transmission risk assessment of Fascioloides magna (Trematoda; Fasciolidae in south-western Slovakia. Based on the details on F. magna life cycle, the following risk factors (RF of parasite transmission were determined: intermediate (RFIH and final hosts (RFFH (biological factors, annual precipitation (RFAP, land use (RFLU, flooded area (RFFA, and annual mean air temperature (RFAT (environmental factors. Two types of risk analyses were modelled: (1 potential risk analysis was focused on the determination of the potential risk of parasite transmission into novel territories (data on F. magna occurrence were excluded; (2 actual risk analysis considered also the summary data on F. magna occurrence in the model region (risk factor parasite occurrence RFPO included in the analysis. The results of the potential risk analysis provided novel distribution pattern and revealed new geographical area as the potential risk zone of F. magna occurrence. Although the actual risk analysis revealed all four risk zones of F. magna transmission (acceptable, moderate, undesirable and unacceptable, its outputs were significantly affected by the data on parasite occurrence what reduced the informative value of the actual transmission risk assessment.

  1. Quantitative risk analysis in two pipelines operated by TRANSPETRO

    Energy Technology Data Exchange (ETDEWEB)

    Garcia, Claudio B. [PETROBRAS Transporte S/A (TRANSPETRO), Rio de Janeiro, RJ (Brazil); Pinho, Edson [Universidade Federal Rural do Rio de Janeiro (UFRRJ), Seropedica, RJ (Brazil); Bittencourt, Euclides [Centro Universitario FIB, Salvador , BA (Brazil)

    2009-07-01

    Transportation risk analysis techniques were used to study two pipelines operated by TRANSPETRO. The Pipeline A is for the simultaneous transportation of diesel, gasoline and LPG and comprises three parts, all of them crossing rural areas. The Pipeline B is for oil transportation and one of its ends is located in an area of a high density population. Both pipelines had their risk studied using the PHAST RISK{sup R} software and the individual risk measures, the only considered measures for license purposes for this type of studies, presented level far below the maximum tolerable levels considered. (author)

  2. Living with Risk in Everyday Life - A Comparative Analysis on Handling and Reflecting Risk in Everyday Actions

    DEFF Research Database (Denmark)

    Elverdam, Beth; Hoel Felde, Lina Klara

    phones; chemicals in a nursery; elevated cholesterol was combined to analyse the concept of risk in everyday life. In-depth qualitative interviews with 46 people made it possible to analyse a general perception of risk in everyday life. Interviews were analysed using a phenomenological thematical content...... analysis. Results: Although risk is communicated in the media and by health personnel, and thus has a general presence in society, participants in everyday life place risk at the periphery of life. Risk is not part of their everyday reflections. When risk manifests itself in everyday life, it is reflected...

  3. Ischemic risk stratification by means of multivariate analysis of the heart rate variability

    International Nuclear Information System (INIS)

    Valencia, José F; Vallverdú, Montserrat; Caminal, Pere; Porta, Alberto; Voss, Andreas; Schroeder, Rico; Vázquez, Rafael; Bayés de Luna, Antonio

    2013-01-01

    In this work, a univariate and multivariate statistical analysis of indexes derived from heart rate variability (HRV) was conducted to stratify patients with ischemic dilated cardiomyopathy (IDC) in cardiac risk groups. Indexes conditional entropy, refined multiscale entropy (RMSE), detrended fluctuation analysis, time and frequency analysis, were applied to the RR interval series (beat-to-beat series), for single and multiscale complexity analysis of the HRV in IDC patients. Also, clinical parameters were considered. Two different end-points after a follow-up of three years were considered: (i) analysis A, with 151 survivor patients as a low risk group and 13 patients that suffered sudden cardiac death as a high risk group; (ii) analysis B, with 192 survivor patients as a low risk group and 30 patients that suffered cardiac mortality as a high risk group. A univariate and multivariate linear discriminant analysis was used as a statistical technique for classifying patients in risk groups. Sensitivity (Sen) and specificity (Spe) were calculated as diagnostic criteria in order to evaluate the performance of the indexes and their linear combinations. Sen and Spe values of 80.0% and 72.9%, respectively, were obtained during daytime by combining one clinical parameter and one index from RMSE, and during nighttime Sen = 80% and Spe = 73.4% were attained by combining one clinical factor and two indexes from RMSE. In particular, relatively long time scales were more relevant for classifying patients into risk groups during nighttime, while during daytime shorter scales performed better. The results suggest that the left atrial size, indexed to body surface and RMSE indexes are those that allow enhanced classification of ischemic patients in their respective risk groups, confirming that a single measurement is not enough to fully characterize ischemic risk patients and the clinical relevance of HRV complexity measures. (paper)

  4. 76 FR 76103 - Privacy Act; Notice of Proposed Rulemaking: State-78, Risk Analysis and Management Records

    Science.gov (United States)

    2011-12-06

    ... Rulemaking: State-78, Risk Analysis and Management Records SUMMARY: Notice is hereby given that the... portions of the Risk Analysis and Management (RAM) Records, State-78, system of records contain criminal...) * * * (2) * * * Risk Analysis and Management Records, STATE-78. * * * * * (b) * * * (1) * * * Risk Analysis...

  5. Technical Overview of Ecological Risk Assessment - Analysis Phase: Exposure Characterization

    Science.gov (United States)

    Exposure Characterization is the second major component of the analysis phase of a risk assessment. For a pesticide risk assessment, the exposure characterization describes the potential or actual contact of a pesticide with a plant, animal, or media.

  6. H15-42: CFD analysis for risk analysis in urban environments - Tilburg city case study

    NARCIS (Netherlands)

    Hulsbosch-Dam, C.; Mack, A.; Ratingen, S. van; Rosmuller, N.; Trijssenaar, I.

    2013-01-01

    For risk analysis studies, relatively simple dispersion models are generally applied, such as Gaussian dispersion and dense gas dispersion models. For rail transport risk analyses in the Netherlands, fixed consequence distances are applied for various standard scenarios of hazardous materials

  7. Analysis of Blade Fragment Risk at a Wind Energy Facility

    Energy Technology Data Exchange (ETDEWEB)

    Simms, David A [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Larwood, Scott [University of the Pacific

    2018-04-06

    An analysis was performed to determine the risk posed by wind turbine fragments on roads and buildings at the National Wind Technology Center at the National Renewable Energy Laboratory. The authors used a previously developed model of fragment trajectory and took into account the wind speed/direction distribution at the site and the probability of rotor failure. The risk was assessed by determining the likelihood of impact and related consequences. For both the roads and buildings, the risk varied from low to routine, which was considered acceptable. The analysis was compared with previous recommendations on wind turbine setback distances. The results showed that a setback to property lines of 2 times the overall turbine height would be acceptable. However, the setback to dwellings should probably be increased from 3 to 3.5 times the overall turbine height for an acceptable risk.

  8. Liquidity Risk Management: An Empirical Analysis on Panel Data Analysis and ISE Banking Sector

    OpenAIRE

    Sibel ÇELİK; Yasemin Deniz AKARIM

    2012-01-01

    In this paper, we test the factors affecting liquidity risk management in banking sector in Turkey by using panel regression analysis. We use the data for 9 commercial banks traded in Istanbul Stock Exchange for the period 1998-2008. In conclusion, we find that risky liquid assets and return on equity variables are negatively related with liquidity risk. However, external financing and return on asset variables are positively related with liquidity risk. This finding is importance for banks s...

  9. Advanced risk analysis of systems endangered by ESD

    International Nuclear Information System (INIS)

    Kiss, Istvan; Szedenik, Norbert; Nemeth, Balint; Gulyas, Attila; Berta, Istvan

    2008-01-01

    Evaluation of industrial processes to determine risk of fire or explosion caused by electrostatic discharge (ESD) is even nowadays qualitative in most cases. Although qualitative analysis significantly helps to make an industrial process safer, it is based on the survey of the process and strongly subjective, depending on the estimation of an expert. Fault tree analysis is a traditional method to quantify the risk; it helps to select optimal protection. However, determination of top event, secondary events and basic events of the fault tree is difficult, especially the quantification of the probabilities of the basic events. In several cases no statistical information is available for most of the events. Using fuzzy membership functions instead of simple numbers for the quantification of probabilities makes it possible to take this uncertainty into consideration. Fuzzy logic based fault tree analysis of chemical processes were made to determine the effect of basic events on the probability of the top event (explosion or fire) and its reliability.

  10. Flood Hazard and Risk Analysis in Urban Area

    Science.gov (United States)

    Huang, Chen-Jia; Hsu, Ming-hsi; Teng, Wei-Hsien; Lin, Tsung-Hsien

    2017-04-01

    Typhoons always induce heavy rainfall during summer and autumn seasons in Taiwan. Extreme weather in recent years often causes severe flooding which result in serious losses of life and property. With the rapid industrial and commercial development, people care about not only the quality of life, but also the safety of life and property. So the impact of life and property due to disaster is the most serious problem concerned by the residents. For the mitigation of the disaster impact, the flood hazard and risk analysis play an important role for the disaster prevention and mitigation. In this study, the vulnerability of Kaohsiung city was evaluated by statistics of social development factor. The hazard factors of Kaohsiung city was calculated by simulated flood depth of six different return periods and four typhoon events which result in serious flooding in Kaohsiung city. The flood risk can be obtained by means of the flood hazard and social vulnerability. The analysis results provide authority to strengthen disaster preparedness and to set up more resources in high risk areas.

  11. Risk analysis within environmental impact assessment of proposed construction activity

    Energy Technology Data Exchange (ETDEWEB)

    Zeleňáková, Martina; Zvijáková, Lenka

    2017-01-15

    Environmental impact assessment is an important process, prior to approval of the investment plan, providing a detailed examination of the likely and foreseeable impacts of proposed construction activity on the environment. The objective of this paper is to develop a specific methodology for the analysis and evaluation of environmental impacts of selected constructions – flood protection structures using risk analysis methods. The application of methodology designed for the process of environmental impact assessment will develop assumptions for further improvements or more effective implementation and performance of this process. The main objective of the paper is to improve the implementation of the environmental impact assessment process. Through the use of risk analysis methods in environmental impact assessment process, the set objective has been achieved. - Highlights: This paper is informed by an effort to develop research with the aim of: • Improving existing qualitative and quantitative methods for assessing the impacts • A better understanding of relations between probabilities and consequences • Methodology for the EIA of flood protection constructions based on risk analysis • Creative approaches in the search for environmentally friendly proposed activities.

  12. Risk analysis within environmental impact assessment of proposed construction activity

    International Nuclear Information System (INIS)

    Zeleňáková, Martina; Zvijáková, Lenka

    2017-01-01

    Environmental impact assessment is an important process, prior to approval of the investment plan, providing a detailed examination of the likely and foreseeable impacts of proposed construction activity on the environment. The objective of this paper is to develop a specific methodology for the analysis and evaluation of environmental impacts of selected constructions – flood protection structures using risk analysis methods. The application of methodology designed for the process of environmental impact assessment will develop assumptions for further improvements or more effective implementation and performance of this process. The main objective of the paper is to improve the implementation of the environmental impact assessment process. Through the use of risk analysis methods in environmental impact assessment process, the set objective has been achieved. - Highlights: This paper is informed by an effort to develop research with the aim of: • Improving existing qualitative and quantitative methods for assessing the impacts • A better understanding of relations between probabilities and consequences • Methodology for the EIA of flood protection constructions based on risk analysis • Creative approaches in the search for environmentally friendly proposed activities.

  13. Risk and safety analysis of nuclear systems

    CERN Document Server

    Lee, John C

    2011-01-01

    The book has been developed in conjunction with NERS 462, a course offered every year to seniors and graduate students in the University of Michigan NERS program. The first half of the book covers the principles of risk analysis, the techniques used to develop and update a reliability data base, the reliability of multi-component systems, Markov methods used to analyze the unavailability of systems with repairs, fault trees and event trees used in probabilistic risk assessments (PRAs), and failure modes of systems. All of this material is general enough that it could be used in non-nuclear a

  14. Game Theoretic Risk Analysis of Security Threats

    CERN Document Server

    Bier, Vicki M

    2008-01-01

    Introduces reliability and risk analysis in the face of threats by intelligent agents. This book covers applications to networks, including problems in both telecommunications and transportation. It provides a set of tools for applying game theory TO reliability problems in the presence of intentional, intelligent threats

  15. Gambler Risk Perception: A Mental Model and Grounded Theory Analysis.

    Science.gov (United States)

    Spurrier, Michael; Blaszczynski, Alexander; Rhodes, Paul

    2015-09-01

    Few studies have investigated how gamblers perceive risk or the role of risk perception in disordered gambling. The purpose of the current study therefore was to obtain data on lay gamblers' beliefs on these variables and their effects on decision-making, behaviour, and disordered gambling aetiology. Fifteen regular lay gamblers (non-problem/low risk, moderate risk and problem gamblers) completed a semi-structured interview following mental models and grounded theory methodologies. Gambler interview data was compared to an expert 'map' of risk-perception, to identify comparative gaps or differences associated with harmful or safe gambling. Systematic overlapping processes of data gathering and analysis were used to iteratively extend, saturate, test for exception, and verify concepts and themes emerging from the data. The preliminary findings suggested that gambler accounts supported the presence of expert conceptual constructs, and to some degree the role of risk perception in protecting against or increasing vulnerability to harm and disordered gambling. Gambler accounts of causality, meaning, motivation, and strategy were highly idiosyncratic, and often contained content inconsistent with measures of disordered gambling. Disordered gambling appears heavily influenced by relative underestimation of risk and overvaluation of gambling, based on explicit and implicit analysis, and deliberate, innate, contextual, and learned processing evaluations and biases.

  16. Overview of methods for uncertainty analysis and sensitivity analysis in probabilistic risk assessment

    International Nuclear Information System (INIS)

    Iman, R.L.; Helton, J.C.

    1985-01-01

    Probabilistic Risk Assessment (PRA) is playing an increasingly important role in the nuclear reactor regulatory process. The assessment of uncertainties associated with PRA results is widely recognized as an important part of the analysis process. One of the major criticisms of the Reactor Safety Study was that its representation of uncertainty was inadequate. The desire for the capability to treat uncertainties with the MELCOR risk code being developed at Sandia National Laboratories is indicative of the current interest in this topic. However, as yet, uncertainty analysis and sensitivity analysis in the context of PRA is a relatively immature field. In this paper, available methods for uncertainty analysis and sensitivity analysis in a PRA are reviewed. This review first treats methods for use with individual components of a PRA and then considers how these methods could be combined in the performance of a complete PRA. In the context of this paper, the goal of uncertainty analysis is to measure the imprecision in PRA outcomes of interest, and the goal of sensitivity analysis is to identify the major contributors to this imprecision. There are a number of areas that must be considered in uncertainty analysis and sensitivity analysis for a PRA: (1) information, (2) systems analysis, (3) thermal-hydraulic phenomena/fission product behavior, (4) health and economic consequences, and (5) display of results. Each of these areas and the synthesis of them into a complete PRA are discussed

  17. A Model of Risk Analysis in Analytical Methodology for Biopharmaceutical Quality Control.

    Science.gov (United States)

    Andrade, Cleyton Lage; Herrera, Miguel Angel De La O; Lemes, Elezer Monte Blanco

    2018-01-01

    One key quality control parameter for biopharmaceutical products is the analysis of residual cellular DNA. To determine small amounts of DNA (around 100 pg) that may be in a biologically derived drug substance, an analytical method should be sensitive, robust, reliable, and accurate. In principle, three techniques have the ability to measure residual cellular DNA: radioactive dot-blot, a type of hybridization; threshold analysis; and quantitative polymerase chain reaction. Quality risk management is a systematic process for evaluating, controlling, and reporting of risks that may affects method capabilities and supports a scientific and practical approach to decision making. This paper evaluates, by quality risk management, an alternative approach to assessing the performance risks associated with quality control methods used with biopharmaceuticals, using the tool hazard analysis and critical control points. This tool provides the possibility to find the steps in an analytical procedure with higher impact on method performance. By applying these principles to DNA analysis methods, we conclude that the radioactive dot-blot assay has the largest number of critical control points, followed by quantitative polymerase chain reaction, and threshold analysis. From the analysis of hazards (i.e., points of method failure) and the associated method procedure critical control points, we conclude that the analytical methodology with the lowest risk for performance failure for residual cellular DNA testing is quantitative polymerase chain reaction. LAY ABSTRACT: In order to mitigate the risk of adverse events by residual cellular DNA that is not completely cleared from downstream production processes, regulatory agencies have required the industry to guarantee a very low level of DNA in biologically derived pharmaceutical products. The technique historically used was radioactive blot hybridization. However, the technique is a challenging method to implement in a quality

  18. Integrated Reliability and Risk Analysis System (IRRAS)

    International Nuclear Information System (INIS)

    Russell, K.D.; McKay, M.K.; Sattison, M.B.; Skinner, N.L.; Wood, S.T.; Rasmuson, D.M.

    1992-01-01

    The Integrated Reliability and Risk Analysis System (IRRAS) is a state-of-the-art, microcomputer-based probabilistic risk assessment (PRA) model development and analysis tool to address key nuclear plant safety issues. IRRAS is an integrated software tool that gives the user the ability to create and analyze fault trees and accident sequences using a microcomputer. This program provides functions that range from graphical fault tree construction to cut set generation and quantification. Version 1.0 of the IRRAS program was released in February of 1987. Since that time, many user comments and enhancements have been incorporated into the program providing a much more powerful and user-friendly system. This version has been designated IRRAS 4.0 and is the subject of this Reference Manual. Version 4.0 of IRRAS provides the same capabilities as Version 1.0 and adds a relational data base facility for managing the data, improved functionality, and improved algorithm performance

  19. Risk Analysis of a Fuel Storage Terminal Using HAZOP and FTA

    Directory of Open Access Journals (Sweden)

    José Luis Fuentes-Bargues

    2017-06-01

    Full Text Available The size and complexity of industrial chemical plants, together with the nature of the products handled, means that an analysis and control of the risks involved is required. This paper presents a methodology for risk analysis in chemical and allied industries that is based on a combination of HAZard and OPerability analysis (HAZOP and a quantitative analysis of the most relevant risks through the development of fault trees, fault tree analysis (FTA. Results from FTA allow prioritizing the preventive and corrective measures to minimize the probability of failure. An analysis of a case study is performed; it consists in the terminal for unloading chemical and petroleum products, and the fuel storage facilities of two companies, in the port of Valencia (Spain. HAZOP analysis shows that loading and unloading areas are the most sensitive areas of the plant and where the most significant danger is a fuel spill. FTA analysis indicates that the most likely event is a fuel spill in tank truck loading area. A sensitivity analysis from the FTA results show the importance of the human factor in all sequences of the possible accidents, so it should be mandatory to improve the training of the staff of the plants.

  20. Risk Analysis of a Fuel Storage Terminal Using HAZOP and FTA.

    Science.gov (United States)

    Fuentes-Bargues, José Luis; González-Cruz, Mª Carmen; González-Gaya, Cristina; Baixauli-Pérez, Mª Piedad

    2017-06-30

    The size and complexity of industrial chemical plants, together with the nature of the products handled, means that an analysis and control of the risks involved is required. This paper presents a methodology for risk analysis in chemical and allied industries that is based on a combination of HAZard and OPerability analysis (HAZOP) and a quantitative analysis of the most relevant risks through the development of fault trees, fault tree analysis (FTA). Results from FTA allow prioritizing the preventive and corrective measures to minimize the probability of failure. An analysis of a case study is performed; it consists in the terminal for unloading chemical and petroleum products, and the fuel storage facilities of two companies, in the port of Valencia (Spain). HAZOP analysis shows that loading and unloading areas are the most sensitive areas of the plant and where the most significant danger is a fuel spill. FTA analysis indicates that the most likely event is a fuel spill in tank truck loading area. A sensitivity analysis from the FTA results show the importance of the human factor in all sequences of the possible accidents, so it should be mandatory to improve the training of the staff of the plants.

  1. Risk analysis of external radiation therapy

    International Nuclear Information System (INIS)

    Arvidsson, Marcus

    2011-09-01

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

  2. Development of seismic risk analysis methodologies at JAERI

    International Nuclear Information System (INIS)

    Tanaka, T.; Abe, K.; Ebisawa, K.; Oikawa, T.

    1988-01-01

    The usefulness of probabilistic safety assessment (PSA) is recognized worldwidely for balanced design and regulation of nuclear power plants. In Japan, the Japan Atomic Energy Research Institute (JAERI) has been engaged in developing methodologies necessary for carrying out PSA. The research and development program was started in 1980. In those days the effort was only for internal initiator PSA. In 1985 the program was expanded so as to include external event analysis. Although this expanded program is to cover various external initiators, the current effort is dedicated for seismic risk analysis. There are three levels of seismic PSA, similarly to internal initiator PSA: Level 1: Evaluation of core damage frequency, Level 2: Evaluation of radioactive release frequency and source terms, and Level 3: Evaluation of environmental consequence. In the JAERI's program, only the methodologies for level 1 seismic PSA are under development. The methodology development for seismic risk analysis is divided into two phases. The Phase I study is to establish a whole set of simple methodologies based on currently available data. In the Phase II, Sensitivity study will be carried out to identify the parameters whose uncertainty may result in lage uncertainty in seismic risk, and For such parameters, the methodology will be upgraded. Now the Phase I study has almost been completed. In this report, outlines of the study and some of its outcomes are described

  3. Hierarchical Modelling of Flood Risk for Engineering Decision Analysis

    DEFF Research Database (Denmark)

    Custer, Rocco

    protection structures in the hierarchical flood protection system - is identified. To optimise the design of protection structures, fragility and vulnerability models must allow for consideration of decision alternatives. While such vulnerability models are available for large protection structures (e...... systems, as well as the implementation of the flood risk analysis methodology and the vulnerability modelling approach are illustrated with an example application. In summary, the present thesis provides a characterisation of hierarchical flood protection systems as well as several methodologies to model...... and robust. Traditional risk management solutions, e.g. dike construction, are not particularly flexible, as they are difficult to adapt to changing risk. Conversely, the recent concept of integrated flood risk management, entailing a combination of several structural and non-structural risk management...

  4. Environmental Risk Assessment: Spatial Analysis of Chemical Hazards and Risks in South Korea

    Science.gov (United States)

    Yu, H.; Heo, S.; Kim, M.; Lee, W. K.; Jong-Ryeul, S.

    2017-12-01

    This study identified chemical hazard and risk levels in Korea by analyzing the spatial distribution of chemical factories and accidents. The number of chemical factories and accidents in 5-km2 grids were used as the attribute value for spatial analysis. First, semi-variograms were conducted to examine spatial distribution patterns and to identify spatial autocorrelation of chemical factories and accidents. Semi-variograms explained that the spatial distribution of chemical factories and accidents were spatially autocorrelated. Second, the results of the semi-variograms were used in Ordinary Kriging to estimate chemical hazard and risk level. The level values were extracted from the Ordinary Kriging result and their spatial similarity was examined by juxtaposing the two values with respect to their location. Six peaks were identified in both the hazard and risk estimation result, and the peaks correlated with major cities in Korea. Third, the estimated hazard and risk levels were classified with geometrical interval and could be classified into four quadrants: Low Hazard and Low Risk (LHLR), Low Hazard and High Risk (LHHR), High Hazard and Low Risk (HHLR), and High Hazard and High Risk (HHHR). The 4 groups identified different chemical safety management issues in Korea; relatively safe LHLR group, many chemical reseller factories were found in HHLR group, chemical transportation accidents were in the LHHR group, and an abundance of factories and accidents were in the HHHR group. Each quadrant represented different safety management obstacles in Korea, and studying spatial differences can support the establishment of an efficient risk management plan.

  5. Multi-criteria decision analysis with probabilistic risk assessment for the management of contaminated ground water

    International Nuclear Information System (INIS)

    Khadam, Ibrahim M.; Kaluarachchi, Jagath J.

    2003-01-01

    Traditionally, environmental decision analysis in subsurface contamination scenarios is performed using cost-benefit analysis. In this paper, we discuss some of the limitations associated with cost-benefit analysis, especially its definition of risk, its definition of cost of risk, and its poor ability to communicate risk-related information. This paper presents an integrated approach for management of contaminated ground water resources using health risk assessment and economic analysis through a multi-criteria decision analysis framework. The methodology introduces several important concepts and definitions in decision analysis related to subsurface contamination. These are the trade-off between population risk and individual risk, the trade-off between the residual risk and the cost of risk reduction, and cost-effectiveness as a justification for remediation. The proposed decision analysis framework integrates probabilistic health risk assessment into a comprehensive, yet simple, cost-based multi-criteria decision analysis framework. The methodology focuses on developing decision criteria that provide insight into the common questions of the decision-maker that involve a number of remedial alternatives. The paper then explores three potential approaches for alternative ranking, a structured explicit decision analysis, a heuristic approach of importance of the order of criteria, and a fuzzy logic approach based on fuzzy dominance and similarity analysis. Using formal alternative ranking procedures, the methodology seeks to present a structured decision analysis framework that can be applied consistently across many different and complex remediation settings. A simple numerical example is presented to demonstrate the proposed methodology. The results showed the importance of using an integrated approach for decision-making considering both costs and risks. Future work should focus on the application of the methodology to a variety of complex field conditions to

  6. Environmental risk analysis for nanomaterials: Review and evaluation of frameworks

    DEFF Research Database (Denmark)

    Grieger, Khara Deanne; Linkov, Igor; Hansen, Steffen Foss

    2012-01-01

    to occupational settings with minor environmental considerations, and most have not been thoroughly tested on a wide range of NM. Care should also be taken when selecting the most appropriate risk analysis strategy for a given risk context. Given this, we recommend a multi-faceted approach to assess...... the environmental risks of NM as well as increased applications and testing of the proposed frameworks for different NM....

  7. Applied decision analysis and risk evaluation

    International Nuclear Information System (INIS)

    Ferse, W.; Kruber, S.

    1995-01-01

    During 1994 the workgroup 'Applied Decision Analysis and Risk Evaluation; continued the work on the knowledge based decision support system XUMA-GEFA for the evaluation of the hazard potential of contaminated sites. Additionally a new research direction was started which aims at the support of a later stage of the treatment of contaminated sites: The clean-up decision. For the support of decisions arising at this stage, the methods of decision analysis will be used. Computational aids for evaluation and decision support were implemented and a case study at a waste disposal site in Saxony which turns out to be a danger for the surrounding groundwater ressource was initiated. (orig.)

  8. Introduction to cost-effectiveness analysis of risk reduction measures in energy systems

    International Nuclear Information System (INIS)

    1986-07-01

    The aim of this report is to introduce readers to methods of cost-effectiveness analysis and their application in risk reduction, especially in connection with the energy-producing industries. The background to the assessment of risk and the problems in estimating it quantitatively are outlined. The methodology of cost-effectiveness analysis is then described, particular attention being given to the way in which results are derived and the overall use that can be made of them. This is followed by a discussion of quantitative applications and an outline of the methods that may be used to derive estimates both of risk and the cost of reducing it. The use of cost-effectiveness analysis is illustrated in an appendix, which gives as a worked example a case study on the reduction of public risk associated with radioactive releases during normal operation of a PWR. After drawing some general conclusions the report recommends that such analyses should normally be used as an aid to risk management whenever several alternative risk reduction measures are under consideration

  9. Risk-based configuration control system: Analysis and approaches

    International Nuclear Information System (INIS)

    Samanta, P.K.; Kim, I.S.; Lofgren, E.V.; Vesely, W.E.

    1990-01-01

    This paper presents an analysis of risks associated with component outage configurations during power operation of a nuclear power plant and discusses approaches and strategies for developing a risk-based configuration control system. A configuration, as used here, is a set of component states. The objective of risk-based configuration control is to detect and control plant configurations using a risk-perspective. The configuration contributions to core-melt frequency and core-melt probability are studied for two plants. Large core-melt frequency can be caused by configurations and there are a number of such configurations that are not currently controlled by technical specifications. However, the expected frequency of occurrence of the impacting configurations is small and the actual core-melt probability contributions are also generally small. Effective strategies and criteria for controlling configuration risks are presented. Such control strategies take into consideration the risks associated with configurations, the nature and characteristics of the configuration risks, and also the practical considerations such as adequate repair times and/or options to transfer to low risk configurations. Alternative types of criteria are discussed that are not overly restrictive to result in unnecessary plant shutdown, but rather motivates effective test and maintenance practices that control risk-significant configurations to allow continued operation with an adequate margin to meet challenges to safety

  10. Risk-based configuration control system: Analysis and approaches

    International Nuclear Information System (INIS)

    Samanta, P.K.; Vesely, W.E.; Kim, I.S.; Lofgren, E.V.

    1989-01-01

    This paper presents an analysis of risks associated with component outage configurations during power operation of a nuclear power plant and discusses approaches and strategies for developing a risk-based configuration control system. A configuration, as used here, is a set of component states. The objective of risk-based configuration control is to detect and control plant configurations using a risk-perspective. The configuration contributions to core-melt frequency and core-melt probability are studied for two plants. Large core-melt frequency can be caused by configurations and there are a number of such configurations that are not currently controlled by technical specifications. However, the expected frequency of occurrence of the impacting configurations is small and the actual core-melt probability contributions are also generally small. Effective strategies and criteria for controlling configuration risks are presented. Such control strategies take into consideration the risks associated with configurations, the nature and characteristics of the configuration risks, and also the practical considerations such as adequate repair times and/or options to transfer to low risk configurations. Alternative types of criteria are discussed that are not overly restrictive to result in unnecessary plant shutdown, but rather motivates effective tests and maintenance practices that control; risk-significant configurations to allow continued operation with an adequate margin to meet challenges to safety. 3 refs., 7 figs., 2 tabs

  11. Myeloperoxidase polymorphism, menopausal status, and breast cancer risk: an update meta-analysis.

    Directory of Open Access Journals (Sweden)

    Xue Qin

    Full Text Available Myeloperoxidase (MPO is a metabolic/oxidative lysosomal enzyme secreted by reactive neutrophils at the sites of inflamed organs and tissues during phagocytosis. MPO has been either directly or indirectly linked to neoplasia, which is a well-established risk factor for many types of cancer. A large number of studies have reported the role of MPO G-463A polymorphism regarding breast-cancer risk. However, the published findings are inconsistent. Therefore, we conducted a meta-analysis to determine more precise estimations for the relationship. Eligible studies were identified by searching several electronic databases for relevant reports published before June 2012. According to the inclusion criteria and exclusion criteria, a total of five eligible studies were included in the pooled analyses. When the five eligible studies concerning MPO G-463A polymorphism were pooled into this meta-analysis, there was no evidence found for a significant association between MPO G-463A polymorphism and breast-cancer risk in any genetic model. We also categorized by ethnicity (Caucasian or Asian for subgroup analysis; according to this subgroup analysis, we found no significant association between MPO G-463A polymorphism and breast-cancer risk in any genetic model. However, in the stratified analysis for the premenopausal group, women carrying the AA genotype were found to have a significantly reduced risk (OR = 0.56, 95% CI 0.34-0.94, p = 0.027. Under the recessive model, there was a significant association between MPO G-463A polymorphism and breast-cancer risk (OR = 0.57, 95% CI 0.34-0.93, p = 0.025. We conclude that MPO-G463A polymorphism might not be a good predictor of breast-cancer risk, though menopausal status modified women's risk of developing breast cancer.

  12. The STABALID project: Risk analysis of stationary Li-ion batteries for power system applications

    International Nuclear Information System (INIS)

    Soares, F.J.; Carvalho, L.; Costa, I.C.; Iria, J.P.; Bodet, J.-M.; Jacinto, G.; Lecocq, A.; Roessner, J.; Caillard, B.; Salvi, O.

    2015-01-01

    This work presents a risk analysis performed to stationary Li-ion batteries within the framework of the STABALID project. The risk analysis had as main objective analysing the variety of hazards and dangerous situations that might be experienced by the battery during its life cycle and providing useful information on how to prevent or manage those undesired events. The first task of the risk analysis was the identification of all the hazards (or risks) that may arise during the battery life cycle. Afterwards, the hazards identified were mapped in the different stages of the battery life cycle and two analyses were performed for each stage: an internal problem analysis and an external peril analysis. For both, the dangerous phenomena and the undesirable events resulting from each hazard was evaluated in terms of probability of occurrence and severity. Then, a risk assessment was carried out according to a predefined risk matrix and a preliminary set of risk mitigation measures were proposed to reduce their probability of occurrence and/or their severity level. The results obtained show that it is possible to reduce the probability of occurrence/severity of all the risks associated to the battery life cycle to acceptable or tolerable levels. - Highlights: • Methodology for a detailed risk analysis of stationary Li-ion batteries. • Various hazards and dangerous situations are analysed with high detail. • Useful information on how to prevent or manage the undesired events is provided. • Measures to reduce probability of occurrence/severity of the risks are presented

  13. RiskChanges Spatial Decision Support system for the analysis of changing multi-hazard risk

    Science.gov (United States)

    van Westen, Cees; Zhang, Kaixi; Bakker, Wim; Andrejchenko, Vera; Berlin, Julian; Olyazadeh, Roya; Cristal, Irina

    2015-04-01

    Within the framework of the EU FP7 Marie Curie Project CHANGES and the EU FP7 Copernicus project INCREO a spatial decision support system was developed with the aim to analyse the effect of risk reduction planning alternatives on reducing the risk now and in the future, and support decision makers in selecting the best alternatives. Central to the SDSS are the stakeholders. The envisaged users of the system are organizations involved in planning of risk reduction measures, and that have staff capable of visualizing and analyzing spatial data at a municipal scale. The SDSS should be able to function in different countries with different legal frameworks and with organizations with different mandates. These could be subdivided into Civil protection organization with the mandate to design disaster response plans, Expert organizations with the mandate to design structural risk reduction measures (e.g. dams, dikes, check-dams etc), and planning organizations with the mandate to make land development plans. The SDSS can be used in different ways: analyzing the current level of risk, analyzing the best alternatives for risk reduction, the evaluation of the consequences of possible future scenarios to the risk levels, and the evaluation how different risk reduction alternatives will lead to risk reduction under different future scenarios. The SDSS is developed based on open source software and following open standards, for code as well as for data formats and service interfaces. Code development was based upon open source software as well. The architecture of the system is modular. The various parts of the system are loosely coupled, extensible, using standards for interoperability, flexible and web-based. The Spatial Decision Support System is composed of a number of integrated components. The Risk Assessment component allows to carry out spatial risk analysis, with different degrees of complexity, ranging from simple exposure (overlay of hazard and assets maps) to

  14. Risk and sensitivity analysis in relation to external events

    International Nuclear Information System (INIS)

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

    2001-01-01

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

  15. Carotenoids and risk of fracture: a meta-analysis of observational studies.

    Science.gov (United States)

    Xu, Jiuhong; Song, Chunli; Song, Xiaochao; Zhang, Xi; Li, Xinli

    2017-01-10

    To quantify the association between dietary and circulating carotenoids and fracture risk, a meta-analysis was conducted by searching MEDLINE and EMBASE databases for eligible articles published before May 2016. Five prospective and 2 case-control studies with 140,265 participants and 4,324 cases were identified in our meta-analysis. Among which 5 studies assessed the association between dietary carotenoids levels and hip fracture risk, 2 studies focused on the association between circulating carotenoids levels and any fracture risk. A random-effects model was employed to summarize the risk estimations and their 95% confidence intervals (CIs). Hip fracture risk among participants with high dietary total carotenoids intake was 28% lower than that in participants with low dietary total carotenoids (OR: 0.72; 95% CI: 0.51, 1.01). A similar risk of hip fracture was found for β-carotene based on 5 studies, the summarized OR for high vs. low dietary β-carotene was 0.72 (95% CI: 0.54, 0.95). However, a significant between-study heterogeneity was found (total carotene: I2 = 59.4%, P = 0.06; β-carotene: I2 = 74.4%, P = 0.04). Other individual carotenoids did not show significant associations with hip fracture risk. Circulating carotene levels had no significant association with any fracture risk, the pooled OR (95% CI) was 0.83 (0.59, 1.17). Based on the evidence from observational studies, our meta-analysis supported the hypothesis that higher dietary total carotenoids or β-carotene intake might be potentially associated with a low risk of hip fracture, however, future well-designed prospective cohort studies and randomized controlled trials are warranted to specify the associations between carotenoids and fracture.

  16. Frequency-Risk and Duration-Risk Relationships between Aspirin Use and Gastric Cancer: A Systematic Review and Meta-Analysis

    Science.gov (United States)

    Gao, Yanhui; Liu, Li; Chen, Sidong

    2013-01-01

    Background Although previous meta-analyses have suggested an association between aspirin use and risk of gastric cancer, current evidence is inconsistent. Additionally, it remains unclear whether there are frequency-risk and duration-risk relationships and if a threshold of effect exists. Methods We identified studies by searching MEDLINE and PUBMED databases and reviewing relevant articles. We derived the summary risk estimates using fixed-effects or random-effects model based on homogeneity analysis. The dose-response meta-analysis was performed by linear trend regression and restricted cubic spline regression. Potential heterogeneity was tested using the Q statistic and quantified with the I 2 statistic. Subgroup analyses and Galbraith plots were used to explore the potential sources of heterogeneity. Publication bias was evaluated with funnel plots and quantified by the Begg's and Egger's test. Results Fifteen studies were included in this meta-analysis. There was an overall 29% reduced risk of gastric cancer corresponding to aspirin use (RR  = 0.71, 95% CI 0.60–0.82). We found there are nonlinear frequency-risk and linear duration-risk relations between aspirin use and gastric cancer. A monotonically decreasing relation was observed only for low-frequency (≤4.5 times/week) aspirin intake (10% decreased risk for once/week, 19% for twice/week and 29% for 4.5 times/week), and the frequency threshold of aspirin use is 4.5 times per week. Regarding those with duration of aspirin use, there was a tendency towards stronger risk reduction of gastric cancer for longer aspirin use (10% decreased risk for 4 years, 19% for 8 years and 28% for 12 years), and no duration threshold was observed. Conclusion Our findings suggest that long-term (≥4 years) and low-frequency (1–4.5 times per week) aspirin use is associated with a statistically significant, dose-dependent reduction in the risk of gastric cancer. PMID:23936269

  17. Frequency-risk and duration-risk relationships between aspirin use and gastric cancer: a systematic review and meta-analysis.

    Directory of Open Access Journals (Sweden)

    Xiaohua Ye

    Full Text Available BACKGROUND: Although previous meta-analyses have suggested an association between aspirin use and risk of gastric cancer, current evidence is inconsistent. Additionally, it remains unclear whether there are frequency-risk and duration-risk relationships and if a threshold of effect exists. METHODS: We identified studies by searching MEDLINE and PUBMED databases and reviewing relevant articles. We derived the summary risk estimates using fixed-effects or random-effects model based on homogeneity analysis. The dose-response meta-analysis was performed by linear trend regression and restricted cubic spline regression. Potential heterogeneity was tested using the Q statistic and quantified with the I (2 statistic. Subgroup analyses and Galbraith plots were used to explore the potential sources of heterogeneity. Publication bias was evaluated with funnel plots and quantified by the Begg's and Egger's test. RESULTS: Fifteen studies were included in this meta-analysis. There was an overall 29% reduced risk of gastric cancer corresponding to aspirin use (RR  = 0.71, 95% CI 0.60-0.82. We found there are nonlinear frequency-risk and linear duration-risk relations between aspirin use and gastric cancer. A monotonically decreasing relation was observed only for low-frequency (≤4.5 times/week aspirin intake (10% decreased risk for once/week, 19% for twice/week and 29% for 4.5 times/week, and the frequency threshold of aspirin use is 4.5 times per week. Regarding those with duration of aspirin use, there was a tendency towards stronger risk reduction of gastric cancer for longer aspirin use (10% decreased risk for 4 years, 19% for 8 years and 28% for 12 years, and no duration threshold was observed. CONCLUSION: Our findings suggest that long-term (≥4 years and low-frequency (1-4.5 times per week aspirin use is associated with a statistically significant, dose-dependent reduction in the risk of gastric cancer.

  18. Risk factors for chronic and recurrent otitis media-a meta-analysis.

    Science.gov (United States)

    Zhang, Yan; Xu, Min; Zhang, Jin; Zeng, Lingxia; Wang, Yanfei; Zheng, Qing Yin

    2014-01-01

    Risk factors associated with chronic otitis media (COM) and recurrent otitis media (ROM) have been investigated in previous studies. The objective of this study was to integrate the findings and determine the possible risk factors for COM/ROM based on our meta-analysis. A comprehensive search of electronic bibliographic databases (PubMed, Embase, CNKI and Wanfang database) from 1964 to Dec 2012, as well as a manual search of references of articles, was performed. A total of 2971 articles were searched, and 198 full-text articles were assessed for eligibility; 24 studies were eligible for this meta-analysis. Regarding risk factors for COM/ROM, there were two to nine different studies from which the odds ratios (ORs) could be pooled. The presence of allergy or atopy increased the risk of COM/ROM (OR, 1.36; 95% CI, 1.13-1.64; P = 0.001). An upper respiratory tract infection (URTI) significantly increased the risk of COM/ROM (OR, 6.59; 95% CI, 3.13-13.89; Pmedia (AOM)/ROM increased the risk of COM/ROM (OR, 11.13; 95% CI, 1.06-116.44; P = 0.04). Passive smoke significantly increased the risk of COM/ROM (OR, 1.39; 95% CI, 1.02-1.89 P = 0.04). Low social status appeared to be a risk factor for COM/ROM (OR, 3.82; 95% CI, 1.11-13.15; P = 0.03). Our meta-analysis identified reliable conclusions that allergy/atopy, URTI, snoring, previous history of AOM/ROM, Second-hand smoke and low social status are important risk factors for COM/ROM. Other unidentified risk factors need to be identified in further studies with critical criteria.

  19. Cardiovascular disease risk among breast cancer survivors: an evolutionary concept analysis

    Directory of Open Access Journals (Sweden)

    Vo JB

    2017-02-01

    Full Text Available Jacqueline B Vo,1 Timiya S Nolan,1 David E Vance,1 Patricia A Patrician,2 Karen Meneses1 1Office of Research and Scholarship, 2Department of Family, Community Health, and Systems, University of Alabama at Birmingham School of Nursing, Birmingham, AL, USA Background: More than 3.5 million breast cancer survivors are living in the US, and the overall five-year survival rate is approaching 90%. With increased survival and cancer treatment-related cardiotoxicities, there has been a rise in cardiovascular diseases among breast cancer survivors. Yet, cardiovascular disease risk among breast cancer survivors has not been well conceptualized. The purpose of this article was to analyze and define the concept of cardiovascular disease risk among breast cancer survivors. Methods: The databases CINAHL, EMBASE, and PubMed were used to identify articles that explored cardiovascular disease risk among breast cancer survivors. The search yielded 357 articles, which were reviewed for eligibility. Thirty articles were selected based on the inclusion/exclusion criteria. The concept of cardiovascular disease risk among breast cancer survivors was analyzed using Rodgers’ evolutionary concept analysis method. Results: The analysis suggests that cardiovascular disease risk among breast cancer survivors consists of several attributes: cancer treatment (chemotherapy, targeted therapies, radiation therapy, and endocrine therapy, modifiable risk factors (obesity, physical inactivity, poor diet, and smoking, and nonmodifiable risk factors (age, family history, and race. The antecedent identified includes breast cancer diagnosis and the consequence identified includes the development of cardiovascular disease. Conclusion: Findings suggest the need for increased education and understanding of ­cardiovascular disease risk among health care providers and patients. Survivorship care plans can incorporate cardiovascular disease risk monitoring and screening. Future research

  20. Occupational and Cost Risk : Critical Analysis of Monetization Policy Risk Approach to the Spanish Law Standards

    Directory of Open Access Journals (Sweden)

    Marco Antônio César Villatore

    2016-06-01

    Full Text Available The problem that surrounds the issue of occupational risk is a phenomenon that plagues every society, because the work is a central element and gives force to the economy. In this sense, the exposure of workers to harmful activities that may cause damage to your health and physical and mental integrity, based on the monetization policy of risk adopted by the Brazilian legal system, can import costs to the workers, employers, the state and society. Thus, the present study seeks, from the labor law analysis and the use of concepts of Economic Analysis of Law, attest that the social costs caused by worker exposure to risk is, fallaciously shown, in a short-term smaller than that of prevention, but in the long run can import the burden on all parties of the employment relationship as well as the State and society, being necessary to use economic and legal measures for changing the monetization of risk policy, as in alien systems, as the Spanish Law analyzed.

  1. General overview and perspectives of risk analysis in Cuba

    International Nuclear Information System (INIS)

    Torres, A.; Rodriguez, J.M.; Vilaragut, J.J.; Valhuerdi, C.

    1995-01-01

    This papers shows a general overview of the application of risk analysis techniques in some potentially dangerous industries in Cuba. This paper summarizes the experiences of these sectors in the risk analysis with different specification levels and different approaches. Some experiences in the application of these analyses in the nuclear and aeronautical industries are shown. Some analyses of consequences in cases of accidents in the chemical industries in order to work due and improve emergency plans for responding to accident situations are presented in a more succinct manner. Also the perspectives to develop some of these tendencies and cooperation forms between them are summarized

  2. Inflatable Re-Entry Vehicle Experiment (IRVE) Design Overview

    Science.gov (United States)

    Hughes, Stephen J.; Dillman, Robert A.; Starr, Brett R.; Stephan, Ryan A.; Lindell, Michael C.; Player, Charles J.; Cheatwood, F. McNeil

    2005-01-01

    Inflatable aeroshells offer several advantages over traditional rigid aeroshells for atmospheric entry. Inflatables offer increased payload volume fraction of the launch vehicle shroud and the possibility to deliver more payload mass to the surface for equivalent trajectory constraints. An inflatable s diameter is not constrained by the launch vehicle shroud. The resultant larger drag area can provide deceleration equivalent to a rigid system at higher atmospheric altitudes, thus offering access to higher landing sites. When stowed for launch and cruise, inflatable aeroshells allow access to the payload after the vehicle is integrated for launch and offer direct access to vehicle structure for structural attachment with the launch vehicle. They also offer an opportunity to eliminate system duplication between the cruise stage and entry vehicle. There are however several potential technical challenges for inflatable aeroshells. First and foremost is the fact that they are flexible structures. That flexibility could lead to unpredictable drag performance or an aerostructural dynamic instability. In addition, durability of large inflatable structures may limit their application. They are susceptible to puncture, a potentially catastrophic insult, from many possible sources. Finally, aerothermal heating during planetary entry poses a significant challenge to a thin membrane. NASA Langley Research Center and NASA's Wallops Flight Facility are jointly developing inflatable aeroshell technology for use on future NASA missions. The technology will be demonstrated in the Inflatable Re-entry Vehicle Experiment (IRVE). This paper will detail the development of the initial IRVE inflatable system to be launched on a Terrier/Orion sounding rocket in the fourth quarter of CY2005. The experiment will demonstrate achievable packaging efficiency of the inflatable aeroshell for launch, inflation, leak performance of the inflatable system throughout the flight regime, structural

  3. Common pitfalls in statistical analysis: Absolute risk reduction, relative risk reduction, and number needed to treat

    Science.gov (United States)

    Ranganathan, Priya; Pramesh, C. S.; Aggarwal, Rakesh

    2016-01-01

    In the previous article in this series on common pitfalls in statistical analysis, we looked at the difference between risk and odds. Risk, which refers to the probability of occurrence of an event or outcome, can be defined in absolute or relative terms. Understanding what these measures represent is essential for the accurate interpretation of study results. PMID:26952180

  4. The benefits of integrating cost-benefit analysis and risk assessment

    International Nuclear Information System (INIS)

    Fisher, K.; Clarke-Whistler, K.

    1995-01-01

    It has increasingly been recognized that knowledge of risks in the absence of benefits and costs cannot dictate appropriate public policy choices. Recent evidence of this recognition includes the proposed EPA Risk Assessment and Cost-Benefit Analysis Act of 1995, a number of legislative changes in Canada and the US, and the increasing demand for field studies combining measures of impacts, risks, costs and benefits. Failure to consider relative environmental and human health risks, benefits, and costs in making public policy decisions has resulted in allocating scarce resources away from areas offering the highest levels of risk reduction and improvements in health and safety. The authors discuss the implications of not taking costs and benefits into account in addressing environmental risks, drawing on examples from both Canada and the US. The authors also present the results of their recent field work demonstrating the advantages of considering costs and benefits in making public policy and site remediation decisions, including a study on the benefits and costs of prevention, remediation and monitoring techniques applied to groundwater contamination; the benefits and costs of banning the use of chlorine; and the benefits and costs of Canada's concept of disposing of high-level nuclear waste. The authors conclude that a properly conducted Cost-Benefit Analysis can provide critical input to a Risk Assessment and can ensure that risk management decisions are efficient, cost-effective and maximize improvement to environmental and human health

  5. An analysis of the public perception of flood risk on the Belgian coast.

    Science.gov (United States)

    Kellens, Wim; Zaalberg, Ruud; Neutens, Tijs; Vanneuville, Wouter; De Maeyer, Philippe

    2011-07-01

    In recent years, perception of flood risks has become an important topic to policy makers concerned with risk management and safety issues. Knowledge of the public risk perception is considered a crucial aspect in modern flood risk management as it steers the development of effective and efficient flood mitigation strategies. This study aimed at gaining insight into the perception of flood risks along the Belgian coast. Given the importance of the tourism industry on the Belgian coast, the survey considered both inhabitants and residential tourists. Based on actual expert's risk assessments, a high and a low risk area were selected for the study. Risk perception was assessed on the basis of scaled items regarding storm surges and coastal flood risks. In addition, various personal and residence characteristics were measured. Using multiple regression analysis, risk perception was found to be primarily influenced by actual flood risk estimates, age, gender, and experience with previous flood hazards. © 2011 Society for Risk Analysis.

  6. A Method of Fire Scenarios Identification in a Consolidated Fire Risk Analysis

    International Nuclear Information System (INIS)

    Lim, Ho Gon; Han, Sang Hoon; Yang, Joon Eon

    2010-01-01

    Conventional fire PSA consider only two cases of fire scenarios, that is one for fire without propagation and the other for single propagation to neighboring compartment. Recently, a consolidated fire risk analysis using single fault tree (FT) was developed. However, the fire scenario identification in the new method is similar to conventional fire analysis method. The present study develops a new method of fire scenario identification in a consolidated fire risk analysis method. An equation for fire propagation is developed to identify fire scenario and a mapping method of fire scenarios into internal event risk model is discussed. Finally, an algorithm for automatic program is suggested

  7. Meta-analysis on shift work and risks of specific obesity types.

    Science.gov (United States)

    Sun, M; Feng, W; Wang, F; Li, P; Li, Z; Li, M; Tse, G; Vlaanderen, J; Vermeulen, R; Tse, L A

    2018-01-01

    This systematic review and meta-analysis evaluated the associations between shift work patterns and risks of specific types of obesity. PubMed was searched until March 2017 for observational studies that examined the relationships between shift work patterns and obesity. Odds ratio for obesity was extracted using a fixed-effects or random-effects model. Subgroup meta-analyses were carried out for study design, specific obesity types and characteristics of shift work pattern. A total of 28 studies were included in this meta-analysis. The overall odds ratio of night shift work was 1.23 (95% confidence interval = 1.17-1.29) for risk of obesity/overweight. Cross-sectional studies showed a higher risk of 1.26 than those with the cohort design (risk ratio = 1.10). Shift workers had a higher frequency of developing abdominal obesity (odds ratio = 1.35) than other obesity types. Permanent night workers demonstrated a 29% higher risk than rotating shift workers (odds ratio 1.43 vs. 1.14). This meta-analysis confirmed the risks of night shift work for the development of overweight and obesity with a potential gradient association suggested, especially for abdominal obesity. Modification of working schedules is recommended, particularly for prolonged permanent night work. More accurate and detailed measurements on shift work patterns should be conducted in future research. © 2017 World Obesity Federation.

  8. ANALYSIS MODELS OF THE BANKRUPTCY RISK IN ROMANIA’S ENERGY SECTOR

    Directory of Open Access Journals (Sweden)

    MIRON VASILE CRISTIAN IOACHIM

    2015-12-01

    Full Text Available The risk, as a concept found in the economic sphere of business represents an analysis area often approached by researchers from the finance and accounting field. Although it is often seen, along with cost-effectiveness and value, as a fundamental element of finance (Stancu, I., 2007, the risk has often facets that make it useful also in analyzing other sides of the economic sphere of business, such as financial position and economic performance of it. From these meanings, we believe that the most suitable for this purpose is the one through which it is analyzed the ability of an entity to avoid bankruptcy. The present study has as main objectives the presentation of bankruptcy risk of an entity from a theoretical point of view and the analysis (from an empirical and comparative point of view through the scoring method of the implementation of various models for analyzing the risk of bankruptcy (Altman, Conan-holder, Taffler, Robertson in Romania’s energy sector, in order to issue an opinion regarding the optimal method for analyzing the bankruptcy risk in the energy sector. The results show that there are significant differences regarding the analysis of the bankruptcy risk through the appliction of different models, proposing the Conan-Holder model as the most appropriate for this sector.

  9. 76 FR 76215 - Privacy Act; System of Records: State-78, Risk Analysis and Management Records

    Science.gov (United States)

    2011-12-06

    ... a system of records, Risk Analysis and Management Records, State-78, pursuant to the provisions of... INFORMATION: The Department of State proposes that the new system will be ``Risk Analysis and Management.... These standard routine uses apply to State-78, Risk Analysis and Management Records. POLICIES AND...

  10. The risk communication using the special website of the society of risk analysis for the Great East Japan Earthquake

    International Nuclear Information System (INIS)

    Tsubokawa, Hiroaki; Nagasaka, Toshinari; Sunaga, Yohei; Lee, Taiyoung; Taguchi, Hitoshi; Usuda, Yuichiro

    2011-01-01

    The Society for Risk Analysis Japan built the special website that reply to the people who are concerning the risk related to the Great East Japan Earthquake occurred on March 11, 2011. Although, there were many risk communication activities between the specialists of the risk research and citizens on the website, there are some significant problems for the risk communication using the website. This report summarizes the result of our activity. (author)

  11. An introductory guide to uncertainty analysis in environmental and health risk assessment

    International Nuclear Information System (INIS)

    Hoffman, F.O.; Hammonds, J.S.

    1992-10-01

    To compensate for the potential for overly conservative estimates of risk using standard US Environmental Protection Agency methods, an uncertainty analysis should be performed as an integral part of each risk assessment. Uncertainty analyses allow one to obtain quantitative results in the form of confidence intervals that will aid in decision making and will provide guidance for the acquisition of additional data. To perform an uncertainty analysis, one must frequently rely on subjective judgment in the absence of data to estimate the range and a probability distribution describing the extent of uncertainty about a true but unknown value for each parameter of interest. This information is formulated from professional judgment based on an extensive review of literature, analysis of the data, and interviews with experts. Various analytical and numerical techniques are available to allow statistical propagation of the uncertainty in the model parameters to a statement of uncertainty in the risk to a potentially exposed individual. Although analytical methods may be straightforward for relatively simple models, they rapidly become complicated for more involved risk assessments. Because of the tedious efforts required to mathematically derive analytical approaches to propagate uncertainty in complicated risk assessments, numerical methods such as Monte Carlo simulation should be employed. The primary objective of this report is to provide an introductory guide for performing uncertainty analysis in risk assessments being performed for Superfund sites

  12. Risk Analysis Method Based on FMEA for Transmission Line in Lightning Hazards

    Directory of Open Access Journals (Sweden)

    You-Yuan WANG

    2014-05-01

    Full Text Available Failure rate of transmission line and reliability of power system are significantly affected by Lightning meteorological factor. In view of the complexity and variability of Lightning meteorological factors, this paper presents lightning trip-out rate model of transmission line in considering distribution of ground flash density and lightning day hours. Meanwhile, presents a failure rate model of transmission line in different condition, and a risk analysis method for transmission line considering multiple risk factors based on risk quantification. This method takes Lightning meteorological factor as the main evaluation standard, and establishes risk degree evaluation system for transmission line including another five evaluation standard. Put forward the risk indicators by quantify the risk factors based on experience date of transmission line in service. Based on the risk indexes comprehensive evaluation is conducted, and the evaluation result closer to practice is achieved, providing basis for transmission line risk warning and maintenance strategy. Through the risk analysis for 220 kV transmission line in a certain power supply bureau, the effectiveness of the proposed method is validated.

  13. Meat intake and risk of bladder cancer: a meta-analysis.

    Science.gov (United States)

    Wang, Chaojun; Jiang, Hai

    2012-06-01

    Meat consumption is inconsistently associated with the development of bladder cancer in several epidemiological studies. We performed a meta-analysis of evidence for relationships of meat consumption with risk of bladder cancer. Literature searches were conducted to identify peer-reviewed manuscripts published up to October 2010. Twenty publications from 10 cohort studies and 11 case-control studies were included in the analyses. We quantified associations with bladder cancer using meta-analysis of relative risk (RR) associated with the highest versus the lowest category of meat intake using random effect model. Pooled results indicate that overall meat intake was not related to the risk of bladder cancer (RR = 1.04, 95% CI = 0.80-1.27), while high red and processed meat consumer had a significantly increased 17 and 10% risk, respectively, when comparing the highest with the lowest category of meat intake. In subgroup analyses, studies conduced in Unites States/Canada exhibited a positive relationship between high meat intake and bladder cancer risk, and studies using self-administered questionnaires for exposure assessment also showed a significant increased relative risk for high meat consumers. However, because of borderline significance and small number of publications in individual analyses, more studies, particularly well-designed prospective studies, are needed to confirm these findings.

  14. A Big Data Analysis Approach for Rail Failure Risk Assessment.

    Science.gov (United States)

    Jamshidi, Ali; Faghih-Roohi, Shahrzad; Hajizadeh, Siamak; Núñez, Alfredo; Babuska, Robert; Dollevoet, Rolf; Li, Zili; De Schutter, Bart

    2017-08-01

    Railway infrastructure monitoring is a vital task to ensure rail transportation safety. A rail failure could result in not only a considerable impact on train delays and maintenance costs, but also on safety of passengers. In this article, the aim is to assess the risk of a rail failure by analyzing a type of rail surface defect called squats that are detected automatically among the huge number of records from video cameras. We propose an image processing approach for automatic detection of squats, especially severe types that are prone to rail breaks. We measure the visual length of the squats and use them to model the failure risk. For the assessment of the rail failure risk, we estimate the probability of rail failure based on the growth of squats. Moreover, we perform severity and crack growth analyses to consider the impact of rail traffic loads on defects in three different growth scenarios. The failure risk estimations are provided for several samples of squats with different crack growth lengths on a busy rail track of the Dutch railway network. The results illustrate the practicality and efficiency of the proposed approach. © 2017 The Authors Risk Analysis published by Wiley Periodicals, Inc. on behalf of Society for Risk Analysis.

  15. Risk and train control : a framework for analysis

    Science.gov (United States)

    2001-01-01

    This report develops and demonstrates a framework for examining the effects of various train control strategies on some of the major risks of railroad operations. Analysis of hypothetical 1200-mile corridor identified the main factors that increase r...

  16. Use of Veterans Health Administration Mental Health and Substance Use Disorder Treatment After Exiting Prison: The Health Care for Reentry Veterans Program.

    Science.gov (United States)

    Finlay, Andrea K; Stimmel, Matthew; Blue-Howells, Jessica; Rosenthal, Joel; McGuire, Jim; Binswanger, Ingrid; Smelson, David; Harris, Alex H S; Frayne, Susan M; Bowe, Tom; Timko, Christine

    2017-03-01

    The Veterans Health Administration (VA) Health Care for Reentry Veterans (HCRV) program links veterans exiting prison with treatment. Among veterans served by HCRV, national VA clinical data were used to describe contact with VA health care, and mental health and substance use disorder diagnoses and treatment use. Of veterans seen for an HCRV outreach visit, 56 % had contact with VA health care. Prevalence of mental health disorders was 57 %; of whom 77 % entered mental health treatment within a month of diagnosis. Prevalence of substance use disorders was 49 %; of whom 37 % entered substance use disorder treatment within a month of diagnosis. For veterans exiting prison, increasing access to VA health care, especially for rural veterans, and for substance use disorder treatment, are important quality improvement targets.

  17. Risk factors for chronic and recurrent otitis media-a meta-analysis.

    Directory of Open Access Journals (Sweden)

    Yan Zhang

    Full Text Available Risk factors associated with chronic otitis media (COM and recurrent otitis media (ROM have been investigated in previous studies. The objective of this study was to integrate the findings and determine the possible risk factors for COM/ROM based on our meta-analysis. A comprehensive search of electronic bibliographic databases (PubMed, Embase, CNKI and Wanfang database from 1964 to Dec 2012, as well as a manual search of references of articles, was performed. A total of 2971 articles were searched, and 198 full-text articles were assessed for eligibility; 24 studies were eligible for this meta-analysis. Regarding risk factors for COM/ROM, there were two to nine different studies from which the odds ratios (ORs could be pooled. The presence of allergy or atopy increased the risk of COM/ROM (OR, 1.36; 95% CI, 1.13-1.64; P = 0.001. An upper respiratory tract infection (URTI significantly increased the risk of COM/ROM (OR, 6.59; 95% CI, 3.13-13.89; P<0.00001. Snoring appeared to be a significant risk factor for COM/ROM (OR, 1.96; 95% CI, 1.78-2.16; P<0.00001. A patient history of acute otitis media (AOM/ROM increased the risk of COM/ROM (OR, 11.13; 95% CI, 1.06-116.44; P = 0.04. Passive smoke significantly increased the risk of COM/ROM (OR, 1.39; 95% CI, 1.02-1.89 P = 0.04. Low social status appeared to be a risk factor for COM/ROM (OR, 3.82; 95% CI, 1.11-13.15; P = 0.03. Our meta-analysis identified reliable conclusions that allergy/atopy, URTI, snoring, previous history of AOM/ROM, Second-hand smoke and low social status are important risk factors for COM/ROM. Other unidentified risk factors need to be identified in further studies with critical criteria.

  18. System Analysis and Risk Assessment system (SARA) Version 4.0

    International Nuclear Information System (INIS)

    Sattison, M.B.; Russell, K.D.; Skinner, N.L.

    1992-01-01

    This NUREG is the tutorial for the System Analysis and Risk Assessment System (SARA) Version 4.0, a microcomputer-based system used to analyze the safety issues of a family [i.e., a power plant, a manufacturing facility, any facility on which a probabilistic risk assessment (PRA) might be performed]. A series of lessons are provided that walk the user through some basic steps common to most analyses performed with SARA. The example problems presented in the lessons build on one another, and in combination, lead the user through all aspects of SARA sensitivity analysis

  19. Uncertainties in Cancer Risk Coefficients for Environmental Exposure to Radionuclides. An Uncertainty Analysis for Risk Coefficients Reported in Federal Guidance Report No. 13

    Energy Technology Data Exchange (ETDEWEB)

    Pawel, David [U.S. Environmental Protection Agency; Leggett, Richard Wayne [ORNL; Eckerman, Keith F [ORNL; Nelson, Christopher [U.S. Environmental Protection Agency

    2007-01-01

    Federal Guidance Report No. 13 (FGR 13) provides risk coefficients for estimation of the risk of cancer due to low-level exposure to each of more than 800 radionuclides. Uncertainties in risk coefficients were quantified in FGR 13 for 33 cases (exposure to each of 11 radionuclides by each of three exposure pathways) on the basis of sensitivity analyses in which various combinations of plausible biokinetic, dosimetric, and radiation risk models were used to generate alternative risk coefficients. The present report updates the uncertainty analysis in FGR 13 for the cases of inhalation and ingestion of radionuclides and expands the analysis to all radionuclides addressed in that report. The analysis indicates that most risk coefficients for inhalation or ingestion of radionuclides are determined within a factor of 5 or less by current information. That is, application of alternate plausible biokinetic and dosimetric models and radiation risk models (based on the linear, no-threshold hypothesis with an adjustment for the dose and dose rate effectiveness factor) is unlikely to change these coefficients by more than a factor of 5. In this analysis the assessed uncertainty in the radiation risk model was found to be the main determinant of the uncertainty category for most risk coefficients, but conclusions concerning the relative contributions of risk and dose models to the total uncertainty in a risk coefficient may depend strongly on the method of assessing uncertainties in the risk model.

  20. Night Shift Work and Risk of Depression: Meta-analysis of Observational Studies.

    Science.gov (United States)

    Lee, Aeyoung; Myung, Seung Kwon; Cho, Jung Jin; Jung, Yu Jin; Yoon, Jong Lull; Kim, Mee Young

    2017-07-01

    This study aimed to assess whether night shift work is associated with the risk of depression by using a meta-analysis of observational studies. We searched PubMed and EMBASE in August, 2016 to locate eligible studies and investigated the association between night shift work and the risk of depression, reporting outcome measures with adjusted odds ratios (ORs) or relative risks (RRs) and 95% confidence intervals (CIs). In the meta-analysis of a total of 11 observational studies with 9 cross-sectional study, 1 longitudinal study, and 1 cohort study, night shift work was significantly associated with an increased risk of depression (OR/RR, 1.43; 95% CI, 1.24-1.64; I² = 78.0%). Also, subgroup meta-analyses by gender, night shift work duration, type of occupation, continent, and type of publication showed that night shift work was consistently associated with the increased risk of depression. The current meta-analysis suggests that night shift work is associated with the increased risk of depression. However, further large prospective cohort studies are needed to confirm this association. © 2017 The Korean Academy of Medical Sciences.